Abstract: A transient signal suppressor (10) for use in a controls system which is adapted to respond to a change in a physical parameter whenever it crosses a predetermined threshold value in a selected direction of increasing or decreasing values with respect to the threshold value and is sustained for a selected discrete time interval. The suppressor (10) includes a sensor transducer (12) for sensing the physical parameter and generating an electrical input signal whenever the sensed physical parameter crosses the threshold level in the selected direction. A manually operated switch (30A, 30B) is provided for adapting the suppressor to produce an output drive signal whenever the physical parameter crosses the threshold value in the selected direction of increasing or decreasing values.

Abstract: Hydrocarbon polymer coatings used in microelectronic manufacturing processes are anisotropically etched by atomic oxygen beams (translational energies of 0.2-20 eV, preferably 1-10 eV). Etching with hyperthermal (kinetic energy>1 eV) oxygen atom species obtains highly anisotropic etching with sharp boundaries between etched and mask-protected areas.

Abstract: An apparatus and method is disclosed for decelerating and absorbing impact of a re-entry vehicle suitable for payloads that are relatively light as well as payloads weighing several tons or more. The apparatus includes four inflatable legs displaced equidistantly from each other around a capsule or housing which contains a payload. The legs are inflated at a designated altitude after entering Earth's atmosphere to slow the descent of the re-entry vehicle. Connected between each of the four legs are drag inducing surfaces that deploy as the legs inflate. The drag inducing surfaces are triangularly shaped with one such surface being connected between each pair of legs for a total of six drag inducing surfaces. The legs have drag inducing outer surfaces which act to slow the descent of the re-entry vehicle.

Abstract: Apparatus for simulating an exoatmospheric structure, such as a spin stabilized satellite, in an environment subject to gravitational forces. The apparatus includes a floating structure which is pivotally and rotationally supported upon a gimballed bearing structure positioned adjacent the center of mass of the floating structure and suspended upon a support structure. The floating structure is translatable in either vertical direction relative to the supporting structure upon a vertically movable suspension system connected to the supporting structure. The supporting structure is provided with bearing assemblies which are adapted to engage a supporting surface for permitting freedom of movement of the supporting structure over the supporting structure in any direction.

Abstract: A reconfigurable fuzzy cell comprising a digital control programmable gain operation amplifier, an analog-to-digital converter, an electrically erasable PROM, and 8-bit counter and comparator, and supporting logic configured to achieve in real-time fuzzy systems high throughput, grade-of-membership or membership-value conversion of multi-input sensor data. The present invention provides a flexible multiplexing-capable configuration, implemented entirely in hardware, for effectuating S-, Z-, and PI-membership functions or combinations thereof, based upon fuzzy logic level-set theory. A membership value table storing "knowledge-data" for each of S-, Z-, and PI-functions is contained within a nonvolatile memory for storing bits of membership and parametric information in a plurality of address spaces. Based upon parametric and control signals, analog sensor data is digitized and converted into grade-of-membership data. In situ learn and reconfiguration modes of operation are also provided.

Abstract: A retainer member (2) suitable for retaining a gap filler (1) placed in gaps (20) between adjacent tile members (21, 22). One edge of the retainer member (2) may be attached to the gap filler (1) and another edge may be provided with a plurality of tab members (4, 5, 6, 7, 8, 9) which in an intermediate position do not interfere with placement or removal of the gap filler (1) between tile members (21, 22). The retainer member may be fabricated from a shape memory alloy which when heated to a specified memory temperature will thermally activate the tab members (4, 5, 6, 7, 8, 9) to predetermined memory positions engaging the tile members (21, 22) to retain the gap filler (1) in the gap (20).

Abstract: Neural network algorithms have impressively demonstrated the capability of modelling spatial information. On the other hand, the application of parallel distributed models to processing of temporal data has been severely restricted. The invention introduces a novel technique which adds the dimension of time to the well known back-propagatioORIGIN OF THE INVENTIONThe invention described herein was made by employees of the United States Government and ma be manufactured and used by or for the Government of the United States of America for governmental purposes without payment of any royalties thereon or therefor.

Abstract: Method and apparatus for accurately simulating locomotion in a weightless environment, specifically to prevent atrophy of a subject's musculoskeletal and cardiorespiratory systems during space travel, are disclosed. Forces, including the vertical, horizontal and lateral force generated by an individual during locomotion on a treadmill, utilizing a rigid belt with rigid transfer elements supported by low friction bogies are measured by strain gauges sensitive in their respective direction. The vertical forces produced by securing the subject to the treadmill via bungee cords in conjunction with the measured velocity of the treadmill, and the mode of locomotion are used to determine the subject's equivalent weight. The other horizontal and lateral forces are used to determine the external work produced by the subject when locomotion is performed on a nonlevel surface with an effective grade angle. The measured forces are related in such a way that the grade angle is easily determined.

Abstract: A trash removal system for space stations has a disposable trash bag member and an attached, compacted large, lightweight inflatable balloon element. When the trash bag member is filled, the astronaut places the bag member in space through an airlock. Once in the vacuum of space, the balloon element inflates. Due to a large cross-sectional area of the balloon element relative to its mass, the combined balloon element and the trash bag member are slowed by atmospheric drag to a much greater extent than the Space Station. The balloon element and bag member lose altitude and re-enter the atmosphere and the elements and contents are destroyed by aerodynamic heating.

Abstract: A hydraulically powered gas compressor receives low pressure gas and outputs a high pressure gas. The housing of the compressor defines a cylinder with a center chamber having a cross-sectional area less than the cross-sectional area of a left end chamber and a right end chamber, and a spool-type piston assembly is movable within the cylinder and includes a left end closure, a right end closure, and a center body that are in sealing engagement with the respective cylinder walls as the piston reciprocates. First and second annular compression chambers are provided between the piston enclosures and center housing portion of the compressor, thereby minimizing the spacing between the core gas and a cooled surface of the compressor. Restricted flow passageways are provided in the piston closure members and a path is provided in the central body of the piston assembly, such that hydraulic fluid flows through the piston assembly to cool the piston assembly during its operation.

Abstract: A supervised procedure for obtaining weight values for back-propagation neural networks is described. The method according to the invention performs a sequence of partial optimizations in order to determine values for the network connection weights. The partial optimization depends on a constrained representation of hidden weights derived from a singular value decomposition of the input space as well as an Iterative Least Squares optimization solution for the output weights.

Abstract: A microporous structure with layered interstitial surface treatments, and method and apparatus for preparation thereof. The structure is prepared by sequentially subjecting a uniformly surface-treated structure (10a) to atomic oxygen treatment to remove an outer layer (16) of surface treatment to a generally uniform depth, and then surface treating the so exposed layer with another surface treating agent. The atomic oxygen/surface treatment steps may optionally be repeated, each successive time to a lesser depth, to produce a microporous structure having multilayered surface treatments. The apparatus (200) employs at least one side arm (228) from a main atomic oxygen-containing chamber (202). The side arm (228) has characteristic relaxation times such that a uniform atomic oxygen dose rate is delivered to a specimen (239) positioned transversely in the side arm (228) spaced from the main gas chamber (202).

Abstract: An apparatus for image processing comprising a camera for receiving an original visual image and transforming the original visual image into an analog image, a first converter for transforming the analog image of the camera to a digital image, a processor having a single flow architecture for receiving the digital image and producing, with a single algorithm, an output image, a second converter for transforming the digital image of the processor to an analog image, and a viewer for receiving the analog image, transforming the analog image into a transformed visual image for observing the transformations applied to the original visual image. The processor comprises one or more subprocessors for the parallel reception of a digital image for producing an output matrix of the transformed visual image.

Abstract: An improved linkage assembly (10) provides for locking the pivotable position of one member (12) relative to another member (14). The linkage assembly permits the unlocking of these members, their subsequent repositioning, and the reliable relocking in a desired position without utilizing tooling. The first member (12) includes a pair of spaced apart support flanges (24,26) each having a through aperture (28) therein defining a flange female spline (29). The second member (14) has an end (42) positioned between the pair of support flanges (24,26) and also includes a through aperture (46 ) defining a pair of second member female splines (47). A pair of control members (84,86) are each slidably moveable along the common axis (32) and extend through the respective flanges (24,26). Each control member (84,86) has a male splined portion (66) which normally engages both the respective flange female spline and the second member female spline to lock the rotatable position of the first and second members.

Abstract: A method for pretreating a cellulosic waste product with microwaves is disclosed as well as a method and apparatus for converting cellulosic wastes into soluble saccharides. The invention greatly enhances a reaction rate for enzymatic hydrolysis. A feed mixture of cellulose, water and acetic acid are irradiated with microwaves at a superatmospheric pressure in an autoclave reaction vessel and the treated cellulose is enzymatically hydrolyzed in a bioreactor. The acid and enzymes are optionally separated for reuse. As a feed stock for the culture of microbes, the sugars can be further processed into ethanol or food protein. High yield, low hazard potential, low energy usage and ready preparation in space of acetic acid and the enzyme makes the present invention well suited for use on long duration space missions.

Abstract: A method of matching a first query pattern with a plurality of stored data is disclosed. For each stored data pattern, the number of components are counted which are identical to corresponding components in the first query pattern, thereby forming a set of match numbers equals the number of components in any stored pattern, that stored data pattern is displayed as an output pattern set indicating a match. If no match exists then a second query pattern is determined by modifying the first query pattern, component by component, in dependence upon both a first, global influence of all stored patterns on all components of the first query pattern and a second, particular influence of all stored patterns on each respective component of the first query pattern. The first two method steps are then repeated using the second query pattern in place of the first query pattern. If no match a third query pattern similarly is determined by modifying the second query pattern.

Abstract: A bus programmable slave module card 30 for use in a computer control system which comprises a master computer and one or more slave computer modules interfacing therewith by means of a bus and wherein each slave module includes its own microprocessor memory, and control program for acting as a single loop controller. The slave card includes a plurality of memory means corresponding to a like plurality of memory devices in the master computer, for each slave memory means its own communication lines connectable through the bus with memory communication lines of an associated memory device in the master computer, and a one-way electronic door which is switchable to either a closed condition or a one-way open condition. With the door closed, communication lines between master computer memory and slave memory are blocked.

Abstract: Human beings judge patterns (such as images) by complex mental processes, some of which may not be known, while computing machines extract features. By representing the human judgements with simple measurements and reducing them and the machine extracted features to a common metric space and fitting them by regression, the judgements of human experts rendered on a sample of patterns may be imposed on a pattern population to provide automatic classification.

Abstract: A method and apparatus are disclosed for maintaining continuous, long-term microbial control in the water supply for potable, hygiene, and experimental water for space activities, i.e., space shuttle, orbiter lab, Lunar base, Mars base, deep space missions, etc., as well as treatment of water supplies on earth. The water purification is accomplished by introduction of molecular iodine into the water supply to impart a desired iodine residual. The water is passed through an iodinated anion exchange resin bed. The iodine is bound as I.sup.-.sub.n at the anion exchange sites and releases I.sub.2 into the water stream flowing through the bed. Suitable anion exchange resins are Amberlite IRA 401S (Rohm & Haas); Dowex SBR (Dow Chemical); and Ionac ASB-1P (Sybron Corp.). The concentration of I.sub.2 in the flowing water gradually decreases and the ion-exchange bed has had to be replaced.

Abstract: A thruster nozzle sealing system and apparatus is provided for protection of spacecraft thruster motors. The system includes a sealing plug, a sealing plug insertion tool, an outer cover, an outer cover attachment, a ferry flight attachment, and a test stand. The sealing plug provents moisture from entering the thruster engine so as to prevent valve failure. The attachments are interchangeably connectable with the sealing plug. The ferry flight attachment is used during air transportation of the spacecraft, and the outer cover attachment is used during storage and service of the spacecraft. The outer cover provides protection to the thruster nozzle from mechanical damage. The test stand provides a means for testing and certifying the operating condition of each component of the system.