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2004
The MILKY WAY (the Galaxy) possesses a number of different stellar components—often referred to as populations, following the pioneering work of WALTER BAADE in the 1940s. Each of these components is described by a fairly well-defined set of observed distributions of kinematics, chemical abundance and age and has a distinctive spatial ...
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The MILKY WAY (the Galaxy) possesses a number of different stellar components—often referred to as populations, following the pioneering work of WALTER BAADE in the 1940s. Each of these components is described by a fairly well-defined set of observed distributions of kinematics, chemical abundance and age and has a distinctive spatial ...
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A modified thickness extensional disk transducer
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 1988Photolithography and chemical etching were investigated as a means of patterning miniature piezoelectric devices. Using a processing procedure analogous to that utilized in the production of integrated circuitry, concentrated hydrochloric acid and a commercially available photoresist were used to fabricate a number of complex structures from soft lead ...
Robert E. Newnham, S.E. Trolier, Qi Xu
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2005
The properties of instabilities occurring in thick disks are reviewed. Their origin and mechanism is discussed and a summary of the influence of various model parameters and stabilising effects is given.
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The properties of instabilities occurring in thick disks are reviewed. Their origin and mechanism is discussed and a summary of the influence of various model parameters and stabilising effects is given.
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The Thickness of Galactic Disks
1984The local dynamical structure of disk galaxies is broadly characterized by a vertical scale height which is nearly independent of radius, the scale height being about 1/10 of the horizontal scale length (Searle and van der Kruit, 1982) and an internal population structure wherein the oldest stars have the largest random velocities (for an analysis of ...
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Dissipation of thick accretion disks
Astrophysics and Space Science, 1983A thick accretion disk which is isentropic cannot have simple laminar flow because fluid elements follow orbits which intersect the orbits of other fluid elements, leading to turbulence in astrophysical disks which have very large Reynolds numbers.
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Imaging thick accretion disks and jets surrounding black holes
Journal of Cosmology and Astroparticle PhysicsBased on the horizon-scale magnetofluid model developed in [1], we investigate the millimeter-wave images of a geometrically thick accretion disk or a funnel wall, i.e., the magnetofluid that encloses the base of the jet region, around a Kerr black hole.
Zhenyu Zhang +3 more
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Constant Thickness Rotating Disk
2012For the constant thickness disk (h = cost; dh/dr = 0), the solving differential equation (1.28) is specialized in the following form: $$ \frac{{{{d}^2}u}}{{d{{r}^2}}} + \frac{1}{r} \cdot \frac{{du}}{{dr}} - \frac{u}{{{{r}^2}}} - \left( {1 + \nu } \right) \cdot \alpha \cdot \frac{{d{\rm T} }}{{dr}} + \left( {1 - {{\nu }^2}} \right) \cdot \frac ...
Vincenzo Vullo, Francesco Vivio
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Thick-walled Cylinders and Disks
2010In this chapter, we shall consider a class of problems in which the stresses and displacements depend only on the radius r in the cylindrical coordinate system (r,θ , z). The problems are therefore axisymmetric (i.e. there is no variation with the angle θ) nor is there any variation with the distance z along the axis.
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