These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Analysis of the single-blow transient testing technique for perforated plate heat exchangers  

NASA Technical Reports Server (NTRS)

An analysis of the single-blow transient testing technique for heat exchanger surfaces is made for perforated plate and similar discontinuous surfaces. The model assumes that there is no temperature variation across each plate, and allows for axial conduction in spacers: the resulting axial fluid temperature profile is discontinuous, rather than the usual continuous profile. Numerical solutions are obtained to the resulting set of coupled first-order differential equations for a step change in inlet fluid temperature. Results are presented in tabular form, which allow the heat transfer coefficients to be calculated from test data using the maximum slope technique.

Rodriguez, Jose I.; Mills, Anthony F.

1990-01-01

2

Permeability-porosity relationship for compaction of a low-permeability creeping material : Experimental evaluation using a single transient test  

NASA Astrophysics Data System (ADS)

It is well-known that there is no unique permeability-porosity relationship that can be applied to all porous materials. For a given evolution process that changes both permeability and porosity of a porous material, for example elastic or plastic compaction, microcracking or chemical alteration, it is usually assumed that there is an empirical relationship in the form of a power-law or exponential relationship between these parameters. The coefficients of these empirical relationships depend strongly on the properties of the material and of the evolution process. For the case of the power-law permeability-porosity relationship, a review of the literature shows that the exponent of this relation may be integer or non-integer, constant or variable, and the reported values of exponent vary between 1.1 and 25.4 for different materials and evolution processes, but no clear correlation between the exponenet and the petrophysical properties could be found. This wide variability of the permeability-porosity relationship highlights the necessity of experimental evaluation of this relationship for each material and evolution process. An experimental method is presented for the evaluation of a permeability-porosity relationship in a low-permeability porous material using the results of a single transient test. This method accounts for both elastic and non-elastic deformations of the sample during the test and is applied to a hardened class G oil well cement paste. An initial hydrostatic undrained loading is applied to the sample which generates an excess pore pressure, related to the applied hydrostatic stress by the Skempton coefficient of the material. The generated excess pore pressure is then released at one end of the sample while monitoring the pore pressure at the other end and the radial strain in the middle of the sample during the dissipation of the pore pressure. These measurements are back analysed using a finite-difference numerical scheme to evaluate the permeability and its evolution with porosity change. The stress-dependent character of the poroelastic parameters of the hardened cement paste (Ghabezloo et al., 2008) and also the creep of the material during the test add some particular aspects to the back-analysis, which makes this problem different from the classical solutions of transient permeability evaluation tests. The effect of creep of the sample during the test on the measured pore pressure and volume change is taken into account in the analysis. This approach permits to calibrate a power law permeability-porosity relationship for the tested hardened cement paste and also two parameters of a viscoelastic model for the creep of the material. The porosity sensitivity exponent of the power-law is evaluated equal to 11 and is shown to be mostly independent of the stress level and of the creep strains. The proposed method can be applied to different low permeability porous materials and for the case of non-creeping materials, the same type of analysis can be used to calibrate either a permeability-porosity or a permeability-effective stress relationship for the compaction of the tested material using a single transient test. References: 1.Ghabezloo S., Sulem J., Saint-Marc, J. (2008) Evaluation of a permeability-porosity relationship in a low permeability creeping material using a single transient test. Int J Rock Mech Min Sci, in press, DOI 10.1016/j.ijrmms.2008.10.003. 2.Ghabezloo, S., Sulem, J., Guédon, S., Martineau, F., Saint-Marc, J. (2008) Poromechanical behaviour of hardened cement paste under isotropic loading. Cement and Concrete Research, 38(12), 1424-1437.

Ghabezloo, S.; Sulem, J.; Saint-Marc, J.

2009-04-01

3

Single-Event Transient Testing of Low Dropout PNP Series Linear Voltage Regulators  

NASA Technical Reports Server (NTRS)

As demand for high-speed, on-board, digital-processing integrated circuits on spacecraft increases (field-programmable gate arrays and digital signal processors in particular), the need for the next generation point-of-load (POL) regulator becomes a prominent design issue. Shrinking process nodes have resulted in core rails dropping to values close to 1.0 V, drastically reducing margin to standard switching converters or regulators that power digital ICs. The goal of this task is to perform SET characterization of several commercial POL converters, and provide a discussion of the impact of these results to state-of-the-art digital processing IC through laser and heavy ion testing

Adell, Philippe; Allen, Gregory

2013-01-01

4

Single Event Transients in Low Voltage Dropout (LVDO) Voltage Regulators  

NASA Technical Reports Server (NTRS)

This viewgraph presentation reviews the use of Low Voltage Dropout (LVDO) Voltage Regulators in environments where heavy ion induced Single Event Transients are a concern to the designers.Included in the presentation are results of tests of voltage regulators.

LaBel, K.; Karsh, J.; Pursley, S.; Kleyner, I.; Katz, R.; Poivey, C.; Kim, H.; Seidleck, C.

2006-01-01

5

Columbia University flow instability experimental program: Volume 12. Single annulus transient test program data tables: Part 1  

SciTech Connect

The single annulus test program was designed to investigate the onset of flow instability in an annular geometry similar to the fuel assemblies used in the Savannah River Site production reactors. Data files were transmitted from Columbia University to Savannah River Site in a DOS compatible format. This report provides a hardcopy version of the electronic media data files.

Coutts, D.A.

1993-09-01

6

Single-Event Transients in Voltage Regulators  

NASA Technical Reports Server (NTRS)

Single-event transients are investigated for two voltage regulator circuits that are widely used in space. A circuit-level model is developed that can be used to determine how transients are affected by different circuit application conditions. Internal protection circuits-which are affected by load as well as internal thermal effects-can also be triggered from heavy ions, causing dropouts or shutdown ranging from milliseconds to seconds. Although conventional output transients can be reduced by adding load capacitance, that approach is ineffective for dropouts from protection circuitry.

Johnston, Allan H.; Miyahira, Tetsuo F.; Irom, F.; Laird, Jamie S.

2006-01-01

7

Transient Pressure Test Article Test Program  

NASA Technical Reports Server (NTRS)

The Transient Pressure Test Article (TPTA) test program is being conducted at a new test facility located in the East Test Area at the National Aeronautics and Space Administration's (NASA's) Marshall Space Flight Center (MSFC) in Huntsville, Alabama. This facility, along with the special test equipment (STE) required for facility support, was constructed specifically to test and verify the sealing capability of the Redesigned Solid Rocket Motor (RSRM) field, igniter, and nozzle joints. The test article consists of full scale RSRM hardware loaded with inert propellant and assembled in a short stack configuration. The TPTA is pressurized by igniting a propellant cartridge capable of inducing a pressure rise rate which stimulates the ignition transient that occurs during launch. Dynamic loads are applied during the pressure cycle to simulate external tank attach (ETA) strut loads present on the ETA ring. Sealing ability of the redesigned joints is evaluated under joint movement conditions produced by these combined loads since joint sealing ability depends on seal resilience velocity being greater than gap opening velocity. Also, maximum flight dynamic loads are applied to the test article which is either pressurized to 600 psia using gaseous nitrogen (GN2) or applied to the test article as the pressure decays inside the test article on the down cycle after the ignition transient cycle. This new test facility is examined with respect to its capabilities. In addition, both the topic of test effectiveness versus space vehicle flight performance and new aerospace test techniques, as well as a comparison between the old SRM design and the RSRM are presented.

Vibbart, Charles M.

1989-01-01

8

Thermophysical property testing using transient techniques  

NASA Astrophysics Data System (ADS)

Transient techniques were applied to the study of energetic materials (AP, HMX, RDX and HTPB) used in solid rocket fuel to carbon/carbon materials used as rocket nozzles. Studies on AP included single crystals, pressed powders and AP/HTPB mixtures. It was found that the conductivity of AP can be considered isotropic, even the orthrohombic phase. The conductivity values for pure AP calculated from the AP/HTPB mixtures were somewhat larger than those measured directly on single crystals due to imperfections in the relatively large single crystals. Conductivity values for Beta HMX obtained on pressed powders are believed to be 20% below those that would be obtained on good single crystals if they were available. Delta phase values are believed representative. Conductivity data useful for modeling AP/binder and HMX/binder fuel from RT to combustion were obtained. Successful techniques for determining in-situ conductivity values for carbon fibers and matrix in c/c composites were developed. The relative roles of the fibers and matrix in c/c subject to transient heat fluxes were delineated. The advantages of off-axis testing were revealed. Diffusivity values corresponding to thermal conductivity results could be obtained. The presence of a surface layer in which interconstituent thermal gradients are important and beyond which they are negligible was demonstrated.

Taylor, R. E.; Shoemaker, R. L.; Stark, J. A.; Koshigoe, L. G.

1984-06-01

9

Transient Sub-Poissonian Distribution for Single-Mode Lasers  

NASA Technical Reports Server (NTRS)

In this paper, the transient photon statistics for single-mode lasers is investigated by making use of the theory of quantum electrodynamics. By taking into account of the transitive time l,we obtain the master equation for Jaynes-Cummings model. The relation between the Mandel factor and the time is obtained by directly solving the master equation. The result shows that a transient phenomenon from the transient super-Poissonian distribution to the transient sub-Poissonian distribution occurs for single-mode lasers. In addition, the influences of the thermal light field and the cavity loss on the transient sub-Poissonian distribution are also studied.

Zang, J. Y.; Gu, Q.; Tian, L. K.

1996-01-01

10

Tension Transients in Single Isolated Smooth Muscle Cells  

NASA Astrophysics Data System (ADS)

Tension transients were recorded in a single smooth muscle cell. The transient contains a linear elastic response and a biphasic recovery that appear to originate from the cross-bridges. A comparison of transients in smooth and fast skeletal muscle fibers suggests that the cross-bridge in smooth muscle is more compliant than the cross-bridge in striated muscle and that transitions between several cross-bridge states occur more slowly in smooth muscle than in striated muscle.

Warshaw, David M.; Fay, Fredric S.

1983-03-01

11

Transient tests on an MHD thruster  

SciTech Connect

Three different types of transient tests were made -- coast downs to zero voltage and current under open circuit and short circuit conditions, reverses where the applied voltage was reversed to the same or a different value, and jumps where the voltage applied to the thruster was increased without a change in polarity. Most except the coast downs were dons both quickly (voltage changes as fast as possible) and slowly (6 s to complete the voltage change). A few slower (12 s) transients were done. Transient runs were made for water conductivities of 16.2 and 5.09 S/m. In all cases steady-state conditions were established and several seconds of data taken before initiating the transients. Data were measured every 0.75 to 1 .5 second over the time interval of interest. Particular attention was paid to looking for evidence of gas bubbles, and to the chance of the voltage profiles between the electrodes. The data are interpreted based on the behavior of the power supply and the thruster.

Pierson, E.S. (Purdue Univ., Hammond, IN (United States). Dept. of Engineering); Libera, J.; Petrick, M. (Argonne National Lab., IL (United States). Energy Systems Div.)

1993-01-01

12

Future Transient Testing of Advanced Fuels  

SciTech Connect

The transient in-reactor fuels testing workshop was held on May 4–5, 2009 at Idaho National Laboratory. The purpose of this meeting was to provide a forum where technical experts in transient testing of nuclear fuels could meet directly with technical instrumentation experts and nuclear fuel modeling and simulation experts to discuss needed advancements in transient testing to support a basic understanding of nuclear fuel behavior under off-normal conditions. The workshop was attended by representatives from Commissariat à l'Énergie Atomique CEA, Japanese Atomic Energy Agency (JAEA), Department of Energy (DOE), AREVA, General Electric – Global Nuclear Fuels (GE-GNF), Westinghouse, Electric Power Research Institute (EPRI), universities, and several DOE national laboratories. Transient testing of fuels and materials generates information required for advanced fuels in future nuclear power plants. Future nuclear power plants will rely heavily on advanced computer modeling and simulation that describes fuel behavior under off-normal conditions. TREAT is an ideal facility for this testing because of its flexibility, proven operation and material condition. The opportunity exists to develop advanced instrumentation and data collection that can support modeling and simulation needs much better than was possible in the past. In order to take advantage of these opportunities, test programs must be carefully designed to yield basic information to support modeling before conducting integral performance tests. An early start of TREAT and operation at low power would provide significant dividends in training, development of instrumentation, and checkout of reactor systems. Early start of TREAT (2015) is needed to support the requirements of potential users of TREAT and include the testing of full length fuel irradiated in the FFTF reactor. The capabilities provided by TREAT are needed for the development of nuclear power and the following benefits will be realized by the refurbishment and restart of TREAT. •TREAT is an absolute necessity in the suite of reactor fuel test capabilities •TREAT yields valuable information on reactivity effects, margins to failure, fuel dispersal, and failure propagation •Most importantly, interpretation of TREAT experiment results is a stringent test of the integrated understanding of fuel performance.

Jon Carmack

2009-09-01

13

Transient Grating Measurements of Excitonic Dynamics in Single-Walled  

E-print Network

. Because of their small diameter (1 nm) and extended dimension along the tube axis, single-walled carbon nano- tubes (SWNTs) are characterized as quasi-one-dimensional charge carriers,1 with very lowTransient Grating Measurements of Excitonic Dynamics in Single-Walled Carbon Nanotubes: The Dark

Apkarian, V. Ara

14

Transient yielding in strain rate change tests  

SciTech Connect

Strain rate change (SRC) tests, during a tensile test, are carried out frequently to determine values of activation area and proper interpretation of these results may provide considerable information on dislocation activities during deformation. However, transient load drop is generally observed during low to high SRC and this drop increases with increasing deformation. This effect may thus be exacerbated, at least in principle, by conducting SRC tests on pre-crept samples. In the present work the authors report these results and also discuss the nature of transients during low to high SRC with reference to overall deformation processes. The material used for this work was a modified 9Cr-1Mo steel containing niobium and vanadium. All SRC tests were carried out at room temperature on an Instron by instantaneously changing the cross-head speed by a factor of 10. Strain gauges were used to not only continuously monitor the overall strain but also to obtain the magnitude of strain accompanying the change in cross head speed.

Dwivedi, V.S.; Mishra, N.S.; Sen, S.K.; Jha, B.K. [Research and Development Center for Iron and Steel, Ranchi (India)] [Research and Development Center for Iron and Steel, Ranchi (India)

1997-06-15

15

Chemically resolved transient collision events of single electrocatalytic nanoparticles.  

PubMed

Here we report the use of fast-scan cyclic voltammetry (FSCV) to study transient collision and immobilization events of single electrocatalytic metal nanoparticles (NPs) on an inert electrode. In this study, a fast, repetitive voltage signal is continuously scanned on an ultramicroelectrode and its faradaic signal is recorded. Electrocatalytically active metal NPs are allowed to collide and immobilize on the electrode resulting in the direct recording of the transient voltammetric response of single NPs. This approach enables one to obtain the transient voltammetric response and electrocatalytic effects of single catalytic NPs as they interact with an inert electrode. The use of FSCV has enabled us to obtain chemical information, which is otherwise difficult to study with previous amperometric methods. PMID:24909547

Guo, Zhihui; Percival, Stephen J; Zhang, Bo

2014-06-25

16

Investigation of Transient Combustion Characteristics in a Single Tubular Combustor  

NASA Technical Reports Server (NTRS)

An investigation was conducted to determine the combustion response to rapid fuel-flow changes in a single tubular combustor at two simulated altitude-rotor speed conditions of 25,000 feet-70 percent rated engine speed and 50,000 feet-70 percent rated engine speed. Limiting rates of change of fuel flow (acceleration limits) were determined and the effects of certain combustion air flow variables on the transient combustion characteristics were studied with the aid of rapid-response instrumentation.

Donlon, Richard H; Mccafferty, Richard J; Straight, David M

1954-01-01

17

Transient behavior of a single-blade horizontal-axis wind turbine  

NASA Astrophysics Data System (ADS)

The transient behavior of the wind energy converter (WEC) MONOPTEROS was investigated. This converter is a 1:3 model scale test version (tower height 50 m) of a single-blade 5.4 MW horizontal-axis supercritically operating wind turbine. Aerodynamic and dynamic modelling techniques, the development of control strategies for the transition into/out of nominal performance, and simulated and measured time histories with emphasis on transient operating conditions, are presented. For the prediction of transients, which are the most problematic operating phases of the supercritical, single-blade wind turbine concept, the modeling of classical, stationary rotor aerodynamics is sufficient, but an exact description of the control system is required.

Wennekers, R.

18

First TREAT (Transient Reactor Test Facility) transient overpower tests on U-Pu-Zr fuel: M5 and M6  

Microsoft Academic Search

Transient Reactor Test Facility (TREAT) tests M5 and M6 were the first transient overpower (TOP) tests of the margin to cladding breach and prefailure elongation of metallic U-Pu-Zr ternary fuel, the reference fuel of the Integral Fast Reactor concept. Similar tests on U-Fs fueled EBR-II driver pins were previously performed and reported (1,2). Results from these earlier tests indicated a

W. R. Robinson; T. H. Bauer; A. E. Wright; E. A. Rhodes; G. S. Stanford; A. E. Klickman

1987-01-01

19

Transient Molecular Transfer During Vacuum Testing  

NASA Technical Reports Server (NTRS)

A common question in contamination budgeting involves the loss of collected volatiles during ambient I&T activity under vacuum and the resultant cross-contamination from outgassing. (1) How much of the material collected under ambient conditions evaporates under vacuum? (2) Why do pristine surfaces sometimes show increased molecular contamination after vacuum bakeout? (3) How much of the collected molecular contamination is transient (i.e. migratory) and how much is permanent? Measuring the transient deposition may be accomplished using a thermally passive QCM

Perry, Radford L.

2011-01-01

20

Multi-axis transient vibration testing of space objects: Test philosophy, test facility, and control strategy  

NASA Technical Reports Server (NTRS)

IABG has been using various servohydraulic test facilities for many years for the reproduction of service loads and environmental loads on all kinds of test objects. For more than 15 years, a multi-axis vibration test facility has been under service, originally designed for earthquake simulation but being upgraded to the demands of space testing. First tests with the DFS/STM showed good reproduction accuracy and demonstrated the feasibility of transient vibration testing of space objects on a multi-axis hydraulic shaker. An approach to structural qualification is possible by using this test philosophy. It will be outlined and its obvious advantages over the state-of-the-art single-axis test will be demonstrated by example results. The new test technique has some special requirements to the test facility exceeding those of earthquake testing. Most important is the high reproduction accuracy demanded for a sophisticated control system. The state-of-the-art approach of analog closed-loop control circuits for each actuator combined with a static decoupling network and an off-line iterative waveform control is not able to meet all the demands. Therefore, the future over-all control system is implemented as hierarchical full digital closed-loop system on a highly parallel transputer network. The innermost layer is the digital actuator controller, the second one is the MDOF-control of the table movement. The outermost layer would be the off-line iterative waveform control, which is dedicated only to deal with the interaction of test table and test object or non-linear effects. The outline of the system will be presented.

Lachenmayr, Georg

1992-01-01

21

Space Shuttle solid rocket motor testing for return to flight - Transient Pressure Test Article test program  

NASA Technical Reports Server (NTRS)

The Transient Pressure Test Article (TPTA) test program, which is being conducted at a new facility at NASA-Marshall, is described. The facility is designed to test and verify the sealing capability of the redesigned solid rocket motor's (RSRM) field, igniter, and nozzle joints. The test article consists of full-scale RSRM hardware loaded with inert propellant and assembled in a short stack configuration. The test facility is described as well as test implementation, test effectiveness, and test results.

Vibbart, Charles M.

1988-01-01

22

Transient thermal model of the continuous single-wheel thin-strip casting process  

Microsoft Academic Search

A transient heat-transfer model (STRIP1D) has been developed to simulate the single-roll continuous strip-casting process.\\u000a The model predicts temperature in the solidifying strip coupled with heat transfer in the rotating wheel, using an explicit\\u000a finite difference procedure. The model has been calibrated using strip thickness data from a test caster at ARMCO Inc. (Middletown,\\u000a OH) and verified with a range

Guowei Li; Brian G. Thomas

1996-01-01

23

Transient behavior of a single-blade horizontal-axis wind turbine  

Microsoft Academic Search

The transient behavior of the wind energy converter (WEC) MONOPTEROS was investigated. This converter is a 1:3 model scale test version (tower height 50 m) of a single-blade 5.4 MW horizontal-axis supercritically operating wind turbine. Aerodynamic and dynamic modelling techniques, the development of control strategies for the transition into\\/out of nominal performance, and simulated and measured time histories with emphasis

R. Wennekers

1984-01-01

24

Single Heartbeat Cardiac Tagging for the Evaluation of Transient Phenomena  

PubMed Central

Many cardiac abnormalities are of a transient nature, creating a beat-to-beat variation in myocardial function. This work presents the cardiac imaging technique for the measurement of regional function during transient cardiac phenomena. All information necessary for the reconstruction of a cine loop is acquired within a single heartbeat, avoiding the temporal blurring introduced by segmented imaging due to the assumption of cardiac cycle periodicity. This method incorporates a gradient-optimized, high-efficiency EPI-SSFP sequence and TSENSE parallel imaging. For acquisitions with readout resolutions of 128,160, 192, and 256 points, the technique produced images with average temporal resolution of 35, 39, 43, and 52 ms and average spatial resolutions of 2.65, 2.12, 1.77, and 1.32 mm in the readout direction, respectively, and 2.88 and 2.08 mm in the phase encode direction for acceleration rates of 3 and 4, respectively. Local apparent strains in the single slice and measurements of ventricular end-systolic and end-diastolic areas were used as quantitative measures to validate the single heartbeat technique. To demonstrate the utility of the sequence, movie loops were acquired for multiple heartbeats in non-breath-held acquisitions as well as during a Valsalva maneuver. A heartbeat-interleaved acquisition allowed for the reconstruction of nonaccelerated images from R contiguous heartbeats. Images reconstructed from such data displayed tag blurring and reduced tag persistence due to motion and interheartbeat variability. Images acquired during the Valsalva maneuver demonstrated apparent beat-to-beat variability, visible both in the images and as changing strain patterns and ventricular volumes. PMID:16265635

Herzka, Daniel A.; Derbyshire, J. Andrew; Kellman, Peter; McVeigh, Elliot R.

2007-01-01

25

Calculational model development for fibrous thermal insulation transient test procedures  

Microsoft Academic Search

A new theoretical model of transient combined radiation and conduction heat transfer in fibrous insulations has been developed and tested by comparison to experimental data obtained with the ORNL flat screen tester. This model predicts results which agree with this data to within )+-)1.2)degree)C for all of the transient test results available. Sensitivities of the model to the pertinent radiative

Thomas; J. R. Jr

1988-01-01

26

Utility of transient testing to characterize thermal interface materials  

E-print Network

This paper analyzes a transient method for the characterization of low-resistance thermal interfaces of microelectronic packages. The transient method can yield additional information about the package not available with traditional static methods at the cost of greater numerical complexity, hardware requirements, and sensitivity to noise. While the method is established for package-level thermal analysis of mounted and assembled parts, its ability to measure the relatively minor thermal impedance of thin thermal interface material (TIM) layers has not yet been fully studied. We combine the transient thermal test with displacement measurements of the bond line thickness to fully characterize the interface.

B. Smith; T. Brunschwiler; B. Michel

2008-01-07

27

Alternatives Analysis for the Resumption of Transient Testing Program  

SciTech Connect

An alternatives analysis was performed for resumption of transient testing. The analysis considered eleven alternatives – including both US international facilities. A screening process was used to identify two viable alternatives from the original eleven. In addition, the alternatives analysis includes a no action alternative as required by the National Environmental Policy Act (NEPA). The alternatives considered in this analysis included: 1. Restart the Transient Reactor Test Facility (TREAT) 2. Modify the Annular Core Research Reactor (ACRR) which includes construction of a new hot cell and installation of a new hodoscope. 3. No Action

Lee Nelson

2013-11-01

28

100 MHz fiber optic single transient gamma ray detection system  

SciTech Connect

A fiber optic system has been developed to measure single transient gamma rays. The gamma ray signature is converted to light by the Cerenkov process in a 20 cm length of radiation resistant optical fiber. The signal is transmitted over 1 km of optical fiber and detected by state-of-the-art, 175 MHz analog receivers. The receivers are based on silicon PIN detectors with transimpedance hybrid amplifiers and two stages of power amplification. The dc coupled receivers have less than 2% distortion up to 5 volts with less than 10 mV rms noise and a responsivity of 37,500 V/watt at 800 nm. A calibration system measures relative fiber to fiber transit time delays and ''system'' sensitivity. System bandwidth measurements utilized an electron linear accelerator (Linac) with a 50 ps electron pulse as the Cerenkov light source. The system will be described with supporting calibrationa and characterization data of parts of the system and the whole system.

Ogle, J.W.; Smith, R.C.; Ward, M.; Ramsey, R.; Hollabaugh, J.

1984-01-01

29

Testing a Globular Cluster Origin for Elusive Calcium-rich Gap Transients  

NASA Astrophysics Data System (ADS)

The advent of wide-field synoptic surveys has re-invigorated time domain astronomy. The six magnitude luminosity gap between novae and supernovae is now bridged with multiple classes of explosions that are rarer, fainter and faster than supernovae. Here, we discuss an emerging class of transients with the unique property of a small amount of ejecta dominated by Calcium. The members of this class are located in the middle of nowhere in intra-group/intra-cluster environments, offset by tens of kiloparsec from their putative host galaxy. No single model can yet explain all the observables of "Calcium-rich Gap" transients. The location distribution is inconsistent with stellar mass and yet, strikingly consistent with globular clusters. It has been speculated that the high stellar density in globulars leads to peculiar transients. Thus, we propose to use 4 HST orbits to test a globular cluster origin for these elusive Calcium-rich transients.

Kasliwal, Mansi

2014-10-01

30

Recording and time expansion technique for high-speed, single-shot transient video signal  

NASA Technical Reports Server (NTRS)

High-speed, single-shot, transient voltage is recorded on a video tape recorder, which, when played back, converts the single signal to a repetitive signal. This drives a sample data translator which lengthens the original transient production time, suiting it to an x-y plotter or computer tape recorder use.

Hruby, R. J.; Sander, R. C.

1967-01-01

31

SINGLE HEATER TEST FINAL REPORT  

SciTech Connect

The Single Heater Test is the first of the in-situ thermal tests conducted by the U.S. Department of Energy as part of its program of characterizing Yucca Mountain in Nevada as the potential site for a proposed deep geologic repository for the disposal of spent nuclear fuel and high-level nuclear waste. The Site Characterization Plan (DOE 1988) contained an extensive plan of in-situ thermal tests aimed at understanding specific aspects of the response of the local rock-mass around the potential repository to the heat from the radioactive decay of the emplaced waste. With the refocusing of the Site Characterization Plan by the ''Civilian Radioactive Waste Management Program Plan'' (DOE 1994), a consolidated thermal testing program emerged by 1995 as documented in the reports ''In-Situ Thermal Testing Program Strategy'' (DOE 1995) and ''Updated In-Situ Thermal Testing Program Strategy'' (CRWMS M&O 1997a). The concept of the Single Heater Test took shape in the summer of 1995 and detailed planning and design of the test started with the beginning fiscal year 1996. The overall objective of the Single Heater Test was to gain an understanding of the coupled thermal, mechanical, hydrological, and chemical processes that are anticipated to occur in the local rock-mass in the potential repository as a result of heat from radioactive decay of the emplaced waste. This included making a priori predictions of the test results using existing models and subsequently refining or modifying the models, on the basis of comparative and interpretive analyses of the measurements and predictions. A second, no less important, objective was to try out, in a full-scale field setting, the various instruments and equipment to be employed in the future on a much larger, more complex, thermal test of longer duration, such as the Drift Scale Test. This ''shake down'' or trial aspect of the Single Heater Test applied not just to the hardware, but also to the teamwork and cooperation between multiple organizations performing their part in the test.

J.B. Cho

1999-05-01

32

Transient response characteristics of test chamber Mach number  

NASA Technical Reports Server (NTRS)

The transient dynamic characteristics of a test chamber Mach number was established for a disturbance initiated in the test chamber. An approximate linear expression was given, showing that the change in the Mach number is linearly proportional to the algebraic sum of the static pressure change in the test chamber and the stagnation pressure change. The static pressure change is the dominating factor. The two pressure changes were also calculated for small Mach number variations, and these results were applied to instrumentation requirements.

Tcheng, P.

1976-01-01

33

EstimationofSkinFactorbyUsing PressureTransientTesting  

E-print Network

TestAnalysis #12;ProblemStatement GasstorageoperatorsspendtheirOpExdollarstotest theirstoragewells. InIndustry,MultiRateTests(MRT)andSingleRate Petroleum&NaturalGasEngineering InIndustry,MultiRateTests(MRT)andSingleRate Tests Stepsinvolvedinachievingtheobjectiveofthis study: Actualdataacquisition AnalyticalwelltestingAnalyticalwelltesting Numericalmodeling

Mohaghegh, Shahab

34

Transient method for testing flat-plate solar collectors  

Microsoft Academic Search

A transient test method has been developed to characterize the dynamic behavior of flat-plate solar collectors. It is based on a one-node model in which the heat capacity of the plate, the tubes and the fluid are lumped together in one node referred to the mean temperature of the working fluid. The method is simple and less time consuming. It

E. H. Amer; J. K. Nayak; G. K. Sharma

1998-01-01

35

Applying well flow adapted filtering to transient pumping tests  

NASA Astrophysics Data System (ADS)

Transient pumping tests are often used to estimate porous medium characteristics like hydraulic conductivity and storativity. The interpretation of pumping test drawdowns is based on methods which are normally developed under the assumption of homogeneous porous media. However aquifer heterogeneity strongly impacts on well flow pattern, in particular in the vicinity of the pumping well. The purpose of this work is to present a method to interpret drawdowns of transient pumping tests in heterogeneous porous media. With this method we are able to describe the effects that statistical quantities like variance and correlation length have on pumping test drawdowns. Furthermore it allows inferring on the statistical parameters of aquifer heterogeneity from drawdown data by invers estimation, which is not possible using methods for homogeneous media like Theis' solution. The method is based on a representative description of hydraulic conductivity for radial flow regimes. It is derived from a well flow adapted filtering procedure (Coarse Graining), where the heterogeneity of hydraulic conductivity is assumed to be log-normal distributed with a Gaussian correlation structure. applying the up scaled hydraulic conductivity to the groundwater flow equation results in a hydraulic head which depends on the statistical parameters of the porous medium. It describes the drawdown of a transient pumping test in heterogeneous media. We used an ensemble of transient pumping test simulations to verify the up scaled drawdown solution. We generated transient pumping tests in heterogeneous media for various values of the statistical parameters variance and correlation length and evaluated their impact on the drawdown behavior as well as on the temporal evolution. We further examined the impact of several aspects like the location of an observation well or the local conductivity at the pumping well on the drawdown behavior. This work can be understood as an expansion of the work of Zech et al. [2012], where a corresponding method to interpret stationary well flow is presented. However steady state pumping tests require a high number of monitoring wells, where not only the number but also the location of the piezometers is of importance for the quality and reliability of estimation results of aquifer heterogeneity. By using temporally resolved drawdown data of transient pumping tests we can circumvent the lack of sparse data in space. Zech, A., C. L. Schneider, and S. Attinger, 2012, The Extended Thiem's solution: Including the impact of heterogeneity, Water Resour. Res., 48, W10535, doi:10.1029/2012WR011852.

Zech, Alraune; Attinger, Sabine

2014-05-01

36

Intelligent transient transitions detection of LRE test bed  

NASA Astrophysics Data System (ADS)

Health Monitoring Systems is an implementation of monitoring strategies for complex systems whereby avoiding catastrophic failure, extending life and leading to improved asset management. A Health Monitoring Systems generally encompasses intelligence at many levels and sub-systems including sensors, actuators, devices, etc. In this paper, a smart sensor is studied, which is use to detect transient transitions of liquid-propellant rocket engines test bed. In consideration of dramatic changes of variable condition, wavelet decomposition is used to work real time in areas. Contrast to traditional Fourier transform method, the major advantage of adding wavelet analysis is the ability to detect transient transitions as well as obtaining the frequency content using a much smaller data set. Historically, transient transitions were only detected by offline analysis of the data. The methods proposed in this paper provide an opportunity to detect transient transitions automatically as well as many additional data anomalies, and provide improved data-correction and sensor health diagnostic abilities. The developed algorithms have been tested on actual rocket test data.

Zhu, Fengyu; Shen, Zhengguang; Wang, Qi

2013-01-01

37

Transient model applications. 3: Transient engine simulation and analysis of an ice ingestion test  

NASA Astrophysics Data System (ADS)

A transient engine model capable of simulating the transient response of an aircraft engine ice ingestion is examined. This model is required to simulate a controlled test which would provide data with which the model could be verified. Ice ingestion testing is routinely conducted with the objective of demonstrating the ability of an aircraft engine to safely operate while an aircraft passes through a hail storm. The most critical test condition is at a flight idle power setting where the engine power is low (or the capability to melt ice and evaporate water is limited) and the concentration of hail relative to the engine inlet airflow is high. The ice ingestion test was accomplished with a set of ice guns which shot large quantities of uniformly distributed ice at the fan hub region (into the core of the engine). The ice was crushed and filtered to match the size of hail stones and fired at a velocity consistent with the air speed being represented by the test. The response of certain engine parameters, as predicted by the model, to the ice ingestion test, is graphically illustrated and discussed. Examples include fuel flow, fan speed, core speed, compressor discharge pressure, compressor discharge temperature.

McDonald, Peter W.

38

Analysis of Transient Pressure Tests for Olkaria Exploration Wells  

SciTech Connect

Analysis of transient pressure tests for Olkaria West wells shows that both infinite acting and double porosity models can be used to analyze the well behaviour and infer reservoir properties from fall-off steps of long enough duration, in wells where no significant thermal recovery occurs. The double porosity model gives better estimates of reservoir properties than the infinite acting model, for long fall-off steps in wells intercepting fractures. Semilog methods give fairly good estimates of reservoir transmissivity for the long fall-off steps but are highly inaccurate when used independently, especially for the short fall-off steps conducted in most of the wells. Double porosity models can also be used for recovery test analyses where two phase transients are not significant. 6 refs., 11 figs., 8 tabs.

Haukwa, Charles B.

1987-01-20

39

Temperature Dependence of Digital Single-Event Transients in Bulk and Fully-Depleted SOI Technologies  

E-print Network

Factors that affect single-event transient pulse widths, such as drift, diffusion, and parasitic bipolar transistor parameters, are also strong functions of operating temperature. In this paper, SET pulse-width measurements ...

Gouker, Pascale M.

40

Transient flight flutter test of a wing with tip tanks  

NASA Technical Reports Server (NTRS)

Wing flutter was encountered during flight testing of the F2H-2 airplane with full wing tip tanks. As a result, more refined theoretical analysis as well as flight flutter tests were initated to establish corrective measures and to experimentally verify the stability of the improved system. The results from the flight flutter tests, utilizing the transient response technique, are presented. The method of excitation consisted of abrupt deflections of the ailerons resulting from stick bangs and data were measured by wing tip accelerometers. A comparison of the results with theoretical predictions is presented and indicates that reasonably good correlation was obtained. The influence on wing flutter of tip tank fuel transfer cycle, which was incorporated to control the center of gravity range of the tank during defueling, is indicated by the measured results and compared with the theory. The final configuration utilized a transfer cycle which was proven stable as a result of flight flutter testing. It is concluded that transient response measurements resulting from stick bangs provide a reasonably reliable and safe technique of flight flutter testing for wings with external tanks or heavy stores.

Werdes, R. J.

1975-01-01

41

Tidal volume single-breath washin of SF6 and CH4 in transient microgravity  

NASA Technical Reports Server (NTRS)

We performed tidal volume single-breath washins (SBW) by using tracers of different diffusivity and varied the time spent in microgravity (microG) before the start of the tests to look for time-dependent effects. SF(6) and CH(4) phase III slopes decreased by 35 and 26%, respectively, in microG compared with 1 G (P < 0.05), and the slope difference between gases disappeared. There was no effect of time in microG, suggesting that neither the hypergravity period preceding microG nor the time spent in microG affected gas mixing at volumes near functional residual capacity. In previous studies using SF(6) and He (Lauzon A-M, Prisk GK, Elliott AR, Verbanck S, Paiva M, and West JB. J Appl Physiol 82: 859-865, 1997), the vital capacity SBW showed an increase in slope difference between gases in transient microG, the opposite of the decrease in sustained microG. In contrast, tidal volume SBW showed a decrease in slope difference in both microG conditions. Because it is only the behavior of the more diffusive gas that differed between maneuvers and microG conditions, we speculate that, in the previous vital capacity SBW, the hypergravity period preceding the test in transient microG provoked conformational changes at low lung volumes near the acinar entrance.

Dutrieue, Brigitte; Paiva, Manuel; Verbanck, Sylvia; Le Gouic, Marine; Darquenne, Chantal; Prisk, G. Kim

2003-01-01

42

Transient thermal model of the continuous single-wheel thin-strip casting process  

NASA Astrophysics Data System (ADS)

A transient heat-transfer model (STRIP1D) has been developed to simulate the single-roll continuous strip-casting process. The model predicts temperature in the solidifying strip coupled with heat transfer in the rotating wheel, using an explicit finite difference procedure. The model has been calibrated using strip thickness data from a test caster at ARMCO Inc. (Middletown, OH) and verified with a range of other available measurements. The strip/wheel interface contact resistance and heat transfer were investigated in particular, and an empirical formula to calculate this heat-transfer coefficient as a function of contact time was obtained. Wheel temperature and final strip thickness are investigated as a function of casting speed, liquid steel pool depth, superheat, coatings on the wheel hot surface, strip detachment point, wheel wall thickness, and wheel material.

Li, Guowei; Thomas, Brian G.

1996-06-01

43

Large transient fault current test of an electrical roll ring  

NASA Technical Reports Server (NTRS)

The space station uses precision rotary gimbals to provide for sun tracking of its photoelectric arrays. Electrical power, command signals and data are transferred across the gimbals by roll rings. Roll rings have been shown to be capable of highly efficient electrical transmission and long life, through tests conducted at the NASA Lewis Research Center and Honeywell's Satellite and Space Systems Division in Phoenix, AZ. Large potential fault currents inherent to the power system's DC distribution architecture, have brought about the need to evaluate the effects of large transient fault currents on roll rings. A test recently conducted at Lewis subjected a roll ring to a simulated worst case space station electrical fault. The system model used to obtain the fault profile is described, along with details of the reduced order circuit that was used to simulate the fault. Test results comparing roll ring performance before and after the fault are also presented.

Yenni, Edward J.; Birchenough, Arthur G.

1992-01-01

44

Pressure-Transient Testing of Water-Injection Wells  

Microsoft Academic Search

This paper presents an interpretation method for injectivity and falloff testing in a single-layer oil reservoir that is under waterflooding and develops analytical solutions for pressure and saturation distributions. The effects of relative permeability, wellbore storage, and skin are considered in these solutions. New field-dependent type curves for falloff tests, which exhibit features that do not appear in the currently

Maghsood Abbaszadeh; Medhat Kamal

1989-01-01

45

Two-dimensional steady-state and transient analysis of single-cell thermionic fuel elements  

SciTech Connect

A two-dimensional transient model is developed to simulate steady-state and transient operations of single-cell thermionic fuel elements (TFEs). Model predictions are in good agreement with published data to within 4.5 and 5.5% for fission and electrically heated TFEs of the TOPAZ-II type, respectively. In addition, the results of a transient analysis simulating the startup of an electrically heated TFE, following a step function increase in thermal power, are in presented and discussed.

El-Genk, M.S.; Xue, H. (Univ. of New Mexico, Albuquerque, NM (United States). Inst. for Space Nuclear Power Studies)

1994-10-01

46

Generation of single-cycle THz transients with high electric-field amplitudes  

Microsoft Academic Search

Single-cycle terahertz (THz) transients in the frequency range 0.3-7 THz with electric-field amplitudes of more than 400 kV\\/cm are generated by four-wave mixing of the fundamental and the second harmonic of 25 fs pulses from a Ti:sapphire amplifier in ionized air. These transients are fully characterized by electro-optic sampling with ZnTe and GaP crystals. One can tune the center frequency

T. Bartel; P. Gaal; K. Reimann; Michael Woerner; Thomas Elsaesser

2005-01-01

47

Modeling transient streaming potentials in falling-head permeameter tests.  

PubMed

We present transient streaming potential data collected during falling-head permeameter tests performed on samples of two sands with different physical and chemical properties. The objective of the work is to estimate hydraulic conductivity (K) and the electrokinetic coupling coefficient (Cl ) of the sand samples. A semi-empirical model based on the falling-head permeameter flow model and electrokinetic coupling is used to analyze the streaming potential data and to estimate K and Cl . The values of K estimated from head data are used to validate the streaming potential method. Estimates of K from streaming potential data closely match those obtained from the associated head data, with less than 10% deviation. The electrokinetic coupling coefficient was estimated from streaming potential vs. (1) time and (2) head data for both sands. The results indicate that, within limits of experimental error, the values of Cl estimated by the two methods are essentially the same. The results of this work demonstrate that a temporal record of the streaming potential response in falling-head permeameter tests can be used to estimate both K and Cl . They further indicate the potential for using transient streaming potential data as a proxy for hydraulic head in hydrogeology applications. PMID:23782328

Malama, Bwalya; Revil, André

2014-01-01

48

Time dependence of test fuel power coupling during Transient Reactor Test Facility irradiation experiments  

SciTech Connect

Studies have been conducted at the Transient Reactor Test Facility (TREAT) to determine the variation during transient irradiation experiments of the ratio of axial midplane test fuel power to reactor power as measured by ex-core ion chamber current. It is shown that the dependence of this ratio on core temperature is generally small. However, effects due to control rod motion can be substantial. A simple mathematical expression that predicts the dependence of this ratio on control rod position is shown to give good agreement with integral experimental data. This work makes possible refinements in obtaining the desired power-versus-time behavior in test fuel by accounting for the effects of instantaneous position of control rods and core temperature during transient operation.

Klotzkin, G.; Harrison, L.J.; Hart, P.; Swanson, R.W.

1984-02-01

49

TRANSPA: a code for transient thermal analysis of a single fuel pin  

SciTech Connect

An analytical model (TRANSPA) for the transient thermal analysis of a single uranium carbide fuel pin was developed. This model uses thermal boundary conditions obtained from COBRA-WC output and calculates the transient thermal response of a single fuel pin to changes in internal power generation, coolant flowrate, or fuel pin physical configuration. The model uses the MITAS finite difference thermal analyzer. MITAS provides the means to input separate conductance models through the use of a user subroutine input capability. The model is a lumped-mass representation of the fuel pin using 26 nodes and 42 conductors. Run time for each transient analysis is approximately one minute of central processor time on the NOS operating system.

Prenger, F.C.

1985-02-01

50

Digital Computer Solution of Electromagnetic Transients in Single-and Multiphase Networks  

Microsoft Academic Search

Electromagnetic transients in arbitrary single- or multiphase networks are solved by a nodal admittance matrix method. The formulation is based on the method of characteristics for distributed parameters and the trapezoidal rule of integration for lumped parameters. Optimally ordered triangular factorization with sparsity techniques is used in the solution. Examples and programming details illustrate the practicality of the method.

Hermann Dommel

1969-01-01

51

Arsenazo III and antipyrylazo III calcium transients in single skeletal muscle fibers  

PubMed Central

The metallochrome calcium indicators arsenazo III and antipyrylazo III have been introduced individually into cut single frog skeletal muscle fibers from which calcium transients have been elicited either by action potential stimulation or by voltage-clamp pulses of up to 50 ms in duration. Calcium transients recorded with both dyes at selected wavelengths have similar characteristics when elicited by action potentials. Longer voltage-clamp pulse stimulation reveals differences in the late phases of the optical signals obtained with the two dyes. The effects of different tension blocking methods on Ca transients were compared experimentally. Internal application of EGTA at concentrations up to 3 mM was demonstrated to be efficient in blocking movement artifacts without affecting Ca transients. Higher EGTA concentrations affect the Ca signals' characteristics. Differential effects of internally applied EGTA on tension development as opposed to calcium transients suggest that diffusion with binding from Ca++ release sites to filament overlap sites may be significant. The spectral characteristics of the absorbance transients recorded with arsenazo III suggest that in situ recorded signals cannot be easily interpreted in terms of Ca concentration changes. A more exhaustic knowledge of the dye chemistry and/or in situ complications in the use of the dye will be necessary. PMID:6802933

1982-01-01

52

Transient productivity index for numerical well test simulations  

SciTech Connect

The most difficult aspect of numerical simulation of well tests is the treatment of the Bottom Hole Flowing (BHF) Pressure. In full field simulations, this pressure is derived from the Well-block Pressure (WBP) using a numerical productivity index which accounts for the grid size and permeability, and for the well completion. This productivity index is calculated assuming a pseudo-steady state flow regime in the vicinity of the well and is therefore constant during the well production period. Such a pseudo-steady state assumption is no longer valid for the early time of a well test simulation as long as the pressure perturbation has not reached several grid-blocks around the well. This paper offers two different solutions to this problem: (1) The first one is based on the derivation of a Numerical Transient Productivity Index (NTPI) to be applied to Cartesian grids; (2) The second one is based on the use of a Corrected Transmissibility and Accumulation Term (CTAT) in the flow equation. The representation of the pressure behavior given by both solutions is far more accurate than the conventional one as shown by several validation examples which are presented in the following pages.

Blanc, G.; Ding, D.Y.; Ene, A. [Institut Francais du Petrole, Pau (France)] [and others

1997-08-01

53

Single Sample t-Test  

NSDL National Science Digital Library

This page will perform a t-test for the significance of the difference between the observed mean of a sample and a hypothetical mean of the population from which the sample is randomly drawn. The user will be asked to specify the sample size as the page opens.

Lowry, Richard, 1940-

2008-09-05

54

Successful Transient Expression of Cas9 and Single Guide RNA Genes in Chlamydomonas reinhardtii.  

PubMed

The clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 system has become a powerful and precise tool for targeted gene modification (e.g., gene knockout and gene replacement) in numerous eukaryotic organisms. Initial attempts to apply this technology to a model, the single-cell alga, Chlamydomonas reinhardtii, failed to yield cells containing edited genes. To determine if the Cas9 and single guide RNA (sgRNA) genes were functional in C. reinhardtii, we tested the ability of a codon-optimized Cas9 gene along with one of four different sgRNAs to cause targeted gene disruption during a 24-h period immediately following transformation. All three exogenously supplied gene targets as well as the endogenous FKB12 (rapamycin sensitivity) gene of C. reinhardtii displayed distinct Cas9/sgRNA-mediated target site modifications as determined by DNA sequencing of cloned PCR amplicons of the target site region. Success in transient expression of Cas9 and sgRNA genes contrasted with the recovery of only a single rapamycin-resistant colony bearing an appropriately modified FKB12 target site in 16 independent transformation experiments involving >10(9) cells. Failure to recover transformants with intact or expressed Cas9 genes following transformation with the Cas9 gene alone (or even with a gene encoding a Cas9 lacking nuclease activity) provided strong suggestive evidence for Cas9 toxicity when Cas9 is produced constitutively in C. reinhardtii. The present results provide compelling evidence that Cas9 and sgRNA genes function properly in C. reinhardtii to cause targeted gene modifications and point to the need for a focus on development of methods to properly stem Cas9 production and/or activity following gene editing. PMID:25239977

Jiang, Wenzhi; Brueggeman, Andrew J; Horken, Kempton M; Plucinak, Thomas M; Weeks, Donald P

2014-11-01

55

Single Event Transient Analysis of an SOI Operational Amplifier for Use in Low-Temperature Martian Exploration  

NASA Technical Reports Server (NTRS)

The next generation of Martian rover#s to be launched by JPL are to examine polar regions where temperatures are extremely low and the absence of an earth-like atmosphere results in high levels of cosmic radiation at ground level. Cosmic rays lead to a plethora of radiation effects including Single Event Transients (SET) which can severely degrade microelectronic functionality. As such, a radiation-hardened, temperature compensated CMOS Single-On-Insulator (SOI) Operational Amplifier has been designed for JPL by the University of Tennessee and fabricated by Honeywell using the SOI V process. SOI technology has been shownto be far less sensitive to transient effects than both bulk and epilayer Si. Broad beam heavy-ion tests at the University of Texas A&M using Kr and Xebeams of energy 25MeV/amu were performed to ascertain the duration and severity of the SET for the op-amp configured for a low and high gain application. However, some ambiguity regarding the location of transient formation required the use of a focused MeV ion microbeam. A 36MeV O6(+) microbeam. the Sandia National Laboratory (SNL) was used to image and verify regions of particular concern. This is a viewgraph presentation

Laird, Jamie S.; Scheik, Leif; Vizkelethy, Gyorgy; Mojarradi, Mohammad M; Chen, Yuan; Miyahira, Tetsuo; Blalock, Benjamin; Greenwell, Robert; Doyle, Barney

2006-01-01

56

Modeling and testing of a thermal transient anemometer  

SciTech Connect

The Thermal Transient Anemometer (TTA) is a fluid mass flow measuring device which utilizes a thermocouple as a probe. The probe is periodically heated by an electric current pulse through the thermocouple junction, and the measured rate of cooling between pulses is related to the local mean flow velocity. The standard thermocouple sensor provides an inexpensive flow probe which is durable, rugged, and capable of satisfactory operation in hostile environments. The TTA was developed and patented in prototype form by Instrument Development for Applied Physics (IDAP), a small US company. IDAP has tested the TTA and shown that the measurement principle is valid. However, there is a need to refine the prototype so that the TTA becomes a commercially viable instrument. The main concern is to reduce the heating current to the TTA so that battery-powered operation is possible. To do this, a probe needs to be developed such that only the region local to the thermocouple junction is heated, rather than the entire length of the wire. There area number of ways that this might be done, and IDAP has worked with ARi Industries, a thermocouple manufacturer, to develop probe designs that would have this characteristic, and at the same time would retain the ruggedness and ease of manufacture of a standard thermocouple. The purpose of this CRADA was to investigate these designs with a view to their possible commercial development. The starting point was to develop a computer model of the TTA as it currently exists, i.e., the prototype configuration, and to compare the results with experimental data. Good agreement between model and data was obtained, thus allowing new designs to be analyzed with some confidence.

Page, R.J.

1996-10-01

57

Single-photon avalanche diode arrays for fast transients and adaptive optics  

Microsoft Academic Search

An instrumentation based on a silicon monolithic array of 60 photon counters [single-photon avalanche diode array (SPADA)] for state-of-the-art measurements of fast transient phenomena and adaptive optics (AO) is presented. The fabricated solid-state photon counters are rugged, easy to be integrated in the optical system, free from read-out noise, and provide very fast frame rates (> 10 kHz) and nanosecond

Franco Zappa; Simone Tisa; Sergio Cova; Piera Maccagnani; Domenico Bonaccini Calia; Roberto Saletti; Roberto Roncella; Giovanni Bonanno; Massimiliano Belluso

2006-01-01

58

Deep level transient spectroscopic study of oxygen-implanted ZnO single crystal  

Microsoft Academic Search

ZnO single crystal samples were implanted by oxygen with the energy of 150keV. After the pretreatment of hydrogen peroxide [1], Schottky contacts were fabricated with Au film deposited by thermal evaporation. Deep level defects were studied by deep level transient spectroscopy (DLTS). The activation energy of the 0.29eV deep trap was observed in the as-implanted sample and samples anneal at

Ziran Ye; Guangwei Ding; Jincheng Fan; Chi Chung Ling

2011-01-01

59

Relationship of Lipid Rafts to Transient Confinement Zones Detected by Single Particle Tracking  

Microsoft Academic Search

We examined the physical and chemical characteristics of transient confinement zones (TCZs) that are detected in single particle trajectories of molecules moving within the membrane of C3H 10T1\\/2 murine fibroblasts and their relationship to “rafts.” We studied the lateral movement of different membrane molecules thought to partition to varying degrees into or out of the putative lipid domains known as

Christian Dietrich; Bing Yang; Takahiro Fujiwara; Akihiro Kusumi; Ken Jacobson

2002-01-01

60

The transient and qualitative performance of a self-excited single-phase induction generator  

SciTech Connect

The modeling and transient performance of a single-phase induction generator with series or parallel connected load is the theme of this paper. The system of equations are expressed in terms of flux linkages and includes the effect of magnetizing flux linkage saturation. Generator self-excitation and voltage collapse phenomena are simulated. The balance of the paper deals with the qualitative behavior of the generator using concepts of harmonic balance and system bifurcation.

Ojo, O. [Tennessee Technological Univ., Cookeville, TN (United States). Dept. of Electrical Engineering] [Tennessee Technological Univ., Cookeville, TN (United States). Dept. of Electrical Engineering

1995-09-01

61

Single event transient modeling and mitigation techniques for mixed-signal delay locked loop (DLL) and clock circuits  

NASA Astrophysics Data System (ADS)

The purpose of this PhD work has been to investigate, model, test, develop and provide hardening techniques and guidelines for the mitigation of single event transients (SETs) in analog mixed-signal (AMS) delay locked loops (DLLs) for radiation-hardened applications. Delay-locked-loops (DLLs) are circuit substructures that are present in complex ASIC and system-on-a-chip designs. These circuits are widely used in on-chip clock distribution systems to reduce clock skew, to reduce jitter noise, and to recover clock signals at regional points within a global clock distribution system. DLLs are critical to the performance of many clock distribution systems, and in turn, the overall performance of the associated integrated system; as such, complex systems often employ multiple DLLs for clock deskew and distribution tasks. In radiation environments such as on-orbit, these critical circuits represent at-risk points of malfunction for large sections of integrated circuits due to vulnerabilities to radiation-generated transients (i.e. single event transients) that fan out across the system. The analysis of single event effects in analog DLLs has shown that each DLL sub-circuit primitive is vulnerable to single event transients. However, we have identified the voltage controlled delay line (VCDL) sub-circuit as the most sensitive to radiation-induced single event effects generating missing clock pulses that increase with the operating frequency of the circuit. This vulnerability increases with multiple instantiation of DLLs as clock distribution nodes throughout an integrated system on a chip. To our knowledge, no complete work in the rad-hard community regarding the hardening of mixed-signal DLLs against single event effects (missing pulses) has been developed. Most of the work present in the literature applies the "brute force" and well-established digital technique of triple modular redundancy (TMR) to the digital subcomponents. We have developed two novel design techniques for the mitigation of DLL missing pulses that are fully implementable in modern CMOS technologies. These techniques offer to the community the choice of hardening using a restoring current technique in the VCDL sub-circuit to inhibit the creation of missing pulse errors, or using a combinational logic error monitoring technique to correct missing pulses after they occur in real time. We have implemented both of these techniques with minimal area and power penalties when compared to TMR. In addition, these hardening techniques have been extrapolated to other clock circuits, such as digital PLLs. The first hardening technique uses a hardened complementary differential pair VCDL to increase the critical charge (Qcrit) necessary for single event transient generation and thus mitigate missing pulses at the source. Our implementation of this technique at 180 nm, 90 nm and 40 nm required less than a 2% area penalty over a non-hardened design. To experimentally validate this technique, hardened VCDLs were designed and fabricated in 180-nm IBM and 40-nm UMC technologies, then tested at the Naval Research Lab in Washington D.C. The second hardening technique, based on combinational logic pulse monitoring, uses an error correction circuit to mitigate the missing pulses as they occur. This ECC technique is implemented via a "peeled" VCDL (i.e. each transistor is split in area but doubled in multiplicity). We have shown the effectiveness of this technique by implementing it in a Xilinx Virtex 5 FPGA. Furthermore, this new ECC technique is independent of technology scaling -- a highly valuable attribute for sub-50 nm design applications. In addition to the formulation, simulation, prototyping, fabrication, and testing of these new hardening solutions, we developed a unique single event analytical model to guide future hardened DLL designs at advanced technology nodes. The model was furthermore generalized to PLL and DLLs. These analytical models were then used to provide a set of equations to the designer for important insight into hardening choices an

Maillard, Pierre

62

Single Event Effect (SEE) Test Planning 101  

NASA Technical Reports Server (NTRS)

This is a course on SEE Test Plan development. It is an introductory discussion of the items that go into planning an SEE test that should complement the SEE test methodology used. Material will only cover heavy ion SEE testing and not proton, LASER, or other though many of the discussed items may be applicable. While standards and guidelines for how-to perform single event effects (SEE) testing have existed almost since the first cyclotron testing, guidance on the development of SEE test plans has not been as easy to find. In this section of the short course, we attempt to rectify this lack. We consider the approach outlined here as a "living" document: mission specific constraints and new technology related issues always need to be taken into account. We note that we will use the term "test planning" in the context of those items being included in a test plan.

LaBel, Kenneth A.; Pellish, Jonathan; Berg, Melanie D.

2011-01-01

63

Built-In Self-Test of Field Programmable Analog Arrays based on Transient Response Analysis  

Microsoft Academic Search

In this work a strategy for testing analog networks, known as Transient Response Analysis Method, is applied to test the Configurable\\u000a Analog Blocks (CABs) of Field Programmable Analog Arrays (FPAAs). In this method the Circuit Under Test (CUT) is programmed\\u000a to implement first and second order blocks and the transient response of these blocks to known input stimuli is analyzed.

Tiago R. Balen; José Vicente Calvano; Marcelo Lubaszewski; Michel Renovell

2007-01-01

64

Single event phenomena: Testing and prediction  

NASA Technical Reports Server (NTRS)

Highly integrated microelectronic devices are often used to increase the performance of satellite systems while reducing the system power dissipation, size, and weight. However, these devices are usually more susceptible to radiation than less integrated devices. In particular, the problem of sensitivity to single event upset and latchup is greatly increased as the integration level is increased. Therefore, a method for accurately evaluating the susceptibility of new devices to single event phenomena is critical to qualifying new components for use in space systems. This evaluation includes testing devices for upset or latchup and extrapolating the results of these tests to the orbital environment. Current methods for testing devices for single event effects are reviewed, and methods for upset rate prediction, including a new technique based on Monte Carlo simulation, are presented.

Kinnison, James D.

1992-01-01

65

Curing dynamics of photopolymers measured by single-shot heterodyne transient grating method.  

PubMed

The heterodyne transient grating (HD-TG) method was first applied to the curing dynamics measurement of photopolymers. The curing dynamics for various monomers including an initiator (2.5 vol%) was monitored optically via the refractive index change after a single UV pulse irradiation. We could obtain the polymerization time and the final change in the refractive index, and the parameters were correlated with the viscosity, molecular structure, and reaction sites. As the polymerization time was longer, the final refractive change was larger, and the polymerization time was explained in terms of the monomer properties. PMID:23574665

Arai, Mika; Fujii, Tomomi; Inoue, Hayato; Kuwahara, Shota; Katayama, Kenji

2013-01-01

66

Pressure transient testing and productivity analysis for horizontal wells  

E-print Network

-source solution in an infinite reservoir with no-flow boundaries at the top and bottom, and infinite-acting boundaries at the lateral sides. Babu and Odeh3-4 obtained a point source function using the same plane sources in all three directions (x, y and z... analysis in reservoirs with impermeable top- and bottom-boundaries. Babu and Odeh3-4 developed closed expressions for transient pressure response, and a general model for pseudo-steady-state flow. The models presented by Babu and Odeh3-4 are suitable...

Cheng, Yueming

2004-11-15

67

Methods Studies on System Identification from Transient Rotor Tests  

NASA Technical Reports Server (NTRS)

Some of the more important methods are discussed that have been used or proposed for aircraft parameter identification. The methods are classified into two groups: Equation error or regression estimates and Bayesian estimates and their derivatives that are based on probabilistic concepts. In both of these two groups the cost function can be optimized either globally over the entire time span of the transient, or sequentially, leading to the formulation of optimum filters. Identifiability problems and the validation of the estimates are briefly outlined, and applications to lifting rotors are discussed.

Hohenemser, K. H.; Banerjee, D.; Yin, S. K.

1975-01-01

68

Extended overpower transient testing of LMFBR oxide pins in EBR-II  

SciTech Connect

As part of a joint effort between the Power Reactor and Nuclear Fuel Development Corporation of Japan and the US Department of Energy, a series of five extended slow overpower transient tests are being conducted in the Experimental Breeder Reactor-II (EBR-II) on preirradiated mixed oxide fuel and blanket pins. In the first two tests conducted in the series, fuel and blanket pins were subjected to a 0.1%/s power ramp to approx. 60% overpower before the transient termination. None of the test pins breached during the transient. A significant cladding breaching margin over the normal PPS trip setting of approx. 12 to 15% was thus demonstrated for the 0.1%/s ramp. The transient-induced pin cladding strains, caused principally by fuel-cladding mechanical interaction, were small but measurable.

Tsai, H.; Neimark, L.A.; Tani, S.; Shibahara, I.

1985-01-01

69

Transient x-ray diffraction to measure the dynamic response of shocked lithium fluoride single crystal  

NASA Astrophysics Data System (ADS)

Transient x-ray diffraction, also called time-resolved x-ray diffraction and dynamic x-ray diffraction, is one novel diagnostic technique for probing shocked solids. It can provide direct information about microscopic mechanisms governing shock-induced deformation and structural changes at atomistic scales with nanosecond and picoseconds resolution, and lately, it has become possible to measure the structure of transients with sub-picoseconds and sub-Angstrom resolution with the development of ultrafast lasers which can produce femtosecond electron and x-ray pulses in the form of characteristics emission lines as well as x-ray continua in the keV range. In this paper, we detect and measure directly the dynamic response of lithium fluoride single crystal shocked compressed by laser irradiation in SHENGUANG II. In our experiments, high-intensity lasers irradiated a thin Cu foil to generate helium-like rays as x-ray source. Film (IP--image plate) recorded x rays diffracted from multiple lattice planes both perpendicular and oblique angles to the shock loading direction [100]. We gained the diffraction signals of the lattice planes (200) shocked and unshocked, what's more, other lattices (113), (1-13). The positions of the diffraction lines associated with the (200) lattice plane indicated compression of the lattice along [100] direction by 13%. In the experiment, a large-angle detector consists of two films-one rectangular in shape,one triangular in shape that are positioned to record x rays diffracted from a shocked single crystal nearly within a full ? steradian. The experiment shows that transient x-ray diffraction can diagnose the dynamical response of solid with higher resolution.

Wang, Hai-rong; Ye, Yan; Yang, Qing-guo; Li, Mu; Xiao, Sha-li; Li, Ze-ren

2013-08-01

70

An Investigation of the Ability to Recover from Transients Following Failures for Single-Pilot Rotorcraft  

NASA Technical Reports Server (NTRS)

A moving-base simulation was conducted to investigate a pilot's ability to recover from transients following single-axis hard-over failures of the flight-control system. The investigation was performed in conjunction with a host simulation that examined the influence of control modes on a single pilot's ability to perform various mission elements under high-workload conditions. The NASA Ames large-amplitude-motion Vertical Motion Simulator (VMS) was utilized, and the experimental variables were the failure axis, the severity of the failure, and the airspeed at which the failure occurred. Other factors, such as pilot workload and terrain and obstacle proximity at the time of failure, were kept as constant as possible within the framework of the host simulation task scenarios. No explicit failure warnings were presented to the pilot. Data from the experiment are shown, and pilot ratings are compared with the proposed handling-qualities requirements for military rotorcraft. Results indicate that the current proposed failure transient requirements may need revision.

Mansur, M. Hossein; Schroeder, Jeffery A.

1988-01-01

71

NEXT Single String Integration Test Results  

NASA Technical Reports Server (NTRS)

As a critical part of NASA's Evolutionary Xenon Thruster (NEXT) test validation process, a single string integration test was performed on the NEXT ion propulsion system. The objectives of this test were to verify that an integrated system of major NEXT ion propulsion system elements meets project requirements, to demonstrate that the integrated system is functional across the entire power processor and xenon propellant management system input ranges, and to demonstrate to potential users that the NEXT propulsion system is ready for transition to flight. Propulsion system elements included in this system integration test were an engineering model ion thruster, an engineering model propellant management system, an engineering model power processor unit, and a digital control interface unit simulator that acted as a test console. Project requirements that were verified during this system integration test included individual element requirements ; integrated system requirements, and fault handling. This paper will present the results of these tests, which include: integrated ion propulsion system demonstrations of performance, functionality and fault handling; a thruster re-performance acceptance test to establish baseline performance: a risk-reduction PMS-thruster integration test: and propellant management system calibration checks.

Soulas, George C.; Patterson, Michael J.; Pinero, Luis; Herman, Daniel A.; Snyder, Steven John

2010-01-01

72

Final Report for TREAT Transient Overpower Tests R9 and R12 -- Part 2  

SciTech Connect

Tests R9 and R12 were the first in-pile simulations of a 50c/s transient overpower (TOP) hypothetical core-disruptive accident (HCDA) as expected in the Fast Test Reactor (FTR). The tests employed prototypic thermal-hydraulic inlet and initial conditions, and used full-length FTR, fresh fuel pins. The initial conditions and power histories of tl1e two tests were prescribed alike to a point after the initial dbruptive pin failures. Test R9, the first of the two, provided data on the unterminated transient and was used to tailor the termination of test R12. Test R9 was allowed to continue on the overpower transient to the full energy capability of the Transient Test Reactor (TREAT) facility. This ensured failure of the test-bundle, but resulted in overpowering the test well beyond the predicted FTR response to the 50c/s HCDA TOP. Test R12, with the benefit of R9 transient data, was designed to scram TREAT just after the initial disruptive pin failures. Thereby, the response of test R12 was as close as possible to the actual FTR response to this HCDA as could be simulated in TREAT. Both R9 and R12 had objectives to examine the transient fuel motion due to the 50c/s TOP. Additional objectives were for R9 to examine fuel sweepout and for R12 to determine post-fuel relocation test section coolability. The results of the experiments demonstrated sweepout downstream of the active fuel zone: R9 - 50% and R12 - 5% of the total fuel inventory. Due to the excess input energy in test R9, the coolant channel was totally blocked in the region of the upper reflectors. Termination of the transient after the initial disruptive fuel pin failures in R12 resulted in less fuel motion, but allowed the coolant flow to return to 100% of full flow and quickly cool the test section. The termination of the R12 transient was accomplished by a flow meter signal feedback to the TREAT control computer. The test results indicate that: 1. The sweepout of fuel was dispersive and a coolable geometry remained. 2. The margin between fuel failure and normal operation power levels is high (several times nominal power); and, 3. Explosive, energetic vaporization events were not observed.

Koopman, R. N.; Murphy, W. F.; Fink, C. L.; Kramer, N. A.; Stewart, R. R.

1980-04-01

73

Exciton dynamics in single-walled nanotubes:?Transient photoinduced dichroism and polarized emission  

NASA Astrophysics Data System (ADS)

Ultrafast relaxation of photoexcitations in semiconducting single-walled carbon nanotubes ( S -NTs) were investigated using polarized pump-probe photomodulation (with 150 fs time resolution) and cw polarized photoluminescence (PL). Both annealed and unannealed thin NT films and D2O solutions of isolated NTs were investigated. Various transient photoinduced bleaching (PB) and photoinduced absorption (PA) bands, which show photoinduced dichroism, were observed in the ultrafast photomodulation spectra of all NT forms. The PA and PB decay dynamics as a function of time, t , follow a power law, (t)-? with ? in the range of 0.7 to 1. Whereas the PA bands in S -NTs in solution uniformly decay, the PB bands, in contrast, have different decay dynamics across the spectrum, which originates from an ultrafast spectral shift. Nevertheless the dynamics of the PA and PB bands for NTs in solution are the same when the spectral shift is accounted for, indicating a common origin. In addition S -NTs in D2O solution show polarized PL emission bands in the mid infrared spectral range that follow almost exactly the infrared absorption peaks of the isolated NTs, as well as their transient PB spectrum. The PL emission shows a degree of polarization that agrees with that of the transient photoinduced dichroism. We therefore conclude that the primary photoexcitations in S -NTs are not free carriers, rather they are excitons that are confined along the nanotubes. We found that the transient relaxation kinetics of the excitons depend on the NT form. The fastest exciton dynamics (with sub-picosecond lifetime) characterizes the annealed film, whereas the slowest dynamics (with lifetime of tens of ps) characterizes the isolated NTs in D2O solution. From the polarization memory decay we could estimate the diffusion constant, D , and the diffusion length, LD , of the excitons along the nanotube. For the annealed films at room temperature we found D?100cm2s-1 and LD?100nm . From the average PL polarization degree, which remains constant across the PL spectrum, and the transient polarization memory decay, we estimate the PL lifetime in NT solution to be of the order of 500 ps. This relatively long PL lifetime is dominated by nonradiative decay processes, which when coupled with the minute PL emission quantum efficiency indicates a very small radiative recombination rate. The weak radiative transition strength is consistent with recent excited state calculations that include electron-hole interaction, which predict that excitons in NTs are basically dark.

Sheng, C.-X.; Vardeny, Z. V.; Dalton, A. B.; Baughman, R. H.

2005-03-01

74

Luminescence of transient single cavitation bubbles in non-aqueous liquids produced by the modified tube-arrest method  

NASA Astrophysics Data System (ADS)

Large transient single bubbles of effective diameters in centimetres were generated by the modified tube-arrest method in 7 nonaqueous liquids besides water and in glycerin-water mixtures. During collapse, nearly all these bubbles gave off light emissions of various intensities, which in 6 liquids were correlated with the saturation vapour pressure and viscosity of the respective liquid. Bubbles in ethylene glycol and propylene glycol did not follow this rule, but those in the former liquid showed some unusual regularity in luminescence variation and the bubbles in both the liquids were particularly bright. The luminous properties of the transient single bubble are compared with those of the usual stable single bubble.

Wu, Xian-Mei; Ying, Chong-Fu; Li, Chao

2005-05-01

75

Comparison of Above Bandgap Laser and MeV Ion Induced Single Event Transients in High-Speed Si Photonic Devices  

NASA Technical Reports Server (NTRS)

We illustrate inherent differences between Single Event Transients generated by an above bandgap picosecond lasers and MeV heavy ions by comparing transient currents collected with an ion microbeam and picosecond laser with varying track waist.

Laird, Jamie S.; Hirao, Toshio; Onoda, Shinobu; Itoh, Hisayoshi; Edmonds, Larry; Johnston, Allan

2006-01-01

76

Aspects of using the IEC 61000-4-20 for transient testing with broadband signals  

Microsoft Academic Search

This paper concentrates on the usage of the IEC 61000-4-20, the international standard for emission and immunity testing in transverse electromagnetic (TEM) waveguides. The specifications for transient testing in TEM waveguides according to Annex C of the norm are verified by measurements with different waveguides (GTEM 1250 and GTEM 3750) and various excitation signals with a large bandwidth up to

Holger Thye; Dirk Zamow; Michael Koch; Heyno Garbe

2008-01-01

77

SEMICONDUCTOR DEVICES Negative bias temperature instability induced single event transient pulse narrowing and broadening  

NASA Astrophysics Data System (ADS)

The effect of negative bias temperature instability (NBTI) on a single event transient (SET) has been studied in a 130 nm bulk silicon CMOS process based on 3D TCAD device simulations. The investigation shows that NBTI can result in the pulse width and amplitude of SET narrowing when the heavy ion hits the PMOS in the high-input inverter; but NBTI can result in the pulse width and amplitude of SET broadening when the heavy ion hits the NMOS in the low-input inverter. Based on this study, for the first time we propose that the impact of NBTI on a SET produced by the heavy ion hitting the NMOS has already been a significant reliability issue and should be of wide concern, and the radiation hardened design must consider the impact of NBTI on a SET.

Jianjun, Chen; Shuming, Chen; Bin, Liang; Biwei, Liu

2010-12-01

78

Photoinduced transient mid-infrared absorption in single-walled carbon nanotubes  

NASA Astrophysics Data System (ADS)

We have performed optical pump - mid-infrared (MIR) probe spectroscopy on single-walled carbon nanotubes (SWNTs). The second excitonic absorption band (E22) of (6,5) SWNTs was resonantly excited and the resulting photoinduced absorption was monitored in the MIR range (3.5 -- 5.5 ?m) in a time range up to several hundred ps. Carrageenan films containing individualized CoMoCAT SWNTs formed on sapphire substrates were used for the measurement. This sample is optically transparent in the ˜3.5 -- 6 ?m region, where the transition of E11 excitons from the lowest dark state (1g) to the second bright state (2u) is expected to be observed. Our preliminary data shows the existence of photoinduced absorption in the investigated range. The origin of the observed transient absorption will be discussed.

Murakami, Yoichi; Rice, William; Kono, Junichiro

2007-03-01

79

Applications of convolution and deconvolution to transient well tests  

SciTech Connect

This paper presents the application of convolution and deconvolution interpretation methods. Two well-test field examples, interpreted with these methods, suggest that the downhole flow rate is crucial for system identification and parameter estimation and that the wellbore volume below the pressure gauge and flowmeter must be taken into account. A generalized rate-convolution method is presented to obtain the reservoir pressure. This new method gives better results than both the Horner and modified Horner methods. A new formula also is presented to determine the vertical permeability for partially penetrated wells.

Kuchuk, F.J. (Schlumberger-Doll Research Center, Ridgefield, CT (US))

1990-12-01

80

Experimental data report for transient flow calibration facility tests IIB101, IIB102 and IIB201  

SciTech Connect

Thermal-hydraulic response data are presented for the transient performance tests of a pitot tube rake (IIB201) and a modular drag disc-turbine transducer (DTT) rake (IIB101, IIB102). The tests were conducted in a system which provided full scale simulation of the pressure vessel and broken loop hot leg piping of the Loss of Fluid Test Facility (LOFT). A load cell system was used to provide a reference mass flow rate measurement.

Wambach, J.L.

1980-06-17

81

49 CFR 232.305 - Single car air brake tests.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Single car air brake tests. 232.305 Section 232.305...and Testing Requirements § 232.305 Single car air brake tests. (a) Single car air brake tests shall be performed by a...

2013-10-01

82

49 CFR 232.305 - Single car air brake tests.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Single car air brake tests. 232.305 Section 232.305...and Testing Requirements § 232.305 Single car air brake tests. (a) Single car air brake tests shall be performed by a...

2011-10-01

83

49 CFR 232.305 - Single car air brake tests.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Single car air brake tests. 232.305 Section 232.305...and Testing Requirements § 232.305 Single car air brake tests. (a) Single car air brake tests shall be performed by a...

2010-10-01

84

49 CFR 232.305 - Single car air brake tests.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Single car air brake tests. 232.305 Section 232.305...and Testing Requirements § 232.305 Single car air brake tests. (a) Single car air brake tests shall be performed by a...

2012-10-01

85

Transient Lift-off Test Results for an Experimental Hybrid Bearing in Air  

E-print Network

A hybrid bearing designed for use in a next generation turbo-pump is evaluated for the performance of initial lift-off, referred to as start-transient. The radial test rig features a high-speed spindle motor capable of 20,000 rpm that drives a 718...

Klooster, David

2011-02-22

86

Deriving solar transient characteristics from single spacecraft STEREO\\/HI elongation variations: a theoretical assessment of the technique  

Microsoft Academic Search

Recently, a technique has been developed whereby the radial velocity, Vr, and longitude direction, beta, of propagation of an outward-moving solar transient, such as a Coronal Mass Ejection (CME), can be estimated from its track in a time-elongation map produced using Heliospheric Imager (HI) observations from a single STEREO spacecraft. The method employed, which takes advantage of an artefact of

A. O. Williams; J. A. Davies; S. E. Milan; A. P. Rouillard; C. J. Davis; C. H. Perry; R. A. Harrison

2009-01-01

87

Luminescence of transient single cavitation bubbles in non-aqueous liquids produced by the modified tube-arrest method  

Microsoft Academic Search

Large transient single bubbles of effective diameters in centimetres were generated by the modified tube-arrest method in 7 nonaqueous liquids besides water and in glycerin-water mixtures. During collapse, nearly all these bubbles gave off light emissions of various intensities, which in 6 liquids were correlated with the saturation vapour pressure and viscosity of the respective liquid. Bubbles in ethylene glycol

Xian-Mei Wu; Chong-Fu Ying; Chao Li

2005-01-01

88

Method of Generating Transient Equivalent Sink and Test Target Temperatures for Swift BAT  

NASA Technical Reports Server (NTRS)

The NASA Swift mission has a 600-km altitude and a 22 degrees maximum inclination. The sun angle varies from 45 degrees to 180 degrees in normal operation. As a result, environmental heat fluxes absorbed by the Burst Alert Telescope (BAT) radiator and loop heat pipe (LHP) compensation chambers (CCs) vary transiently. Therefore the equivalent sink temperatures for the radiator and CCs varies transiently. In thermal performance verification testing in vacuum, the radiator and CCs radiated heat to sink targets. This paper presents an analytical technique for generating orbit transient equivalent sink temperatures and a technique for generating transient sink target temperatures for the radiator and LHP CCs. Using these techniques, transient target temperatures for the radiator and LHP CCs were generated for three thermal environmental cases: worst hot case, worst cold case, and cooldown and warmup between worst hot case in sunlight and worst cold case in the eclipse, and three different heat transport values: 128 W, 255 W, and 382 W. The 128 W case assumed that the two LHPs transport 255 W equally to the radiator. The 255 W case assumed that one LHP fails so that the remaining LHP transports all the waste heat from the detector array to the radiator. The 382 W case assumed that one LHP fails so that the remaining LHP transports all the waste heat from the detector array to the radiator, and has a 50% design margin. All these transient target temperatures were successfully implemented in the engineering test unit (ETU) LHP and flight LHP thermal performance verification tests in vacuum.

Choi, Michael K.

2004-01-01

89

Transient excitation and mechanical admittance test techniques for prediction of payload vibration environments  

NASA Technical Reports Server (NTRS)

Transient excitation forces were applied separately to simple beam-and-mass launch vehicle and payload models to develop complex admittance functions for the interface and other appropriate points on the structures. These measured admittances were then analytically combined by a matrix representation to obtain a description of the coupled system dynamic characteristics. Response of the payload model to excitation of the launch vehicle model was predicted and compared with results measured on the combined models. These results are also compared with results of earlier work in which a similar procedure was employed except that steady-state sinusoidal excitation techniques were included. It is found that the method employing transient tests produces results that are better overall than the steady state methods. Furthermore, the transient method requires far less time to implement, and provides far better resolution in the data. However, the data acquisition and handling problem is more complex for this method. It is concluded that the transient test and admittance matrix prediction method can be a valuable tool for development of payload vibration tests.

Kana, D. D.; Vargas, L. M.

1977-01-01

90

Mobile automated high-speed transient data recording and transmission system. [For underground nuclear test data  

Microsoft Academic Search

A CAMAC-based mobile automated high-speed transient data recording and transmission system developed for gathering underground nuclear test data in remote areas at the Nevada Test Site is described. The system, which is comprised of a NOVA-820 computer and measurement instrumentation packages interfaced via CAMAC modules, permits baseline and zero-time data to be recorded and transmitted automatically in digital form via

Antuna

1977-01-01

91

Effects of Ca2+ on the transient outward current of single isolated Helix central neurones.  

PubMed Central

1. Single Helix neurones were studied under voltage-clamp conditions with internal perfusion in order to examine the contribution of internal and external Ca2+ and the effects of 4-aminopyridine (4-AP) on the transient outward current (IA). 2. In Na+ -free snail Ringer, replacement of external Ca2+ [( Ca2+]o) with equimolar Co2+ reduced the maximum amplitude of IA and induced a shift of the steady-state part of the IA inactivation curve (I-V curve), in a positive direction along the voltage axis when the neurone was internally perfused with K-aspartate. 3. In Ca2+ -free solutions, precipitation or chelation of internal Ca2+ [( Ca2+]i) by internal perfusion with KF or EGTA shifted the curve in a more negative direction without affecting the maximum amplitude of IA. Thus, the kinetics of IA are dependent not only upon [Ca2+]o, as previously suggested, but also upon [Ca2+]i. 4. In the presence of 4-AP the I-V curve for IA shifted in a hyperpolarizing direction and the maximal amplitude was reduced when the neurone was internally perfused with K-aspartate. However, 4-AP had little or no effect on the I-V relationship of IA when the neurone was internally perfused with the Ca2+ precipitating or chelating agent, KF or EGTA. These results suggest that the actions of 4-AP on IA are at least partly dependent upon [Ca2+]i. PMID:2852523

Tsuda, Y.; Oyama, Y.; Carpenter, D. O.; Akaike, N.

1988-01-01

92

49 CFR 238.311 - Single car test.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Single car test. 238.311 Section 238.311 Transportation...Passenger Equipment § 238.311 Single car test. (a) Except for self-propelled passenger cars, single car tests of all passenger...

2011-10-01

93

49 CFR 238.311 - Single car test.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Single car test. 238.311 Section 238.311 Transportation...Passenger Equipment § 238.311 Single car test. (a) Except for self-propelled passenger cars, single car tests of all passenger...

2012-10-01

94

49 CFR 238.311 - Single car test.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Single car test. 238.311 Section 238.311 Transportation...Passenger Equipment § 238.311 Single car test. (a) Except for self-propelled passenger cars, single car tests of all passenger...

2013-10-01

95

49 CFR 238.311 - Single car test.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Single car test. 238.311 Section 238.311 Transportation...Passenger Equipment § 238.311 Single car test. (a) Except for self-propelled passenger cars, single car tests of all passenger...

2010-10-01

96

Single Event Effects (SEE) Testing of Embedded DSP Cores within Microsemi RTAX4000D Field Programmable Gate Array (FPGA) Devices  

NASA Technical Reports Server (NTRS)

Motivation for this work is: (1) Accurately characterize digital signal processor (DSP) core single-event effect (SEE) behavior (2) Test DSP cores across a large frequency range and across various input conditions (3) Isolate SEE analysis to DSP cores alone (4) Interpret SEE analysis in terms of single-event upsets (SEUs) and single-event transients (SETs) (5) Provide flight missions with accurate estimate of DSP core error rates and error signatures.

Perez, Christopher E.; Berg, Melanie D.; Friendlich, Mark R.

2011-01-01

97

The dipole flow test: A new single-borehole test for aquifer characterization  

SciTech Connect

A new single-borehole measurement technique for confined aquifers, the dipole flow test, yields the vertical distributions of the horizontal hydraulic conductivity, the vertical hydraulic conductivity, and the specific storativity when applied to different borehole intervals. The test utilizes straddle packers to isolate two chambers in the borehole, pressure transducers to monitor drawdown in them, and a small pump to create a dipole flow pattern in the aquifer by pumping water at a constant rate from the aquifer into one chamber, transferring it within the well to the next chamber, and finally injecting it back to the aquifer. A mathematical model describing the drawdown in each chamber is derived for the transient as well as the steady state cases. The aquifer parameters may be estimated from data produced by the dipole flow test alone or in conjunction with conventional pumping tests. The dipole flow regime reaches a steady state relatively quickly, especially in well permeable aquifers. A robust computational methodology for estimating the aquifer parameters, suitable for automatization, is based on the Newton-Raphson algorithm applied to a system of up to three nonlinear equations, each describing the well drawdown at a different judiciously chosen time. Due to the relatively small drawdown it invokes, the dipole flow test may be applicable to unconfined aquifers as well.

Kabala, Z.J. (Univ. of California, Riverside (United States))

1993-01-01

98

An infrastructure for accurate characterization of single-event transients in digital circuits?  

PubMed Central

We present the architecture and a detailed pre-fabrication analysis of a digital measurement ASIC facilitating long-term irradiation experiments of basic asynchronous circuits, which also demonstrates the suitability of the general approach for obtaining accurate radiation failure models developed in our FATAL project. Our ASIC design combines radiation targets like Muller C-elements and elastic pipelines as well as standard combinational gates and flip-flops with an elaborate on-chip measurement infrastructure. Major architectural challenges result from the fact that the latter must operate reliably under the same radiation conditions the target circuits are exposed to, without wasting precious die area for a rad-hard design. A measurement architecture based on multiple non-rad-hard counters is used, which we show to be resilient against double faults, as well as many triple and even higher-multiplicity faults. The design evaluation is done by means of comprehensive fault injection experiments, which are based on detailed Spice models of the target circuits in conjunction with a standard double-exponential current injection model for single-event transients (SET). To be as accurate as possible, the parameters of this current model have been aligned with results obtained from 3D device simulation models, which have in turn been validated and calibrated using micro-beam radiation experiments at the GSI in Darmstadt, Germany. For the latter, target circuits instrumented with high-speed sense amplifiers have been used for analog SET recording. Together with a probabilistic analysis of the sustainable particle flow rates, based on a detailed area analysis and experimental cross-section data, we can conclude that the proposed architecture will indeed sustain significant target hit rates, without exceeding the resilience bound of the measurement infrastructure. PMID:24748694

Savulimedu Veeravalli, Varadan; Polzer, Thomas; Schmid, Ulrich; Steininger, Andreas; Hofbauer, Michael; Schweiger, Kurt; Dietrich, Horst; Schneider-Hornstein, Kerstin; Zimmermann, Horst; Voss, Kay-Obbe; Merk, Bruno; Hajek, Michael

2013-01-01

99

THEORETICAL ANALYSIS OF THE TRANSIENT PRESSURE RESPONSE FROM A CONSTANT FLOW RATE HYDRAULIC CONDUCTIVITY TEST.  

USGS Publications Warehouse

Incorporating a flow pump into a conventional triaxial laboratory system allows fluid to be supplied to or withdrawn from the base of a sediment sample at small and constant rates. An initial transient record of hydraulic head versus time is observed which eventually stabilizes to a constant steady state gradient across the sample; values of hydraulic conductivity can subsequently be determined from Darcy's law. In this paper, analytical methods are presented for determining values of specific storage and hydraulic conductivity from the initial transient phase of such a constant flow rate test. These methods are based on a diffusion equation involving pore pressure and are analogous to those used to describe the soil consolidation process and also to interpret aquifer properties from pumping tests.

Morin, Roger, H.; Olsen, Harold, W.

1987-01-01

100

Heat and mass release for some transient fuel source fires: A test report  

SciTech Connect

Nine fire tests using five different trash fuel source packages were conducted by Sandia National Laboratories. This report presents the findings of these tests. Data reported includes heat and mass release rates, total heat and mass release, plume temperatures, and average fuel heat of combustion. These tests were conducted as a part of the US Nuclear Regulatory Commission sponsored fire safety research program. Data from these tests were intended for use in nuclear power plant probabilistic risk assessment fire analyses. The results were also used as input to a fire test program at Sandia investigating the vulnerability of electrical control cabinets to fire. The fuel packages tested were chosen to be representative of small to moderately sized transient trash fuel sources of the type that would be found in a nuclear power plant. The highest fire intensity encountered during these tests was 145 kW. Plume temperatures did not exceed 820/sup 0/C.

Nowlen, S.P.

1986-10-01

101

Compilation of Quality Assurance Documentation for Analyses Performed for the Resumption of Transient Testing Environmental Assessment  

SciTech Connect

This is a companion document to the analyses performed in support of the environmental assessment for the Resumption of Transient Fuels and Materials Testing. It is provided to allow transparency of the supporting calculations. It provides computer code input and output. The basis for the calculations is documented separately in INL (2013) and is referenced, as appropriate. Spreadsheets used to manipulate the code output are not provided.

Annette L. Schafer; A. Jeffrey Sondrup

2013-11-01

102

Single tube hydride heat exchanger test facility  

Microsoft Academic Search

Heat exchanger tests were conducted to develop heat transfer data which would be needed to design a reasonably optimal HYCSOS device. To meet this primary objective, it was necessary to: (1) design and construct a test facility suitable for small scale heat transfer testing; (2) design and construct several representations of proposed HYCSOS heat exchangers; (3) test these designs under

H. P. Egbert; J. S. Horowitz; G. M. Warapius

1979-01-01

103

RAPID Boron-dilution Transient Tests for OECD/CSNI International Standard Problem No. 43  

SciTech Connect

The University of Maryland 2 x 4 Thermalhydraulic Loop Facility (UM 2 x 4 Loop) collected code verification data for rapid boron-dilution (RBD) transients. This paper addresses the objectives of recently completed RBD tests and the redesign of the UM 2 x 4 Loop facility for the four test series of the current program. The UM 2 x 4 Loop facility is described in sufficient detail to permit the preparation of input models for code verification. Initial and boundary conditions are given. The OECD/CSNI International Standard Problem No. 43 (ISP 43) figures of merit for comparison of code predictions to experimental findings are described. Specific values for the most representative figures of merit are given for the two closed test series: injection of a front and injection of a slug without downcomer bypass. Because flow regime is a substantial factor in downcomer mixing for RBD transients, the effect of inertial forces on figures of merit is discussed. Tests with downcomer flowrates that fall below the transition to turbulence are shown to exhibit behaviors different from tests ran at downcomer Reynolds numbers that fall in the turbulent regime. Specifically, it is shown that in high flowrate tests mixing is more vigorous when evaluated from a global perspective, but regions of the slug can remain more segregated from the ambient primary coolant than in slow tests. (authors)

Gavrilas, Mirela [University of Maryland, College Park, MD 20742 (United States); Palazov, Vesselin [ISL Inc., Rockville MD. (United States); Woods, Brian [Dominion Generation, Richmond VA. (United States)

2002-07-01

104

Testing the single-state dominance hypothesis  

SciTech Connect

We present a theoretical analysis of the single-state dominance hypothesis for the two-neutrino double-beta decay process. The theoretical framework is a proton-neutron QRPA based on a deformed Hartree-Fock mean field with BCS pairing correlations. We focus on the decays of {sup 100}Mo, {sup 116}Cd and {sup 128}Te. We do not find clear evidences for single-state dominance within the present approach.

Álvarez-Rodríguez, R. [Universidad Politécnica de Madrid, Avda. Juan Herrera 4, E-28040 Madrid (Spain); Moreno, O.; Moya de Guerra, E. [Universidad Complutense de Madrid, Avda. Complutense, E-28040 Madrid (Spain); Sarriguren, P. [Instituto de Estructura de la Materia (CSIC), Serrano 123, E-28006 Madrid (Spain); Šimkovic, F. [Comenius University, SK-842 15 Bratislava (Slovakia); Faessler, A. [University of Tübingen, D-72076 Tübingen (Germany)

2013-12-30

105

Nonlinear transient wave excitation as a new tool in model testing  

SciTech Connect

Short extension transient waves with tailor-made spectra are extremely efficient for model testing. For small water elevations a linear description of the wave field is satisfactory. With higher transient wave trains, however, the linear description becomes increasingly inaccurate, and a new numerical technique must be developed. Such a new method is based on the fact that short and high wave groups with strong nonlinear characteristics evolve from long and low wave groups, which are characterized by linear principles. As the total energy of the transient wave is invariant during its metamorphosis, the initial linear Fourier spectrum is selected as the backbone of wave information or as the primordial cell from which all nonlinearities are hatched. Based on the initial Fourier spectrum which is the core of the wave information operator the shape variation of the linear transient wave train during propagation is calculated. At selected positions the nonlinear expansion is accomplished by solving the mutually dependent particle motion equations in time domain. The proposed new method uses a numerical nonlinear description of transient wave trains as a function of time or space for any fixed or moving reference point. At its primordial state it is based on a linear superposition of wave information which is complemented by an expanded velocity potential to calculate nonlinear surface elevations, particle motions, velocities, and accelerations. After the nonlinear wave trains converge and pass the concentration point only to diverge and fade away as long, low and linear wave groups, the primordial linear Fourier spectrum can be found again at the end of the development. This step can be used to monitor the transformation. Wave energy spectra and the shape of the wave train can be designed with special regard to the proposed task. Based on these data the entire wave field can be determined.

Clauss, G.F.; Kuehnlein, W.L. [Berlin Univ. of Technology (Germany). Inst. of Naval Architecture and Ocean Engineering

1996-12-31

106

Testing fluvial erosion models using the transient response of bedrock rivers to tectonic forcing in the Apennines, Italy  

E-print Network

Testing fluvial erosion models using the transient response of bedrock rivers to tectonic forcing fluvial erosion models. However, some recent studies of bedrock erosion conclude that transient river long profiles can be approximately characterized by a transportlimited erosion model, while other authors

Cowie, Patience

107

Testing Electronic Devices for Single-Event Upset  

NASA Technical Reports Server (NTRS)

Report prepared describes equipment and summarizes both pretest and onsite procedures for testing of digital electronic devices for susceptibility to single-event upset. Term "single-event upset" denotes variety of temporary or permanent bit flips or latchup induced by single particles of ionizing radiation. Vacuum chamber houses device under test while exposed to ion beam. Vacuum chamber and associated equipment must be brought to ion-beam facility for test.

Nichols, D. K.; Price, W. E.; Malone, C. J.

1986-01-01

108

Hardy-Weinberg Testing of a Single Homozygous Genotype  

Microsoft Academic Search

No proper statistical test is available for the evaluation of deviation of a single homozygous genotype from Hardy-Weinberg equilibrium (HWE) proportion. We propose a 1-d.f. 2 -test. The power of the proposed test is favorable compared to existing HWE testing procedures. The applications of this test are discussed.

John J. Chen; Tao Duan; Richard Single; Kristie Mather; Glenys Thomson

2005-01-01

109

Fabrication and Test of Ferromagnetic Single-Electron-Transistors  

E-print Network

. It provides fast and accurate electrical test results for multiple devices built into standard 16-pad test cages, essentially eliminating the test from the overall processing time. The test system was usedFabrication and Test of Ferromagnetic Single-Electron-Transistors Diploma Thesis Katrin Pappert

Haviland, David

110

A review of experiments and results from the transient reactor test (TREAT) facility.  

SciTech Connect

The TREAT Facility was designed and built in the late 1950s at Argonne National Laboratory to provide a transient reactor for safety experiments on samples of reactor fuels. It first operated in 1959. Throughout its history, experiments conducted in TREAT have been important in establishing the behavior of a wide variety of reactor fuel elements under conditions predicted to occur in reactor accidents ranging from mild off normal transients to hypothetical core disruptive accidents. For much of its history, TREAT was used primarily to test liquid-metal reactor fuel elements, initially for the Experimental Breeder Reactor-II (EBR-II), then for the Fast Flux Test Facility (FFTF), the Clinch River Breeder Reactor Plant (CRBRP), the British Prototype Fast Reactor (PFR), and finally, for the Integral Fast Reactor (IFR). Both oxide and metal elements were tested in dry capsules and in flowing sodium loops. The data obtained were instrumental in establishing the behavior of the fuel under off-normal and accident conditions, a necessary part of the safety analysis of the various reactors. In addition, TREAT was used to test light-water reactor (LWR) elements in a steam environment to obtain fission-product release data under meltdown conditions. Studies are now under way on applications of TREAT to testing of the behavior of high-burnup LWR elements under reactivity-initiated accident (RIA) conditions using a high-pressure water loop.

Deitrich, L. W.

1998-07-28

111

Single event effect test results for candidate spacecraft electronics  

Microsoft Academic Search

We present both heavy ion and proton single event effect (SEE) ground test results for candidate spacecraft electronics. A variety of digital, analog, and fiber optic devices were tested, including DRAMs, FPGAs and fiber links

Kenneth A. Label; Amy K. Moran; Christina M. Seidleck; E. G. Stassinopoulos; J. M. Barth; P. Marshall; M. Carts; C. Marshall; J. Kinnison; B. Carkhuff

1997-01-01

112

Current single event effect test results for candidate spacecraft electronics  

Microsoft Academic Search

We present both proton and heavy ion single event effect (SEE) ground test results for candidate spacecraft electronics. A variety of digital and analog devices were tested, including EEPROMs, DRAMs, and DC-DC converters

Kenneth A. LaBel; Amy K. Moran; Donald K. Hawkins; Anthony B. Sanders; Christina M. Seidleck; Hak S. Kim; James E. Forney; E. G. Stassinopoulos; Paul Marshall; Cheryl Dale; J. Kinnison; B. Carkhuff

1996-01-01

113

Single-shot interferometer: Development and Testing  

E-print Network

· BNL ATF ­ M. Babzien, K. Kusche, R. Malone, V. Yakimenko #12;Outline · Motivation · Concept thick LiTaO3 · Integrated DAQ ­ Tested up to 10Hz operation ­ Possibility to go to 100Hz · Portable #12 manipulations ­ Nondestructive (run parallel with other expt) · CCR ­ Cerenkov radiation from DWA ­ Narrowband

114

Large transient fault current test of an electrical roll ring. [for Space Station Freedom  

NASA Technical Reports Server (NTRS)

The Space Station Freedom uses precision rotary gimbals to provide for sun tracking of its photoelectric arrays. Electrical power, command signals, and data are transferred across the gimbals by roll rings. Roll rings have been shown to be capable of highly efficient electrical transmission and long life, through tests conducted at the NASA Lewis Research Center and Honeywell's Satellite and Space Systems Division in Phoenix, AZ. Large potential fault currents inherent to the power system's DC distribution architecture have brought about the need to evaluate the effects of large transient fault currents on roll rings. A test recently conducted at Lewis subjected a roll ring to a simulated worst case space station electrical fault. The system model used to obtain the fault profile is described, along with details of the reduced order circuit that was used to simulate the fault. Test results comparing roll ring performance before and after the fault are also presented.

Yenni, Edward J.; Birchenough, Arthur G.

1991-01-01

115

Transient high heat load tests on tungsten coating by high-intensity current pulsed electron beam  

NASA Astrophysics Data System (ADS)

Three kinds of tungsten coatings are fabricated by means of APS and CVD, and evaluated by transient high heat load tests by 25 high-intensity current pulsed electron beam pulses with a duration of 0.2 ms and power densities of 0.4, 0.6 and 0.8 GW/m2. Remelting and solidification are found on post-test APS-W coating. However, cracks are developed for the same power densities for the CVD-W coating. APS-W coatings have about 20 times mass loss of CVD-W coating. The mass loss is related to the peak surface temperature of the APS-W coating exceeding the tungsten melting point (3410 °C) during electron beam irradiation. The CVD-W coating during testing was only 1000 °C.

Huang, Jianjun; Zhu, Gengfeng; Wang, Fan; Ru, Lili; Wan, Song; Xiao, Jing; Luo, Guangnan

2014-12-01

116

TRAC-PF1 analysis of LOFT steam-generator feedwater transient test L9-1. [PWR  

SciTech Connect

The Transient Reactor Analysis Code (TRAC-PF1) calculations were compared to test data from Loss-of-Fluid Test (LOFT) L9-1, which was a loss-of-feedwater transient. This paper includes descriptions of the test and the TRAC input and compares the TRAC-calculated results with the test data. We conclude that the code predicted the experiment well, given the uncertainties in the boundary conditions. The analysis indicates the need to model all the flow paths and heat structures, and to improve the TRAC wall condensation heat-transfer model.

Meier, J.K.

1983-01-01

117

Single shaft automotive gas turbine engine characterization test  

NASA Technical Reports Server (NTRS)

An automotive gas turbine incorporating a single stage centrifugal compressor and a single stage radial inflow turbine is described. Among the engine's features is the use of wide range variable geometry at the inlet guide vanes, the compressor diffuser vanes, and the turbine inlet vanes to achieve improved part load fuel economy. The engine was tested to determine its performance in both the variable geometry and equivalent fixed geometry modes. Testing was conducted without the originally designed recuperator. Test results were compared with the predicted performance of the nonrecuperative engine based on existing component rig test maps. Agreement between test results and the computer model was achieved.

Johnson, R. A.

1979-01-01

118

Theoretical Evaluation of the Transient Response of Constant Head and Constant Flow-Rate Permeability Tests  

USGS Publications Warehouse

A theoretical analysis is presented that compares the response characteristics of the constant head and the constant flowrate (flow pump) laboratory techniques for quantifying the hydraulic properties of geologic materials having permeabilities less than 10-10 m/s. Rigorous analytical solutions that describe the transient distributions of hydraulic gradient within a specimen are developed, and equations are derived for each method. Expressions simulating the inflow and outflow rates across the specimen boundaries during a constant-head permeability test are also presented. These solutions illustrate the advantages and disadvantages of each method, including insights into measurement accuracy and the validity of using Darcy's law under certain conditions. The resulting observations offer practical considerations in the selection of an appropriate laboratory test method for the reliable measurement of permeability in low-permeability geologic materials.

Zhang, M.; Takahashi, M.; Morin, R. H.; Esaki, T.

1998-01-01

119

Searches for Radio Pulsars & Fast Transients and Multiwavelength Studies of Single-pulse Emission  

NASA Astrophysics Data System (ADS)

Pulsars are excellent tools for studying a wide array of astrophysical phenomena (e.g. gravitational waves, the interstellar medium, general relativity), yet they are still not fully understood. What are their emission processes and how do they change at different energies? How is giant pulse emission different from regular emission? How are different classes of pulsars (RRATs, magnetars, nulling pulsars, etc.) related? Answering these questions will not only help us to understand pulsars in general, but will also help improve techniques for pulsar searches and timing, gravitational wave searches, and single-pulse searches. The work we present here aims to answer these questions through studies of giant pulse emission, the discovery of new pulsars, and single-pulse studies of a large population of pulsars and RRATs. We took advantage of open telescope time on the 43-m telescope in Green Bank, WV to conduct a long-term study of giant pulses from the Crab pulsar at 1.2 GHz and 330 MHz. Over a timespan of 15 months, we collected a total of 95000 giant pulses which we correlated with both gamma-ray photons from the Fermi satellite and giant pulses collected at 8.9 GHz. Statistics of these pulses show that their amplitudes follow power-law distributions, with indices in the range of 2.1 to 3.1. The correlation with giant pulses at 8.9 GHz showed that the emission processes at 1.2 GHz and 8.9 GHz are related, despite significant profile differences. The correlation with Fermi gamma-ray photons was to test if increased pair production in the magnetosphere was the cause of giant pulses. Our findings suggest that, while it may play a role, increased pair production is not the dominant cause of giant pulses. As part of a single-pulse study, we reprocessed the archival Parkes Multibeam Pulsar Survey, discovering six previously unknown pulsars. PSR J0922-52 has a period of 9.68 ms and a DM of 122.4 pc cm-3. PSR J1147-66 has a period of 3.72 ms and a DM of 133.8 pc cm-3. PSR J1227-6208 has a period of 34.53 ms, a DM of 362.6 pc cm-3, is in a 6.7 day binary orbit. PSR J1546-59 has a period of 7.80 ms and a DM of 168.3 pc cm-3. PSR J1725-3853 is an isolated 4.79-ms pulsar with a DM of 158.2 pc cm-3. PSR J1753-2822 has a period of 18.62 ms, a DM of 298.4 pc cm-3, and is in a 9.3 hour binary orbit. These pulsars were likely missed in earlier processing efforts due to the fact that they have both high DMs and short periods, and also the large number of candidates that needed to be looked through. These discoveries suggest that further pulsars are awaiting discovery in the multibeam survey data. We also searched for single pulses out to a DM of 5000 pc cm-3 with widths of up to two seconds in our reprocessing of the PMPS data. We recorded single pulses from 264 known pulsars and 15 RRATs. We fit amplitude distributions of the pulsars with lognormal distributions and power-law tails, finding that some pulsars show a deviation from a lognormal distribution in the form of an excess of high-energy pulses. Fitting lognormal distributions to the amplitudes of pulses from RRATs showed similar behavior for most RRATs. Here, however, there seem to be two distinct populations of pulses, with the first population being consistent with noise. For pulsars that were detected in a periodicity search, we computed the ratio of their single-pulse S/N to their FFT S/N and looked for correlations between this ratio and physical parameters of the pulsars. We found a few strong correlations, but they all seem to be due to the strongest correlation between the ratio and spin period.

Mickaliger, Mitchell B.

120

High-Speed Single-Event Current Transient Measurements in SiGe HBTs  

NASA Technical Reports Server (NTRS)

Time-resolved ion beam induced charge reveals heavy ion response of IBM 5AM SiGe HBT: 1) Position correlation. 2) Unique response for different bias schemes. 3) Similarities to TPA pulsed-laser data. Heavy ion broad-beam transients provide more realistic device response: 1) Feedback using microbeam data 2) Overcome existing issues of LET and ion range with microbeam Both micro- and broad-beam data sets yield valuable input for TCAD simulations. Uncover detailed mechanisms for SiGe HBTs and other devices fabricated on lightly-doped substrates.

Pellish, Jonathan A.; Reed, R.A.; McMorrow, D.; Vizkelethy, G.; Ferlet-Cavrois, V.; Baggio, J.; Paillet, P.; Duhamel, O.; Phillips, S.D.; Sutton, A.K.; Diestelhorst, R.M.; Cressler, J.D.; Dodd, P.E.; Pate, N.D.; Alles, M.L.; Schrimpf, R.D.; Marshall, P.W.; LaBel, K.A.

2009-01-01

121

TRAC (transient reactor analysis code) analyses of the Savannah River 1985 L-area test series  

SciTech Connect

Thermal-hydraulic analyses of the Savannah River (SR) 1985 L-area AC-process flow tests were performed to benchmark the Los Alamos National Laboratory (LANL) transient reactor analysis code (TRAC) and the TRAC system model of the SR reactors. These analyses are part of LANL's independent safety analysis of the SR reactors. The AC-process flow test series consisted of 11 separate steady-state unpowered tests conducted in the L reactor itself. The tests were performed to provide detailed flow and pressure data for system model benchmarks. The 11 steady-state tests utilized a variety of pump and valve configurations as well as two coolant temperatures. During the tests, pressure data were collected at four locations around each of the six external heat transport loops, at the moderator tank bottom, and at an array of locations in the upper plenum. The 1985 L-Area AC process flow benchmarks demonstrate that TRAC PF1/MOD2-HWR and the Savannah River plant model provide results that are consistent with the available data. In each of the six external loops, the calculated and measured pressures and flows are in reasonable agreement. In the upper plenum, the TRAC results provide an excellent representation of radial and azimuthal variations in pressure.

Elson, J.S.; Lime, J.F. (Los Alamos National Lab., NM (USA))

1990-06-01

122

Implementation details and test results for a transient engine dynamometer and hardware in the loop vehicle model  

Microsoft Academic Search

A state-of-the-art transient dynamometer engine test system has been developed in the Powertrain Control Research Laboratory (PCRL) at the University of Wisconsin-Madison. This system includes a hydrostatic dynamometer capable of excitation in excess of 300 Hz, integrated with a controller running the dynamic driveline equations in real time to calculate the instantaneous engine loads during transients. This hardware-in-the-loop (HIL) virtual

Guy R. Babbitt; John J. Moskwa

1999-01-01

123

IM240 transient I/M dynamometer driving schedule and the composite I/M test procedure  

SciTech Connect

Changes in motor vehicle technology have created the need for more sophisticated Inspection and Maintenance tests. In response to this need, the Environmental Protection Agency Motor Vehicle Emission Laboratory has developed the IM240, a short transient test, as a possible alternative to the current Inspection and Maintenance tests. The EPA Motor Vehicle Emission Laboratory is evaluating the IM240 as well as the CDH-226 and several steady-state tests in the Composite Inspection and Maintenance Test Procedure.

Pidgeon, W.M.; Dobie, N.

1991-01-01

124

Single Event Effects Testing of the Linfinity SG1525A Pulse Width Modulator Controller  

NASA Technical Reports Server (NTRS)

Pulse Width Modulator (PWM) Controllers are the heart of switching power supply systems in development today. The PWMs considered here have the same integration advantages as many other controllers but it also includes the interface drivers for the follow-on power Field Effect Transistors (FET). Previous work on these types of devices looked into the required test methodologies [ 11 and the impact of radiation on the soft start and shutdown circuits of typically incorporated in the technology [2]. Taking advantage of this previous work this study was undertaken to determine the single event destructive and transient susceptibility of the Linfinity SG1525A Pulse Width Modulator Controller. The device was monitored for transient interruptions in the output signals and for destructive events induced by exposing it to a heavy ion beam at the Texas A&M University Cyclotron Single Event Effects Test Facility. After exposing these devices to the beam, a new upset mode has been identified that can lead to catastrophic power supply system failure if this event would occur while drive power FETs off the two device outputs. The devices and the test methods used will be described first. This will be followed by a brief description of the data collected to date (not all data can be presented with the length constraints of the summary) and a summary of the key results.

Howard, J. W., Jr.; Carts, M. A.; LaBel, K. A.; Forney, J. D.; Irwin, T. L.

2003-01-01

125

Published in Ultrafast Phenomena XIII, edited by D. R. Miller et al. (Springer-Verlag, Berlin, 2003), p. 262 Transient Conductivity in Single-Crystal Al2O3  

E-print Network

and the pump-induced change in the THz waveform were recorded. The real and imaginary parts of the transient), p. 262 Transient Conductivity in Single-Crystal Al2O3 Probed by THz Time-Domain Spectroscopy J. Shan of this technique to investigate transient conductivity over a range of temperatures (77K ­ 300K) in single

Heinz, Tony F.

126

Use of ruthenium dyes for subnanosecond detector fidelity testing in real time transient absorption  

NASA Astrophysics Data System (ADS)

Transient absorption spectroscopy is a powerful tool for the study of photoreactions on time scales from femtoseconds to seconds. Typically, reactions slower than ˜1 ns are recorded by the "classical" technique; the reaction is triggered by an excitation flash, and absorption changes accompanying the reaction are recorded in real time using a continuous monitoring light beam and a detection system with sufficiently fast response. The pico- and femtosecond region can be accessed by the more recent "pump-probe" technique, which circumvents the difficulties of real time detection on a subnanosecond time scale. This is paid for by accumulation of an excessively large number of shots to sample the reaction kinetics. Hence, it is of interest to extend the classical real time technique as far as possible to the subnanosecond range. In order to identify and minimize detection artifacts common on a subnanosecond scale, like overshoot, ringing, and signal reflections, rigorous testing is required of how the detection system responds to fast changes of the monitoring light intensity. Here, we introduce a novel method to create standard signals for detector fidelity testing on a time scale from a few picoseconds to tens of nanoseconds. The signals result from polarized measurements of absorption changes upon excitation of ruthenium complexes {[Ru(bpy)3]2+ and a less symmetric derivative} by a short laser flash. Two types of signals can be created depending on the polarization of the monitoring light with respect to that of the excitation flash: a fast steplike bleaching at magic angle and a monoexponentially decaying bleaching for parallel polarizations. The lifetime of the decay can be easily varied via temperature and viscosity of the solvent. The method is applied to test the performance of a newly developed real time transient absorption setup with 300 ps time resolution and high sensitivity.

Byrdin, Martin; Thiagarajan, Viruthachalam; Villette, Sandrine; Espagne, Agathe; Brettel, Klaus

2009-04-01

127

Use of ruthenium dyes for subnanosecond detector fidelity testing in real time transient absorption  

SciTech Connect

Transient absorption spectroscopy is a powerful tool for the study of photoreactions on time scales from femtoseconds to seconds. Typically, reactions slower than {approx}1 ns are recorded by the ''classical'' technique; the reaction is triggered by an excitation flash, and absorption changes accompanying the reaction are recorded in real time using a continuous monitoring light beam and a detection system with sufficiently fast response. The pico- and femtosecond region can be accessed by the more recent ''pump-probe'' technique, which circumvents the difficulties of real time detection on a subnanosecond time scale. This is paid for by accumulation of an excessively large number of shots to sample the reaction kinetics. Hence, it is of interest to extend the classical real time technique as far as possible to the subnanosecond range. In order to identify and minimize detection artifacts common on a subnanosecond scale, like overshoot, ringing, and signal reflections, rigorous testing is required of how the detection system responds to fast changes of the monitoring light intensity. Here, we introduce a novel method to create standard signals for detector fidelity testing on a time scale from a few picoseconds to tens of nanoseconds. The signals result from polarized measurements of absorption changes upon excitation of ruthenium complexes {l_brace}[Ru(bpy){sub 3}]{sup 2+} and a less symmetric derivative{r_brace} by a short laser flash. Two types of signals can be created depending on the polarization of the monitoring light with respect to that of the excitation flash: a fast steplike bleaching at magic angle and a monoexponentially decaying bleaching for parallel polarizations. The lifetime of the decay can be easily varied via temperature and viscosity of the solvent. The method is applied to test the performance of a newly developed real time transient absorption setup with 300 ps time resolution and high sensitivity.

Byrdin, Martin; Thiagarajan, Viruthachalam; Villette, Sandrine; Espagne, Agathe; Brettel, Klaus [CEA, IBITECS, Laboratoire de Photocatalyse et Biohydrogene, F-91191 Gif-sur-Yvette, France and CNRS, URA 2096, F-91191 Gif-sur-Yvette (France)

2009-04-15

128

Photo-induced current transient spectroscopy of single crystal Tl6I4Se  

NASA Astrophysics Data System (ADS)

The compound Tl6I4Se is a promising wide band gap semiconductor for hard radiation detection at room temperature. To further improve its detection efficiency, native defects have been investigated using photo-induced current transient spectroscopy (PICTS). We observe two shallow acceptor levels with mean activation energies of 76, 175 meV, and two shallow donor defects 62, and 96 meV, respectively. No deeper donor levels are observed. The levels are attributed to native point defects. Defect capture cross sections in the range 10-21 to 10-18 cm2 were measured. The small capture cross sections are attributed to the effective screening of the defects due to a large static dielectric constant.

Liu, Z.; Peters, J. A.; Sebastian, M.; Kanatzidis, M. G.; Im, J.; Freeman, A. J.; Wessels, B. W.

2014-11-01

129

Particle Tracking-Based Strategies For Simulating Transport in a Transient Groundwater Flow Field at Yucca Flat, Nevada Test Site, USA  

NASA Astrophysics Data System (ADS)

Developing probabilistic-based calculations of contaminant concentrations over the next 1000 years at Yucca Flat, Nevada Test site, require tremendous computational effort in this highly complex hydrogeologic surface environment. The sources of contamination, underground nuclear tests conducted between 1951 and 1992, not only released radionuclides to the subsurface but also created abrupt, significant changes in rock properties and caused large transients in the measured hydraulic gradients. To efficiently model contaminant migration from these sources we use a particle-based approach within a transient flow field. Here, we present results using two methods; first, an explicit representation of time-varying sources using large numbers of particles introduced at source-specific rates over time, each representing a unique mass of solute. This method provides good results, but is computationally expensive since sensitivity to uncertainty in source term and transport parameters can only be explored with discrete process-model runs. The second method employs a convolution method (PLUMECALC) which can efficiently consider a large number of variations in the source terms and in certain transport parameters with a single process-model run. Implementation of this second approach required extension of the existing methodology to conditions of transient flow. We find very good comparison between the two methods on small test problems and excellent computational advantages when applying the convolution method in the NTS application

Keating, E. H.; Srinivasan, G.; Kang, Q.; Li, C.; Dash, Z.; Kwicklis, E. M.

2009-12-01

130

TREAT (Transient Reactor Test Facility) reactor control rod scram system simulations and testing  

SciTech Connect

Air cylinders moving heavy components (100 to 300 lbs) at high speeds (above 300 in/sec) present a formidable end-cushion-shock problem. With no speed control, the moving components can reach over 600 in/sec if the air cylinder has a 5 ft stroke. This paper presents an overview of a successful upgrade modification to an existing reactor control rod drive design using a computer model to simulate the modified system performance for system design analysis. This design uses a high speed air cylinder to rapidly insert control rods (278 lb moved 5 ft in less than 300 msec) to scram an air-cooled test reactor. Included is information about the computer models developed to simulate high-speed air cylinder operation and a unique new speed control and end cushion design. A patent application is pending with the US Patent Trade Mark Office for this system (DOE case number S-68,622). The evolution of the design, from computer simulations thru operational testing in a test stand (simulating in-reactor operating conditions) to installation and use in the reactor, is also described. 6 figs.

Solbrig, C.W.; Stevens, W.W.

1990-01-01

131

Single-inductor, multiple-output buck converter with parallel source transient recovery  

E-print Network

To address the need for multiple regulated voltage supplies in electronic devices, this thesis presents a modeling and design study of a single-inductor, multiple-output (SIMO) DC-DC buck converter with parallel source ...

King, Charles Jackson, III

2009-01-01

132

Transient Plume Model Testing Using LADEE Spacecraft Attitude Control System Operations  

NASA Technical Reports Server (NTRS)

The Lunar Atmosphere Dust Environment Explorer (LADEE) spacecraft is being designed for a mission featuring low altitude orbits of the Moon to take relevant ambient measurements before that environment becomes altered by future exploration activities. Instruments include a neutral mass spectrometer capable of measuring ambient species density levels below 100 molecules/cu cm. Coincidentally, with a favorable combination of spacecraft orientations, it is also possible to measure plume gases from LADEE attitude control system thruster operations as they are reflected from the daytime lunar surface and subsequently intercepted by the spacecraft as it orbits overhead. Under such circumstances, it may be possible to test a variety of properties and assumptions associated with various transient plume models or to infer certain aspects regarding lunar surface properties.

Woronowicz, M. S.

2010-01-01

133

Measuring the Optical Performance of Evacuated Receivers via an Outdoor Thermal Transient Test: Preprint  

SciTech Connect

Modern parabolic trough solar collectors operated at high temperatures to provide the heat input to Rankine steam power cycles employ evacuated receiver tubes along the collector focal line. High performance is achieved via the use of a selective surface with a high absorptance for incoming short-wave solar radiation and a low emittance for outgoing long-wave infrared radiation, as well as the use of a hard vacuum to essentially eliminate convective and conductive heat losses. This paper describes a new method that determines receiver overall optical efficiency by exposing a fluid-filled, pre-cooled receiver to one sun outdoors and measuring the slope of the temperature curve at the point where the receiver temperature passes the glass envelope temperature (that is, the point at which there is no heat gain or loss from the absorber). This transient test method offers the potential advantages of simplicity, high accuracy, and the use of the actual solar spectrum.

Kutscher, C.; Burkholder, F.; Netter, J.

2011-08-01

134

Heat and Mass Transfer Analysis of Dehumidifiers Using Adiabatic Transient Tests  

SciTech Connect

Adiabatic step transient data were obtained for two dehumidifier test matrices, using parallel plates with crushed silica gel and staggered parallel strips coated with microbead silica gel. The data were analyzed using the statistical moments method and combined heat and mass transfer analogy theory. The analysis showed that the average overall Nusselt number in both matrices was about 40% to 50% lower than laminar flow predictions. The average overall Nusselt number for the microbead staggered matrix was about 85% larger than that of the crushed silica-gel parallel-plate matrix. The Nusselt number/friction factor Reynolds number ratio (Nu/fRe) of the microbead, staggered parallel-strip matrix was about 28% larger than that of the crushed silica-gel parallel-plate matrix. These results were explained by the presence of a stagnant gas film. The results showed that compact, high-performance, rotary dehumidifiers for desiccant cooling systems are possible and economical.

Maclaine-Cross, I. L.; Pesaran, A. A.

1986-04-01

135

Experimental test of nonclassicality for a single particle  

E-print Network

In a recent paper [R. Alicki and N. Van Ryn, J. Phys. A: Math. Theor., 41, 062001 (2008)] a test of nonclassicality for a single qubit was proposed. Here, we discuss the class of local realistic theories to which this test applies and present an experimental realization.

G. Brida; I. Degiovanni; M. Genovese; V. Schettini; S. Polyakov; A. Migdall

2008-04-10

136

Selective isolation of transiently transfected cells from a mammalian cell population with vectors expressing a membrane anchored single-chain antibody  

Microsoft Academic Search

We present here a novel technology for the rapid selection of transiently transfected cells from total populations in culture. This system utilizes recombinant antibody technology to produce a ‘molecular hook’ by displaying a hapten-binding single-chain antibody (sFv) on the surface of transfected cells. Mammalian cell lines from several origins were transiently transfected with a plasmid (pHook-1) that encodes an sFv

Jonathan D. Chesnut; Apollo R. Baytan; Marijane Russell; Mei-Ping Chang; Amy Bernard; Ian H. Maxwell; James P. Hoeffler

1996-01-01

137

Impacts Analyses Supporting the National Environmental Policy Act Environmental Assessment for the Resumption of Transient Testing Program  

SciTech Connect

Environmental and health impacts are presented for activities associated with transient testing of nuclear fuel and material using two candidate test reactors. Transient testing involves irradiation of nuclear fuel or materials for short time-periods under high neutron flux rates. The transient testing process includes transportation of nuclear fuel or materials inside a robust shipping cask to a hot cell, removal from the shipping cask, pre-irradiation examination of the nuclear materials, assembly of an experiment assembly, transportation of the experiment assembly to the test reactor, irradiation in the test reactor, transport back to the hot cell, and post-irradiation examination of the nuclear fuel or material. The potential for environmental or health consequences during the transportation, examination, and irradiation actions are assessed for normal operations, off-normal (accident) scenarios, and transportation. Impacts to the environment (air, soil, and groundwater), are assessed during each phase of the transient testing process. This report documents the evaluation of potential consequences to the general public. This document supports the Environmental Assessment (EA) required by the U.S. National Environmental Policy Act (NEPA) (42 USC Subsection 4321 et seq.).

Annette L. Schafer; Lloyd C. Brown; David C. Carathers; Boyd D. Christensen; James J. Dahl; Mark L. Miller; Cathy Ottinger Farnum; Steven Peterson; A. Jeffrey Sondrup; Peter V. Subaiya; Daniel M. Wachs; Ruth F. Weiner

2013-11-01

138

Heavy ion induced Single Event Phenomena (SEP) data for semiconductor devices from engineering testing  

NASA Technical Reports Server (NTRS)

The accumulation of JPL data on Single Event Phenomena (SEP), from 1979 to August 1986, is presented in full report format. It is expected that every two years a supplement report will be issued for the follow-on period. This data for 135 devices expands on the abbreviated test data presented as part of Refs. (1) and (3) by including figures of Single Event Upset (SEU) cross sections as a function of beam Linear Energy Transfer (LET) when available. It also includes some of the data complied in the JPL computer in RADATA and the SPACERAD data bank. This volume encompasses bipolar and MOS (CMOS and MHNOS) device data as two broad categories for both upsets (bit-flips) and latchup. It also includes comments on less well known phenomena, such as transient upsets and permanent damage modes.

Nichols, Donald K.; Huebner, Mark A.; Price, William E.; Smith, L. S.; Coss, James R.

1988-01-01

139

Development of single fluid volume element method for simulation of transient fluid flow in self-siphons  

NASA Astrophysics Data System (ADS)

A simple model for transient flow in a narrow pipe is presented in this work. The model is simply derived from Newton's second law of motion. As an example it is used to predict flow occurrence in two forms of self-siphon, which are inverted-U and M-like forms. Simulation for system consists only a vertical pipe is also presented since it is actually part of the both siphon systems. For the simple systems the model can have good predictions but for the complex system it can only have 89.6 % good prediction. Its simplicity can be used to illustrate how the interface between fluid and air, single fluid volume element (SFVE) moves along the siphon. The method itself is named as SFVE method.

Viridi, S.; Novitrian, Nurhayati, Hidayat, W.; Latief, F. D. E.; Zen, F. P.

2014-09-01

140

COMMIX-1AR/P: A three-dimensional transient single-phase computer program for thermal hydraulic analysis of single and multicomponent systems  

SciTech Connect

The COMMIX-LAR/P computer program is designed for analyzing the steady-state and transient aspects of single-phase fluid flow and heat transfer in three spatial dimensions. This version is an extension of the modeling in COMMIX-lA to include multiple fluids in physically separate regions of the computational domain, modeling descriptions for pumps, radiation heat transfer between surfaces of the solids which are embedded in or surround the fluid, a keg model for fluid turbulence, and improved numerical techniques. The porous-medium formulation in COMMIX allows the program to be applied to a wide range of problems involving both simple and complex geometrical arrangements. The internal aspects of the COMMIX-LAR/P program are presented, covering descriptions of subprograms, variables, and files.

Garner, P.L.; Blomquist, R.N.; Gelbard, E.M.

1992-09-01

141

COMMIX-1AR/P: A three-dimensional transient single-phase computer program for thermal hydraulic analysis of single and multicomponent systems  

SciTech Connect

The COMMIX-1AR/P computer program is designed for analyzing the steady-state and transient aspects of single-phase fluid flow and heat transfer in three spatial dimensions. This version is an extension of the modeling in COMMIX-1A to include multiple fluids in physically separate regions of the computational domain, modeling descriptions for pumps, radiation heat transfer between surfaces of the solids which are embedded in or surround the fluid, a k-[var epsilon] model for fluid turbulence, and improved numerical techniques. The porous-medium formulation in COMMIX allows the program to be applied to a wide range of problems involving both simple and complex geometrical arrangements. The input preparation and execution procedures are presented for the COMMIX-1AR/P program and several postprocessor programs which produce graphical displays of the calculated results.

Garner, P.L.; Blomquist, R.N.; Gelbard, E.M.

1992-09-01

142

Analysis of Transient Behavior of a Single-Phase Self-Regulated Self-Excited Induction Generator using a Three-Phase Machine  

Microsoft Academic Search

This paper presents the analysis of transient behavior of a single-phase self-excited induction generator (SEIG) using a three-phase induction machine feeding single-phase inductive load. This scheme has improved voltage regulation. Moreover, since a star-connected stator winding is employed, the waveform of the output voltage becomes sinusoidal. The dynamic model of a single-phase SEIG is developed based on stationary reference frame

S. N. Mahato; M. P. Sharma; S. P. Singh

2006-01-01

143

Information-gap robustness for the test analysis correlation of nonlinear transient simulation  

SciTech Connect

An alternative to the theory of probability is applied to the problem of assessing the robustness of test-analysis correlation to parametric sources of uncertainty. The analysis technique is based on the theory of information-gap, which models the clustering of uncertain events in families of nested sets instead of assuming a probability structure. The system investigated is the propagation of a transient impact through a layer of hyper-elastic material. The two sources of non-linearity are the softening of the constitutive law implemented to model the hyper-elastic material and contact dynamics at the interface between metallic and crushable materials. The robustness of test-analysis correlation to sources of parametric variability is first studied to identify the parameters of the model that significantly influence the agreement between measurements and predictions. Calibration under non-probabilistic uncertainty is then illustrated. Finally, two information-gap models of uncertainty are embedded to represent uncertainty not only in the knowledge of the model's parameters but also in the form of the model itself. Although computationally expensive, it is demonstrated that the information-gap reasoning can greatly enhance our understanding of a moderately complex system when the theory of probability cannot be applied due to insufficient information.

Hemez, F. M. (François M.); Ben-Haim, Yakov,; Cogan, S. (Scott)

2002-01-01

144

Fast & accurate algorithm for jitter test with a single frequency test signal  

Microsoft Academic Search

A fast and accurate algorithm for jitter test is presented. The proposed method uses a single test with a high frequency input sine wave. Elimination of the need of a 2nd low frequency test required in the IEEE standard test offers significant savings on both hardware and data acquisition time. The new method is computationally efficient since it requires only

Minshun Wu; Degang Chen; Jingbo Duan

2011-01-01

145

Calcium transient and its propagation by poking a single human microvascular endothelial cell with a heat-blunt-ended micropipette  

Microsoft Academic Search

In order to elucidate signal transduction mechanism on how cells sense mechanical deformation, cytosolic Ca transients, by poking with a heat-blunted glass micropipette, were directly observed in human microvascular endothelial cell (HMEC). Cytosolic Ca transients were observed in almost all the HMECs poked with a micropipette. The transients started at the point of poking, and propagated at the peripheral regions

Takashi Ushida; Norihiko Yoshizawa; Takuya Noguchi; Tetsuya Tateishi

2001-01-01

146

Calcium transients during early development in single starfish (Asterias forbesi) oocytes  

SciTech Connect

Maturation and fertilization of the starfish oocyte are putative calcium-dependent events. The authors have investigated the spatial distribution and temporal dynamics of this calcium dependence in single oocytes of Asterias forbesi. They used the calcium photoprotein, aequorin, in conjunction with a microscope-photomultiplier and microscope-image intensifier. Surprisingly, in contrast to earlier work with Marasthenias glacialis, there is no detectable increase in intracellular-free calcium in the oocyte of A. forbesi in response to the maturation hormone 1-methyl adenine. During fertilization of the same, matured, A. forbesi oocyte there is a large increase in intracellular-free calcium. The calcium concentration increases to approx.1 ..mu..M at the point of insemination and the region of elevated free calcium expands across the oocyte in approx.20 s (17-19/sup 0/C). After the entire oocyte reaches an elevated concentration of free calcium, the concentration decreases uniformly throughout the oocyte over the next several minutes.

Eisen, A.; Reynolds, G.T.

1984-11-01

147

Pre-flight transient dynamic analysis of B-52 carrying Space Shuttle solid rocket booster drop-test vehicle  

NASA Technical Reports Server (NTRS)

This paper concerns the transient dynamic analysis of the B-52 aircraft carrying the Space Shuttle solid-rocket booster drop-test vehicle (SRB/DTV). The NASA structural analysis (NASTRAN) finite-element computer program was used in the analysis. The B-52 operating conditions considered for analysis were (1) landing and (2) braking on aborted takeoff runs. The transient loads for the B-52 pylon front and rear hooks were calculated. The results can be used to establish the safe maneuver envelopes for the B-52 carrying the SRB/DTV in landings and brakings.

Ko, W. L.; Schuster, L. S.

1983-01-01

148

Preflight transient dynamic analyses of B-52 aircraft carrying Space Shuttle solid rocket booster drop-test vehicle  

NASA Technical Reports Server (NTRS)

This paper concerns the transient dynamic analysis of the B-52 aircraft carrying the Space Shuttle solid rocket booster drop test vehicle (SRB/DTV). The NASA structural analysis (NASTRAN) finite element computer program was used in the analysis. The B-52 operating conditions considered for analysis were (1) landing and (2) braking on aborted takeoff runs. The transient loads for the B-52 pylon front and rear hooks were calculated. The results can be used to establish the safe maneuver envelopes for the B-52 carrying the SRB/DTV in landings and brakings.

Ko, W. L.; Schuster, L. S.

1984-01-01

149

Experimental data report for transient flow calibration facility tests IIIA101, IIIA102, IIIA201, and IIIA202  

Microsoft Academic Search

Thermal-hydraulic response data are presented for the transient performance tests of an ECC pitot tube rake (IIIA201, IIIA202) and both an ECC pitot tube rake and modular drag disc-turbine transducer (DTT) rake (IIIA101, IIIA102). The tests were conducted in a system which provided full scale simulation of the pressure vessel and intact loop cold leg piping of the Loss of

Wambach

1980-01-01

150

Measurement of transient acoustic fields using a single-shot pressure-sensitive paint system  

NASA Astrophysics Data System (ADS)

A pressure-sensitive paint (PSP) system capable of measuring high-frequency acoustic fields with non-periodic, acoustic-level pressure changes is described. As an optical measurement technique, PSP provides the experimenter with a global distribution of pressure on a painted surface. To demonstrate frequency response and enhanced sensitivity to pressure changes, a PSP system consisting of a polymer/ceramic matrix binder with platinum tetra(pentafluorophenyl) porphyrin (PtTFPP) as the oxygen probe was applied to a wall inside an acoustic resonance cavity excited at 1.3 kHz. A data acquisition technique based on the luminescent decay lifetime of the oxygen sensors excited by a single pulse of light afforded the ability to capture instantaneous pressure fields with no phase-averaging. Superimposed wave-like structures were observed with a wavelength corresponding to a 4.7% difference from the theoretical value for a sound wave emanating from the speaker. High sound pressure cases upwards of 145 dB (re 20 ?Pa) exhibited skewed nodal lines attributed to a nonlinear acoustic field. The lowest sound pressure level of 125.4 dB—corresponding to an amplitude of 52.7 Pa, or approximately 0.05% of standard sea-level atmospheric pressure—showed that the paint could resolve the spatial details of the mode shape at the given resonance condition.

Disotell, Kevin J.; Gregory, James W.

2011-07-01

151

Transient and Steady-state Tests of the Space Power Research Engine with Resistive and Motor Loads  

NASA Technical Reports Server (NTRS)

The NASA Lewis Research Center (LeRC) has been testing free-piston Stirling engine/linear alternators (FPSE/LA) to develop advanced power convertors for space-based electrical power generation. Tests reported herein were performed to evaluate the interaction and transient behavior of FPSE/LA-based power systems with typical user loads. Both resistive and small induction motor loads were tested with the space power research engine (SPRE) power system. Tests showed that the control system could maintain constant long term voltage and stable periodic operation over a large range of engine operating parameters and loads. Modest resistive load changes were shown to cause relatively large voltage and, therefore, piston and displacer amplitude excursions. Starting a typical small induction motor was shown to cause large and, in some cases, deleterious voltage transients. The tests identified the need for more effective controls, if FPSE/LAs are to be used for stand-alone power systems. The tests also generated a large body of transient dynamic data useful for analysis code validation.

Rauch, Jeffrey S.; Kankam, M. David

1995-01-01

152

Transient potentiation of spontaneous EPSPs in rat mossy cells induced by depolarization of a single neurone.  

PubMed Central

1. The amplitude and frequency of spontaneously occurring EPSPs recorded intracellularly in rat mossy cells was estimated by measuring membrane potential variance in short segments of a continuous voltage record. Changes in variance reflected changes in the amplitude and/or the frequency of spontaneous EPSPs. 2. Short trains of depolarizing current pulses evoked a delayed increase in membrane potential variance in 55% of trials. Variance increased by 487% during these responses and remained elevated for 124 +/- 16 s. Increases in variance were not associated with large changes in the intrinsic properties of the mossy cell such as resting membrane potential and input resistance. We termed this phenomenon depolarization-related potentiation (DRP). 3. Epochs of elevated variance were associated with an increase in both the average amplitude and frequency of spontaneous EPSPs. During the peak of the response, the mean interval between spontaneous EPSPs decreased by 36.8%. Computer-generated voltage records with randomly distributed EPSP amplitudes and inter-EPSP intervals suggested that this decrease in inter-EPSP intervals was not sufficient to account for the magnitude of the variance increase observed. Based on this model, we estimated that a 90% increase in the average amplitude of spontaneous EPSPs, in addition to the experimentally measured decrease in the average inter-EPSP interval, was required to reproduce the magnitude of the change in variance observed. In the potentiated state, the amplitude of spontaneous EPSPs often exceeded 10 mV. 4. We also observed epochs of increased variance that occurred spontaneously. These spontaneous epochs closely resembled epochs evoked by depolarizing stimuli, suggesting that the stimulus was acting as a trigger for a spontaneously occurring behaviour. Additional evidence supporting this hypothesis was provided by the observation that stereotyped patterns of increased variance could be evoked by brief stimuli, such as a single 5 s depolarizing step. Dual intracellular recordings from two mossy cells demonstrated that spontaneous epochs of increased variance occurred independently in different neurones. This result makes it unlikely that these variance increases were due to a global change in the slice environment such as a propagating wave of potassium ions. 5. Bath application of the Na+ channel blocker TTX eliminated most, but not all, of the normal on-going spontaneous EPSPs in mossy cells. Treatment with depolarizing current pulses was effective in potentiating TTX-resistant spontaneous EPSPs in three of seven trials. Potentiation also decreased the mean interval between TTX-resistant miniature EPSPs (by an average of 66.9%) in two trials examined. 6. These results suggest that DRP results from the activation of an intrinsic phenomenon within the dentate gyrus by strong depolarization of a single mossy cell. Our data suggest that several mechanisms are involved in the expression of DRP since changes in EPSP amplitude and frequency can occur with varying delays from the stimulus. The ability of depolarizing current pulses to potentiate TTX-resistant miniature EPSPs suggests that at least one component of this plasticity occurs at the granule cell-mossy cell synapse. PMID:8842007

Strowbridge, B W; Schwartzkroin, P A

1996-01-01

153

System level latchup mitigation for single event and transient radiation effects on electronics  

SciTech Connect

A `blink` technique, analogous to a person blinking at a flash of bright light, is provided for mitigating the effects of single event current latchup and prompt pulse destructive radiation on a micro-electronic circuit. The system includes event detection means, power dump logic means, and energy limiting measures with autonomous recovery. The event detection means includes ionizing radiation pulse detection means for detecting a pulse of ionizing radiation and for providing at an output terminal thereof a detection signal indicative of the detection of a pulse of ionizing radiation or by ion-induced destructive latchup of a semiconductor device. The current sensing means is coupled to the power bus for determining an occurrence of excess current through the power bus caused by ionizing radiation. The power dump means includes power dump logic means having a first input terminal connected to the output terminal of the ionizing radiation pulse detection means and having a second input terminal connected to the output terminal of the current sensing means. The power dump logic means provides an output signal to the input terminal of the means for opening the power bus and the means for shorting the power bus to a ground potential to remove power from the power bus. The energy limiting mean with autonomous recovery includes means for opening the power bus and means for shorting the power bus to a ground potential. The means for opening the power bus and means for shorting the power bus to a ground potential includes a series FET and a shunt FET. The invention provides for self-contained sensing for latchup, first removal of power to protect latched components, and autonomous recovery to enable transparent operation of other system elements.

Kimbrough, J.R.; Colella, N.J.

1994-12-31

154

System level latchup mitigation for single event and transient radiation effects on electronics  

DOEpatents

A ``blink`` technique, analogous to a person blinking at a flash of bright light, is provided for mitigating the effects of single event current latchup and prompt pulse destructive radiation on a micro-electronic circuit. The system includes event detection circuitry, power dump logic circuitry, and energy limiting measures with autonomous recovery. The event detection circuitry includes ionizing radiation pulse detection means for detecting a pulse of ionizing radiation and for providing at an output terminal thereof a detection signal indicative of the detection of a pulse of ionizing radiation. The current sensing circuitry is coupled to the power bus for determining an occurrence of excess current through the power bus caused by ionizing radiation or by ion-induced destructive latchup of a semiconductor device. The power dump circuitry includes power dump logic circuitry having a first input terminal connected to the output terminal of the ionizing radiation pulse detection circuitry and having a second input terminal connected to the output terminal of the current sensing circuitry. The power dump logic circuitry provides an output signal to the input terminal of the circuitry for opening the power bus and the circuitry for shorting the power bus to a ground potential to remove power from the power bus. The energy limiting circuitry with autonomous recovery includes circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential. The circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential includes a series FET and a shunt FET. The invention provides for self-contained sensing for latchup, first removal of power to protect latched components, and autonomous recovery to enable transparent operation of other system elements. 18 figs.

Kimbrough, J.R.; Colella, N.J.

1997-09-30

155

System level latchup mitigation for single event and transient radiation effects on electronics  

DOEpatents

A "blink" technique, analogous to a person blinking at a flash of bright light, is provided for mitigating the effects of single event current latchup and prompt pulse destructive radiation on a micro-electronic circuit. The system includes event detection circuitry, power dump logic circuitry, and energy limiting measures with autonomous recovery. The event detection circuitry includes ionizing radiation pulse detection means for detecting a pulse of ionizing radiation and for providing at an output terminal thereof a detection signal indicative of the detection of a pulse of ionizing radiation. The current sensing circuitry is coupled to the power bus for determining an occurrence of excess current through the power bus caused by ionizing radiation or by ion-induced destructive latchup of a semiconductor device. The power dump circuitry includes power dump logic circuitry having a first input terminal connected to the output terminal of the ionizing radiation pulse detection circuitry and having a second input terminal connected to the output terminal of the current sensing circuitry. The power dump logic circuitry provides an output signal to the input terminal of the circuitry for opening the power bus and the circuitry for shorting the power bus to a ground potential to remove power from the power bus. The energy limiting circuitry with autonomous recovery includes circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential. The circuitry for opening the power bus and circuitry for shorting the power bus to a ground potential includes a series FET and a shunt FET. The invention provides for self-contained sensing for latchup, first removal of power to protect latched components, and autonomous recovery to enable transparent operation of other system elements.

Kimbrough, Joseph Robert (Pleasanton, CA); Colella, Nicholas John (Livermore, CA)

1997-01-01

156

Pressure transient test analysis of vuggy naturally fractured carbonate reservoir: field case study  

E-print Network

is to analyze, interpret and categorize the pressure transient responses obtained from 22 wells in a vuggy naturally fractured carbonate reservoir in an attempt to understand the heterogeneities of the porosity system. Different modeling techniques useful...

Ajayi, Babatunde Tolulope

2009-06-02

157

FOREVER ALONE? TESTING SINGLE ECCENTRIC PLANETARY SYSTEMS FOR MULTIPLE COMPANIONS  

SciTech Connect

Determining the orbital eccentricity of an extrasolar planet is critically important for understanding the system's dynamical environment and history. However, eccentricity is often poorly determined or entirely mischaracterized due to poor observational sampling, low signal-to-noise, and/or degeneracies with other planetary signals. Some systems previously thought to contain a single, moderate-eccentricity planet have been shown, after further monitoring, to host two planets on nearly circular orbits. We investigate published apparent single-planet systems to see if the available data can be better fit by two lower-eccentricity planets. We identify nine promising candidate systems and perform detailed dynamical tests to confirm the stability of the potential new multiple-planet systems. Finally, we compare the expected orbits of the single- and double-planet scenarios to better inform future observations of these interesting systems.

Wittenmyer, Robert A.; Horner, Jonathan; Tinney, C. G.; Bailey, J.; Salter, G. S.; Wright, D. [Department of Astrophysics, School of Physics, Faculty of Science, The University of New South Wales, Sydney, NSW 2052 (Australia); Wang Songhu; Zhou Jilin [Department of Astronomy and Key Laboratory of Modern Astronomy and Astrophysics in Ministry of Education, Nanjing University, Nanjing 210093 (China); Butler, R. P. [Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road, NW, Washington, DC 20015-1305 (United States); Jones, H. R. A. [University of Hertfordshire, Centre for Astrophysics Research, Science and Technology Research Institute, College Lane, AL10 9AB Hatfield (United Kingdom); O'Toole, S. J. [Australian Astronomical Observatory, P.O. Box 915, North Ryde, NSW 1670 (Australia); Carter, B. D., E-mail: rob@phys.unsw.edu.au [Faculty of Sciences, University of Southern Queensland, Toowoomba, Queensland 4350 (Australia)

2013-09-15

158

An entropy test for single-locus genetic association analysis  

PubMed Central

Background The etiology of complex diseases is due to the combination of genetic and environmental factors, usually many of them, and each with a small effect. The identification of these small-effect contributing factors is still a demanding task. Clearly, there is a need for more powerful tests of genetic association, and especially for the identification of rare effects Results We introduce a new genetic association test based on symbolic dynamics and symbolic entropy. Using a freely available software, we have applied this entropy test, and a conventional test, to simulated and real datasets, to illustrate the method and estimate type I error and power. We have also compared this new entropy test to the Fisher exact test for assessment of association with low-frequency SNPs. The entropy test is generally more powerful than the conventional test, and can be significantly more powerful when the genotypic test is applied to low allele-frequency markers. We have also shown that both the Fisher and Entropy methods are optimal to test for association with low-frequency SNPs (MAF around 1-5%), and both are conservative for very rare SNPs (MAF<1%) Conclusions We have developed a new, simple, consistent and powerful test to detect genetic association of biallelic/SNP markers in case-control data, by using symbolic dynamics and symbolic entropy as a measure of gene dependence. We also provide a standard asymptotic distribution of this test statistic. Given that the test is based on entropy measures, it avoids smoothed nonparametric estimation. The entropy test is generally as good or even more powerful than the conventional and Fisher tests. Furthermore, the entropy test is more computationally efficient than the Fisher's Exact test, especially for large number of markers. Therefore, this entropy-based test has the advantage of being optimal for most SNPs, regardless of their allele frequency (Minor Allele Frequency (MAF) between 1-50%). This property is quite beneficial, since many researchers tend to discard low allele-frequency SNPs from their analysis. Now they can apply the same statistical test of association to all SNPs in a single analysis., which can be especially helpful to detect rare effects. PMID:20331859

2010-01-01

159

Experimental data report for transient flow calibration facility tests IIIA101, IIIA102, IIIA201, and IIIA202  

SciTech Connect

Thermal-hydraulic response data are presented for the transient performance tests of an ECC pitot tube rake (IIIA201, IIIA202) and both an ECC pitot tube rake and modular drag disc-turbine transducer (DTT) rake (IIIA101, IIIA102). The tests were conducted in a system which provided full scale simulation of the pressure vessel and intact loop cold leg piping of the Loss of Fluid Test Facility (LOFT). A load cell system was used to provide a reference mass flow rate measurement.

Wambach, J.L.

1980-03-26

160

Novel board level drop test simulation using implicit transient analysis with input-G method  

Microsoft Academic Search

In recent several years, there are many efforts to study the reliability performance of IC package under drop impact loading by numerical modeling. Most of the models utilize LS-DYNA or ABAQUS types of explicit solvers. However, there is a lack of efficient implicit model for the organization without access to explicit solvers. This paper presents a novel non-linear transient dynamics

Jing-en Luan; Tong Yan Tee

2004-01-01

161

A review of experiments and results from the transient reactor test (TREAT) facility  

Microsoft Academic Search

The TREAT Facility was designed and built in the late 1950s at Argonne National Laboratory to provide a transient reactor for safety experiments on samples of reactor fuels. It first operated in 1959. Throughout its history, experiments conducted in TREAT have been important in establishing the behavior of a wide variety of reactor fuel elements under conditions predicted to occur

Deitrich

1998-01-01

162

Geostatistical inverse modeling of transient pumping tests using temporal moments of drawdown  

E-print Network

of storativity affect the estimate of the transmissivity field, and we analyze the effect of truncating, such as the hydraulic conductivity and the specific storage coef- ficient. Among the most common techniques for hydro is determined by the distribution of transmissivity alone, the transient behavior is also influenced

Cirpka, Olaf Arie

163

Constitutive modeling of superalloy single crystals with verification testing  

NASA Technical Reports Server (NTRS)

The goal is the development of constitutive equations to describe the elevated temperature stress-strain behavior of single crystal turbine blade alloys. The program includes both the development of a suitable model and verification of the model through elevated temperature-torsion testing. A constitutive model is derived from postulated constitutive behavior on individual crystallographic slip systems. The behavior of the entire single crystal is then arrived at by summing up the slip on all the operative crystallographic slip systems. This type of formulation has a number of important advantages, including the prediction orientation dependence and the ability to directly represent the constitutive behavior in terms which metallurgists use in describing the micromechanisms. Here, the model is briefly described, followed by the experimental set-up and some experimental findings to date.

Jordan, Eric; Walker, Kevin P.

1985-01-01

164

Global nuclear energy partnership fuels transient testing at the Sandia National Laboratories nuclear facilities : planning and facility infrastructure options.  

SciTech Connect

The Global Nuclear Energy Partnership fuels development program is currently developing metallic, oxide, and nitride fuel forms as candidate fuels for an Advanced Burner Reactor. The Advance Burner Reactor is being designed to fission actinides efficiently, thereby reducing the long-term storage requirements for spent fuel repositories. Small fuel samples are being fabricated and evaluated with different transuranic loadings and with extensive burnup using the Advanced Test Reactor. During the next several years, numerous fuel samples will be fabricated, evaluated, and tested, with the eventual goal of developing a transmuter fuel database that supports the down selection to the most suitable fuel type. To provide a comparative database of safety margins for the range of potential transmuter fuels, this report describes a plan to conduct a set of early transient tests in the Annular Core Research Reactor at Sandia National Laboratories. The Annular Core Research Reactor is uniquely qualified to perform these types of tests because of its wide range of operating capabilities and large dry central cavity which extents through the center of the core. The goal of the fuels testing program is to demonstrate that the design and fabrication processes are of sufficient quality that the fuel will not fail at its design limit--up to a specified burnup, power density, and operating temperature. Transient testing is required to determine the fuel pin failure thresholds and to demonstrate that adequate fuel failure margins exist during the postulated design basis accidents.

Kelly, John E.; Wright, Steven Alan; Tikare, Veena; MacLean, Heather J. (Idaho National Laboratory, Idaho Falls, ID); Parma, Edward J., Jr.; Peters, Curtis D.; Vernon, Milton E.; Pickard, Paul S.

2007-10-01

165

Transient thermal analysis of PWR’s by a single-pass procedure using a simplified nodal layout  

E-print Network

PWR accident conditions and analysis methods have been reviewed. Limitations of the simplified method with respect to analysis of these accident conditions are drawn and two transients ( loss of coolant flow, seized rotor) ...

Liu, Jack S. H.

1979-01-01

166

Transient improvement of poststroke apathy with zolpidem: a single-case, placebo-controlled double-blind study.  

PubMed

We report the case of a 44-year-old patient with severe and disabling apathy nearly 2 years after a right hemisphere haemorrhagic stroke. The effect of a single dose of zolpidem was tested over a 2-week period, in alternation with either no treatment or a placebo in a double-blind randomised trial. Zolpidem was associated with a dramatic improvement in apathy, as assessed with the Apathy Inventory and the Behavioral Dysexecutive Syndrome Inventory. No adverse effect occurred during the trial. PMID:23396925

Autret, Katell; Arnould, Annabelle; Mathieu, Sarah; Azouvi, Philippe

2013-01-01

167

Single-pass rub testing of abradable seal materials  

NASA Technical Reports Server (NTRS)

A pendulum-type test device has been built for use in studying rubs between a turbine or compressor blade tip or labyrinth seal knife edge and specimens of abradable gas path seal materials. The device allows measurement of the rub energy dissipated in a single wear event, along with friction and normal forces and wear. Subsequent rubs over the same surface can also be monitored, with microscopic observation of the rub surface being possible after any of the passes. The device was used in tests of several potential abradable materials, ranging from porous to fully dense. It was shown that the rub energy dissipated in initial and subsequent passes is a fundamental parameter in the evaluation of material abradability. Rub energy was found to be influenced by such factors as: density and tensile (or yield) strength of the abradable material, prior densification or work hardening of the rub surface, and the sharpness of the leading edge of the blade tip.

Kennedy, F. E.; Hine, N. P.

1981-01-01

168

Component test toward single-flux-quantum processors  

NASA Astrophysics Data System (ADS)

We have developed essential components for most of microarchitectures based on the single-flux-quantum (SFQ) logic. The circuit under test is composed of two registers, an ALU and a control unit, and made up of about 540 cells, 1600 Josephson junctions on 1.5 × 2.4 mm area. We have obtained the correct results by a sequence of several instructions, in which two integers are written into the registers with the LOAD and COPY operations, and then execute the ADD operation. Some of their functions were tested at both low and high frequencies. As a result, we found that the designed components could work at 15 GHz for the designed bias current and up to 18 GHz for higher bias currents.

Tanaka, M.; Kondo, T.; Sekiya, A.; Fujimaki, A.; Hayakawa, H.; Matsuzaki, F.; Yoshikawa, N.; Terai, H.; Yorozu, S.

169

Design, fabrication and testing of single spoke resonators at Fermilab  

SciTech Connect

The Fermilab High Intensity Neutrino Source (HINS) linac R&D program is building a pulsed 30 MeV superconducting H- linac. The linac incorporates superconducting solenoids, high power RF vector modulators and superconducting spoke-type accelerating cavities starting at 10 MeV. This will be the first application and demonstration of any of these technologies in a low-energy, high-intensity proton/H- linac. The HINS effort is relevant to a high intensity, superconducting H- linac that might serve the next generation of neutrino physics and muon storage ring/collider experiments. In this paper we present the RF design, the mechanical design, the fabrication, the chemistry and testing of the first two SSR1 (Single Spoke Resonator type-1) prototype cavities that were built. These cavities operate at 325 MHz with {beta} = 0.21. The design and testing of the input coupler and the tuning mechanism are also discussed.

Ristori, L.; Apollinari, G.; Borissov, E.; Gonin, I.V.; Khabiboulline, T.N.; Mukherjee, A.; Nicol, T.H.; Ozelis, J.; Pischalnikov, Y.; Sergatskov, D.A.; Wagner, R.; /Fermilab

2009-09-01

170

Engineering test results for the Moog Single Line Disconnect  

NASA Technical Reports Server (NTRS)

New and innovative types of disconnects will be required to service, resupply, and maintain future spacecraft subsystems. Efficiently maintaining orbiting scientific instruments, spacecraft support systems, and a manned space station over a long period of time will require the periodic replenishment of consumables and the replacement of components. To accomplish these tasks, the fluid disconnect must be designed to allow the connection and separation of fluid lines and components with minimal hazard to crew and equipment. The capability to simply connect a refueling line or to easily replace a failed component greatly extends the life of a space based fluid system. A test program was initiated to evaluate the Moog Single Line Disconnect. The objective of the test program was to demonstrate the operational characteristics of the disconnect and to verify compliance with current safety regulations. The results of the program are summarized in the referenced document.

Glubke, Scott E.

1990-01-01

171

Investigation of Transients in Single-Fiber Bidirectional Closed-Loop WDM Ring Network Using High-Power Gain Clamped EDWA  

Microsoft Academic Search

We investigate a transparent WDM ring network design immune to accumulated power transients where simultaneous bidirectional operation is achieved on a single fiber. This allows cost effectiveness, flexible traffic re-routing, and network operation. We demonstrate that add\\/drop of 15 out of 16 channels generate negligible (< 0.15 dB) power excursion on the surviving channel. These results have been obtained by

K. Ennser; G. Della Valle; S. Taccheo

2009-01-01

172

Transient performance of a single-phase self-regulated self-excited induction generator using a three-phase machine  

Microsoft Academic Search

This paper presents the transient behavior of a three-phase star connected self-excited induction generator (SEIG) using three capacitors connected in series and parallel with a single-phase load. The voltage regulation of this generator is very small due to the effect of three capacitors. The dynamic model of the above generator has been developed based on stationary reference frame d–q-axes theory

S. N. Mahato; M. P. Sharma; S. P. Singh

2007-01-01

173

Radiation tests of single photon avalanche diode for space applications  

NASA Astrophysics Data System (ADS)

Single photon avalanche diodes (SPADs) have been recently studied as photodetectors for applications in space missions. In this presentation we report the results of radiation hardness test on large area SPAD (actual results refer to SPADs having 500 ?m diameter). Dark counts rate as low as few kHz at -10 °C has been obtained for the 500 ?m devices, before irradiation. We performed bulk damage and total dose radiation tests with protons and gamma-rays in order to evaluate their radiation hardness properties and their suitability for application in a Low Earth Orbit (LEO) space mission. With this aim SPAD devices have been irradiated using up to 20 krad total dose with gamma-rays and 5 krad with protons. The test performed show that large area SPADs are very sensitive to proton doses as low as 2×108 (1 MeV eq) n/cm2 with a significant increase in dark counts rate (DCR) as well as in the manifestation of the "random telegraph signal" effect. Annealing studies at room temperature (RT) and at 80 °C have been carried out, showing a high decrease of DCR after 24-48 h at RT. Lower protons doses in the range 1-10×107 (1 MeV eq) n/cm2 result in a lower increase of DCR suggesting that the large-area SPADs tested in this study are well suitable for application in low-inclination LEO, particularly useful for gamma-ray astrophysics.

Moscatelli, Francesco; Marisaldi, Martino; Maccagnani, Piera; Labanti, Claudio; Fuschino, Fabio; Prest, Michela; Berra, Alessandro; Bolognini, Davide; Ghioni, Massimo; Rech, Ivan; Gulinatti, Angelo; Giudice, Andrea; Simmerle, Georg; Candelori, Andrea; Mattiazzo, Serena; Sun, Xiaoli; Cavanaugh, John F.; Rubini, Danilo

2013-05-01

174

Cultural Resource Investigations for the Resumption of Transient Testing of Nuclear Fuels and Material at the Idaho National Laboratory  

SciTech Connect

The U. S. Department of Energy (DOE) has a need to test nuclear fuels under conditions that subject them to short bursts of intense, high-power radiation called ‘transient testing’ in order to gain important information necessary for licensing new nuclear fuels for use in U.S. nuclear power plants, for developing information to help improve current nuclear power plant performance and sustainability, for improving the affordability of new generation reactors, for developing recyclable nuclear fuels, and for developing fuels that inhibit any repurposing into nuclear weapons. To meet this mission need, DOE is considering alternatives for re-use and modification of existing nuclear reactor facilities to support a renewed transient testing program. One alternative under consideration involves restarting the Transient Reactor Test (TREAT) reactor located at the Materials and Fuels Complex (MFC) on the Idaho National Laboratory (INL) site in southeastern Idaho. This report summarizes cultural resource investigations conducted by the INL Cultural Resource Management Office in 2013 to support environmental review of activities associated with restarting the TREAT reactor at the INL. These investigations were completed in order to identify and assess the significance of cultural resources within areas of potential effect associated with the proposed action and determine if the TREAT alternative would affect significant cultural resources or historic properties that are eligible for nomination to the National Register of Historic Places. No archaeological resources were identified in the direct area of potential effects for the project, but four of the buildings proposed for modifications are evaluated as historic properties, potentially eligible for nomination to the National Register of Historic Places. This includes the TREAT reactor (building #), control building (building #), guardhouse (building #), and warehouse (building #). The proposed re-use of these historic properties is consistent with original missions related to nuclear reactor testing and is expected to result in no adverse effects to their historic significance. Cultural resource investigations also involved communication with representatives from the Shoshone-Bannock Tribes to characterize cultural resources of potential tribal concern. This report provides a summary of the cultural resources inventoried and assessed within the defined areas of potential effect for the resumption of transient testing at the INL. Based on these analyses, proposed activities would have no adverse effects on historic properties within the APEs that have been defined. Other archaeological resources and cultural resources of potential concern to the Shoshone-Bannock Tribes and others that are located near the APEs are also discussed with regard to potential indirect impacts. The report concludes with general recommendations for measures to reduce impacts to all identified resources.

Brenda R. Pace; Julie B. Williams

2013-11-01

175

Classification of Transient Phenomena in Distribution System using wavelet Transform  

NASA Astrophysics Data System (ADS)

An efficient procedure for classification of transient phenomena in distribution systems is proposed in this paper. The proposed method has been applied to classify some transient phenomena such as inrush current, load switching, capacitor switching and single phase to ground fault. The new scheme is based on wavelet transform algorithm. All of the events for feature extraction and test are simulated using Electro Magnetic Transient Program (EMTP). Results show high accuracy of proposed method.

Sedighi, Alireza

2014-05-01

176

IGR J17354-3255 as bench test for investigation of ?-ray emission from Supergiant Fast X-ray Transients  

NASA Astrophysics Data System (ADS)

Among the different types of sources shining in the high energy sky, gamma-ray binaries are rapidly becoming the subject of major interest. In fact, in the last few years a number of High Mass X-ray Binaries (HMXBs) have been firmly detected from MeV to TeV energies, providing secure evidences that particles can be efficiently accelerated up to very high energies in such galactic systems. Similarly to this general and emerging class of gamma-ray binaries, in principle Supergiant Fast X-ray Transients (SFXTs) have all the "ingredients" to be transient high energy emitters. In this context, the SFXT IGR J17354-3255 is a good bench test and we present intriguing hints likely suggesting that it is a transient gamma-ray source flaring on short timescales. If fully confirmed by further studies, the implications stemming are huge, both theoretically and observationally, and would add a further extreme characteristic to the already extreme class of SFXTs.

Sguera, V.

2013-06-01

177

Single Component Sorption-Desorption Test Experimental Design Approach Discussions  

SciTech Connect

A task was identified within the fission-product-transport work package to develop a path forward for doing testing to determine behavior of volatile fission products behavior and to engage members of the NGNP community to advise and dissent on the approach. The following document is a summary of the discussions and the specific approaches suggested for components of the testing. Included in the summary isare the minutes of the conference call that was held with INL and external interested parties to elicit comments on the approaches brought forward by the INL participants. The conclusion was that an initial non-radioactive, single component test will be useful to establish the limits of currently available chemical detection methods, and to evaluated source-dispersion uniformity. In parallel, development of a real-time low-concentration monitoring method is believed to be useful in detecting rapid dispersion as well as desorption phenomena. Ultimately, the test cycle is expected to progress to the use of radio-traced species, simply because this method will allow the lowest possible detection limits. The consensus of the conference call was that there is no need for an in-core test because the duct and heat exchanger surfaces that will be the sorption target will be outside the main neutron flux and will not be affected by irradiation. Participants in the discussion and contributors to the INL approach were Jeffrey Berg, Pattrick Calderoni, Gary Groenewold, Paul Humrickhouse, Brad Merrill, and Phil Winston. Participants from outside the INL included David Hanson of General Atomics, Todd Allen, Tyler Gerczak, and Izabela Szlufarska of the University of Wisconsin, Gary Was, of the University of Michigan, Sudarshan Loyalka and Tushar Ghosh of the University of Missouri, and Robert Morris of Oak Ridge National Laboratory.

Phil WInston

2011-09-01

178

49 CFR 232.309 - Equipment and devices used to perform single car air brake tests.  

Code of Federal Regulations, 2010 CFR

...Equipment and devices used to perform single car air brake tests. 232.309 Section...Equipment and devices used to perform single car air brake tests. (a) Equipment and devices used to perform single car air brake tests shall be tested for...

2010-10-01

179

49 CFR 232.309 - Equipment and devices used to perform single car air brake tests.  

Code of Federal Regulations, 2011 CFR

...Equipment and devices used to perform single car air brake tests. 232.309 Section...Equipment and devices used to perform single car air brake tests. (a) Equipment and devices used to perform single car air brake tests shall be tested for...

2011-10-01

180

49 CFR 232.309 - Equipment and devices used to perform single car air brake tests.  

Code of Federal Regulations, 2012 CFR

...Equipment and devices used to perform single car air brake tests. 232.309 Section...Equipment and devices used to perform single car air brake tests. (a) Equipment and devices used to perform single car air brake tests shall be tested for...

2012-10-01

181

49 CFR 232.309 - Equipment and devices used to perform single car air brake tests.  

Code of Federal Regulations, 2013 CFR

...Equipment and devices used to perform single car air brake tests. 232.309 Section...Equipment and devices used to perform single car air brake tests. (a) Equipment and devices used to perform single car air brake tests shall be tested for...

2013-10-01

182

78 FR 44189 - Petition for Modification of Single Car Air Brake Test Procedures  

Federal Register 2010, 2011, 2012, 2013

...FRA-2013-0064] Petition for Modification of Single Car Air Brake Test Procedures In accordance...per 49 CFR 232.307 to modify the single car air brake test procedures located in AAR...System Tests for Freight Equipment-- Single Car Test, and required pursuant to 49 CFR...

2013-07-23

183

ATHENA (Advanced Thermal-Hydraulic Energy Network Analyzer) transient analysis of a fusion engineering test reactor  

SciTech Connect

Two potential undercooling transients are of concern in the design of TIBER-II (Tokamak Ignition/Burn Experimental Reactor), namely loss of coolant and loss of flow accidents. The major area of concern for TIBER-II is the inboard shield, where, due to tungsten material, the decay heat is extremely high. The purpose of this study was to analyze these transients using the thermal-hydraulic code ATHENA (Advanced Thermal-Hydraulic Energy Network Analyzer). The most comprehensive portion of this project involved creating a simple, yet complete, ATHENA model representative of TIBER-II. The completed model represents the case when the plasma is off and contains the inboard shield, the outboard shield, the divertor shields, and the primary loop. The primary loop contains the piping, pump, pressurizer, and heat exchanger. The heat exchanger is at the same elevation as the reactor, the least favorable to establishing natural circulation. The only transient analyzed so far, however, is a loss of flow accident. Results from the loss of flow analysis show that there is sufficient natural circulation in the inboard, outboard, and lower divertor shield to remove the decay heat, assuming that the secondary side flow is at full capacity. Although the upper divertor shield does not have sufficient natural circulation, cooling is provided due to vaporization and re-flood oscillations. However, one must recognize that there may be some local hot sport where the flow geometry inhibits cooling in a LOFA; the ATHENA model would not detect any localized problem. 9 refs., 18 figs., 4 tabs.

Wareing, T.A.

1988-02-01

184

Transient Plume Model Testing Using LADEE Spacecraft Attitude Control System Operations  

NASA Technical Reports Server (NTRS)

We have learned it is conceivable that the Neutral Mass Spectrometer on board the Lunarr Atmosphere Dust Environment Explorer (LADEE) could measure gases from surface-reflected Attitude Control System (ACS) thruster plume. At minimum altitude, the measurement would be maximized, and gravitational influence minimized ("short" time-of-flight (TOF) situation) Could use to verify aspects of thruster plume modeling Model the transient disturbance to NMS measurements due to ACS gases reflected from lunar surface Observe evolution of various model characteristics as measured by NMS Species magnitudes, TOF measurements, angular distribution, species separation effects

Woronowicz, Michael

2011-01-01

185

Results of MPBX studies at the single heater test  

SciTech Connect

We have developed an extensometer for measurement of distance and displacements in a geologic repository for high-level nuclear waste. This is an optical extensometer that measures distance using a modulated laser beam. In this design, reflecting targets are placed at desired measurement locations, and distance between each target and an optical head are measured repeatedly using the modulated laser beam. Moreover, all electronic and moving parts are located outside of the hostile or difficult environment as the optical head is connected to the laser, switching and signal analysis hardware using optical fibers. A reference beam is utilized to provide direct correction of system behavior. `Be system also - utilizes movable reflective anchors that can be repositioned if desired. We have installed the system in the Single Heater Test being conducted in Alcove 5 of the Exploratory Studies Facility at Yucca Mountain, and report preliminary results.

Blair, S. C.,LLNL

1997-10-01

186

Testing the single degenerate channel for supernova Ia  

NASA Astrophysics Data System (ADS)

The progenitors of supernova Ia are close binaries containing white dwarfs. Of crucial importance to the evolution of these systems is how much material the white dwarf can stably accrete and hence grow in mass. This occurs during a short-lived intense phase of mass transfer known as the super soft source (SSS) phase. The short duration of this phase and large extinction to soft X-rays means that only a handful are known in our Galaxy. Far more can be learned from the underlying SSS progenitor population of close white dwarf plus FGK type binaries. Unfortunately, these systems are hard to find since the main-sequence stars completely outshine the white dwarfs at optical wavelengths. Because of this, there are currently no known close white dwarf binaries with F, G or early K type companions, making it impossible to determine the contribution of the single degenerate channel towards supernova Ia. Using the GALEX and RAVE surveys we have now identified the first large sample of FGK stars with UV excesses, a fraction of which are these illusive, close systems. Following an intense ground based spectroscopic investigation of these systems, we have identified 5 definite close binaries, with periods of less than a few days. Here we apply for COS spectroscopic observations to measure the mass and temperature of the white dwarfs in order to determine the future evolution of these systems. This will provide a crucial test for the single degenerate channel towards supernova Ia.

Parsons, Steven

2014-10-01

187

40 CFR 1048.510 - What transient duty cycles apply for laboratory testing?  

Code of Federal Regulations, 2013 CFR

...duty cycles apply for laboratory testing? 1048.510 Section...Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...duty cycles apply for laboratory testing? (a) Starting...measure emissions by testing the engine on...

2013-07-01

188

40 CFR 1048.510 - What transient duty cycles apply for laboratory testing?  

Code of Federal Regulations, 2012 CFR

...duty cycles apply for laboratory testing? 1048.510 Section...Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...duty cycles apply for laboratory testing? (a) Starting...measure emissions by testing the engine on...

2012-07-01

189

40 CFR 1048.510 - What transient duty cycles apply for laboratory testing?  

Code of Federal Regulations, 2011 CFR

...duty cycles apply for laboratory testing? 1048.510 Section...Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...duty cycles apply for laboratory testing? (a) Starting...measure emissions by testing the engine on...

2011-07-01

190

49 CFR 232.307 - Modification of the single car air brake test procedures.  

Code of Federal Regulations, 2011 CFR

...307 Modification of the single car air brake test procedures. (a) Request...may seek modification of the single car air brake test procedures prescribed...decision. FRA may attach special conditions to the approval of any request...

2011-10-01

191

49 CFR 232.307 - Modification of the single car air brake test procedures.  

Code of Federal Regulations, 2013 CFR

...307 Modification of the single car air brake test procedures. (a) Request...may seek modification of the single car air brake test procedures prescribed...decision. FRA may attach special conditions to the approval of any request...

2013-10-01

192

49 CFR 232.307 - Modification of the single car air brake test procedures.  

Code of Federal Regulations, 2012 CFR

...307 Modification of the single car air brake test procedures. (a) Request...may seek modification of the single car air brake test procedures prescribed...decision. FRA may attach special conditions to the approval of any request...

2012-10-01

193

49 CFR 232.307 - Modification of the single car air brake test procedures.  

Code of Federal Regulations, 2010 CFR

...307 Modification of the single car air brake test procedures. (a) Request...may seek modification of the single car air brake test procedures prescribed...decision. FRA may attach special conditions to the approval of any request...

2010-10-01

194

Implementation and testing of the first prompt search for gravitational wave transients with electromagnetic counterparts  

E-print Network

Aims. A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in association with several partners. In this paper, we describe and evaluate the methods used to promptly identify and localize GW event candidates and to request images of targeted sky locations. Methods. During two observing periods (Dec 17 2009 to Jan 8 2010 and Sep 2 to Oct 20 2010), a low-latency analysis pipeline was used to identify GW event candidates and to reconstruct maps of possible sky locations. A catalog of nearby galaxies and Milky Way globular clusters was used to select the most promising sky positions to be imaged, and this directional information was delivered to EM observatories with time lags of about thirty minutes. A Monte Carlo simulation has been used to evaluate the low-latency GW pipeline's ability to reconstruct source positions correctly. Results. For signals near the detection threshold, our low-latency algorithms often localized simulated GW burst signals to tens of square degrees, while neutron star/neutron star inspirals and neutron star/black hole inspirals were localized to a few hundred square degrees. Localization precision improves for moderately stronger signals. The correct sky location of signals well above threshold and originating from nearby galaxies may be observed with ~50% or better probability with a few pointings of wide-field telescopes.

The LIGO Scientific Collaboration; Virgo Collaboration; J. Abadie; B. P. Abbott; R. Abbott; T. D. Abbott; M. Abernathy; T. Accadia; F. Acernese; C. Adams; R. Adhikari; C. Affeldt; P. Ajith; B. Allen; G. S. Allen; E. Amador Ceron; D. Amariutei; R. S. Amin; S. B. Anderson; W. G. Anderson; K. Arai; M. A. Arain; M. C. Araya; S. M. Aston; P. Astone; D. Atkinson; P. Aufmuth; C. Aulbert; B. E. Aylott; S. Babak; P. Baker; G. Ballardin; S. Ballmer; D. Barker; F. Barone; B. Barr; P. Barriga; L. Barsotti; M. Barsuglia; M. A. Barton; I. Bartos; R. Bassiri; M. Bastarrika; A. Basti; J. Batch; J. Bauchrowitz; Th. S. Bauer; M. Bebronne; B. Behnke; M. G. Beker; A. S. Bell; A. Belletoile; I. Belopolski; M. Benacquista; J. M. Berliner; A. Bertolini; J. Betzwieser; N. Beveridge; P. T. Beyersdorf; I. A. Bilenko; G. Billingsley; J. Birch; R. Biswas; M. Bitossi; M. A. Bizouard; E. Black; J. K. Blackburn; L. Blackburn; D. Blair; B. Bland; M. Blom; O. Bock; T. P. Bodiya; C. Bogan; R. Bondarescu; F. Bondu; L. Bonelli; R. Bonnand; R. Bork; M. Born; V. Boschi; S. Bose; L. Bosi; B. Bouhou; S. Braccini; C. Bradaschia; P. R. Brady; V. B. Braginsky; M. Branchesi; J. E. Brau; J. Breyer; T. Briant; D. O. Bridges; A. Brillet; M. Brinkmann; V. Brisson; M. Britzger; A. F. Brooks; D. A. Brown; A. Brummit; T. Bulik; H. J. Bulten; A. Buonanno; J. Burguet--Castell; O. Burmeister; D. Buskulic; C. Buy; R. L. Byer; L. Cadonati; G. Cagnoli; J. Cain; E. Calloni; J. B. Camp; P. Campsie; J. Cannizzo; K. Cannon; B. Canuel; J. Cao; C. D. Capano; F. Carbognani; S. Caride; S. Caudill; M. Cavaglià; F. Cavalier; R. Cavalieri; G. Cella; C. Cepeda; E. Cesarini; O. Chaibi; T. Chalermsongsak; E. Chalkley; P. Charlton; E. Chassande-Mottin; S. Chelkowski; Y. Chen; A. Chincarini; A. Chiummo; H. Cho; N. Christensen; S. S. Y. Chua; C. T. Y. Chung; S. Chung; G. Ciani; F. Clara; D. E. Clark; J. Clark; J. H. Clayton; F. Cleva; E. Coccia; P. -F. Cohadon; C. N. Colacino; J. Colas; A. Colla; M. Colombini; A. Conte; R. Conte; D. Cook; T. R. Corbitt; M. Cordier; N. Cornish; A. Corsi; C. A. Costa; M. Coughlin; J. -P. Coulon; P. Couvares; D. M. Coward; D. C. Coyne; J. D. E. Creighton; T. D. Creighton; A. M. Cruise; A. Cumming; L. Cunningham; E. Cuoco; R. M. Cutler; K. Dahl; S. L. Danilishin; R. Dannenberg; S. D'Antonio; K. Danzmann; V. Dattilo; B. Daudert; H. Daveloza; M. Davier; G. Davies; E. J. Daw; R. Day; T. Dayanga; R. De Rosa; D. DeBra; G. Debreczeni; J. Degallaix; W. Del Pozzo; M. del Prete; T. Dent; V. Dergachev; R. DeRosa; R. DeSalvo; V. Dhillon; S. Dhurandhar; L. Di Fiore; A. Di Lieto; I. Di Palma; M. Di Paolo Emilio; A. Di Virgilio; M. Díaz; A. Dietz; F. Donovan; K. L. Dooley; S. Dorsher; M. Drago; R. W. P. Drever; J. C. Driggers; Z. Du; J. -C. Dumas; S. Dwyer; T. Eberle; M. Edgar; M. Edwards; A. Effler; P. Ehrens; G. Endr?czi; R. Engel; T. Etzel; K. Evans; M. Evans; T. Evans; M. Factourovich; V. Fafone; S. Fairhurst; Y. Fan; B. F. Farr; W. Farr; D. Fazi; H. Fehrmann; D. Feldbaum; I. Ferrante; F. Fidecaro; L. S. Finn; I. Fiori; R. P. Fisher; R. Flaminio; M. Flanigan; S. Foley; E. Forsi; L. A. Forte; N. Fotopoulos; J. -D. Fournier; J. Franc; S. Frasca; F. Frasconi; M. Frede; M. Frei; Z. Frei; A. Freise; R. Frey; T. T. Fricke; J. K. Fridriksson; D. Friedrich; P. Fritschel; V. V. Frolov; P. J. Fulda; M. Fyffe; M. Galimberti; L. Gammaitoni; M. R. Ganija; J. Garcia; J. A. Garofoli; F. Garufi; M. E. Gáspár; G. Gemme; R. Geng; E. Genin; A. Gennai; L. Á. Gergely; S. Ghosh; J. A. Giaime; S. Giampanis; K. D. Giardina; A. Giazotto; C. Gill; E. Goetz; L. M. Goggin; G. González; M. L. Gorodetsky; S. Goßler; R. Gouaty; C. Graef; M. Granata; A. Grant; S. Gras; C. Gray; N. Gray; R. J. S. Greenhalgh; A. M. Gretarsson; C. Greverie; R. Grosso; H. Grote; S. Grunewald; G. M. Guidi; C. Guido; R. Gupta; E. K. Gustafson; R. Gustafson; T. Ha; B. Hage; J. M. Hallam; D. Hammer; G. Hammond; J. Hanks; C. Hanna; J. Hanson; J. Harms; G. M. Harry; I. W. Harry; E. D. Harstad; M. T. Hartman; K. Haughian; K. Hayama; J. -F. Hayau; T. Hayler; J. Heefner; A. Heidmann; M. C. Heintze; H. Heitmann; P. Hello; M. A. Hendry; I. S. Heng; A. W. Heptonstall; V. Herrera; M. Hewitson; S. Hild; D. Hoak; K. A. Hodge; K. Holt; J. Homan; T. Hong; S. Hooper; D. J. Hosken; J. Hough; E. J. Howell; B. Hughey; S. Husa; S. H. Huttner; T. Huynh-Dinh; D. R. Ingram; R. Inta; T. Isogai; A. Ivanov; K. Izumi; M. Jacobson; H. Jang; P. Jaranowski; W. W. Johnson; D. I. Jones; G. Jones; R. Jones; L. Ju; P. Kalmus; V. Kalogera; I. Kamaretsos; S. Kandhasamy; G. Kang; J. B. Kanner; E. Katsavounidis; W. Katzman; H. Kaufer; K. Kawabe; S. Kawamura; F. Kawazoe; W. Kells; D. G. Keppel; Z. Keresztes; A. Khalaidovski; F. Y. Khalili; E. A. Khazanov; B. Kim; C. Kim; D. Kim; H. Kim; K. Kim; N. Kim; Y. -M. Kim; P. J. King; M. Kinsey; D. L. Kinzel; J. S. Kissel; S. Klimenko; K. Kokeyama; V. Kondrashov; R. Kopparapu

2011-09-15

195

Implementation and testing of the first prompt search for gravitational wave transients with electromagnetic counterparts  

NASA Astrophysics Data System (ADS)

Aims: A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in association with several partners. In this paper, we describe and evaluate the methods used to promptly identify and localize GW event candidates and to request images of targeted sky locations. Methods: During two observing periods (Dec. 17, 2009 to Jan. 8, 2010 and Sep. 2 to Oct. 20, 2010), a low-latency analysis pipeline was used to identify GW event candidates and to reconstruct maps of possible sky locations. A catalog of nearby galaxies and Milky Way globular clusters was used to select the most promising sky positions to be imaged, and this directional information was delivered to EM observatories with time lags of about thirty minutes. A Monte Carlo simulation has been used to evaluate the low-latency GW pipeline's ability to reconstruct source positions correctly. Results: For signals near the detection threshold, our low-latency algorithms often localized simulated GW burst signals to tens of square degrees, while neutron star/neutron star inspirals and neutron star/black hole inspirals were localized to a few hundred square degrees. Localization precision improves for moderately stronger signals. The correct sky location of signals well above threshold and originating from nearby galaxies may be observed with ~50% or better probability with a few pointings of wide-field telescopes.

LIGO Scientific Collaboration; Virgo Collaboration; Abadie, J.; Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M.; Accadia, T.; Acernese, F.; Adams, C.; Adhikari, R.; Affeldt, C.; Ajith, P.; Allen, B.; Allen, G. S.; Amador Ceron, E.; Amariutei, D.; Amin, R. S.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Arain, M. A.; Araya, M. C.; Aston, S. M.; Astone, P.; Atkinson, D.; Aufmuth, P.; Aulbert, C.; Aylott, B. E.; Babak, S.; Baker, P.; Ballardin, G.; Ballmer, S.; Barker, D.; Barone, F.; Barr, B.; Barriga, P.; Barsotti, L.; Barsuglia, M.; Barton, M. A.; Bartos, I.; Bassiri, R.; Bastarrika, M.; Basti, A.; Batch, J.; Bauchrowitz, J.; Bauer, Th. S.; Bebronne, M.; Behnke, B.; Beker, M. G.; Bell, A. S.; Belletoile, A.; Belopolski, I.; Benacquista, M.; Berliner, J. M.; Bertolini, A.; Betzwieser, J.; Beveridge, N.; Beyersdorf, P. T.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Biswas, R.; Bitossi, M.; Bizouard, M. A.; Black, E.; Blackburn, J. K.; Blackburn, L.; Blair, D.; Bland, B.; Blom, M.; Bock, O.; Bodiya, T. P.; Bogan, C.; Bondarescu, R.; Bondu, F.; Bonelli, L.; Bonnand, R.; Bork, R.; Born, M.; Boschi, V.; Bose, S.; Bosi, L.; Bouhou, B.; Braccini, S.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Breyer, J.; Briant, T.; Bridges, D. O.; Brillet, A.; Brinkmann, M.; Brisson, V.; Britzger, M.; Brooks, A. F.; Brown, D. A.; Brummit, A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Burguet-Castell, J.; Burmeister, O.; Buskulic, D.; Buy, C.; Byer, R. L.; Cadonati, L.; Cagnoli, G.; Calloni, E.; Camp, J. B.; Campsie, P.; Cannizzo, J.; Cannon, K.; Canuel, B.; Cao, J.; Capano, C. D.; Carbognani, F.; Caride, S.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C.; Cesarin, E.; Chaibi, O.; Chalermsongsak, T.; Chalkley, E.; Charlton, P.; Chassande-Mottin, E.; Chelkowski, S.; Chen, Y.; Chincarini, A.; Chiummo, A.; Cho, H.; Christensen, N.; Chua, S. S. Y.; Chung, C. T. Y.; Chung, S.; Ciani, G.; Clara, F.; Clark, D. E.; Clark, J.; Clayton, J. H.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colacino, C. N.; Colas, J.; Colla, A.; Colombini, M.; Conte, A.; Conte, R.; Cook, D.; Corbitt, T. R.; Cordier, M.; Cornish, N.; Corsi, A.; Costa, C. A.; Coughlin, M.; Coulon, J.-P.; Couvares, P.; Coward, D. M.; Coyne, D. C.; Creighton, J. D. E.; Creighton, T. D.; Cruise, A. M.; Cumming, A.; Cunningham, L.; Cuoco, E.; Cutler, R. M.; Dahl, K.; Danilishin, S. L.; Dannenberg, R.; D'Antonio, S.; Danzmann, K.; Dattilo, V.; Daudert, B.; Daveloza, H.; Davier, M.; Davies, G.; Daw, E. J.; Day, R.; Dayanga, T.; DeRosa, R.; Debra, D.; Debreczeni, G.; Degallaix, J.; Del Pozzo, W.; Del Prete, M.; Dent, T.; Dergachev, V.; Derosa, R.; Desalvo, R.; Dhillon, V.; Dhurandhar, S.; Di Fiore, L.; Di Lieto, A.; Di Palma, I.; De Paolo Emilio, M.; Di Virgilio, A.; Díaz, M.; Dietz, A.; Diguglielmo, J.; Donovan, F.; Dooley, K. L.; Dorsher, S.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Dumas, J.-C.; Dwyer, S.; Eberle, T.; Edgar, M.; Edwards, M.; Effler, A.; Ehrens, P.; Endröczi, G.; Engel, R.; Etzel, T.; Evans, K.; Evans, M.; Evans, T.; Factourovich, M.; Fafone, V.; Fairhurst, S.; Fan, Y.; Farr, B. F.; Farr, W.; Fazi, D.; Fehrmann, H.; Feldbaum, D.; Ferrante, I.; Fidecaro, F.; Finn, L. S.; Fiori, I.; Fisher, R. P.; Flaminio, R.; Flanigan, M.; Foley, S.; Forsi, E.; Forte, L. A.; Fotopoulos, N.; Fournier, J.-D.; Franc, J.; Frasca, S.; Frasconi, F.; Frede, M.; Frei, M.; Frei, Z.; Freise, A.; Frey, R.; Fricke, T. T.; Fridriksson, J. K.; Friedrich, D.; Fritschel, P.; Frolov, V. V.; Fulda, P. J.; Fyffe, M.; Galimberti, M.; Gammaitoni, L.; Ganija, M. R.; Garcia, J.; Garofoli, J. A.; Garufi, F.; Gáspár, M. E.; Gemme, G.; Geng, R.; Genin, E.; Gennai, A.; Gergely, L. Á.; Ghosh, S.; Giaime, J. A.; Giampanis, S.; Giardina, K. D.; Giazotto, A.; Gill, C.; Goetz, E.; Goggin, L. M.; González, G.; Gorodetsky, M. L.; Goßler, S.; Gouaty, R.; Graef, C.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Gray, N.; Greenhalgh, R. J. S.; Gretarsson, A. M.; Greverie, C.; Grosso, R.; Grote, H.; Grunewald, S.; Guidi, G. M.; Guido, C.; Gupta, R.; Gustafson, E. K.; Gustafson, R.; Ha, T.; Hage, B.; Hallam, J. M.; Hammer, D.; Hammond, G.; Hanks, J.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G. M.; Harry, I. W.; Harstad, E. D.; Hartman, M. T.; Haughian, K.; Hayama, K.; Hayau, J.-F.; Hayler, T.; Heefner, J.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hendry, M. A.; Heng, I. S.; Heptonstall, A. W.; Herrera, V.; Hewitson, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Holt, K.; Homan, J.; Hong, T.; Hooper, S.; Hosken, D. J.; Hough, J.; Howell, E. J.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Ingram, D. R.; Inta, R.; Isogai, T.; Ivanov, A.; Izumi, K.; Jacobson, M.; Jang, H.; Jaranowski, P.; Johnson, W. W.; Jones, D. I.; Jones, G.; Jones, R.

2012-04-01

196

Implementation and Testing of the First Prompt for Electromagnetic Counterparts to Gravitational Wave Transients  

NASA Technical Reports Server (NTRS)

A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in association with several partners. In this paper, we describe and evaluate the methods used to promptly identify and localize GW event candidates and to request images of targeted sky locations. Methods. During two observing periods (Dec 17 2009 to Jan 8 2010 and Sep 2 to Oct 20 2010), a low-latency analysis pipeline was used to identify GW-event candidates and to reconstruct-maps of possible sky locations. A catalog of nearby galaxies and Milky Way globular clusters was used to select the most promising sky positions to be imaged, and this directional information was delivered to EM observatories with time lags of about thirty minutes. A Monte Carlo simulation has been used to evaluate the low-latency GW pipeline s ability to reconstruct source positions correctly. Results. For signals near the detection threshold, our low-latency algorithms often localized simulated GW burst signals to tens of square degrees, while neutron star/neutron star inspirals and neutron star/black hole inspirals were localized to a few hundred square degrees. Localization precision improves for moderately stronger signals. The correct sky location of signals well above threshold and originating from nearby galaxies may be observed with 50% or better probability with a few pointings of wide-field telescopes.

Abadie, J.; Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M.; Accadia, T.; Acernese, F.; Adams, C.; Adhikari, R.; Affeldt, C.; Ajith, P.; Allen, B.; Allen, G. S.; Amador Ceron, E.; Amariutei, D.; Amin, R. S.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Arain, M. A.; Araya, M. C.; Blackburn, L.; Camp, J. B.; Cannizzo, J.; Gehrels, N.

2011-01-01

197

Single sub-fs soft-X-ray pulses: generation and measurement with the atomic transient recorder  

Microsoft Academic Search

The change from a zero transition to the maximum amplitude of the electric field of visible light lasts shorter than one femtosecond (1 fs = 10-15 s). By precisely controlling the hyperfast electric field oscillations in a short laser pulse we developed a measuring apparatus--the atomic transient recorder--like an ultrafast stopwatch. This apparatus is capable of measuring the duration of

R. Kienberger; M. Uiberacker; E. Goulielmakis; A. Baltuska; M. Drescher; F. Krausz

2005-01-01

198

Radiation Tests for a Single-GEM Loaded Gaseous Detector  

E-print Network

We report on the systematic study of a single-gas-electron-multiplication (GEM) loaded gaseous detector developed for precision measurements of high-energy particle beams and dose-verification measurements. In the present study, a 256-channel prototype detector with an active area of 16$\\times$16 cm$^{2}$, operated in a continuous current-integration-mode signal-processing method, was manufactured and tested with x rays emitted from a 70-kV x-ray generator and 43-MeV protons provided by the MC50 proton cyclotron at the Korea Institute of Radiological and Medical Science (KIRAMS). The amplified detector response was measured for the x rays with an intensity of about 5$\\times$10$^{6}$ Hz cm$^{-2}$. The linearity of the detector response to the particle flux was examined and validated by using 43-MeV proton beams. The non-uniform development of the amplification for the gas electrons in space was corrected by applying proper calibration to the channel responses of the measured beam-profile data. We concluded fro...

Lee, Kyong Sei; Kim, Sang Yeol; Park, Sung Keun

2014-01-01

199

Neuromodulation at single presynaptic boutons of cerebellar parallel fibers is determined by bouton size and basal action potential-evoked Ca transient amplitude  

PubMed Central

Most presynaptic terminals in the brain contain G-protein coupled receptors that function to reduce action potential-evoked neurotransmitter release. These neuromodulatory receptors, including those for glutamate, GABA, endocannabinoids and adenosine, exert a substantial portion of their effect by reducing evoked presynaptic Ca2+ transients. Many axons form synapses with multiple postsynaptic neurons, but it is unclear if presynaptic attenuation in these synapses is homogeneous, as suggested by population level Ca2+ imaging. We loaded Ca2+-sensitive dyes into cerebellar parallel fiber axons and imaged action potential-evoked Ca2+ transients in individual presynaptic boutons with application of three different neuromodulators and found that adjacent boutons on the same axon showed striking heterogeneity in their strength of attenuation. Moreover, attenuation was predicted by bouton size or basal Ca2+ response: smaller boutons were more sensitive to adenosine A1 agonist but less sensitive to CB1 agonist while boutons with high basal action potential-evoked Ca2+ transient amplitude were more sensitive to mGluR4 agonist. These results suggest that boutons within brief segment of a single parallel fiber axon can have different sensitivities towards neuromodulators and may have different capacities for both short-term and long-term plasticities. PMID:20007482

Zhang, Wei; Linden, David J.

2010-01-01

200

Electro-optic modulator based gate transient suppression for sine-wave gated InGaAs/InP single photon avalanche photodiode  

NASA Astrophysics Data System (ADS)

Capacitive gate transient noise has been problematic for the high-speed single photon avalanche photodiode (SPAD), especially when the operating frequency extends to the gigahertz level. We proposed an electro-optic modulator based gate transient noise suppression method for sine-wave gated InGaAs/InP SPAD. With the modulator, gate transient is up-converted to its higher-order harmonics that can be easily removed by low pass filtering. The proposed method enables online tuning of the operating rate without modification of the hardware setup. At 250 K, detection efficiency of 14.7% was obtained with 4.8×10-6 per gate dark count and 3.6% after-pulse probabilities for 1550-nm optical signal under 1-GHz gating frequency. Experimental results have shown that the performance of the detector can be maintained within a designated frequency range from 0.97 to 1.03 GHz, which is quite suitable for practical high-speed SPAD applications operated around the gigahertz level.

Zhang, Yixin; Zhang, Xuping; Shi, Yuanlei; Ying, Zhoufeng; Wang, Shun

2014-06-01

201

Particle Tracking-Based Strategies For Simulating Transport in a Transient Groundwater Flow Field at Yucca Flat, Nevada Test Site, USA  

Microsoft Academic Search

Developing probabilistic-based calculations of contaminant concentrations over the next 1000 years at Yucca Flat, Nevada Test site, require tremendous computational effort in this highly complex hydrogeologic surface environment. The sources of contamination, underground nuclear tests conducted between 1951 and 1992, not only released radionuclides to the subsurface but also created abrupt, significant changes in rock properties and caused large transients

E. H. Keating; G. Srinivasan; Q. Kang; C. Li; Z. Dash; E. M. Kwicklis

2009-01-01

202

Photo-Induced Current Transient Spectroscopy of Semi-insulating Single Crystal Cs2Hg6S7  

NASA Astrophysics Data System (ADS)

The ternary compound Cs2Hg6S7 has shown considerable promise as a wide gap semiconductor for hard radiation detection at room temperature. We report on the measurement of defect levels in Cs2Hg6S7 using photo-induced current transient spectroscopy. We observe a series of defect levels with mean activation energies of 0.053, 0.052, 0.34, 0.35, and 0.46 eV. The defects are attributed to Cs vacancies and Cs and Hg antisite defects. Defect capture cross-sections are in the range 10-20-10-15 cm2.

Liu, Z.; Peters, J. A.; Li, H.; Kanatzidis, M. G.; Im, J.; Jin, H.; Freeman, A. J.; Wessels, B. W.

2014-09-01

203

Initial test results with single cylinder rhombic drive Stirling engine  

NASA Technical Reports Server (NTRS)

A brief description is given of the GPU 3-2 hardware, the test methods used, and the result of these tests. Comparison is made to unpublished data from similar hydrogen tests performed by the U.S. Army.

Cairelli, J. E.

1978-01-01

204

A REVIEW OF SINGLE SPECIES TOXICITY TESTS: ARE THE TESTS RELIABLE PREDICTORS OF AQUATIC ECOSYSTEM COMMUNITY RESPONSES?  

EPA Science Inventory

This document provides a comprehensive review to evaluate the reliability of indicator species toxicity test results in predicting aquatic ecosystem impacts, also called the ecological relevance of laboratory single species toxicity tests....

205

Single-cell-derived mesenchymal stem cells overexpressing Csx/Nkx2.5 and GATA4 undergo the stochastic cardiomyogenic fate and behave like transient amplifying cells  

SciTech Connect

Bone marrow-derived stromal cells can give rise to cardiomyocytes as well as adipocytes, osteocytes, and chondrocytes in vitro. The existence of mesenchymal stem cells has been proposed, but it remains unclear if a single-cell-derived stem cell stochastically commits toward a cardiac lineage. By single-cell marking, we performed a follow-up study of individual cells during the differentiation of 9-15c mesenchymal stromal cells derived from bone marrow cells. Three types of cells, i.e., cardiac myoblasts, cardiac progenitors and multipotent stem cells were differentiated from a single cell, implying that cardiomyocytes are generated stochastically from a single-cell-derived stem cell. We also demonstrated that overexpression of Csx/Nkx2.5 and GATA4, precardiac mesodermal transcription factors, enhanced cardiomyogenic differentiation of 9-15c cells, and the frequency of cardiomyogenic differentiation was increased by co-culturing with fetal cardiomyocytes. Single-cell-derived mesenchymal stem cells overexpressing Csx/Nkx2.5 and GATA4 behaved like cardiac transient amplifying cells, and still retained their plasticity in vivo.

Yamada, Yoji [BioFrontier Laboratories, Kyowa Hakko Kogyo Co. Ltd., 3-6-6 Asahi-machi, Machida-shi, Tokyo 194-8533 (Japan); Sakurada, Kazuhiro [BioFrontier Laboratories, Kyowa Hakko Kogyo Co. Ltd., 3-6-6 Asahi-machi, Machida-shi, Tokyo 194-8533 (Japan); Takeda, Yukiji [National Research Institute for Child Health and Development, 2-10-1 Okura, Setagaya-ku, Tokyo 157-8535 (Japan); Gojo, Satoshi [National Research Institute for Child Health and Development, 2-10-1 Okura, Setagaya-ku, Tokyo 157-8535 (Japan); Umezawa, Akihiro [National Research Institute for Child Health and Development, 2-10-1 Okura, Setagaya-ku, Tokyo 157-8535 (Japan)]. E-mail: umezawa@1985.jukuin.keio.ac.jp

2007-02-15

206

Summary of air permeability data from single-hole injection tests in unsaturated fractured tuffs at the Apache Leap Research Site: Results of steady-state test interpretation  

SciTech Connect

This document summarizes air permeability estimates obtained from single hole pneumatic injection tests in unsaturated fractured tuffs at the Covered Borehole Site (CBS) within the larger apache Leap Research Site (ALRS). Only permeability estimates obtained from a steady state interpretation of relatively stable pressure and flow rate data are included. Tests were conducted in five boreholes inclined at 45{degree} to the horizontal, and one vertical borehole. Over 180 borehole segments were tested by setting the packers 1 m apart. Additional tests were conducted in segments of lengths 0.5, 2.0, and 3.0 m in one borehole, and 2.0 m in another borehole, bringing the total number of tests to over 270. Tests were conducted by maintaining a constant injection rate until air pressure became relatively stable and remained so for some time. The injection rate was then incremented by a constant value and the procedure repeated. The air injection rate, pressure, temperature, and relative humidity were recorded. For each relatively stable period of injection rate and pressure, air permeability was estimated by treating the rock around each test interval as a uniform, isotropic porous medium within which air flows as a single phase under steady state, in a pressure field exhibiting prolate spheroidal symmetry. For each permeability estimate the authors list the corresponding injection rate, pressure, temperature and relative humidity. They also present selected graphs which show how the latter quantities vary with time; logarithmic plots of pressure versus time which demonstrate the importance of borehole storage effects during the early transient portion of each incremental test period; and semilogarithmic plots of pressure versus recovery time at the end of each test sequence.

Guzman, A.G.; Geddis, A.M.; Henrich, M.J.; Lohrstorfer, C.F.; Neuman, S.P. [Univ. of Arizona, Tucson, AZ (United States). Dept. of Hydrology and Water Resources

1996-03-01

207

Shielding effectiveness of the liquid tight flexible conduit from transient tests  

Microsoft Academic Search

Analysis and tests on a spiral-wrapped, mild steel, flexible conduit ; tube are reported. Experimentally, the transfer impedance was determined by ; attempting to produce a uniformly distributed current in the shield and measuring ; the corresponding electric field on the inside. A capacitor discharging into the ; coaxial line formed by the conduit and an external concentric cylinder provided

Vance

1971-01-01

208

Analysis of the Chlorophyll a Fluorescence Transient of Spirodela polyrhiza by JIP-Test  

Microsoft Academic Search

Chlorophyll a fluorescence has been used as non-invasive probe for stress physiology and environmental investigation. The changes of photosynthetic apparatus in Spirodela polyrrhiza was studied by using chlorophyll a fluorescence technique and JIP-test. During L-serine-induced senescence, photosynthetic performance index (PI), reaction center (RC) decreased gradually and reached zero on the 8th day of cultivation. However, the oxygen evolving complex (OEC)

Hongtao Li; Yu Zhao; Ke Zhu; Jinju Wang; Qingdai Liu; Hongjie An

2010-01-01

209

Using Transient\\/Persistent Errors to Develop Automated Test Oracles for Event-Driven Software  

Microsoft Academic Search

Today's software-intensive systems contain an important class of software, namely event-driven software (EDS). All EDS take events as input, change their state, and (perhaps) output an event sequence. EDS is typically implemented as a collection of event-handlers designed to respond to individual events. The nature of EDS creates new challenges for test automation. In this paper, we focus on those

Atif M. Memon; Qing Xie

2004-01-01

210

The comparative performance of the single intradermal test and the single intradermal comparative tuberculin test in Irish cattle, using tuberculin PPD combinations of differing potencies  

Microsoft Academic Search

In national bovine tuberculosis (BTB) control programmes, testing is generally conducted using a single source of bovine purified protein derivative (PPD) tuberculin. Alternative tuberculin sources should be identified as part of a broad risk management strategy as problems of supply or quality cannot be discounted. This study was conducted to compare the impact of different potencies of a single bovine

M. Good; T. A. Clegg; E. Costello; S. J. More

211

Test report for single event effects of the 80386DX microprocessor  

NASA Technical Reports Server (NTRS)

The Jet Propulsion Laboratory Section 514 Single Event Effects (SEE) Testing and Analysis Group has performed a series of SEE tests of certain strategic registers of Intel's 80386DX CHMOS 4 microprocessor. Following a summary of the test techniques and hardware used to gather the data, we present the SEE heavy ion and proton test results. We also describe the registers tested, along with a system impact analysis should these registers experience a single event upset.

Watson, R. Kevin; Schwartz, Harvey R.; Nichols, Donald K.

1993-01-01

212

Transient Heat-transfer analysis of scaled down SSME Test-Stand Diffuser  

NASA Astrophysics Data System (ADS)

the scaled-down high altitude test-stand simulator is a metalic cylinder where combussed rocket fuels pass through with speed of Mach 4 or 5. The Temperature at diffuser wall can reach as high as 1800 R. These conditions dictate special design for diffuser. Dominant mode of heat transfer is conduction and convection. An analysis using lumped capacitance method is done the result is a 1st order non- homogeneous differential equation with following solution. T(t)=b/a+(T0-b/a)exp(-at) Where T and t represent temperature and time, a , b and T0 are constants containing physical properties and initial conditions. MAJO POINTS i- Conducton and convection are dominant modes of heat transfer ii-Lumped capacitance method, although simple, provides reasonable first approaximation. The rsult indicates that diffuser wall average temperature varies from nozzle entrance through the length of the diffuser. The maximum appears 30-50 sec after the start of the test and varies from 710-940 R. This was part of the summer faculy fellowship at NASA SSC

Aceil, Sam

2000-11-01

213

Time-frequency analyses of transient-evoked stimulus-frequency and distortion-product otoacoustic emissions: Testing cochlear model predictions  

NASA Astrophysics Data System (ADS)

Time-frequency representations (TFRs) of otoacoustic emissions (OAEs) provide information simultaneously in time and frequency that may be obscured in waveform or spectral analyses. TFRs were applied to transient-evoked stimulus-frequency (SF) and distortion-product (DP) OAEs to test cochlear model predictions. SFOAEs and DPOAEs were elicited in 18 normal-hearing subjects using gated tones and tone pips. Synchronous spontaneous (SS) OAEs were measured to assess their contributions to SFOAEs and DPOAEs. A common form of TFR of measured OAEs was a collection of frequency-specific components often aligned with SSOAE sites, with each component characterized by one or more brief segments or a single long-duration segment. The spectral envelope of evoked OAEs differed from that of the evoking stimulus. Strong emission regions or cochlear ``hot spots'' were detected, and sometimes accounted for OAE energy observed outside the stimulus bandwidth. Contributions of hot spots and multiple internal reflections to the OAE, and differences between measured and predicted OAE spectra, increased as stimulus level decreased, consistent with level-dependent changes in the estimated cochlear reflectance. Suppression and frequency-pulling effects between components were observed. A recursive formulation was described for the linear coherent reflection emission theory [Zweig and Shera, J. Acoust. Soc. Am. 98, 2018-2047 (1995)] that is well suited for time-domain calculations.

Konrad-Martin, Dawn; Keefe, Douglas H.

2003-10-01

214

Acoustic Data Processing and Transient Signal Analysis for the Hybrid Wing Body 14- by 22-Foot Subsonic Wind Tunnel Test  

NASA Technical Reports Server (NTRS)

An advanced vehicle concept, the HWB N2A-EXTE aircraft design, was tested in NASA Langley's 14- by 22-Foot Subsonic Wind Tunnel to study its acoustic characteristics for var- ious propulsion system installation and airframe con gurations. A signi cant upgrade to existing data processing systems was implemented, with a focus on portability and a re- duction in turnaround time. These requirements were met by updating codes originally written for a cluster environment and transferring them to a local workstation while en- abling GPU computing. Post-test, additional processing of the time series was required to remove transient hydrodynamic gusts from some of the microphone time series. A novel automated procedure was developed to analyze and reject contaminated blocks of data, under the assumption that the desired acoustic signal of interest was a band-limited sta- tionary random process, and of lower variance than the hydrodynamic contamination. The procedure is shown to successfully identify and remove contaminated blocks of data and retain the desired acoustic signal. Additional corrections to the data, mainly background subtraction, shear layer refraction calculations, atmospheric attenuation and microphone directivity corrections, were all necessary for initial analysis and noise assessments. These were implemented for the post-processing of spectral data, and are shown to behave as expected.

Bahr, Christopher J.; Brooks, Thomas F.; Humphreys, William M.; Spalt, Taylor B.; Stead, Daniel J.

2014-01-01

215

Dislocation reduction in sulfur- and germanium-doped indium phosphide single crystals grown by the vertical gradient freeze process: A transient finite-element study  

NASA Astrophysics Data System (ADS)

During the growth of indium phosphide (InP) crystals, dislocations are mostly generated in a plastically deformed crystal due to crystallographic glide caused by excessive thermal stresses. High dislocation density presented in the InP crystal can reduce the performance, lifetime, and reliability of the InP-based microelectronic and optoelectronic devices/circuits. The generation of dislocations in InP single crystals grown from the melt can be predicted by using a transient finite-element model. This model couples microscopic dislocation motion and multiplication to macroscopic plastic deformation during the crystal growth process. The temperature fields in the crystal are determined by solving the partial differential equations of heat transfer for the vertical gradient freeze (VGF) process. These temperature fields are then employed to the transient finite-element model to study the effects of doping impurities and growth parameters (i.e., imposed temperature gradient, crystal radius, and growth rate) on dislocation reduction in InP crystals grown by different VGF processes.

Zhu, X. A.; Tsai, C. T.

2005-02-01

216

Qualification test procedures and results for Honeywell solar collector subsystem, single-family residence  

NASA Technical Reports Server (NTRS)

The test procedures and results in qualifying the Honeywell single family residence solar collector subsystem are presented. Testing was done in the following areas: pressure, service loads, hail, solar degradation, pollutants, thermal degradation, and outgassing.

1977-01-01

217

Tests of Lorentz symmetry in single beta decay  

E-print Network

Low-energy experiments studying single beta decay can serve as sensitive probes of Lorentz invariance that can complement interferometric searches for deviations from this spacetime symmetry. Experimental signatures of a dimension-three operator for Lorentz violation that are unobservable in neutrino oscillations are described for the decay the polarized and unpolarized neutrons as well as for measurements of the spectral endpoint in beta decay.

Diaz, Jorge S

2014-01-01

218

Soumis J Eur. Ceram. Soc. Intermediate temperature SOFC single cell test  

E-print Network

1 Soumis à J Eur. Ceram. Soc. Intermediate temperature SOFC single cell test using Nd1.95NiO4 Abstract This work deals with SOFC single cell tests using neodymium nickelate Nd1.95NiO4+ as cathode material. This MIEC oxide exhibits high values of both surface exchange coefficient (k) and oxygen

Boyer, Edmond

219

76 FR 34801 - Petition for Modification of Single Car Air Brake Test Procedures  

Federal Register 2010, 2011, 2012, 2013

...FRA-2010-0174] Petition for Modification of Single Car Air Brake Test Procedures In accordance...FRA) grant a modification of the single car air brake test procedures as prescribed...FRA-2010-0174. PATH operates a fleet of 25 flat cars in consist with revenue cars utilized...

2011-06-14

220

Results of the ETV-1 breadboard tests under steady-state and transient conditions. [conducted in the NASA-LeRC Road Load Simulator  

NASA Technical Reports Server (NTRS)

Steady state tests were run to characterize the system and component efficiencies over the complete speed-torque capabilities of the propulsion system in both motoring and regenerative modes of operation. The steady state data were obtained using a battery simulator to separate the effects on efficiency caused by changing battery state-of-charge and component temperature. Transient tests were performed to determine the energy profiles of the propulsion system operating over the SAE J227a driving schedules.

Sargent, N. B.; Dustin, M. O.

1981-01-01

221

Pressure transient testing of a manmade fractured geothermal reservoir: an examination of fracture versus matrix dominated flow effects  

SciTech Connect

The data analysis is in terms of a diffusion equation that determines the flow of water and hence the pressure in the main fracture system, associated joints, and the matrix permeability. The fits of the flow data to type curve solutions of the diffusion equation with pressure-dependent properties for various flow geometries are presented. The following points are considered in detail. (1) The limits on the fracture geometry, aperture, and diffusing areas are determined from the diffusion parameters. (2) Dependence of the parameters (impedance, diffusivity) of the flow-through systems are related to the inflation of the major fractures. (3) The rock properties are related to the reservoir compressibility and permeability. In particular, laboratory experiments have shown that the properties of all sizes of cracks from large single fractures to the microstructure are pressure dependent if the fluid pressure is near the confining stress. The effects of this pressure dependence on the form of the type curves are included. (4) The competition of flow into the various types of porosity (main fractures, joints, and microstructure) and the effect on the interpretation of type curves are considered. The approach described makes an important departure from conventional pressure-transient reservoir analysis in that pressure-dependent properties are incorporated into a numerically simulated generation of type curves resulting from one- and two-dimensional diffusion. In addition, the problem of specifying a unique flow geometry where both matrix and fracture-dominated, non-Darcy flow effects are possible is analyzed using a large amount of field and laboratory data in conjunction with a theoretical treatment that reviews the existing state of the art in reservoir mechanics.

Fisher, H.N.; Tester, J.W.

1980-09-01

222

Test procedures and instructions for single shell tank saltcake cesium removal with crystalline silicotitanate  

SciTech Connect

This document provides specific test procedures and instructions to implement the test plan for the preparation and conduct of a cesium removal test, using Hanford Single Shell Tank Saltcake from tanks 24 t -BY- I 10, 24 1 -U- 108, 24 1 -U- 109, 24 1 -A- I 0 1, and 24 t - S-102, in a bench-scale column. The cesium sorbent to be tested is crystalline siticotitanate. The test plan for which this provides instructions is WHC-SD-RE-TP-024, Hanford Single Shell Tank Saltcake Cesium Removal Test Plan.

Duncan, J.B.

1997-01-07

223

Dynamic tensile test of single PET textile cables  

NASA Astrophysics Data System (ADS)

The tyres conception involves for certain applications, the use of textile cables as reinforcement. During its use, the tyre undergoes temperatures variations and dynamic loading rates. The consideration of these conditions during the numeric simulations requires the knowledge of the sensitivity of the mechanical behaviour to loading rate and temperature. In this paper, we developed an experimental methodology for testing textile cable up to high strain rate. The main difficulty of testing cables is the optimization of cable fixing on the machine. For that purpose, we adapted the solution of fixing by progressive binding already used in quasi-static, while taking into account constraints inherent to high strain tests. Firstly, the mass of grips was decreased in order to get force signal less sensitive to grips inertia. The method was developed on a high speed hydraulic machine equipped with a thermal enclosure. The investigated temperatures and strain rates range from room temperature to 373 ?K (100 ?C) and from 0,01 to 100/s, respectively. In addition, the hydraulic machine was equipped with a high speed video camera. The obtained images were analysed by a tracking technique to measure the average strain in the cable (from 50 to 20000 f/s).

Guégan, P.; Othman, R.; Pasco, F.; Bruant, R.

2012-08-01

224

The utility of a single test to identify women at risk for gestational diabetes  

Microsoft Academic Search

A number of single tests have been proposed as both screening and definitive tests of glucose intolerance during pregnancy.\\u000a Despite limitations imposed by a lack of uniformity in methodology and definitions of gestational diabetes mellitus, there\\u000a appears to be an independent relationship between some single-test results and clinically meaningful outcomes. Further study\\u000a is needed to identify those glucose values above

David A. Sacks

2001-01-01

225

DESIGN AND PERFORMANCE OBJECTIVES OF THE SINGLE CELL TEST SYSTEM FOR SO2 DEPOLARIZED ELECTROLYZER DEVELOPMENT  

SciTech Connect

The single cell test system development for the SRNL sulfur dioxide-depolarized electrolyzer has been completed. Operating experience and improved operating procedures were developed during test operations in FY06 and the first quarter of FY07. Eight different cell configurations, using various MEA designs, have been tested. The single cell test electrolyzer has been modified to overcome difficulties experienced during testing, including modifications to the inlet connection to eliminate minute acid leaks that caused short circuits. The test facility was modified by adding a water bath for cell heating, thus permitting operation over a wider range of flowrates and cell temperatures. Modifications were also identified to permit continuous water flushing of the cathode to remove sulfur, thus extending operating time between required shutdowns. This is also expected to permit a means of independently measuring the rate of sulfur formation, and the corresponding SO{sub 2} flux through the membrane. This report contains a discussion of the design issues being addressed by the single cell test program, a test matrix being conducted to address these issues, and a summary of the performance objectives for the single cell test system. The current primary objective of single cell test system is to characterize and qualify electrolyzer configurations for the following 100-hour longevity tests. Although the single cell test system development is considered complete, SRNL will continue to utilize the test facility and the single cell electrolyzer to measure the operability and performance of various cell design configurations, including new MEA's produced by the component development tasks.

Steimke, J

2007-01-15

226

Parametric Testing of Chevrons on Single Flow Hot Jets  

NASA Technical Reports Server (NTRS)

A parametric family of chevron nozzles have been studied, looking for relationships between chevron geometric parameters, flow characteristics, and far-field noise. Both cold and hot conditions have been run at acoustic Mach number 0.9. Ten models have been tested, varying chevron count, penetration, length, and chevron symmetry. Four comparative studies were defined from these datasets which show: that chevron length is not a major impact on either flow or sound; that chevron penetration increases noise at high frequency and lowers it at low frequency, especially for low chevron counts; that chevron count is a strong player with good low frequency reductions being achieved with high chevron count without strong high frequency penalty; and that chevron asymmetry slightly reduces the impact of the chevron. Finally, it is shown that although the hot jets differ systematically from the cold one, the overall trends with chevron parameters is the same.

Bridges, James; Brown, Clifford A.

2004-01-01

227

COMMIX-1AR/P: A three-dimensional transient single-phase computer program for thermal hydraulic analysis of single and multicomponent systems. Volume 3, Programmer`s guide  

SciTech Connect

The COMMIX-LAR/P computer program is designed for analyzing the steady-state and transient aspects of single-phase fluid flow and heat transfer in three spatial dimensions. This version is an extension of the modeling in COMMIX-lA to include multiple fluids in physically separate regions of the computational domain, modeling descriptions for pumps, radiation heat transfer between surfaces of the solids which are embedded in or surround the fluid, a keg model for fluid turbulence, and improved numerical techniques. The porous-medium formulation in COMMIX allows the program to be applied to a wide range of problems involving both simple and complex geometrical arrangements. The internal aspects of the COMMIX-LAR/P program are presented, covering descriptions of subprograms, variables, and files.

Garner, P.L.; Blomquist, R.N.; Gelbard, E.M.

1992-09-01

228

COMMIX-1AR/P: A three-dimensional transient single-phase computer program for thermal hydraulic analysis of single and multicomponent systems. Volume 2, User`s guide  

SciTech Connect

The COMMIX-1AR/P computer program is designed for analyzing the steady-state and transient aspects of single-phase fluid flow and heat transfer in three spatial dimensions. This version is an extension of the modeling in COMMIX-1A to include multiple fluids in physically separate regions of the computational domain, modeling descriptions for pumps, radiation heat transfer between surfaces of the solids which are embedded in or surround the fluid, a k-{var_epsilon} model for fluid turbulence, and improved numerical techniques. The porous-medium formulation in COMMIX allows the program to be applied to a wide range of problems involving both simple and complex geometrical arrangements. The input preparation and execution procedures are presented for the COMMIX-1AR/P program and several postprocessor programs which produce graphical displays of the calculated results.

Garner, P.L.; Blomquist, R.N.; Gelbard, E.M.

1992-09-01

229

Advanced development of the spectrum sciences Model 5005-TF, single-event test fixture  

SciTech Connect

This report summarizes the advanced development of the Spectrum Sciences Model 5005-TF, Single-Event Test Fixture. The Model 5005-TF uses a Californium-252 (Cf-252) fission-fragment source to test integrated circuits and other devices for the effects of single-event phenomena. Particle identification methods commonly used in high-energy physics research and nuclear engineering have been incorporated into the Model 5005-TF for estimating the particle charge, mass, and energy parameters. All single-event phenomena observed in a device under test (DUT) are correlated with an identified fission fragment, and its linear energy transfer (LET) and range in the semiconductor material of the DUT.

Ackermann, M.R.; Browning, J.S. (Sandia National Labs., Albuquerque, NM (USA)); Hughlock, B.W. (Boeing Aerospace and Electronics Co., Seattle, WA (USA)); Lum, G.K. (Lockheed Missiles and Space Co., Sunnyvale, CA (USA)); Tsacoyeanes, W.C. (Draper (Charles Stark) Lab., Inc., Cambridge, MA (USA)); Weeks, M.D. (Spectrum Sciences, Inc., Santa Clara, CA (USA))

1990-09-01

230

Design and testing of a high accuracy robotic single-cell manipulator  

E-print Network

We have designed, built and tested a high accuracy robotic single-cell manipulator to be able to pick individual cells from array of microwells, each 30 Pm or 50 pm cubed. Design efforts have been made for higher accuracy, ...

Yoon, Jun Young, S.M. Massachusetts Institute of Technology

2011-01-01

231

Direct comparison of charge collection from single-photon and two-photon laser testing techniques.  

SciTech Connect

The amounts of charge collection by single-photon absorption to that by two-photon absorption laser testing techniques have been directly compared using specially made SOI diodes. Details of this comparison are discussed.

Ferlet-Cavrois, Veronique (ESA/ESTEC); Dalton, Scott Matthew; Stevens, Jeffrey; Flores, Richard S.; Gouker, Pascale M. (MIT Lincoln Laboratory); Schwank, James Ralph; McMorrow, Dale (Naval Research Laboratory); Swanson, Scot E.; Shaneyfelt, Marty Ray; Dodd, Paul Emerson; Vizkelethy, Gyorgy

2010-03-01

232

Reconsidering association testing methods using single-variant test statistics as alternatives to pooling tests for sequence data with rare variants.  

PubMed

Association tests that pool minor alleles into a measure of burden at a locus have been proposed for case-control studies using sequence data containing rare variants. However, such pooling tests are not robust to the inclusion of neutral and protective variants, which can mask the association signal from risk variants. Early studies proposing pooling tests dismissed methods for locus-wide inference using nonnegative single-variant test statistics based on unrealistic comparisons. However, such methods are robust to the inclusion of neutral and protective variants and therefore may be more useful than previously appreciated. In fact, some recently proposed methods derived within different frameworks are equivalent to performing inference on weighted sums of squared single-variant score statistics. In this study, we compared two existing methods for locus-wide inference using nonnegative single-variant test statistics to two widely cited pooling tests under more realistic conditions. We established analytic results for a simple model with one rare risk and one rare neutral variant, which demonstrated that pooling tests were less powerful than even Bonferroni-corrected single-variant tests in most realistic situations. We also performed simulations using variants with realistic minor allele frequency and linkage disequilibrium spectra, disease models with multiple rare risk variants and extensive neutral variation, and varying rates of missing genotypes. In all scenarios considered, existing methods using nonnegative single-variant test statistics had power comparable to or greater than two widely cited pooling tests. Moreover, in disease models with only rare risk variants, an existing method based on the maximum single-variant Cochran-Armitage trend chi-square statistic in the locus had power comparable to or greater than another existing method closely related to some recently proposed methods. We conclude that efficient locus-wide inference using single-variant test statistics should be reconsidered as a useful framework for devising powerful association tests in sequence data with rare variants. PMID:22363423

Kinnamon, Daniel D; Hershberger, Ray E; Martin, Eden R

2012-01-01

233

Defensive Burying as a Function of Single-and Paired-Animal Testing Conditions  

Microsoft Academic Search

Studied the relationship between single- and paired-animal testing in the defensive-burying situation. Twenty male Holtzman rats received defensive burying testing both individually and in pairs. Testing took place in a rectangular enclosure having a bedding-material floor. The discharge of a flashbulb served as the aversive stimulus. Individual testing resulted in significantly (p < .01) longer burying durations and greater accumulation

Stephen F. Davis; David A. Whiteside; Douglas G. Heck; Cynthia L. Cowen

1982-01-01

234

First high power pulsed tests of a dressed 325 MHz superconducting single spoke resonator at Fermilab  

SciTech Connect

In the recently commissioned superconducting RF cavity test facility at Fermilab (SCTF), a 325 MHz, {beta} = 0.22 superconducting single-spoke resonator (SSR1) has been tested for the first time with its input power coupler. Previously, this cavity had been tested CW with a low power, high Q{sub ext} test coupler; first as a bare cavity in the Fermilab Vertical Test Stand and then fully dressed in the SCTF. For the tests described here, the design input coupler with Q{sub ext} {approx} 10{sup 6} was used. Pulsed power was provided by a Toshiba E3740A 2.5 MW klystron.

Madrak, R.; Branlard, J.; Chase, B.; Darve, C.; Joireman, P.; Khabiboulline, T.; Mukherjee, A.; Nicol, T.; Peoples-Evans, E.; Peterson, D.; Pischalnikov, Y.; /Fermilab

2011-03-01

235

Modeling Single Well Injection-Withdrawal (SWIW) Tests for Characterization of Complex Fracture-Matrix Systems  

Microsoft Academic Search

An essential condition for performance evaluation of enhanced geothermal systems (EGS) resides in the ability to reliably predict fluid flow and heat transport in fractured porous rocks, where fast convection-dispersive transport through the fracture network can be strongly affected by heat conduction into the adjacent rock matrix. SWIW tests are single-well tracer tests that involve an initial period of fluid

F. P. Cotte; C. Doughty; J. T. Birkholzer

2010-01-01

236

The Development and Validation of a Formula for Measuring Single-Sentence Test Item Readability.  

ERIC Educational Resources Information Center

A study was conducted with 782 elementary school students to determine whether the Homan-Hewitt Readability Formula could identify the readability of a single-sentence test item. Results indicate that a relationship exists between students' reading grade levels and responses to test items written at higher readability levels. (SLD)

Homan, Susan; And Others

1994-01-01

237

Analytical solutions for efficient interpretation of single-well push-pull tracer tests  

EPA Science Inventory

Single-well push-pull tracer tests have been used to characterize the extent, fate, and transport of subsurface contamination. Analytical solutions provide one alternative for interpreting test results. In this work, an exact analytical solution to two-dimensional equations descr...

238

Efficiency of 3 single-harvest tests for evaluation of yield in pickling cucumber  

Microsoft Academic Search

Three rapid tests for measuring yield (small plots harvested once-over, and single plants harvested at the green and at the mature fruit stage) of pickling cucumber (Cucumis sativus L.) were evaluated for efficiency compared with the standard multiple-harvest trial with 2 or 3 replications and large plots. Fifteen genotypes were tested in 1981 and 18 in 1982 to determine the

Todd C. Wehner

1986-01-01

239

A Nuclear Interaction Model for Understanding Results of Single Event Testing with High Energy Protons  

NASA Technical Reports Server (NTRS)

An internuclear cascade and evaporation model has been adapted to estimate the LET spectrum generated during testing with 200 MeV protons. The model-generated heavy ion LET spectrum is compared to the heavy ion LET spectrum seen on orbit. This comparison is the basis for predicting single event failure rates from heavy ions using results from a single proton test. Of equal importance, this spectra comparison also establishes an estimate of the risk of encountering a failure mode on orbit that was not detected during proton testing. Verification of the general results of the model is presented based on experiments, individual part test results, and flight data. Acceptance of this model and its estimate of remaining risk opens the hardware verification philosophy to the consideration of radiation testing with high energy protons at the board and box level instead of the more standard method of individual part testing with low energy heavy ions.

Culpepper, William X.; ONeill, Pat; Nicholson, Leonard L.

2000-01-01

240

A single electromyographic testing point is valid to monitor neuromuscular fatigue during continuous exercise.  

PubMed

Two different protocols for estimating the electromyographic fatigue threshold (EMGFT) have been proposed in the literature. These protocols are distinguished by the number of visits required to determine the EMGFT. The purpose of this study, therefore, was to statistically compare the estimated EMGFT from the single-visit incremental test and the multiple-visit constant workload tests for single-leg knee-extensor exercise. Seven healthy college-aged men [mean ± SEM; age = 25.0 ± 0.7 years] performed the incremental test and on separate occasions also performed 4 constant workload tests to voluntary exhaustion. The EMG amplitude was recorded from the rectus femoris muscle during all the testing sessions. For the single-visit test, the EMG amplitude vs. time relationship for each power output was examined using linear regression. For the multiple-visit tests, the EMG amplitude vs. time relationship was calculated for each constant power output. Thereafter, the power outputs were plotted as a function of the slope coefficient for the EMG amplitude vs. time relationships, and linear regression was performed. The EMGFT was defined as the intersection of the regression line with the y-intercept of the power output vs. slope coefficient plot. The results indicated that the estimated EMGFT from the single-visit test was significantly (p = 0.012) lower than the estimate from the multiple-visit tests. Because this test is performed during a single visit and concludes within 20 minutes, it may also have application in clinical rehabilitation settings and not merely for an athletic population. PMID:25029004

Galen, Sujay S; Malek, Moh H

2014-10-01

241

A Switching Surge Transient Recording Device  

Microsoft Academic Search

A switching surge transient recording device has been designed, built, and tested which serves as a continuous, unattended monitor of power system switching transients. Rather than reproduce the transient waveform, the recorder senses and records the positive and negative peak magnitudes of the transient to within a 4.0 per unit overvoltage limit, the maximum positive and maximum negative rates of

Dean Perry; Richard Raupach; C. A. E. Uhlig

1968-01-01

242

Numerical study of the SSME nozzle flow fields during transient operations: A comparison of the animated results with test  

Microsoft Academic Search

A computational fluid dynamics (CFD) model has been applied to study the transient flow phenomena of the nozzle and exhaust plume of the Space Shuttle Main Engine (SSME), fired at sea level. The CFD model is a time accurate, pressure based, reactive flow solver. A six-species hydrogen\\/oxygen equilibrium chemistry is used to describe the chemical-thermodynamics. An adaptive upwinding scheme is

Ten-See Wang; Catherine Dumas

1993-01-01

243

Space Power Facility-Capabilities for Space Environmental Testing Within a Single Facility  

NASA Technical Reports Server (NTRS)

The purpose of this paper is to describe the current and near-term environmental test capabilities of the NASA Glenn Research Center's Space Power Facility (SPF) located at Sandusky, Ohio. The paper will present current and near-term capabilities for conducting electromagnetic interference and compatibility testing, base-shake sinusoidal vibration testing, reverberant acoustic testing, and thermal-vacuum testing. The paper will also present modes of transportation, handling, ambient environments, and operations within the facility to conduct those tests. The SPF is in the midst of completing and activating new or refurbished capabilities which, when completed, will provide the ability to conduct most or all required full-scale end-assembly space simulation tests at a single test location. It is envisioned that the capabilities will allow a customer to perform a wide range of space simulation tests in one facility at reasonable cost.

Sorge, Richard N.

2013-01-01

244

Determination of surface heat flux using a single embedded thermocouple  

NASA Technical Reports Server (NTRS)

An implicit numerical procedure was developed for predicting the transient heat flux to a material using a single embedded thermocouple. The accuracy of the method was demonstrated by comparisons with analytically generated test data.

Williams, S. D.; Curry, D. M.

1976-01-01

245

Transient performance  

NASA Astrophysics Data System (ADS)

Gas turbine engine transient behavior, that which is concerned with the changes in engine parameters during acceleration or decceleration of an engine from one steady state point to a different steady state point, is considered. An engine can also experience cyclic aerodynamic phenomena which occur at a nominally steady condition; examples are compressor rotator stall and intake or afterburner buzz. The following are discussed: certification requirements; mechanism of acceleration; compressor working lines and surge; and some important factors (pressure level, moment of inertia, heat soakage, clearances, measurement of transients, thrust reversal, and transient maneuvers which involve significant changes to the shaft speeds of the engine). A set of graphics illustrating transient performance is presented.

Curnock, Barry

246

Comparative Performance of Four Single Extreme Outlier Discordancy Tests from Monte Carlo Simulations  

PubMed Central

Using highly precise and accurate Monte Carlo simulations of 20,000,000 replications and 102 independent simulation experiments with extremely low simulation errors and total uncertainties, we evaluated the performance of four single outlier discordancy tests (Grubbs test N2, Dixon test N8, skewness test N14, and kurtosis test N15) for normal samples of sizes 5 to 20. Statistical contaminations of a single observation resulting from parameters called ? from ±0.1 up to ±20 for modeling the slippage of central tendency or ? from ±1.1 up to ±200 for slippage of dispersion, as well as no contamination (? = 0 and ? = ±1), were simulated. Because of the use of precise and accurate random and normally distributed simulated data, very large replications, and a large number of independent experiments, this paper presents a novel approach for precise and accurate estimations of power functions of four popular discordancy tests and, therefore, should not be considered as a simple simulation exercise unrelated to probability and statistics. From both criteria of the Power of Test proposed by Hayes and Kinsella and the Test Performance Criterion of Barnett and Lewis, Dixon test N8 performs less well than the other three tests. The overall performance of these four tests could be summarized as N2?N15 > N14 > N8. PMID:24737992

Diaz-Gonzalez, Lorena; Quiroz-Ruiz, Alfredo

2014-01-01

247

Ambiguity in measuring matrix diffusion with single-well injection/recovery tracer tests  

USGS Publications Warehouse

Single-well injection/recovery tracer tests are considered for use in characterizing and quantifying matrix diffusion in dual-porosity aquifers. Numerical modeling indicates that neither regional drift in homogeneous aquifers, nor heterogeneity in aquifers having no regional drift, nor hydrodynamic dispersion significantly affects these tests. However, when drift is coupled simultaneously with heterogeneity, they can have significant confounding effects on tracer return. This synergistic effect of drift and heterogeneity may help explain irreversible flow and inconsistent results sometimes encountered in previous single-well injection/recovery tracer tests. Numerical results indicate that in a hypothetical single-well injection/recovery tracer test designed to demonstrate and measure dual-porosity characteristics in a fractured dolomite, the simultaneous effects of drift and heterogeneity sometimes yields responses similar to those anticipated in a homogeneous dual-porosity formation. In these cases, tracer recovery could provide a false indication of the occurrence of matrix diffusion. Shortening the shut-in period between injection and recovery periods may make the test less sensitive to drift. Using multiple tracers having different diffusion characteristics, multiple tests having different pumping schedules, and testing the formation at more than one location would decrease the ambiguity in the interpretation of test data.

Lessoff, S. C.; Konikow, L. F.

1997-01-01

248

Columbia University flow instability experimental program: Volume 7. Single tube tests, critical heat flux test program  

SciTech Connect

This report deals with critical heat flux (CHF) measurements in vertical down flow of water at low pressures in a round Inconel tube, 96 inches long and 0.62 inch inside diameter. A total of 28 CHF points were obtained. These data were found to correlate linearly with the single variable q, defined as the heat flux required to raise the enthalpy from the inlet value to the saturation value. These results were compared to the published results of Swedish investigators for vertical upflow of water at low pressures in round tubes of similar diameters and various lengths. The parameter q depends on the inlet enthalpy and is a nonlocal variable, thus this correlation is nonlocal unless the coefficients depend upon tube length in a particular prescribed manner. For the low pressure Swedish data, the coefficients are practically independent of length and hence the correlation is nonlocal. In the present investigation only one length was employed, so it is not possible to determine whether the correlation for these data is local or nonlocal, although there is reason to believe that it is local. The same correlation was applied to a large data base (thousands of CHF points) compiled from the published data of a number of groups and found to apply, with reasonable accuracy over a wide range of conditions, yielding sometimes local and sometimes nonlocal correlations. The basic philosophy of data analysis here was not to generate a single correlation which would reproduce all data, but to search for correlations which apply adequately over some range and which might have some mechanistic significance. The tentative conclusion is that at least two mechanisms appear operative, leading to two types of correlations, one local, the other nonlocal.

Dougherty, T.; Maciuca, C.; McAssey, E.V. Jr.; Reddy, D.G.; Yang, B.W.

1992-09-01

249

Microscale material testing of single crystalline silicon: process effects on surface morphology and tensile strength  

Microsoft Academic Search

The mechanical properties of single-crystalline silicon are measured by uniaxial tension tests from microscale beam specimens patterned by four different common silicon etchants — KOH, EDP, TMAH and XeF2. SOI wafers are used to prepare test samples, which are 3–5 ?m thick, 20–100 ?m wide, and 6 mm long beam specimens; these are monolithically mounted on a temporary frame. A

Taechung Yi; Lu Li; Chang-Jin Kim

2000-01-01

250

Value of a Single-Tube Widal Test in Diagnosis of Typhoid Fever in Vietnam  

Microsoft Academic Search

The diagnostic value of an acute-phase single-tube Widal test for suspected typhoid fever was evaluated with 2,000 Vietnamese patients admitted to an infectious disease referral hospital between 1993 and 1998. Test patients had suspected typhoid fever and a blood culture positive for Salmonella typhi (n5 1,400) or Salmonella paratyphi A( n 5 45). Control patients had a febrile illness for

CHRISTOPHER M. PARRY; NGUYEN THI; TUYET HOA; JOHN WAIN; NGUYEN TRAN CHINH; TRAN TINH HIEN; NICHOLAS J. WHITE; JEREMY J. FARRAR

1999-01-01

251

In-flight and ground testing of single event upset sensitivity in static RAMs  

SciTech Connect

This paper presents the results from in-flight measurements of single event upsets (SEU) in static random access memories (SRAM) caused by the atmospheric radiation environment at aircraft altitudes. The memory devices were carried on commercial airlines at high altitude and mainly high latitudes. The SEUs were monitored by a Component Upset Test Equipment (CUTE), designed for this experiment. The in flight results are compared to ground based testing with neutrons from three different sources.

Johansson, K.; Dyreklev, P.; Granbom, B. [Ericsson Saab Avionics AB, Linkoeping (Sweden)] [Ericsson Saab Avionics AB, Linkoeping (Sweden); Calvet, C. [Aerospatiale Space and Defence, Les Mureaux (France)] [Aerospatiale Space and Defence, Les Mureaux (France); Fourtine, S. [Aerospatiale Avions, Toulouse (France)] [Aerospatiale Avions, Toulouse (France); Feuillatre, O. [Dassault Electronique, Saint-Cloud (France)] [Dassault Electronique, Saint-Cloud (France)

1998-06-01

252

Single-tier testing with the C6 peptide ELISA kit compared with two-tier testing for Lyme disease.  

PubMed

For the diagnosis of Lyme disease, the 2-tier serologic testing protocol for Lyme disease has a number of shortcomings including low sensitivity in early disease; increased cost, time, and labor; and subjectivity in the interpretation of immunoblots. In this study, the diagnostic accuracy of a single-tier commercial C6 ELISA kit was compared with 2-tier testing. The results showed that the C6 ELISA was significantly more sensitive than 2-tier testing with sensitivities of 66.5% (95% confidence interval [CI] 61.7-71.1) and 35.2% (95% CI 30.6-40.1), respectively (P < 0.001) in 403 sera from patients with erythema migrans. The C6 ELISA had sensitivity statistically comparable to 2-tier testing in sera from Lyme disease patients with early neurologic manifestations (88.6% versus 77.3%, P = 0.13) or arthritis (98.3% versus 95.6%, P = 0.38). The specificities of C6 ELISA and 2-tier testing in over 2200 blood donors, patients with other conditions, and Lyme disease vaccine recipients were found to be 98.9% and 99.5%, respectively (P < 0.05, 95% CI surrounding the 0.6 percentage point difference of 0.04 to 1.15). In conclusion, using a reference standard of 2-tier testing, the C6 ELISA as a single-step serodiagnostic test provided increased sensitivity in early Lyme disease with comparable sensitivity in later manifestations of Lyme disease. The C6 ELISA had slightly decreased specificity. Future studies should evaluate the performance of the C6 ELISA compared with 2-tier testing in routine clinical practice. PMID:23062467

Wormser, Gary P; Schriefer, Martin; Aguero-Rosenfeld, Maria E; Levin, Andrew; Steere, Allen C; Nadelman, Robert B; Nowakowski, John; Marques, Adriana; Johnson, Barbara J B; Dumler, J Stephen

2013-01-01

253

Use of the single-breath method of estimating cardiac output during exercise-stress testing.  

NASA Technical Reports Server (NTRS)

The single-breath cardiac output measurement technique of Kim et al. (1966) has been modified for use in obtaining cardiac output measurements during exercise-stress tests on Apollo astronauts. The modifications involve the use of a respiratory mass spectrometer for data acquisition and a digital computer program for data analysis. The variation of the modified method for triplicate steady-state cardiac output measurements was plus or minus 1 liter/min. The combined physiological and methodological variation seen during a set of three exercise tests on a series of subjects was 1 to 2.5 liter/min. Comparison of the modified method with the direct Fick technique showed that although the single-breath values were consistently low, the scatter of data was small and the correlation between the two methods was high. Possible reasons for the low single-breath cardiac output values are discussed.

Buderer, M. C.; Rummel, J. A.; Sawin, C. F.; Mauldin, D. G.

1973-01-01

254

The characterization of carbon nanotube infused glass fibers by single filament fragmentation test methods  

NASA Astrophysics Data System (ADS)

Single filament fragmentation tests were completed for individual glass fibers with varying surface treatments and carbon nanostructure infusions. Fiber fragmentation was analyzed by embedding a single filament into a standard tensile interface, which provided shear stress transfer between a conventional epoxy resin system and the constituent filament. Established single filament fragmentation techniques were used to characterize fiber and interface properties. A novel method of comparing fibers is introduced by correlating bundle tow test results to fiber fragmentation critical length data to qualitatively relate fiber performance. Photoelastic birefringent stress fringes were processed at select fiber fragmentation locations to further characterize the fiber-resin, or fiber-carbon nanostructure-resin, interface. Overall, the performance matrix qualitative comparison method, coupled with stress fringe analysis, proved to be an effective means of qualitatively evaluating fiber and processing parameters, and efficiently identifies the most fruitful path forward for optimized fiber development.

Roach, Andrew Michael

255

Age and smoking dependency of the single-breath oxygen test in healthy subjects  

Microsoft Academic Search

Normal values for the standardized single breath oxygen test of Comroe and Fowler [2] were obtained in 106 males (38 smokers) and 48 females (non-smokers). There was a significant positive relationship between age and nitrogen gradient in male and female non-smokers, as well as in male smokers. No difference in the slope of the nitrogen gradient with age was observed

Dan C. St?nescu

1972-01-01

256

Initial Comparison of Single Cylinder Stirling Engine Computer Model Predictions with Test Results  

NASA Technical Reports Server (NTRS)

A Stirling engine digital computer model developed at NASA Lewis Research Center was configured to predict the performance of the GPU-3 single-cylinder rhombic drive engine. Revisions to the basic equations and assumptions are discussed. Model predictions with the early results of the Lewis Research Center GPU-3 tests are compared.

Tew, R. C., Jr.; Thieme, L. G.; Miao, D.

1979-01-01

257

SINGLE ELEMENT TEST PREDICTIONS FOR STRESS-STRAIN BEHAVIOR OF PANKI FLY-ASH  

E-print Network

1 SINGLE ELEMENT TEST PREDICTIONS FOR STRESS-STRAIN BEHAVIOR OF PANKI FLY-ASH M. Waseem1 , A: Fly-ash is a waste product produced by burning of coal at thermal power plants. It is often used as geo material for filling the low lying areas. Present study is conducted on F-class fly-ash from Panki

Prashant, Amit

258

ANALYSIS AND INTERPRETATION OF SINGLE-WELL TRACER TESTS IN STRATIFIED AQUIFERS  

EPA Science Inventory

The study deals with the definition and measurement of the dispersive properties of aquifers. Knowledge of such dispersive properties are of fundamental importance to the evaluation, analysis, and simulation of contaminant migration in groundwater. In the single-well test describ...

259

Infrastructure Development of Single Cell Testing Capability at A0 Facility  

Microsoft Academic Search

The objective of this technical note is to document the details of the infrastructure development process that was realized at the A0 photo injector facility to establish RF cold testing capability for 1.3 GHz superconducting niobium single cell cavities. The activity began the last quarter of CY 2006 and ended the first quarter of CY 2009. The whole process involved

Nandhini Dhanaraj; R. Padilla; J. Reid; T. Khabiboulline; M. Ge; A. Mukherjee; I. Rakhnov; C. Ginsburg; G. Wu; E. Harms; H. Carter

2009-01-01

260

Guideline for heavy ion radiation testing for Single Event Upset (SEU)  

SciTech Connect

A guideline for heavy ion radiation testing for single event upset was prepared to assist new experimenters in preparing and directing tests. How to estimate parts vulnerability and select an irradiation facility is described. A broad brush description of JPL equipment is given, certain necessary pre-test procedures are outlined and the roles and testing guidelines for on-site test personnel are indicated. Detailed descriptions of equipment needed to interface with JPL test crew and equipment are not provided, nor does it meet the more generalized and broader requirements of a MIL-STD document. A detailed equipment description is available upon request, and a MIL-STD document is in the early stages of preparation.

Nichols, D.K.; Price, W.E.; Malone, C.

1984-01-01

261

A guideline for heavy ion radiation testing for Single Event Upset (SEU)  

NASA Technical Reports Server (NTRS)

A guideline for heavy ion radiation testing for single event upset was prepared to assist new experimenters in preparing and directing tests. How to estimate parts vulnerability and select an irradiation facility is described. A broad brush description of JPL equipment is given, certain necessary pre-test procedures are outlined and the roles and testing guidelines for on-site test personnel are indicated. Detailed descriptions of equipment needed to interface with JPL test crew and equipment are not provided, nor does it meet the more generalized and broader requirements of a MIL-STD document. A detailed equipment description is available upon request, and a MIL-STD document is in the early stages of preparation.

Nichols, D. K.; Price, W. E.; Malone, C.

1984-01-01

262

MULTIMOMENT RADIO TRANSIENT DETECTION  

SciTech Connect

We present a multimoment technique for signal classification and apply it to the detection of fast radio transients in incoherently dedispersed data. Specifically, we define a spectral modulation index in terms of the fractional variation in intensity across a spectrum. A signal whose intensity is distributed evenly across the entire band has a lower modulation index than a spectrum whose intensity is localized in a single channel. We are interested in broadband pulses and use the modulation index to excise narrowband radio frequency interference by applying a modulation index threshold above which candidate events are removed. The technique is tested both with simulations and using data from known sources of radio pulses (RRAT J1928+15 and giant pulses from the Crab pulsar). The method is generalized to coherent dedispersion, image cubes, and astrophysical narrowband signals that are steady in time. We suggest that the modulation index, along with other statistics using higher order moments, should be incorporated into signal detection pipelines to characterize and classify signals.

Spitler, L. G.; Cordes, J. M.; Chatterjee, S. [Astronomy Department and NAIC, Cornell University, Ithaca, NY 14853 (United States); Stone, J., E-mail: lspitler@astro.cornell.edu [Department of Physics and Astronomy, Barnard College, New York, NY 10027 (United States)

2012-04-01

263

LUNAR OUTGASSING, TRANSIENT PHENOMENA, AND THE RETURN TO THE MOON. II. PREDICTIONS AND TESTS FOR OUTGASSING/REGOLITH INTERACTIONS  

SciTech Connect

We follow Paper I with predictions of how gas leaking through the lunar surface could influence the regolith, as might be observed via optical transient lunar phenomena (TLPs) and related effects. We touch on several processes, but concentrate on low and high flow rate extremes, which are perhaps the most likely. We model explosive outgassing for the smallest gas overpressure at the regolith base that releases the regolith plug above it. This disturbance's timescale and affected area are consistent with observed TLPs; we also discuss other effects. For slow flow, escape through the regolith is prolonged by low diffusivity. Water, found recently in deep magma samples, is unique among candidate volatiles, capable of freezing between the regolith base and surface, especially near the lunar poles. For major outgassing sites, we consider the possible accumulation of water ice. Over geological time, ice accumulation can evolve downward through the regolith. Depending on gases additional to water, regolith diffusivity might be suppressed chemically, blocking seepage and forcing the ice zone to expand to larger areas, up to km{sup 2} scales, again, particularly at high latitudes. We propose an empirical path forward, wherein current and forthcoming technologies provide controlled, sensitive probes of outgassing. The optical transient/outgassing connection, addressed via Earth-based remote sensing, suggests imaging and/or spectroscopy, but aspects of lunar outgassing might be more covert, as indicated above. TLPs betray some outgassing, but does outgassing necessarily produce TLPs? We also suggest more intrusive techniques from radar to in situ probes. Understanding lunar volatiles seems promising in terms of resource exploitation for human exploration of the Moon and beyond, and offers interesting scientific goals in its own right. Many of these approaches should be practiced in a pristine lunar atmosphere, before significant confusing signals likely to be produced upon humans returning to the Moon.

Crotts, Arlin P. S.; Hummels, Cameron [Department of Astronomy, Columbia University, Columbia Astrophysics Laboratory, 550 West 120th Street, New York, NY 10027 (United States)

2009-12-20

264

Tank selection for Light Duty Utility Arm (LDUA) system hot testing in a single shell tank  

SciTech Connect

The purpose of this report is to recommend a single shell tank in which to hot test the Light Duty Utility Arm (LDUA) for the Tank Waste Remediation System (TWRS) in Fiscal Year 1996. The LDUA is designed to utilize a 12 inch riser. During hot testing, the LDUA will deploy two end effectors (a High Resolution Stereoscopic Video Camera System and a Still/Stereo Photography System mounted on the end of the arm`s tool interface plate). In addition, three other systems (an Overview Video System, an Overview Stereo Video System, and a Topographic Mapping System) will be independently deployed and tested through 4 inch risers.

Bhatia, P.K.

1995-01-31

265

First high gradient test results of a dressed 325 MHz superconducting single spoke resonator at Fermilab  

E-print Network

A new superconducting RF cavity test facility has been commissioned at Fermilab in conjunction with first tests of a 325 MHz, {\\beta} = 0.22 superconducting single-spoke cavity dressed with a helium jacket and prototype tuner. The facility is described and results of full gradient, CW cavity tests with a high Qext drive coupler are reported. Sensitivities to Q disease and externally applied magnetic fields were investigated. Results are compared to bare cavity results obtained prior to hydrogen degassing and welding into the helium jacket.

Webber, R C; Madrak, R; Nicol, T; Ristori, L; Soyars, W; Wagner, R

2012-01-01

266

Analytical solutions for efficient interpretation of single-well push-pull tracer tests  

NASA Astrophysics Data System (ADS)

Single-well push-pull tracer tests have been used to characterize the extent, fate, and transport of subsurface contamination. Analytical solutions provide one alternative for interpreting test results. In this work, an exact analytical solution to two-dimensional equations describing the governing processes acting on a dissolved compound during a modified push-pull test (advection, longitudinal and transverse dispersion, first-order decay, and rate-limited sorption/partitioning in steady, divergent, and convergent flow fields) is developed. The coupling of this solution with inverse modeling to estimate aquifer parameters provides an efficient methodology for subsurface characterization. Synthetic data for single-well push-pull tests are employed to demonstrate the utility of the solution for determining (1) estimates of aquifer longitudinal and transverse dispersivities, (2) sorption distribution coefficients and rate constants, and (3) non-aqueous phase liquid (NAPL) saturations. Employment of the solution to estimate NAPL saturations based on partitioning and non-partitioning tracers is designed to overcome limitations of previous efforts by including rate-limited mass transfer. This solution provides a new tool for use by practitioners when interpreting single-well push-pull test results.

Huang, Junqi; Christ, John A.; Goltz, Mark N.

2010-08-01

267

Distinction between persistent and transient infection in a bovine viral diarrhoea (BVD) control programme: appropriate interpretation of real-time RT-PCR and antigen-ELISA test results.  

PubMed

Control of bovine viral diarrhoea (BVD) in Belgium is currently implemented on a voluntary basis at herd level and mainly relies on detection and culling of persistently infected (PI) animals. The present field study was conducted during the winter of 2010/2011 to assess the performances of diagnostic assays used in the testing scheme for BVD as proposed by the two Belgian regional laboratories. Individual blood samples were collected from 4972 animals, and individual samples from the same herd were pooled (maximum of 30 individual samples per pool) and screened for the presence of Bovine Viral Diarrhoea Virus (BVDV)-specific RNA using a commercial real-time RT-PCR test (ADIAGENE). Individual samples from positive pools were then tested in parallel with the same RT-PCR test and with an antigen-capture ELISA test (IDEXX) to detect viremic animals. This study demonstrated that individual results differed according to the type of assay used (P < 0.001): 140 animals (2.8%) were positive by RT-PCR and 72 (1.4%) by antigen-ELISA. A second blood sample was taken 40 days later from 74 PCR positive animals to detect persistent viremia: 17 (23%) of these were still PCR positive and considered to be PI and the 57 that no longer tested positive were assumed to be transiently infected (TI) animals. All PI animals were positive also by antigen-ELISA at both time points. Among TI animals, 10 (16%) were positive by antigen-ELISA at the first but none at the second sampling. A highly significant difference in cycle threshold (Ct ) values obtained by RT-PCR was observed between PI and TI animals. ROC analysis was performed to establish thresholds to confirm with high probability that an animal is PI, based on the result of RT-PCR test performed on a single individual blood sample. PMID:23009318

Hanon, J-B; Van der Stede, Y; Antonissen, A; Mullender, C; Tignon, M; van den Berg, T; Caij, B

2014-04-01

268

Testing the Kerr-nature of stellar-mass black hole candidates by combining the continuum-fitting method and the power estimate of transient ballistic jets  

E-print Network

Astrophysical black hole candidates are thought to be the Kerr black holes predicted by General Relativity, as these objects cannot be explained otherwise without introducing new physics. However, there is no observational evidence that the space-time around them is really described by the Kerr solution. The Kerr black hole hypothesis can be tested with the already available X-ray data by extending the continuum-fitting method, a technique currently used by astronomers to estimate the spins of stellar-mass black hole candidates. In general, we cannot put a constraint on possible deviations from the Kerr geometry, but only on some combination between these deviations and the spin. The measurement of the radio power of transient jets in black hole binaries can potentially break this degeneracy, thus allowing for testing the Kerr-nature of these objects.

Cosimo Bambi

2012-01-08

269

Single-well interference slug tests to assess the vertical hydraulic conductivity of unconsolidated aquifers  

NASA Astrophysics Data System (ADS)

SummaryMeaningful understanding of flow and solute transport in general requires the knowledge of hydraulic conductivity and its anisotropy. Various field methods allow the measurement of the horizontal component (Kh), but vertical hydraulic conductivity (Kv) is rarely measured, for lack of practical field tests. This paper proposes vertical interference slug tests, an adaptation of inter-well interference slug tests to a single well, for the efficient field measurement of Kv. The test is carried out in a single well between a stress and an observation interval that are vertically isolated with a three-packer assembly. An instantaneous pressure pulse is induced in the stress interval and resulting drawdowns are recorded in both the stress and the observation intervals. In a proof-of-concept field study, 12 vertical interference tests were carried out sequentially along a fully-screened well across a moderately heterogeneous and highly anisotropic aquifer made up of littoral silts and sands. A direct-push method was used to install the well, which was completed without sand-pack to allow the natural collapse of sediments in the thin annular space around the screen. Direct-push wells allow the measurement of in situ hydraulic properties of sediments and minimize well construction interferences with hydraulic tests. Drawdowns measured in stress and observation intervals of multiple tests were simultaneously inverted numerically to reconstruct heterogeneous profiles of Kh, hydraulic conductivity anisotropy (Kv/Kh), and specific storage (Ss). Results were validated by comparison of observed versus predicted drawdowns and with field and laboratory measurements of Kh and Kv made along the tested well. Results indicate that the profile of Kv values obtained with vertical interference slug tests follows a similar pattern with depth than the profile with lab measurements made with a permeameter on soil samples collected in the same intervals as the interference tests, which demonstrates that vertical interference slug tests could provide an efficient method for the field measurement of well-scale Kv values.

Paradis, Daniel; Lefebvre, René

2013-01-01

270

Microsample testing of single crystalline Ti-52 at% Al and Ti-55.5 at% Al  

SciTech Connect

Dislocation activity in two-phase commercial TiAl alloys occurs most readily in the {gamma}-TiAl phase, and measurements of the CRSS of single crystalline {gamma}-TiAl provides a solid foundation for understanding the mechanical performance of these alloys. Single crystals of {gamma}-TiAl with greater than 54.5 at% Al have been grown using the optical float zone crystal growing technique, but single crystals with lower Al content, closer to that of commercial alloys, have not. In the present study, polycrystalline ingots of Ti-52 at% Al have been heat treated to form very large grains, and microsample tensile specimens, which have a nominal gage cross-section of 250{micro}m x 300{micro}m, a gage length of 250{micro}m and an overall length of 3 mm, have been machined from within single grains. Microsample high-temperature stress-strain curves for Ti-55.5 at% Al single crystals oriented along the [001] and [010] are presented. Tensile test results for Ti-52 at% Al tested at 1,073K along the[{bar 2}37], [{bar 1}73] and [{bar 3}44] orientations will also be discussed.

Zupan, M.; Dimiduk, D.M.; Hemker, K.J.

1999-07-01

271

High-pressure hydrogen testing of single crystal superalloys for advanced rocket engine turbopump turbine blades  

NASA Technical Reports Server (NTRS)

A screening program to determine the effects of high pressure hydrogen on selected candidate materials for advanced single crystal turbine blade applications is examined. The alloys chosen for the investigation are CM SX-2, CM SX-4C, Rene N-4, and PWA1480. Testing is carried out in hydrogen and helium at 34 MPa and room temperature, with both notched and unnotched single crystal specimens. Results show a significant variation in susceptibility to Hydrogen Environment Embrittlement (HEE) among the four alloys and a marked difference in fracture topography between hydrogen and helium environment specimens.

Alter, W. S.; Parr, R. A.; Johnston, M. H.; Strizak, J. P.

1984-01-01

272

Experimental Test of Theories of the Detection Mechanism in a Nanowire Superconducting Single Photon Detector  

NASA Astrophysics Data System (ADS)

We report an experimental test of the photodetection mechanism in a nanowire superconducting single photon detector. Detector tomography allows us to explore the 0.8-8 eV energy range via multiphoton excitations. High accuracy results enable a detailed comparison of the experimental data with theories for the mechanism of photon detection. We show that the temperature dependence of the efficiency of the superconducting single photon detector is determined not by the critical current but by the current associated with vortex unbinding. We find that both quasiparticle diffusion and vortices play a role in the detection event.

Renema, J. J.; Gaudio, R.; Wang, Q.; Zhou, Z.; Gaggero, A.; Mattioli, F.; Leoni, R.; Sahin, D.; de Dood, M. J. A.; Fiore, A.; van Exter, M. P.

2014-03-01

273

The dipole-flow test with a tracer: a new single-borehole tracer test for aquifer characterization  

NASA Astrophysics Data System (ADS)

We propose a new aquifer characterization test, the dipole-flow test with a tracer (DFTT), and develop its interpretation methodology. Combining the dipole-flow test (DFT) and a tracer test, the DFTT is a single-borehole, forced-gradient tracer test. The DFTT device isolates an injection and an extraction chamber in a well with inflatable packers and utilizes a small pump to create a dipole-flow pattern. After a steady-state flow field is reached and the pumping rate and chamber drawdowns are measured, a tracer is released into the injection chamber, and the concentration breakthrough curve is recorded in the extraction chamber. In developing the DFTT model, we assume that the aquifer is homogeneous on the scale of the test and that the well has no skin zone. We use a streamtube approach to semi-analytically simulate the tracer transport in a DFTT and determine the necessary relationships for estimating the longitudinal dispersivity as well as the radial and vertical hydraulic conductivities. The arrival time of the peak concentration is linearly related to the anisotropy ratio, and the arrival time of the tracer front is related to the longitudinal dispersivity. We present data from preliminary DFTTs conducted with Rhodamine WT (RWT) as a tracer at the Lizzie Field Site located between Farmville and Maury, NC. Our results demonstrate that this single-borehole tracer test is feasible and that its estimates of dispersivity are consistent with those reported in literature, whereas its estimates of hydraulic conductivity differ from the flowmeter-test estimates by less than an order of magnitude. This difference is most likely caused by the natural aquifer heterogeneity and different characterization scales of the two tests. The sorption of RWT and its composition of two differently sorbing isomers complicate the nature of the DFTT breakthrough curve and its interpretation. The use of a conservative tracer, such as bromide, should eliminate this complication. The skin effects readily manifest themselves in the DFTT breakthrough curve as extra and/or recirculated peaks. The presented interpretation methodology applies to cases with insignificant skin effects.

Sutton, D. J.; Kabala, Z. J.; Schaad, D. E.; Ruud, N. C.

2000-06-01

274

Transient-evoked and distortion product otoacoustic emissions: A short-term test-retest reliability study.  

PubMed

Knowledge regarding the variability of transient-evoked otoacoustic emissions (TEOAEs) and distortion product otoacoustic emissions (DPOAEs) is essential in clinical settings and improves their utility in monitoring hearing status over time. In the current study, TEOAEs and DPOAEs were measured with commercially available OAE-equipment in 56 normally-hearing ears during three sessions. Reliability was analysed for the retest measurement without probe-refitting, the immediate retest measurement with probe-refitting, and retest measurements after one hour and one week. The highest reliability was obtained in the retest measurement without probe-refitting, and decreased with increasing time-interval between measurements. For TEOAEs, the lowest reliability was seen at half-octave frequency bands 1.0 and 1.4 kHz; whereas for DPOAEs half-octave frequency band 8.0 kHz had also poor reliability. Higher primary tone level combination for DPOAEs yielded to a better reliability of DPOAE amplitudes. External environmental noise seemed to be the dominating noise source in normal-hearing subjects, decreasing the reliability of emission amplitudes especially in the low-frequency region. PMID:20151884

Keppler, Hannah; Dhooge, Ingeborg; Maes, Leen; D'haenens, Wendy; Bockstael, Annelies; Philips, Birgit; Swinnen, Freya; Vinck, Bart

2010-02-01

275

Atomic transient recorder  

Microsoft Academic Search

In Bohr's model of the hydrogen atom, the electron takes about 150 attoseconds (1 as = 10-18s) to orbit around the proton, defining the characteristic timescale for dynamics in the electronic shell of atoms. Recording atomic transients in real time requires excitation and probing on this scale. The recent observation of single sub-femtosecond (1fs = 10-15s) extreme ultraviolet (XUV) light

R. Kienberger; E. Goulielmakis; M. Uiberacker; A. Baltuska; V. Yakovlev; F. Bammer; A. Scrinzi; Th. Westerwalbesloh; U. Kleineberg; U. Heinzmann; M. Drescher; F. Krausz

2004-01-01

276

Hardy's paradox tested in the spin-orbit Hilbert space of single photons  

E-print Network

We test experimentally the quantum ``paradox'' proposed by Lucien Hardy in 1993 [Phys. Rev. Lett. 71, 1665 (1993)] by using single photons instead of photon pairs. This is achieved by addressing two compatible degrees of freedom of the same particle, namely its spin angular momentum, determined by the photon polarization, and its orbital angular momentum, a property related to the optical transverse mode. Because our experiment involves a single particle, we cannot use locality to logically enforce non-contextuality, which must therefore be assumed based only on the observables' compatibility. On the other hand, our single-particle experiment can be implemented more simply and allows larger detection efficiencies than typical two-particle ones, with a potential future advantage in terms of closing the detection loopholes.

Ebrahim Karimi; Filippo Cardano; Maria Maffei; Corrado de Lisio; Lorenzo Marrucci; Robert W. Boyd; Enrico Santamato

2014-03-22

277

Interpretation of transmissivity estimates from single-well pumping aquifer tests  

USGS Publications Warehouse

Interpretation of single-well tests with the Cooper-Jacob method remains more reasonable than most alternatives. Drawdowns from 628 simulated single-well tests where transmissivity was specified were interpreted with the Cooper-Jacob straight-line method to estimate transmissivity. Error and bias as a function of vertical anisotropy, partial penetration, specific yield, and interpretive technique were investigated for transmissivities that ranged from 10 to 10,000 m2/d. Cooper-Jacob transmissivity estimates in confined aquifers were affected minimally by partial penetration, vertical anisotropy, or analyst. Cooper-Jacob transmissivity estimates of simulated unconfined aquifers averaged twice the known values. Transmissivity estimates of unconfined aquifers were not improved by interpreting results with an unconfined aquifer solution. Judicious interpretation of late-time data consistently improved estimates where transmissivity exceeded 250 m2/d in unconfined aquifers. ?? 2006 National Ground Water Association.

Halford, K.J.; Weight, W.D.; Schreiber, R.P.

2006-01-01

278

Testing synthetic amyloid-? aggregation inhibitor using single molecule atomic force spectroscopy.  

PubMed

Alzheimer's disease is a neurodegenerative disease with no known cure and few effective treatment options. The principal neurotoxic agent is an oligomeric form of the amyloid-? peptide and one of the treatment options currently being studied is the inhibition of amyloid aggregation. In this work, we test a novel pseudopeptidic aggregation inhibitor designated as SG1. SG1 has been designed to bind at the amyloid-? self-recognition site and prevent amyloid-? from misfolding into ? sheet. We used atomic force spectroscopy, a nanoscale measurement technique, to quantify the binding forces between two single amyloid peptide molecules. For the first time, we demonstrate that single molecule atomic force spectroscopy can be used to assess the effectiveness of amyloid aggregation inhibitors by measuring the experimental yield of binding and can potentially be used as a screening technique for quick testing of efficacy of inhibitor drugs for amyloid aggregation. PMID:24321883

Hane, Francis T; Lee, Brenda Y; Petoyan, Anahit; Rauk, Arvi; Leonenko, Zoya

2014-04-15

279

High-Gradient Tests of the Single-Cell SC Cavity with a Feedback Waveguide  

SciTech Connect

Use of a superconducting (SC) traveling-wave accelerating (STWA) structure with a small phase advance per cell, rather than a standing-wave structure, may provide a significant increase in the accelerating gradient in the ILC linac [1]. For the same surface electric and magnetic fields, the STWA achieves an accelerating gradient 1.2 larger than TESLA-like standing-wave cavities. In addition, the STWA allows longer acceleration cavities, reducing the number of gaps between them. However, the STWA structure requires a SC feedback waveguide to return the few hundreds of MW of circulating RF power from the structure output to the structure input. A test single-cell cavity with feedback was designed and manufactured to demonstrate the possibility of proper processing to achieve a high accelerating gradient. The first results of high-gradient tests of a prototype 1.3 GHz single-cell cavity with feedback waveguide will be presented.

Yakovlev, V.; Solyak, N.; Wu, G.; Ge, M.; Gonin, I.; Khabiboulline, T.; Ozelis, J.; Rowe, A. [Fermilab, Batavia, IL 60510 (United States); Avrakhov, P.; Kanareykin, A. [Euclid TechLabs, LLC, Solon, Ohio 44139 (United States); Rathke, J. [AES, Medford, NY 11763 (United States)

2010-11-04

280

High performance N204/amine elements: Blowapart. [test, and analysis of single element injectors  

NASA Technical Reports Server (NTRS)

The work is reported which was conducted to define the mechanisms governing blowapart of hypergolic propellant through the design, fabrication, test, and analysis of single element injectors. Data were developed that show the parameters exhibiting a controlling influence over blowapart are the chamber pressure, orifice diameter, and propellant temperature. Mixing, popping (cyclic blowapart), low pressure separation, and high pressure separation were identified as modes of reactive impingement.

Lawver, B. R.

1974-01-01

281

Single-Pass Flow Through (SPFT) Testing of Fluidized-Bed Steam Reforming (FBSR) Waste Forms  

Microsoft Academic Search

Two samples of fluidized-bed steam reforming (FBSR) mineral waste form product were subjected to single-pass flow-through (SPFT) testing. Sample LAW 1123 resulted from pilot-scale FBSR processing with a Hanford Envelope A low-activity waste (LAW) simulant. Sample SBW 1173 resulted from pilot-scale FBSR processing with an Idaho National Laboratory (INL) simulant commonly referred to as sodium-bearing waste (SBW). The pilot-scale waste

T. H. Lorier; J. M. Pareizs; C. M. Jantzen

2005-01-01

282

The development and testing of a heat pump for heating a single room  

Microsoft Academic Search

The development and testing of a heat pump designed to provide heat only to a single room of a dwelling are discussed. The through-the-wall unit is an air-to-air heat pump based on standard refrigeration components, with various noise-reduction, control and heat exchanger components added. Measurements of heat output, the extraction of heat from a cold chamber, electric power consumption, air

P. Freund; R. K. Cattell

1980-01-01

283

Proton Single Event Effects (SEE) Testing of the Myrinet Crossbar Switch and Network Interface Card  

NASA Technical Reports Server (NTRS)

As part of the Remote Exploration and Experimentation Project (REE), work was performed to do a proton SEE (Single Event Effect) evaluation of the Myricom network protocol system (Myrinet). This testing included the evaluation of the Myrinet crossbar switch and the Network Interface Card (NIC). To this end, two crossbar switch devices and five components in the NIC were exposed to the proton beam at the University of California at Davis Crocker Nuclear Laboratory (CNL).

Howard, James W., Jr.; LaBel, Kenneth A.; Carts, Martin A.; Stattel, Ronald; Irwin, Timothy L.; Day, John H. (Technical Monitor)

2002-01-01

284

Single-cell thermionic fuel element design and testing for space power systems  

SciTech Connect

The use of electric heaters in the single-cell thermionic fuel elements(TFE) of the Topaz-II power systems provides the ability to gain actual operating parameters of the power source prior to loading nuclear fuel. This feature can provide satellite payload designers with the output parameters of the power source that would be used for space operations. This design also allows personnel to work on the system after operation without the concerns associated with radioactive material produced from nuclear tests. The results of electrically testing a complete system provide a high level of confidence that the device will perform as expected in orbit.

Wold, S.K. [Sandia National Labs., Albuquerque, NM (United States)

1994-12-31

285

Fabrication and Testing of Full-Length Single-Cell Externally Fueled Converters for Thermionic Reactors  

SciTech Connect

The preceding paper described designs and analyses of thermionic reactors employing full-core-length single-cell converters with their heated emitters located on the outside of their internally cooled collectors, and it presented results of detailed parametric analyses which illustrate the benefits of this unconventional design. The present paper describes the fabrication and testing of full-length prototypical converters, both unfueled and fueled, and presents parametric results of electrically heated tests. The unfueled converter tests demonstrated the practicality of operating such long converters without shorting across a 0.3-mm interelectrode gap. They produced a measured peak output of 751 watts(e) from a single diode and a peak efficiency of 15.4%. The fueled converter tests measured the parametric performance of prototypic UO(subscript 2)-fueled converters designed for subsequent in-pile testing. They employed revolver-shaped tungsten elements with a central emitter hole surrounded by six fuel chambers. The full-length converters were heated by a water-cooled RF-induction coil inside an ion-pumped vacuum chamber. This required development of high-vacuum coaxial RF feedthroughs. In-pile test rules required multiple containment of the UO (subscript 2)-fuel, which complicated the fabrication of the test article and required successful development of techniques for welding tungsten and other refractory components. The test measured a peak power output of 530 watts(e) or 7.1 watts/cm (superscript 2) at an efficiency of 11.5%. There are three copies in the file. Cross-Reference a copy FSC-ESD-217-94-529 in the ESD files with a CID #8574.

Schock, Alfred

1994-06-01

286

IIST and BETHSY Counterpart Tests on a PWR Total Loss-of-Feedwater Transient with Two Different Bleed-and-Feed Scenarios  

SciTech Connect

The thermal-hydraulic phenomena and recovery actions of loss-of-feedwater (LOFW) incidents in a pressurized water reactor were investigated experimentally at the Institute of Nuclear Energy Research Integral System Test (IIST) facility. To understand whether the physical phenomena observed in the full-height and full-pressure facility during an LOFW transient can be simulated in the reduced-height and reduced-pressure IIST facility, two counterpart tests based on the same scenarios as those of the BETHSY tests were performed. These two tests performed in BETHSY differ mainly at the initiation of the bleed-and-feed process on the primary side in order to examine the effectiveness of recovery measures on the processes of the pressurizer power-operated relief valves early and late opening. The initial and boundary conditions of the current tests were determined by scaling down the corresponding conditions of the LOFW experiments performed at BETHSY. In view of the inherent differences in design, scaling approach, and facility operation conditions in the systems, the consistency between the counterpart tests is examined by identifying key thermal-hydraulic phenomena and clarifying their differences. The results of the IIST and BETHSY tests showed the common thermal-hydraulic behaviors of key parameters, such as system pressure, void fraction in the hot leg, primary coolant inventory, pressurizer level, and discharged mass evolutions. The chronological events studied in the IIST facility are generally consistent with those studied in BETHSY. The results from the IIST facility may not be exact replications of the BETHSY response; however, the physics involved in bleed-and-feed are well measured and modeled.

Liu, T.-J

2002-01-15

287

Classifying performance impairment in response to sleep loss using pattern recognition algorithms on single session testing  

PubMed Central

There is currently no “gold standard” marker of cognitive performance impairment resulting from sleep loss. We utilized pattern recognition algorithms to determine which features of data collected under controlled laboratory conditions could most reliably identify cognitive performance impairment in response to sleep loss using data from only one testing session, such as would occur in the “real world” or field conditions. A training set for testing the pattern recognition algorithms was developed using objective Psychomotor Vigilance Task (PVT) and subjective Karolinska Sleepiness Scale (KSS) data collected from laboratory studies during which subjects were sleep deprived for 26 – 52 hours. The algorithm was then tested in data from both laboratory and field experiments. The pattern recognition algorithm was able to identify performance impairment with a single testing session in individuals studied under laboratory conditions using PVT, KSS, length of time awake and time of day information with sensitivity and specificity as high as 82%. When this algorithm was tested on data collected under real-world conditions from individuals whose data were not in the training set, accuracy of predictions for individuals categorized with low performance impairment were as high as 98%. Predictions for medium and severe performance impairment were less accurate. We conclude that pattern recognition algorithms may be a promising method for identifying performance impairment in individuals using only current information about the individual’s behavior. Single testing features (e.g., number of PVT lapses) with high correlation with performance impairment in the laboratory setting may not be the best indicators of performance impairment under real-world conditions. Pattern recognition algorithms should be further tested for their ability to be used in conjunction with other assessments of sleepiness in real-world conditions to quantify performance impairment in response to sleep loss. PMID:22959616

St. Hilaire, Melissa A.; Sullivan, Jason P.; Anderson, Clare; Cohen, Daniel A.; Barger, Laura K.; Lockley, Steven W.; Klerman, Elizabeth B.

2012-01-01

288

Dynamic testing of a single-degree-of-freedom strapdown gyroscope  

NASA Technical Reports Server (NTRS)

Test methods and results are presented for the equivalent average input rate of a single-degree-of-freedom gyroscope operated both open loop and with a ternary-logic pulse-torque-to-balance loop during multiaxis angular oscillation. For the open-loop tests, good agreement was obtained with theoretical results. Two-axis testing was performed for oscillations about the Input-Output axes, the Input-Spin axes, and the Spin-Output axes. These tests run in the torque-to-balance mode revealed significant departures from open-loop results in the induced drift rate. An analysis is developed explaining much of the closed-loop data presented. Test data for the gryoscope in a ternary torque-to-balance loop with constant input rates is presented. The tests demonstrate that the instrument rate linearity does not change with interrogation frequency from 3,600 to 14,400 Hz if the torque coil is tuned to offer a resistive load to the current switch. Analysis cited shows that gyroscope lag compensation eliminates multiple pulsing and other equivalent forms of degraded resolution in a wide variety of quantizing loops. This result is test verified for the ternary delta-modulator loop.

Lory, C. B.; Feldman, J.; Sinkiewicz, J. S., Jr.

1971-01-01

289

Modified single lap joint (MSLJ) test configuration for the determination of adhesive fracture energy  

NASA Astrophysics Data System (ADS)

In this work, a modification has been proposed to the traditional single lap joint (SLJ) configuration, to overcome the wide scatter in the fracture toughness measurement due to adhesive fillets. This modification, referred to as the Modified Single Lap Joint (MSLJ), is made by implanting end pre-cracks in the adhesive layer at the center of the bond line in a conventional SLJ. This ensured that during testing, the crack propagated from both ends of the overlap and reduced the effect of spew fillets. MSLJ joints made from unidirectional fibre composite substrates (913C - HTA 12K 5-34%) and either of two types of (Redux 322 and Redux 335K) film adhesive were tested to measure the adhesive fracture energy, Gac. The values of Gac measured were compared with those from similar tests conducted on SLJ and double cantilever beam (DCB) configurations. It was observed that the scatter in the fracture energy measurements obtained from the MSLJ specimens were reduced by more than 30% in comparison with those from the SLJ specimens. The values of adhesive fracture energy from the MSLJ and DCB test geometries were in good agreement. These results are especially useful in the critical design of structural components for aerospace and defense applications as a typical design engineer can use the value of Gac to design for how long an adhesively bonded joint will last when subjected to stresses in friendly or hostile environments.

Kumar, S. B.; Sridhar, I.; Sivashanker, S.; Bag, Asim; Osiyemi, S. O.

2005-04-01

290

In Situ Characterization of a Single Fracture Hydromechanical Behavior from Hydraulic Pulse Tests coupled to Simultaneous Pressure Normal  

E-print Network

In Situ Characterization of a Single Fracture Hydromechanical Behavior from Hydraulic Pulse Tests of the other surrounding fractures of the network. 1 INTRODUCTION Hydraulic pulse injection testing in single borehole has previously been applied to determine hydraulic properties of rock fractures, including

Vallée, Martin

291

Infrastructure Development of Single Cell Testing Capability at A0 Facility  

SciTech Connect

The objective of this technical note is to document the details of the infrastructure development process that was realized at the A0 photo injector facility to establish RF cold testing capability for 1.3 GHz superconducting niobium single cell cavities. The activity began the last quarter of CY 2006 and ended the first quarter of CY 2009. The whole process involved addressing various aspects such as design of vertical insert and lifting fixture, modification of existing RF test station and design of new couplers, development of a Temperature Mapping (T-Map) system, radiation considerations for the test location (north cave), update of existing High Pressure Rinse (HPR) system, preparation of necessary safety documents and eventually obtaining an Operational Readiness Clearance (ORC). Figure 1 illustrates the various components of the development process. In the past, the north cave test station at A0 has supported the cold testing 3.9 GHz nine cell and single cell cavities, thus some of the components were available for use and some needed modification. The test dewar had the capacity to accommodate 1.3 GHz single cells although a new vertical insert that could handle both cavity types (1.3 and 3.9 GHz) had to be designed. The existing cryogenic system with an average capacity of {approx} 0.5 g/sec was deemed sufficient. The RF system was updated with broadband components and an additional amplifier with higher power capacity to handle higher gradients usually achieved in 1.3 GHz cavities. The initial testing phase was arbitrated to proceed with fixed power coupling. A new temperature mapping system was developed to provide the diagnostic tool for hot spot studies, quench characterization and field emission studies. The defining feature of this system was the use of diode sensors instead of the traditional carbon resistors as sensing elements. The unidirectional current carrying capacity (forward bias) of the diodes provided for the ease of multiplexing of the system, thus substantially reducing the number of cables required to power the sensors. The high gradient capacity of the 1.3 GHz cavities required a revision of the radiation shielding and interlocks. The cave was updated as per the recommendations of the radiation safety committee. The high pressure rinse system was updated with new adapters to assist the rinsing 1.3 GHz single cell cavities. Finally, a proposal for cold testing 1.3 GHz single cell cavities at A0 north cave was made to the small experiments approval committee, radiation safety committee and the Tevatron cryogenic safety sub-committee for an operational readiness clearance and the same was approved. The project was classified under research and development of single cell cavities (project 18) and was allocated a budget of $200,000 in FY 2007.

Dhanaraj, Nandhini; Padilla, R.; Reid, J.; Khabiboulline, T.; Ge, M.; Mukherjee, A.; Rakhnov, I.; Ginsburg, C.; Wu, G.; Harms, E.; Carter, H.; /Fermilab

2009-09-01

292

Robotic Searching for Stationary, Unknown and Transient Radio Sources  

E-print Network

of the transient target localization problem such as Single Robot Single Target (SRST), Multiple Robots Single Target (MRST), Single Robot Multiple Targets (SRMT) and Multiple Robots Multiple Targets (MRMT). We propose the expected searching time (EST) as a primary...

Kim, Chang Young

2012-07-16

293

Are single-well "push-pull" tests suitable tracer methods for aquifer characterization?  

NASA Astrophysics Data System (ADS)

Recently, investigations were conducted for geological and hydrogeological characterisation of the sedimentary coastal basin of Horonobe (Hokkaido, Japan). Coastal areas are typical geological settings in Japan, which are less tectonically active than the mountain ranges. In Asia, and especially in Japan, these areas are often densely populated. Therefore, it is important to investigate the behaviour of solutes in such unconsolidated aquifers. In such settings sometimes only single boreholes or groundwater monitoring wells are available for aquifer testing for various reasons, e.g. depths of more than 100 m below ground level and slow groundwater velocities due to density driven flow. A standard tracer test with several involved groundwater monitoring wells is generally very difficult or even not possible at these depths. One of the most important questions in our project was how we can obtain information about chemical and hydraulic properties in such aquifers. Is it possible to characterize solute transport behaviour parameters with only one available groundwater monitoring well or borehole? A so-called "push-pull" test may be one suitable method for aquifer testing with only one available access point. In a push-pull test a known amount of several solutes including a conservative tracer is injected into the aquifer ("push") and afterwards extracted ("pull"). The measured breakthrough curve during the pumping back phase can then be analysed. This method has already been used previously with various aims, also in the recent project (e.g. Hebig et al. 2011, Zeilfelder et al. 2012). However, different test setups produced different tracer breakthrough curves. As no systematic evaluation of this aquifer tracer test method was done so far, nothing is known about its repeatability. Does the injection and extraction rate influence the shape of the breakthrough curve? Which role plays the often applied "chaser", which is used to push the test solution out from the borehole and gravel pack? How does density difference between the original groundwater and the test solution influence the tracer breakthrough curves? To solve these questions, seven push-pull tests were performed under controlled boundary conditions in the same well DD-2 (100 m depth). Only single parameters, as e.g. flow rate or salinization of the test solution, were varied during the experiments. By conducting these different test setups, conclusions could be drawn about the application of the push-pull method under different settings. References: Hebig, K.H., Ito, N., Scheytt, T.J. & Marui, A. (2011). Hydraulic and hydrochemical characterization of deep coastal sedimentary basins by single-well Push-Pull tests. GSA Annual Meeting, 9-12 October 2011, Minneapolis, USA. Zeilfelder, S., Ito, N., Marui, A., Hebig, K. & Scheytt, T. (2012). Push-Pull-Test und Tracer-Test in ei-nem tiefen Grundwasserleiter in Kameoka, Japan. Kurzfassung in: Liedl, R., Burghardt, D., Simon, E., Reimann, T. & Kaufmann-Knoke (Hg.). Grundwasserschutz und Grundwassernutzung. Tagung der Fachsektion Hydrogeologie in der DGG (FH-DGG). 16. - 20. Mai 2012, Dresden. Kurfassungen der Vorträge und Poster. Schriftenreihe der DGG, Heft 78, S. 192.

Hebig, Klaus; Zeilfelder, Sarah; Ito, Narimitsu; Machida, Isao; Scheytt, Traugott; Marui, Atsunao

2013-04-01

294

Single gimbal/strapdown inertial navigation system for use on spin stabilized flight test vehicles  

SciTech Connect

A hybrid strapdown inertial navigation system intended for use on spin stabilized flight test vehicles is described. The configuration of the navigator which is briefly described consists of three floated rate integrating gyros, one of which is used in conjunction with the gimbal with the remaining two operated in a rate gyro mode. Outputs from the two strapdown gyros and three accelerometers are digitized and processed by a high performance computer. The navigation algorithms utilize a direction cosine matrix formulation for the attitude computation implemented in the digital computer. The implementation of this algorithm for the single gimbal configuration is described. An accuracy model and results for a reentry vehicle flight test trajectory are presented. The flight test performance from launch to reentry is presented.

Watts, A.C.; Andreas, R.D.

1980-01-01

295

Testing for Suspected Impairments and Dissociations in Single-Case Studies in Neuropsychology: Evaluation of Alternatives Using Monte Carlo  

E-print Network

very high for zD. A new method of testing for a difference (the revised standardized difference testTesting for Suspected Impairments and Dissociations in Single-Case Studies in Neuropsychology: Evaluation of Alternatives Using Monte Carlo Simulations and Revised Tests for Dissociations John R. Crawford

Crawford, John R.

296

Single Rod Heat Transfer Tests to Study the Effects of Crud Deposition  

SciTech Connect

Researchers have performed many studies to try to understand crud formation on the fuel pin clad surfaces, which has been observed in pressurized water reactors (PWR) as a result of sub-cooled nucleate boiling and precipitation reactions. Crud deposits, may cause an unexpected change in core power distribution known as crud induced power shift (CIPS) or axial offset anomaly (AOA) if boron species accumulate in the deposits. If the crud deposit is thick enough, the potential exists for fuel rod surface dryout. The Westinghouse Advanced Loop Tester (WALT) at the George Westinghouse Science and Technology Center (STC) will be utilized to examine the effects of crud formation on fuel pin clad dryout. This paper describes a single heated rod test facility designed and fabricated by Westinghouse to study the effects of crud deposition at PWR reactor operating conditions. This test loop is a single rod facility with or without grid support structures on the heater rod and can be used for forced convection and sub-cooled boiling tests with and without crud deposition. Sub-cooled boiling experiments at PWR reactor operating conditions are currently being performed at this facility. The single electrical heated rod in this test facility is instrumented with four movable thermocouples to measure the inside wall temperatures at four azimuthal locations within the rod. In addition, there are two fixed thermocouples to measure the inlet and outlet temperatures of the water flowing on the outside of the heated rod such that an overall energy balance (i.e. comparing the heat absorbed by the water coolant to the measured rod electrical power) can be performed on the facility. This paper will present forced convection and boiling heat transfer curves for clean rod surfaces. Comparison with forced convection correlations and sub-cooled boiling correlations are also presented in this paper. (authors)

Wang, G.; Byers, W.A.; Karoutas, Z.E.; Young, M.Y.; Jacko, R.J. [Westinghouse Electric Company LLC. (United States); Hochreiter, L.E. [The Pennsylvania State University, 302 Walker Building, University Park, PA 16802 (United States)

2006-07-01

297

Fluid Structure Interaction in a Cold Flow Test and Transient CFD Analysis of Out-of-Round Nozzles  

NASA Technical Reports Server (NTRS)

This viewgraph presentation describes two nozzle fluid flow interactions. They include: 1) Cold flow nozzle tests with fluid-structure interaction at nozzle separated flow; and 2) CFD analysis for nozzle flow and side loads of nozzle extensions with various out-of-round cases.

Ruf, Joseph; Brown, Andrew; McDaniels, David; Wang, Ten-See

2010-01-01

298

Single-neuron axonal pathfinding under geometric guidance: low-dose-methylmercury developmental neurotoxicity test.  

PubMed

Because the nervous system is most vulnerable to toxicants during development, there is a crucial need for a highly sensitive developmental-neurotoxicity-test model to detect potential toxicants at low doses. We developed a lab-on-chip wherein single-neuron axonal pathfinding under geometric guidance was created using soft lithography and laser cell-micropatterning techniques. After coating the surface with L1, an axon-specific member of the Ig family of cell adhesion molecules (CAMs), and optimizing microunit geometric parameters, we introduced low-dose methylmercury, a well-known, environmentally significant neurotoxicant, in the shared medium. Its developmental neurotoxicity was evaluated using a novel axonal pathfinding assay including axonal turning and branching rates at turning points in this model. Compared to the conventional neurite-outgrowth assay, this model's detection threshold for low-dose methylmercury was 10-fold more sensitive at comparable exposure durations. These preliminary results support study of developmental effects of known and potential neurotoxicants on axon pathfinding. This novel assay model would be useful to study neuronal disease mechanisms at the single-cell level. To our knowledge, the potential of methylmercury chloride to cause acute in vitro developmental neurotoxicity (DNT) at such a low dosage has not been reported. This is the first DNT test model with high reproducibility to use single-neuron axonal pathfinding under precise geometric guidance. PMID:25041816

Wei, Lina; Sweeney, Andrew J; Sheng, Liyuan; Fang, Yu; Kindy, Mark S; Xi, Tingfei; Gao, Bruce Z

2014-09-21

299

The Single Intradermal Cervical Comparative Test Interferes with Johne’s Disease ELISA Diagnostics  

PubMed Central

Enzyme-linked immunosorbent assays (ELISA) of milk and serum samples are a routinely used method of screening herds for Mycobacterium avium subspecies paratuberculosis (MAP). Infection with MAP causes granulomatous enteritis of ruminants known as Johne’s disease (JD). The sensitivity (Se) and specificity (Sp) of MAP ELISAs leads to difficulties in the identification of both infected and infectious animals. Interference with MAP ELISA Se and Sp has been reported in MAP seronegative cows following administration of purified protein derivative (PPD) as part of intradermal testing for bovine tuberculosis (bTB). The aim of this study is to examine the impact of the single intradermal cervical comparative test (SICCT) for bTB, on both serum and milk MAP ELISA tests, in a herd containing both seropositive and seronegative cows pre-SICCT. A secondary objective is to provide appropriate timing of JD ELISA tests in relation to the SICCT. A herd of 139 cows were serum and milk sampled pre- and post-SICCT administration. Prior to SICCT, 6% of the herd tested seropositive for MAP using milk ELISA, with 8% positive on serum. ID Screen Paratuberculosis Indirect Screening Test (ID Vet) was used to screen the herd. Within 14?days of PPD administration, a significant increase in the prevalence of seropositive cows was recorded. Identical prevalence’s were recorded with both test matrices (39%). ELISA values remained significantly higher until day 43 post-SICCT in milk (P?=?0.850), and day 71 in serum (P?=?0.602). If the “new” positives detected post-bTB testing are deemed false positives due to generation of cross-reacting antibodies by administration of PPD, milk would appear a more suitable sample for JD ELISA testing within 2?months of SICCT. In summary, sampling for JD utilizing milk ELISA should be avoided in the 43-day period following PPD administration, with serum ELISA sampling avoided for an additional 28?days.

Kennedy, Aideen E.; Da Silva, Ana T.; Byrne, Noel; Govender, Rodney; MacSharry, John; O’Mahony, Jim; Sayers, Riona G.

2014-01-01

300

Resampling-based methods in single and multiple testing for equality of covariance/correlation matrices.  

PubMed

Traditional resampling-based tests for homogeneity in covariance matrices across multiple groups resample residuals, that is, data centered by group means. These residuals do not share the same second moments when the null hypothesis is false, which makes them difficult to use in the setting of multiple testing. An alternative approach is to resample standardized residuals, data centered by group sample means and standardized by group sample covariance matrices. This approach, however, has been observed to inflate type I error when sample size is small or data are generated from heavy-tailed distributions. We propose to improve this approach by using robust estimation for the first and second moments. We discuss two statistics: the Bartlett statistic and a statistic based on eigen-decomposition of sample covariance matrices. Both statistics can be expressed in terms of standardized errors under the null hypothesis. These methods are extended to test homogeneity in correlation matrices. Using simulation studies, we demonstrate that the robust resampling approach provides comparable or superior performance, relative to traditional approaches, for single testing and reasonable performance for multiple testing. The proposed methods are applied to data collected in an HIV vaccine trial to investigate possible determinants, including vaccine status, vaccine-induced immune response level and viral genotype, of unusual correlation pattern between HIV viral load and CD4 count in newly infected patients. PMID:22740584

Yang, Yang; DeGruttola, Victor

2012-01-01

301

RELAP5/MOD3 Analysis of Transient Steam-Generator Behavior During Turbine Trip Test of a Prototype Fast Breeder Reactor MONJU  

SciTech Connect

In order to develop a thermal-hydraulic model of the steam-generator (SG) to simulate transient phenomena in the sodium cooled fast breeder reactor (FBR) MONJU, Japan Nuclear Energy Safety Organization (JNES) verified the SG model using the RELAP5/MOD3 code against the results of the turbine trip test at a 40% power load of MONJU. The modeling by using RELAP5 was considered to explain the significant observed behaviors of the pressure and the temperature of the EV steam outlet, and the temperature of water supply distributing piping till 600 seconds after the turbine trip. The analysis results of these behaviors showed good agreement with the test results based on results of parameter study as the blow efficiency (release coef.) and heat transferred from the helical coil region to the down-comer (temperature heating down-comer tubes). It was found that the RELAP5/MOD3 code with a two-fluids model can predict well the physical situation: the gas-phase of steam generated by the decompression boiling moves upward in the down-comer tubes accompanied by the enthalpy increase of the water supply chambers; and that the pressure change of a 'shoulder' like shape is induced by the mass balance between the steam mass generated in the down-comer tubes and the steam mass blown from the SG. The applicability of RELAP5/MOD3 to SG modeling was confirmed by simulating the actual FBR system. (authors)

Yoshihisa Shindo; Hiroshi Endo; Tomoko Ishizu; Kazuo Haga [Japan Nuclear Energy Safety Organization (Japan)

2006-07-01

302

Gravitational independence of single-breath washout tests in recumbent dogs  

NASA Technical Reports Server (NTRS)

The effect of gravitational orientation in the mechanism of lung filling and emptying in dogs was examined by conducting simultaneously Ar-bolus and N2 single-breath washout tests (SBWTs) in 10 anesthetized dogs (prone and supine), with three of the dogs subjected to body rotation. Transpulmonary pressure was measured simultaneously, allowing identification of the lung volume above residual volume at which there was an inflection point in the pressure-volume curve. Combined resident gas and bolus SBWTs in recumbent dogs were found to be different from such tests in humans; in dogs, the regional distribution of ventilation was not primarily determined by gravity. The measurements did not make it possible to discern exact mechanisms of filling and emptying, but both processes appear to be related to lung, thorax, and mediastinum interactions and/or differences in regional mechanical properties of the lungs.

Tomioka, Shinichi; Kubo, Susumu; Guy, Harold J. B.; Prisk, G. K.

1988-01-01

303

Loop Identification and Capacity Estimation of Digital Subscriber Lines with Single Ended Line Testing  

NASA Astrophysics Data System (ADS)

Digital subscriber lines offer the possibility to deliver broadband services over the existing telephone network. Still, beforehand subscriber loops must be tested to see whether they can support high-speed data services, and at what bit rate. From the existing measurement techniques, Single Ended Line Testing is often preferred because all necessary measurements can be performed from the central office. Consequently the capacity cannot be measured directly, but should be calculated through the estimation of the loop make-up. This paper discusses some main difficulties of this identification. Moreover, in contrast to the traditional approach where the data are interpreted in the time domain, this paper presents a new approach by doing most of the processing in the frequency domain.

Neus, Carine; Foubert, Wim; van Biesen, Leo

304

Mathematical Model for Solute Transport in a Single Borehole Dipole Flow Tracer Test  

NASA Astrophysics Data System (ADS)

The basic design of a single-borehole dipole-flow tracer test involves a well with an injection and an extraction chamber separated by some vertical distance and isolated from one another both using an inflatable packer. The test utilizes a small pump to create a vertical dipole-flow field. After the flow field is stabilized and the pumping rate and drawdowns in these chambers are recorded, a tracer mass is introduced instantaneously into injection chamber and the concentration breakthrough curve is monitored in the extraction chamber. The horizontal hydraulic conductivity, the vertical hydraulic conductivity and longitudinal dispersivity can be determined by using an appropriate mathematical model to analyze the breakthrough curves and drawdowns in these chambers. Existing mathematical models based on streamtube approach are only effective for interpreting tracer tests under advective-dominated condition. Furthermore, these solutions are appropriate for generation of breakthrough curve in the extraction chamber only because the transverse dispersion term is neglected. This study presents a novel mathematical model for describing solute transport in a single-borehole dipole-flow tracer test. In developing the mathematical model, a steady-state analytical solution for drawdown distribution is first obtained and the radial and vertical components of pore velocity are determined. Subsequently, the two-dimensional advection-dispersion equation in cylindrical coordinates for describing tracer transport in a dipole-flow field is derived based on the second order dispersion tensor theory. The Laplace transformed finite difference technique is applied to solve the two-dimensional advection-dispersion equation in cylindrical coordinates with variable- dependent coefficients. The developed model has an advantage over the existing models because it can be valid under a wide range of longitudianl dispersivity. The novel mathematical model is applied to simulate the concentration contour in the aquifer and the breakthrough curves in the chambers. Moreover, a curve-fitting method is proposed to determine the longitudinal dispersivity.

Chen, J.; Chan, Y.; Liang, C.

2007-12-01

305

A Comparison of Three IRT Approaches to Examinee Ability Change Modeling in a Single-Group Anchor Test Design  

ERIC Educational Resources Information Center

Typically a longitudinal growth modeling based on item response theory (IRT) requires repeated measures data from a single group with the same test design. If operational or item exposure problems are present, the same test may not be employed to collect data for longitudinal analyses and tests at multiple time points are constructed with unique…

Paek, Insu; Park, Hyun-Jeong; Cai, Li; Chi, Eunlim

2014-01-01

306

Thermal effects on single-well chemical-tracer tests for measuring residual oil saturation  

SciTech Connect

This paper reports on the single-well chemical-tracer (SWCT) test for measuring residual oil saturation, S{sub or}, which often involves injecting cool fluid containing a reactive tracer into a warm formation. The S{sub or} estimation with this method depends on the separation between reactant and product tracers. Because the reaction rate is temperature-dependent, accounting for the thermal effects may be necessary to obtain reliable results. Two simulator models are normally used to interpret SWCT tests. The ideal model is used for relatively homogeneous sandstone formations. The pore-diffusion model is used for heterogeneous carbonate formations. Both models have now been solved with appropriate heat-balance equations. THese nonisothermal models have been used to reinterpret several previously reported field tests. For the worst case, the estimated S{sub or} value from the nonisothermal model is 5% PV higher than that from the isothermal model. Inequality conditions have been developed that divide the parameter space of SWCT tests into two regions, depending on the location isothermal and nonisothermal models are essentially equal. The inequality conditions have been extended to include the effects of over and underburden layers and intervening shales in layered systems.

Park, Y.J. (Pusan National Inst. of Technology (KR)); Deans, H.A. (Wyoming Univ., Laramie, WY (United States)); Tezduyar, T.E. (Houston Univ., Clear Lake, TX (United States))

1991-09-01

307

Transient detector apparatus  

Microsoft Academic Search

A transient detector apparatus utilizing peak and slope detectors to determine the presence of transient signal in a logic signal. Individual slope measurements of the input signal are compared with a logic criteria to establish the occurrence of a transient. The peak voltage and pulse width of a transient are digitized in order to time tag or isolate a transient

Lapeyrolerie

1985-01-01

308

Evaluation of the Non-Transient Hydrologic Source Term from the CAMBRIC Underground Nuclear Test in Frenchman Flat, Nevada Test Site  

Microsoft Academic Search

Hydrologic Source Term (HST) calculations completed in 1998 at the CAMBRIC underground nuclear test site were LLNL's first attempt to simulate a hydrologic source term at the NTS by linking groundwater flow and transport modeling with geochemical modeling (Tompson et al., 1999). Significant effort was applied to develop a framework that modeled in detail the flow regime and captured all

A B Tompson; R M Maxwell; S F Carle; M Zavarin; G A Pawloski; D E Shumaker

2005-01-01

309

A numerical comparison with an exact solution for the transient response of a cylinder immersed in a fluid. [computer simulated underwater tests to determine transient response of a submerged cylindrical shell  

NASA Technical Reports Server (NTRS)

The transient response of an elastic cylindrical shell immersed in an acoustic media that is engulfed by a plane wave is determined numerically. The method applies to the USA-STAGS code which utilizes the finite element method for the structural analysis and the doubly asymptotic approximation for the fluid-structure interaction. The calculations are compared to an exact analysis for two separate loading cases: a plane step wave and an exponentially decaying plane wave.

Giltrud, M. E.; Lucas, D. S.

1979-01-01

310

Compendium of Single-Event Latchup and Total Ionizing Dose Test Results of Commercial Analog to Digital Converters  

NASA Technical Reports Server (NTRS)

This paper reports single-event latchup and total dose results for a variety of analog to digital converters targeted for possible use in NASA spacecraft's. The compendium covers devices tested over the last 15 years.

Irom, Farokh; Agarwal, Shri G.

2012-01-01

311

A Transient Numerical Simulation of Perched Ground-Water Flow at the Test Reactor Area, Idaho National Engineering and Environmental Laboratory, Idaho, 1952-94  

SciTech Connect

Studies of flow through the unsaturated zone and perched ground-water zones above the Snake River Plain aquifer are part of the overall assessment of ground-water flow and determination of the fate and transport of contaminants in the subsurface at the Idaho National Engineering and Environmental Laboratory (INEEL). These studies include definition of the hydrologic controls on the formation of perched ground-water zones and description of the transport and fate of wastewater constituents as they moved through the unsaturated zone. The definition of hydrologic controls requires stratigraphic correlation of basalt flows and sedimentary interbeds within the saturated zone, analysis of hydraulic properties of unsaturated-zone rocks, numerical modeling of the formation of perched ground-water zones, and batch and column experiments to determine rock-water geochemical processes. This report describes the development of a transient numerical simulation that was used to evaluate a conceptual model of flow through perched ground-water zones beneath wastewater infiltration ponds at the Test Reactor Area (TRA).

B. R. Orr (USGS)

1999-11-01

312

Preliminary Test Results from 650 MHz Single Cell Medium Beta Cavities for Project X  

SciTech Connect

We have fabricated two single cell 650 MHz {beta}=0.61 cavities of a JLab design, which possibly can be used for the proposed Project X proton linac application. Both cavities were manufactured at JLab from RRR>250 niobium sheet of 4 mm thickness using standard techniques such as deep drawing, electron beam welding, buffered chemical polishing, hydrogen degassing heat treatment, high pressure ultrapure water rinsing and clean room assembly. Initially cavity no. 1 was -- after final surface treatment by buffered chemical polishing (BCP) -- measured without any provisions for stiffening. As expected, the pressure sensitivity and the Lorentz Force detuning coefficients were relatively high; however, the RF performance was very encouraging: the cavity exhibited a Q-value > 10{sup 11} at 1.6K, corresponding to a residual resistance of < 1.5 n{Omega} The initial gradient was limited to E{sub acc} ~ 18 MV/m, limited by field emission. In a subsequent test, the cavity was re-rinsed and stiffened up, resulting in a somewhat improved mechanical behavior, but no improvement in rf performance. The second cavity was also tested twice, before and after low temperature baking. The results from all tests are reported in this contribution.

Marhauser, Frank; Kneisel, Peter; Burrill, Andrew; Kushnick, Peter; Rimmer, R. A.

2011-07-01

313

A Comparison of Single-Cycle Versus Multiple-Cycle Proof Testing Strategies  

NASA Technical Reports Server (NTRS)

Single-cycle and multiple-cycle proof testing (SCPT and MCPT) strategies for reusable aerospace propulsion system components are critically evaluated and compared from a rigorous elastic-plastic fracture mechanics perspective. Earlier MCPT studies are briefly reviewed. New J-integral estimation methods for semielliptical surface cracks and cracks at notches are derived and validated. Engineering methods are developed to characterize crack growth rates during elastic-plastic fatigue crack growth (FCG) and the tear-fatigue interaction near instability. Surface crack growth experiments are conducted with Inconel 718 to characterize tearing resistance, FCG under small-scale yielding and elastic-plastic conditions, and crack growth during simulated MCPT. Fractography and acoustic emission studies provide additional insight. The relative merits of SCPT and MCPT are directly compared using a probabilistic analysis linked with an elastic-plastic crack growth computer code. The conditional probability of failure in service is computed for a population of components that have survived a previous proof test, based on an assumed distribution of initial crack depths. Parameter studies investigate the influence of proof factor, tearing resistance, crack shape, initial crack depth distribution, and notches on the MCPT versus SCPT comparison. The parameter studies provide a rational basis to formulate conclusions about the relative advantages and disadvantages of SCPT and MCPT. Practical engineering guidelines are proposed to help select the optimum proof test protocol in a given application.

McClung, R. C.; Chell, G. G.; Millwater, H. R.; Russell, D. A.; Millwater, H. R.

1999-01-01

314

Prototype powerline transient source and direction of propagation detector  

Microsoft Academic Search

Random impulse voltage transients that occur on electrical power distribution systems can cause physical damage to critical loads, resulting in operational failure. There are numerous transient detection devices, but until recently no device could determine the direction of propagation of transients on a powerline. This report is an evaluation of two prototype transient-direction detectors. Tests revealed they provide a simple

M. N. Smith; K. T. Huang

1975-01-01

315

Numerical simulation of selective laser sintering transient temperature field  

Microsoft Academic Search

A numerical simulation pattern based on finite element algorithm is proposed for calculation of selective laser sintering transient temperature field. The patter is based on the transient thermal radiation and the boundary conditions is concerned soundly, particularly during the transient sintering the relation between thermal conductivity and transient sintering temperature is set up on the basis of practical test to

Jian Xing; Xiaogang Sun

2009-01-01

316

An Experimental Proposal to Test Dynamic Quantum Non-locality with Single-Atom Interferometry  

E-print Network

Quantum non-locality based on the well-known Bell inequality is of kinematic nature. A different type of quantum non-locality, the non-locality of the quantum equation of motion, is recently put forward with connection to the Aharonov-Bohm effect [Nature Phys. 6, 151 (2010)]. Evolution of the displacement operator provides an example to manifest such dynamic quantum non-locality. We propose an experiment using single-atom interferometry to test such dynamic quantum non-locality. We show how to measure evolution of the displacement operator with clod atoms in a spin-dependent optical lattice potential and discuss signature to identify dynamic quantum non-locality under a realistic experimental setting.

Zhu, Shi-Liang; Zhang, Dan-Wei; Duan, Lu-Ming

2010-01-01

317

An experimental proposal to test dynamic quantum non-locality with single-atom interferometry  

NASA Astrophysics Data System (ADS)

Quantum non-locality based on the well-known Bell inequality is of kinematic nature. A different type of quantum non-locality, the non-locality of the quantum equation of motion, is recently put forward with connection to the Aharonov-Bohm effect (Popescu S., Nat. Phys., 6 (2010) 151). Evolution of the displacement operator provides an example to manifest such dynamic quantum non-locality. We propose an experiment using single-atom interferometry to test such dynamic quantum non-locality. We show how to measure evolution of the displacement operator with cold atoms in a spin-dependent optical lattice potential and discuss signature to identify dynamic quantum non-locality under a realistic experimental setting.

Zhu, Shi-Liang; Xue, Zheng-Yuan; Zhang, Dan-Wei; Duan, Lu-Ming

2011-06-01

318

Analysis and testing of high entrainment single nozzle jet pumps with variable mixing tubes  

NASA Technical Reports Server (NTRS)

An analytical model was developed to predict the performance characteristics of axisymmetric single-nozzle jet pumps with variable area mixing tubes. The primary flow may be subsonic or supersonic. The computer program uses integral techniques to calculate the velocity profiles and the wall static pressures that result from the mixing of the supersonic primary jet and the subsonic secondary flow. An experimental program was conducted to measure mixing tube wall static pressure variations, velocity profiles, and temperature profiles in a variable area mixing tube with a supersonic primary jet. Static pressure variations were measured at four different secondary flow rates. These test results were used to evaluate the analytical model. The analytical results compared well to the experimental data. Therefore, the analysis is believed to be ready for use to relate jet pump performance characteristics to mixing tube design.

Hickman, K. E.; Hill, P. G.; Gilbert, G. B.

1972-01-01

319

Single and multiple impact ignition of new and aged high explosives in the Steven Impact Test  

SciTech Connect

Threshold impact velocities for ignition of exothermic reaction were determined for several new and aged HMX-based solid high explosives using three types of projectiles in the Steven Test. Multiple impact threshold velocities were found to be approximately 10% lower in damaged charges that did not react in one or more prior impacts. Projectiles with protrusions that concentrate the friction work in a small volume of explosive reduced the threshold velocities by approximately 30%. Flat projectiles required nearly twice as high velocities for ignition as rounded projectiles. Blast overpressure gauges were used for both pristine and damaged charges to quantitatively measure reaction violence. Reactive flow calculations of single and multiple impacts with various projectiles suggest that the ignition rates double in damaged charges.

Chidester, S K; DePiero, A H; Garza, R G; Tarver, C M

1999-06-01

320

A high speed transient recorder  

Microsoft Academic Search

The paper describes how the design of a high-speed oscillograph may be modified to produce a near-linear recordable sweep of 10-8 sec duration. The techniques necessary to reproduce photographically single transients of this order are discussed.

D R Hardy

1952-01-01

321

Test of a single module of the J-PET scanner based on plastic scintillators  

E-print Network

Time of Flight Positron Emission Tomography scanner based on plastic scintillators is being developed at the Jagiellonian University by the J-PET collaboration. The main challenge of the conducted research lies in the elaboration of a method allowing application of plastic scintillators for the detection of low energy gamma quanta. In this article we report on tests of a single detection module built out from BC-420 plastic scintillator strip (with dimensions of 5x19x300mm^3) read out at two ends by Hamamatsu R5320 photomultipliers. The measurements were performed using collimated beam of annihilation quanta from the 68Ge isotope and applying the Serial Data Analyzer (Lecroy SDA6000A) which enabled sampling of signals with 50ps intervals. The time resolution of the prototype module was established to be better than 80ps (sigma) for a single level discrimination. The spatial resolution of the determination of the hit position along the strip was determined to be about 0.93cm (sigma) for the annihilation quanta...

Moskal, P; Bednarski, T; Czerwi?ski, E; Kap?on, ?; Kubicz, E; Moskal, I; Pawlik-Nied?wiecka, M; Sharma, N G; Silarski, M; Zieli?ski, M; Zo?, N; Bia?as, P; Gajos, A; Kochanowski, A; Korcyl, G; Kowal, J; Kowalski, P; Kozik, T; Krzemie?, W; Molenda, M; Pa?ka, M; Raczy?ski, L; Rudy, Z; Salabura, P; S?omski, A; Smyrski, J; Strzelecki, A; Wieczorek, A; Wi?licki, W

2014-01-01

322

Test of a single module of the J-PET scanner based on plastic scintillators  

E-print Network

Time of Flight Positron Emission Tomography scanner based on plastic scintillators is being developed at the Jagiellonian University by the J-PET collaboration. The main challenge of the conducted research lies in the elaboration of a method allowing application of plastic scintillators for the detection of low energy gamma quanta. In this article we report on tests of a single detection module built out from BC-420 plastic scintillator strip (with dimensions of 5x19x300mm^3) read out at two ends by Hamamatsu R5320 photomultipliers. The measurements were performed using collimated beam of annihilation quanta from the 68Ge isotope and applying the Serial Data Analyzer (Lecroy SDA6000A) which enabled sampling of signals with 50ps intervals. The time resolution of the prototype module was established to be better than 80ps (sigma) for a single level discrimination. The spatial resolution of the determination of the hit position along the strip was determined to be about 0.93cm (sigma) for the annihilation quanta. The fractional energy resolution for the energy E deposited by the annihilation quanta via the Compton scattering amounts to sigma(E)/E = 0.044/sqrt(E[MeV]) and corresponds to the sigma(E)/E of 7.5% at the Compton edge.

P. Moskal; Sz. Nied?wiecki; T. Bednarski; E. Czerwi?ski; ?. Kap?on; E. Kubicz; I. Moskal; M. Pawlik-Nied?wiecka; N. G. Sharma; M. Silarski; M. Zieli?ski; N. Zo?; P. Bia?as; A. Gajos; A. Kochanowski; G. Korcyl; J. Kowal; P. Kowalski; T. Kozik; W. Krzemie?; M. Molenda; M. Pa?ka; L. Raczy?ski; Z. Rudy; P. Salabura; A. S?omski; J. Smyrski; A. Strzelecki; A. Wieczorek; W. Wi?licki

2014-07-28

323

Test of a single module of the J-PET scanner based on plastic scintillators  

NASA Astrophysics Data System (ADS)

A Time of Flight Positron Emission Tomography scanner based on plastic scintillators is being developed at the Jagiellonian University by the J-PET collaboration. The main challenge of the conducted research lies in the elaboration of a method allowing application of plastic scintillators for the detection of low energy gamma quanta. In this paper we report on tests of a single detection module built out from the BC-420 plastic scintillator strip (with dimensions of 5×19×300 mm3) read out at two ends by Hamamatsu R5320 photomultipliers. The measurements were performed using collimated beam of annihilation quanta from the 68Ge isotope and applying the Serial Data Analyzer (Lecroy SDA6000A) which enabled sampling of signals with 50 ps intervals. The time resolution of the prototype module was established to be better than 80 ps (?) for a single level discrimination. The spatial resolution of the determination of the hit position along the strip was determined to be about 0.93 cm (?) for the annihilation quanta. The fractional energy resolution for the energy E deposited by the annihilation quanta via the Compton scattering amounts to ?(E)/E?0.044/?{E(MeV)} and corresponds to the ?(E)/E of 7.5% at the Compton edge.

Moskal, P.; Nied?wiecki, Sz.; Bednarski, T.; Czerwi?ski, E.; Kap?on, ?.; Kubicz, E.; Moskal, I.; Pawlik-Nied?wiecka, M.; Sharma, N. G.; Silarski, M.; Zieli?ski, M.; Zo?, N.; Bia?as, P.; Gajos, A.; Kochanowski, A.; Korcyl, G.; Kowal, J.; Kowalski, P.; Kozik, T.; Krzemie?, W.; Molenda, M.; Pa?ka, M.; Raczy?ski, L.; Rudy, Z.; Salabura, P.; S?omski, A.; Smyrski, J.; Strzelecki, A.; Wieczorek, A.; Wi?licki, W.

2014-11-01

324

Crop and Substrate Tests with Single Use Rooting "Pillows" for the VEGGIE Plant Growth Hardware  

NASA Technical Reports Server (NTRS)

VEGGIE is a small plant production chamber built by ORBITEC. This chamber can be collapsed for easy stowage and deployed in orbit. It is designed for gravity independent operation, and provides 0.17 square m of crop growth area with three primary subsystems: an LED light panel, extendable transparent Teflon bellows to enclose the plants, and a wicking reservoir. VEGGIE would provide the capability for astronauts to grow fresh foods for dietary supplementation. Initial planting concepts tested with the VEGGIE included direct seeding or plug placement on the reservoir surface. These options had issues of salt accumulation and eventual toxicity if the reservoir was filled with nutrient solution, and hardware reuse was limited due to sanitation. In response a rooting packet or "pillow" concept was developed: single-use bags of media containing time release fertilizer with a wicking surface contacting the VEGGIE reservoir. Pillows being tested are small electrostatic bags with a Nitex nylon mesh side, each holding 100 mL of dry media. Six pillows fit in one VEGGIE unit; however pillow size could vary depending on crop selected. Seeds can be planted directly in pillows and planted pillows can be hydrated in space as desired. Our goals were to define optimal media and crops for an ISS mission scenario. Plant tests in pillows were performed in a controlled environment chamber set to habitat-relevant conditions, and capillary reservoir analogs were utilized. Media tested within pillows included: a commercial peat-based potting mix, arcillite (calcined clay), perlite: vermiculite, and peat-based: arcillite blends. Testing included 15 types of leafy greens, snow pea, radish, and herbs. Media performance was crop dependent, but generally plants showed the greatest growth in the peat-based: arcillite mixes. Crops with the best performance in pillows were identified, and testing is underway with select leafy greens examining plant and microbial load response to repeated harvest. We plan to use findings from previous flight testing with media to evaluate the effects of capillary flow from the reservoir to pillows in microgravity.

Massa, Gioia; Newsham, Gerard; Caro, Janicce; Stutte, Gary; Morrow, Robert; Wheeler, Raymond

2011-01-01

325

Modeling Single Well Injection-Withdrawal (SWIW) Tests for Characterization of Complex Fracture-Matrix Systems  

NASA Astrophysics Data System (ADS)

An essential condition for performance evaluation of enhanced geothermal systems (EGS) resides in the ability to reliably predict fluid flow and heat transport in fractured porous rocks, where fast convection-dispersive transport through the fracture network can be strongly affected by heat conduction into the adjacent rock matrix. SWIW tests are single-well tracer tests that involve an initial period of fluid and tracer injection followed by a period of fluid withdrawal. As a result of the flow field reversal, the measured breakthrough curves tend to be less sensitive to advective heterogeneities and more sensitive to matrix diffusion and sorption, making this method very valuable in characterizing fracture-matrix interaction and evaluating matrix properties. In particular, we propose using SWIW tests before and after hydrofracking operations, to help assess the means by which hydrofracking increases permeability and enhances fracture-matrix interaction. In the present study, we have modeled single-well injection-withdrawal (SWIW) tests for non-sorbing and sorbing tracers, using the mixed Eulerian-Lagrangian transport simulator TRIPOLY, which solves tracer advection and dispersion in fracture networks together with solute exchange processes between the fractures and the porous matrix. Our simulations were conducted for hypothetical but workable SWIW test designs considering a variety of statistically generated 2D fracture-matrix systems. Parameter sensitivity studies were completed on three physical parameters of the rock matrix, namely porosity, diffusion coefficient and retardation coefficient, in order to investigate their impact on the fracture-matrix solute exchange process. Hydraulic fracturing, or hydrofracking, was modeled in two different ways, one by increasing the fracture aperture for flow and the other one by adding a new set of fractures to the fracture network. The results of all these different tests were analyzed by studying the population of matrix blocks, the tracer spatial distribution, and the breakthrough curves (BTCs), while performing mass balance checks to ensure numerical accuracy. The possibility of inferring from SWIW-test BTCs relevant information on the physical parameters of the fracture-matrix system was investigated. Our results clearly demonstrate the importance of matrix effects in the solute transport process. The sensitivity studies illustrate the increased importance of the matrix as providing a retardation mechanism as matrix porosity, diffusion coefficient, or retardation coefficient increase. Heat convection and conduction can be shown to be mathematically equivalent to advection, diffusion, and sorption of tracer, making these tracer studies directly useful for analysis of EGS. Interestingly, preliminary results before and after hydrofracking are insensitive to adding more fractures while somewhat sensitive to aperture increase, making SWIW tests a possible means of discriminating between these two potential hydrofracking effects. However, our base case fracture network is highly connected, potentially minimizing the effect of hydrofracking. Further study is needed using a sparser network to study hydrofracking under more realistic conditions.

Cotte, F.; Doughty, C.; Birkholzer, J. T.

2010-12-01

326

Value of a Single-Tube Widal Test in Diagnosis of Typhoid Fever in Vietnam  

PubMed Central

The diagnostic value of an acute-phase single-tube Widal test for suspected typhoid fever was evaluated with 2,000 Vietnamese patients admitted to an infectious disease referral hospital between 1993 and 1998. Test patients had suspected typhoid fever and a blood culture positive for Salmonella typhi (n= 1,400) or Salmonella paratyphi A (n = 45). Control patients had a febrile illness for which another cause was confirmed (malaria [n = 103], dengue [n = 76], or bacteremia due to another microorganism [n = 156] or tetanus (n = 265). An O-agglutinin titer of ?100 was found in 18% of the febrile controls and 7% of the tetanus patients. Corresponding values for H agglutinins were 8 and 1%, respectively. The O-agglutinin titer was ?100 in 83% of the blood culture-positive typhoid fever cases, and the H-agglutinin titer was ?100 in 67%. The disease prevalence in investigated patients in this hospital was 30.8% (95% confidence interval, 26.8 to 35.1%); at this prevalence, an elevated level of H agglutinins gave better positive predictive values for typhoid fever than did O agglutinins. With a cutoff titer of ?200 for O agglutinin or ?100 for H agglutinin, the Widal test would diagnose correctly 74% of the blood culture-positive cases of typhoid fever. However, 14% of the positive results would be false-positive, and 10% of the negative results would be false-negative. The Widal test can be helpful in the laboratory diagnosis of typhoid fever in Vietnam if interpreted with care. PMID:10449469

Parry, Christopher M.; Hoa, Nguyen Thi Tuyet; Diep, To Song; Wain, John; Chinh, Nguyen Tran; Vinh, Ha; Hien, Tran Tinh; White, Nicholas J.; Farrar, Jeremy J.

1999-01-01

327

Transient Receptor Potential Channel Polymorphisms Are Associated with the Somatosensory Function in Neuropathic Pain Patients  

Microsoft Academic Search

Transient receptor potential channels are important mediators of thermal and mechanical stimuli and play an important role in neuropathic pain. The contribution of hereditary variants in the genes of transient receptor potential channels to neuropathic pain is unknown. We investigated the frequency of transient receptor potential ankyrin 1, transient receptor potential melastin 8 and transient receptor potential vanilloid 1 single

Andreas Binder; Denisa May; Ralf Baron; Christoph Maier; Thomas R. Tölle; Rolf-Detlef Treede; Achim Berthele; Frank Faltraco; Herta Flor; Janne Gierthmühlen; Sierk Haenisch; Volker Huge; Walter Magerl; Christian Maihöfner; Helmut Richter; Roman Rolke; Andrea Scherens; Nurcan Üçeyler; Mike Ufer; Gunnar Wasner; Jihong Zhu; Ingolf Cascorbi; Carlo Gaetano

2011-01-01

328

Atomic transient recorder.  

PubMed

In Bohr's model of the hydrogen atom, the electron takes about 150 attoseconds (1 as = 10(-18) s) to orbit around the proton, defining the characteristic timescale for dynamics in the electronic shell of atoms. Recording atomic transients in real time requires excitation and probing on this scale. The recent observation of single sub-femtosecond (1 fs = 10(-15) s) extreme ultraviolet (XUV) light pulses has stimulated the extension of techniques of femtochemistry into the attosecond regime. Here we demonstrate the generation and measurement of single 250-attosecond XUV pulses. We use these pulses to excite atoms, which in turn emit electrons. An intense, waveform-controlled, few cycle laser pulse obtains 'tomographic images' of the time-momentum distribution of the ejected electrons. Tomographic images of primary (photo)electrons yield accurate information of the duration and frequency sweep of the excitation pulse, whereas the same measurements on secondary (Auger) electrons will provide insight into the relaxation dynamics of the electronic shell following excitation. With the current approximately 750-nm laser probe and approximately 100-eV excitation, our transient recorder is capable of resolving atomic electron dynamics within the Bohr orbit time. PMID:14985755

Kienberger, R; Goulielmakis, E; Uiberacker, M; Baltuska, A; Yakovlev, V; Bammer, F; Scrinzi, A; Westerwalbesloh, Th; Kleineberg, U; Heinzmann, U; Drescher, M; Krausz, F

2004-02-26

329

Single Event Effects Test Results for Advanced Field Programmable Gate Arrays  

NASA Technical Reports Server (NTRS)

Reconfigurable Field Programmable Gate Arrays (FPGAs) from Altera and Actel and an FPGA-based quick-turnApplication Specific Integrated Circuit (ASIC) from Altera were subjected to single-event testing using heavy ions. Both Altera devices (Stratix II and HardCopy II) exhibited a low latchup threshold (below an LET of 3 MeV-cm2/mg) and thus are not recommended for applications in the space radiation environment. The flash-based Actel ProASIC Plus device did not exhibit latchup to an effective LET of 75 MeV-cm2/mg at room temperature. In addition, these tests did not show flash cell charge loss (upset) or retention damage. Upset characterization of the design-level flip-flops yielded an LET threshold below 10 MeV-cm2/mg and a high LET cross section of about lxlO-6 cm2/bit for storing ones and about lxl0-7 cm2/bit for storing zeros . Thus, the ProASIC device may be suitable for critical flight applications with appropriate triple modular redundancy mitigation techniques.

Allen, Gregory R.; Swift, Gary M.

2006-01-01

330

Ground Vibration and Flight Flutter Tests of the Single-Seat F-16XL Aircraft with a Modified Wing.  

National Technical Information Service (NTIS)

The NASA single-seat F-16XL aircraft was modified by the addition of a glove to the left wing. Vibration tests were conducted on the ground to assess the changes to the aircraft caused by the glove. Flight Luther testing was conducted on the aircraft with...

D. F. Voracek

1993-01-01

331

Setting Passing Scores on Passage-Based Tests: A Comparison of Traditional and Single-Passage Bookmark Methods  

ERIC Educational Resources Information Center

In this study, a variation of the bookmark standard setting procedure for passage-based tests is proposed in which separate ordered item booklets are created for the items associated with each passage. This variation is compared to the traditional bookmark procedure for a fifth-grade reading test. The results showed that the single-passage…

Skaggs, Gary; Hein, Serge F.; Awuor, Risper

2007-01-01

332

Combined array CGH plus SNP genome analyses in a single assay for optimized clinical testing  

PubMed Central

In clinical diagnostics, both array comparative genomic hybridization (array CGH) and single nucleotide polymorphism (SNP) genotyping have proven to be powerful genomic technologies utilized for the evaluation of developmental delay, multiple congenital anomalies, and neuropsychiatric disorders. Differences in the ability to resolve genomic changes between these arrays may constitute an implementation challenge for clinicians: which platform (SNP vs array CGH) might best detect the underlying genetic cause for the disease in the patient? While only SNP arrays enable the detection of copy number neutral regions of absence of heterozygosity (AOH), they have limited ability to detect single-exon copy number variants (CNVs) due to the distribution of SNPs across the genome. To provide comprehensive clinical testing for both CNVs and copy-neutral AOH, we enhanced our custom-designed high-resolution oligonucleotide array that has exon-targeted coverage of 1860 genes with 60?000 SNP probes, referred to as Chromosomal Microarray Analysis – Comprehensive (CMA-COMP). Of the 3240 cases evaluated by this array, clinically significant CNVs were detected in 445 cases including 21 cases with exonic events. In addition, 162 cases (5.0%) showed at least one AOH region >10?Mb. We demonstrate that even though this array has a lower density of SNP probes than other commercially available SNP arrays, it reliably detected AOH events >10?Mb as well as exonic CNVs beyond the detection limitations of SNP genotyping. Thus, combining SNP probes and exon-targeted array CGH into one platform provides clinically useful genetic screening in an efficient manner. PMID:23695279

Wiszniewska, Joanna; Bi, Weimin; Shaw, Chad; Stankiewicz, Pawel; Kang, Sung-Hae L; Pursley, Amber N; Lalani, Seema; Hixson, Patricia; Gambin, Tomasz; Tsai, Chun-hui; Bock, Hans-Georg; Descartes, Maria; Probst, Frank J; Scaglia, Fernando; Beaudet, Arthur L; Lupski, James R; Eng, Christine; Wai Cheung, Sau; Bacino, Carlos; Patel, Ankita

2014-01-01

333

Single molecule bridge as a testing ground for using NGF outside of the steady current regime  

NASA Astrophysics Data System (ADS)

The simplest nanoscopic system, a molecular bridge consisting of a molecular island with one or few electronic or vibronic levels coupled to non-interacting leads can be treated using non-equilibrium Green's functions (NGF). We follow the well known procedure of Jauho, Wingreen and Meir (JWM). In the present work, we concentrate on the little investigated transient behavior of the molecular bridge undergoing abrupt changes. The transient process depends on the initial conditions at a finite time which may incorporate initial correlations. As an example, we study the electron response to sudden connecting the molecule to one or both leads. To obtain explicit solutions, we neglect all interactions at the island, whose role is mimicked by the island-leads coupling. We explore this analogy and obtain a complete solution for the transient NGF for arbitrary “initial correlations” represented by off-diagonal coherences between the initial electron state of the island and of the leads. This direct one-electron solution is confronted with the field theoretic approach in the particular case of the switch-on states, for which the initial correlations result from the previous history of the system. This is formally captured by the partitioning-in-time of the NGF, which we combine with the JWM theory. It is the virtue of partitioning method to express the transient NGF in terms of the building blocks of stationary-state NGF with zero, one or both leads connected. The direct and the partitioning solutions are reduced explicitly from one to the other, clarifying thus the meaning of the singular terms of the self-energy for correlated initial conditions.

Velický, B.; Kalvová, A.; Špi?ka, V.

2010-01-01

334

Biaxial constitutive modelling and testing of a single crystal superalloy at elevated temperatures  

NASA Technical Reports Server (NTRS)

A viscoplastic constitutive model for single crystal superalloys is developed from crystallographic slip theory. The model is applied to the tension and torsion deformation behavior of the single crystal superalloy PWA 1480 at 871 C (1600 F). Both octahedral and cube slip behavior are needed to model the deformation behavior of single crystal superalloys at elevated temperature.

Walker, K. P.; Jordan, E. M.

1989-01-01

335

Study on a test of optical stochastic cooling scheme in a single pass beam line  

SciTech Connect

A feasibility study of an experiment to test the principle of optical stochastic cooling is presented. We propose to build a new beamline in the extraction area of the ALS Booster synchrotron, where we will include a bypass lattice similar to the lattice that could be used in the cooling insertion in a storage ring. Of course, in the single pass beamline we cannot achieve cooling, but we can test all the functions of the bypass lattice that are required to achieve cooling in a storage ring. As it is stated in, there are stringent requirements on the time-of-flight properties of the bypass lattice employed in a cooling scheme. The pathlengths of particle trajectories in the bypass must be fairly insensitive to the standard set of errors that usually affect the performance of storage rings. Namely, it is necessary to preserve all fluctuations in the longitudinal particle density within the beam from the beginning to the end of the bypass lattice with the accuracy of {lambda}/2{pi}, where A is the carrying (optical) wavelength. According to, cooling will completely vanish if a combined effect of all kinds of errors will produce a spread of the pathlengths of particle trajectories larger than {lambda}/2 and the cooling time will almost double if the spread of the pathlengths is {lambda}/2{pi}. At a first glance, {lambda}/2{pi} {approx_equal} 0.1/{mu}m is such a small value that satisfying this accuracy looks nearly impossible. However, simulations show that a carefully designed bypass can meet all the requirements even with rather conservative tolerance to errors.

Chattopadhyay, S.; Kim, C.; Massoletti, D.; Zholents, A. [and others

1997-01-01

336

Chlamydia trachomatis test-of-cure cannot be based on a single highly sensitive laboratory test taken at least 3 weeks after treatment.  

PubMed

Current test-of-cure practice in patients with Chlamydia trachomatis (Ct) infection is to confirm cure with a single test taken at least 3 weeks after treatment. Effectiveness of single-time-point testing however lacks a scientific evidence basis and the high sensitivity of laboratory assays nowadays in use for this purpose may compromise the clinical significance of their results. Prospectively following 59 treated Ct infections, administering care as usual, the presence of Ct plasmid DNA and rRNA was systematically assessed by multiple time-sequential measurements, i.e. on 18 samples taken per patient during 8 weeks following treatment with a single dose of 1000 mg Azythromycin. A high proportion (42%) of Ct infections tested positive on at least one of the samples taken after 3 weeks. Patients' test results showed substantial inter-individual and intra-individual variation over time and by type of NAAT used. We demonstrated frequent intermittent positive patterns in Ct test results over time, and strongly argue against current test-of-cure practice. PMID:22470526

Dukers-Muijrers, Nicole H T M; Morré, Servaas A; Speksnijder, Arjen; van der Sande, Marianne A B; Hoebe, Christian J P A

2012-01-01

337

Initial comparison of single cylinder Stirling engine computer model predictions with test results  

NASA Technical Reports Server (NTRS)

A NASA developed digital computer code for a Stirling engine, modelling the performance of a single cylinder rhombic drive ground performance unit (GPU), is presented and its predictions are compared to test results. The GPU engine incorporates eight regenerator/cooler units and the engine working space is modelled by thirteen control volumes. The model calculates indicated power and efficiency for a given engine speed, mean pressure, heater and expansion space metal temperatures and cooler water inlet temperature and flow rate. Comparison of predicted and observed powers implies that the reference pressure drop calculations underestimate actual pressure drop, possibly due to oil contamination in the regenerator/cooler units, methane contamination in the working gas or the underestimation of mechanical loss. For a working gas of hydrogen, the predicted values of brake power are from 0 to 6% higher than experimental values, and brake efficiency is 6 to 16% higher, while for helium the predicted brake power and efficiency are 2 to 15% higher than the experimental.

Tew, R. C., Jr.; Thieme, L. G.; Miao, D.

1979-01-01

338

Coaxial HOM Coupler designs tested on a single cell niobium cavity  

SciTech Connect

Coaxial higher order mode (HOM) couplers have been developed for HERA cavities and are used in TESLA, SNS and JLab upgrade cavities. The principle of operation is the rejection of the fundamental mode by the tunable filter of the coupler and the transmission of the HOMs. It has been recognized recently that inappropriate thermal designs of the feedthrough for the pick-up probe of the HOM coupler will not sufficiently carry away the heat generated in the probe tip by the fundamental mode fields, causing a built-up of the heating of the niobium probe tip and subsequently, a deterioration of the cavity quality factor has been observed in CW operation. An improvement of the situation has been realized by a better thermal design of the feedthrough incorporating a sapphire rf window [1]. An alternative is a modification of the coupler loop (?F? ? part) with an extension towards the pick-up probe. This design has been tested on a single cell niobium cavity in comparison to a ''standard TESLA'' configuration by measuring the Eacc behavior at 2 K. The measurements clearly indicate that the modified version of the coupler loop is thermally much more stable than the standard version.

Peter Kneisel; Genfa Wu; Gianluigi Ciovati; Jacek Sekutowicz

2006-08-28

339

On The Way To Off-equatorial Charged Discs Near Compact Objects - Single Test Particles Approximation  

NASA Astrophysics Data System (ADS)

We present our recent studies of charged particles motion out of the equatorial plane in strong gravitational and electromagnetic fields. Within the general relativistic approach, we have demonstrated that the interplay between gravitational and electromagnetic action may allow for stable off-equatorial circular motion along the so-called halo orbits near compact objects, such as rotating magnetic compact stars and Kerr black holes immersed in an asymptotically uniform magnetic field of external origin. Locations of halo orbits correspond to minima of the two-dimensional effective potential, which exhibits several qualitativelly different kinds of behaviour, reflecting the charge of moving particles and orientation of the motion. Along with the study of the halo motion itself, we have discussed the general motion in the related off-equatorial potential lobes, demonstrating its chaoticness or regularity in terms of the Poincaré surfaces of sections and recurrence plots. A possible outlook of this study is to build a single test particles model of putative circumpulsar discs consisting of charged dust particles. Institute of Physics and Astronomical Institute have been operated under the projects MSM 4781305903 and AV 0Z10030501, and further supported by the Centre for Theoretical Astrophysics LC06014 in the Czech Republic. JK, VK and ZS thank the Czech Science Foundation (ref. P209/10/P190, 205/07/0052, 202/09/0772). OK acknowledges the doctoral student program of the Czech Science Foundation (205/09/H033).

Kovar, Jiri; Kopacek, O.; Karas, V.; Stuchlik, Z.

2010-02-01

340

Tracer Tests in a Fractured Dolomite: 2. Controls on Mass-Recovery Rates for a Single-Porosity, Heterogeneous Conceptualization  

SciTech Connect

A single-well injection-withdrawal (SWIW) test is evaluated as a tool to differentiate between single- and double-porosity conceptualizations of a system. Results from single-porosity simulations incorporating plume drift are also compared to observed data from a recent series of SWIW tests conducted in a fractured dolomite unit, for which a double-porosity conceptualization has been proposed. We evaluate the difficulty of differentiating the response for a double-porosity conceptualization from that for a heterogeneous, single-porosity conceptualization incorporating plume drift. Results of sensitivity studies on multiple, stochastically generated, heterogeneous transmissivity fields indicate that to simulate extremely slow mass-recovery rates for a SWIW test with a single-porosity conceptualization, the following conditions must be present: plume drift, extreme heterogeneities (high {sigma}InT), and an unusual configuration of the high and low transmissivity regions relative to the well location. A compilation of existing data suggests that the high degree of heterogeneity necessary is rare at the SWIW test scale.The observed data from the SWIW tracer tests cannot be matched to numerical simulation results when a single-porosity conceptualization is assumed. A signature of significant drift is less than 100% mass recovery with a zero derivative with respect to time of the late-time normalized cumulative mass curve indicating mass transported outside the capture zone of the withdrawal well. To minimize the risk of misinterpretation, an important design feature for SWIW tests is the collection of late-time data so that percent total mass recovery can be calculated.

Altman, S.J.; Meigs, L.C.; Jones, T.L.

1999-03-04

341

Single-Event Effects Ground Testing and On-Orbit Rate Prediction Methods: The Past, Present and Future  

NASA Technical Reports Server (NTRS)

Over the past 27 years, or so, increased concern over single event effects in spacecraft systems has resulted in research, development and engineering activities centered around a better understanding of the space radiation environment, single event effects predictive methods, ground test protocols, and test facility developments. This research has led to fairly well developed methods for assessing the impact of the space radiation environment on systems that contain SEE sensitive devices and the development of mitigation strategies either at the system or device level.

Reed, Robert A.; Kinnison, Jim; Pickel, Jim; Buchner, Stephen; Marshall, Paul W.; Kniffin, Scott; LaBel, Kenneth A.

2003-01-01

342

Adequacy of Power-to-Mass Scaling in Simulating PWR Incident Transient for Reduced-Height, Reduced-Pressure and Full-Height, Full-Pressure Integral System Test Facilities  

SciTech Connect

A complete scheme of scaling methods to design the reduced-height, reduced-pressure (RHRP) Institute of Nuclear Energy Research Integral System Test (IIST) facility and to specify test conditions for incident simulation was developed. In order to preserve core decay power history and coolant mass inventory during a transient, a unique power-to-mass scaling method is proposed and utilized for RHRP and full-height, full-pressure (FHFP) systems. To validate the current scaling method, three counterpart tests done at the IIST facility are compared with the FHFP tests in small-break loss-of-coolant, station blackout, and loss-of-feedwater accidents performed at the Large-Scale Test Facility (LSTF) and the BETHSY test facility. Although differences appeared in design, scaling, and operation conditions among the IIST, LSTF, and BETHSY test facilities, the important physical phenomena shown in the facilities are almost the same. The physics involved in incident transient phenomena are well measured and modeled by showing the common thermal-hydraulic behavior of key parameters and the general consistency of chronological events. The results also confirm the adequacy of power-to-mass scaling methodology.

Liu, T.-J.; Lee, C.-H

2004-03-15

343

Racial/ethnic and gender differences among older adults in nonmonogamous partnerships, time spent single, and HIV testing  

PubMed Central

Background A higher frequency of nonmonogamy, due in part to lower marriage prevalence, may contribute to elevated HIV/STD rates among older Blacks. Methods To examine race and gender differences in nonmonogamy, time spent single (i.e., not married or cohabiting), and HIV testing in older adults, we analyzed U.S. population-based data from the 2005-06 National Social Life, Health, and Aging Project (NSHAP) for 2,825 heterosexual participants ages 57-85 years. Results Blacks spent greater portions of their adult lives single than did Hispanics or Whites and were far more likely to report recent nonmonogamous partnerships (23.4% vs. 10.0% and 8.2%). Among individuals reporting sex in the prior 5 years, nonmonogamous partnerships were strongly associated with time spent single during the period. Control for time spent single and other covariates reduced the association of Black race with nonmonogamous partnerships for men but increased it for women. Less than 20% reported ever testing for HIV; less than 6% had been recommended testing by a provider. Testing rates, highest in Black men and White women, differed little by history of nonmonogamous partnerships within gender strata. Conclusions Singlehood helps to explain higher nonmonogamous partnership rates in older Black men but not older Black women. Older adults rarely receive or are recommended HIV testing, a key strategy for reducing heterosexual HIV transmission. PMID:22082721

Harawa, Nina T.; Leng, Mei; Kim, Junyeop; Cunningham, William Emery

2011-01-01

344

Workshop on Radio Transients  

NASA Astrophysics Data System (ADS)

abstract-type="normal">SummaryWe are entering a new era in the study of variable and transient radio sources. This workshop discussed the instruments and the strategies employed to study those sources, how they are identified and classified, how results from different surveys can be compared, and how radio observations tie in with those at other wavelengths. The emphasis was on learning what common ground there is between the plethora of on-going projects, how methods and code can be shared, and how best practices regarding survey strategy could be adopted. The workshop featured the four topics below. Each topic commenced with a fairly brief introductory talk, which then developed into discussion. By way of preparation, participants had been invited to upload and discuss one slide per topic to a wiki ahead of the workshop. 1. Telescopes, instrumentation and survey strategy. New radio facilities and on-going projects (including upgrades) are both studying the variability of the radio sky, and searching for transients. The discussion first centred on the status of those facilities, and on projects with a time-domain focus, both ongoing and planned, before turning to factors driving choices of instrumentation, such as phased array versus single pixel feeds, the field of view, spatial and time resolution, frequency and bandwidth, depth, area, and cadence of the surveys. 2. Detection, pipelines, and classification. The workshop debated (a) the factors that influence decisions to study variability in the (u,v) plane, in images, or in catalogues, (b) whether, and how much, pipeline code could potentially be shared between one project and another, and which software packages are best for different approaches, (c) how data are stored and later accessed, and (d) how transients and variables are defined and classified. 3. Statistics, interpretation, and synthesis. It then discussed how (i) the choice of facility and strategy and (ii) detection and classification schemes influence what is seen (in terms of types of object and rates) by different surveys, (iii) how results from different surveys could be compared, and (iv) how what we know from existing surveys drives choices (i) and (ii), particularly as regards finding new classes of object. 4. Multiwavelength approaches. The workshop concluded by discussing what information is needed from wavelengths other than radio in order to classify transients and variables adequately and predict their rates as a function of topics (1), (2) and (3). It asked what the constraints are on responding to, and issuing triggers for, follow-up observations, and how that might feed back into considerations for designing our telescopes and surveys.

Croft, Steve; Gaensler, Bryan

2012-04-01

345

Single and reciprocal friction testing of micropatterned surfaces for orthopedic device design.  

PubMed

The use of micropatterning to create uniform surface morphologies has been cited as yielding improvements in the coefficient of friction during high velocity sliding contact. Studies have not been preformed to determine if these micropatterns could also be useful in biomedical applications, such as total joint replacement surfaces, where the lower sliding velocities are used. In addition, other factors such as lubricant viscosities and materials used are more tightly constrained. In this study, the effect of pattern geometry, feature size and lubricant on contact friction and surface damage was investigated using 316L steel in sliding contact with a stainless steel and polyethylene pins. Using a novel proprietary forming process that creates millions of microstructures in parallel, a variety of micropatterned surfaces were fabricated to study the influence of shape (oval, circular, square), geometry (depressions, pillars) and feature size (10, 50 and 100 mm) on both contact friction and surface damage. All samples were 316L stainless steel and the static and dynamic coefficients of friction when in contact with either a stainless steel or polyethylene counterface were measured in dry and lubricated conditions. All samples were characterized for surface uniformity and pattern aspect ratio using white light interferometry and optical microscope image analysis, and the coefficients of friction were measured for each surface/lubricant/pin system using a CETR scratch testing system. Results showed that round depressions with diameters of 10 ?m had a significantly lower steady state coefficient of friction than the non-patterned substrates or substrates with greater diameter depression patterns. In addition, our results showed that the single-pass coefficient of friction measurements were not good predictors of the steady state coefficient of friction values measured. PMID:22340690

Mitchell, N; Eljach, C; Lodge, B; Sharp, J L; Desjardins, J D; Kennedy, M S

2012-03-01

346

A Field-Tested Task Analysis for Creating Single-Subject Graphs Using Microsoft[R] Office Excel  

ERIC Educational Resources Information Center

Creating single-subject (SS) graphs is challenging for many researchers and practitioners because it is a complex task with many steps. Although several authors have introduced guidelines for creating SS graphs, many users continue to experience frustration. The purpose of this article is to minimize these frustrations by providing a field-tested

Lo, Ya-yu; Konrad, Moira

2007-01-01

347

Wind Uplift Behavior of Mechanically Attached Single-Ply Roofing Systems: The Need for Correction Factors in Standardized Tests  

Microsoft Academic Search

In the United States, currently there are three consensus test methods for determining the wind uplift capacity of mechanically- attached single-ply roofing membrane systems. Each is based upon a specific specimen size and static loading regime. However, few studies have examined the relationship, if any, of failure loads among these methods. This study was conducted to determine the effects of

David O. Prevatt; Scott D. Schiff; Joshua S. Stamm; Amolprasad S. Kulkarni

2008-01-01

348

Testing a Poisson Counter Model for Visual Identification of Briefly Presented, Mutually Confusable Single Stimuli in Pure Accuracy Tasks  

ERIC Educational Resources Information Center

The authors propose and test a simple model of the time course of visual identification of briefly presented, mutually confusable single stimuli in pure accuracy tasks. The model implies that during stimulus analysis, tentative categorizations that stimulus i belongs to category j are made at a constant Poisson rate, v(i, j). The analysis is…

Kyllingsbaek, Soren; Markussen, Bo; Bundesen, Claus

2012-01-01

349

The verification test of thermal distortion decoupling design for single panel of space micro-strip array antenna  

Microsoft Academic Search

This paper studied the structural characters of space micro-strip array antenna. It is analyzed how the thermal stress between the panel and the metal feed line (TEM line) at the back greatly affects the distortion of single panel. To verifying the effectiveness of decoupling design for thermal distortion, a verification test in low temperature and in vacuum is designed with

Wei Juan-fang; Song Yan-Ping; Fan Nai-Kang; Wang Bo-Sheng

2006-01-01

350

Radiation effect characterization and test methods of single-chip and multi-chip stacked 16Mbit DRAMs  

SciTech Connect

This paper presents radiation effects characterization performed by the NASA Goddard Space Flight Center (GSFC) on spaceflight candidate 16Mbit DRAMs. This includes heavy ion, proton, and Co60 irradiations on single-chip devices as well as proton irradiation of a stacked DRAM module. Lastly, a discussion of test methodology is undertaken.

LaBel, K.A.; Gates, M.M.; Moran, A.K. [NASA/Goddard Space Flight Center, Greenbelt, MD (United States)] [NASA/Goddard Space Flight Center, Greenbelt, MD (United States); Kim, H.S. [Jackson and Tull, Seabrook, MD (United States)] [Jackson and Tull, Seabrook, MD (United States); Seidleck, C.M. [Hughes/STX, Seabrook, MD (United States)] [Hughes/STX, Seabrook, MD (United States); Marshall, P.; Kinnison, J.; Carkhuff, B.

1996-12-01

351

FUSION METHOD FOR THE MEASUREMENT OF PLUTONIUM IN SOILS: SINGLE-LABORATORY EVALUATION AND INTERLABORATORY COLLABORATIVE TEST  

EPA Science Inventory

This report presents the results of a single-laboratory evaluation and an interlaboratory collaborative test of a method for measuring plutonium in soil. The method employs potassium fluoride and potassium pyrosulfate fusions to decompose a 10-gram sample, barium sulfate precipit...

352

Single-Dose Oral Tolerance Test with Alternative Compounds for the Management of Adverse Reactions to Drugs  

Microsoft Academic Search

Background: Adverse reactions to drugs are common in the clinical practice. Many outpatients are frequently referred to allergists in order to determine which drugs they can safely take in the future. Objective: We set up an oral single-dose tolerance test procedure to find out for each patient one or more alternative drugs that can be taken when needed. Methods: 452

Giovanni Passalacqua; Manlio Milanese; Marcello Mincarini; Giorgio Ciprandi; Laura Guerra; Antonio Scordamaglia; Giorgio Walter Canonica

2002-01-01

353

Emerging optocoupler issues with energetic particle-induced transients and permanent radiation degradation  

SciTech Connect

Radiation-induced permanent degradation and single event transient effects for optocouplers are discussed in this paper. These two effects are independent to the first order and will be addressed separately. Displacement damage-induced degradation of optocoupler current transfer ratio is reviewed. New data are presented that show the importance of application specific testing and that generalized quantification of optocoupler CTR degradation can lead to incorrect predictions of actual circuit performance in a radiation environment. Data are given for various circuit loading and drive current parameters. Previous work that introduces the idea that two mechanisms exist for inducing transients on the optocoupler output is discussed. New data are presented that extends the evidence of this dual mechanism hypothesis. In this work measurements show that single event transient cross sections and transient propagation varies with circuit filtering. Finally, the authors discuss utilization of the optocouplers in the space environment. New data are applied to two examples: one on permanent degradation and the other on single event transient rates in high bandwidth applications.

Reed, R.A.; Barth, J.L.; LaBel, K.A. [NASA/GSFC, Greenbelt, MD (United States)] [NASA/GSFC, Greenbelt, MD (United States); Marshall, P.W.; Carts, M.A. [NRL/SFA, Largo, MD (United States)] [NRL/SFA, Largo, MD (United States); Johnston, A.H. [JPL, Pasadena, CA (United States)] [JPL, Pasadena, CA (United States); Marshall, C.J. [NRL, Washington, DC (United States)] [NRL, Washington, DC (United States); D`Ordine, M. [Ball Aerospace, Boulder, CO (United States)] [Ball Aerospace, Boulder, CO (United States); Kim, H.S. [Jackson and Tull Chartered Engineers, Washington, DC (United States)] [Jackson and Tull Chartered Engineers, Washington, DC (United States)

1998-12-01

354

Comparison of the results of short-term static tests and single-pass flow-through tests with LRM glass.  

SciTech Connect

Static dissolution tests were conducted to measure the forward dissolution rate of LRM glass at 70 C and pH(RT) 11.7 {+-} 0.1 for comparison with the rate measured with single-pass flow-through (SPFT) tests in an interlaboratory study (ILS). The static tests were conducted with monolithic specimens having known geometric surface areas, whereas the SPFT tests were conducted with crushed glass that had an uncertain specific surface area. The error in the specific surface area of the crushed glass used in the SPFT tests, which was calculated by modeling the particles as spheres, was assessed based on the difference in the forward dissolution rates measured with the two test methods. Three series of static tests were conducted at 70 C following ASTM standard test method C1220 using specimens with surfaces polished to 600, 800, and 1200 grit and a leachant solution having the same composition as that used in the ILS. Regression of the combined results of the static tests to the affinity-based glass dissolution model gives a forward rate of 1.67 g/(m{sup 2}d). The mean value of the forward rate from the SPFT tests was 1.64 g/(m{sup 2}d) with an extended uncertainty of 1.90 g/(m{sup 2}d). This indicates that the calculated surface area for the crushed glass used in the SPFT tests is less than 2% higher than the actual surface area, which is well within the experimental uncertainties of measuring the forward dissolution rate using each test method. These results indicate that the geometric surface area of crushed glass calculated based on the size of the sieves used to isolate the fraction used in a test is reliable. In addition, the C1220 test method provides a means for measuring the forward dissolution rate of borosilicate glasses that is faster, easier, and more economical than the SPFT test method.

Ebert, W. L.; Chemical Engineering

2007-01-29

355

TIA (Transient Ischemic Attack)  

MedlinePLUS

TIA (Transient Ischemic Attack) Updated:Oct 2,2014 Excerpted from “ Why Rush? ”, Stroke Connection January/February 2009 (Science update October 2012) While transient ischemic attack (TIA) is often labeled “mini-stroke,” ...

356

Transient drainage summary report  

SciTech Connect

This report summarizes the history of transient drainage issues on the Uranium Mill Tailings Remedial Action (UMTRA) Project. It defines and describes the UMTRA Project disposal cell transient drainage process and chronicles UMTRA Project treatment of the transient drainage phenomenon. Section 4.0 includes a conceptual cross section of each UMTRA Project disposal site and summarizes design and construction information, the ground water protection strategy, and the potential for transient drainage.

NONE

1996-09-01

357

10 CFR 26.165 - Testing split specimens and retesting single specimens.  

Code of Federal Regulations, 2011 CFR

10 Energy 1 2011-01-01 2011-01-01...specimens. 26.165 Section 26.165 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY...the aliquot of a single specimen are negative, the licensee or other entity—...

2011-01-01

358

Analysis, by Relap5 code, of Boron Dilution Phenomena in a Small Break Loca Transient, performed in PKL III E 2.2 Test  

Microsoft Academic Search

The present work is finalized to investigate the E2.2 thermal-hydraulics transient of the PKL III facility, which is a scaled reproduction of a typical German PWR, operated by FRAMATOME-ANP in Erlangen, Germany, within the framework of an international cooperation (OECD\\\\SETH project). The main purpose of the project is to study boron dilution events in Pressurized Water Reactors and to contribute

Giuseppe Rizzo; Giuseppe Vella

359

Complex transient epileptic amnesia  

Microsoft Academic Search

Transient epileptic amnesia is a rare but probably underrecognized form of temporal lobe epilepsy, which typically manifests as episodic isolated memory loss. Consequently, transient epileptic amnesia may be readily misdiagnosed as a nonepileptic memory dysfunction in older individuals. When appropriately recognized, it has been described as a treatment-responsive syndrome amenable to antiepileptic drugs. We describe a patient with drug-resistant transient

Ryan D. Walsh; Robert E. Wharen; William O. Tatum

2011-01-01

360

NON-DESTRUCTIVE SINGLE SHOT BUNCH LENGTH MEASUREMENTS FOR THE CLIC TEST FACILITY 3  

E-print Network

installed in the CLIC Test Facility (CTF3). Using a series of down-converting mixing stages and filters in the previous CLIC Test Facility, namely CTF2 [1,2]. Major improvements are increase of frequency reach from 90 [6], a test facility named CTF3 [7] is constructed at CERN by an international collaboration. The CTF

361

Prediction of single versus multivessel disease following myocardial infarction using 201-thallium scintigraphy and electrocardiographic stress testing  

SciTech Connect

Fifty patients were evaluated who suffered a single myocardial infarction with graded electrocardiographic stress testing, 201-thallium myocardial perfusion imaging and coronary angiography to assess the role of noninvasive indices as predictors of single versus multivessel coronary artery disease. Multivessel involvement was defined angiographically as the presence of two or more major coronary arteries with at least a 70% intraluminal diameter narrowing. Multivessel disease was defined scintigraphically as the presence of stress and/or redistribution perfusion defects in the distribution of more than one coronary artery. The results of stress electrocardiography were not useful in differentiating patients with single (9/16 positive) versus multivessel (22/34 positive) disease. The degree of exercise-induced ST-segment depression was also not helpful. Stress 201-thallium imaging did offer limited additional information with correct predictions of multivessel disease in 21 of 26 patients. Predictions of single-vessel disease were accurate in 11 of 24 patients. Eleven of these 13 incorrect predictions of single-vessel disease were due to the relative insensitivity of the thallium stress image to perceive defect in the anterior wall when the left anterior descending artery had significant obstruction at catheterization. Further refinements of stress perfusion imaging are needed before this method can be used to reliably separate patients with single and multivessel disease after myocardial infarction.

Weiss, R.J.; Morise, A.P.; Raabe, D.S. Jr.; Sbarbaro, J.A.

1983-11-01

362

Preliminary evaluation of a single-day tubeless test of pancreatic function  

Microsoft Academic Search

The test for pancreatic exocrine function using N-benzoyl-L-tyrosyl-p-aminobenzoic acid (BTP test) does not require duodenal intubation, but misleadingly abnormal results often occur in patients with liver or bowel disease because the p-aminobenzoic acid (PABA) released by chymotrypsin hydrolysis of the peptide either is not conjugated or is malabsorbed. This study evaluated a modified BTP test, using a tracer dose of

C J Mitchell; H P Field; F G Simpson; A Parkin; J Kelleher; M S Losowsky

1981-01-01

363

Race, Gender, Single-Mother Households, and Delinquency: A Further Test of Power-Control Theory  

ERIC Educational Resources Information Center

Using power-control theory as the theoretical framework, the present study examines the gender gap in delinquency for White and African American youth from single-mother households. The research is driven by the need to focus more attention on understanding how delinquency theories apply across different racial groups. Results from both bivariate…

Mack, Kristin Y.; Leiber, Michael J.

2005-01-01

364

First test of SP2: A novel active neutron spectrometer condensing the functionality of Bonner spheres in a single moderator  

NASA Astrophysics Data System (ADS)

The NESCOFI@BTF (2011-2013) international collaboration was established to develop realtime neutron spectrometers to simultaneously cover all energy components of neutron fields, from thermal up to hundreds MeV. This communication concerns a new spherical spectrometer, called SP^2, which condenses the functionality of an Extended Range Bonner Sphere Spectrometer (ERBSS) into a single moderator embedding multiple active thermal neutron detectors. The possibility of achieving the complete spectrometric information in a single exposure constitutes a great advantage compared to the ERBSS. The first experimental test of the instrument, performed with a reference 241Am-Be source in different irradiation geometries, is described. The agreement between observed and simulated response is satisfactory for all tested geometries.

Bedogni, R.; Bortot, D.; Buonomo, B.; Esposito, A.; Gómez-Ros, J. M.; Introini, M. V.; Lorenzoli, M.; Pola, A.; Sacco, D.

2014-12-01

365

Switching transients in the MFTF yin-yang coils  

SciTech Connect

This report is a study of the transients caused by the fast dump of large superconducting coils. Theoretical analysis, computer simulation, and actual measurements are used. Theoretical analysis can only be applied to the simplest of models. In the computer simulations two models are used, one in which the coil is divided into ten segments and another in which a single coil is employed. The circuit breaker that interrupts the current to the power supply, causing a fast dump, is represented by a time and current dependent conductance. Actual measurements are limited to measurements made incidental to the coils' performance tests.

Owen, E.W.; Shimer, D.W.

1982-11-02

366

DREDGED MATERIAL EFFECTS ASSESSMENT: SINGLE-SPECIES TOXICITY/BIOACCUMULATION AND MACROBENTHOS COLONIZATION TESTS  

EPA Science Inventory

Toxicity tests and bioaccumulation tests conducted according to methods established by the U.S. Environmental Protection Agency/Corps of Engineers in 1977 have been used to evaluate potential environmental impacts of ocean disposal of dredged materials. ur objective was to compar...

367

A Comparison of Reliability Estimates from Single and Double Administrations of Criterion-Referenced Tests.  

ERIC Educational Resources Information Center

Viewing the reliability for criterion-referenced tests as that of mastery classification decisions, three models for determining reliability were examined using two test administrations so that two estimates could be compared to a standard. A major purpose of the research was to determine how several reliability coefficients (coefficient kappa, an…

Schaefer, Mary M.; Gross, Susan K.

368

Long-Term and Accelerated Life Testing of a Novel Single-Wafer Vacuum Encapsulation for MEMS Resonators  

Microsoft Academic Search

We have developed a single-wafer vacuum encapsulation for microelectromechanical systems (MEMS), using a thick (20-mum) polysilicon encapsulation to package micromechanical resonators in a pressure 600 cycles of -50 to 80degC, and no measurable change in cavity pressure was seen. We have also performed accelerated leakage tests by driving hydrogen gas in and out of the encapsulation at elevated temperature. Two

Rob N. Candler; Matthew A. Hopcroft; Bongsang Kim; Woo-Tae Park; Renata Melamud; Manu Agarwal; Gary Yama; Aaron Partridge; Markus Lutz; Thomas W. Kenny

2006-01-01

369

Performance of the High-Energy Single-Event Effects Test Facility (SEETF) at Michigan State University's National Superconducting Cyclotron Laboratory (NSCL)  

NASA Technical Reports Server (NTRS)

The performance of Michigan State University's Single-Event Effects Test Facility (SEETF) during its inaugural runs is evaluated. Beam profiles and other diagnostics are presented, and prospects for future development and testing are discussed.

Ladbury, R.; Reed, R. A.; Marshall, P. W.; LaBel, K. A.; Anantaraman, R.; Fox, R.; Sanderson, D. P.; Stolz, A.; Yurkon, J.; Zeller, A. F.; Stetson, J. W.

2004-01-01

370

Quantitative test of the single-mode theory of optical bistability  

Microsoft Academic Search

The role of the transverse structure of the intracavity field in absorptive optical bistability is investigated for two-level atoms contained in a standing-wave cavity formed by spherical mirrors. Two cavity geometries are employed and differ in that one is confocal and hence degenerate with respect to transverse modes while the second is nonconfocal and closely approximates a single-mode resonator. For

L. A. Orozco; H. J. Kimble; A. T. Rosenberger

1987-01-01

371

Validation of single-edge V-notch diametral compression fracture toughness test for porous alumina  

Microsoft Academic Search

The objectives of this study were to validate a single-edge V-notch diametral compression fracture toughness technique for ceramics. Rounded notches and sharpened “V-notches” were introduced into porous, fine-grained alumina samples, and the fracture toughness results were compared. A theory linking the toughness of the material to the degree of densification fit the fracture toughness results well. The data for the

J. K. Clobes; D. J. Green

2002-01-01

372

THE DESIGN OF A SINGLE CARD TELEMETRY MODULE FOR SMART MUNITION TESTING  

Microsoft Academic Search

M\\/A-COM, Inc. has developed a miniature Tactical Telemetry Module (TTM) for medium power (500 mW and 1 W) telemetry applications. The TTM demonstrates system integration of a multi- channel PCM encoder, lower S-band transmitter, and power regulation onto a single printed wiring board (PWB). The module is smaller than a standard business card and utilizes both COTS and M\\/A-COM proprietary

Stephen Oder; Christina Dearstine; Amy Webb; John Muir; Inder Bahl; Larry Burke; Weyant Stone

373

Low-speed wind-tunnel tests of single- and counter-rotation propellers  

NASA Technical Reports Server (NTRS)

A low-speed (Mach 0 to 0.3) wind-tunnel investigation was conducted to determine the basic performance, force and moment characteristics, and flow-field velocities of single- and counter-rotation propellers. Compared with the eight-blade single-rotation propeller, a four- by four- (4 x 4) blade counter-rotation propeller with the same blade design produced substantially higher thrust coefficients for the same blade angles and advance ratios. The results further indicated that ingestion of the wake from a supporting pylon for a pusher configuration produced no significant change in the propeller thrust performance for either the single- or counter-rotation propellers. A two-component laser velocimeter (LV) system was used to make detailed measurements of the propeller flow fields. Results show increasing slipstream velocities with increasing blade angle and decreasing advance ratio. Flow-field measurements for the counter-rotation propeller show that the rear propeller turned the flow in the opposite direction from the front propeller and, therefore, could eliminate the swirl component of velocity, as would be expected.

Dunham, D. M.; Gentry, G. L., Jr.; Coe, P. L., Jr.

1986-01-01

374

Transient excitons at metal surfaces  

NASA Astrophysics Data System (ADS)

Excitons, electron-hole pairs bound by the Coulomb potential, are the fundamental quasiparticles of coherent light-matter interaction relevant for processes such as photosynthesis and optoelectronics. The existence of excitons in semiconductors is well established. For metals, however, although implied by the quantum theory of the optical response, experimental manifestations of excitons are tenuous owing to screening of the Coulomb interaction taking place on timescales of a few femtoseconds. Here we present direct evidence for the dominant transient excitonic response at a Ag(111) surface, which precedes the full onset of screening of the Coulomb interaction, in the course of a three-photon photoemission process with ~15 fs laser pulses. During this transient regime, electron-hole pair Coulomb interactions introduce coherent quasiparticle correlations beyond the single-particle description of the optics of metals that dominate the multi-photon photoemission process on the timescale of screening at a Ag(111) surface.

Cui, Xuefeng; Wang, Cong; Argondizzo, Adam; Garrett-Roe, Sean; Gumhalter, Branko; Petek, Hrvoje

2014-07-01

375

Single event effect ground test results for a fiber optic data interconnect and associated electronics  

SciTech Connect

As spacecraft unlock the potential of fiber optics for spaceflight applications, system level bit error rates become of concern to the system designer. The authors present ground test data and analysis on candidate system components.

LaBel, K.A.; Hawkins, D.K.; Cooley, J.A.; Stassinopoulos, E.G. (NASA/GSFC, Greenbelt, MD (United States)); Seidleck, C.M. (Hughes/ST Systems Corp., Greenbelt, MD (United States)); Marshall, P. (NRL/SFA, Washington, DC (United States)); Dale, C. (NRL, Washington, DC (United States)); Gates, M.M.; Kim, H.S. (Jackson and Tull, Greenbelt, MD (United States))

1994-12-01

376

Using Interval Analysis for Solving Planar Single-Facility Location Problems: New Discarding Tests  

Microsoft Academic Search

Interval analysis is a powerful tool which allows the design of branch-and-bound methods able to solve many global optimization problems. The key to the speed of those methods is the use of several tests to discard boxes or parts of boxes in which no optimal point may occur. In this paper we present three new discarding tests for two-dimensional problems

José Fernández; Blas PelegrÍn

2001-01-01

377

Transient Voltage Recorder  

NASA Technical Reports Server (NTRS)

A voltage transient recorder can detect lightning induced transient voltages. The recorder detects a lightning induced transient voltage and adjusts input amplifiers to accurately record transient voltage magnitudes. The recorder stores voltage data from numerous monitored channels, or devices. The data is time stamped and can be output in real time, or stored for later retrieval. The transient recorder, in one embodiment, includes an analog-to-digital converter and a voltage threshold detector. When an input voltage exceeds a pre-determined voltage threshold, the recorder stores the incoming voltage magnitude and time of arrival. The recorder also determines if its input amplifier circuits clip the incoming signal or if the incoming signal is too low. If the input data is clipped or too low, the recorder adjusts the gain of the amplifier circuits to accurately acquire subsequent components of the lightning induced transients.

Medelius, Pedro J. (Inventor); Simpson, Howard J. (Inventor)

2002-01-01

378

Electromagnetic Transients from Supernovae  

NASA Astrophysics Data System (ADS)

A core-collapse supernova (SN) would produce an expanding shell of charged particles which interact with the surrounding magnetic field of the progenitor star producing a transient radio pulse. Approximately one supernova event per century is expected in a galaxy. Such a pulse may be detected by a transient radio array. We present details of an ongoing such for such events by the Eight-meter-wavelength Transient Array (ETA). )

Kothari, Manthan

2010-02-01

379

Vehicle performance tests of the Ford/GE first generation single-shaft (ETX-I) alternating current propulsion system  

NASA Astrophysics Data System (ADS)

This report is concerned with the test and evaluation of the ETX-I electric test vehicle, which is a Mercury LN7 retrofitted with the single-shaft ac electric powertrain developed by Ford and General Electric under contract to the U.S. Department of Energy (DOE) during the period 1982 to 1985. The lead-acid battery used in the ETX-I was developed by Lucas Chloride Electric Vehicle (EV) Systems (LCEVS) as part of the same DOE contract. Extensive tests of the powertrain and battery were done by General Electric and Lucas Chloride before they were integrated into the ETX-I test vehicle by Ford. Ford did limited testing of the ETX-I vehicle on a chassis dynamometer to determine the energy consumption of the powertrain for several driving schedules before the vehicle was shipped to INEL for complete dynamometer testing. Ford also performed track tests with the ETX-I to determine its acceleration performance characteristics.

Crumley, R. L.; MacDowall, R. D.; Hardin, J. E.; Burke, A. F.

1989-04-01

380

Variability in creep and rupture test results in a single heat of type 304 stainless steel. R and D report LR:75:4213-01:3  

Microsoft Academic Search

Results of uniaxial creep and rupture tests, from a single heat of type ; 304 stainless steel, are examined to determine the reasons for their greater-than-; expected variability. The test results were obtained as part of a program to ; develop and verify high temperature structural design methods for liquid metal ; fast breeder reactor system components. A single heat

W. E. Leyda; C. C. Schultz

1975-01-01

381

Nearwork-induced transient myopia  

Microsoft Academic Search

The literature on nearwork-induced transient myopia (NITM) is reviewed, with NITM being defined as the short-term myopic far point shift immediately following a sustained near visual task. A majority of these investigations demonstrated the presence of NITM for a variety of test parameters, e.g., visual acuity, contrast sensitivity and far point. Overall, these studies reported relatively small myopic shifts, with

Editha Ong; Kenneth J. Ciuffreda

1995-01-01

382

Development and Testing of a Single Frequency Terahertz Imaging System for Breast Cancer Detection  

PubMed Central

The ability to discern malignant from benign tissue in excised human breast specimens in Breast Conservation Surgery (BCS) was evaluated using single frequency terahertz radiation. Terahertz (THz) images of the specimens in reflection mode were obtained by employing a gas laser source and mechanical scanning. The images were correlated with optical histological micrographs of the same specimens, and a mean discrimination of 73% was found for five out of six samples using Receiver Operating Characteristic (ROC) analysis. The system design and characterization is discussed in detail. The initial results are encouraging but further development of the technology and clinical evaluation is needed to evaluate its feasibility in the clinical environment. PMID:25055306

St. Peter, Benjamin; Yngvesson, Sigfrid; Siqueira, Paul; Kelly, Patrick; Khan, Ashraf; Glick, Stephen; Karellas, Andrew

2013-01-01

383

Antiplatelet profiles of the fixed-dose combination of extended-release dipyridamole and low-dose aspirin compared with clopidogrel with or without aspirin in patients with type 2 diabetes and a history of transient ischemic attack: A randomized, single-blind, 30-day trial  

Microsoft Academic Search

Background: Clopidogrel, aspirin (ASA), and the fixed-dose combination of extended-release dipyridamole and ASA (ER-DP+ASA) are widely used in post-stroke regimens.Objective: This study compared serial changes in multiple biomarkers of platelet activation with ER-DP+ASA and clopidogrel with or without ASA in patients with type 2 diabetes mellitus and a history of transient ischemic attack (TIA).Methods: This was a randomized, single-blind pilot

Victor L. Serebruany; Alex I. Malinin; Alex N. Pokov; Daniel F. Hanley

2008-01-01

384

Bone fracture characterization under mixed-mode I+II loading using the single leg bending test.  

PubMed

Fracture under mixed-mode I+II was induced in bovine cortical bone tissue using a developed miniaturized version of the single leg bending test (SLB). Due to the difficulty in crack length monitoring in the course of the test, an equivalent crack method based on specimen compliance and beam theory was adopted as a data reduction scheme. The method was applied to the experimental results in order to obtain the Resistance curves in each loading mode. The determined fracture energy is well described by an energetic power law whose exponent is below one, which means that the linear energetic criterion is not applicable to this material. The proposed procedure was numerically validated by means of a cohesive mixed-mode I+II damage model with bilinear softening. It was concluded that the miniaturized version of the SLB test is adequate for mixed-mode I+II fracture characterization of bone for a constant mode ratio. PMID:24715503

Pereira, F A M; de Moura, M F S F; Dourado, N; Morais, J J L; Dias, M I R

2014-11-01

385

Single neuropsychological test scores associated with rate of cognitive decline in early Alzheimer disease.  

PubMed

Alzheimer disease (AD) characteristically begins with episodic memory impairment followed by other cognitive deficits; however, the course of illness varies, with substantial differences in the rate of cognitive decline. For research and clinical purposes it would be useful to distinguish between persons who will progress slowly from persons who will progress at an average or faster rate. Our objective was to use neurocognitive performance features and disease-specific and health information to determine a predictive model for the rate of cognitive decline in participants with mild AD. We reviewed the records of a series of 96 consecutive participants with mild AD from 1995 to 2011 who had been administered selected neurocognitive tests and clinical measures. Based on Clinical Dementia Rating (CDR) of functional and cognitive decline over 2 years, participants were classified as Faster (n = 45) or Slower (n = 51) Progressors. Stepwise logistic regression analyses using neurocognitive performance features, disease-specific, health, and demographic variables were performed. Neuropsychological scores that distinguished Faster from Slower Progressors included Trail Making Test - A, Digit Symbol, and California Verbal Learning Test (CVLT) Total Learned and Primacy Recall. No disease-specific, health, or demographic variable predicted rate of progression; however, history of heart disease showed a trend. Among the neuropsychological variables, Trail Making Test - A best distinguished Faster from Slower Progressors, with an overall accuracy of 68%. In an omnibus model including neuropsychological, disease-specific, health, and demographic variables, only Trail Making Test - A distinguished between groups. Several neuropsychological performance features were associated with the rate of cognitive decline in mild AD, with baseline Trail Making Test - A performance best separating those who declined at an average or faster rate from those who showed slower progression. PMID:25131004

Parikh, Mili; Hynan, Linda S; Weiner, Myron F; Lacritz, Laura; Ringe, Wendy; Cullum, C Munro

2014-08-01

386

A performance study of some transient detectors  

Microsoft Academic Search

We present a simulation study of several different statistics applied to the detection of unknown transient signals in white Gaussian noise. The results suggest that relatively unsophisticated tests based on temporal localization of power, such as the Page (1954) test and a test based on a new statistic due to Nuttall (see NUWC-NPT Tech. Rep. 11123, 1996, and NUWC-NPT Tech.

Zhen Wang; Peter Willett

2000-01-01

387

Shake Table Tests of a Simplified Two-Story Single-Family House  

NSDL National Science Digital Library

This collection of video clips from the Caltech Woodframe Project shows what happens to a wood-frame house when it is shaken in the laboratory under conditions resembling those of an earthquake. There are both interior and exterior views, and also tests with furnishings in the house. The videos are available in two formats. There are also links to a description of the project, objectives of the testing, comments on building codes and standards in California, and the economic impacts to insurance, martgage lending, loss estimation, and disaster relief policies.

388

Testing of high-octane fuels in the single-cylinder airplane engine  

NASA Technical Reports Server (NTRS)

One of the most important properties of aviation fuels for spark-ignition engines is their knock rating. The CFR engine tests of fuels of 87 octane and above does not always correspond entirely to the actual behavior of these fuels in the airplane engine. A method is therefore developed which, in contrast to the octane number determination, permits a testing of the fuel under various temperatures and fuel mixture conditions. The following reference fuels were employed: 1) Primary fuels; isooctane and n-heptane; 2) Secondary fuels; pure benzene and synthetic benzine.

Seeber, Fritz

1940-01-01

389

Bedload transport formulae calibration using a single measurement: testing high and low  

NASA Astrophysics Data System (ADS)

Due to the difficulty in accurately predicting bedload transport using traditional equations, bedload samples are often collected in the field and used to calibrate predictions. However, sampling bedload is time consuming and expensive. In lieu of conducting an exhaustive sampling campaign in the field, some researchers have recommended collecting one to three low flow samples in the field. This work addresses the question of whether a single bedload measurement near bankfull is more successful at calibrating a predictive equation than a low flow measurement. The Pagosa Good/Fair, Wilcock Surface-based Two Fraction, and Barry et al. General Power Equation formulae are compared using a single calibration point at low flow and then another at bankfull discharge. The comparison is conducted using 2,500 measurements from a database of a total of 8,000 available measurements. The results show that a measurement at bankfull is a better predictor than a low flow measurement, but acceptable results at low flow are provided by the Pagosa and Barry formulae. This work also recommends that sampling methodology be a consideration for formula selection. In other words, certain formulae work better for Helley-Smith samplers while others are better suited for data collected in net or pit traps. For example, the predictive curve produced by the Pagosa and Barry formulae better fit Helley-Smith data than the Wilcock, which is recommended for data collected in net or pit traps.

Hinton, D. D.; Hotchkiss, R. H.

2012-12-01

390

Ris-R-1483(EN) Testing procedure for the single fiber  

E-print Network

to fiber fragmentations. Different bonding strengths between fiber and matrix result in differences is the control of the degree of adhesion between the usually more rigid fiber and the relatively ductile polymer measurement of the adhesion between a fiber and the surrounding polymer matrix. Round robin tests involving

391

Environmental assessment: Single-stage rocket technology DC-X test program  

SciTech Connect

The National Environmental Policy Act (NEPA), the Council on Environmental Quality (CEQ) regulations implementing NEPA (40 CFR Parts 1500-1508), and U.S. Department of Defense (DoD) Directive 6050.1 direct that decision-makers take into account environmental consequences when authorizing or approving major federal actions. This environmental assessment (EA) evaluates the environmental consequences of conducting activities for the SSRT test program. The purpose of the proposed action is to provide SDIO with a suborbital, recoverable rocket (SRR) capable of lifting up to 3,000 pounds of payload to an altitude of 1.5 million feet; returning to the launch site for a precise soft landing; with the capability to launch for another mission within three to seven days. To support these requirements, the proposed action involves validation and testing of a DC-X vehicle. Component assembly of the vehicle will take place at Scaled Composites, Inc., Mojave, CA; Chicago Bridge and Iron, Cordova, AL; Pratt and Whitney, West Palm Beach, FL, Aerojet, Sacramento, CA; and McDonnell Douglas Space Systems Company, Beach, CA. Static test firing activities will occur at NASA/White Sands Test Facility Huntington (WSTF), WSMR, New Mexico, and launch activities will occur at White Sands Space Harbor (WSSH), WSMR, New Mexico. No significant impacts are anticipated to the environment at the engineering contractor facilities, NASA/WSTF, or WSSH.

Not Available

1992-06-01

392

A Single-Block TRL Test Fixture for the Cryogenic Characterization of Planar Microwave Components  

NASA Technical Reports Server (NTRS)

The High-Temperature-Superconductivity (HTS) group of the RF Technology Branch, Space Electronics Division, is actively involved in the fabrication and cryogenic characterization of planar microwave components for space applications. This process requires fast, reliable, and accurate measurement techniques not readily available. A new calibration standard/test fixture that enhances the integrity and reliability of the component characterization process has been developed. The fixture consists of 50 omega thru, reflect, delay, and device under test gold lines etched onto a 254 microns (0.010 in) thick alumina substrate. The Thru-Reflect-Line (TRL) fixture was tested at room temperature using a 30 omega, 7.62 mm (300 mil) long, gold line as a known standard. Good agreement between the experimental data and the data modelled using Sonnet's em(C) software was obtained for both the return (S(sub 11)) and insertion (S( 21)) losses. A gold two-pole bandpass filter with a 7.3 GHz center frequency was used as our Device Under Test (DUT), and the results compared with those obtained using a Short-Open-Load-Thru (SOLT) calibration technique.

Mejia, M.; Creason, A. S.; Toncich, S. S.; Ebihara, B. T.; Miranda, F. A.

1996-01-01

393

RF Testing of A Single FPIX1 for BTeV James Price  

E-print Network

exercise in learning to be resourceful. Some of the pictures I was able to acquire from the manufacturer there I learned a lot about actually working in the field. So, what exactly do I mean by RF testing? Well too close to a television or monitor with a cathode ray tube, then you have some experience

Cinabro, David

394

Insight from simulations of single-well injection-withdrawal tracer tests on simple and complex fractures  

SciTech Connect

The single-well injection withdrawal (SWIW) test, a tracer test utilizing only one well, is proposed as a useful contribution to site characterization of fractured rock, as well as providing parameters relevant to tracer diffusion and sorption. The usual conceptual model of flow and solute transport through fractured rock with low matrix permeability involves solute advection and dispersion through a fracture network coupled with diffusion and sorption into the surrounding rock matrix. Unlike two-well tracer tests, results of SWIW tests are ideally independent of advective heterogeneity, channeling and flow dimension, and, instead, focus on diffusive and sorptive characteristics of tracer (solute) transport. Thus, they can be used specifically to study such characteristics and evaluate the diffusive parameters associated with tracer transport through fractured media. We conduct simulations of SWIW tests on simple and complex fracture models, the latter being defined as having two subfractures with altered rock blocks in between and gouge material in their apertures. Using parameters from the Aspo site in Sweden, we calculate and study SWIW tracer breakthrough curves (BTCs) from a test involving four days of injection and then withdrawal. By examining the peak concentration C{sub pk} of the SWIW BTCs for a variety of parameters, we confirm that C{sub pk} is largely insensitive to the fracture advective flow properties, in particular to permeability heterogeneity over the fracture plane or to subdividing the flow into two subfractures in the third dimension orthogonal to the fracture plane. The peak arrival time t{sub pk} is not a function of fracture or rock properties, but is controlled by the time schedule of the SWIW test. The study shows that the SWIW test is useful for the study of tracer diffusion-sorption processes, including the effect of the so-called flow-wetted surface (FWS) of the fracture. Calculations with schematic models with different FWS values are conducted and the possibility of direct in situ measurement of FWS with SWIW tests is demonstrated.

Tsang, C.-F.; Doughty, C.

2009-08-06

395

AN EXPERIMENTAL TEST OF SUPERRADIANCE IN A SINGLE PASS SEEDED FEL.  

SciTech Connect

Superradiance and nonlinear evolution of a FEL pulse in a single-pass FEL were experimentally demonstrated at the National Synchrotron Light Source (NSLS) Source Development Laboratory (SDL). The experiment was performed using a 1.5 ps high-brightness electron beam and a 100fs Ti:Sapphire seed laser. The seed laser and electron beam interact in the 10 meter long NISUS undulator with a period of 3.89 cm. The FEL spectrum, energy and pulse length along the undulator were measured. FEL saturation was observed, and gain of more the 200 (relative to seed laser) was measured. Both FEL spectrum widening and pulse length shortening were observed; FEL pulses as short as 65 fs FWHM were measured. The superradiance and nonlinear evolution were also simulated using the numerical code GENESIS1.3 yielding good agreement with the experimental results.

WATANABE, T.; LIU, D.; MURPHY, J.B.; ROSE, J.; SHAFTAN, T.; TSANG, T.; WANG, X.J.; YU, L.H.

2005-08-21

396

A Dedicated Search for Low Frequency Radio Transient Astrophysical Events using ETA  

E-print Network

Frequency Radio Transients, Eight-meter-wavelength Transient Array, Crab Giant Pulses, Gamma Ray Bursts-annihilation of primordial black holes (PBHs), gamma ray bursts (GRBs), and supernovae are expected to produce single

Ellingson, Steven W.

397

Low voltage pulse injection test of a single-stage 1 MV prototype induction voltage adder cell  

NASA Astrophysics Data System (ADS)

Low voltage pulse injection tests have been done on a 1 MV prototype induction cell. The tests mainly aim at measuring azimuthal uniformity of feed currents and evaluating cell electrical parameters. Tests are conducted under two cases that the cell is fed by a single pulse and two pulses, respectively. The results indicate that, in the case of the single-point feed, the best current uniformity with an azimuthal variation of 19.3% is acquired when azimuthal lines connect to cathode plates with lower half circumferences. In the case of two-pulse synchronous feed, the current uniformity becomes better, and a current with an azimuthal variation of 11.8% is achieved. Moreover, the effects of asynchronous feed on current uniformity are also experimentally investigated. The results imply that, for given injecting pulses with the duration of 70-80 ns, a time deviation less than 30 ns could be acceptable, without obvious degradation on the feed uniformity and current addition. In addition, the influences of the current uniformity and amounts of feed pulses on cell equivalent inductances are evaluated. The experiment results show that, the equivalent inductance would nearly keep a value of 130 nH as the current variation is less than 50%. However, the extreme asymmetry of feed currents or the increase of amounts of feed pulses would produce additional inductance.

Wei, Hao; Sun, Fengju; Liang, Tianxue; Yin, Jiahui; Dang, Tengfei; Zeng, Jiangtao; Cong, Peitian; Qiu, Aici

2014-08-01

398

Testing of polyimide second-stage rod seals for single-state applications in advanced aircraft hydraulic systems  

NASA Technical Reports Server (NTRS)

Machined polyimide second-stage rod seals were evaluated to determine their suitability for single-stage applications where full system pressure acts on the upstream side of the seal. The 6.35-cm (2.5-in.) K-section seal was tested in impulse screening tests where peak pressure was increased in 3.448-MPa (500-psi) increments each 20,000 cycles. Seal failure occurred at 37.92 MPa (5,500 psi), indicating a potential for acceptability in a 27.58-MPa (4,000-psi) system. Static pressurization for 600 sec at pressures in excess of 10.34 MPa (1,500 psi) revealed structural inadequacy of the seal cross section to resist fracture and extrusion. Endurance testing showed the seals capable of at least 65,000 1.27-cm (0.5-in.) cycles at 450 K (350 F) without leakage. It was concluded that the second-stage seals were proven to be exceptional in the 1.379-MPa (200-psi) applications for which they were designed, but polyimide material properties are not adequate for use in this design at pressure loading equivalent to that present in single-stage applications.

Waterman, A. W.

1977-01-01

399

In Situ Tensile Testing of Single Crystal Molybdenum Alloy Fibers with Various Dislocation Densities in a Scanning Electron Microscope  

SciTech Connect

In-situ tensile tests have been performed in a dual beam focused ion beam and scanning electron microscope on as-grown and prestrained single-crystal molybdenum-alloy (Mo-alloy) fibers. The fibers had approximately square cross sections with submicron edge lengths and gauge lengths in the range of 9-41 {mu}m. In contrast to previously observed yield strengths near the theoretical strength of 10 GPa in compression tests of {approx}1-3-{mu}m long pillars made from similar Mo-alloy single crystals, a wide scatter of yield strengths between 1 and 10 GPa was observed in the as-grown fibers tested in tension. Deformation was dominated by inhomogeneous plastic events, sometimes including the formation of Lueders bands. In contrast, highly prestrained fibers exhibited stable plastic flow, significantly lower yield strengths of {approx}1 GPa, and stress-strain behavior very similar to that in compression. A simple, statistical model incorporating the measured dislocation densities is developed to explain why the tension and compression results for the as-grown fibers are different.

George, Easo P [ORNL; Johanns, K. [University of Tennessee, Knoxville (UTK); Sedlmayr, A. [Karlsruhe Institute of Technology, Karlsruhe, Germany; Phani, P. Sudharshan [University of Tennessee, Knoxville (UTK); Monig, R. [Karlsruhe Institute of Technology, Karlsruhe, Germany; Kraft, O. [Karlsruhe Institute of Technology, Karlsruhe, Germany; Pharr, George M [University of Tennessee, Knoxville (UTK) & Oak Ridge National Laboratory (ORNL)

2012-01-01

400

Assessing Potential Impacts of CO2 Leakage on Shallow Groundwater Quality in the SECARB Phase III Early Test site Using Single-well Push-Pull Tests  

NASA Astrophysics Data System (ADS)

A single-well push-pull test was conducted in the Cranfield shallow aquifer, the SECARB Phase III early test site, for assessing potential impacts of CO2 leakage on groundwater quality. A total of 3800 liter of groundwater equilibrated with CO2 gas at a partial pressure of 1.105 Pa was injected into a confined sand interval at ~ 70 m depth. NaBr solution was added to the injected solution as tracer. The injected groundwater incubated within the interval for about two days. Chemical parameters (pH, temperature, alkalinity, and electric conductivity) were measured on-site and water samples were collected for chemical (major ions, trace elements, and dissolved inorganic carbon, DIC) as well as for stable carbon isotopic analyses. Mineralogical analyses using XR-D and SEM techniques indicate that aquifer sediments are dominated by silicates. Concentrations of the Br tracer in the recovered samples show mixing of background water with the injected solution. Major ions, especially, Ca, Mg, K, and Si show obvious enrichment, indicating that mobilization of these ions occurred from aquifer sediments to groundwater and may be dominated by dissolution of silicates and possible carbonate minerals. ?13C of DIC of the recovered samples may also suggest potential dissolution of carbonates. Concentrations of trace elements show mobilization after injection of CO2 enriched groundwater. Mobilization of trace elements could be due to co-dissolution of silicates and carbonates and desorption from the surface of aquifer sediments. However, mass balance calculations suggest that ion mobilization is limited and; therefore, potential risks of CO2 are low, especially for arsenic and lead with concentrations in the recovered samples ~30 times less than the EPA maximum contamination level. Results of the single-well push-pull test were also compared to a laboratory batch experiment of water-rock-CO2 interactions. Overall reaction rates of most ions estimated are higher in the batch experiments than in the push-pull test. Such differences could be due to larger reactive surface area in the batch experiment. Our study shows single-well push-pull tests appear to be a valuable approach for assessing potential impacts of CO2 leakage on drinking water resources at geological CO2 sequestration sites.

Yang, C.; Mickler, P. J.; Reedy, R. C.; Scanlon, B. R.

2012-12-01

401

Expression of Interest for a Full-Scale Detector Engineering Test and Test Beam Calibration of a Single-Phase LAr TPC  

E-print Network

Following the recommendation of the U.S. Particle Physics Project Prioritization Panel[1], Fermilab is working with the world neutrino community, CERN, and others to establish “a new international collaboration to design and execute a highly capable Long-Baseline Neutrino Facility (LBNF) hosted by the U.S.” This new collaboration, which is expected to be formed during the next several months, will combine, among others, groups that have been developing both single-phase and dual-phase LAr TPC detectors for long-baseline physics, mainly from the LBNE and LBNO collaborations respectively. This Expression of Interest regards a proposed full-scale prototype and beam test of the LBNE-design single-phase detector, utilizing the CERN Neutrino Platform[2] that was recently approved as part of the Medium-Term Plan (MTP) [3]. Once the LBNF collaboration is formed, it is expected that development of both single- and dual-phase detectors will come under the umbrella of the new collaboration.

Leigui de Oliveira, M A

2014-01-01

402

Microprocessor-Based Multichannel Transient Recorder  

Microsoft Academic Search

Data acquisition of fast time varying transient phenomena relevant to structural dynamics and aerodynamic wind tunnel testing pose a number of problems such as speed, retrieval of data for analysis, number of channels, etc. To overcome these limitations, a software-based high-speed Multichannel Transient Data Acquisition system has been designed and developed. This system is built around the Burr-Brown SDM-853 Module.

P. N. Joshi; V. Mahalingam; S. Renganathan

1987-01-01

403

Toxicity evaluation of single and mixed antifouling biocides using the Strongylocentrotus intermedius sea urchin embryo test.  

PubMed

The present study evaluated the single and mixed toxicities of commonly used antifouling biocides (copper pyrithione, Sea nine 211, dichlofluanid, tolylfluanid, and Irgarol 1051) on the early embryogenesis of sea urchin Strongylocentrotus intermedius. Their toxicities were quantified in terms of the median effective concentration (EC50) reducing the embryogenesis success by 50%. For individual biocides to the embryos, the toxicity was in order of copper pyrithione>Sea nine 211>?tolylfluanid>dichlofluanid>Irgarol 1051. The toxicities of mixture (binary, ternary, quaternary, and quinary) of compounds, evaluated by toxic unit, additivity index, and mixture toxicity index, showed that the copper pyrithione-Sea nine 211 combination was the most toxic with the EC50 value of 7.87 nM in all mixtures. Synergistic enhancements of toxicity were observed for all mixtures except the combination of tolylfluanid-Sea nine 211, revealing antagonistic effect. Both the concentration addition and independent action concepts failed to accurately predict the mixture toxicities of the antifouling combinations; thus, a new log K(OW)-based model was developed to predict the combined toxicities of these antifouling chemicals, which were capable of predicting the mixture toxicities of antifouling biocides (R(2)=0.33). PMID:21154844

Wang, Heng; Li, Yan; Huang, Honghui; Xu, Xue; Wang, Yonghua

2011-03-01

404

Mutation analysis of androgen receptor gene: Multiple uses for a single test.  

PubMed

Androgen receptor gene mutations are one of the leading causes of disorders of sex development (DSD) exhibited by sexual ambiguity or sex reversal. In this study, 2 families with patients whom diagnosed clinically as androgen insensitivity syndrome (AIS) were physically and genetically examined. This evaluation carried out by cytogenetic and molecular analysis including karyotype and sequencing of SRY and AR genes. In family 1, two brothers and their mother were hemizygous and heterozygous respectively for c.2522G>A variant, while one of their healthy brother was a completely normal hemizygote. Family 2 assessment demonstrated the c.639G>A (rs6152) mutation in two siblings who were reared as girls. The SRY gene was intact in all of the study's participants. Our findings in family 1 could be a further proof for the pathogenicity of the c.2522G>A variant. Given the importance of AR mutations in development of problems such as sex assignment in AIS patients, definitive diagnosis and phenotype-genotype correlation could be achieved by molecular genetic tests that in turn could have promising impacts in clinical management and also in prenatal diagnosis of prospect offspring. In this regard, phenotype-genotype correlation could be helpful and achieved by molecular genetic tests. This could influence the clinical management of the patients as well as prenatal diagnosis for the prospective offspring. PMID:25241384

Shojaei, Azadeh; Behjati, Farkhondeh; Ebrahimzadeh-Vesal, Reza; Razzaghy-Azar, Maryam; Derakhshandeh-Peykar, Pupak; Izadi, Pantea; Kajbafzadeh, Abdol-Mohammad; Dowlatih, Mohammad-Ali; Karami, Fatemeh; Tavakkoly-Bazzaz, Javad

2014-12-01

405

Monitoring bioaugmenation with single-well push-pull tests in sediment systems contaminated with trichloroethene.  

PubMed

Bioaugmentation to enhance the rate and extent of reductive dechlorination of chlorinated ethenes was investigated in intermediate ( approximately 1 m) scale physical aquifer models (PAMs) designed to simulate the groundwater flow field near an injection well. Push-pull tests were used to quantify the reductive dechlorination of injected trichloroethene (TCE) and trichlorofluoroethene (TCFE) in prepared sediment packs with and without an added dechlorinating culture containing Dehalococcoides spp. Distribution of the added culture throughout the sediment pack was confirmed by microscopic observation. Repeated additions of TCE (100-350 microM) were completely transformed to ethene in 14 days and a subsequent TCFE addition (114 microM) was completely transformed to fluoroethene (FE) in 24 days. Similar transformation rates, product distributions, and time courses for TCE and TCFE transformation were observed when these compounds were added together at similar initial concentrations. In the control PAM (nonbioaugmented), TCE and TCFE were transformed to only cis-DCE and cis-DCFE, respectively, and transformation rates were 6-12 times slower than those in the bioaugmented PAM. The use of TCFE for push-pull tests is shown to be an effective tool for detecting and quantifying the effects of bioaugmentation on TCE transformation. PMID:20030401

Lee, Jae-Hyuk; Dolan, Mark; Field, Jennifer; Istok, Jonathan

2010-02-01

406

Initial testing of a Compact Crystal Positioning System for the TOPAZ Single-Crystal Diffractometer at the Spallation Neutron Source  

SciTech Connect

A precise, versatile, and automated method of orienting a sub-millimeter crystal in a focused neutron beam is required for e cient operation of the TOPAZ Single Crystal Di ractometer at the Spallation Neutron Source at Oak Ridge National Laboratory. To ful ll this need, a Compact Crystal Positioning System (CCPS) has been developed in collaboration with Square One Systems Design in Jackson, Wyoming. The system incorporates a tripod design with six vacuum-compatible piezoelectric linear motors capable of < 1 m resolution. National Instruments LabVIEW provides a means of system automation while at the same time accommodating the modular nature of the SNS sample environment control software for straightforward system integration. Initial results in a cryogenic test environment will be presented, as well as results from ambient tests performed at the Advanced Photon Source at Argonne National Laboratory.

Frost, Matthew J [ORNL; Austin, Michael D [ORNL; Viola, Robert [ORNL; Thomison, Jack [ORNL; Carmen, Peter [Square One Systems Design; Hoffmann, Christina [ORNL; Miller, Echo M [ORNL; Mosier, Lisa B [ORNL; Overbay, Mark A [ORNL

2009-01-01

407

Detecting leaks in pressurised pipes by means of transients La détection des fuites dans des tubes pressurisés par des tests en régime non  

Microsoft Academic Search

Reliable and quick techniques are needed to locate and estimate leaks in pressurised pipe systems in order to reduce water loss as much as possible. The aim of the present paper is to show that the use of unsteady-state tests, which give rise to small overpressure, can be considered as an appropriate method. During these tests, it is necessary to

BRUNO BRUNONE; MARCO FERRANTE

408

Prototype powerline transient source and direction of propagation detector. Final technical note, Jul 1973Sep 1974  

Microsoft Academic Search

Random impulse voltage transients that occur on electrical power distribution systems can cause physical damage to critical loads, resulting in operational failure. There are numerous transient detection devices, but until recently no device could determine the direction of propagation of transients on a powerline. This report is an evaluation of two prototype transient-direction detectors. Tests revealed they provide a simple

M. N. Smith; K. T. Huang

1975-01-01

409

Transient fault modeling and fault injection simulation  

E-print Network

An accurate transient fault model is presented in this thesis. A 7-term exponential current upset model is derived from the results of a device-level, 3-dimensional, single-event-upset simulation. A curve-fitting algorithm is used to extract...

Yuan, Xuejun

2012-06-07

410

Unraveling sexual associations in contact and noncontact child sex offenders using the single category - implicit association test.  

PubMed

Previous studies found associations between children and sex in child sex offenders (CSOs) using the Implicit Association Test (IAT). We used a modification of this task, the Single Category-Implicit Association Test (SC-IAT) to unravel child-sex associations in CSOs. Using the SC-IAT, we were able to test whether CSOs indeed hold stronger child-sex associations relative to adult-sex associations, compared to adult sex offenders and nonoffenders. Furthermore, we examined whether contact CSOs differed from noncontact CSOs in their child-sex associations. The hypothesis that CSOs would have stronger child-sex associations, relative to their adult-sex associations, than adult sex offenders and nonoffenders was confirmed. No difference between contact CSOs and noncontact CSOs was found. Although the Sex SC-IAT was able to distinguish CSOs from nonoffenders, the sensitivity and specificity of the test was poor (AUC of .65) and needs refinement. The results of this study support the existence of a child-sex association as a distinctive characteristic of CSOs. These findings are discussed in the context of theories on deviant cognitions in CSOs and risk for sexual offending. PMID:23125056

Hempel, I S; Buck, N M L; Goethals, K R; van Marle, H J C

2013-10-01

411

Transient nucleation in glasses  

NASA Technical Reports Server (NTRS)

Nucleation rates in condensed systems are frequently not at their steady state values. Such time dependent (or transient) nucleation is most clearly observed in devitrification studies of metallic and silicate glasses. The origin of transient nucleation and its role in the formation and stability of desired phases and microstructures are discussed. Numerical models of nucleation in isothermal and nonisothermal situations, based on the coupled differential equations describing cluster evolution within the classical theory, are presented. The importance of transient nucleation in glass formation and crystallization is discussed.

Kelton, K. F.

1991-01-01

412

Test plan for single well injection/extraction characterization of DNAPL  

SciTech Connect

Soils and groundwater beneath an abandoned Process sewer line in the A/M Area of the Savannah River Site (SRS) contain elevated levels of volatile organic compounds, specifically trichloroethylene (TCE) and tetrachloroethylene (PCE), two common chlorinated solvents. These compounds have low aqueous solubilities, thus when released to the subsurface in sufficient quantity, tend to exist as immiscible fluids or nonaqueous phase liquids (NAPLs). Because chlorinated solvents are also denser than water, they are referred to by the acronym DNAPLS, or dense non aqueous Phase liquids. Technologies targeted at the efficient characterization or removal of DNAPL are not currently proven. For example, most DNAPL studies rely on traditional soil and water sampling and the fortuitous observation of immiscible solvent. Once DNAPL is identified, soil excavation (which is only applicable to small contained spill sites) is the only ``proven`` cleanup method. New cleanup approaches based on enhanced removal by surfactants and/or alcohols have been proposed and tested at the pilot scale. As described below, carefully designed experiments similar to the enhanced removal methods may provide important characterization information on DNAPLs.

Looney, B.B.; Jerome, K.M.; Burdick, S.; Rossabi, J.; Jarosch, T.R.; Eddy-Dilek, C.A.

1995-12-01

413

A New Parameter to Assess Hydromechanical Effect in Single-hole Hydraulic Testing and Grouting  

SciTech Connect

Grouting or filling of the open voids in fractured rock is done by introducing a fluid, a grout, through boreholes under pressure. The grout may be either a Newtonian fluid or a Bingham fluid. The penetration of the grout and the resulting pressure profile may give rise to hydromechanical effects, which depends on factors such as the fracture aperture, pressure at the borehole and the rheological properties of the grout. In this paper, we postulate that a new parameter, {angstrom}, which is the integral of the fluid pressure change in the fracture plane, is an appropriate measure to describe the change in fracture aperture volume due to a change in effective stress. In many cases, analytic expressions are available to calculate pressure profiles for relevant input data and the {angstrom} parameter. The approach is verified against a fully coupled hydromechanical simulator for the case of a Newtonian fluid. Results of the verification exercise show that the new approach is reasonable and that the {angstrom}-parameter is a good measure for the fracture volume change: i.e., the larger the {angstrom}-parameter, the larger the fracture volume change, in an almost linear fashion. To demonstrate the application of the approach, short duration hydraulic tests and constant pressure grouting are studied. Concluded is that using analytic expressions for penetration lengths and pressure profiles to calculate the {angstrom} parameter provides a possibility to describe a complex situation and compare, discuss and weigh the impact of hydromechanical couplings for different alternatives. Further, the analyses identify an effect of high-pressure grouting, where uncontrolled grouting of larger fractures and insufficient (or less-than-expected) sealing of finer fractures is a potential result.

Rutqvist, Jonny; Fransson, A.; Tsang, C.-F.; Rutqvist, J.; Gustafson, G.

2007-09-01

414

Screening for Aspirin Responsiveness After Transient Ischemic Attack and Stroke Comparison of 2 Point-of-Care Platelet Function Tests With Optical Aggregometry  

Microsoft Academic Search

Background and Purpose—Recent studies suggest that patients who do not respond to aspirin (ASA) therapy may be at increased risk of ischemic vascular events. The availability of simple to use point-of-care (POC) platelet function tests now potentially allows aspirin nonresponsiveness to be identified in routine clinical practice. However, there are very few data on whether the different tests produce consistent

Paul Harrison; Helen Segal; Kevin Blasbery; Charlene Furtado; Louise Silver; Peter M. Rothwell

415

Transient Scrotal Hyperthermia Induces Lipid Droplet Accumulation and Reveals a Different ADFP Expression Pattern between the Testes and Liver in Mice  

PubMed Central

Background In most mammals, the testes provide a stable environment for spermatogenesis, which depends on a lower temperature than the core body temperature. It has been reported that mild testicular heating safely and reversibly suppresses spermatogenesis, and is under consideration for its potential application as a male contraceptive. Previously, we focused on the molecular mechanism of germ cell apoptosis and anti-apoptotic factors induced by heat treatment in humans and mice. However, the recovery process remains under investigation. Results In this study, we found that lipid droplets in mouse testes are dramatically increased after a brief period of scrotal hyperthermia, and gradually dissipate following temperature normalization. Analysis of the human testis proteome revealed nine proteins associated with lipid droplets. Two of them, ADFP (also known as ADRP and PLIN2) and TIP47 (also known as PLIN3) may participate in acute lipid droplet formation in mammalian testes. We show that Adfp expression is upregulated after scrotal heat treatment in mice. Surprisingly, we find Adfp lacking its 5?-UTR is observed in Adfp?1/?1 mouse testes, but is not detectable in liver. Conclusions These results reveal testis Adfp transcriptional regulation is tissue-specific, and is associated with lipid droplet accumulation induced by heat. The results also indicate that the testes could retain functional proteins through testes-specific transcriptional regulation. PMID:23056214

Liu, Mingxi; Qi, Lin; Zeng, Yan; Yang, Yang; Bi, Ye; Shi, Xiaodan; Zhu, Hui; Zhou, Zuomin; Sha, Jiahao

2012-01-01

416

Femtosecond Transient Imaging  

E-print Network

This thesis proposes a novel framework called transient imaging for image formation and scene understanding through impulse illumination and time images. Using time-of-flight cameras and multi-path analysis of global light ...

Kirmani, Ahmed (Ghulam Ahmed)

2010-01-01

417

Transient Response Analysis  

NASA Technical Reports Server (NTRS)

Transient Response Analysis Program, TRAP aids in analysis of frequency response of force-transmission and shock-damping devices. Devices analyzed with TRAP include hydraulic actuators, automotive shock absorbers and electromechanical actuators.

Blackman, L. D.

1985-01-01

418

Transient monocular visual loss.  

PubMed

Transient monocular visual loss may be caused by a variety of ophthalmic and systemic conditions. Management depends on identifying the cause. Embolic occlusions of arteries supplying the eye are a most important cause. Such emboli often arise from the heart, aorta, and internal carotid arteries. The most common embolic substances are white platelet-fibrin and red erythrocyte-fibrin thrombi, cholesterol crystals, and calcific particles. Retinal vasoconstriction is another important cause of transient monocular visual loss. The conditions that cause anterior ischemic optic neuropathy may occasionally cause transient visual loss. Transient monocular visual loss may also be related to conditions that cause papilledema and some conditions intrinsic to the eye, such as optic disk drusen and colobomas. PMID:17540127

Amick, Amy; Caplan, Louis R

2007-01-01

419

Complex transient epileptic amnesia.  

PubMed

Transient epileptic amnesia is a rare but probably underrecognized form of temporal lobe epilepsy, which typically manifests as episodic isolated memory loss. Consequently, transient epileptic amnesia may be readily misdiagnosed as a nonepileptic memory dysfunction in older individuals. When appropriately recognized, it has been described as a treatment-responsive syndrome amenable to antiepileptic drugs. We describe a patient with drug-resistant transient epileptic amnesia treated with unilateral temporal lobectomy. Prolonged postictal slowing in the mesial temporal structures was evident on invasive electroencephalography 5 hours after the occurrence of a brief focal seizure. These findings support the theory of a Todd phenomenon as the underlying pathophysiological mechanism in transient epileptic amnesia. PMID:21262589

Walsh, Ryan D; Wharen, Robert E; Tatum, William O

2011-02-01

420

Gamma ray transients  

NASA Technical Reports Server (NTRS)

The discovery of cosmic gamma ray bursts was made with systems designed at Los Alamos Laboratory for the detection of nuclear explosions beyond the atmosphere. HELIOS-2 was the first gamma ray burst instrument launched; its initial results in 1976, seemed to deepen the mystery around gamma ray transients. Interplanetary spacecraft data were reviewed in terms of explaining the behavior and source of the transients.

Cline, Thomas L.

1987-01-01

421

Multiresolution transient detection  

Microsoft Academic Search

Designs and studies the performance of a multiresolution-based transient detector. The transients the authors are interested in consist of wide-band, pulse-like, coherent structures in a turbulent flow. To take advantage of the fast pyramidal wavelet algorithm, an important point when processing large amounts of experimental data, the detector makes use of the discrete wavelet transform. The authors show how the

Patrice Abry; Patrick Flandrin

1994-01-01

422

Thermal single-well injection-withdrawal tracer tests for determining fracture-matrix heat transfer area  

SciTech Connect

Single-well injection-withdrawal (SWIW) tracer tests involve injection of traced fluid and subsequent tracer recovery from the same well, usually with some quiescent time between the injection and withdrawal periods. SWIW are insensitive to variations in advective processes that arise from formation heterogeneities, because upon withdrawal, fluid parcels tend to retrace the paths taken during injection. However, SWIW are sensitive to diffusive processes, such as diffusive exchange of conservative or reactive solutes between fractures and rock matrix. This paper focuses on SWIW tests in which temperature itself is used as a tracer. Numerical simulations demonstrate the sensitivity of temperature returns to fracture-matrix interaction. We consider thermal SWIW response to the two primary reservoir improvements targeted with stimulation, (1) making additional fractures accessible to injected fluids, and (2) increasing the aperture and permeability of pre-existing fractures. It is found that temperature returns in SWIW tests are insensitive to (2), while providing a strong signal of more rapid temperature recovery during the withdrawal phase for (1).

Pruess, K.; Doughty, C.

2010-01-15

423

Transient behavior of superheated water jets boiling  

NASA Astrophysics Data System (ADS)

Superheated water flowing out from high-pressure chamber through short cylindrical and slot channel has been studied experimentally. Relation of vaporization mechanisms in superheated liquid (boiling in single, not interacting centers, intense heterogeneous vaporization, and homogeneous fluctuating nucleation) and respective forms of superheated water jets has been determined. Temperature intervals with transient behavior of boiling have been determined. It is shown that at transient behavior of boiling the amplitude of pulsations of jet parameters increases, and in the spectra of pulsation power, the low-frequency component 1/ f appears.

Reshetnikov, A. V.; Busov, K. A.; Mazheiko, N. A.; Skokov, V. N.; Koverda, V. P.

2012-06-01

424

Genotoxic effects of chemicals in the single cell gel (SCG) test with human blood cells in relation to the induction of sister-chromatid exchanges (SCE)  

Microsoft Academic Search

In a comparative study, henzo[a]pyrene (BaP), cyclophosphamide (CP), N-methyl-N?-nitro-N-nitrosoguanidine (MNNG) and tetrachloroethylene (PER) were tested for their ability to induce genotoxic effects in the single cell gel (SCG) test and the sister-chromatid exchange (SCE) test with human blood cells. MNNG as well as S9 mix activated BaP- and CP-induced DNA effects in both tests in a dose-dependent manner. While the

Andreas Hartmann; Günter Speit

1995-01-01

425

Single Pass Flow-Through (SPFT) Test Results of Fluidized Bed Steam Reforming (FBSR) Waste Forms used for LAW Immobilization  

SciTech Connect

Several supplemental technologies for treating and immobilizing Hanford low activity waste (LAW) are being evaluated. One such immobilization technology being considered is the Fluidized Bed Steam Reforming (FBSR) granular product. The FBSR granular product is composed of insoluble sodium aluminosilicate (NAS) feldspathoid minerals. Production of the FBSR mineral product has been demonstrated both at the industrial and laboratory scale. Single-Pass Flow-Through (SPFT) tests at various flow rates have been conducted with the granular products fabricated using these two methods. Results show that the materials exhibit a relatively low forward dissolution rate on the order of 10-3 g/(m2d) with the material made in the laboratory giving slightly higher values.

Neeway, James J.; Qafoku, Nikolla; Williams, Benjamin D.; Valenta, Michelle M.; Cordova, Elsa A.; Strandquist, Sara C.; Dage, DeNomy C.; Brown, Christopher F.

2012-03-20