42,332 research outputs found
Immunoadsorbents - Preparation and use of cellulose derivatives
Antibody isolation from blood by linking antigens to insoluble cellulose derivative
Tree-oriented interactive processing with an application to theorem-proving, appendix E
The concept of unstructured structure editing and ted, an editor for unstructured trees, is described. Ted is used to manipulate hierarchies of information in an unrestricted manner. The tool was implemented and applied to the problem of organizing formal proofs. As a proof management tool, it maintains the validity of a proof and its constituent lemmas independently from the methods used to validate the proof. It includes an adaptable interface which may be used to invoke theorem provers and other aids to proof construction. Using ted, a user may construct, maintain, and verify formal proofs using a variety of theorem provers, proof checkers, and formatters
Self-recording portable soil penetrometer
A lightweight portable penetrometer for testing soil characteristics is described. The penetrometer is composed of a handle, data recording, and probe components detachably joined together. The data recording component has an easily removed recording drum which rotates according to the downward force applied on the handle, and a stylus means for marking the drum along its height according to the penetration depth of probe into the soil
Does the Sun shrink with increasing magnetic activity?
It has been demonstrated that frequencies of f-modes can be used to estimate
the solar radius to a good accuracy. These frequencies have been used to study
temporal variations in the solar radius with conflicting results. The variation
in f-mode frequencies is more complicated than what is assumed in these
studies. If a careful analysis is performed then it turns out that there is no
evidence for any variation in the solar radius.Comment: To appear in Astrophys.
Reply to Comment on "Quantum phase transition in the four-spin exchange antiferromagnet"
We argue that our analysis of the J-Q model, presented in Phys. Rev. B 80,
174403 (2009), and based on a field-theory description of coupled dimers,
captures properly the strong quantum fluctuations tendencies, and the
objections outlined by L. Isaev, G. Ortiz, and J. Dukelsky, arXiv:1003.5205,
are misplaced
Stochastic modelling of intermittent scrape-off layer plasma fluctuations
Single-point measurements of fluctuations in the scrape-off layer of
magnetized plasmas are generally found to be dominated by large-amplitude
bursts which are associated with radial motion of blob-like structures. A
stochastic model for these fluctuations is presented, with the plasma density
given by a random sequence of bursts with a fixed wave form. Under very general
conditions, this model predicts a parabolic relation between the skewness and
kurtosis moments of the plasma fluctuations. In the case of exponentially
distributed burst amplitudes and waiting times, the probability density
function for the fluctuation amplitudes is shown to be a Gamma distribution
with the scale parameter given by the average burst amplitude and the shape
parameter given by the ratio of the burst duration and waiting times.Comment: 11 pages, 1 figur
Congruent families and invariant tensors
Classical results of Chentsov and Campbell state that -- up to constant
multiples -- the only -tensor field of a statistical model which is
invariant under congruent Markov morphisms is the Fisher metric and the only
invariant -tensor field is the Amari-Chentsov tensor. We generalize this
result for arbitrary degree , showing that any family of -tensors which
is invariant under congruent Markov morphisms is algebraically generated by the
canonical tensor fields defined in an earlier paper
Estimating Lunar Pyroclastic Deposit Depth from Imaging Radar Data: Applications to Lunar Resource Assessment
Lunar pyroclastic deposits represent one of the primary anticipated sources of raw materials for future human settlements. These deposits are fine-grained volcanic debris layers produced by explosive volcanism contemporaneous with the early stage of mare infilling. There are several large regional pyroclastic units on the Moon (for example, the Aristarchus Plateau, Rima Bode, and Sulpicius Gallus formations), and numerous localized examples, which often occur as dark-halo deposits around endogenic craters (such as in the floor of Alphonsus Crater). Several regional pyroclastic deposits were studied with spectral reflectance techniques: the Aristarchus Plateau materials were found to be a relatively homogeneous blanket of iron-rich glasses. One such deposit was sampled at the Apollo 17 landing site, and was found to have ferrous oxide and titanium dioxide contents of 12 percent and 5 percent, respectively. While the areal extent of these deposits is relatively well defined from orbital photographs, their depths have been constrained only by a few studies of partially filled impact craters and by imaging radar data. A model for radar backscatter from mantled units applicable to both 70-cm and 12.6-cm wavelength radar data is presented. Depth estimates from such radar observations may be useful in planning future utilization of lunar pyroclastic deposits
A note on a result of Liptser-Shiryaev
Given two stochastic equations with different drift terms, under very weak
assumptions Liptser and Shiryaev provide the equivalence of the laws of the
solutions to these equations by means of Girsanov transform. Their assumptions
involve both the drift terms. We are interested in the same result but with the
main assumption involving only the difference of the drift terms. Applications
of our result will be presented in the finite as well as in the infinite
dimensional setting.Comment: 22 pages; revised and enlarged versio
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