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H. Fawcett S. Barlag H. Becker E. Belau T. Böhringer M. Bosman V. Castillo V. Chabaud D. Bucholz C. Damerell C. Daum G. De Rijk H. Dietl S. Gill A. Gillman R. Gilmore T. Gooch P. Gras Z. Hajduk E. Higon B. Hyams D. Kelsey J. Kemmer R. Klanner U. Kötz S. Kwan B. Lücking G. Lütjens G. Lutz J. Malos W. Männer E. Neugebauer H. Palka M. Pepé G. Polok J. Richardson M. Rozanska K. Rybicki H. Seebrunner U. Stierlin R. Tapper H. Tiecke M. Turala G. Waltermann S. Watts P. Weilhammer F. Wickens L. Wiggers A. Wylie T. Zeludziewicz ACCMOR Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,46(4):513-519
The production of the neutralK ? (892) resonances by 200 GeVK ? andπ ? has been studied over the kinematic range 0.0<x f<1.0 andp t 2 <5.0 GeV2. Longitudinal and transverse momentum distributions are presented. In addition the decay angular distributions inK ? fragmentation to \(\bar K^{0*} \) have been investigated. 相似文献
84.
A trajectory-following method for unconstrained optimization 总被引:2,自引:0,他引:2
A trajectory-following method with interesting properties is considered for solving unconstrained nonlinear programming problems. The trajectory is defined by a special system of ordinary differential equations. This system uses only the gradient of the objective function. Numerical examples are given.The work of the second author was supported by the DFG Schwerpunkt Anwendungs-bezogene Optimierung and Steuerung. 相似文献
85.
The spin content of the proton is investigated by studying the flavor singlet axial structure of the nucleon in a non-topological chiral soliton model. In order to construct a nucleon state we used the generator coordinate projection method as well as a coherent state for the meson wave function. Using a standard set of parameters we found the value g A 0 ? 0.44 for the flavor singlet axial vector coupling constant. This result is not far from that of a typical valence quark model. 相似文献
86.
The time evolution of the particle number density and spectrum of massive scalar particles, coupled conformally to a classical Friedman-Robertson-Walker gravitational field is followed numerically. Not only for a pure radiation cosmos, but also for one with an inflationary interlude, the density of particles produced remains constant in time. This results in a constant equivalent temperature scale up to the Compton time of the massive particles, and opens the possibility that during a sufficiently long inflation the energy density of the particles produced can exceed that of the radiation background. 相似文献
87.
Summary Motivated by different mean value properties, the functional equationsf(x) – f(y)/x–y=[(x, y)], (i)xf(y) – yf(x)/x–y=[(x, y)] (ii) (x y) are completely solved when, are arithmetic, geometric or harmonic means andx, y elements of proper real intervals. In view of a duality between (i) and (ii), three of the results are consequences of other three.The equation (ii) is also solved when is a (strictly monotonic) quasiarithmetic mean while the real interval contains 0 and when is the arithmetic mean while the domain is a field of characteristic different from 2 and 3. (A result similar to the latter has been proved previously for (i).) 相似文献
88.
A recently derived model for stationary flow of energy and charge carriers in semiconductors—consisting of a coupled system of nonlinear elliptic equations—is analysed by the methods of singular perturbation theory. This analysis reveals the solution structure and justifies a modified version of the standard drift-diffusion approximation for charge carrier flow.
The work of the second author was supported by Österreichischer Fonds zur Förderung der wissenschaftlichen Forschung. 相似文献
Zusammenfassung Ein kürzlich hergeleitetes Modell für stationären Energie- und Ladungsträgerfluß in Halbleitern—bestehend aus einem gekoppelten System von nichtlinearen elliptischen Gleichungen—wird mit Methoden der singulären Störungstheorie analysiert. Daraus ergeben sich Aussagen über die Lösungsstruktur und eine Rechtfertigung einer modifizierten Version der klassischen Konvektions-Diffusions-Approximation für den Ladungsträgerfluß.
The work of the second author was supported by Österreichischer Fonds zur Förderung der wissenschaftlichen Forschung. 相似文献
89.
L. Havela P. Kratochvíl P. Lukáč B. Smola A. Svobodová 《Czechoslovak Journal of Physics》1988,38(4):384-387
The softening processes during and after the hot deformation (850–1180 C) in AISI 321 stainless steel were studied with respect to true strains
D and true strain rates
. The analysis of deformation curves indicates the occurrence of dynamic recrystallization for values of Zener-Hollomon parameterZ1015 s–1. The retardation of static recrystallization by fine Ti(N, C) precipitates is documented by microstructure studies and by variations of annealing conditions. 相似文献
90.