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Real-Time Measurement of Rates of Outdoor Airflow into HVACSystems: A Field Study of Three Technologies

Description: Technologies for real-time continuous measurement of the flow rates of outdoor air (OA) into HVAC systems are now available commercially. Our prior papers reported on laboratory-based evaluations of these measurement technologies and this document describes the methods and results of a field study of the accuracy of three of these technologies. From the field study data, we determined that neither wind speed nor wind direction have an important adverse impact on measurement accuracy. The field study confirmed that these three measurement technologies can provide reasonably accurate measurements of outdoor air intake rates in field settings, if the pressure signals are measured with high accuracy. Some of the pressure transducers marketed for use with commercial HVAC systems were determined to be sufficiently accurate for this application. Given the significant impact of OA flow rates on both energy use and occupant health, more widespread use of technologies that provide for real time measurements of OA flow rates seems warranted.
Date: September 1, 2005
Creator: Fisk, William J.; Sullivan, Douglas P. & Faulkner, David
Partner: UNT Libraries Government Documents Department

Measurement of the Rise-Time in a Single Sided Ladder Detector

Description: In this note we report on the measurement of the preamplifier output rise time for a SVXII chip mounted on a D0 single sided ladder. The measurements were performed on the ladder 001-883-L, using the laser test stand of Lab D. The rise time was measured for different values of the response (or bandwidth) of the preamplifier. As a bigger bandwidth results in longer rise times and therefore in less noise, the largest possible bandwidth consistent with the time between bunch crossings should be chosen to operate the detectors. The rise time is defined as the time elapsed between 10% and 90% of the charge is collected. It is also interesting to measure the time for full charge collection and the percentage of charge collected in 132 ns and 396 ns. The results are shown in table 1, for bandwidths between 2 and 63 (binary numbers). The uncertainty on the time measurement is considered to be {approx} 10 ns. Figure 1 schematically defines the four quantities measured: rise time, time of full charge collection, and percentage of charge collected in 132 ns and 396 ns. Figures 2 to 8 are the actual measurements for bandwidths of 2, 4, 8, 12, 24, 32 and 63. Figure 9 is a second measurement for BW=24, used as a consistency check of the system and the time measurement performed on the plots. The data indicate that the single sided ladders can be operated at BW=63 for 396 ns and BW=12 for 132 ns, achieving full charge collection. This will result in smaller noise than originally anticipated.
Date: November 10, 1997
Creator: Gerber, C. E.
Partner: UNT Libraries Government Documents Department

In-Situ Real Time Measurements of Molten Glass Properties, Final Report

Description: Energy Research Company (ERCo) of Staten Island, NY has developed a sensor capable of measuring in situ and in real time, both the elemental composition and the temperature of molten glass. A prototype sensor has been designed, constructed and tested in ERCo's laboratory. The sensor was used to collect atomic emission spectra from molten fiberglass via Laser Induced Breakdown Spectroscopy (LIBS). From these spectra, we were able to readily identify all elements of interest (B, Si, Ca, Fe, Mg, Na, Sr, Al). The high signal-to-background signals achieved suggest that data from the sensor can be used to determine elemental concentrations, either through calibration curves or using ERCo's calibrationless method. ERCo's technology fits in well with DOE's Glass Industry Technology Roadmap which emphasizes the need for accurate process and feedstock sensors. Listed first under technological barriers to increased production efficiency is the 'Inability to accurately measure and control the production process'. A large-scale glass melting furnace, developed by SenCer Inc. of Penn Yan, NY was installed in ERCo's laboratory to ensure that a large enough quantity of glass could be melted and held at temperature in the presence of the water-cooled laser sensor without solidifying the glass.
Date: December 16, 2007
Creator: Saro, Robert De & Craparo, Joe
Partner: UNT Libraries Government Documents Department

Recent Advances in Millimicrosecond Counting Techniques

Description: The author describes some of the changes that are now occurring or are likely to occur quite soon in the fast counting techniques. The author draws heavily on the information and advice of Dr. Clyde Wiegand and Mr. Quentin Kerns of the University of California Radiation Laboratory. The techniques the author mentions should be quite useful in several different types of experiments. The fast conicidence techniques are principally used for reducing background from accidental coincidences, for measuring times of flight of particles from one counter to another, and for measuring the life times of unstable particles.
Date: April 17, 1956
Creator: Chamberlain, Owen
Partner: UNT Libraries Government Documents Department

Hi-Q Rotor - Low Wind Speed Technology

Description: The project objective was to optimize the performance of the Hi-Q Rotor. Early research funded by the California Energy Commission indicated the design might be advantageous over state-of-the-art turbines for collecting wind energy in low wind conditions. The Hi-Q Rotor is a new kind of rotor targeted for harvesting wind in Class 2, 3, and 4 sites, and has application in areas that are closer to cities, or 'load centers.' An advantage of the Hi-Q Rotor is that the rotor has non-conventional blade tips, producing less turbulence, and is quieter than standard wind turbine blades which is critical to the low-wind populated urban sites. Unlike state-of-the-art propeller type blades, the Hi-Q Rotor has six blades connected by end caps. In this phase of the research funded by DOE's Inventions and Innovation Program, the goal was to improve the current design by building a series of theoretical and numeric models, and composite prototypes to determine a best of class device. Development of the rotor was performed by aeronautical engineering and design firm, DARcorporation. From this investigation, an optimized design was determined and an 8-foot diameter, full-scale rotor was built and mounted using a Bergey LX-1 generator and furling system which were adapted to support the rotor. The Hi-Q Rotor was then tested side-by-side against the state-of-the-art Bergey XL-1 at the Alternative Energy Institute's Wind Test Center at West Texas State University for six weeks, and real time measurements of power generated were collected and compared. Early wind tunnel testing showed that the cut-in-speed of the Hi-Q rotor is much lower than a conventional tested HAWT enabling the Hi-Q Wind Turbine to begin collecting energy before a conventional HAWT has started spinning. Also, torque at low wind speeds for the Hi-Q Wind Turbine is higher than the tested conventional HAWT and enabled ...
Date: January 11, 2010
Creator: Mills, Todd E. & Tatum, Judy
Partner: UNT Libraries Government Documents Department

Tomographic Imaging of Upper Mantle P- and S-wave Velocity Heterogeneity Beneath the Arabian Peninsula

Description: We report the estimates of three-dimensional P- and S-wave velocity structure beneath the Arabian Peninsula estimated from travel time delay tomography. We have completed travel time measurements and inversion of a partial data set provided by King Abdulaziz City for Science and Technology (KACST). This study builds on previous work by Benoit et al. (2003) following the methods of VanDecar and Crosson (1990) and VanDecar (1991). Data were collected from the Saudi Arabian National Digital Seismic Network (SANDSN) operated by KACST. The network consists of 38 stations (27 broadband and 11 short-period). We augmented the KACST data with delay times measured from permanent Incorporated Research Institutions for Seismology (IRIS) stations in the region (RAYN, EIL and MRNI) and the 1996 Saudi Arabian PASSCAL Experiment. This study shows the inverted P- and S-wave models computed with the combined data with all three different seismic networks (KASCST, IRIS, and the 1996 Saudi Arabian PASSCAL experiment) with best coverage beneath the Arabian Shield. Tomographic images reveal low velocity features in the upper mantle along a north-south line from the southern Asir region to the northeastern portion of the Arabian Shield.
Date: August 30, 2005
Creator: Park, Y; Nyblade, A; Rodgers, A & Al-Amri, A
Partner: UNT Libraries Government Documents Department

Vogtle Electric Generating Plant ETE Analysis Review

Description: Under contract with the Nuclear Regulatory Commission (NRC), staff from Pacific Northwest National Laboratory (PNNL) and Sandia National Laboratory (SNL)-Albuquerque reviewed the evacuation time estimate (ETE) analysis dated April 2006 prepared by IEM for the Vogtle Electric Generating Plant (VEGP). The ETE analysis was reviewed for consistency with federal regulations using the NRC guidelines in Review Standard (RS)-002, Supplement 2 and Appendix 4 to NUREG-0654, and NUREG/CR-4831. Additional sources of information referenced in the analysis and used in the review included NUREG/CR-6863 and NUREG/CR-6864. The PNNL report includes general comments, data needs or clarifications, and requests for additional information (RAI) resulting from review of the ETE analysis.
Date: December 9, 2006
Creator: Diediker, Nona H. & Jones, Joe A.
Partner: UNT Libraries Government Documents Department

Surface Radiation Survey at the Shepley’s Hill Remediation Site, Devens, Massachusettes

Description: The Idaho National Laboratory (INL) provided technical support for ongoing environmental remediation activities at the Shepley’s Hill remediation site, near Devens, MA. The technical support included the completion of a radiation survey of naturally occurring radioactive materials (NORM) at Shepley’s Hill, Shepley’s Hill landfill cover, and Red Cove areas. The objective of the radiation survey was to assess the ability of the INL backpack sodium iodide spectroscopy (BaSIS) system to detect elevated levels of NORM that may be associated with radon-222 emanation from near surface and subsurface fractures in the area. It is postulated that these fracture zones provide subsurface conduits for the transport of environmental contaminants. As such, location of these fracture sets will proved EPA Region 1 with the means for completing the development of an accurate site conceptual model. The results of the radiological survey show that some of the radiological anomalies correlate with currently mapped rock outcrops; however, not all of the rock outcrops in the surveyed area have been mapped. As such, it is not conclusive that all of the radiological anomalies correspond with surface rock outcrops. EPA Region 1 intends to perform a more comprehensive correlation of the radiation data collected with the BaSIS system with additional data sets such as detailed bedrock structural mapping, 2-dimensional resistivity profiling, and high-resolution topographic mapping. The results of this effort will be used in consideration of designing a potential follow-on effort for mapping of radon.
Date: September 1, 2009
Creator: Giles, J. R.; Oertel, C. P. & Roybal, L. G.
Partner: UNT Libraries Government Documents Department

Scintillation counter and wire chamber front end modules for high energy physics experiments

Description: This document describes two front-end modules developed for the proposed MIPP upgrade (P-960) experiment at Fermilab. The scintillation counter module was developed for the Plastic Ball detector time and charge measurements. The module has eight LEMO 00 input connectors terminated with 50 ohms and accepts negative photomultiplier signals in the range 0.25...1000 pC with the maximum input voltage of 4.0 V. Each input has a passive splitter with integration and differentiation times of {approx}20 ns. The integrated portion of the signal is digitized at 26.55 MHz by Analog Devices AD9229 12-bit pipelined 4-channel ADC. The differentiated signal is discriminated for time measurement and sent to one of the four TMC304 inputs. The 4-channel TMC304 chip allows high precision time measurement of rising and falling edges with {approx}100 ps resolution and has internal digital pipeline. The ADC data is also pipelined which allows deadtime-less operation with trigger decision times of {approx}4 {micro}s. The wire chamber module was developed for MIPP EMCal detector charge measurements. The 32-channel digitizer accepts differential analog signals from four 8-channel integrating wire amplifiers. The connection between wire amplifier and digitizer is provided via 26-wire twist-n-flat cable. The wire amplifier integrates input wire current and has sensitivity of 275 mV/pC and the noise level of {approx}0.013 pC. The digitizer uses the same 12-bit AD9229 ADC chip as the scintillator counter module. The wire amplifier has a built-in test pulser with a mask register to provide testing of the individual channels. Both modules are implemented as a 6Ux220 mm VME size board with 48-pin power connector. A custom europack (VME) 21-slot crate is developed for housing these front-end modules.
Date: January 1, 2011
Creator: Baldin, Boris & DalMonte, Lou
Partner: UNT Libraries Government Documents Department

Electromagnetic exploration system. Progress report

Description: A design for a cost effective, highly flexible, and portable controlled source EM exploration system is presented. The design goals of the CMOS micro-processor based receiver and its companion transmitter are listed. (MHR)
Date: November 1, 1978
Partner: UNT Libraries Government Documents Department

SAO HMC photodetector/event timer engineering model test report

Description: The test unit is a custom photodetector/event timer, PET, built for the Smithsonian Astrophysical Observatory, SAO, by Los Alamos which records elapsed time in 10 ps steps. The 1 Kg, 12 cm diameter PET unit uses 10 watts of electrical power and was tested to SAO`s specified flight conditions. The event timer has two inputs -- a reference clock oscillator input and a stop signal. Like a stop watch with split timing capability, the event timer records the instant a stop signal arrives. At that sample instant, the number of elapsed clock cycles are stored and the sample instant position between two reference clock edges is interpolated and stored. Then that stored data can be shifted serially to an external computer. The photodetector part of the PET responds to an optical input and provides the electrical output signal to the event timer specifying the sample instant. This test report discusses the event timer test results. Test equipment is shown for most of the operational tests. The relay rack contains test pursers and clocks. The environmental chamber controls temperature. The computer reads and records the serial data from the PET. Reported testing topics include: Pulse shapes to be used as test inputs, test results obtained using the electrical source`s input, optical test results which are the best simulation of specified operational conditions, heat sink operation in vacuum. Vibration tests performed to SAO`s specification.
Date: October 5, 1994
Partner: UNT Libraries Government Documents Department

NVLAP gap analysis. Final report

Description: The capabilities of AlliedSignal Metrology were compared to the requirements contained in the National Voluntary Laboratory Accreditation Program (NVLAP) Calibration Laboratories Handbook and NVLAP Calibration Laboratories Technical Guide. The initial analyses demonstrated a need for improved measurement uncertainty analyses, additional control artifacts, and improved statistical process control. The analysis also revealed the need for a formalized customer complaint system and a calibration quality manual.
Date: April 1, 1997
Creator: Shroyer, K.A.
Partner: UNT Libraries Government Documents Department

Early-time measurements of laser-plasma conditions in omega-upgrade ICF targets. Semi-annual report, October 1, 1997--March 31, 1998

Description: Since arrival of FY-98 funding under this grant in December, we have been preparing for our first series of experiments under this grant at the University of Rochester Laboratory for Laser Energetics (LLE) on the Omega laser facility, now scheduled the week beginning May 4, 1998. We will again be fielding our flat-field, grazing-incidence extreme-ultraviolet (euv) spectrograph with a four-channel gated-stripline microchannel plate (MCP) detector, which is mounted on the outside of the vacuum chamber approximately 60 inches from the center. In addition, we will be using for the first time our newly constructed flat field spectrograph covering the spectral range of 30-250 {angstrom} (hv = 50-400 eV), designed to fit into a Ten Inch Manipulator (TIM). As such, it can be located closer to the central target position, with an expected enhancement in sensitivity of at least a factor-of-ten. It is the preparation of this instrument that mainly has occupied our attention so far in this grant period and discussed in this report.
Date: April 4, 1998
Creator: Griem, H.R. & Elton, R.C.
Partner: UNT Libraries Government Documents Department

Early-time measurements of laser-plasma conditions in OMEGA-Upgrade ICF Targets. Final report, April 1, 1997--March 31, 1998

Description: Under this FY-97 NLUF grant, we primarily carried out spectral line and continuum diagnostics at early times and in the coronal region of the plasma using our flat-field grazing-incidence spectrograph, improved to incorporate time resolution at wavelengths extending below the carbon K-absorption edge using a gated microchannel plate detector. These experiments were carried out on the OMEGA facility. Fifty-nine beams were focused onto the target, providing nominally 18 kJ of energy in a 1 ns pulse for an irradiance of {approximately}2{times}10{sup 14}/cm{sup 2}. Some beam smoothing, provided by spectral dispersion, was used, but may not have been particularly effective alone, i.e., without the presence of distributed phase plates in the beams. The plastic microballoon targets were nominally 900 {mu}m in diameter with 10- and 20-{mu}m thick walls, and were filled with neon to a pressure of 10 atm. Overcoatings of Mg and Al in thicknesses ranging from 0.2 to 4 {mu}m were applied. A 1-{mu}m thick layer of CH was added in some early shots to reduce the rate of expansion of the metallic coatings. In the extreme ultraviolet (euv) spectral region, we observed n=3 to n=2 emissions from Li-, He- and H-like ions from the Mg and Al coatings. We also obtained evidence confirming our previously-published laser-field-induced satellites lines at 53.1 {Angstrom} and 62.8 {Angstrom}, apparently at the peak of the Gaussian drive pulse. Both the Mg-line and the continuum euv emissions are high during the radial collapse. The metallic coating materials appear to be in place to some degree during the compression phase, i.e., are not all blown away as coronal plasma at earlier times as modeled. This also is apparent in the Al Lyman-{alpha} x-ray measurements before and after compression. Here, however, higher line opacity made it difficult to track the resonance lines through the compression phase. ...
Date: April 4, 1998
Creator: Griem, H.R. & Elton, R.C.
Partner: UNT Libraries Government Documents Department

Early-time measurements of soft x-ray emission in an omega-upgrade laser-produced plasma. Semi-annual report, October 1, 1996--March 31, 1997

Description: Beginning in January 1997 (following arrival of the FY-97 funding) we have been preparing for our first series of experiments under this grant at the University of Rochester Laboratory for Laser Energetics (LLE) on the Omega Upgrade laser facility, now scheduled to commence June 2, 1997. For these experiments we have purchased (just arrived) a four-channel gated-stripline microchannel plate (MCP) detector to be coupled to our soft x-ray flat-field grazing incidence spectrograph used previously at LLE. This will permit time-resolved `snapshots` of the complete spectra with a resolution to times as short as 180 ps per strip. An advantage of this technique over the streak camera used previously is the lack of any carbon absorbers such as in the thin plastic cathode required for the streak camera. This eliminates absorption in the 30-44 {angstrom} spectral region in which we are interested for intermediate-Z target materials such as Mg, Al and Si. An auxiliary turbomolecular-drag pump has also been installed in order to obtain the necessary vacuum for optimum MCP operation.
Date: March 31, 1997
Creator: Griem, H.R.; Elton, R.C. & Welch, B.L.
Partner: UNT Libraries Government Documents Department

Strong motion duration and earthquake magnitude relationships

Description: Earthquake duration is the total time of ground shaking from the arrival of seismic waves until the return to ambient conditions. Much of this time is at relatively low shaking levels which have little effect on seismic structural response and on earthquake damage potential. As a result, a parameter termed ``strong motion duration`` has been defined by a number of investigators to be used for the purpose of evaluating seismic response and assessing the potential for structural damage due to earthquakes. This report presents methods for determining strong motion duration and a time history envelope function appropriate for various evaluation purposes, for earthquake magnitude and distance, and for site soil properties. There are numerous definitions of strong motion duration. For most of these definitions, empirical studies have been completed which relate duration to earthquake magnitude and distance and to site soil properties. Each of these definitions recognizes that only the portion of an earthquake record which has sufficiently high acceleration amplitude, energy content, or some other parameters significantly affects seismic response. Studies have been performed which indicate that the portion of an earthquake record in which the power (average rate of energy input) is maximum correlates most closely with potential damage to stiff nuclear power plant structures. Hence, this report will concentrate on energy based strong motion duration definitions.
Date: June 1, 1992
Creator: Salmon, M.W.; Short, S.A. & Kennedy, R.P.
Partner: UNT Libraries Government Documents Department

A method for calculating longitudinal phase space distribution when given the time profile of the bunch

Description: We will show in this paper a method for calculating the longitudinal phase space distribution when the time profile of the bunch as measured by a wall current monitor is given. The key to this method is the assumption that the bunch is matched to the bucket. With this assumption, we will show that the method boils down to solving a simple upper triangular matrix equation. We will also illustrate the method with two examples and show the method's shortcomings.
Date: July 30, 2001
Creator: Tan, Cheng-Yang
Partner: UNT Libraries Government Documents Department

One dimensional time-to-explode (ODTX) in HMX spheres

Description: In a series of papers researchers at Lawrence Livermore National Laboratory (LLNL) have reported measurements of the time to explosion in spheres of various high explosives following a rapid, uniform increase in the surface temperature of the sphere. Due to the spherical symmetry, the time-dependent properties of the explosive (temperature, chemical composition, etc.) are functions of the radial spatial coordinate only; thus the name one-dimensional time-to-explosion (ODTX). The LLNL researchers also report an evolving series of computational modeling results for the ODTX experiments, culminating in those obtained using a sophisticated heat transfer code incorporating accurate descriptions of chemical reaction. Although the chemical reaction mechanism used to describe HMX decomposition is quite simple, the computational results agree very well with the experimental data. In addition to reproducing the magnitude and temperature dependence of the measured times to explosion, the computational results also agree with the results of post reaction visual inspection. The ODTX experiments offer a near-ideal example of a transport process (heat transfer in this case) tightly coupled with chemical reaction. The LLNL computational model clearly captures the important features of the ODTX experiments. An obvious question of interest is to what extent the model and/or its individual components (specifically the chemical reaction mechanism) are applicable to other experimental scenarios. Valid exploration of this question requires accurate understanding of (1) the experimental scenario addressed by the LLNL model and (2) details of the application of the model. The author reports here recent work addressing points (1) and (2).
Date: June 2, 1997
Creator: Breshears, D.
Partner: UNT Libraries Government Documents Department

Implementation of detonation electric effects. [Quarterly report], January--March 1971

Description: Detonation electric effect measurement was applied to a stack of PMMA discs on the output of an explosive PWL to resolve some anomalies previously observed in the arrival times of a shock wave as it passes through the various interfaces. A brief description of the experiments and some comments on the results are included.
Date: December 31, 1971
Creator: Boettner, J.K.
Partner: UNT Libraries Government Documents Department

Development of inexpensive continuous emission monitors for feedback control of combustion devices that minimize greenhouse gases, toxic emissions, and ozone damaging products

Description: This is the final report of a three-year, Laboratory Directed Research and Development project at the Los Alamos National Laboratory. Combustion is the major cause of poor urban air quality, of depletion of the ozone layer, and a major source of the greenhouse gas, carbon dioxide. Careful control of combustor conditions is important for minimizing the effects of combustion on the environment. The authors have developed sensitive, inexpensive continuous emission monitors that will assist in direct feedback of turbine power systems and provide assurance to the public and the operators of the facilities that their facility emissions lie within the accepted bounds. These include a robust solid-state Fourier transform spectrometer for rapid gas analysis, based on the use of ferroelectric liquid crystal technology, and an infrared helium-neon probe for real time measurement of combustor air-to-fuel ratios.
Date: November 1, 1998
Creator: Funk, D.J.; Moore, D.S.; Mongia, R.K.; Tomita, E.; Hsu, F.K.; Talbot, L. et al.
Partner: UNT Libraries Government Documents Department

Soviet precision timekeeping research and technology

Description: This report is the result of a study of Soviet progress in precision timekeeping research and timekeeping capability during the last two decades. The study was conducted by a panel of seven US scientists who have expertise in timekeeping, frequency control, time dissemination, and the direct applications of these disciplines to scientific investigation. The following topics are addressed in this report: generation of time by atomic clocks at the present level of their technology, new and emerging technologies related to atomic clocks, time and frequency transfer technology, statistical processes involving metrological applications of time and frequency, applications of precise time and frequency to scientific investigations, supporting timekeeping technology, and a comparison of Soviet research efforts with those of the United States and the West. The number of Soviet professionals working in this field is roughly 10 times that in the United States. The Soviet Union has facilities for large-scale production of frequency standards and has concentrated its efforts on developing and producing rubidium gas cell devices (relatively compact, low-cost frequency standards of modest accuracy and stability) and atomic hydrogen masers (relatively large, high-cost standards of modest accuracy and high stability). 203 refs., 45 figs., 9 tabs.
Date: August 1, 1991
Creator: Vessot, R.F.C.; Allan, D.W.; Crampton, S.J.B.; Cutler, L.S.; Kern, R.H.; McCoubrey, A.O. et al.
Partner: UNT Libraries Government Documents Department

Summary of activity. Topic I: detectors and experiments. [High-energy detectors for use at ISABELLE]

Description: Results of a workshop studying detectors for Isabelle experimental halls are described. The detectors must be very reliable. Spatial resolution of the tracking detectors must be high to provide accurate measurements of angle and momentum, retain a short resolving time, and show excellent multiparticle handling capability. Included in the study were hodoscopes, drift chambers, proportional chambers, time projection chambers, Cherenkov counters, electromagnetic shower detectors, and hadron calorimeters. Data handling methods were also included in the studies. (FS)
Date: unknown
Creator: Marx, J. & Ozaki, S.
Partner: UNT Libraries Government Documents Department