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This report is composed of seven sections. It provides a summary of work accomplished under this contract in several diverse areas of optical transmission, materials processing. The areas include: A description is given of the exp...
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This report is composed of seven sections. It provides a summary of work accomplished under this contract in several diverse areas of optical transmission, materials processing. The areas include: A description is given of the experimental program on the synthesis and single crystal growth of indium phosphide. Device processing techniques covering the use of ultra high vacuum deposition system for evaporating a dielectric layer of silicon monoxide. Materials evaluation techniques under the general heading of electron microscopy. A description is given regarding connecting a two-hidden-layer neural network through an intermediate multiplicative layer showing that it can yield full or partial disambiguities of results from a single 'traditional' neural network. Communication security has been achieved in fiber optic communication systems (IROCS) by ensuring that any undetected intrusion will deliver so little power to a potential intruder that no useful information can be extracted from it. Photorefractive and resonant nonlinear optical interactions are being studied. In this report the requirements of nonlinear optical materials are discussed and fundamental limits are derived. (rrh)
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A need exists for an automated performance test system to study drugs, agents, treatments, and stresses of interest to the aviation, space, and environmental medical community. The purpose of this present study is to evaluate test...
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A need exists for an automated performance test system to study drugs, agents, treatments, and stresses of interest to the aviation, space, and environmental medical community. The purpose of this present study is to evaluate tests for inclusion in the NASA-sponsored Automated Performance Test System (APTS). Twenty-one subjects were tested over 10 replications with tests previously identified as good candidates for repeated-measure research. The tests were concurrently administered in paper-and-pencil and microcomputer modes. Performance scores for the two modes were compared. Data from trials 1 to 10 were examined for indications of test stability and reliability. Nine of the ten APT system tests achieved stability. Reliabilities were generally high. Cross-correlation of microbased tests with traditional paper-and-pencil versions revealed similarity of content within tests in the different modes, and implied at least three cognition and two motor factors. This protable, inexpensive, rugged, computerized battery of tests is recommended for use in repeated-measures studies of environmental and drug effects on performance. Identification of other tests compatible with microcomputer testing and potentially capable of tapping previously unidentified factors is recommended. Documentation of APTS sensitivity to environmental agents is available for more than a dozen facilities and is reported briefly. Continuation of such validation remains critical in establishing the efficacy of APTS tests.
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Alternate forms of the ASVAB were administered five separate times to fifty-seven men and women of military service age. The objective was to determine to what extent means and cross-session correlations are stable over several ad...
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Alternate forms of the ASVAB were administered five separate times to fifty-seven men and women of military service age. The objective was to determine to what extent means and cross-session correlations are stable over several administrations. Ten individual subtests, the derived ASVAB area composites and the Armed Forces Qualification Test (AFQT) were examined for stability. The means for this sample were below the national average and scores were less dispersed. Means increased over sessions .5 standard deviation or more on half the subtests and consequently, on most of the composite scores. Correlations for the subtests and the composites were largely stable over sessions and were slightly higher later in practice. Reliabilities were comparable to reference populations when adjusted for the range restriction of the present sample. The implications of practice effects for paper and pencil as well as automated selection tests are discussed.
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Two information processing tasks were considered for inclusion in a test battery which was being developed for repeated measures investigations of adverse environmental effects. The tests, adapted from the Rose Battery were: Baron...
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Two information processing tasks were considered for inclusion in a test battery which was being developed for repeated measures investigations of adverse environmental effects. The tests, adapted from the Rose Battery were: Baron's Graphemic and Phonemic Analysis, and Posner's Letter Classification. Alternate forms of the the tests were administered on 15 consecutive workdays (Monday to Friday) to 21 Navy enlisted men. A total of 20 measures were taken. These scores were examined to determine when in practice they obtained unchanging or linearly changing means, homogeneous variances, and constant (differentially stable) intertial correlations of an acceptably high level (task definition). In general, correlations of the basic measures tended to become stable with sufficient practice, but derived measures such as difference, slope, and ratio scores did not attain stability. The Baron and Posner tasks had high reliabilities and were highly correlated with each other. Preliminary analysis indicated that both tests may be measuring the same thing. Either the Baron Sense/Nonsense or the Posner Name score may be recommended for repeated measures experimentation.
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The overall impression is of a learning curve which may not be level by Day 15. The means range from 4.38 to 6.75 while the standard deviations vary from .62 to .95. An analysis of variance conducted on the data revealed practice ...
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The overall impression is of a learning curve which may not be level by Day 15. The means range from 4.38 to 6.75 while the standard deviations vary from .62 to .95. An analysis of variance conducted on the data revealed practice and subjects effects. The correlations deserve special mention: The average of the test-retest correlations for Days 1 - 5 is .639; for Days 6 - 10, .767; and for Days 11 - 15, .831. Figure 2 shows correlation coefficients of Days 1, 2, 4, 9 and 13 with the days which followed. A generally declining function is evident which is similar to those previously reported, e.g., by Jones.
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Three sea going vessels steamed side-by-side through slight seas off the coast of Oahu, Hawaii. A four-hour octagon was transitted twice each day for three consecutive days while motion sickness symptomatology was recorded from ei...
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Three sea going vessels steamed side-by-side through slight seas off the coast of Oahu, Hawaii. A four-hour octagon was transitted twice each day for three consecutive days while motion sickness symptomatology was recorded from eighteen enlisted men who alternated among the vessels. Dramatic differences in illness severity were obtained whether comparisons were made using objective evidence of vomiting episodes or subjective reporting of symptoms on questionnaires. Reliability of this scoring method was excellent (r = .95). In addition to face and construct validity, evidence is presented of the predictive validity of the scoring method in a separate octogonal steaming experiment; using a 95 ft. Coast Guard Patrol Boat in an equivalent experimental paradigm. This study showed significant covariance between the magnitude of motion sickness symptomatology and the encounter direction of the vessel to the primary swell (p less than .01). Additional, significant correlations were found between sickness severity and test subject concentration, fatigue, urine production and urine specific gravity. The majority of these relationships would not have been disclosed had only the dichotomous criterion of vomit/nonvomit been employed in assessing motion sickness severity. Implications of these data as design criteria for marine vehicles are discussed. (Author)
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The present report focuses on the reliability and validity of combining subjective reports of symptomatology with objective reports of vomiting by experimenters in an expanded scale for motion sickness severity assessment.
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The problem of specifying the optimum quantum detector in multiple hypotheses testing is considered for application to optical communications. The quantum digital detection problem is formulated as a linear programming problem on ...
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The problem of specifying the optimum quantum detector in multiple hypotheses testing is considered for application to optical communications. The quantum digital detection problem is formulated as a linear programming problem on an infinite-dimensional space. A necessary and sufficient condition is derived by the application of a general duality theorem specifying the optimum detector in terms of a set of linear operator equations and inequalities. Existence of the optimum quantum detector is also established. The optimality of commuting detection operators is discussed in some examples. The structure and performance of the optimal receiver are derived for the quantum detection of narrow-band coherent orthogonal and simplex signals. It is shown that modal counting is asymptotically optimum in the limit of a large signaling alphabet and that the capacity goes to infinity in the absence of a bandwidth limitation. (Author)
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Topics included are: Optical communications, Oscillators, Mixers, Telecommunications; Memories, Recording and Displays; Optical filtering, Holography, Pattern recognition; Optical processing in real time, Radar signal processing, ...
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Topics included are: Optical communications, Oscillators, Mixers, Telecommunications; Memories, Recording and Displays; Optical filtering, Holography, Pattern recognition; Optical processing in real time, Radar signal processing, Applications of lasers.
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