1,622 research outputs found
Sweat collection capsule
A sweat collection capsule permitting quantitative collection of sweat is described. The device consists of a frame held immobile on the skin, a closure secured to the frame and absorbent material located next to the skin in a cavity formed by the frame and the closure. The absorbent material may be removed from the device by removing the closure from the frame while the frame is held immobile on the skin
Electromagnetic wormholes via handlebody constructions
Cloaking devices are prescriptions of electrostatic, optical or
electromagnetic parameter fields (conductivity , index of refraction
, or electric permittivity and magnetic permeability
) which are piecewise smooth on and singular on a
hypersurface , and such that objects in the region enclosed by
are not detectable to external observation by waves. Here, we give related
constructions of invisible tunnels, which allow electromagnetic waves to pass
between possibly distant points, but with only the ends of the tunnels visible
to electromagnetic imaging. Effectively, these change the topology of space
with respect to solutions of Maxwell's equations, corresponding to attaching a
handlebody to . The resulting devices thus function as
electromagnetic wormholes.Comment: 25 pages, 6 figures (some color
New system for bathing bedridden patients
Multihead shower facility can be used with minimal patient handling. Waterproof curtain allows patient to bathe with his head out of shower. He can move completely inside shower to wash his face and hair. Main advantage of shower system is time saved in giving bath
Human acclimation and acclimatization to heat: A compendium of research, 1968-1978
Abstracts and annotations of the majority of scientific works that elucidate the mechanisms of short-term acclimation to heat in men and women are presented. The compendium includes material from 1968 through 1977. Subject and author indexes are provided and additional references of preliminary research findings or work of a peripheral nature are included in a bibliography
Physiological responses to prolonged bed rest in humans: A compendium of research, 1981-1988
Clinical observations and results form more basic studies that help to elucidate the physiological mechanisms of the adaptation of humans to prolonged bed rest. If the authors' abstract or summary was appropriate, it was included. In some cases a more detailed synopsis was provided under the subheadings of purpose, methods, results, and conclusions
Electromagnetic analysis of arbitrarily shaped pinched carpets
We derive the expressions for the anisotropic heterogeneous tensors of
permittivity and perme- ability associated with two-dimensional and
three-dimensional carpets of an arbitrary shape. In the former case, we map a
segment onto smooth curves whereas in the latter case we map a non convex
region of the plane onto smooth surfaces. Importantly, these carpets display no
singularity of the permeability and permeability tensor components, and this
may lead to some broadband cloaking.Comment: 6 pages, 6 figures, Current Status of Manuscript: 19Apr10
26May10-Sent on appeal;report rcvd 29Dec09 13Apr10-Ed. decision and/or ref.
comments to author;response rcvd 04Dec09 21Dec09-Ed. decision and/or ref.
comments to author;response rcvd 01Dec09-Transferred from PRL to PRA 18Aug09
30Nov09-Ed.decision and/or ref. comments to author;response rcvd 14Aug09 -
Correspondence sent to autho
Full-wave invisibility of active devices at all frequencies
There has recently been considerable interest in the possibility, both
theoretical and practical, of invisibility (or "cloaking") from observation by
electromagnetic (EM) waves. Here, we prove invisibility, with respect to
solutions of the Helmholtz and Maxwell's equations, for several constructions
of cloaking devices. Previous results have either been on the level of ray
tracing [Le,PSS] or at zero frequency [GLU2,GLU3], but recent numerical [CPSSP]
and experimental [SMJCPSS] work has provided evidence for invisibility at
frequency . We give two basic constructions for cloaking a region
contained in a domain from measurements of Cauchy data of waves at \p
\Omega; we pay particular attention to cloaking not just a passive object, but
an active device within , interpreted as a collection of sources and sinks
or an internal current.Comment: Final revision; to appear in Commun. in Math. Physic
Inverse problems with partial data for a magnetic Schr\"odinger operator in an infinite slab and on a bounded domain
In this paper we study inverse boundary value problems with partial data for
the magnetic Schr\"odinger operator. In the case of an infinite slab in ,
, we establish that the magnetic field and the electric potential can
be determined uniquely, when the Dirichlet and Neumann data are given either on
the different boundary hyperplanes of the slab or on the same hyperplane. This
is a generalization of the results of [41], obtained for the Schr\"odinger
operator without magnetic potentials. In the case of a bounded domain in ,
, extending the results of [2], we show the unique determination of the
magnetic field and electric potential from the Dirichlet and Neumann data,
given on two arbitrary open subsets of the boundary, provided that the magnetic
and electric potentials are known in a neighborhood of the boundary.
Generalizing the results of [31], we also obtain uniqueness results for the
magnetic Schr\"odinger operator, when the Dirichlet and Neumann data are known
on the same part of the boundary, assuming that the inaccessible part of the
boundary is a part of a hyperplane
Estimation and Analysis of Atmospheric Vortices
ESTIMATION AND ANALYSIS OF ATMOSPHERIC VORTICESLynn GreenleafUniversity of Oklahoma([email protected])Intense atmospheric vortices occur in dust devils, waterspouts, tornadoes, mesocyclones and tropical cyclones. Tangential wind models have been proposed that approximate the observed tangential wind profile of at atmospheric vortex for the purpose of data analysis and prediction. Data analysis is required to demonstrate in an objective way that a parameterized tangential wind model provides an acceptable desciption of the tangential wind profile of an atmospheric vortex and determine if the model can be used to make accurate predictions. Analysis of the residuals indicates that nonlinear least squares analysis is appropriate. The Wood-White 2 vortex model provides good approximations to the benchmark Davies-Jones data set in radial, tangential and vertical wind estimates. Using the methodology of Information Theory and Sensitivity Analysis, information content of the parameters of the Wood-White 2 vortex model show that both parameters are essential in estimation of the tangential wind profile. The variances in both parameters were large, but can be reduced by using random samples containing the statistical properties of the data. The Local Sensitivity Analysis method can be used without much loss of information which will be valuable in the analysis of models with a large number of parameters. Uncertainty in radial, tangential and vertical winds were examined and can be used effectively to predict these quantiies and their uncertainties
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