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Financial Regulators: Agencies Have Implemented Key Performance Management Practices, but Opportunities for Improvement Exist

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Congress granted financial regulators flexibility to establish their own compensation systems and required certain agencies to seek to maintain comparability with each other in pay and benefits to help the agencies overcome impediments to recruiting and retaining employees and avoid competing for the same employees. In response to a request, this report reviews (1) how the performance-based pay systems … more
Date: June 18, 2007
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

United Nations Organizations: Oversight and Accountability Could Be Strengthened by Further Instituting International Best Practices

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Since 2005, the United Nations (UN) has been attempting to reform its management processes, in part to help ensure that resources are used effectively and efficiently. Some of these reforms focus on improving oversight and accountability at the United Nations. In this report, GAO examines the extent to which selected UN organizations' (1) internal audit offices have implemented professional standards fo… more
Date: June 18, 2007
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Coast Guard: Challenges Affecting Deepwater Asset Deployment and Management and Efforts to Address Them

Description: A letter report issued by the Government Accountability Office with an abstract that begins "The U.S. Coast Guard's Deepwater program was designed to replace aging vessels and aircraft and information capabilities with new and upgraded assets and equipment. GAO's prior work raised concerns about the Coast Guard's efforts to upgrade or acquire assets on schedule and manage the Deepwater prime contractor. This report responds to congressional direction contained in a conference report accompanyin… more
Date: June 18, 2007
Creator: United States. Government Accountability Office.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Modeling Incoherent Electron Cloud Effects

Description: Incoherent electron effects could seriously limit the beam lifetime in proton or ion storage rings, such as LHC, SPS, or RHIC, or blow up the vertical emittance of positron beams, e.g., at the B factories or in linear-collider damping rings. Different approaches to modeling these effects each have their own merits and drawbacks. We describe several simulation codes which simplify the descriptions of the beam-electron interaction and of the accelerator structure in various different ways, and pr… more
Date: June 18, 2007
Creator: Vay, Jean-Luc; Benedetto, E.; Fischer, W.; Franchetti, G.; Ohmi, K.; Schulte, D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Electron-Cloud Build-Up: Summary

Description: I present a summary of topics relevant to the electron-cloud build-up and dissipation that were presented at the International Workshop on Electron-Cloud Effects 'ECLOUD 07' (Daegu, S. Korea, April 9-12, 2007). This summary is not meant to be a comprehensive review of the talks. Rather, I focus on those developments that I found, in my personal opinion, especially interesting. The contributions, all excellent, are posted in http://chep.knu.ac.kr/ecloud07/.
Date: June 18, 2007
Creator: Furman, M. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement and Simulation of Source-Generated Halos in the University of Maryland Electron Ring (Umer)

Description: One of the areas of fundamental beam physics that have served as the rationale for recent research on UMER is the study of the generation and evolution of beam halos. Recent experiments and simulations have identified imperfections in the source geometry, particularly in the region near the emitter edge, as a significant potential source of halo particles. The edge-generated halo particles, both in the experiments and the simulations are found to pass through the center of the beam a short dist… more
Date: June 18, 2007
Creator: Haber, I.; Haber, I.; Bernal, S.; Kishek, R. A.; O'Shea, P. G.; Papadopoulos, C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Data-intensive computing laying foundation for biological breakthroughs

Description: Finding a different way is the goal of the Data-Intensive Computing for Complex Biological Systems (Biopilot) project—a joint research effort between the Pacific Northwest National Laboratory (PNNL) and Oak Ridge National Laboratory funded by the U.S. Department of Energy’s Office of Advanced Scientific Computing Research. The two national laboratories, both of whom are world leaders in computing and computational sciences, are teaming to support areas of biological research in urgent need of d… more
Date: June 18, 2007
Creator: Hachigian, David J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

EVALUATION OF RADIOLYSIS INDUCED HYDROGEN GENERATION IN DOT 6M DRUMS FROM INTEC

Description: Three DOT 6M 30-gallon drums are scheduled to be shipped from the Idaho Nuclear Technology Engineering Center (INTEC) at the Idaho National Laboratory (INL) to L-Area at the Savannah River Site (SRS). These three drums contain radioactive materials that resulted from the material recovery effort following a small explosion that had occurred in the Idaho Chemical Processing Plant (ICPP) hot chemistry laboratory (HCL). In support of the shipment and subsequent storage of the three DOT 6M drums, a… more
Date: June 18, 2007
Creator: Vinson, D
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

PORFLOW TESTING AND VERIFICATION DOCUMENT

Description: The PORFLOW software package is a comprehensive mathematical model for simulation of multi-phase fluid flow, heat transfer and mass transport in variably saturated porous and fractured media. PORFLOW can simulate transient or steady-state problems in Cartesian or cylindrical geometry. The porous medium may be anisotropic and heterogeneous and may contain discrete fractures or boreholes with the porous matrix. The theoretical models within the code provide a unified treatment of concepts relevan… more
Date: June 18, 2007
Creator: Aleman, S
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Modeling the Pulse Line Ion Accelerator (PLIA): an algorithm for quasi-static field solution.

Description: The Pulse-Line Ion Accelerator (PLIA) is a helical distributed transmission line. A rising pulse applied to the upstream end appears as a moving spatial voltage ramp, on which an ion pulse can be accelerated. This is a promising approach to acceleration and longitudinal compression of an ion beam at high line charge density. In most of the studies carried out to date, using both a simple code for longitudinal beam dynamics and the Warp PIC code, a circuit model for the wave behavior was employe… more
Date: June 18, 2007
Creator: Friedman, A; Briggs, R J; Grote, D P; Henestroza, E & Waldron, W L
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

INJECTOR PARTICLE SIMULATION AND BEAM TRANSPORT IN A COMPACT LINEAR PROTON ACCELERATOR

Description: A compact Dielectric Wall Accelerator (DWA), with field gradient up to 100 MW/m is being developed to accelerate proton bunches for use in cancer therapy treatment. The injector must create a proton pulse up to several hundred picoseconds, which is then shaped and accelerated with energies up to 250 MeV. The Particle-In-Cell (PIC) code LSP is used to model several aspects of this design. First, we use LSP to obtain the voltage waveform in the A-K gap that will produce a proton bunch with the re… more
Date: June 18, 2007
Creator: Blackfield, D. T.; Chen, Y. J.; Harris, J.; Nelson, S.; Paul, A. & Poole, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Baseline Configuration of the Cryogenic System for the International Linear Collider

Description: The paper discusses the main constraints and boundary conditions and describes the baseline configuration of the International Linear Collider (ILC) cryogenic system. The cryogenic layout, architecture and the cooling principle are presented. The paper addresses a plan for study and development required to demonstrate and improve the performance, to reduce cost and to attain the desired reliability.
Date: June 18, 2007
Creator: Casas-Cubillos, J.; Claudet, S.; Parma, V.; Riddone, G.; Serio, L.; Tavian, L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Recent RF Results from the MuCool Test Area

Description: The MuCool Experiment has been continuing to take data with805 and 201 MHz cavities in the MuCool Test Area. The system uses rfpower sources from the Fermilab Linac. Although the experimental programisprimarily aimed at the Muon Ionization Cooling Experiment (MICE), wehave been studying the dependence of rf limits on frequency, cavitymaterial, high magnetic fields, gas pressure, coatings, etc. with thegeneral aim of understanding the basic mechanisms involved. The 201 MHzcavity, essentially a p… more
Date: June 18, 2007
Creator: Norem, J.; Bross, A.; Moretti, A.; Qian, Z.; Huang, D.; Torun,Y. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Gate Drive For High Speed, High Power IGBTs

Description: A new gate drive for high-voltage, high-power IGBTs has been developed for the SLAC NLC (Next Linear Collider) Solid State Induction Modulator. This paper describes the design and implementation of a driver that allows an IGBT module rated at 800A/3300V to switch up to 3000A at 2200V in 3{micro}S with a rate of current rise of more than 10000A/{micro}S, while still being short circuit protected. Issues regarding fast turn on, high de-saturation voltage detection, and low short circuit peak curr… more
Date: June 18, 2007
Creator: Nguyen, M. N.; Cassel, R. L.; de Lamare, J. E. & Pappas, G. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Observation of the Long-Range Beam-Beam Effect in RHIC and Plans for Compensation

Description: At large distances the electromagnetic field of a wire is the same as the field produced by a bunch. Such a longrange beam-beam wire compensator was proposed for the LHC, and single beam tests with wire compensators were successfully done in the SPS. RHIC offers the possibility to test the compensation scheme with colliding beams. We report on measurements of beam losses as a function of transverse separation in RHIC at 100GeV, and comparisons with simulations. We present a design for a long-ra… more
Date: June 18, 2007
Creator: Fischer, W.; Calaga, R.; Dorda, U.; Koutchouk, J. P.; Zimmermann, F.; Kabel, A. C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Same-Sign Charginos And Majorana Neutralinos at the LHC

Description: We demonstrate the possibility of studying weakly interacting new particles in weak boson fusion, using the example of supersymmetric same-sign charginos. This signal can establish the existence of Majorana neutralinos and give access to their electroweak couplings. It can be observed over (supersymmetric) QCD backgrounds provided the charginos are light and not too close to the squark mass. We finally show how same-sign fermion production can be distinguished from samesign scalars or vectors a… more
Date: June 18, 2007
Creator: Alwall, Johan; Rainwater, Dave & Plehn, Tilman
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fast SCR Thyratron Driver

Description: As part of an improvement project on the linear accelerator at SLAC, it was necessary to replace the original thyratron trigger generator, which consisted of two chassis, two vacuum tubes, and a small thyratron. All solid-state, fast rise, and high voltage thyratron drivers, therefore, have been developed and built for the 244 klystron modulators. The rack mounted, single chassis driver employs a unique way to control and generate pulses through the use of an asymmetric SCR, a PFN, a fast pulse… more
Date: June 18, 2007
Creator: Nguyen, M. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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