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Decision-Tree Formulation With Order-1 Lateral Execution

Some decision trees can be transformed into objects executable by simple table lookups. A compact symbolic formulation enables mapping of an arbitrarily complex decision tree of a certain type into a highly computationally efficient multidimensional software object. The type of decision trees to which this formulation applies is that known in the art as the Boolean class of balanced decision trees. Parallel lateral slices of an object created by means of this formulation can be executed in constant time — considerably less time than would otherwise be required.

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Integrated Hardware and Software for No-Loss Computing

Computations on parallel processors can continue, even if one processor fails. When an algorithm is distributed across multiple threads executing on many distinct processors, a loss of one of those threads or processors can potentially result in the total loss of all the incremental results up to that point. When implementation is massively hardware distributed, then the probability of a hardware failure during the course of a long execution is potentially high. Traditionally, this problem has been addressed by establishing checkpoints where the current state of some or part of the execution is saved. Then in the event of a failure, this state information can be used to recompute that point in the execution and resume the computation from that point.

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Integral Radiator and Storage Tank

Weight and volume are reduced. A simplified, lightweight system for dissipating heat of a regenerative fuel- cell system would include a heat pipe with its evaporator end placed at the heat source and its condenser end integrated into the wall of the regenerative fuel cell system gas-storage tanks. The tank walls act as heat-radiating surfaces for cooling the regenerative fuel cell system. The system was conceived for use in outer space, where radiation is the only physical mechanism available for transferring heat to the environment. The system could also be adapted for use on propellant tanks or other large-surface-area structures to convert them to space heat-radiating structures.

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Compensation for Phase Anisotropy of a Metal Reflector

A multilayer dielectric coating would introduce an opposing phase anisotropy. A method of compensation for the polarization-dependent phase anisotropy of a metal reflector has been proposed. The essence of the method is to coat the reflector with multiple thin alternating layers of two dielectrics that have different indices of refraction, so as to introduce an opposing polarization- dependent phase anisotropy.

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Multispectral Imager With Improved Filter Wheel and Optics

“Dead” time is reduced substantially, relative to prior systems of the same type. Figure 1 schematically depicts an improved multispectral imaging system of the type that utilizes a filter wheel that contains multiple discrete narrow-band-pass filters and that is rotated at a constant high speed to acquire images in rapid succession in the corresponding spectral bands. The improvement, relative to prior systems of this type, consists of the measures taken to prevent the exposure of a focal-plane array (FPA) of photodetectors to light in more than one spectral band at any given time and to prevent exposure of the array to any light during readout. In prior systems, these measures have included, variously the use of mechanical shutters or the incorporation of wide opaque sectors (equivalent to mechanical shutters) into filter wheels. These measures introduce substantial “dead” times into each operating cycle — intervals during which image information cannot be collected and thus incoming light is wasted. In contrast, the present improved design does not involve shutters or wide opaque sectors, and it reduces dead times substantially.

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High-Resolution, Wide-Field-of-View Scanning Telescope

Narrow-angle scanning over a wide field would be achieved without slewing the entire telescope. A proposed telescope would afford high resolution over a narrow field of view (<0.10°) while scanning over a total field of view nominally 16° wide without need to slew the entire massive telescope structure. The telescope design enables resolution of a 1-m-wide object in a 50-km-wide area of the surface of the Earth as part of a 200-km-wide area field of view monitored from an orbit at an altitude of 700 km. The conceptual design of this telescope could also be adapted to other applications — both terrestrial and extraterrestrial — in which there are requirements for telescopes that afford both wide- and narrow-field capabilities.

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Simplified Microarray Technique for Identifying mRNA in Rare Samples

This method can be implemented by use of portable equipment. Two simplified methods of identifying messenger ribonucleic acid (mRNA), and compact, low-power apparatuses to implement the methods, are at the proof-of-concept stage of development. These methods are related to traditional methods based on hybridization of nucleic acid, but whereas the traditional methods must be practiced in laboratory settings, these methods could be practiced in field settings.

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