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MPX: software for multiplexing hardware performance counters in multithreaded programs

Description: Hardware performance counters are CPU registers that count data loads and stores, cache misses, and other events. Counter data can help programmers understand software performance. Although CPUs typically have multiple counters, each can monitor only one type of event at a time, and some counters can monitor only certain events. Therefore, some CPUs cannot concurrently monitor interesting combinations of events. Software multiplexing partly overcomes this limitation by using time sharing to monitor multiple events on one counter: However; counter multiplexing is harder to implement for multithreaded programs than for single-threaded ones because of certain difficulties in managing the length of the time slices. This paper describes a software library called MPX that overcomes these difficulties. MPX allows applications to gather hardware counter data concurrently for any combination of countable events. MPX data are typically within a few percent of counts recorded without multiplexing.
Date: January 8, 2001
Creator: May, J M
Partner: UNT Libraries Government Documents Department

Non-Intrusive Load Monitoring Assessment: Literature Review and Laboratory Protocol

Description: To evaluate the accuracy of NILM technologies, a literature review was conducted to identify any test protocols or standardized testing approaches currently in use. The literature review indicated that no consistent conventions were currently in place for measuring the accuracy of these technologies. Consequently, PNNL developed a testing protocol and metrics to provide the basis for quantifying and analyzing the accuracy of commercially available NILM technologies. This report discusses the results of the literature review and the proposed test protocol and metrics in more detail.
Date: July 1, 2013
Creator: Butner, R. Scott; Reid, Douglas J.; Hoffman, Michael G.; Sullivan, Greg & Blanchard, Jeremy
Partner: UNT Libraries Government Documents Department

PACE and the Federal Housing Finance Agency (FHFA)

Description: The FHFA regulates Fannie Mae, Freddie Mac, and the 12 Federal Home Loan Banks (the government-sponsored enterprises - GSEs). On June 18, 2009, James B. Lockhart III, then Director of FHFA, released a letter expressing concern about the negative impact of energy loan tax assessment programs (ELTAPs) - also known as Property Assessed Clean Energy (PACE) programs - on both the housing finance system and homeowner program participants. Subsequently, a number of PACE proponents responded to the concerns laid out in the FHFA letter. In early Fall 2009, word circulated that FHFA was planning to follow its June letter with guidance to other agencies, possibly including Fannie Mae and Freddie Mac, discouraging them from buying loans on properties subject to PACE-type assessment liens. This triggered a second round of stakeholder letters, several of which were addressed to President Obama. On October 18, 2009, the White House, in what some believe was an attempt to obviate the need for FHFA guidance, released a Policy Framework for PACE Financing Programs that outlined best practices guidance for homeowner and lender protection. As of February 2010, FHFA and the GSEs have agreed to monitor PACE programs and work with stakeholders and the Administration to consider additional guidance beyond the Policy Framework and to collect more information on PACE program efficacy and risks. A summary of the communications timeline and highlights of the communications are provided.
Date: March 17, 2010
Creator: Zimring, Mark & Fuller, Merrian
Partner: UNT Libraries Government Documents Department

Beam Loss Monitors in the NSLS Storage Rings

Description: Beam loss monitors (BLM) have been used for more than two decades in the VUV ring at the NSLS. These have proved useful for optimizing injection and operation of the ring. Recently similar monitors have been installed in the X-ray ring and are being used to better understand injection, as well as operation of the ring. These units have been compared with the Bergoz BLMs, which have been mostly useful for understanding operating beam losses.
Date: May 4, 2009
Creator: Kramer,S.L. & Fedurin, M.
Partner: UNT Libraries Government Documents Department

Statistical process control (SPC) for coordinate measurement machines

Description: The application of process capability analysis, using designed experiments, and gage capability studies as they apply to coordinate measurement machine (CMM) uncertainty analysis and control will be demonstrated. The use of control standards in designed experiments, and the use of range charts and moving range charts to separate measurement error into it's discrete components will be discussed. The method used to monitor and analyze the components of repeatability and reproducibility will be presented with specific emphasis on how to use control charts to determine and monitor CMM performance and capability, and stay within your uncertainty assumptions.
Date: January 4, 2000
Creator: Escher, R. N.
Partner: UNT Libraries Government Documents Department

Shock Initiation of New and Aged PBX 9501 Measured with Embedded Electromagnetic Particle Velocity Gauges

Description: We have used an embedded electromagnetic particle velocity gauge technique to measure the shock initiation behavior in PBX 9501 explosive. Up to twelve separate particle velocity wave profile measurements have been made at different depths in a single experiment. These detail the growth from an input shock to a detonation. In addition, another gauge element called a ''shock tracker'' has been used to monitor the progress of the shock front as a function of time and position as it moves through the explosive sample. This provides data similar to that obtained in a traditional explosively driven wedge test and is used to determine the position and time that the wave attains detonation. Run distance-to-detonation vs. input pressure (Pop-plot) data and particle velocity wave profile data have been obtained on new PBX 9501 pressed to densities of 1.826, 1.830, and 1.837 g/cm{sup 3}. In addition, the same measurements were performed on aged material recovered from dismantled W76 and W78 weapons. The input pressure range covered was 3.0 to 5.2 GPa. All results to date show shock sensitivity to be a function only of the initial density and not of age. PBX 9501 shock initiates the same after 17 years in stockpile as it does on the day it is pressed. Particle velocity wave profiles show mixed heterogeneous initiation (growth in the front) and homogeneous initiation (growth behind the front).
Date: September 1, 1999
Creator: Hill, L. G.; Gustavsen, R. L.; Alcon, R. R. & Sheffield, S. A.
Partner: UNT Libraries Government Documents Department

Influence of base and PAG on deprotection blur in EUV photoresists and some thoughts on shot noise

Description: A contact-hole deprotection blur metric has been used to monitor the deprotection blur of an experimental open platform resist (EH27) as the weight percent of base and photo acid generator (PAG) were varied. A 6x increase in base weight percent is shown to reduce the size of successfully patterned 1:1 line-space features from 52 nm to 39 nm without changing deprotection blur. Corresponding isolated line-edge-roughness is reduced from 6.9 nm to 4.1 nm. A 2x increase in PAG weight percent is shown to improve 1:1 line-space patterning from 47 nm to 40 nm without changing deprotection blur or isolated LER. A discussion of improved patterning performance as related to shot noise and deprotection blur concludes with a speculation that the spatial distribution of PAG molecules has been playing some role, perhaps a dominant one, in determining the uniformity of photo generated acids in the resists that have been studied.
Date: June 1, 2008
Creator: Anderson, Christopher N.; Naulleau, Patrick P.; Niakoula, Dimitra; Hassanein, Elsayed; Brainard, Robert; Gallatin, Gregg et al.
Partner: UNT Libraries Government Documents Department

A General Analysis of Thin Wire Pickups for High Frequency Beam Position Monitors

Description: In many particle accelerators, a large number of high frequency beam position monitors (BPMs) are required to track and correct the orbit of the beam. Therefore, simple, sensitive, low cost pickup designs for such BPMs are of widespread interest. In this paper, a general analysis of arbitrarily terminated thin wire stripline or
Date: October 1, 1990
Creator: Barry, Walter
Partner: UNT Libraries Government Documents Department


Description: The longitudinal bunch profile acquisition system at RHIC was recently upgraded to allow on-line measurements of the bunch spectrum, and collision vertex location and shape. The system allows monitoring the evolution of these properties along the ramp, at transition and rebucketing, and at store conditions. We describe some of the hardware and software changes, and show some applications of the system.
Date: July 5, 2004
Creator: VAN ZEIJTS,J.
Partner: UNT Libraries Government Documents Department

Sequential Model-Based Detection in a Shallow Ocean Acoustic Environment

Description: A model-based detection scheme is developed to passively monitor an ocean acoustic environment along with its associated variations. The technique employs an embedded model-based processor and a reference model in a sequential likelihood detection scheme. The monitor is therefore called a sequential reference detector. The underlying theory for the design is developed and discussed in detail.
Date: March 26, 2002
Creator: Candy, J V
Partner: UNT Libraries Government Documents Department

Bench test of a residual gas ionization profile monitor (RGIPM)

Description: An RGIPM has been designed1, constructed and bench tested to verify that all components are functioning properly and that the desired resolution of about 50 {micro}m rms can be achieved. This paper will describe major considerations that went into the bench test and some results.
Date: January 1, 2001
Creator: Sellyey, W. C. (William C.); Gilpatrick, J. D. (John Douglas) & Senior, R. (Ralph)
Partner: UNT Libraries Government Documents Department

Results of Vapor Space Monitoring of Flammable Gas Watch List Tanks

Description: This report documents the measurement of headspace gas concentrations and monitoring results from the Hanford tanks that have continuous flammable gas monitoring. The systems used to monitor the tanks are Standard Hydrogen Monitoring Systems. Further characterization of the tank off-gases was done with Gas Characterization systems and vapor grab samples. The background concentrations of all tanks are below the action level of 6250 ppm. Other information which can be derived from the measurements (such as generation rate, released rate, and ventilation rate) is also discussed.
Date: September 27, 2000
Creator: McCain, D. J.
Partner: UNT Libraries Government Documents Department

Performance testing of Eberline Alpha 6 and Alpha 6A continuous air monitors

Description: Eberline Alpha 6 and Alpha 6A continuous air monitors (CAMs) were tested against the performance criteria of the International Electrotechnical Commission standard 761-6, ``Equipment for Continuously Monitoring Radioactivity in Gaseous Effluents, Part 6: Specific Requirements for Transuranic Aerosol Effluent Monitors``, and against ANSI N42.17B, ``Performance Specification Health Physics Instrumentation--Occupational Airborne Radioactivity Monitoring Instrumentation``. The performance criteria require the CAM`s response to a radioactive source to remain within a tolerance while the CAM is exposed to an external influence such as temperature, electromagnetic fields, or ionizing radiations. The CAMs complied within specified tolerances with a majority of the performance specifications. The most significant problems with CAM performance were noted during exposures to external nonionizing radiation fields (radio frequency fields). At numerous frequencies, the CAMs did not respond to radioactive material in the filter holder. At other frequencies and in some orientations, the CAMs overresponded by orders of magnitude. In addition to sensitivity to external nonionizing radiation fields, the CAMs exhibited sensitivity to electrostatic discharges.
Date: January 1, 1998
Creator: Johnson, M.L.
Partner: UNT Libraries Government Documents Department


Description: It is well known that beam position monitors (BPM) utilizing signals from pickup electrodes (PUE) provide good resolution and relative accuracy. The absolute accuracy (i.e. position of the orbit in the vacuum chamber) is not very good due to the various reasons. To overcome the limitation it was suggested to use magnetic centers of quadrupoles for the calibration of the BPM [1]. The proposed method provides accuracy better then 200 microns for centering of the beam position monitors using modulation of the whole quadrupole family.
Date: November 1, 2005
Creator: PINAYEV, I.
Partner: UNT Libraries Government Documents Department


Description: Ion chambers are in common use as beam loss monitors at many accelerators. A unit designed and used at FNAL and later at BNL was proposed for the SNS. Concerns about the ion collection times and low collection efficiency at high loss rates led to improvements to this unit and the design of an alternate chamber with better characteristics. Prototypes have been tested with pulsed beams. The design and test results for both detectors will be presented.
Date: May 6, 2002
Partner: UNT Libraries Government Documents Department

A prototype ionization profile monitor for RHIC

Description: Transverse beam profiles in the Relativistic Heavy-Ion Collider (RHIC) will be measured with ionization profile monitors (IPM`s). Each IPM collects and measures the distribution of electrons in the beamline resulting from residual gas ionization during bunch passage. The electrons are swept transversely from the beamline and collected on strip anodes oriented parallel to the beam axis. At each bunch passage the charge pulses are amplified, integrated, and digitized for display as a profile histogram. A prototype detector was tested in the injection line during the RHIC Sextant Test. This paper describes the detector and gives results from the beam tests.
Date: July 1, 1997
Creator: Connolly, R.; Cameron, P. & Ryan, W.
Partner: UNT Libraries Government Documents Department

Work plan for the developmental control of portable SHMS-E+platform

Description: This document describes the Developmental Control process to be used by Dyncorp Fabrication Services and SGN Eurisys Services Corporation - Remote Sensing and Sampling Equipment Engineering (RSSE) in the fabrication of two portable SHMS- E+ Platforms for Lockheed Martin Hanford (TWRS).
Date: June 16, 1997
Creator: Philipp, B.L.
Partner: UNT Libraries Government Documents Department

An Optimized International Vehicle Monitor

Description: This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goal of this project was to evaluate detector configurations to achieve a vehicle monitor that is economical, practical to install, and has adequate sensitivity to be an effective barrier to illegal transportation of special nuclear materials. We designed a new detector configuration that improves the sensitivity of available drive-through vehicle monitors by more than a factor of 5 while not changing the nuisance alarm rate.
Date: July 16, 1999
Creator: York, R.L.; Close, D.A. & Fehlau, P.E.
Partner: UNT Libraries Government Documents Department

Observation of the spread of the readings in the Linac toroids and BPMs

Description: The readback accuracy on the high-energy toroids is about 0.26 mA. This does not consider, completely, the relative offsets among the toroids, just the accuracy of one reading on one toroid. Similarly, if you remove the way in which the beam moves in the beam pipe and ignore the relative offsets of the BPMs themselves, then the absolute accuracy of the reading on a BPM is 35 microns.
Date: November 9, 2001
Creator: McCrory, Elliott S
Partner: UNT Libraries Government Documents Department