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991.
Excitation functions of the analyzing power in elastic proton-proton scattering from 0.45 to 2.5 GeV
M. Altmeier F. Bauer J. Bisplinghoff K. Büßer M. Busch T. Colberg L. Demirörs H. P. Engelhardt P. D. Eversheim K. O. Eyser O. Felden R. Gebel M. Glende J. Greiff F. Hinterberger E. Jonas H. Krause T. Lindemann J. Lindlein B. Lorentz R. Maier R. Maschuw A. Meinerzhagen D. Prasuhn H. Rohdjeß D. Rosendaal P. von Rossen N. Schirm V. Schwarz W. Scobel H. -J. Trelle K. Ulbrich E. Weise A. Wellinghausen R. Ziegler 《The European Physical Journal A - Hadrons and Nuclei》2005,23(2):351-364
Excitation functions AN(plab,c.m.) of the analyzing power in elastic proton-proton scattering have been measured in an internal target experiment at the Cooler Synchrotron COSY with an unpolarized proton beam and a polarized atomic hydrogen target. Data were taken continuously during the acceleration and deceleration for proton kinetic energies Tlab (momenta plab) between 0.45 and 2.5 GeV (1.0 and 3.3 GeV/c) and scattering angles 30 ° c.m. 90°. The results provide excitation functions and angular distributions of high precision and internal consistency. The data can be used as calibration standard between 0.45 and 2.5 GeV. They have significant impact on phase shift solutions, in particular on the spin triplet phase shifts between 1.0 and 1.8 GeV. 相似文献
992.
Ann M. Hentschel 《Physics in Perspective (PIP)》2005,7(1):107-129
This tour of significant scientific sites in Bern uses the local legacy of its most illustrious scientists, Albert Einstein (1879–1955) and Fritz Houtermans (1903–1966), as its guiding thread through the old town and the university district.Ann M.Hentschel is translator of the correspondence volumes of The Collected Papers of Albert Einstein and is currently employed by the Institute for the History and Philosophy of Science at the University of Bern to write the guide for a city tour of Einsteins old haunts in Bern for the coming jubilee of special relativity in 2005. For the historical companion guidebook, see Hentschel and Grasshoff, Albert Einstein (ref. 4) and the website <. 相似文献
993.
LI Zhihui ZHANG Hanxin & FU Song ⒈ National Laboratory for CFD Hypervelocity Aerodynamics Institute China Aerodynamics Research Development Center Mianyang China .Department of Engineering Mechanics Tsinghua University Beijing China 《中国科学G辑(英文版)》2005,48(4):496-512
~~Gas kinetic algorithm for flows in Poiseuille-like microchannels using Boltzmann model equation1. Feynman, R., There's plenty of room at the bottom, Journal of Microelectromechanical Systems, 1992, 1: 60 -66.
2. Piekos, E. S., Breuer, K. S., Numerical modeling of micromechanical devices using the direct simulation Monte Carlo method, Transactions of the ASME, Journal of Fluids Engineering, 1996, 118: 464-469.
3. Beskok, A., Karniadakis, G. E., Trimmer, W., Rarefaction and … 相似文献
994.
** Email: giorgio.vittadini{at}unimib.it*** Email: simona.minotti{at}unicatt.it In this paper we propose a methodology for measuring the relativeeffectiveness of healthcare services (i.e. the effectof hospital care on patients) under general conditions, in which:) a healthcare outcome underlies qualitative and quantitativeobservable indicators; ß) we are interested in studyingthe simultaneous dependency of multiple outcomes on covariates(where the outcomes can also be correlated to each other); )the relative effectiveness is adjusted for hospital-specificcovariates; ) we hypothesise a general distribution for randomdisturbances and the random parameters of relative effectiveness.For this topic, a generalisation of the SURE (seemingly unrelatedregression equations) multilevel model is proposed. The solutionsare obtained by means of Bayesian inference methods. Since thereis currently no software available to estimate this model, anSAS procedure based on Markov Chain Monte Carlo methods hasbeen developed by the authors, in line with Goldstein &Spiegelhalter (1996, J. R. Stat. Soc. Ser. A, 159, 385443),Spiegelhalter et al. (1996, Bayesian Using Gibbs Sampling Manual.Cambridge: MRC Biostatistic Unit, Institute of Public Health)and Albert & Chib (1997, J. Am. Stat. Assoc., 92, 916925).In addition, a new theoretical result regarding the joint posteriordistribution for the parameters is provided. The model proposedhas been implemented for an effectiveness study of a selectionof Lombard hospitals. 相似文献
995.
Lev?B.?Levitin Tom?ToffoliEmail author Zac?Walton 《International Journal of Theoretical Physics》2005,44(2):219-228
We consider a fixed quantum measurement performed over n identical copies of quantum states. Using a rigorous notion of distinguishability based on Shannon’s 12th theorem, we show that in the case of a single qubit, the number of distinguishable states is
, where (α1,α2) is the angle interval from which the states are chosen. In the general case of an N-dimensional Hilbert space and an area Ω of the domain on the unit sphere from which the states are chosen, the number of distinguishable states is
. The optimal distribution is uniform over the domain in Cartesian coordinates. 相似文献
996.
K.?V.?Zubowa A.?V.?Zubow V.?A.?ZubowEmail author 《Journal of Applied Spectroscopy》2005,72(6):840-847
Using the flicker-noise method (FNM), we investigated the oscillations of clusters in aqueous solutions of NaCl in the range
of concentrations from 0.1 to 26.0 mass %. It has been established that in the solutions oscillators whose masses are similar
to the masses of the models of aggregates of solvate clusters of ion pairs (SCIP) of salt with a different water content are
present. In diluted solutions (<10%), the elementary SCIP has the form NaCl· 40H2O. For the entire range of concentrations the SCIPs are given by structures based on the cubic system of the sodium chloride
system. The base structure for them is a cube formed from 12 SCIPs of salt. The largest cluster revealed by the FNM method
for all investigated concentrations of salt had a mass of ≈1.5 million D. The presence of NaCl in water leads to a collapse
of its cluster structure, except for the smallest clusters (H2O)10…11, whose concentration increases with temperature or solution concentration. The distribution of SCIPs changes dramatically
at a temperature above 300 K. The possible structures of SCIPs are given and the mechanism of their formation is discussed.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 72, No. 6, pp. 766–772, November–December, 2005. 相似文献
997.
Christopher?J.?FewsterEmail author Izumi?ojima Martin?Porrmann 《Letters in Mathematical Physics》2005,73(1):1-15
In this Letter we try to settle some confused points concerning the use of the notion of p-nuclearity in the mathematical and physical literature, pointing out that the nuclearity index in the physicists’ sense vanishes for any p> 1. Our discussion of these issues suggests a new perspective, in terms of ε-entropy and operator spaces, which might permit connections to be drawn between phase space criteria and quantum energy inequalities.Mathematics Subject Classification (2000): 81T05, 47B10, 47L25. 相似文献
998.
For two types of stochastic particle systems in we show non-explosion in finite time by proving that their respective generators are L1(μ)-unique, where μ is their respective invariant (in these cases even symmetrizing) measure. We also prove the much harder L2(μ)-uniqueness in both models. 相似文献
999.
S. A. Mikhnov 《Journal of Applied Spectroscopy》2004,71(5):757-759
It has been found that the phase shift min in the synchronous detection block that ensures the minimum amplitude of the EPR lines of ruby, diphenylpicrylhydrazyl, and MnSO4·5H2O, depends on the amplitude of the modulationH
m of a stationary magnetic field. The dependence of min on H
m is explained by the inertial nature of the recovery of the stationary states of paramagnetic centers on a change in the magnetic field strength. 相似文献
1000.
B.A Fomin T.A Udalova E.A Zhitnitskii 《Journal of Quantitative Spectroscopy & Radiative Transfer》2004,86(1):73-85
Five HITRAN's editions (since 1992) and three radically new H2O spectral databases have been tested for their usefulness in line-by-line benchmark calculations for radiation code validations. The longwave calculations for the mid-latitude summer (MLS) atmosphere with the different HITRAN's editions revealed a good convergence (maximal discrepancies since decreased to in our flux calculations with 1992-2002 and 1996-2002 HITRAN's editions, respectively). The shortwave calculations with different HITRAN's editions revealed a good agreement: discrepancies in downward fluxes absorbed by the MLS atmosphere are less than , i.e. 0.5% for the all HITRAN's editions since 1992. It has been determined that it is unreasonable to replace HITRAN by any new H2O spectral database in benchmark calculations, although they contain essentially more spectral lines than HITRAN (up to ∼10 times). Moreover, it has been found that no new database could be useful for explaining the “anomalous absorption” problem. Two latest water vapor continuum models have been tested as well. It has been found out that these models are the main source of uncertainties in the present and previous calculations: discrepancies for the MLS atmosphere reached ∼3 and in the longwave and shortwave flux calculations, respectively. 相似文献