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101.
A portable bifurcation and stability analysis package, called BISTAB, is described. The package is written in FORTRAN V and can follow the connected set of equilibrium curves for a system of nonlinear ordinary differential equations in the state × parameter space by varying a bifurcation parameter. The curves are traced from an initial point with the continuation method of Kubicek, and the tangent method of Keller is used to find initial points on bifurcating curves near simple bifurcation points. Linearized stability analysis, location of Hopf bifurcation points, and sorting of points for plotting are also supported. While the package contains no new numerical methods, the lack of a requirement for any derivative information higher than the Jacobian makes BISTAB computationally efficient and useful for applied problems where nonnumerical bifurcation analysis may be difficult. 相似文献
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S. Raman P.H. Stelson G.G. Slaughter J.A. Harvey T.A. Walkiewicz G.J. Lutz L.G. Multhauf K.G. Tirsell 《Nuclear Physics A》1973,206(2):343-352
We have carried out measurements on the decay of 119In isomers and the 118Sn(n, γ) reaction to supplement Coulomb excitation measurements on 119Sn. In addition to the 311.39 keV isomeric transition in 119In, we observed 13 γ-rays in 119Sn from the decay of the 2 min and 18 min 119In isomers. These γ-rays have been incorporated into a level scheme of 119Sn with levels at 0, 23.867, 89.54, 787.01, 920.5, 921.4, 1089.5, 1187.76, 1249.67, 1304.44 and 1354 keV. Conclusive evidence for the existence of a 920.5–921.4 keV, level doublet was obtained from capture γ-ray measurements of resonance energy neutrons. 相似文献
105.
Mathematische Zeitschrift - 相似文献
106.
A mathematical model for the EEG is presented here based on physical and anatomical characteristics of the brain. The important finding is that the system is characterised by a diffusion equation whose general solution represents a Fourier series expansion for the EEG at any point of the zone under consideration. 相似文献
107.
The decay of 48K has been studied for the first time. This activity was produced by means of the 48Ca(n,p) reaction with 14 MeV neutrons. A group of five levels in 48Ca near 7 MeV accounts for ∽ 75% of the 48K β-decay strength. 相似文献
108.
W.K. Dagenhart P.H. Stelson F.K. Mcgowan R.L. Robinson W.T. Milner S. Raman W.K. Tuttle 《Nuclear Physics A》1977,284(3):484-500
Coulomb excitation of the nucleus 115Sn was studied with beams of 4He and 16O. Level energies, spins, mean-lives and B(E2) and B(M1) transition probabilities were obtained. Spin + states were observed at 497.35 and 1280.08 keV and spin + states were observed at 986.54 and 1416.78 keV. A state of 612.79 keV was observed to be indirectly excited by decay of the Coulomb excited states. Eleven B(E2) values and nine B(M1) values were obtained for the transitions between the low-lying states. In contrast to previous particle transfer results which suggested a clear distinction between shell-model and collective + and + states, our results suggest the collective strength is shared by the two + and two + states. 相似文献
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