487 research outputs found
Multiple embryos, multiple nepionts and multiple equatorial layers in Cycloclypeus carpenteri.
Palaeonummulites venosus: Natural growth rates and quantification by means of CT investigation.
Evaluating the quality of a long term cultivation experiment of Operculina complanata by comparison with the natural labora\uadtory approach.
Operculina from the northwestern Pacific (Sesoko Island, Japan) Species Differentiation, Population Dynamics, Growth and Development.
Saturation of single toroidal number Alfvén modes
The results of numerical simulations are presented to illustrate the saturation mechanism of a single toroidal number Alfven mode, driven unstable, in a tokamak plasma, by the resonant interaction with energetic ions. The effects of equilibrium geometry non-uniformities and finite mode radial width on the wave-particle nonlinear dynamics are discussed. Saturation occurs as the fast-ion density flattening produced by the radial flux associated to the resonant particles captured in the potential well of the Alfven wave extends over the whole region where mode-particle power exchange can take place. The occurrence of two different saturation regimes is shown. In the first regime, dubbed resonance detuning, that region is limited by the resonance radial width (that is, the width of the region where the fast-ion resonance frequency matches the mode frequency). In the second regime, called radial decoupling, the power exchange region is limited by the mode radial width. In the former regime, the mode saturation amplitude scales quadratically with the growth rate; in the latter, it scales linearly. The occurrence of one or the other regime can be predicted on the basis of linear dynamics: in particular, the radial profile of the fast-ion resonance frequency and the mode structure. Here, we discuss how such properties can depend on the considered toroidal number and compare simulation results with the predictions obtained from a simplified nonlinear pendulum model
Late Miocene fossils from shallow marine sediments in Brunei Darussalam: systematics, palaeoenvironment and ecology
An extended hybrid magnetohydrodynamics gyrokinetic model for numerical simulation of shear Alfv\'en waves in burning plasmas
Adopting the theoretical framework for the generalized fishbonelike
dispersion relation, an extended hybrid magnetohydrodynamics gyrokinetic
simulation model has been derived analytically by taking into account both
thermal ion compressibility and diamagnetic effects in addition to energetic
particle kinetic behaviors. The extended model has been used for implementing
an eXtended version of Hybrid Magnetohydrodynamics Gyrokinetic Code (XHMGC) to
study thermal ion kinetic effects on Alfv\'enic modes driven by energetic
particles, such as kinetic beta induced Alfv\'en eigenmodes in tokamak fusion
plasmas
Determination of longevities, chamber building rates and growth functions for Operculina complanata from long term cultivation experiments
Heterostegina depressa growth model: what does cell volume tell us about biogeography and ecology?
Modern Foraminifera from a depth transect offshore Brunei Darussalam: diversity, sedimentation rate and preservation pathways.
- …