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Immigration Benefits: Eighth Report Required by the Haitian Refugee Immigration Fairness Act of 1998 (open access)

Immigration Benefits: Eighth Report Required by the Haitian Refugee Immigration Fairness Act of 1998

Correspondence issued by the General Accounting Office with an abstract that begins "The Haitian Refugee Immigration Fairness Act (HRIFA) of 1998 authorized certain Haitian nationals and their dependents to apply to adjust their status to legal permanent residence. Section 902(k) of the act requires the Comptroller General to report every six months on the number of Haitian nationals who have applied and been approved to adjust their status to legal permanent residence. The reports are to contain a breakdown of the numbers who applied and the number who were approved as asylum applicants, parolees, children without parents, orphaned children, or abandoned children; or as the eligible dependents of these applicants, including spouses, children, and unmarried sons or daughters. As of September 30, 2002, the Immigration and Naturalization Service had received a total of 36,774 HRIFA applications and had approved 8,410 of these applications. The Executive Office for Immigration Review had 339 applications filed and had approved 117 of them."
Date: October 22, 2002
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Federal Energy Management: Agencies Are Acquiring Alternative Fuel Vehicles but Face Challenges in Meeting Other Fleet Objectives (open access)

Federal Energy Management: Agencies Are Acquiring Alternative Fuel Vehicles but Face Challenges in Meeting Other Fleet Objectives

Correspondence issued by the Government Accountability Office with an abstract that begins "Congress and the administration set forth energy objectives for federal fleets with 20 or more vehicles. Agencies are to (1) acquire alternative fuel vehicles (AFV) as 75 percent of all new light-duty vehicle acquisitions; (2) use only alternative fuel in AFVs, unless granted a waiver; (3) increase overall alternative fuel use by 10 percent annually; (4) reduce petroleum consumption by 2 percent annually through 2015; and (5) purchase plug-in hybrid electric vehicles when available and at a reasonable cost. The first two objectives are requirements in the Energy Policy Acts (EPAct) of 1992 and 2005. The last three are goals set by Executive Order 13423. GAO was asked to determine agencies' compliance with these objectives for fiscal year 2007 and how agencies are poised to meet them in the future. GAO obtained and analyzed information from the Department of Energy's (DOE) automotive database and other sources and interviewed agency officials."
Date: October 22, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
VA National Initiatives and Local Programs that Address Education and Support for Families of Returning Veterans (open access)

VA National Initiatives and Local Programs that Address Education and Support for Families of Returning Veterans

Correspondence issued by the Government Accountability Office with an abstract that begins "As the military operations in Afghanistan and Iraq--known as Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF), respectively--have progressed, increasing numbers of OEF/OIF servicemembers have transitioned to veteran status and have begun receiving care from the Department of Veterans Affairs (VA). VA data show that as of March 2008, over 868,000 OEF/OIF servicemembers, including National Guard and Reserve members, had left active duty and become eligible for VA health care, and over 340,000-- about 40 percent--had accessed VA health care services. Returning OEF/OIF veterans may have a range of health care needs, such as treatment for mental health conditions like posttraumatic stress disorder (PTSD), treatment for traumatic brain injury (TBI) or other injuries, or counseling to address difficulties readjusting from wartime military service to civilian life. Family members can play an important role in helping and supporting OEF/OIF veterans. For example, family members may notice symptoms the veteran has, such as anxiety or difficulty sleeping, and encourage the veteran to seek care. They may also help the veteran identify health care services and ensure that the veteran receives needed services. Family members may also provide emotional support--such …
Date: October 22, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
U.S. Department of Agriculture: Recommendations and Options to Address Management Deficiencies in the Office of the Assistant Secretary for Civil Rights (open access)

U.S. Department of Agriculture: Recommendations and Options to Address Management Deficiencies in the Office of the Assistant Secretary for Civil Rights

A letter report issued by the Government Accountability Office with an abstract that begins "For decades, numerous federal reports have described serious weaknesses in USDA's civil rights programs--in particular, in resolving discrimination complaints and providing minority farmers with access to programs. In 2002, Congress authorized the position of Assistant Secretary for Civil Rights (ASCR) at USDA to provide leadership for resolving these long-standing problems. GAO was asked to assess USDA's efforts to (1) resolve discrimination complaints, (2) report on minority participation in farm programs, and (3) strategically plan its efforts. GAO also reviewed experiences of other federal agencies to develop options for addressing the issues. This report is based on new and prior work, including analysis of ASCR's discrimination complaint management, strategic planning, and interviews with officials of USDA and other agencies, as well as 20 USDA stakeholder groups."
Date: October 22, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Immigration Benefits: Sixth Report Required by the Haitian Immigration Fairness Act of 1998 (open access)

Immigration Benefits: Sixth Report Required by the Haitian Immigration Fairness Act of 1998

Correspondence issued by the General Accounting Office with an abstract that begins "The Haitian Refugee Immigration Fairness Act of 1998 allows Haitian nationals and their dependents to apply to adjust their status to legal permanent residence. The act requires the Comptroller General to report every six months on the number of Haitian nationals who have applied and been approved for legal permanent residence status. GAO found that, as of September 30, 2001, the Immigration and Naturalization Service had received 35,946 applications and had approved 5,072 of them. The Executive Office for Immigration Review had 107 applications filed and had approved 87 of them."
Date: October 22, 2001
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Indian Health Service: Updated Policies and Procedures and Increased Oversight Needed for Billings and Collections from Private Insurers (open access)

Indian Health Service: Updated Policies and Procedures and Increased Oversight Needed for Billings and Collections from Private Insurers

Correspondence issued by the Government Accountability Office with an abstract that begins "The Indian Health Service (IHS), an agency in the Department of Health and Human Services (HHS), provides health care services to American Indians and Alaskan Natives. For fiscal year 2009, Congress appropriated approximately $3.6 billion for health care services to be made available through IHS. The agency provides direct medical care, including primary care services, ancillary services, and some specialty services, through its network of facilities, including hospitals, health centers, and clinics. IHS also provides funding to direct care facilities that are operated by tribes. IHS headquarters oversees 12 area offices that cover 161 service units in 35 states. The Indian Health Care Improvement Act of 1976, as amended, authorizes IHS to collect reimbursement for services provided at IHS facilities from third-party insurers, including Medicare, the federal health insurance program for elderly and disabled individuals; Medicaid, a joint federal and state health financing program for certain low-income families and individuals; and private health insurers. IHS is allowed to retain funds collected from these insurers without a corresponding offset against its appropriations, so that all revenue collected by a facility remains with that facility, supplementing its appropriations. For fiscal …
Date: October 22, 2009
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Allocation and Related Issues for Post-2012 Phases of the EU ETS (open access)

Allocation and Related Issues for Post-2012 Phases of the EU ETS

This report provides information on major design options related to the allocation of emissions allowances under the European Union Emissions Trading Scheme (the EU ETS, or "the Scheme"). The report was developed to assist the European Commission in the context of the review of options for the EU ETS after 2012, during the third and subsequent phases of the Scheme. The report covers topics related to allocation alternatives as well as several other issues. All of the material contained here was developed initially as a set of briefing notes for the Commission in 2007. The topics covered in the report are divided into two major categories: (1) assessment criteria and other general features, including cap-setting; and (2) allocation alternatives and issues specifically related to allocation.
Date: October 22, 2007
Creator: Harrison, David, Jr.; Radov, Daniel & Klevnas, Per
Object Type: Text
System: The UNT Digital Library
Combating Terrorism: Actions Needed to Improve Force Protection for DOD Deployments through Domestic Seaports (open access)

Combating Terrorism: Actions Needed to Improve Force Protection for DOD Deployments through Domestic Seaports

A letter report issued by the General Accounting Office with an abstract that begins "The October 12, 2000, attack against the Navy destroyer U.S.S. Cole in the port of Aden illustrated the danger of unconventional threats to U.S. ships in seaports. The September 11, 2001, attacks further heightened the need for a significant change in conventional antiterrorist thinking, particularly regarding threats to the U.S. homeland. The new security paradigm assumes that all U.S. forces, be they abroad or at home, are vulnerable to attack, and that even those infrastructures traditionally considered of little interest to terrorists, such as commercial seaports in the continental United States, are now commonly recognized as highly vulnerable to potential terrorist attack. Of the more than 300 seaports in the United States, the Departments of Defense (DOD) and Transportation have designated 17 as "strategic," because in the event of a large-scale military deployment, DOD would need to transport more than 95 percent of all equipment and supplies needed for military operations by sea. If the strategic ports were attacked, not only could massive civilian casualties be sustained, but DOD could also lose precious cargo and time and be forced to rely heavily on its overburdened airlift …
Date: October 22, 2002
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
Climate Change Adaptation: Strategic Federal Planning Could Help Officials Make More Informed Decisions (open access)

Climate Change Adaptation: Strategic Federal Planning Could Help Officials Make More Informed Decisions

Testimony issued by the Government Accountability Office with an abstract that begins "This testimony discusses our report to this committee on climate change adaptation and the role strategic federal planning could play in government decision making. Changes in the climate attributable to increased concentrations of greenhouse gases may have significant impacts in the United States and internationally. For example, climate change could threaten coastal areas with rising sea levels. In recent years, climate change adaptation--adjustments to natural or human systems in response to actual or expected climate change--has begun to receive more attention because the greenhouse gases already in the atmosphere are expected to continue altering the climate system into the future, regardless of efforts to control emissions. According to a recent report by the National Research Council (NRC), however, individuals and institutions whose futures will be affected by climate change are unprepared both conceptually and practically for meeting the challenges and opportunities it presents. In this context, adapting to climate change requires making policy and management decisions that cut across traditional economic sectors, jurisdictional boundaries, and levels of government. This testimony is based on our October 2009 report, which is being publicly released today, and addresses three issues: (1) …
Date: October 22, 2009
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Invasive Species: Clearer Focus and Greater Commitment Needed to Effectively Manage the Problem (open access)

Invasive Species: Clearer Focus and Greater Commitment Needed to Effectively Manage the Problem

A letter report issued by the General Accounting Office with an abstract that begins "Harmful invasive species--nonnative plants and animals that are spreading throughout the United States--have caused billions of dollars in damage to natural areas, businesses, and consumers. In 2001, the federal government issued a National Invasive Species Management Plan to focus attention on invasive species and coordinate a national control effort involving the 20 or so federal agencies that are responsible for managing them. This report discusses the economic impacts of invasive species, implementation of the management plan, and coordination of U.S. and Canadian efforts to control invasive species, including those introduced to the Great Lakes via the ballast water of ships."
Date: October 22, 2002
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
First-Time Homebuyer Tax Credit: Taxpayers' Use of the Credit and Implementation and Compliance Challenges (open access)

First-Time Homebuyer Tax Credit: Taxpayers' Use of the Credit and Implementation and Compliance Challenges

Testimony issued by the Government Accountability Office with an abstract that begins "This testimony discusses taxpayers' use of the First-time Homebuyer Credit (FTHBC) and the Internal Revenue Service's (IRS) implementation and compliance challenges. As an important part of the recent economic stimulus efforts, Congress enacted the FTHBC to assist the struggling real estate market and encourage taxpayers to purchase their first home. The credit initially was enacted by the Housing and Economic Recovery Act of 2008 (Housing Act) and revised by the American Recovery and Reinvestment Act of 2009 (Recovery Act). The 2008 FTHBC provided taxpayers a credit of up to $7,500 that must be paid back over 15 years. The Recovery Act increased the maximum credit for the 2009 FTHBC to $8,000, with no payback required unless the home ceases to be the taxpayer's principal residence within 3 years. This $8,000 credit is a refundable tax credit that is paid out even if there is no tax liability or the credit exceeds the amount of any tax due. The 2009 FTHBC was enacted into law on February 17, 2009, but eligibility was made retroactive for homes purchased beginning January 1, 2009. This testimony today, based on on-going work, describes …
Date: October 22, 2009
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Financial Management: Audit of the Centennial of Flight Commission (open access)

Financial Management: Audit of the Centennial of Flight Commission

Correspondence issued by the General Accounting Office with an abstract that begins "The Centennial of Flight Commission was created in 1998 to provide recommendations and advice to the President, Congress, and federal agencies on ways to encourage and promote national and international participation and sponsorships in commemoration of the centennial of powered flight. All 45 of the Commission's recorded financial transactions for fiscal years 2000 and 1999 were supported by documentation that was approved by management. The Commission recorded no donations, user fees, or in-kind donations for fiscal years 1999 and 2000. Also, the Commission's obligations exceeded its fiscal year 2000 appropriation of $600,000 by $29,729."
Date: October 22, 2001
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Characterizing the nano and micro structure of concrete to improve its durability (open access)

Characterizing the nano and micro structure of concrete to improve its durability

New and advanced methodologies have been developed to characterize the nano and microstructure of cement paste and concrete exposed to aggressive environments. High resolution full-field soft X-ray imaging in the water window is providing new insight on the nano scale of the cement hydration process, which leads to a nano-optimization of cement-based systems. Hard X-ray microtomography images on ice inside cement paste and cracking caused by the alkali-silica reaction (ASR) enables three-dimensional structural identification. The potential of neutron diffraction to determine reactive aggregates by measuring their residual strains and preferred orientation is studied. Results of experiments using these tools will be shown on this paper.
Date: October 22, 2008
Creator: Monteiro, P. J. M.; Kirchheim, A. P.; Chae, S.; Fischer, P.; MacDowell, A. A.; Schaible, E. et al.
Object Type: Article
System: The UNT Digital Library
Recent Searches for Exotic Physics at the BaBar/PEP-II B-factory (open access)

Recent Searches for Exotic Physics at the BaBar/PEP-II B-factory

I present three recent results from searches for exotic physics at the BABAR/PEP-II B-factory. These results span many of the samples produced at the B-factory, including B mesons, {tau} leptons, and {Upsilon}(3S) mesons. We have searched for CPT-violation in B{sup 0} mixing and find no significant deviation from the no-violation hypothesis. We have also searched for lepton-flavor-violating decays of the {tau} using {tau}{sup -} {yields} {omega}{ell}{sup -} and {tau}{sup -} {yields} {ell}{sup -}{ell}{sup +}{ell}{sup -} and their charge conjugates. We find no evidence for these processes and set upper limits on their branching fractions. Finally, we have searched for a low-mass Higgs boson in the decay {Upsilon}(3S) {yields} {gamma}A{sup 0}, where the Higgs decays invisibly. We find no evidence for such a decay and set upper limits across a range of possible Higgs masses.
Date: October 22, 2008
Creator: Sekula, Stephen Jacob
Object Type: Article
System: The UNT Digital Library
The National Ignition Facility: The world's largest optical system (open access)

The National Ignition Facility: The world's largest optical system

None
Date: October 22, 2007
Creator: Stolz, C J
Object Type: Article
System: The UNT Digital Library
Potential of Photovoltaics (open access)

Potential of Photovoltaics

Presented at the Association of Industrial Metallizers, Coaters and Laminators (AIMCAL) Fall Technical Conference 2008 and 22nd International Vacuum Web Coating Conference held October 19-22, 2008 in Myrtle Beach, South Carolina. This presentation discusses PV in the world energy portfolio, PV basics, PV technologies, and vacuum web-coating applications in PV.
Date: October 22, 2008
Creator: Nelson, B. P.
Object Type: Article
System: The UNT Digital Library
Scientific Needs for Future X-Ray Sources in the U.S.: A White Paper (open access)

Scientific Needs for Future X-Ray Sources in the U.S.: A White Paper

Many of the important challenges facing humanity, including developing alternative sources of energy and improving health, are being addressed by advances that demand the improved understanding and control of matter. While the visualization, exploration, and manipulation of macroscopic matter have long been technological goals, scientific developments in the twentieth century have focused attention on understanding matter on the atomic scale through the underlying framework of quantum mechanics. Of special interest is matter that consists of natural or artificial nanoscale building blocks defined either by atomic structural arrangements or by electron or spin formations created by collective correlation effects (Figure 1.1). The essence of the challenge to the scientific community has been expressed in five grand challenges for directing matter and energy recently formulated by the Basic Energy Sciences Advisory Committee. These challenges focus on increasing our understanding of, and ultimately control of, matter at the level of atoms, electrons, and spins, as illustrated in Figure 1.1. Meeting these challenges will require new tools that extend our reach into regions of higher spatial, temporal, and energy resolution. Since the fundamental interaction that holds matter together is of electromagnetic origin, it is intuitively clear that electromagnetic radiation is the critical tool in …
Date: October 22, 2008
Creator: Falcone , Roger; Stohr, Joachim; Bergmann, Uwe; Corlett, John; Galayda, John; Hastings, Jerry et al.
Object Type: Report
System: The UNT Digital Library
On The Reproducibility of Seasonal Land-surface Climate (open access)

On The Reproducibility of Seasonal Land-surface Climate

The sensitivity of the continental seasonal climate to initial conditions is estimated from an ensemble of decadal simulations of an atmospheric general circulation model with the same specifications of radiative forcings and monthly ocean boundary conditions, but with different initial states of atmosphere and land. As measures of the ''reproducibility'' of continental climate for different initial conditions, spatio-temporal correlations are computed across paired realizations of eleven model land-surface variables in which the seasonal cycle is either included or excluded--the former case being pertinent to climate simulation, and the latter to seasonal anomaly prediction. It is found that the land-surface variables which include the seasonal cycle are impacted only marginally by changes in initial conditions; moreover, their seasonal climatologies exhibit high spatial reproducibility. In contrast, the reproducibility of a seasonal land-surface anomaly is generally low, although it is substantially higher in the Tropics; its spatial reproducibility also markedly fluctuates in tandem with warm and cold phases of the El Nino/Southern Oscillation. However, the overall degree of reproducibility depends strongly on the particular land-surface anomaly considered. It is also shown that the predictability of a land-surface anomaly implied by its reproducibility statistics is consistent with what is inferred from more conventional predictability …
Date: October 22, 2004
Creator: Phillips, T J
Object Type: Article
System: The UNT Digital Library
U.S. and Russian Collaboration in the Area of Nuclear Forensics (open access)

U.S. and Russian Collaboration in the Area of Nuclear Forensics

Nuclear forensics has become increasingly important in the fight against illicit trafficking in nuclear and other radioactive materials. The illicit trafficking of nuclear materials is, of course, an international problem; nuclear materials may be mined and milled in one country, manufactured in a second country, diverted at a third location, and detected at a fourth. There have been a number of articles in public policy journals in the past year that call for greater interaction between the U. S. and the rest of the world on the topic of nuclear forensics. Some believe that such international cooperation would help provide a more certain capability to identify the source of the nuclear material used in a terrorist event. An improved international nuclear forensics capability would also be important as part of the IAEA verification toolkit, particularly linked to increased access provided by the additional protocol. A recent study has found that, although international progress has been made in securing weapons-usable HEU and Pu, the effort is still insufficient. They found that nuclear material, located in 40 countries, could be obtained by terrorists and criminals and used for a crude nuclear weapon. Through 2006, the IAEA Illicit Trafficking Database had recorded a …
Date: October 22, 2007
Creator: Kristo, M J
Object Type: Article
System: The UNT Digital Library
Diffusion of a Highly-Charged Supramolecular Assembly: Direct Observation of Ion-Association in Water (open access)

Diffusion of a Highly-Charged Supramolecular Assembly: Direct Observation of Ion-Association in Water

Understanding the solution behavior of supramolecular assemblies is essential for a full understanding of the formation and chemistry of synthetic host-guest systems. While the interaction between host and guest molecules is generally the focus of mechanistic studies of host-guest complexes, the interaction of the host-guest complex with other species in solution remains largely unknown, although in principle accessible by diffusion studies. Several NMR techniques are available to monitor diffusion and have recently been reviewed. Pulsed gradient spin-echo (PGSE) NMR methods have attracted increasing interest, since they allow diffusion coefficients to be measured with high accuracy; they have been successfully used with observation of {sup 7}Li and {sup 31}P nuclei as well as with {sup 1}H NMR. We report here the direct measurement of diffusion coefficients to observe ion-association interactions by counter cations with a highly-charged supramolecular assembly. Raymond and coworkers have described the design and chemistry of a class of metal-ligand supramolecular assemblies over the past decade. The [Ga{sub 4}L{sub 6}]{sup 12-} (L = 1,5-bis(2,3-dihydroxybenzamido)naphthalene) (1) (Figure 1) assembly has garnered the most attention, with the exploration of the dynamics and mechanism of guest exchange as well as the ability of 1 to achieve either stoichiometric or catalytic reactions inside …
Date: October 22, 2007
Creator: University of California, Berkeley; Laboratory, Lawrence Berkeley National; Raymond, Kenneth; Pluth, Michael D.; Tiedemann, Bryan E.F.; van Halbeek, Herman et al.
Object Type: Article
System: The UNT Digital Library
Final Report: Radiation-magnetohydrodynamic evolution and instability of conductors driven by megagauss magnetic fields (open access)

Final Report: Radiation-magnetohydrodynamic evolution and instability of conductors driven by megagauss magnetic fields

We are pleased to report important progress in experimentally characterizing and numerically modeling the transformation into plasma of walls subjected to pulsed megagauss magnetic fields. Understanding this is important to Magnetized Target Fusion (MTF) because an important limitation to the metal liner approach to MTF comes from the strong eddy current heating on the surface of the metal liner. This has intriguing non-linear aspects when the magnetic field is in the megagauss regime as needed for MTF, and may limit the magnetic field in an MTF implosion. Many faculty, students, and staff have contributed to this work, and, implicitly or explicitly, to this report. Contributors include, in addition to the PIs, Andrey Esaulov, Stephan Fuelling, Irvin Lindemuth, Volodymyr Makhin, Ioana Paraschiv, Milena Angelova, Tom Awe, Tasha Goodrich, Arunkumar Prasadam, Andrew Oxner, Bruno Le Galloudec, Radu Presura, and Vladimir Ivanov. Highlights of the progress made during the grant include: • 12 articles published, and 44 conference and workshop presentations made, on a broad range of issues related to this project; • An ongoing experiment that uses the 1 MA, 100-ns Zebra z-pinch at UNR to apply 2 5 megagauss to a variety of metal surfaces, examining plasma formation and evolution; • …
Date: October 22, 2008
Creator: Bauer, Bruno, S. & Siemon, Richard, E.
Object Type: Report
System: The UNT Digital Library
Monte Carlo Modeling and Analyses of Yalina- Booster Subcritical Assembly Part II : Pulsed Neutron Source. (open access)

Monte Carlo Modeling and Analyses of Yalina- Booster Subcritical Assembly Part II : Pulsed Neutron Source.

One of the most reliable experimental methods for measuring the kinetic parameters of a subcritical assembly is the Sjoestrand method applied to the reaction rate generated from a pulsed neutron source. This study developed a new analytical methodology for characterizing the kinetic parameters of a subcritical assembly using the Sjoestrand method, which allows comparing the analytical and experimental time dependent reaction rates and the reactivity measurements. In this methodology, the reaction rate, detector response, is calculated due to a single neutron pulse using MCNP/MCNPX computer code or any other neutron transport code that explicitly simulates the fission delayed neutrons. The calculation simulates a single neutron pulse over a long time period until the delayed neutron contribution to the reaction is vanished. The obtained reaction rate is superimposed to itself, with respect to the time, to simulate the repeated pulse operation until the asymptotic level of the reaction rate, set by the delayed neutrons, is achieved. The superimposition of the pulse to itself was calculated by a simple C computer program. A parallel version of the C program is used due to the large amount of data being processed, e.g. by the Message Passing Interface (MPI). The new calculation methodology has …
Date: October 22, 2008
Creator: Talamo, A.; Gohar, M. Y. A. & Rabiti, C.
Object Type: Report
System: The UNT Digital Library
Biosecurity Techbase FY07 Final Report (open access)

Biosecurity Techbase FY07 Final Report

This tech base award has close links with the Viral Identification Characterization Initiative (VICI) ER LDRD. The tech base extends developed code to enable a capability for biodefense, biosurveillance, and clinical diagnostics. The code enables the design of signatures to detect and discover viruses, without relying on prior assumptions as to the species of virus present. This approach for primer and signature design contrasts with more traditional PCR approaches, in which a major weakness is the unlikelihood of viral discovery or detection of unanticipated species. There were three crucial areas of the project that were not research and development, so could not be funded under the ER LDRD, but were a reduction to practice of the existing VICI algorithm that were necessary for the success of overall computational project goals. These areas, funded by the 2007 Tech Base award, were: (1) improvement of the code developed under the VICI LDRD by incorporating T{sub m} and free energy predictions using Unafold; (2) porting of code developed on the kpath Sun Solaris cluster to the Yana and Zeus LC machines; and (3) application of that code to perform large numbers of simulations to determine parameter effects.
Date: October 22, 2007
Creator: Gardner, S N & Williams, P L
Object Type: Report
System: The UNT Digital Library
Leveraging Structure to Improve Classification Performance in Sparsely Labeled Networks (open access)

Leveraging Structure to Improve Classification Performance in Sparsely Labeled Networks

We address the problem of classification in a partially labeled network (a.k.a. within-network classification), with an emphasis on tasks in which we have very few labeled instances to start with. Recent work has demonstrated the utility of collective classification (i.e., simultaneous inferences over class labels of related instances) in this general problem setting. However, the performance of collective classification algorithms can be adversely affected by the sparseness of labels in real-world networks. We show that on several real-world data sets, collective classification appears to offer little advantage in general and hurts performance in the worst cases. In this paper, we explore a complimentary approach to within-network classification that takes advantage of network structure. Our approach is motivated by the observation that real-world networks often provide a great deal more structural information than attribute information (e.g., class labels). Through experiments on supervised and semi-supervised classifiers of network data, we demonstrate that a small number of structural features can lead to consistent and sometimes dramatic improvements in classification performance. We also examine the relative utility of individual structural features and show that, in many cases, it is a combination of both local and global network structure that is most informative.
Date: October 22, 2007
Creator: Gallagher, B. & Eliassi-Rad, T.
Object Type: Report
System: The UNT Digital Library