Redundant memory organization Patent
Redundant memory for enhanced reliability of digital data processing system
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Redundant memory for enhanced reliability of digital data processing system
Associative or content addressable memory systems - overview, bibliography, and KWIC index
Markov chain model for characterizing error sequences in digital channels with memory
Feasibility of MnBi thin films for spaceborne optical mass memory applications
Computer memory reduction through Fortran higher level language, discussing tradeoff between costs saved and additional logic hardware
Monolithic optically written and electrically read semiconductor-ferroelectric memory device employing single crystal barium titanate
Composition and composition inhomogeneity effects on plated wire memory elements strain sensitivity, considering tension and torsion sensitivities
Extraretinal correction and memory for target position, suggesting corrective tendency of eye movements in dark
Eye pupil response during short term memory task, noting postsignal cycle of dilation-constriction
Material and system research defines accurate memory characteristics in regard to write, read, erase and data operations of manganese bismuth materials.
Fabrication of integrated circuit chips to compensate for faulty memory elements is discussed. Procedure for testing chips to determine extent of redundancy and faults is described. Mathematical model to define operation is presented. Schematic circuit diagram of test equipment is provided.
An investigation has been made to determine the effects of noise on human performance. Fourteen subjects performed a memory-decision-response task in relative quiet and while listening to tape recorded noises. Analysis of the data obtained indicates that performance was degraded in the presence of noise. Significant increases in problem solution times were found for impulsive noise conditions as compared with times found for the no-noise condition. Performance accuracy was also degraded. Significantly more error responses occurred at higher noise levels; a direct or positive relation was found between error responses and noise level experienced by the subjects.
Results of investigations using X-ray diffraction and electron-beam microprobe techniques have shown that copper and Permalloy platings interdiffuse at low temperatures when plated-wire memory elements are annealed for times as short as 50 hr. Measurable interdiffusion between Permalloy platings and gold substrates does not occur in similar conditions. Both magnetic and compositional changes during aging are found to occur by a thermally activated process with activation energies around 38 kcal/mol. It is shown, however, that copper-diffusion and magnetic-dispersion changes during aging are merely concurrent processes, neither being the other's cause.
The features of a new class of transparent ferroelectric ceramic materials, called PLZT, are described. PLZT are shown to have very strong electrooptic properties and memory, and are switched through transparent electrodes when mechanically strained. Because of these properties, they can be used to fabricate two-dimensional page composers for coherent optical systems. Techniques for fabricating such devices are outlined along with preliminary test results. Applications in displays are shown to be also feasible.
Self-contained magnetic bubble memory overlay is fabricated by process that employs epitaxial deposition to form multi-layered complex of magnetically active components on single chip. Overlay fabrication comprises three metal deposition steps followed by subtractive etch.
Erasable-memory programs designed for guidance computers used in command and lunar modules are presented. The purpose, functional description, assumptions, restrictions, and imitations are given for each program.
The feasibility of producing a page composer for optical memory systems using thin, deformable, membrane-mirror elements as light valves was investigated. The electromechanical and optical performances of such elements were determined both analytically and experimentally. It was found that fast switching (approximately 10 microseconds), high-contrast (10 or greater), fatigue-free operation over missions of cycles, and efficient utilization of input light could be obtained with membrane light valves. Several arrays of 64 elements were made on substrates with feedthroughs, allowing access to individual elements from the backside of the substrate. Single light valves on such arrays were successfully operated with the transistors designed and produced for selection and storage at each bit location. This simulated the operation of a prototype page composer with semiconductor chips beam-lead bonded to the back of the substrate.