Context. Sequential supernova explosions create supershells which can break out a stratified medium producing bipolar outflows. The gas of the supershells can fragment into clouds which eventually fall toward the disk producing the so called galactic fountains. Aims. The aim of this paper is to calculate the expansion law and chemical enrichment of a supershell powered by the energetic feedback...

We examine the possibility of the active galactic nucleus (AGN) obscuration by dusty gas clouds that spurt out from circumnuclear starburst regions. For the purpose, the dynamical evolution of gas clouds is pursued, including the effects of radiation forces by an AGN as well as a starburst. Here, we solve the radiative transfer equations for clouds, taking into consideration the growth of cloud...

Clouds and hazes are important throughout our solar system and in the atmospheres of brown dwarfs and extrasolar giant planets. Among the brown dwarfs, clouds control the colors and spectra of the L-dwarfs; the disappearance of clouds helps herald the arrival of the T-dwarfs. The structure and composition of clouds will be among the first remote-sensing results from the direct detection of extr...

We present slitless spectra of the Narrow Line Region (NLR) in NGC 4151 from the Space Telescope Imaging Spectrograph (STIS) on HST, and investigate the kinematics and physical conditions of the emission line clouds in this region. Using medium resolution (∼ 0.5 Å) slitless spectra at two roll angles and narrow band undispersed images, we have mapped the NLR velocity field from 1.2 kpc to withi...

Forecast systems provide decision support for end-users ranging from the solar energy industry to municipalities concerned with road safety. Pavement temperature is an important variable when considering vehicle response to various weather conditions. A complex, yet direct relationship exists between tire and pavement temperatures. Literature has shown that as tire temperature increases, fricti...

Some nouns can be counted—we term these countable; other nouns cannot—we term these uncountable. By and large this distinction makes sense in terms of how we humans view the real world. Thus, for example, horses are countable, while flour is obviously not. Such cases are generally not a problem. However, there are entities that are, from a human perspective, on the borderline, which do cause pr...

In this paper, we present a physics motivated modeling method for volcanic clouds as a two fluids model. Some previous methods model smoke or clouds as one fluid, but the volcanic clouds can not be treated as one fluid. The volcanic clouds consist of the pyroclasts, the volcanic gas and the entrained air. Since the pyroclasts and the volcanic gas can be treated as one fluid, called magma, the v...

This paper proposes an image-based modeling of clouds where realistic clouds are created from satellite images using metaballs. The intention of the paper is for applications to space flight simulators, the visualization of the weather information, and the simulation of surveys of the earth. In the proposed method, the density distribution inside the clouds is defined by a set of metaballs. Par...

Recently, simulation of natural phenomena, such as water, smokes, fire, clouds, have been attempted in computer graphics. Clouds play an important role when generating images of outdoor scenes, the earth viewed from outer space and the visualization of weather information. This paper describes the modeling methods of clouds, and an efficient calculation method for light scattering due to clouds...