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661.
Benjamini asked whether the scenery reconstruction methods of Matzinger (see e.g. [21], [22], [20]) can be done in polynomial
time. In this article, we give the following answer for a 2-color scenery and simple random walk with holding: We prove that
a piece of the scenery of length of the order 3
n
around the origin can be reconstructed – up to a reflection and a small translation – with high probability from the first
2 · 310
αn
observations with a constant α > 0 independent of n. Thus, the number of observations needed is polynomial in the length of the piece of scenery which we reconstruct. The probability
that the reconstruction fails tends to 0 as n→∞.
In contrast to [21], [22], and [20], the proofs in this article are all constructive. Our reconstruction algorithm is an algorithm
in the sense of computer science. This is the first article which shows that the scenery reconstruction is also possible in
the 2-color case with holding. The case with holding is much more difficult than [22] and requires completely different methods. 相似文献
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Schwoerer H Gibbon P Düsterer S Behrens R Ziener C Reich C Sauerbrey R 《Physical review letters》2001,86(11):2317-2320
We demonstrate a novel method to monitor the total angular distribution of the spectrum of hard x-ray emission from a plasma generated with femtosecond laser pulses with an intensity of 5 x 10(18) W/cm2 on a solid target. Measured and calculated angular distributions of x rays show a pronounced anisotropy for MeV photon energies. We complemented the spectral information by demonstrating a (gamma,n) nuclear reaction with a tabletop laser system. 相似文献
669.
Silke Kaske Gabriele Krasteva Peter König Wolfgang Kummer Thomas Hofmann Thomas Gudermann Vladimir Chubanov 《BMC neuroscience》2007,8(1):49
Background
A growing number of TRP channels have been identified as key players in the sensation of smell, temperature, mechanical forces and taste. TRPM5 is known to be abundantly expressed in taste receptor cells where it participates in sweet, amino acid and bitter perception. A role of TRPM5 in other sensory systems, however, has not been studied so far. 相似文献670.
Christian Balischewski Dr. Karsten Behrens Dr. Kerstin Zehbe Dr. Christina Günter Stefan Mies Dr. Eric Sperlich Alexandra Kelling Prof. Dr. Andreas Taubert 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(72):17504-17513
Thirteen N-butylpyridinium salts, including three monometallic [C4Py]2[MCl4], nine bimetallic [C4Py]2[M1−xaMxbCl4] and one trimetallic compound [C4Py]2[M1−y-zaMybMzcCl4] (M=Co, Cu, Mn; x=0.25, 0.50 or 0.75 and y=z=0.33), were synthesized and their structure and thermal and electrochemical properties were studied. All compounds are ionic liquids (ILs) with melting points between 69 and 93 °C. X-ray diffraction proves that all ILs are isostructural. The conductivity at room temperature is between 10−4 and 10−8 S cm−1. Some Cu-based ILs reach conductivities of 10−2 S cm−1, which is, however, probably due to IL dec. This correlates with the optical bandgap measurements indicating the formation of large bandgap semiconductors. At elevated temperatures approaching the melting points, the conductivities reach up to 1.47×10−1 S cm−1 at 70 °C. The electrochemical stability windows of the ILs are between 2.5 and 3.0 V. 相似文献