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Telecommunications: National Broadband Plan Reflects the Experiences of Leading Countries, but Implementation Will Be Challenging

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Increasingly, broadband Internet service is seen as critical to a nation's physical infrastructure and economic growth. Universal access to, and increased use and adoption of, broadband service are policy goals stated in the National Broadband Plan, which the Federal Communications Commission (FCC) released in March 2010. Some recent studies indicate that despite achieving nearly 95 percent broadband de… more
Date: September 14, 2010
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Military Training: DOD Continues to Improve Its Report on the Sustainability of Training Ranges

Description: Correspondence issued by the Government Accountability Office with an abstract that begins "Recent operations in Iraq, Afghanistan, and other locations around the world have highlighted the need for U.S. forces to train as they intend to fight. Military training ranges provide the primary means to accomplish this goal. The Department of Defense's (DOD) training ranges vary in size from a few acres, for small arms training, to over a million acres for large maneuver exercises and weapons testing… more
Date: September 14, 2010
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
open access

Housing and Community Grants: HUD Needs to Enhance Its Requirements and Oversight of Jurisdictions' Fair Housing Plans

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Pursuant to the Fair Housing Act, Department of Housing and Urban Development (HUD) regulations require grantees, such as cities, that receive federal funds through the Community Development Block Grant (CDBG) and HOME Investment Partnerships Program (HOME) to further fair housing opportunities. In particular, grantees are required to prepare planning documents known as Analyses of Impediments (AI), whi… more
Date: September 14, 2010
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Public Transportation: Use of Contractors is Generally Enhancing Transit Project Oversight, and FTA is Taking Actions to Address Some Stakeholder Concerns

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Many states, cities, and localities are building or planning mass transit projects to meet the nation's transportation needs. The New Starts program--administered by the U.S. Department of Transportation's (DOT) Federal Transit Administration (FTA)--is an important source of new capital investment in mass transportation, providing grants to project sponsors (e.g., state and local government authorities)… more
Date: September 14, 2010
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Nuclear Waste: Actions Needed to Address Persistent Concerns with Efforts to Close Underground Radioactive Waste Tanks at DOE's Savannah River Site

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Decades of nuclear materials production at the Department of Energy's (DOE) Savannah River Site in South Carolina have left 37 million gallons of radioactive liquid waste in 49 underground storage tanks. In December 2008, DOE entered into a contract with Savannah River Remediation, LLC (SRR) to close, by 2017, 22 of the highest-risk tanks at a cost of $3.2 billion. GAO was asked to assess: (1) DOE's cos… more
Date: September 14, 2010
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

U.S. Periods of War

Description: Many wars or conflicts in U.S. history have federally designated "periods of war," dates marking their beginning and ending. This report lists the beginning and ending dates for "periods of war" found in Title 38 of the Code of Federal Regulations, dealing with the Department of Veterans Affairs (VA). It also lists and differentiates other beginning dates given in declarations of war, as well as termination of hostilities dates and armistice and ending dates given in proclamations, laws, or tre… more
Date: September 14, 2010
Creator: Torreon, Barbara Salazar
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Saving Rates in the United States: Calculation and Comparison

Description: The amount of money saved has important economic consequences. Nationally, the amount of saving affects how much can be invested and ultimately the size of the capital stock. This report explains how national saving is measured, presents recent estimates of saving rates in the United States, and, for comparison, provides those of other major industrial countries.
Date: September 14, 2010
Creator: Elwell, Craig K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

State Efforts to Deter Unauthorized Aliens: Legal Analysis of Arizona's S.B. 1070

Description: On April 23, 2010, Arizona enacted S.B. 1070, which is designed to discourage and deter the entry or presence of aliens who lack lawful status under federal immigration law. This report discusses this piece of legislation and some of the notable preemption issues raised by its provisions. Where relevant, it examines the district court's ruling that the federal government is likely to succeed on the merits of its arguments that certain sections of S.B. 1070 are preempted by federal law. It also … more
Date: September 14, 2010
Creator: Manuel, Kate M.; Garcia, Michael John & Eig, Larry M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mortgage Financing: Opportunities to Enhance Management and Oversight of FHA's Financial Condition

Description: Correspondence issued by the Government Accountability Office with an abstract that begins "The Department of Housing and Urban Development's (HUD) Federal Housing Administration (FHA) has helped millions of families purchase homes through its single-family mortgage insurance programs. In recent years, FHA has experienced a dramatic increase in its market role due to the contraction of other mortgage market segments. FHA insures almost all of its single-family mortgages under its Mutual Mortgag… more
Date: September 14, 2010
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
open access

Running Deficits: Positives and Pitfalls

Description: The FY2009 federal deficit swelled to $1.414 trillion, or nearly 10% of gross domestic product (GDP), due to the economic recession. The size of recent deficits has added to longstanding concerns regarding the federal government's long-term fiscal condition. However, deficit finance can serve as an important policy tool. This report discusses how deficit finance can help governments manage their economies and how large and persistent deficits can lead to severe economic problems.
Date: September 14, 2010
Creator: Austin, D. Andrew
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Powerful, Efficient Electric Vehicle Chargers: Low-Cost, Highly-Integrated Silicon Carbide (SiC) Multichip Power Modules (MCPMs) for Plug-In Hybrid Electric

Description: ADEPT Project: Currently, charging the battery of an electric vehicle (EV) is a time-consuming process because chargers can only draw about as much power from the grid as a hair dryer. APEI is developing an EV charger that can draw as much power as a clothes dryer, which would drastically speed up charging time. APEI's charger uses silicon carbide (SiC)-based power transistors. These transistors control the electrical energy flowing through the charger's circuits more effectively and efficientl… more
Date: September 14, 2010
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
open access

Development of a System for Rapid Detection of Contaminants in Water Supplies Using Magnetic Resonance and Nanoparticles

Description: To keep the water supply safe and to ensure a swift and accurate response to a water supply contamination event, rapid and robust methods for microbial testing are necessary. Current technologies are complex, lengthy and costly and there is a need for rapid, reliable, and precise approaches that can readily address this fundamental security and safety issue. T2 Biosystems is focused on providing solutions to this problem by making breakthroughs in nanotechnology and biosensor techniques that ad… more
Date: September 14, 2010
Creator: Lowery, Thomas J; Neely, Lori; Chepin, James; Wellman, Parris; Toso, Ken; Murray, Paul et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Echo-seeding options for LCLS-II

Description: The success of LCLS has opened up a new era of x-ray sciences. An upgrade to LCLS is currently being planned to enhance its capabilities. In this paper we study the feasibility of using the echo-enabled harmonic generation (EEHG) technique to generate narrow bandwidth soft x-ray radiation in the proposed LCLS-II soft x-ray beam line. We focus on the conceptual design, the technical implementation and the expected performances of the echo-seeding scheme. We will also show how the echo-seeding sc… more
Date: September 14, 2010
Creator: Xiang, Dao
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Design of the Second-Generation ILC Marx Modulator

Description: SLAC National Accelerator Laboratory (SLAC) has initiated a program to design and build a Marx-topology modulator to produce a relatively compact, low-cost, high availability klystron modulator for the International Linear Collider (ILC). Building upon the success of the P1 Marx, the SLAC P2 Marx is a second-generation modulator whose design further emphasizes the qualities of modularity and high-availability. This paper outlines highlights of this design and presents single-cell performance da… more
Date: September 14, 2010
Creator: Kemp, M. A.; Benwell, A.; Burkhart, C.; Larsen, R.; MacNair, D.; Nguyen, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Early Events in Ionic Liquid Radiation Chemistry

Description: Ionic liquids are interesting and useful materials whose solvation time scales are up to thousands of times longer than in conventional solvents. The extended lifetimes of pre-solvated electrons and other energetic species in ionic liquids has profound consequences for the radiolytic product distributions and reactivity patterns. We use a newly developed, multiplexed variation of pulse-probe spectroscopy to measure the kinetics of the early dynamical and reactive events in ionic liquids.
Date: September 14, 2010
Creator: Wishart, J. F.; Cook, A.; Rimmer, R. D. & Gohdo, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Characterization of Second Harmonic Afterburner Radiation at the LCLS

Description: During commissioning of the Linac Coherent Light Source (LCLS) x-ray Free Electron Laser (FEL) at the SLAC National Accelerator Laboratory it was shown that saturation lengths much shorter than the installed length of the undulator line can routinely be achieved. This frees undulator segments that can be used to provide enhanced spectral properties and at the same time, test the concept of FEL Afterburners. In December 2009 a project was initiated to convert undulator segments at the down-beam … more
Date: September 14, 2010
Creator: Nuhn, Heinz-Dieter
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Monte Carlo Studies of the Radiation Fields in the Linac Coherent Light Source Undulators and of the Corresponding Signals in the Cerenkov Beam Loss Monitors

Description: In 2009 the Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Center started free electron laser (FEL) operation. In order to continue to produce the bright and short-pulsed x-ray laser demanded by FEL scientists, this pioneer hard x-ray FEL requires a perfectly tailored magnetic field at the undulators, so that the photons generated at the electron wiggling path interact at the right phase with the electron beam. In such a precise system, small (>0.01%) radiation-induced a… more
Date: September 14, 2010
Creator: Santana Leitner, Mario
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

LHC Beam Diffusion Dependence on RF Noise: Models And Measurements

Description: Radio Frequency (RF) accelerating system noise and non-idealities can have detrimental impact on the LHC performance through longitudinal motion and longitudinal emittance growth. A theoretical formalism has been developed to relate the beam and RF loop dynamics with the bunch length growth [1]. Measurements were conducted at LHC to validate the formalism, determine the performance limiting RF components, and provide the foundation for beam diffusion estimates for higher energies and intensitie… more
Date: September 14, 2010
Creator: Mastorides, T.; Rivetta, C.; Fox, J. D.; Van Winkle, D.; Baudrenghien, P.; Butterworth, A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Precise Predictions for W 4 Jet Production at the Large Hadron Collider

Description: We present the first next-to-leading order QCD results for W + 4-jet production at hadron colliders. Total cross sections, as well as distributions in the jet transverse momenta and in the total transverse energy HT, are provided for the initial LHC energy of {radical}s = 7 TeV. We use a leading-color approximation, known to be accurate to 3% for W production with fewer jets. The virtual matrix elements and the most complicated real-emission matrix elements are handled by the BlackHat library, … more
Date: September 14, 2010
Creator: Berger, C.F.; /MIT, LNS; Bern, Z.; /UCLA; Dixon, Lance J.; /SLAC, /CERN et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Three-Dimensional Analysis of Frequency-Chirped FELs

Description: Frequency-chirped free-electron lasers (FELs) are useful to generate a large photon bandwidth or a shorter x-ray pulse duration. In this paper, we present a three-dimensional analysis of a high-gain FEL driven by the energy-chirped electron beam. We show that the FEL eigenmode equation is the same for a frequency-chirped FEL as for an undulator-tapered FEL. We study the transverse effects of such FELs including mode properties and transverse coherence.
Date: September 14, 2010
Creator: Zhirong, Huang
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

LHC RF System Time-Domain Simulation

Description: Non-linear time-domain simulations have been developed for the Positron-Electron Project (PEP-II) and the Large Hadron Collider (LHC). These simulations capture the dynamic behavior of the RF station-beam interaction and are structured to reproduce the technical characteristics of the system (noise contributions, non-linear elements, and more). As such, they provide useful results and insight for the development and design of future LLRF feedback systems. They are also a valuable tool for the s… more
Date: September 14, 2010
Creator: Mastorides, T. & Rivetta, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Algorithm for Computation of Electromagnetic Fields of An Accelerated Short Bunch Inside a Rectangular Chamber

Description: We discuss the feasibility of an application of an implicit finite-difference approximation to calculate the fields of a relativistic bunch moving with no restriction inside a vacuum chamber. We assume that a bunch trajectory is not straight but is inside a vacuum chamber or its branch. The bunch can be deflected by the fields of bending magnets. The bunch can be short enough to produce coherent synchrotron radiation (CSR). Accelerator physicists believe that electromagnetic phenomena of charge… more
Date: September 14, 2010
Creator: Novokhatski, Alexander & Sullivan, Michael
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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