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91.
J. -E. Augustin G. Cosme F. Couchot B. Dudelzak F. Fulda B. Grelaud G. Grosdidier B. Jean-Marie S. Jullian D. Lalanne V. Lepeltier B. Louis F. Mané C. Paulot R. Riskalla Ph. Roy F. Rumpf G. Szklarz Z. Ajaltouni A. Falvard J. Jousset B. Michel J. C. Montret R. Baldini S. Calcaterra G. Capon D. Bisello G. Busetto S. Limentani M. Nigro L. Pescara M. Posocco P. Sartori L. Stanco DM Collaboration 《Zeitschrift fur Physik C Particles and Fields》1987,36(3):369-376
The radiative decayJ/ψ → γ π+ π? has been studied using the 8.6 millionJ/ψ produced in the DM2 experiment at the DCIe +e? storage rings at Orsay. The π+ π? mass spectrum shows a cleanf 2 (1270) signal, and the possible presence of two other states at thef 2 (1720) andf 4 (2030) masses. For thef 2 (1270), the branching ratio BR(J/ψ →γf)xBR(f→π+ π?) is measured to be (7.50±0.30±1.12)×10?4, and the spin analysis prefers theJ=2 assignment, with helicity parametersx=0.83±0.06 andy=0.01±0.06. The existence of higher mass states is discussed. 相似文献
92.
In this paper it is shown that under certain general conditions, if the amalgamation class of a lattice variety contains
a member which does not have a 2-congruence, then the amalgamation class is not closed under ultrapowers or direct products.
In particular, the amalgamation class is not first order axiomatizable.
Received October 1, 1997; accepted in final form Feburary 26 1999. 相似文献
93.
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96.
Two-, three-, and four-interval forced-choice staircase procedures: estimator bias and efficiency 总被引:1,自引:0,他引:1
Threshold estimates for multiple-interval forced-choice staircase procedures were studied using computer simulations. A sigmoidal psychometric function shape governed the hypothetical subject's responses in the simulations. Parameters varied included the number of trials, the step size for stimulus level change, and decision rules that targeted 70.7% and 79.4% correct performance. Each threshold estimate was calculated by averaging the stimulus levels at which a reversal a stimulus level direction occurred. The results of the simulations suggest that, as the number of alternatives is increased from 2 to 4, the variability of repeated threshold estimates decreases or remains constant, and the accuracy of the estimator, in most cases, improves. A subset of the simulations was compared with data obtained in a detection-in-noise task. The behavioral data were consistent with the simulation results. Two major conclusions were reached. First, 3- and 4-interval forced-choice (IFC) procedures are more efficient than a 2IFC procedure with a decision rule that targets 70.7% correct performance even when the additional time required to complete 3- and 4IFC trials is considered. Second, the accuracy of 2IFC procedures can be improved by fitting the trial history of a staircase run using probit analysis. 相似文献
97.
98.
G. Klein Gertrud Pollauf Marie Krisch Elisabeth Farkass F. Schusta Anneliese Niethammer G. D. Lander C. K. Glycart M. Wagenaar F. Pavelka L. van Itallie A. J. Steenhauer A. L. W. E. van der Veen G. Denigès L. Rosenthaler D. Krüger E. Tschirch H. Tangl R. Fischer F. Stauder F. Dangl L. Kofler H. Hilbck C. Griebel F. Weiß A. Hinrichs L. Klemm O. Mohr H. Alber M. Gläser Th. Morawski und J. A. Rose 《Fresenius' Journal of Analytical Chemistry》1933,91(1-2):48-68
Ohne Zusammenfassung 相似文献
99.
H. Rose 《Fresenius' Journal of Analytical Chemistry》1863,2(1):1-4
Ohne ZusammenfassungVom Verfasser mitgetheilt 相似文献
100.
A new system of multivariate distributions with fixed marginal distributions is introduced via the consideration of random variates that are randomly chosen pairs of order statistics of the marginal distributions. The distributions allow arbitrary positive or negative Pearson correlations between pairs of random variates and generalise the Farlie–Gumbel–Morgenstern distribution. It is shown that the copulas of these distributions are special cases of the Bernstein copula. Generation of random numbers from the distributions is described, and formulas for the Kendall and grade (Spearman) correlations are given. Procedures for data fitting are described and illustrated with examples. 相似文献