1,584 research outputs found
Nationalization, modernization and symbolic media: towards a comparative historical sociology of the nation-state
"In the formation process of the nation-state, there took place processes analogous to globalization. People and things moved on a nationwide scale and local regions and people became homogenized and also differentiated. Such process can be called 'nationalization'. By taking its meaning as a more comprehensive one than ever, we can understand the formation process of the nation-state more accurately. Also we have to differentiate 'nationalization' from 'modernization'. We regard that modernization is the process of disembedding people from various 'existences' in which they have been embedded. In the course of disembedding, people began to regard 'existences' as means and obstacles for 'actions'. That is to say, 'predominance of actions over existences' has occurred. The reason why such 'predominance of actions' has taken place can be made clear by introducing 'symbolic media' which reduce 'existences' to something on each standard. In history symbolic media have been conflicting and allying with each other. 'Predominance of actions', that is to say, modernization advanced through such conflicts and alliance." (author's abstract
Eccentricity Trap: Trapping of Resonantly Interacting Planets near the Disk Inner Edge
Using orbital integration and analytical arguments, we have found a new
mechanism (an "eccentricity trap") to halt type I migration of planets near the
inner edge of a protoplanetary disk. Because asymmetric eccentricity damping
due to disk-planet interaction on the innermost planet at the disk edge plays a
crucial role in the trap, this mechanism requires continuous eccentricity
excitation and hence works for a resonantly interacting convoy of planets. This
trap is so strong that the edge torque exerted on the innermost planet can
completely halt type I migrations of many outer planets through mutual resonant
perturbations. Consequently, the convoy stays outside the disk edge, as a
whole. We have derived semi-analytical formula for the condition for the
eccentricity trap and predict how many planets are likely to be trapped. We
found that several planets or more should be trapped by this mechanism in
protoplanetary disks that have cavities. It can be responsible for the
formation of non-resonant, multiple, close-in super-Earth systems extending
beyond 0.1AU. Such systems are being revealed by radial velocity observations
to be quite common around solar-type stars.Comment: 24 pages, 7 figures, accepted for publication in Ap
Flankside plasma sheet isolation in the ionosphere for northward interplanetary magnetic field
The Tenth Symposium on Polar Science/Ordinary sessions: [OS] Space and upper atmospheric sciences, Wed. 4 Dec. / Institute of Statistics and Mathematics (ISM) Seminar room 2 (D304) (3rd floor
Heat transfer in a dense gas between two parallel plates
Time-dependent heat transfer in a dense gas between two parallel plates, which is initiated by an abrupt change in temperature of one plate, is numerically investigated on the basis of the Enskog equation under the diffuse reflection boundary condition. Numerical computation is carried out by a finite-difference scheme combined with the Fourier spectral method for the efficient computation of the collision term of the Enskog equation. As a result, macroscopic quantities of the gas, such as heat flux and temperature, are obtained for various Knudsen numbers and ratios of the molecular diameter to the distance between plates. Compared to the case of an ideal gas, the heat flux in the stationary state is enhanced due to an effect of the finite size of molecules for not only small but also intermediate Knudsen numbers. The results imply that the finite-size effect also affects the propagation of disturbances in the initial stage, particularly for small Knudsen numbers
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