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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Fab-dimerized glycan-reactive antibodies are a structural category of natural antibodies
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Managed Category for Construction (MCC) On-Boarding: Part 1 [Slides]
Abstract not provided.
Managed Category for Construction (MCC) On Boarding: Part 2 - The Master Contract [Slides]
Abstract not provided.
Adversarial Machine Learning: Categories, Concepts, and Current Landscape
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A Computational Theory for the Emergence of Grammatical Categories in Cortical Dynamics
A general agreement in psycholinguistics claims that syntax and meaning are unified precisely and very quickly during online sentence processing. Although several theories have advanced arguments regarding the neurocomputational bases of this phenomenon, we argue that these theories could potentially benefit by including neurophysiological data concerning cortical dynamics constraints in brain tissue. In addition, some theories promote the integration of complex optimization methods in neural tissue. In this paper we attempt to fill these gaps introducing a computational model inspired in the dynamics of cortical tissue. In our modeling approach, proximal afferent dendrites produce stochastic cellular activations, while distal dendritic branches–on the other hand–contribute independently to somatic depolarization by means of dendritic spikes, and finally, prediction failures produce massive firing events preventing formation of sparse distributed representations. The model presented in this paper combines semantic and coarse-grained syntactic constraints for each word in a sentence context until grammatically related word function discrimination emerges spontaneously by the sole correlation of lexical information from different sources without applying complex optimization methods. By means of support vector machine techniques, we show that the sparse activation features returned by our approach are well suited—bootstrapping from the features returned by Word Embedding mechanisms—to accomplish grammatical function classification of individual words in a sentence. In this way we develop a biologically guided computational explanation for linguistically relevant unification processes in cortex which connects psycholinguistics to neurobiological accounts of language. We also claim that the computational hypotheses established in this research could foster future work on biologically-inspired learning algorithms for natural language processing applications.
Absolute judgment of more than 32 categories /5 bits/ with a unidimensional visual stimulus.
Stimuli human subjects can identify on unidimensional visual stimulus continuum, discussing apparatus and line length influence
Testing on G and N non-metallic materials in an oxygen atmosphere - Categories B, E, F, and H Final report
Flammability tests of guidance and navigation nonmetallic materials in pure oxygen atmosphere
External insulation systems for cryogenic storage systems - Bibliography/synopsis and category report /type 2 data/
Bibliography synopsis of external insulation materials and techniques for cryogenic storage systems
Effect of commercial and military performance requirements for transport category aircraft on space shuttle booster design and operation
The effect of two sets of performance requirements, commercial and military, on the design and operation of the space shuttle booster is evaluated. Critical thrust levels are established according to both sets of operating rules for the takeoff, cruise, and go-around flight modes, and the effect on engine requirements determined. Both flyback and ferry operations are considered. The impact of landing rules on potential shuttle flyback and ferry bases is evaluated. Factors affecting reserves are discussed, including winds, temperature, and nonstandard flight operations. Finally, a recommended set of operating rules is proposed for both flyback and ferry operations that allows adequate performance capability and safety margins without compromising design requirements for either flight phase.
A comparison of two approaches for category identification and classification analysis from an agricultural scene
Supervised and unsupervised classification modes are discussed in light of the multidisciplinary, high data rate requirements of the ERTS satellites soon to be launched. Inadequacies of each system in light of these requirements are noted and a compromise solution to the data classification system is proposed. An example of results obtained with an implementation of this system are shown and compared with results from a supervised classification scheme.
Determination of ILS category 2 decision height window requirements
A method for determining the appropriate longitudinal and lateral decision height dispersion limits for any airplane/control system combination during an instrument landing approach is presented. An example is worked out to clarify the steps required. It is shown that the current longitudinal decision height dispersion limits are well suited for a DC-8 with the example control system, but that the lateral limits are too loose to guarantee acceptable touchdowns with the example system subjected to recommended wind and shear disturbances.
Area measurement of land use categories in Finney County, Kansas
There are no author-identified significant results in this report.
A comparison of two approaches for category identification and classification analysis from an agricultural scene.
Supervised and unsupervised classification modes are discussed in light of the multidisciplinary, high data rate requirements of the ERTS satellites soon to be launched. Inadequacies of each system in light of these requirements are noted and a compromise solution to the data classification system is proposed. An example of results obtained with an implementation of this system are shown and compared with results from a supervised classification scheme.
Thirteen category recognition map of Yellowstone National Park produced from ERTS-1 MSS data
There are no author-identified significant results in this report.
Simulation study of intracity helicopter operations under instrument conditions to category 1 minimums
A fixed-base simulator study was conducted to define pilot workload and task performance associated with instrument flight operations for an intracity helicopter passenger service. Displays considered necessary to provide a minimal capability under Instrument Flight Rules conditions were used to fly a representative commercial helicopter route structure in the New York area, with each terminal assumed to be equipped with a precision approach guidance system. A cross section of pilots participated as test subjects, and despite the high workload level, the results indicated that for the assumptions employed, minimums of 61 m (200 ft) ceiling and 805 m (0.5 mile) visibility were feasible.