61,453 research outputs found
Consenting agents: semi-autonomous interactions for ubiquitous consent
Ubiquitous computing, given a regulatory environment that seems to favor consent as a way to empower citizens, introduces the possibility of users being asked to make consent decisions in numerous everyday scenarios such as entering a supermarket or walking down the street. In this note we outline a model of semi-autonomous consent (SAC), in which preference elicitation is decoupled from the act of consenting itself, and explain how this could protect desirable properties of informed consent without overwhelming users. We also suggest some challenges that must be overcome to make SAC a reality
Nuclear fusion induced by X-rays in a crystal
The nuclei that constitute a crystalline lattice, oscillate relative to each
other with a very low energy that is not sufficient to penetrate through the
Coulomb barriers separating them. An additional energy, which is needed to
tunnel through the barrier and fuse, can be supplied by external
electromagnetic waves (X-rays or the synchrotron radiation). Exposing to the
X-rays the solid compound LiD (lithium-deuteride) for the duration of 111
hours, we have detected 88 events of the nuclear fusion d+Li6 ---> Be8*. Our
theoretical estimate agrees with what we observed. One of possible applications
of the phenomenon we found, could be the measurements of the rates of various
nuclear reactions (not necessarily fusion) at extremely low energies
inaccessible in accelerator experiments.Comment: 27 pages, 12 figures; submitted to Phys. Rev. C on 28 October 201
Separation of variables and the XXZ Gaudin magnet
In this work we generalise previous results connecting (rational) Gaudin
magnet models and classical separation of variables. It is shown that the
connection persists for the case of linear r-matrix algebra which corresponds
to the trigonometric 4x4 r-matrix (of the XXZ type). We comment also on the
corresponding problem for the elliptic (XYZ) r-matrix. A prescription for
obtaining integrable systems associated with multiple poles of an L-operator is
given.Comment: 11 pages, AMS-Te
Quasicontinuum Models of Interfacial Structure and Deformation
Microscopic models of the interaction between grain boundaries (GBs) and both
dislocations and cracks are of importance in understanding the role of
microstructure in altering the mechanical properties of a material. A recently
developed mixed atomistic and continuum method is extended to examine the
interaction between GBs, dislocations and cracks. These calculations elucidate
plausible microscopic mechanisms for these defect interactions and allow for
the quantitative evaluation of critical parameters such as the stress to
nucleate a dislocation at a step on a GB and the force needed to induce GB
migration.Comment: RevTex, 4 pages, 4 figure
Handling the Handbag Diagram in Compton Scattering on the Proton
Poincare invariance, gauge invariance, conservation of parity and time
reversal invariance are respected in an impulse approximation evaluation of the
handbag diagram. Proton wave functions, previously constrained by comparison
with measured form factors, that incorporate the influence of quark transverse
and orbital angular momentum (and the corresponding violation of proton
helicity conservation) are used. Computed cross sections are found to be in
reasonably good agreement with early measurements. The helicity correlation
between the incident photon and outgoing proton, , is both large and
positive at back angles. For photon laboratory energies of 6 GeV, we find
that , , and that the polarization can be
large.Comment: 9 pages, 6 figures. Replacement fixes some typos, improves references
and figures. An error in Fig. 6 was corrected and related comments in the
text change
Use of phytochrome-dependent reaction in evaluating the effect of space flight factors on the plant organism
The effects of space flight factors on lettuce seeds aboard the Kosmos-936 and Kosmos-1129 satellites for 20 days were studied. The phytochrome dependent (PD) reaction of light sensitive seeds was a sensitive criterion for evaluating the biological effects of space flight factors. The PD reaction of air dry lettuce seeds was suppressed after space flight, especially if the seeds were exposed to open space during the flight. Space flight affects the physiological activity of both phytochrome forms, and both the phi sub 730 dependent reactions of lettuce seeds were suppressed
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