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Arizona Border Surveillance Technology: More Information on Plans and Costs Is Needed before Proceeding (open access)

Arizona Border Surveillance Technology: More Information on Plans and Costs Is Needed before Proceeding

A letter report issued by the Government Accountability Office with an abstract that begins "In recent years, nearly half of all annual apprehensions of illegal aliens along the entire Southwest border with Mexico have occurred along the Arizona border. Keeping illegal flows of people and drugs under control remains a top priority for the Department of Homeland Security's (DHS) U.S. Customs and Border Protection (CBP). In 2005, the Secure Border Initiative Network (SBInet) was conceived as a surveillance technology to create a "virtual fence" along the border. After spending nearly $1 billion, DHS deployed SBInet systems along 53 miles of Arizona's border that represent the highest risk for illegal entry. In January 2011, in response to concerns regarding SBInet's performance, cost, and schedule, DHS cancelled future procurements. CBP developed the Arizona Border Surveillance Technology Plan (Plan) for the remainder of the Arizona border. Funding for this Plan for fiscal year 2012 is $242 million. GAO was requested to assess the extent to which CBP (1) has the information needed to support and implement the Plan and (2) estimated life-cycle costs for future investments in accordance with best practices. GAO analyzed Plan documents and cost estimates, compared those estimates with best …
Date: November 4, 2011
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Vacant Properties: Growing Number Increases Communities' Costs and Challenges (open access)

Vacant Properties: Growing Number Increases Communities' Costs and Challenges

A letter report issued by the Government Accountability Office with an abstract that begins "Vacant and unattended residential properties can attract crime, cause blight, and pose a threat to public safety. While homeowners or mortgage owners--including the mortgage servicers that administer loans on behalf of loan owners--are responsible for maintaining vacant properties with mortgages undergoing foreclosure, the costs local governments incur to mitigate any unsafe conditions can be significant. GAO was asked to examine (1) trends in the number of vacant properties and how they relate to the recent increase in foreclosures, (2) the types of costs that vacant properties create and who bears the responsibility for these properties and their costs, and (3) state and local government strategies to address vacant properties and the federal role in assisting these efforts. GAO analyzed Census Bureau vacancy data and data on property maintenance costs from the Federal Housing Administration (FHA) and two housing-related government-sponsored enterprises (GSE). GAO conducted case studies in nine cities selected to provide a range of local economic and housing conditions, rates of foreclosure, and geographic locations. GAO also interviewed local officials, representatives of community development organizations, federal agencies, and mortgage servicers, among others. The Federal Reserve, Census, …
Date: November 4, 2011
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Federal Courthouse Construction: Nationwide Space and Cost Issues Are Applicable to L.A. Courthouse Project (open access)

Federal Courthouse Construction: Nationwide Space and Cost Issues Are Applicable to L.A. Courthouse Project

Testimony issued by the Government Accountability Office with an abstract that begins "In 2000, as part of a multibillion-dollar courthouse construction initiative, the judiciary requested and the General Services Administration (GSA) proposed building a new courthouse in Los Angeles to increase security, efficiency, and space--but construction never began. About $400 million was appropriated for the L.A. courthouse project. For this testimony, GAO was asked to report on (1) the status of the L.A. courthouse project, (2) challenges GAO has identified affecting federal courthouses nationwide, and (3) the extent to which these challenges are applicable to the L.A. courthouse project. This testimony is based on GAO-10-417 and GAO's other prior work on federal courthouses, during which GAO analyzed courthouse planning and use data, visited courthouses, modeled courtroom sharing scenarios, and interviewed judges, GSA officials, and others. In GAO-10-417, GAO recommended that (1) GSA ensure that new courthouses are constructed within their authorized size or, if not, that congressional committees are notified, (2) the Judicial Conference of the United States retain caseload projections to improve the accuracy of its 10-year-judge planning, and (3) the Conference establish and use courtroom sharing policies based on scheduling and use data. GSA and the judiciary agreed …
Date: November 4, 2011
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Initial Pilot Training: Better Management Controls Are Needed to Improve FAA Oversight (open access)

Initial Pilot Training: Better Management Controls Are Needed to Improve FAA Oversight

A letter report issued by the Government Accountability Office with an abstract that begins "Regional airlines have experienced the last six fatal commercial airline accidents, and pilot performance has been cited as a potential contributory factor in four of these accidents. As a result, Congress and others have raised questions about, among other issues, the initial pilot education and training required before pilots can be hired by airlines, at which time they receive further training. The initial training is provided by pilot schools overseen by the Federal Aviation Administration (FAA). As requested, this report discusses (1) the various types of U.S. pilot schools, how they compare, and associated issues; (2) key similarities and differences between the U.S. and international approaches to pilot training; and (3) how and to what extent FAA carries out oversight of pilot training and certification. To address these issues, GAO reviewed literature, legislation, regulations, and FAA documents and inspection and enforcement data; interviewed agency and industry officials; and studied the training approach in Europe because of the different training model and visited four European countries."
Date: November 4, 2011
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
The Greensheet (Houston, Tex.), Vol. 42, No. 478, Ed. 1 Friday, November 4, 2011 (open access)

The Greensheet (Houston, Tex.), Vol. 42, No. 478, Ed. 1 Friday, November 4, 2011

Free weekly newspaper that includes business and classified advertising.
Date: November 4, 2011
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Houston, Tex.), Vol. 42, No. 480, Ed. 1 Friday, November 4, 2011 (open access)

The Greensheet (Houston, Tex.), Vol. 42, No. 480, Ed. 1 Friday, November 4, 2011

Free weekly newspaper that includes business and classified advertising.
Date: November 4, 2011
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Optimist (Abilene, Tex.), Vol. 100, No. 20, Ed. 1 Friday, November 4, 2011 (open access)

The Optimist (Abilene, Tex.), Vol. 100, No. 20, Ed. 1 Friday, November 4, 2011

Bi-weekly student newspaper from Abilene Christian University in Abilene, Texas that includes local, state and campus news along with advertising.
Date: November 4, 2011
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Texas Register, Volume 36, Number 44, Pages 7417-7610, November 4, 2011 (open access)

Texas Register, Volume 36, Number 44, Pages 7417-7610, November 4, 2011

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: November 4, 2011
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Dallas Voice (Dallas, Tex.), Vol. 28, No. 25, Ed. 1 Friday, November 4, 2011 (open access)

Dallas Voice (Dallas, Tex.), Vol. 28, No. 25, Ed. 1 Friday, November 4, 2011

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: November 4, 2011
Creator: Nash, Tammye
Object Type: Newspaper
System: The UNT Digital Library
Permanent Normal Trade Relations (PNTR) Status for Russia and U.S.-Russian Economic Ties (open access)

Permanent Normal Trade Relations (PNTR) Status for Russia and U.S.-Russian Economic Ties

None
Date: November 4, 2011
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Simplifying Multi-Jet QCD Computation (open access)

Simplifying Multi-Jet QCD Computation

These lectures give a pedagogical discussion of the computation of QCD tree amplitudes for collider physics. The tools reviewed are spinor products, color ordering, MHV amplitudes, and the Britto-Cachazo-Feng-Witten recursion formula.
Date: November 4, 2011
Creator: Peskin, Michael E.
Object Type: Article
System: The UNT Digital Library
Quarkonium Spectroscopy And Search for New States at BaBar (open access)

Quarkonium Spectroscopy And Search for New States at BaBar

The BaBar experiment at the PEP-II B-factory gives excellent opportunities for the quarkonium spectroscopy. Investigation of the properties of new states like the X(3872), Y(3940) and Y(4260) are performed aiming to understand their nature. Recent BaBar results will be presented in this paper. At the B-factories charmonium and charmonium-like states are copiously produced via several mechanisms: in B decay (color suppressed b {yields} c transition), double charmonium production (e{sup +}e{sup -} {yields} c{bar c} + c{bar c}), two photons production ({gamma}*{gamma}* {yields} c{bar c}, where the c{bar c} state has positive C-parity) and in initial state radiation (ISR) when the e{sup {+-}} in its initial state emits a photon lowering the effective center of mass energy of the e{sup +}e{sup -} interaction (e{sup +}e{sup -} {yields} {gamma}{sub ISR} + c{bar c}, where the charmonium state has the quantum numbers J{sup PC} = 1{sup -2}). Many new states have been recently discovered at the B-factories, BaBar and Belle, above the D{bar D} threshold in the charmonium energy region. While some of them appear to be consistent with conventional c{sub c} states others do not fit with any expectation. Several interpretations for these states have been proposed: for some of them the …
Date: November 4, 2011
Creator: Cibinetto, G.
Object Type: Article
System: The UNT Digital Library
Copper Prototype Measurements of the HOM, LOM And SOM Couplers for the ILC Crab Cavity (open access)

Copper Prototype Measurements of the HOM, LOM And SOM Couplers for the ILC Crab Cavity

The ILC Crab Cavity is positioned close to the IP and delivered luminosity is very sensitive to the wakefields induced in it by the beam. A set of couplers were designed to couple to and damp the spurious modes of the crab cavity. As the crab cavity operates using a dipole mode, it has different damping requirements from an accelerating cavity. A separate coupler is required for the monopole modes below the operating frequency of 3.9 GHz (known as the LOMs), the opposite polarization of the operating mode (the SOM), and the modes above the operating frequency (the HOMs). Prototypes of each of these couplers have been manufactured out of copper and measured attached to an aluminum nine cell prototype of the cavity and their external Q factors were measured. The results were found to agree well with numerical simulations.
Date: November 4, 2011
Creator: Burt, G.; Ambattu, P.K.; Dexter, A.C.; U., /Lancaster; Bellantoni, L.; /Fermilab et al.
Object Type: Article
System: The UNT Digital Library
Amorphous Diamond - A High-pressure Superhard Carbon Allotrope (open access)

Amorphous Diamond - A High-pressure Superhard Carbon Allotrope

This report is about the Amorphous Diamond - A High-pressure Superhard Carbon Allotrope
Date: November 4, 2011
Creator: Lin, Yu
Object Type: Article
System: The UNT Digital Library
Status of High Power Tests of Normal Conducting Single-Cell Structures (open access)

Status of High Power Tests of Normal Conducting Single-Cell Structures

We report the results of ongoing high power tests of single-cell standing wave structures. These tests are part of an experimental and theoretical study of rf breakdown in normal conducting structures at 11.4 GHz. The goal of this study is to determine the maximum gradient possibilities for normal-conducting rf powered particle beam accelerators. The test setup consists of reusable mode launchers and short test structures powered by SLACs XL-4 klystron. The mode launchers and structures were manufactured at SLAC and KEK and tested at the SLAC klystron test laboratory.
Date: November 4, 2011
Creator: Dolgashev, V. A.; Tantawi, S. G.; Higashi, Y. & Higo, T.
Object Type: Article
System: The UNT Digital Library
Sensible Heat, Direct, Dual-Media Thermal Energy Storagy System: Phase 1 Final Technical Report (open access)

Sensible Heat, Direct, Dual-Media Thermal Energy Storagy System: Phase 1 Final Technical Report

Work under this project has ultimately focused on the development of a modular packed bed based thermal energy storage system. The design assumes the use of standard segments of carbon steel pipe filled with spherical materials creating a packed bed. These materials are assumed to be manufactured in such a way that the spherical shape is uniform throughout the packed bed. Out of 32 candidate materials evaluated, 8 materials remain. Each material meets the Phase I milestones that were specified for this storage system: a round trip efficiency in excess of 93%, and a required volume of packed bed material that does not exceed the volume of molten salt used in a two-tank storage system with equivalent thermal performance.
Date: November 4, 2011
Creator: Newmarker, Marc & Campbell, Mark
Object Type: Report
System: The UNT Digital Library
Experimental Study of Synchro-Betatron Coupling Induced By Dipole Modulation (open access)

Experimental Study of Synchro-Betatron Coupling Induced By Dipole Modulation

Synchro-betatron coupling in a proton storage ring with electron cooling was studied experimentally by modulating a transverse dipole field close to the synchrotron frequency. The combination of the electron cooling and transverse field modulation on the synchrotron oscillation is equivalent to a dissipative parametric resonant system. The proton bunch was observed to split longitudinally into two pieces, or beamlets, converging toward attractors of the dissipative system. These phenomena might be important in understanding the effect of ground vibration on the Superconducting Super Collider beam, and the effect of power supply ripple on the Relativistic Heavy-Ion Collider beam.
Date: November 4, 2011
Creator: Syphers, M.; Ball, M.; Brabson, B.; Budnick, J.; Caussyn, D. D.; Chao, A. W. et al.
Object Type: Article
System: The UNT Digital Library
Observations and Modeling of Debris and Shrapnel Impacts on Optics and Diagnostics at the National Ignition Facility (open access)

Observations and Modeling of Debris and Shrapnel Impacts on Optics and Diagnostics at the National Ignition Facility

A wide range of targets with laser energies spanning two orders of magnitude have been shot at the National Ignition Facility (NIF). The National Ignition Campaign (NIC) targets are cryogenic with Si supports and cooling rings attached to an Al thermo-mechanical package (TMP) with a thin (30 micron) Au hohlraum inside. Particular attention is placed on the low-energy shots where the TMP is not completely vaporized. In addition to NIC targets, a range of other targets has also been fielded on NIF. For all targets, simulations play a critical role in determining if the risks associated with debris and shrapnel are acceptable. In a number of cases, experiments were redesigned, based on simulations, to reduce risks or to obtain data. The majority of these simulations were done using the ALE-AMR code, which provides efficient late-time (100-1000X the pulse duration) 3D calculations of complex NIF targets.
Date: November 4, 2011
Creator: Eder, D.; Bailey, D.; Chamgers, F.; Darnell, I.; Nicola, P. D.; Dixit, S. et al.
Object Type: Article
System: The UNT Digital Library
Recent Upgrade of the Klystron Modulator at SLAC (open access)

Recent Upgrade of the Klystron Modulator at SLAC

The SLAC National Accelerator Laboratory employs 244 klystron modulators on its two-mile-long linear accelerator that has been operational since the early days of the SLAC establishment in the sixties. Each of these original modulators was designed to provide 250 kV, 262 A and 3.5 {mu}S at up to 360 pps using an inductance-capacitance resonant charging system, a modified type-E pulse-forming network (PFN), and a pulse transformer. The modulator internal control comprised of large step-start resistor-contactors, vacuum-tube amplifiers, and 120 Vac relays for logical signals. A major, power-component-only upgrade, which began in 1983 to accommodate the required beam energy of the SLAC Linear Collider (SLC) project, raised the modulator peak output capacity to 360 kV, 420 A and 5.0 {mu}S at a reduced pulse repetition rate of 120 pps. In an effort to improve safety, performance, reliability and maintainability of the modulator, this recent upgrade focuses on the remaining three-phase AC power input and modulator controls. The upgrade includes the utilization of primary SCR phase control rectifiers, integrated fault protection and voltage regulation circuitries, and programmable logic controllers (PLC) -- with an emphasis on component physical layouts for safety and maintainability concerns. In this paper, we will describe the design and …
Date: November 4, 2011
Creator: Nguyen, M. N.; Burkhart, C. P.; Lam, B. K. & Morris, B.
Object Type: Article
System: The UNT Digital Library
Scattering Amplitudes: The Most Perfect Microscopic Structures in the Universe (open access)

Scattering Amplitudes: The Most Perfect Microscopic Structures in the Universe

This article gives an overview of many of the recent developments in understanding the structure of relativistic scattering amplitudes in gauge theories ranging from QCD to N = 4 super-Yang-Mills theory, as well as (super)gravity. I also provide a pedagogical introduction to some of the basic tools used to organize and illuminate the color and kinematic structure of amplitudes. This article is an invited review introducing a special issue of Journal of Physics A devoted to 'Scattering Amplitudes in Gauge Theories'.
Date: November 4, 2011
Creator: Dixon, Lance J. & /SLAC, /CERN
Object Type: Article
System: The UNT Digital Library
The Design of the Positron Source for the International Linear Collider (open access)

The Design of the Positron Source for the International Linear Collider

The high luminosity requirements and the option of a polarized positron beam present a great challenge for the positron source of a future linear collider. This paper provides a comprehensive overview of the latest proposed design for the baseline positron source of the International Linear Collider (ILC). We report on recent progress and results concerning the main components of the source: including the undulator, capture optics, and target.
Date: November 4, 2011
Creator: Clarke, J. A.; Malyshev, O. B.; Scott, D. J.; Bailey, I. R.; Dainton, J. B.; Hock, K. M. et al.
Object Type: Article
System: The UNT Digital Library
Study for ILC Damping Ring at KEKB (open access)

Study for ILC Damping Ring at KEKB

ILC damping ring consists of very low emittance electron and positron storage rings. It is necessary for ILC damping ring to study electron cloud effects in such low emittance positron ring. We propose a low emittance operation of KEKB to study the effects.
Date: November 4, 2011
Creator: Flanagan, J. W.; Fukuma, H.; Kanazawa, K. I.; Koiso, H.; Masuzawa, M.; Ohmi, Kazuhito et al.
Object Type: Article
System: The UNT Digital Library
Reducing Memory Cost of Exact Diagonalization using Singular Value Decomposition (open access)

Reducing Memory Cost of Exact Diagonalization using Singular Value Decomposition

We present a modified Lanczos algorithm to diagonalize lattice Hamiltonians with dramatically reduced memory requirements. The lattice of size N is partitioned into two subclusters. At each iteration the Lanczos vector is projected into a set of n{sub svd} smaller subcluster vectors using singular value decomposition. For low entanglement entropy S{sub ee}, (satisfied by short range Hamiltonians), we expect the truncation error to vanish as exp(-n{sup 1/S{sub ee}}{sub svd}). Convergence is tested for the Heisenberg model on Kagome clusters of up to 36 sites, with no symmetries exploited, using less than 15GB of memory. Generalization to multiple partitioning is discussed.
Date: November 4, 2011
Creator: Weinstein, Marvin; Auerbach, Assa & Chandra, V. Ravi
Object Type: Article
System: The UNT Digital Library
Virtual Scanning Tunneling Microscopy: A Local Spectroscopic Probe of 2D Electron Systems (open access)

Virtual Scanning Tunneling Microscopy: A Local Spectroscopic Probe of 2D Electron Systems

None
Date: November 4, 2011
Creator: Sciambi, A.; Pelliccione, M.; Bank, S.R.; Gossard, A.C. & Goldhaber-Gordon, D.
Object Type: Article
System: The UNT Digital Library