We present an exact expression for the upscaled dynamic dispersion coefficient (D) for one-dimensional transport by Hagen-Poiseuille flow which is the basis for modeling transport in porous media idealized as capillary tubes. The theoretical model is validated by comparing the breakthrough curves (BTCs) from a 1D advection-dispersion model with dynamic D to that from direct numerical solutions ...

Air pollution has a direct impact to human health, and data-driven air quality models are useful for evaluating population exposure to air pollutants. In this paper, we propose a novel region-based Gaussian process model for estimating urban air pollution dispersion, and applied it to a large dataset of ultrafine particle (UFP) measurements collected from a network of sensors located on several...

1. General Modeling Methods 1.1. Pollutant Transport 1.2. Modeling Recommendations 2. Optimization 2.1. The Effect Function 2.2. The Objective Function 2.2.1. The Gradient of the Objective Function 2.3. Constraints 2.4. Algorithmic Considerations 3. Three Important Transport Modes 3.1. Advection and Convection 3.2. Diffusion 3.3. Dispersion 3.4. Combinations 3.4.1. Numerical Considerations 4. C...

Supercritical Fluid Extraction have been used widely in the natural material industries ,because it produced excellent mass transfer properties, ease solubility control due to temperature and pressure. A mathematical model based on shrinking-core model of the extraction process and simulation were used. Previous worker’s have used a model including axial dispersion. They give the effect of an i...

We extend the concept of the ridgeline from Ray and Lindsay (2005) to finite mixtures of general elliptical densities with possibly distinct density generators in each component. This can be used to obtain bounds for the number of modes of two-component mixtures of t distributions in any dimension. In case of proportional dispersion matrices, these have at most three modes, while for equal degr...

The Advanced Identity Representation (AIR) Project is a new interdisciplinary approach to the problem of designing identity technologies to enable imaginative selfrepresentations for users by implementing dynamic social identity models grounded in computing and cognitive science. AIR Project research develops models of social computational identity (e.g., characters, avatars, and social network...

Our multiscale air quality modeling activities are reviewed. Two different techniques, static grid nesting and dynamic grid adaptions are discussed. The mass conservation and transportive properties of our grid nesting technique are shown in a linear advection problem. Results from an air quality application to the northeastern U.S. are also presented. The solution accuracy with the adaptive gr...

OCTOBER 2004 AMERICAN METEOROLOGICAL SOCIETY | he data supporting aerosol research can be obtained either observationally or indirectly from models. Observations can be broadly divided into routine monitoring efforts, which may be used to continuously evaluate an assimilation model, or episodically generated data, localized in space and/or time (Fig. 1). Assimilated monitoring results, if they ...

In the case of a major pollution incident, terrorist attack, or a radioactive event such as the Chernobyl disaster in 1986, dispersion models are used to predict the transport of pollution away from its source, so allowing potentially affected areas to be warned or even evacuated. Thus it is important for both economic and human health reasons that there is continued research in developing and ...