388 research outputs found
Investigation of effects of ablative discrepancies on nozzle performance reliability Final report
Effects of ablative discrepancies on nozzle performance reliabilit
Optical Flow on Evolving Surfaces with an Application to the Analysis of 4D Microscopy Data
We extend the concept of optical flow to a dynamic non-Euclidean setting.
Optical flow is traditionally computed from a sequence of flat images. It is
the purpose of this paper to introduce variational motion estimation for images
that are defined on an evolving surface. Volumetric microscopy images depicting
a live zebrafish embryo serve as both biological motivation and test data.Comment: The final publication is available at link.springer.co
An elementary method of calculating an explicit form of Young measures in some special cases
We present an elementary method of explicit calculation of Young measures for
certain class of functions. This class contains in particular functions of a
highly oscillatory nature which appear in optimization problems and
homogenization theory. In engineering such situation occurs for instance in
nonlinear elasticity (solid-solid phase transition in certain elastic
crystals). Young measures associated with oscillating minimizing sequences
gather information about their oscillatory nature and therefore about
underlying microstructure. The method presented in the paper makes no use of
functional analytic tools. There is no need to use generalized version of the
Riemann {Lebesgue lemma and to calculate weak* limits of functions. The main
tool is the change of variable theorem. The method applies both to sequences of
periodic and nonperiodic functions.Comment: 11 pages, no figures An article in its new version due to the
reviewers' remarks. All the results stated and proved in multidimensional
version; corrected innacuracie
A Chebyshev minimax technique oriented to aerospace trajectory optimization problems.
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76822/1/AIAA-6604-910.pd
Second-order necessary conditions in optimal control: Accessory-problem results without normality conditions
An optimal control problem, which includes restrictions on the controls and equality/inequality constraints on the terminal states, is formulated. Second-order necessary conditions of the accessory-problem type are obtained in the absence of normality conditions. It is shown that the necessary conditions generalize and simplify prior results due to Hestenes (Ref. 5) and Warga (Refs. 6 and 7).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45219/1/10957_2004_Article_BF00934437.pd
The effect of chewing gum on physiological and self-rated measures of alertness and daytime sleepiness
The proposition that chewing gum can improve alertness was investigated via both physiological and self-rated measures. The Pupillographic Sleepiness Test (PST) provided a measure of pupillary unrest (PUI); a physiological index of daytime sleepiness. Chewing gum reduced the extent of sleepiness as measured by both PUI and self-rated sleepiness. Specifically, in comparison with sham chewing and no chewing controls, the chewing gum condition significantly limited the increase in pupillary unrest following the 11-minute PST within a darkened laboratory: a finding indicating moderation of the daytime sleepiness increase for the chewing gum condition. In addition, there was some evidence that chewing gum (relative to the no-chewing condition only) moderated the increase in a self-rated measure of sleepiness (Stanford Sleepiness Scale). However, there was no evidence that chewing gum moderated the decrease in self-rated alertness (Bond-Lader Visual Analogue Mood Scale). Although the precise mechanism underpinning the effect of chewing gum is unclear, the reduction in daytime sleepiness may be underpinned via heightened cerebral activity following the chewing of gum or the arousing effects of mint flavour
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