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排序方式: 共有238条查询结果,搜索用时 0 毫秒
41.
42.
Hyland B Svensson CE Ball GC Leslie JR Achtzehn T Albers D Andreoiu C Bricault P Churchman R Cross D Dombsky M Finlay P Garrett PE Geppert C Grinyer GF Hackman G Hanemaayer V Lassen J Lavoie JP Melconian D Morton AC Pearson CJ Pearson MR Phillips AA Schumaker MA Smith MB Towner IS Valiente-Dobón JJ Wendt K Zganjar EF 《Physical review letters》2006,97(10):102501
A high-precision branching ratio measurement for the superallowed beta+ decay of 62Ga was performed at the Isotope Separator and Accelerator radioactive ion beam facility. Nineteen gamma rays emitted following beta+ decay of 62Ga were identified, establishing the dominant superallowed branching ratio to be (99.861+/-0.011)%. Combined with recent half-life and Q-value measurements, this branching ratio yields a superallowed ft value of 3075.6+/-1.4 s for 62Ga decay. These results demonstrate the feasibility of high-precision superallowed branching ratio measurements in the A>or=62 mass region and provide the first stringent tests of the large isospin-symmetry-breaking effects predicted for these decays. 相似文献
43.
We propose a model for unsaturated poro‐plastic flow derived from the thermodynamic principles. For the isothermal case, the problem consists of a degenerate coupled system of two PDEs with two independent hysteresis operators describing hysteresis phenomena in both the solid and the pore fluids. Under natural hypotheses, we prove the existence of a global strong solution for this system. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
44.
Monoamine Oxidase Reporters 1 and 2 (MR1 and MR2) are substrate-tethered activity probes that utilize a tandem amine oxidation/beta-elimination mechanism to detect MAO chemistry in vitro and in living cells directly and specifically without the need for additional enzymes or other activating reagents. 相似文献
45.
Bettina Albers 《PAMM》2009,9(1):507-508
By means of a macroscopic linear model for a poroelastic medium with three deformable components the acoustic behavior of four unconsolidated soil types, filled by water and air, is studied. Necessary material parameters are mainly gathered from the German standard DIN 4220. It provides some useful parameters, as for example, van Genuchten parameters, for thirty-one different soil types including sands, silts and clays. There appear four body waves: three longitudinal waves and one shear wave. The slowest compressional wave does only exist if at least two pore fluids appear and is driven by the capillary pressure between the pore fluids. The wave analysis yields the dependence of velocities and attenuations of these waves on the saturation and on the frequency. This is compared to the so far most frequently studied case of partially saturated sandstones. (© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
46.
This paper addresses how to calculate and interpret the time-delayed mutual information (TDMI) for a complex, diversely and sparsely measured, possibly non-stationary population of time-series of unknown composition and origin. The primary vehicle used for this analysis is a comparison between the time-delayed mutual information averaged over the population and the time-delayed mutual information of an aggregated population (here, aggregation implies the population is conjoined before any statistical estimates are implemented). Through the use of information theoretic tools, a sequence of practically implementable calculations are detailed that allow for the average and aggregate time-delayed mutual information to be interpreted. Moreover, these calculations can also be used to understand the degree of homo or heterogeneity present in the population. To demonstrate that the proposed methods can be used in nearly any situation, the methods are applied and demonstrated on the time series of glucose measurements from two different subpopulations of individuals from the Columbia University Medical Center electronic health record repository, revealing a picture of the composition of the population as well as physiological features. 相似文献
47.
In this article we consider a variant of Rabinowitz Floer homology in order to define a homological count of discriminant points for paths of contactomorphisms. The growth rate of this count can be seen as an analogue of Givental’s nonlinear Maslov index. As an application we prove a Bott–Samelson type obstruction theorem for positive loops of contactomorphisms. 相似文献
48.
Sinusoidal intensity oscillations of the phase conjugated wave reflected from a self-pumped photorefractive BaTiO3 crystal have been observed. The oscillation amplitude is shown to be increased by providing optical feedback of the light scattered during grating formation. The oscillation frequency ? can be tuned from 0.024 Hz to 2 Hz by changing the light intensity I0 of the object beam from 0.7 W/cm2 to 100 W/cm2. A power law ? ∝ Iβ0 ∝ σ with β = 0.89 was observed over this range of intensities (σ = photoconductivity). Transitions to a chaotically oscillating or a stable reflecting state have been observed at higher power levels or with increased optical feedback. An additional pump beam near the entrance face of the signal beam can decrease the build-up time for the self-pumping process by a factor of five or more. 相似文献
49.
Online algorithms: a survey 总被引:5,自引:0,他引:5
Susanne Albers 《Mathematical Programming》2003,97(1-2):3-26
During the last 15 years online algorithms have received considerable research interest. In this survey we give an introduction
to the competitive analysis of online algorithms and present important results. We study interesting application areas and
identify open problems.
Received: December 1, 2002 / Accepted: April 28, 2003
Published online: May 28, 2003
Mathematics Subject Classification (1991): 68W25, 68W40 相似文献
50.
M. Schimmer R. Wirowski S. Albers G. Böhm A. Dewald A. Gelberg P. von Brentano 《Zeitschrift für Physik A Hadrons and Nuclei》1991,338(1):117-118
Yrast as well as non-yrast states of114Sn have been investigated via the100Mo(18O,4n) and the112Cd(,2n) reaction by means of in-beam-ray spectroscopy using the Compton-suppressed germanium detector array OSIRIS-Cube. A new rotational band including the band head with a tentative spin and parity assignment of 5– could be placed in the level scheme and might be a candidate for ag
9
2/–1
h11/2 intruder band. 相似文献