Abstract: A semiclosed-loop rebreathing system is provided for use in a hostile environment. The system is characterized by a packed bed regenerative heat exchanger providing two distinct temperature-humidity zones of breathing gas with one zone providing cool, relatively dry air and the second zone providing hot, moist air. Exhaled gas is passed through the packed bed regenerative heat exchanger to increase the temperature and humidity of the gas and is then passed through a sorbent cannister containing a lithium hydroxide bed to remove carbon dioxide. The carbon dioxide-free gas is then passed through the regenerative heat exchanger in the reverse direction to cool and dehumidify the gas to normal breathing conditions. Check valves between the heat exchanger and the sorbent cannister establish gas flow in a single direction through the lithium hydroxide bed and a flexible breathing bag interposed in the flow path prevents back pressure during inhalation/exhalation sequences.

Abstract: A system is provided for automatically controlling transformer coupled alternating-current electric lines. The secondary winding of each transformer is provided with a center tap. A switching circuit is connected to the center taps of a pair of secondary windings and includes a switch controller. An impedance is connected between the center taps of the opposite pair of secondary windings. The switching circuit has continuity when the AC lines are continuous and discontinuity with any disconnect of the AC lines. Normally-open switching means are provided in at least one AC line. The switch controller automatically opens the switching means when the AC lines become separated.

Abstract: A multi-point fluid sample collection and distribution system is provided wherein the sample inputs are made through one or more of a plurality of sampling valves to a progressive cavity pump which is not susceptible to damage by large unfiltered particles. The pump output is through a filter unit that can provide a filtered multi-point sample. An unfiltered multi-point sample is also provided. An effluent sample can be taken and applied to a second progressive cavity pump for pumping to a filter unit that can provide one or more filtered effluent samples. The second pump can also provide an unfiltered effluent sample. Means are provided to periodically back flush each filter unit without shutting off the whole system.

Abstract: A method of and apparatus for processing multispectral data is provided and which permits an operator to make parameter level changes during the processing of the data. The system is directed to production of a color classification map on a video display in which a given color represents a localized region in multispectral feature space. Interactive controls permit an operator to alter the size and change the location of these regions, permitting the classification of such region to be changed from a broad to a narrow classification.

Abstract: The present invention provides several new and useful improvements in steering and control of phased array antennas having a small number of elements, typically on the order of 5 to 17 elements. Among the improvements are increasing the number of beam steering positions, reducing the possibility of phase transients in signals received or transmitted with the antennas, and increasing control and testing capacity with respect to the antennas.

Abstract: A new and improved apparatus and method for phase detection in binary signal tracking loops wherein two bandpass detectors are alternately interchanged between electrical connection with two local code reference tracking signals in order to cancel any adverse effect of gain imbalance in the bandpass detectors and direct current offset or drift. The incoming signal is multiplied with the two local reference signals in a mixer circuit to form first and second product signals which are each separately provided to two bandpass detectors to form error signals. A dither generator controls a first switching circuit to alternately interconnect the two local reference signals to the mixer circuit during the step of multiplying and also controls a second switching circuit to alternately interconnect the error signals to a summing circuit to form a composite error signal representing a difference in levels of the two error signals from the detectors.

Abstract: The performance of a waste-water reclamation system is monitored by introducing a non-pathogenic marker virus, bacteriophage F.sub.2, into the waste-water prior to treatment and, thereafter, testing the reclaimed water for the presence of the marker virus. A test sample is first concentrated by absorbing any marker virus onto a cellulose acetate filter in the presence of a trivalent cation at low pH and then flushing the filter with a limited quantity of a glycine buffer solution to desorb any marker virus present on the filter. Photo-optical detection of indirect passive immune agglutination by polystyrene beads indicates the performance of the water reclamation system in removing the marker virus. A closed system provides for concentrating any marker virus, initiating and monitoring the passive immune agglutination reaction, and then flushing the system to prepare for another sample. Peristaltic pumps are provided for volumetric control and for positive fluid displacement.

Abstract: A lightweight, active thermal control mechanism for spacecraft use comprised of woven or unwoven cross-layered yarns where one set of yarns are composed of flexible electrically conductive metal fibers which are capable of being resistance-heated by the application of voltage and another set of yarns which are electrically non-conductive and flexible. The non-conductive yarns provide mechanical strength and preclude the passage of electrical current between metal yarns by virtue of the spacing between them. A lightweight, electrically non-conductive film is bonded to the cross-layered yarns to protect the metal yarns from the elements (minimize electrical shorts from moisture, e.g., rain), provide additional strength to the fabric and to prevent the conductive loss of heat in non-vacuum applications. The non-conductive film is metalized on its obverse side to provide a more uniform heat load distribution.

Abstract: Bit error rate is measured by sending a pseudo-random noise (PRN) code test signal simulating digital data through digital equipment to be tested. An incoming signal representing the response of the equipment being tested, together with any added noise, is received and tracked by being compared with a locally generated PRN code. Once the locally generated PRN code matches the incoming signal a tracking lock is obtained. The incoming signal is then integrated and compared bit-by-bit against the locally generated PRN code and differences between bits being compared are counted as bit errors.

Abstract: The condition sensor system comprises a condition detector which produces a pulse when a parameter of the monitored condition exceeds a desired threshold. A resettable condition counter counts each pulse. A resettable timer is preset to produce a particular time frame. The counter produces a condition signal when the accumulated number of pulses within the time frame is equal to or greater than a preset count. Control means responsive to the incoming pulses and to the condition signal produce control signals that control utilization devices. After a suitable delay, the last detected pulse simultaneously resets the pulse counter and the timer, and prepares them for sensing another condition occurrence within the time frame.The invention has particular utility in the process of detecting rocking motions of blind people. A controlled, audible, bio-feedback signal is provided which constitutes a warning to the blind person that he is rocking.

Abstract: A variable contour securing system has a retaining structure for a member whose surface contains a variable contour. The retaining mechanism includes a spaced array of adjustable spindles mounted on a housing. Each spindle has a base member support cup at one end thereof. A vacuum source is applied to the cups for seating the member adjacent to the cups. A locking mechanism sets the spindles in a predetermined position once the member has been secured to the spindle support cups.

Abstract: A valve assembly for controlling the flow of fluids between the inlet and outlet of a fluid valve. The valve assembly may comprise a barrier element disposed within the body of the valve and having a portion which is porous for providing fluid communication between the valve inlet and outlet. The valve assembly may also comprise a sealing element disposed in the valve body and movable, relative to the barrier element between a first position, in which fluid flow through the porous portion of the barrier element is sealingly blocked preventing fluid communication between the valve inlet and outlet, and a second position, in which the porous portion is unblocked, permitting fluid communication between the valve inlet and outlet.

Abstract: An adjustable securing base has a surface radius of curvature which can be adjusted to support an adjacent part on the base surface. The securing base comprises a flexible thin plate with an adjustment mechanism connected on opposite edges of the base for adjusting the plate curvature. An opening in the plate is coupled to a vacuum device for securing the part adjacent the plate surface.

Abstract: A wet oxidation process for oxidizing waste materials comprising dissolving a ruthenium salt in a reactant feed stream containing the waste materials, introducing the feed stream into a reactor, heating the reactor contents to an elevated temperature to effect deposition of a catalytic surface of ruthenium black on the interior walls of the reactor and maintaining the feed stream in the reactor for a period of time sufficient to effect at least partial oxidation of the waste materials.

Abstract: Disclosed is a malfunction detection system for detecting malfunctions in electrical signal processing circuits. In a particular embodiment shown, malfunctions of a hearing aid in the form of frequency distortion and/or inadequate amplification by the hearing aid amplifier, as well as weakening of the hearing aid power supply are detectable. A test signal is generated and a timed switching circuit periodically applies the test signal to the input of the hearing aid amplifier in place of the input signal from the microphone. The resulting amplifier output is compared with the input test signal used as a reference signal. The hearing aid battery voltage is also periodically compared to a reference voltage. Deviations from the references beyond preset limits cause a warning system to operate. In the method of the invention, the input to a circuit to be tested is periodically interrupted and, for a fixed test time interval, a test signal is applied to the circuit to be tested.

Abstract: The device concerns the circulation of cabin air through canisters which absorb and adsorb carbon dioxide, together with excess moisture, and return the scrubbed air to the cabin for recirculation. A coating on an inert substrate in granular form absorbs and adsorbs the impurities at standard temperatures and pressures, but desorbs such impurities at low pressures (vacuum) and standard temperatures. This fact is exploited by making the device in a stack of cells consisting of layers or cells which are isolated from one another flow-wise and are connected to separate manifolds and valving systems into two separate subsets. A first subset may be connected for the flow of breathable air therethrough until the polyethyleneimine of its cells is saturated with CO.sub.2 and H.sub.2 O. During the same period the second subset of cells is manifolded to a vacuum source.

Abstract: The present invention provides an apparatus for phase separating a gas-liquid mixture as might exist in a sub-critical cryogenic helium vessel for cooling a superconducting magnet at low gravity such as in planetary orbit, permitting conservation of the liquid and extended service life of the superconducting magnet.

Abstract: An open loop digital frequency multiplier with a multiplied output synchonized to low frequency clock pulses. The system includes a multi-stage digital counter which provides a pulse output as a function of an integer divisor. The integer divisor and the timing or counting cycle of the counter are interrelated to the frequency of a clock input. The counting cycle is controlled by a one-shot multivibrator which, in turn, is driven by a reference frequency input.

Abstract: Disclosed is a method and system for obtaining electronic chroma signals with a single scanning-type image device by optically producing a color multiplexed light signal using an arrangement of dichroic filter stripes. In the particular embodiment described a two-layer filter system is used to color-modulate external light which is then detected by an image pickup tube. The resulting time division multiplexed electronic signal from the pickup tube is converted by a decoder into a green color signal, and a single red-blue multiplexed signal, which is demultiplexed to produce red and blue color signals. The three primary color signals are capable of being encoded as standard NTSC color signals.

Abstract: Apparatus and method for determining the mass of a fluid comprising: a housing having an inlet and outlet for receiving and dumping the fluid, a rotary impeller within the housing for imparting centrifugal motion to the fluid and a pressure sensitive transducer attached to the housing to sense the rotating fluid pressure. In the method the fluid may be drawn into the housing by entrainment within a gas stream. The resulting mixture is then separated into two phases: gas and liquid. The gas is removed from the housing and the pressure of the liquid, under centrifugal motion, is sensed and correlated with the mass of the fluid.