19,985 research outputs found
Slide rule-type color chart predicts reproduced photo tones
Slide rule-type color chart determines the final reproduced gray tones in the production of briefing charts that are photographed in black and white. The chart shows both the color by drafting paint manufacturers name and mixture number, and the gray tone resulting from black and white photographic reproduction
Fermionic Field Theory and Gauge Interactions on Random Lattices
Random-lattice fermions have been shown to be free of the doubling problem if
there are no interactions or interactions of a non-gauge nature. However, gauge
interactions impose stringent constraints as expressed by the Ward-Takahashi
identities which could revive the free-field suppressed doubler modes in loop
diagrams. After introducing a formulation for fermions on a new kind of random
lattice, we compare random, naive and Wilson fermions in two dimensional
Abelian background gauge theory. We show that the doublers are revived for
random lattices in the continuum limit, while demonstrating that gauge
invariance plays the critical role in this revival. Some implications of the
persistent doubling phenomenon on random lattices are also discussed.Comment: 16 A4 pages, UM-P-93/0
Simulations with Complex Measures
Towards a solution to the sign problem in the simulations of systems having
indefinite or complex-valued measures, we propose a new approach which yields
statistical errors smaller than the crude Monte Carlo using absolute values of
the original measures. The 1D complex-coupling Ising model is employed as an
illustration.Comment: 3 pages, postcript (95K), contribution to LAT93, UM-P-93/10
Influence of facemask design on operational performance
Spirometric measurements of oxygen volume and determination of the amount of argon in exhaled breath are used to analyze facemask design efficiency during treadmill walking tests with subjects carrying plastic hoods filled with argon. Facemask leakage measurements established the better performance of a pneumatic seal type mask in comparison with plain seal type masks
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When users control the algorithms: Values expressed in practices on the twitter platform
Recent interest in ethical AI has brought a slew of values, including fairness, into conversations about technology design. Research in the area of algorithmic fairness tends to be rooted in questions of distribution that can be subject to precise formalism and technical implementation. We seek to expand this conversation to include the experiences of people subject to algorithmic classification and decision-making. By examining tweets about the “Twitter algorithm” we consider the wide range of concerns and desires Twitter users express. We find a concern with fairness (narrowly construed) is present, particularly in the ways users complain that the platform enacts a political bias against conservatives. However, we find another important category of concern, evident in attempts to exert control over the algorithm. Twitter users who seek control do so for a variety of reasons, many well justified. We argue for the need for better and clearer definitions of what constitutes legitimate and illegitimate control over algorithmic processes and to consider support for users who wish to enact their own collective choices
Mixed Quantum/Classical Theory of Rotationally and Vibrationally Inelastic Scattering in Space-fixed and Body-fixed Reference Frames
We formulated the mixed quantum/classical theory for rotationally and vibrationally inelastic scattering process in the diatomic molecule + atom system. Two versions of theory are presented, first in the space-fixed and second in the body-fixed reference frame. First version is easy to derive and the resultant equations of motion are transparent, but the state-to-state transition matrix is complex-valued and dense. Such calculations may be computationally demanding for heavier molecules and/or higher temperatures, when the number of accessible channels becomes large. In contrast, the second version of theory requires some tedious derivations and the final equations of motion are rather complicated (not particularly intuitive). However, the state-to-state transitions are driven by real-valued sparse matrixes of much smaller size. Thus, this formulation is the method of choice from the computational point of view, while the space-fixed formulation can serve as a test of the body-fixed equations of motion, and the code. Rigorous numerical tests were carried out for a model system to ensure that all equations, matrixes, and computer codes in both formulations are correct
Research and development in cds photovoltaic film cells third quarterly report, nov. 19, 1964 - feb. 19, 1965
Cadmium sulfide photovoltaic film cell
Research and development in cds photovoltaic film cells final report
Fabrication of lightweight, flexible, high efficiency, low cost, thin film, cadmium sulfide solar cells to operate for long periods in space without appreciable degradatio
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