5,329 research outputs found
Evaluation criteria for commercially oriented materials processing in space proposals
An approach and criteria for evaluating NASA funded experiments and demonstrations which have commercial potential were developed. Methods for insuring quick initial screening of commercial proposals are presented. Recommendations are given for modifying the current evaluation approach. New criteria for evaluating commercially orientated materials processing in space (MPS) proposals are introduced. The process for selection of qualified individuals to evaluate the phases of this approach and criteria is considered and guidelines are set for its implementation
Angioneurotic oedema:.a contribution to its historical and clinical study, with special reference to cases recorded as occurring in families
I propose in this Thesis, by a review of its
history, by the presentation of cases of my own observation, and, more especially, by the record and analysi
of cases reported as occurring in families, to show
that where there is an inherited predisposition Angio
neurotic Oedema is indeed a most serious malady, and
that even in other cases it is capable of producing a
much greater amount of bodily discomfort and mental
distress than is commonly supposed
Odonata at a Small Woodland Pond in Southern Illinois
A survey of the adult odonate fauna of a small woodland pond in Pope County, Illinois, was conducted during 1983--·1984. Twenty-four species were collected including Aeshna mutata and Anax longipes. In addition, Libellula vibrans was collected in 1982, and Aeshna sp. (probably u. umbrosa) observed the same year but not collected
Simulation synergy : expanding TRNSYS capabilities and usability
Developers of simulation packages are now able to take advantage of the increase in available desktop computing power to expand the capabilities and usability of their programs. This paper will illustrate these opportunities by discussing the different techniques the developers of the TRNSYS software package have used to try and create a synergy between TRNSYS and external programs and between the developers and users of the program
An evaluation of vibration and other effects on the accuracy of grip and push force recall
Operators of vibratory hand tools can be at risk of developing health problems associated with repeated forceful actions and exposure to intense hand-transmitted vibration. To better assess health risks, comprehensive risk evaluations of these tasks must include quantitative assessments of hand-tool coupling forces. Researchers have used instrumentation for such measurements; but those techniques may be ill-suited for certain field environments. Psychophysical force-recall techniques have been proposed as alternatives to handle instrumentation. This study comprised two experiments that examined the effects of vibration and other factors upon force-recall accuracy and reliability. In each experiment, participants applied specific grip and push forces to an instrumented handle mounted on a shaker system. Participants were exposed to sinusoidal vibration at frequencies that ranged from 0 Hz to 250 Hz. Three levels of applied force and two levels of vibration magnitude were examined. During the vibration exposure period, participants were provided with visual feedback while they attempted to memorize their applied grip and push forces. Following vibration exposure and a rest period, participants tried to duplicate the hand forces without visual feedback. Vibration frequencies, magnitudes, and hand force levels were randomized from trial to trial. To evaluate test-retest reliability, the test was repeated on a later day with each participant. Participants overestimated grip and push forces. Depending on exposure conditions, error means ranged from 2 N to 10 N. The ANOVA revealed that force-recall errors for exposures between 31.5 Hz and 63 Hz were significantly higher than those at other vibration frequencies. Errors were greater when participants were exposed to the higher vibration magnitude when compared with the lower vibration magnitude. The average error for females was significantly less than that for males. The effects of force level were mixed. This method demonstrated strong test-retest reliability as correlations for all but one participant were found to be significant. Overall, recalled force errors were relatively small over the range of operationally-relevant hand-handle coupling forces and vibration exposure conditions. This force-recall technique shows promise as an alternative to expensive and fragile force-sensing instrumentation
Transforming Graph Representations for Statistical Relational Learning
Relational data representations have become an increasingly important topic
due to the recent proliferation of network datasets (e.g., social, biological,
information networks) and a corresponding increase in the application of
statistical relational learning (SRL) algorithms to these domains. In this
article, we examine a range of representation issues for graph-based relational
data. Since the choice of relational data representation for the nodes, links,
and features can dramatically affect the capabilities of SRL algorithms, we
survey approaches and opportunities for relational representation
transformation designed to improve the performance of these algorithms. This
leads us to introduce an intuitive taxonomy for data representation
transformations in relational domains that incorporates link transformation and
node transformation as symmetric representation tasks. In particular, the
transformation tasks for both nodes and links include (i) predicting their
existence, (ii) predicting their label or type, (iii) estimating their weight
or importance, and (iv) systematically constructing their relevant features. We
motivate our taxonomy through detailed examples and use it to survey and
compare competing approaches for each of these tasks. We also discuss general
conditions for transforming links, nodes, and features. Finally, we highlight
challenges that remain to be addressed
On the micro mechanics of one-dimensional normal compression
Discrete-element modelling has been used to investigate the micro mechanics of one-dimensional compression. One-dimensional compression is modelled in three dimensions using an oedometer and a large number of particles, and without the use of agglomerates. The fracture of a particle is governed by the octahedral shear stress within the particle due to the multiple contacts and a Weibull distribution of strengths. Different fracture mechanisms are considered, and the influence of the distribution of fragments produced for each fracture on the global particle size distribution and the slope of the normal compression line is investigated. Using the discrete-element method, compression is related to the evolution of a fractal distribution of particles. The compression index is found to be solely a function of the strengths of the particles as a function of size
Tularemia
John W. McDowell, Harold George Scott, Chester J. Strojanovich, Harry B. Weinburgh."November 1964."Bibliography: p. 72-73
- …