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CLOUD PARAMETERIZATIONS, CLOUD PHYSICS, AND THEIR CONNECTIONS: AN OVERVIEW. (open access)

CLOUD PARAMETERIZATIONS, CLOUD PHYSICS, AND THEIR CONNECTIONS: AN OVERVIEW.

This paper consists of three parts. The first part is concerned with the parameterization of cloud microphysics in climate models. We demonstrate the crucial importance of spectral dispersion of the cloud droplet size distribution in determining radiative properties of clouds (e.g., effective radius), and underline the necessity of specifying spectral dispersion in the parameterization of cloud microphysics. It is argued that the inclusion of spectral dispersion makes the issue of cloud parameterization essentially equivalent to that of the droplet size distribution function, bringing cloud parameterization to the forefront of cloud physics. The second part is concerned with theoretical investigations into the spectral shape of droplet size distributions in cloud physics. After briefly reviewing the mainstream theories (including entrainment and mixing theories, and stochastic theories), we discuss their deficiencies and the need for a paradigm shift from reductionist approaches to systems approaches. A systems theory that has recently been formulated by utilizing ideas from statistical physics and information theory is discussed, along with the major results derived from it. It is shown that the systems formalism not only easily explains many puzzles that have been frustrating the mainstream theories, but also reveals such new phenomena as scale-dependence of cloud droplet size …
Date: February 12, 2002
Creator: Liu, Y.; Daum, P. H.; Chai, S. K. & Liu, F.
System: The UNT Digital Library
COMPILATION OF REGIONAL TO GLOBAL INVENTORIES OF ANTHROPOGENIC EMISSIONS (open access)

COMPILATION OF REGIONAL TO GLOBAL INVENTORIES OF ANTHROPOGENIC EMISSIONS

The mathematical modeling of the transport and transformation of trace species in the atmosphere is one of the scientific tools currently used to assess atmospheric chemistry, air quality, and climatic conditions. From the scientific but also from the management perspectives accurate inventories of emissions of the trace species at the appropriate spatial, temporal, and species resolution are required. There are two general methodologies used to estimate regional to global emissions: bottom-up and top-down (also known as inverse modeling). Bottom-up methodologies to estimate industrial emissions are based on activity data, emission factors (amount of emissions per unit activity), and for some inventories additional parameters (such as sulfur content of fuels). Generally these emissions estimates must be given finer sectoral, spatial (usually gridded), temporal, and for some inventories species resolution. Temporal and spatial resolution are obtained via the use of surrogate information, such as population, land use, traffic counts, etc. which already exists in or can directly be converted to gridded form. Speciation factors have been and are being developed to speciate inventories of NO{sub x}, particulate matter, and hydrocarbons. Top-down (inverse modeling) methodologies directly invert air quality measurements in terms of poorly known but critical parameters to constrain the emissions needed …
Date: November 2002
Creator: Benkovitz, C. M.
System: The UNT Digital Library
Storage Manager and File Transfer Web Services (open access)

Storage Manager and File Transfer Web Services

Web services are emerging as an interesting mechanism for a wide range of grid services, particularly those focused upon information services and control. When coupled with efficient data transfer services, they provide a powerful mechanism for building a flexible, open, extensible data grid for science applications. In this paper we present our prototype work on a Java Storage Resource Manager (JSRM) web service and a Java Reliable File Transfer (JRFT) web service. A java client (Grid File Manager) on top of JSRM and is developed to demonstrate the capabilities of these web services. The purpose of this work is to show the extent to which SOAP based web services are an appropriate direction for building a grid-wide data management system, and eventually grid-based portals.
Date: July 2002
Creator: Watson, William A., III; Chen, Ying; Chen, Jie & Akers, Walt
System: The UNT Digital Library
RESONANT X-RAY SCATTERING AS A PROBE OF ORBITAL AND CHARGE ORDERING. (open access)

RESONANT X-RAY SCATTERING AS A PROBE OF ORBITAL AND CHARGE ORDERING.

Resonant x-ray scattering is a powerful experimental technique for probing orbital and charge ordering. It involves tuning the incident photon energy to an absorption edge of the relevant ion and observing scattering at previously ''forbidden'' Bragg peaks, and it allows high-resolution, quantitative studies of orbital and charge order--even from small samples. Further, resonant x-ray scattering from orbitally ordered systems exhibits polarization- and azimuthal-dependent properties that provide additional information about the details of the orbital order that is difficult, or impossible, to obtain with any other technique. In the manganites, the sensitivity to charge and orbital ordering is enhanced when the incident photon energy is tuned near the Mn K absorption edge (6.539 keV), which is the lowest energy at which a 1s electron can be excited into an unoccupied state. In this process, the core electron is promoted to an intermediate excited state, which decays with the emission of a photon. The sensitivity to charge ordering is believed to be due to the small difference in K absorption edges of the Mn{sup 3+} and Mn{sup 4+} sites. For orbital ordering, the sensitivity arises from a splitting--or difference in the weight of the density of states [239]--of the orbitals occupied by …
Date: May 13, 2002
Creator: Nelson, C. S.; Hill, J. P. & Gibbs, D.
System: The UNT Digital Library
Advancements in the characterization of 'hyper-thin' oxynitride gate dielectrics through exit wave reconstruction HRTEM and XPS (open access)

Advancements in the characterization of 'hyper-thin' oxynitride gate dielectrics through exit wave reconstruction HRTEM and XPS

The physical thickness of silicon oxynitride gate dielectric materials currently in development have dimensions in the range of 15-20 Angstrom ({approx}6-8 oxygen atoms), while approaching the dielectric constant equivalent oxide thickness (EOT) of 12 Angstrom silicon dioxide. These structures present serious challenges in meeting stringent requirements within the semiconductor industry for precise determination of thickness, interfacial roughness and chemical distribution. Limitations in conventional HRTEM must be removed that would minimize errors in such measurements. Our approach was to use the National Center for Electron Microscopy (NCEM) One Angstrom Microscope (O Angstrom M), together with focal series acquisition (FSA) and exit wave reconstruction (EWR) techniques to obtain <0.8A interpretable resolution. HRTEM data on the same oxynitride materials from an aberration corrected (Cs=0) microscope were also collected as part of this work, as were scanning TEM (STEM) measurements. The H RTEM characterization provides an absolute calibration and validation for a precise ''near-line'' metrology to determine gate oxide thickness and nitrogen dose using x-ray photoelectron spectroscopy (XPS).
Date: September 1, 2002
Creator: Principe, E.L.; Watson, D.G. & Kisielowski, C.
System: The UNT Digital Library
THE DYNAMICS OF HYDROGEN ATOM ABSTRACTION FROM POLYATOMIC MOLECULES. (open access)

THE DYNAMICS OF HYDROGEN ATOM ABSTRACTION FROM POLYATOMIC MOLECULES.

The hydrogen atom abstraction reaction is an important fundamental process that is extensively involved in atmospheric and combustion chemistry. The practical significance of this type of reaction with polyatomic hydrocarbons is manifest, which has led to many kinetics studies. The detailed understanding of these reactions requires corresponding dynamics studies. However, in comparison to the A + HX {radical} AH + X reactions, the study of the dynamics of A + HR {yields} AH + R reactions is much more difficult, both experimentally and theoretically (here and in the following, A stands for an atom, X stands for a halogen atom, and R stands for a polyatomic hydrocarbon radical). The complication stems from the structured R, in contrast to the structureless X. First of all, there are many internal degrees of freedom in R that can participate in the reaction. In addition, there are different carbon sites from which an H atom can be abstracted, and the dynamics are correspondingly different; there are also multiple identical carbon sites in HR and in the picture of a local reaction, there exist competitions between neighboring H atoms, and so on. Despite this complexity, there have been continuing efforts to obtain insight into the …
Date: November 21, 2002
Creator: Liu, X. & Suits, A. G.
System: The UNT Digital Library
THE RHIC ACCELERATOR. (open access)

THE RHIC ACCELERATOR.

This review discusses the design and initial operation of the Relativistic Heavy Ion Collider (RHIC), noting the novel features of a heavy ion collider that are distinct from conventional hadron colliders. These features reflect the experimental requirements of operation with a variety of ion species over a wide energy range, including collisions between ions of unequal energies and polarized protons. Other unique aspects of RHIC include intrabeam scattering, interaction-region error compensation, and transition crossing with a slow ramp rate. The RHIC facility has just completed the second physics run after beam commissioning in 2000.
Date: January 2002
Creator: Harrison, M.; Peggs, S. & Roser, T.
System: The UNT Digital Library
Small Wind Electric Systems: A U.S. Consumer's Guide (open access)

Small Wind Electric Systems: A U.S. Consumer's Guide

The U.S. Consumer's Guide for Small Wind Electric systems provides consumers with enough information to help them determine if a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include: how to make your home more energy efficient, how to choose the right size turbine, the parts of a wind electric system, determining if there is enough wind resource on your site, choosing the best site for your turbine, connecting your system to the utility grid, and if it's possible to become independent of the utility grid using wind energy.
Date: October 31, 2002
Creator: O'Dell, K.
System: The UNT Digital Library
Highlighting High Performance: National Renewable Energy Laboratory's Thermal Test Facility, Golden, Colorado. Office of Building Technology State and Community Programs (BTS) Brochure (open access)

Highlighting High Performance: National Renewable Energy Laboratory's Thermal Test Facility, Golden, Colorado. Office of Building Technology State and Community Programs (BTS) Brochure

The National Renewable Energy Laboratory's Thermal Test Facility in Golden, Colorado, was designed using a whole-building approach--looking at the way the building's systems worked together most efficiently. Researchers monitor the performance of the 11,000-square-foot building, which boasts an energy cost savings of 63% for heating, cooling, and lighting. The basic plan of the building can be adapted to many needs, including retail and warehouse space. The Thermal Test Facility contains office and laboratory space; research focuses on the development of energy-efficiency and renewable energy technologies that are cost-effective and environmentally friendly.
Date: October 21, 2002
Creator: Burgert, S.
System: The UNT Digital Library
Charreada: Mexican Rodeo in Texas (open access)

Charreada: Mexican Rodeo in Texas

Collection of photographs and essays documenting the charreada rodeo tradition and its history in Texas. Index starts on page 97.
Date: 2002
Creator: Abernethy, Francis Edward; Rendon, Al; Hambric, Julia, 1952- & Woolley, Bryan
System: The UNT Digital Library
Roadside Crosses in Contemporary Memorial Culture (open access)

Roadside Crosses in Contemporary Memorial Culture

In this study of roadside crosses, the first of its kind, Holly Everett presents the history of these unique commemoratives and their relationship to contemporary memorial culture. The meaning of these markers is presented in the words of grieving parents, high school students, public officials, and private individuals whom the author interviewed during her fieldwork in Texas.
Date: 2002
Creator: Everett, Holly J.
System: The UNT Digital Library
Abilene Philharmonic Playbill: February 23-March 9, 2002 (open access)

Abilene Philharmonic Playbill: February 23-March 9, 2002

Program for an Abilene Philharmonic concert that ran from February 23rd to March 9th during the 51st season. It includes information about the pieces performed, artists and musicians, and advertising from local companies.
Date: February 2002
Creator: Abilene Philharmonic
System: The Portal to Texas History
Abilene Philharmonic Playbill: April 6-May 4, 2002 (open access)

Abilene Philharmonic Playbill: April 6-May 4, 2002

Program for an Abilene Philharmonic concert that ran from April 6th to May 4th during the 51st season. It includes information about the pieces performed, artists and musicians, and advertising from local companies.
Date: April 2002
Creator: Abilene Philharmonic
System: The Portal to Texas History
Synchronizing estrus in cattle (open access)

Synchronizing estrus in cattle

This document provides information on synchronizing estrus in cattle.
Date: August 2002
Creator: Sprott, L. R. & Carpenter, B. B.
System: The Portal to Texas History
Public officers : traps for the unwary : conflict of interest, nepotism, dual office holding, automatic resignation, Whistleblower Act. (open access)

Public officers : traps for the unwary : conflict of interest, nepotism, dual office holding, automatic resignation, Whistleblower Act.

The Public Officers: Traps for the Unwary 2002 addresses several legal issues that you might encounter conflict of interest, nepotism, dual office holding, automatic resignation, and the Whistleblower Act. This updated handbook incorporates legislative changes, recent case law, and attorney general opinions that have been issued since the handbook was last published in 2000.
Date: 2002
Creator: Texas. Attorney-General's Office.
System: The Portal to Texas History
Men and the breastfeeding experience. (open access)

Men and the breastfeeding experience.

This documents provides a motivational and educational lesson for prospective fathers and may be presented to them with or without their pregnant partners being present. It encourages dads to support their partner's efforts to breastfeed.
Date: June 2002
Creator: Texas. Department of Health.
System: The Portal to Texas History
Texas State Office of Risk Management Strategic Plan: Fiscal Years 2003-2007 (open access)

Texas State Office of Risk Management Strategic Plan: Fiscal Years 2003-2007

Agency strategic plan for the Texas State Office of Risk Management describing the organization's planned services, activities, and other goals during fiscal years 2003 through 2007.
Date: June 17, 2002
Creator: Texas. State Office of Risk Management.
System: The Portal to Texas History
Texas State Office of Risk Management Requests for Legislative Appropriations: Fiscal Years 2004 and 2005 (open access)

Texas State Office of Risk Management Requests for Legislative Appropriations: Fiscal Years 2004 and 2005

A legislative appropriation request for the biennium 2004-2005, in order to provide more effective claims administration and risk management services and ultimately result in savings to state agencies in the form of reduced workers' compensation claims and costs, reduced insurance purchases and improved insurance coverages, and more effective risk management programs.
Date: September 18, 2002
Creator: Texas. State Office of Risk Management.
System: The Portal to Texas History
Texas Lottery Commission Strategic Plan: Fiscal Years 2003-2007 (open access)

Texas Lottery Commission Strategic Plan: Fiscal Years 2003-2007

Agency strategic plan for the Texas Lottery Commission describing the organization's planned services, activities, and other goals during fiscal years 2003 through 2007.
Date: June 17, 2002
Creator: Texas Lottery Commission
System: The Portal to Texas History
Managing Insect and Mite Pests of Texas Corn (open access)

Managing Insect and Mite Pests of Texas Corn

This guide discusses insect and mite pests in the approximate seasonal order that they damage corn- pre-emergence, seedling to tassel and tassel to hard dough.
Date: February 2002
Creator: Porter, Patrick; Cronholm, Gregory B.; Troxclair, Noel; Patrick, Carl D.; Morrison, Pat & Archer, Thomas L.
System: The Portal to Texas History
Managing Texas Groundwater Resources : Through Groundwater Conservation Districts (open access)

Managing Texas Groundwater Resources : Through Groundwater Conservation Districts

"This publication provides an overview of Texas water law, a summary of the powers and responsibilities of groundwater conservation districts, a review of the processes involved in creating district, and an overview of issues related to groundwater conservation districts" (p. 1).
Date: February 2002
Creator: Texas Cooperative Extension
System: The Portal to Texas History
Total Organic Carbon (TOC) Guidance Manual (open access)

Total Organic Carbon (TOC) Guidance Manual

Document providing information on total organic carbon regulations in Texas.
Date: 2002
Creator: Texas Commission on Environmental Quality. Water Supply Division.
System: The Portal to Texas History
2002 Emissions Inventory Guidelines (open access)

2002 Emissions Inventory Guidelines

This document provides information on the importance of emissions inventory.
Date: 2002
Creator: Texas Commission on Environmental Quality. Technical Analysis Division.
System: The Portal to Texas History
[Woman's Wednesday Club Minutes, 2002-2004] (open access)

[Woman's Wednesday Club Minutes, 2002-2004]

Minutes from meetings of the Woman's Wednesday Club of Fort Worth, Texas, containing club business, motions, and events.
Date: 2002-10-02/2004-03-03
Creator: Woman's Wednesday Club
System: The Portal to Texas History