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The Ability of MM5 to Simulate Ice Clouds: Systematic Comparison between Simulated and Measured Fluxes and Lidar/Radar Profiles at SIRTA Atmospheric Observatory (open access)

The Ability of MM5 to Simulate Ice Clouds: Systematic Comparison between Simulated and Measured Fluxes and Lidar/Radar Profiles at SIRTA Atmospheric Observatory

Ice clouds play a major role in the radiative energy budget of the Earth-atmosphere system (Liou 1986). Their radiative effect is governed primarily by the equilibrium between their albedo and greenhouse effects. Both macrophysical and microphysical properties of ice clouds regulate this equilibrium. For quantifying the effect of these clouds onto climate and weather systems, they must be properly characterized in atmospheric models. In this paper we use remote-sensing measurements from the SIRTA ground based atmospheric observatory (Site Instrumental de Recherche par Teledetection Atmospherique, http://sirta.lmd.polytechnique.fr). Lidar and radar observations taken over 18 months are used, in order to gain statistical confidence in the model evaluation. Along this period of time, 62 days are selected for study because they contain parts of ice clouds. We use the ''model to observations'' approach by simulating lidar and radar signals from MM5 outputs. Other more classical variables such as shortwave and longwave radiative fluxes are also used. Four microphysical schemes, among which that proposed by Reisner et al. (1998) with original or modified parameterizations of particle terminal fall velocities (Zurovac-Jevtic and Zhang 2003, Heymsfield and Donner 1990), and the simplified Dudhia (1989) scheme are evaluated in this study.
Date: March 18, 2005
Creator: Chiriaco, M.; Vautard, R.; Chepfer, H.; Haeffelin, M.; Wanherdrick, Y.; Morille, Y. et al.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 106, No. 294, Ed. 1 Friday, March 18, 2005 (open access)

Altus Times (Altus, Okla.), Vol. 106, No. 294, Ed. 1 Friday, March 18, 2005

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 18, 2005
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
A BAC-based physical map of the Drosophila buzzatii genome (open access)

A BAC-based physical map of the Drosophila buzzatii genome

Large-insert genomic libraries facilitate cloning of large genomic regions, allow the construction of clone-based physical maps and provide useful resources for sequencing entire genomes. Drosophilabuzzatii is a representative species of the repleta group in the Drosophila subgenus, which is being widely used as a model in studies of genome evolution, ecological adaptation and speciation. We constructed a Bacterial Artificial Chromosome (BAC) genomic library of D. buzzatii using the shuttle vector pTARBAC2.1. The library comprises 18,353 clones with an average insert size of 152 kb and a {approx}18X expected representation of the D. buzzatii euchromatic genome. We screened the entire library with six euchromatic gene probes and estimated the actual genome representation to be {approx}23X. In addition, we fingerprinted by restriction digestion and agarose gel electrophoresis a sample of 9,555 clones, and assembled them using Finger Printed Contigs (FPC) software and manual editing into 345 contigs (mean of 26 clones per contig) and 670singletons. Finally, we anchored 181 large contigs (containing 7,788clones) to the D. buzzatii salivary gland polytene chromosomes by in situ hybridization of 427 representative clones. The BAC library and a database with all the information regarding the high coverage BAC-based physical map described in this paper are available …
Date: March 18, 2005
Creator: Gonzalez, Josefa; Nefedov, Michael; Bosdet, Ian; Casals, Ferran; Calvete, Oriol; Delprat, Alejandra et al.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 84, No. 104, Ed. 1 Friday, March 18, 2005 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 84, No. 104, Ed. 1 Friday, March 18, 2005

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: March 18, 2005
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Beam Halo Formation in High-Intensity Beams. (open access)

Beam Halo Formation in High-Intensity Beams.

Studies of beam halo became unavoidable feature of high-intensity machines where uncontrolled beam loss should be kept to extremely small level. For a well controlled stable beam such a loss is typically associated with the low density halo surrounding beam core. In order to minimize uncontrolled beam loss or improve performance of an accelerator, it is very important to understand what are the sources of halo formation in a specific machine of interest. The dominant mechanisms are, in fact, different in linear accelerators, circular machines or Energy Recovering Linacs (ERL). In this paper, we summarize basic mechanisms of halo formation in high-intensity beams and discuss their application to various types of accelerators of interest, such as linacs, rings and ERL.
Date: March 18, 2005
Creator: Fedotov, A. V.
Object Type: Article
System: The UNT Digital Library
Boerne Star & Hill Country Recorder (Boerne, Tex.), Vol. 99, No. 15, Ed. 1 Friday, March 18, 2005 (open access)

Boerne Star & Hill Country Recorder (Boerne, Tex.), Vol. 99, No. 15, Ed. 1 Friday, March 18, 2005

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: March 18, 2005
Creator: Watson, Steven G.
Object Type: Newspaper
System: The Portal to Texas History
Brady Standard-Herald and Heart O' Texas News (Brady, Tex.), Ed. 1 Friday, March 18, 2005 (open access)

Brady Standard-Herald and Heart O' Texas News (Brady, Tex.), Ed. 1 Friday, March 18, 2005

Semiweekly newspaper from Brady, Texas that includes local, state, and national news along with advertising.
Date: March 18, 2005
Creator: Stewart, James E.
Object Type: Newspaper
System: The Portal to Texas History
Central Asia:  Regional Developments and Implications for U.S. Interests (open access)

Central Asia: Regional Developments and Implications for U.S. Interests

This report provides an overview of U.S. policy concerns and relations with countries in central Asia. The report discusses issues such as Fostering Pro-Western Orientations, Obstacles to Peace and Independence, Democratization and Human Rights, Security and Arms Control, Trade and Investment, and provides an Aid Overview.
Date: March 18, 2005
Creator: Nichol, Jim
Object Type: Report
System: The UNT Digital Library
The Clifton Record (Clifton, Tex.), Vol. 110, No. 11, Ed. 1 Friday, March 18, 2005 (open access)

The Clifton Record (Clifton, Tex.), Vol. 110, No. 11, Ed. 1 Friday, March 18, 2005

Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date: March 18, 2005
Creator: Smith, W. Leon
Object Type: Newspaper
System: The Portal to Texas History
Combinatorial Algorithms for Computing Column Space Bases ThatHave Sparse Inverses (open access)

Combinatorial Algorithms for Computing Column Space Bases ThatHave Sparse Inverses

This paper presents a combinatorial study on the problem ofconstructing a sparse basis forthe null-space of a sparse, underdetermined, full rank matrix, A. Such a null-space is suitable forsolving solving many saddle point problems. Our approach is to form acolumn space basis of A that has a sparse inverse, by selecting suitablecolumns of A. This basis is then used to form a sparse null-space basisin fundamental form. We investigate three different algorithms forcomputing the column space basis: Two greedy approaches that rely onmatching, and a third employing a divide and conquer strategy implementedwith hypergraph partitioning followed by the greedy approach. We alsodiscuss the complexity of selecting a column basis when it is known thata block diagonal basis exists with a small given block size.
Date: March 18, 2005
Creator: Pinar, Ali; Chow, Edmond & Pothen, Alex
Object Type: Article
System: The UNT Digital Library
Dallas Voice (Dallas, Tex.), Vol. 21, No. 43, Ed. 1 Friday, March 18, 2005 (open access)

Dallas Voice (Dallas, Tex.), Vol. 21, No. 43, Ed. 1 Friday, March 18, 2005

Weekly newspaper from Dallas, Texas that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: March 18, 2005
Creator: Vercher, Dennis
Object Type: Newspaper
System: The UNT Digital Library
Department of Energy: Further Actions Are Needed to Strengthen Contract Management for Major Projects (open access)

Department of Energy: Further Actions Are Needed to Strengthen Contract Management for Major Projects

A letter report issued by the Government Accountability Office with an abstract that begins "The Department of Energy (DOE) pays its contractors billions of dollars each year to implement its major projects--those costing more than $400 million each. Many major projects have experienced substantial cost and schedule overruns, largely because of contract management problems. GAO was asked to assess, for major departmental projects, (1) DOE's use of performance incentives to effectively control costs and maintain schedules, (2) the reliability of the data DOE uses to monitor and assess contractor performance, and (3) the reliability of the Project Assessment and Reporting System (PARS) data that senior managers use for project oversight."
Date: March 18, 2005
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
The Dependence of Cloud Particle Size on Non-Aerosol-Loading Related Variables (open access)

The Dependence of Cloud Particle Size on Non-Aerosol-Loading Related Variables

An enhanced concentration of aerosol may increase the number of cloud drops by providing more cloud condensation nuclei (CCN), which in turn results in a higher cloud albedo at a constant cloud liquid water path. This process is often referred to as the aerosol indirect effect (AIE). Many in situ and remote sensing observations support this hypothesis (Ramanathan et al. 2001). However, satellite observed relations between aerosol concentration and cloud drop size are not always in agreement with the AIE. Based on global analysis of cloud effective radius (r{sub e}) and aerosol number concentration (N{sub a}) derived from satellite data, Sekiguchi et al. (2003) found that the correlations between the two variables can be either negative, or positive, or none, depending on the location of the clouds. They discovered that significantly negative r{sub e} - N{sub a} correlation can only be identified along coastal regions of the continents where abundant continental aerosols inflow from land, whereas Feingold et al. (2001) found that the response of r{sub e} to aerosol loading is the greatest in the region where aerosol optical depth ({tau}{sub a}) is the smallest. The reason for the discrepancy is likely due to the variations in cloud macroscopic properties …
Date: March 18, 2005
Creator: Shao, H. & Liu, G.
Object Type: Article
System: The UNT Digital Library
Development and Manufacture of Cost Effective Composite Drill Pipe (open access)

Development and Manufacture of Cost Effective Composite Drill Pipe

This technical report presents the engineering research, process development and data accomplishments that have transpired to date in support of the development of Cost Effective Composite Drill Pipe (CDP). The report presents progress made from October 1, 2003 through September 30, 2004 and contains the following discussions: (1) Direct Electrical Connection for Rotary Shoulder Tool Joints; (2) Conductors for inclusion in the pipe wall (ER/DW-CDP); (3) Qualify fibers from Zoltek; (4) Qualify resin from Bakelite; (5) First commercial order for SR-CDP from Integrated Directional Resources (SR-CDP); and (6) Preparation of papers for publication and conference presentations.
Date: March 18, 2005
Creator: Leslie, James C.; Leslie, James C., II; Truong, Lee; Heard, James T. & Manekas, Peter
Object Type: Report
System: The UNT Digital Library
The Effect of Non-Lambertian Surface Reflectance on Aerosol Radiative Forcing (open access)

The Effect of Non-Lambertian Surface Reflectance on Aerosol Radiative Forcing

Surface reflectance is an important factor in determining the strength of aerosol radiative forcing. Previous studies of radiative forcing assumed that the reflected surface radiance is isotropic and does not depend on incident illumination angle. This Lambertian reflection model is not a very good descriptor of reflectance from real land and ocean surfaces. In this study we present computational results for the seasonal average of short and long wave aerosol radiative forcing at the top of the atmosphere and at the surface. The effect of the Lambertian assumption is found through comparison with calculations using a more detailed bi-direction reflectance distribution function (BRDF).
Date: March 18, 2005
Creator: Ricchiazzi, P.; O'Hirok, W. & Gautier, C.
Object Type: Article
System: The UNT Digital Library
Evaluation of the Corrosivity of Dust Deposited on Waste Packages at Yucca Mountain, Nevada (open access)

Evaluation of the Corrosivity of Dust Deposited on Waste Packages at Yucca Mountain, Nevada

Small amounts of dust will be deposited on the surfaces of waste packages in drifts at Yucca Mountain during the operational and the preclosure ventilation periods. Salts present in the dust will deliquesce as the waste packages cool and relative humidity in the drifts increases. In this paper, we evaluate the potential for brines formed by dust deliquescence to initiate and sustain localized corrosion that results in failure of the waste package outer barrier and early failure of the waste package. These arguments have been used to show that dust deliquescence-induced localized or crevice corrosion of the waste package outer barrier (Alloy 22) is of low consequence with respect to repository performance. Measured atmospheric and underground dust compositions are the basis of thermodynamic modeling and experimental studies to evaluate the likelihood of brine formation and persistence, the volume of brines that may form, and the relative corrosivity of the initial deliquescent brines and of brines modified by processes on the waste package surface. In addition, we evaluate several mechanisms that could inhibit or stifle localized corrosion should it initiate. The dust compositions considered include both tunnel dust samples from Yucca Mountain, National Airfall Deposition Program rainout data, and collected windblown …
Date: March 18, 2005
Creator: Bryan, C.; Jarek, R.; Wolery, T.; Shields, D.; Sutton, M.; Hardin, E. et al.
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Friday, March 18, 2005 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Friday, March 18, 2005

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: March 18, 2005
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Formation of Nanopore-Arrays by Plasma-based Thin FilmDeposition (open access)

Formation of Nanopore-Arrays by Plasma-based Thin FilmDeposition

The ability to fabricate membranes with arrays of apertures only a few nanometers in diameter are important to many fields of research, including ion beam lithography, DNA sequencing, single ion implantations, and single molecule studies. Because even the state-of-the-art lithography tools are limited in their ability to produce nanoscale features, alternative methods of fabricating single pores of nanometer scale have been developed, using ion-beam sculpting and focused-ion-beam assisted deposition. However, these methods cannot simultaneously produce multiple holes of nanometer dimension. Here we report a means of forming arrays of nanopores simultaneously on a thin, solid-state membrane using plasma-based thin-film deposition. By depositing layers of metallic thin films, the aperture sizes of pores in a pre-fabricated membrane can be reduced from a couple of micrometers down to tens of nanometers and even smaller. The technique offers a way to reduce the sizes of aperture of any shape in a variety of substrate materials, both conducting and insulating. Such arrays of nanopores can serve as membrane channels for DNA sequencing, as masks in ion-beam imprinters, for the fabrication of quantum dots, and in other applications.
Date: March 18, 2005
Creator: Ji, Qing; Chen, Y.; Jiang, Ximan; Ji, Lili & Leung, K. N.
Object Type: Report
System: The UNT Digital Library
Free Trade Area of the Americas: Missed Deadline Prompts Efforts to Restart Stalled Hemispheric Trade Negotiations (open access)

Free Trade Area of the Americas: Missed Deadline Prompts Efforts to Restart Stalled Hemispheric Trade Negotiations

A letter report issued by the Government Accountability Office with an abstract that begins "If completed, the Free Trade Area of the Americas (FTAA) agreement would encompass an area of 800 million people and about $13 trillion in production of goods and services, making it the most significant regional trade initiative presently being pursued by the United States. The 34 democratic nations of the Western Hemisphere formally launched negotiations towards a FTAA in 1998, and set a January 2005 deadline for concluding a FTAA agreement. GAO was asked to analyze (1) progress made in FTAA negotiations since GAO's last (April 2003) report (2) factors that have been influencing the FTAA's progress; and (3) future prospects for the FTAA. USTR disagreed with our report, stating it was a poorly framed portrayal of progress and problems in the negotiations, overemphasized the role of the United States and Brazil in the current impasse, and did not give sufficient weight to U.S. efforts to make progress. GAO made several changes in response, but disagreed with USTR's assessment. The Departments of State, Commerce, and Agriculture provided technical comments, which we incorporated."
Date: March 18, 2005
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Grass Burr (Weatherford, Tex.), Vol. 83, No. 5, Ed. 1 Friday, March 18, 2005 (open access)

Grass Burr (Weatherford, Tex.), Vol. 83, No. 5, Ed. 1 Friday, March 18, 2005

Student newspaper of Weatherford High School in Weatherford, Texas that includes school news and information along with advertising.
Date: March 18, 2005
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Dallas, Tex.), Vol. 28, No. 325, Ed. 1 Friday, March 18, 2005 (open access)

The Greensheet (Dallas, Tex.), Vol. 28, No. 325, Ed. 1 Friday, March 18, 2005

Free weekly newspaper that includes business and classified advertising.
Date: March 18, 2005
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Dallas, Tex.), Vol. 28, No. 326, Ed. 1 Friday, March 18, 2005 (open access)

Greensheet (Dallas, Tex.), Vol. 28, No. 326, Ed. 1 Friday, March 18, 2005

Free weekly newspaper that includes business and classified advertising.
Date: March 18, 2005
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 36, No. 70, Ed. 1 Friday, March 18, 2005 (open access)

Greensheet (Houston, Tex.), Vol. 36, No. 70, Ed. 1 Friday, March 18, 2005

Free weekly newspaper that includes business and classified advertising.
Date: March 18, 2005
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 36, No. 71, Ed. 1 Friday, March 18, 2005 (open access)

Greensheet (Houston, Tex.), Vol. 36, No. 71, Ed. 1 Friday, March 18, 2005

Free weekly newspaper that includes business and classified advertising.
Date: March 18, 2005
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History