Science.gov

Sample records for single transient test

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

    NASA Technical Reports Server (NTRS)

    Rodriguez, Jose I.; Mills, Anthony F.

    1990-01-01

    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.

  2. Single-Event Transient Testing of the Crane Aerospace and Electronics SMHF2812D Dual DC-DC Converter

    NASA Technical Reports Server (NTRS)

    Casey, Megan

    2015-01-01

    The purpose of this testing was to characterize the Crane Aerospace & Electronics (Crane) Interpoint SMHF2812D for single-event transient (SET) susceptibility. These data shall be used for flight lot evaluation, as well as qualification by similarity of the SMHF family of converters, all of which use the same active components.

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

    NASA Technical Reports Server (NTRS)

    Adell, Philippe; Allen, Gregory

    2013-01-01

    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

  4. Effect of transient liquid phase (TLP) bonding on the ductility of a Ni-base single crystal superalloy in a stress rupture test

    SciTech Connect

    Liu, J.D. Jin, T.; Zhao, N.R.; Wang, Z.H.; Sun, X.F.; Guan, H.R.; Hu, Z.Q.

    2008-01-15

    A Ni-base single crystal superalloy was transient liquid phase (TLP) bonded using a Ni-Cr-B amorphous foil at 1230 deg. C for 8 h. Stress rupture tests of the TLP joint and a matrix sample were carried out at 982 deg. C/248 MPa and 1010 deg. C/248 MPa. The microstructures and fracture surfaces were studied using scanning electron microscopy (SEM). Transmission electron microscopy (TEM) investigations were performed after creep rupture testing to examine the deformation substructures. The results show that the stress rupture ductility of TLP joints is significantly decreased compared to the matrix sample. This reduction of the ductility of TLP joints can be attributed to solid solution strengthening by boron atoms, subgrain boundaries formed in the bonding zone and the concentration of creep cavities formed during the last stage of the stress rupture test.

  5. Igniter heater EMI transient test

    NASA Technical Reports Server (NTRS)

    Cook, M.

    1989-01-01

    Testing to evaluate Redesigned Solid Rocket Motor igniter heater electromagnetic interference (EMI) effects on the Safe and Arm (S and A) device was completed. It was suspected that EMI generated by the igniter heater and it's associated electromechanical relay could cause a premature firing of the NASA Standard Initiators (NSIs) inside the S and A. The maximum voltage induced into the NSI fire lines was 1/4 of the NASA specified no-fire limit of one volt (SKB 26100066). As a result, the igniter heaters are not expected to have any adverse EMI effects on the NSIs. The results did show, however, that power switching causes occasional high transients within the igniter heater power cable. These transients could affect the sensitive equipment inside the forward skirt. It is therefore recommended that the electromechanical igniter heater relays be replaced with zero crossing solid state relays. If the solid state relays are installed, it is also recommended that they be tested for EMI transient effects.

  6. Transient Pressure Test Article Test Program

    NASA Technical Reports Server (NTRS)

    Vibbart, Charles M.

    1989-01-01

    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.

  7. Transient Rayleigh scattering from single semiconductor nanowires

    SciTech Connect

    Montazeri, Mohammad; Jackson, Howard E.; Smith, Leigh M.; Yarrison-Rice, Jan M.; Kang, Jung-Hyun; Gao, Qiang; Tan, Hark Hoe; Jagadish, Chennupati

    2013-12-04

    Transient Rayleigh scattering spectroscopy is a new pump-probe technique to study the dynamics and cooling of photo-excited carriers in single semiconductor nanowires. By studying the evolution of the transient Rayleigh spectrum in time after excitation, one can measure the time evolution of the density and temperature of photo-excited electron-hole plasma (EHP) as they equilibrate with lattice. This provides detailed information of dynamics and cooling of carriers including linear and bimolecular recombination properties, carrier transport characteristics, and the energy-loss rate of hot electron-hole plasma through the emission of LO and acoustic phonons.

  8. Thermophysical property testing using transient techniques

    NASA Astrophysics Data System (ADS)

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

    1984-06-01

    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.

  9. Analysis and RHBD technique of single event transients in PLLs

    NASA Astrophysics Data System (ADS)

    Zhiwei, Han; Liang, Wang; Suge, Yue; Bing, Han; Shougang, Du

    2015-11-01

    Single-event transient susceptibility of phase-locked loops has been investigated. The charge pump is the most sensitive component of the PLL to SET, and it is hard to mitigate this effect at the transistor level. A test circuit was designed on a 65 nm process using a new system-level radiation-hardening-by-design technique. Heavy-ion testing was used to evaluate the radiation hardness. Analyses and discussion of the feasibility of this method are also presented.

  10. Single Event Transients in Linear Integrated Circuits

    NASA Technical Reports Server (NTRS)

    Buchner, Stephen; McMorrow, Dale

    2005-01-01

    On November 5, 2001, a processor reset occurred on board the Microwave Anisotropy Probe (MAP), a NASA mission to measure the anisotropy of the microwave radiation left over from the Big Bang. The reset caused the spacecraft to enter a safehold mode from which it took several days to recover. Were that to happen regularly, the entire mission would be compromised, so it was important to find the cause of the reset and, if possible, to mitigate it. NASA assembled a team of engineers that included experts in radiation effects to tackle the problem. The first clue was the observation that the processor reset occurred during a solar event characterized by large increases in the proton and heavy ion fluxes emitted by the sun. To the radiation effects engineers on the team, this strongly suggested that particle radiation might be the culprit, particularly when it was discovered that the reset circuit contained three voltage comparators (LM139). Previous testing revealed that large voltage transients, or glitches appeared at the output of the LM139 when it was exposed to a beam of heavy ions [NI96]. The function of the reset circuit was to monitor the supply voltage and to issue a reset command to the processor should the voltage fall below a reference of 2.5 V [PO02]. Eventually, the team of engineers concluded that ionizing particle radiation from the solar event produced a negative voltage transient on the output of one of the LM139s sufficiently large to reset the processor on MAP. Fortunately, as of the end of 2004, only two such resets have occurred. The reset on MAP was not the first malfunction on a spacecraft attributed to a transient. That occurred shortly after the launch of NASA s TOPEX/Poseidon satellite in 1992. It was suspected, and later confirmed, that an anomaly in the Earth Sensor was caused by a transient in an operational amplifier (OP-15) [KO93]. Over the next few years, problems on TDRS, CASSINI, [PR02] SOHO [HA99,HA01] and TERRA were also attributed to transients. In some cases, such events produced resets by falsely triggering circuits designed to protect against over- voltage or over-current. On at least three occasions, transients caused satellites to switch into "safe mode" in which most of the systems on board the satellites were powered down for an extended period. By the time the satellites were reconfigured and returned to full operational state, much scientific data had been lost. Fortunately, no permanent damage occurred in any of the systems and they were all successfully re-activated.

  11. Transient thermoelectric effect in bismuth single crystals

    NASA Astrophysics Data System (ADS)

    Sasaki, M.; Tai, G. X.; Inoue, M.; Bidadi, H.

    1994-05-01

    The photo-induced transient thermoelectric effect (TTE) has been measured for bismuth single crystals along nearly the X and Y axes over the temperature range 6-300 K and time range 50 ns-2 ms. The decay curves of the TTE voltages are characterized by multiple relaxation processes for thermal diffusions of photogenerated electrons and holes. From the analysis of the relaxation times, we have evaluated the carrier mobilities and their effective masses of each carrier pocket at the L and T points based on the existing band model; in particular, we have found an additional hole pocket at the L point lying below the Fermi energy. This TTE technique is shown to be useful for understanding electronic properties of a multicarrier system.

  12. Transient Sub-Poissonian Distribution for Single-Mode Lasers

    NASA Technical Reports Server (NTRS)

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

    1996-01-01

    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.

  13. Transient tests on an MHD thruster

    SciTech Connect

    Pierson, E.S. . Dept. of Engineering); Libera, J.; Petrick, M. . Energy Systems Div.)

    1993-01-01

    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.

  14. Future Transient Testing of Advanced Fuels

    SciTech Connect

    Jon Carmack

    2009-09-01

    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.

  15. Results from transient tests and spherical valve closure tests, Raccoon Mountain Pumped-Storage Plant

    SciTech Connect

    March, P.A.

    1984-09-01

    Tests were conducted at the Raccoon Mountain Pumped-Storage Plant to obtain data on hydraulic system characteristics during transient-state operation, to compare measured values for system pressures and surge levels with design values, to provide information for review of hydaulic transient computations, and to provide confirmation that the spherical valves are capable of shutting off plant flow under emergency conditions. The tests included single-unit load rejection, single-unit pump power loss, multi-unit emergency shutdown from generating, multi-unit emergency shutdown from pumping, and spherical valve closure.

  16. Sensitive, time-resolved, broadband spectroscopy of single transient processes

    NASA Astrophysics Data System (ADS)

    Fjodorow, Peter; Baev, Ivan; Hellmig, Ortwin; Sengstock, Klaus; Baev, Valery M.

    2015-09-01

    Intracavity absorption spectroscopy with a broadband Er3+-doped fiber laser is applied to time-resolved measurements of transient gain and absorption in electrically excited Xe and Kr plasmas. The achieved time resolution for broadband spectral recording of a single process is 25 s. For pulsed-periodic processes, the time resolution is limited by the laser pulse duration, which is set here to 3 s. This pulse duration also predefines the effective absorption path length, which amounts to 900 m. The presented technique can be applied to multicomponent analysis of single transient processes such as shock tube experiments, pulse detonation engines, or explosives.

  17. Transient well testing in two-phase geothermal reservoirs

    SciTech Connect

    Aydelotte, S.R.

    1980-03-01

    A study of well test analysis techniques in two-phase geothermal reservoirs has been conducted using a three-dimensional, two-phase, wellbore and reservoir simulation model. Well tests from Cerro Prieto and the Hawaiian Geothermal project have been history matched. Using these well tests as a base, the influence of reservoir permeability, porosity, thickness, and heat capacity, along with flow rate and fracturing were studied. Single and two-phase transient well test equations were used to analyze these tests with poor results due to rapidly changing fluid properties and inability to calculate the flowing steam saturation in the reservoir. The injection of cold water into the reservoir does give good data from which formation properties can be calculated.

  18. Method and device for measuring single-shot transient signals

    DOEpatents

    Yin, Yan

    2004-05-18

    Methods, apparatus, and systems, including computer program products, implementing and using techniques for measuring multi-channel single-shot transient signals. A signal acquisition unit receives one or more single-shot pulses from a multi-channel source. An optical-fiber recirculating loop reproduces the one or more received single-shot optical pulses to form a first multi-channel pulse train for circulation in the recirculating loop, and a second multi-channel pulse train for display on a display device. The optical-fiber recirculating loop also optically amplifies the first circulating pulse train to compensate for signal losses and performs optical multi-channel noise filtration.

  19. Transient analysis of the 1991 Hijiori Shallow Reservoir Circulation Test

    SciTech Connect

    Hyodo, M.; Shinohara, N.; Takasugi, S.; Wright, C.A.; Conant, R..

    1996-01-24

    Like any dynamic system, HDR reservoirs cannot be fully characterized by their steady-state behavior. Circulation tests analysis should be performed on both the steady-state response and the transient response of HDR systems. Transient analysis allows not only estimation of critical reservoir parameters and how these parameters change with operating conditions / history, but transient analysis also aids in evaluating the feasibility of various modes of HDR system operation (base load, load following, etc.). This paper details the transient analysis of NEDO's FY 1991 Shallow Reservoir Circulation Test at the Hijiori HDR site in Japan. Reservoir fluid storage is carefully bounded through the employment of two distinct methods for calculation of the fluid storage from the observed transient response. A brief discussion is also included of the distribution of reservoir fluid storage; the relationship between pressure, reservoir stress, and apparent reservoir capacitance; and appropriate circulation test design to facilitate transient analysis.

  20. Transient Molecular Transfer During Vacuum Testing

    NASA Technical Reports Server (NTRS)

    Perry, Radford L.

    2011-01-01

    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

  1. Induced shock pulse testing by transient waveform control

    NASA Technical Reports Server (NTRS)

    Kim, B. K.

    1973-01-01

    A method of synthesizing an arbitrarily shaped transient time pulse on vibration exciters is described. The transient waveform control technique is based on recent developments in digital time series analysis, the real-time FFT processor. A brief description of the theory, error estimates and hardware/software implementation to the JPL Dynamic Environmental Testing Laboratory is presented.

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

    NASA Technical Reports Server (NTRS)

    Lachenmayr, Georg

    1992-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

    Vibbart, Charles M.

    1988-01-01

    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.

  4. See Change: Classifying single observation transients from HST using SNCosmo

    NASA Astrophysics Data System (ADS)

    Sofiatti Nunes, Caroline; Perlmutter, Saul; Nordin, Jakob; Rubin, David; Lidman, Chris; Deustua, Susana E.; Fruchter, Andrew S.; Aldering, Greg Scott; Brodwin, Mark; Cunha, Carlos E.; Eisenhardt, Peter R.; Gonzalez, Anthony H.; Jee, Myungkook J.; Hildebrandt, Hendrik; Hoekstra, Henk; Santos, Joana; Stanford, S. Adam; Stern, Dana R.; Fassbender, Rene; Richard, Johan; Rosati, Piero; Wechsler, Risa H.; Muzzin, Adam; Willis, Jon; Boehringer, Hans; Gladders, Michael; Goobar, Ariel; Amanullah, Rahman; Hook, Isobel; Huterer, Dragan; Huang, Jiasheng; Kim, Alex G.; Kowalski, Marek; Linder, Eric; Pain, Reynald; Saunders, Clare; Suzuki, Nao; Barbary, Kyle H.; Rykoff, Eli S.; Meyers, Joshua; Spadafora, Anthony L.; Hayden, Brian; Wilson, Gillian; Rozo, Eduardo; Hilton, Matt; Dixon, Samantha; Yen, Mike

    2016-01-01

    The Supernova Cosmology Project (SCP) is executing "See Change", a large HST program to look for possible variation in dark energy using supernovae at z>1. As part of the survey, we often must make time-critical follow-up decisions based on multicolor detection at a single epoch. We demonstrate the use of the SNCosmo software package to obtain simulated fluxes in the HST filters for type Ia and core-collapse supernovae at various redshifts. These simulations allow us to compare photometric data from HST with the distribution of the simulated SNe through methods such as Random Forest, a learning method for classification, and Gaussian Kernel Estimation. The results help us make informed decisions about triggered follow up using HST and ground based observatories to provide time-critical information needed about transients. Examples of this technique applied in the context of See Change are shown.

  5. Investigations on heavy ion induced Single-Event Transients (SETs) in highly-scaled FinFETs

    NASA Astrophysics Data System (ADS)

    Gaillardin, M.; Raine, M.; Paillet, P.; Adell, P. C.; Girard, S.; Duhamel, O.; Andrieu, F.; Barraud, S.; Faynot, O.

    2015-12-01

    We investigate Single-Event Transients (SET) in different designs of multiple-gate devices made of FinFETs with various geometries. Heavy ion experimental results are explained by using a thorough charge collection analysis of fast transients measured on dedicated test structures. Multi-level simulations are performed to get new insights into the charge collection mechanisms in multiple-gate devices. Implications for multiple-gate device design hardening are finally discussed.

  6. Alternatives Analysis for the Resumption of Transient Testing Program

    SciTech Connect

    Lee Nelson

    2013-11-01

    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

  7. Transient Positive Horizontal Head Impulse Test in Pregabalin Intoxication.

    PubMed

    Jeong, Seong-Hae; Kim, Yong Soo; Lee, Ju-Hoen; Jo, Hyunjin; Lee, Ae Young; Kim, Jae-Moon

    2015-12-01

    Head impulse test (HIT) is helpful to understanding high-frequency vestibulo-ocular reflex in patients with dizziness and imbalance. There are some reports on abnormal HITs in cerebellar disorder. To our knowledge, there was no report of transient bilateral positive head impulse related to antiepileptic drugs. A 65-year-old woman developed dizziness and imbalance after treatment with pregabalin for pain control of radiation cystitis. Neurological examination exhibited positive bilateral HIT results, in addition to ataxia and gaze-evoked rebound nystagmus. Pregabalin intoxication can evoke transient positive horizontal head impulse test as another indicator of cerebellar dysfunction. PMID:26819943

  8. Transient Positive Horizontal Head Impulse Test in Pregabalin Intoxication

    PubMed Central

    Jeong, Seong-Hae; Kim, Yong Soo; Lee, Ju-Hoen; Jo, Hyunjin; Lee, Ae Young; Kim, Jae-Moon

    2015-01-01

    Head impulse test (HIT) is helpful to understanding high-frequency vestibulo-ocular reflex in patients with dizziness and imbalance. There are some reports on abnormal HITs in cerebellar disorder. To our knowledge, there was no report of transient bilateral positive head impulse related to antiepileptic drugs. A 65-year-old woman developed dizziness and imbalance after treatment with pregabalin for pain control of radiation cystitis. Neurological examination exhibited positive bilateral HIT results, in addition to ataxia and gaze-evoked rebound nystagmus. Pregabalin intoxication can evoke transient positive horizontal head impulse test as another indicator of cerebellar dysfunction. PMID:26819943

  9. SINGLE FIBER TESTING VIA FAVIMAT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cotton fiber is usually tested in bulk form utilizing a mass or beard of fibers to be presented to a test instrument for measurement. There are many reasons for this, not the least of which is that handling single cotton fibers is tedious and time consuming. Cotton breeders are being pushed to mak...

  10. RELAP5 Prediction of Transient Tests in the RD-14 Test Facility

    SciTech Connect

    Lee, Sukho; Kim, Manwoong; Kim, Hho-Jung; Lee, John C.

    2005-09-15

    Although the RELAP5 computer code has been developed for best-estimate transient simulation of a pressurized water reactor and its associated systems, it could not assess the thermal-hydraulic behavior of a Canada deuterium uranium (CANDU) reactor adequately. However, some studies have been initiated to explore the applicability for simulating a large-break loss-of-coolant accident in CANDU reactors. In the present study, the small-reactor inlet header break test and the steam generator secondary-side depressurization test conducted in the RD-14 test facility were simulated with the RELAP5/MOD3.2.2 code to examine its extended capability for all the postulated transients and accidents in CANDU reactors. The results were compared with experimental data and those of the CATHENA code performed by Atomic Energy of Canada Limited.In the RELAP5 analyses, the heated sections in the facility were simulated as a multichannel with five pipe models, which have identical flow areas and hydraulic elevations, as well as a single-pipe model.The results of the small-reactor inlet header break and the steam generator secondary-side depressurization simulations predicted experimental data reasonably well. However, some discrepancies in the depressurization of the primary heat transport system after the header break and consequent time delay of the major phenomena were observed in the simulation of the small-reactor inlet header break test.

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

    NASA Astrophysics Data System (ADS)

    McDonald, Peter W.

    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.

  12. Parametric Thermal Models of the Transient Reactor Test Facility (TREAT)

    SciTech Connect

    Bradley K. Heath

    2014-03-01

    This work supports the restart of transient testing in the United States using the Department of Energy’s Transient Reactor Test Facility at the Idaho National Laboratory. It also supports the Global Threat Reduction Initiative by reducing proliferation risk of high enriched uranium fuel. The work involves the creation of a nuclear fuel assembly model using the fuel performance code known as BISON. The model simulates the thermal behavior of a nuclear fuel assembly during steady state and transient operational modes. Additional models of the same geometry but differing material properties are created to perform parametric studies. The results show that fuel and cladding thermal conductivity have the greatest effect on fuel temperature under the steady state operational mode. Fuel density and fuel specific heat have the greatest effect for transient operational model. When considering a new fuel type it is recommended to use materials that decrease the specific heat of the fuel and the thermal conductivity of the fuel’s cladding in order to deal with higher density fuels that accompany the LEU conversion process. Data on the latest operating conditions of TREAT need to be attained in order to validate BISON’s results. BISON’s models for TREAT (material models, boundary convection models) are modest and need additional work to ensure accuracy and confidence in results.

  13. SINGLE HEATER TEST FINAL REPORT

    SciTech Connect

    J.B. Cho

    1999-05-01

    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.

  14. Analysis of Transient Pressure Tests for Olkaria Exploration Wells

    SciTech Connect

    Haukwa, Charles B.

    1987-01-20

    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.

  15. Electromagnetic transients in substations. Volume 3, Test results: Final report

    SciTech Connect

    Wiggins, C.M.; Nickel, F.S.; Salas, T.M.; Thomas, D.E.

    1993-04-01

    High frequency transient electromagnetic interference (EMI) caused by faults, lightning, and switching on high voltage circuits in substations is characterized and quantified using a mobile four-channel transient EMI measurements system and validated traveling wave transient analysis models. More than 800 waveforms of high voltage switching transients and staged-faults were measured in air- and gas-insulated substations and used to validate a system of interrelated substation interference coupling models. The highest transient EMI levels expected from initial conditions of 2PU (Per Unit) disconnect switching, a 2PU circuit breaker fault, and a 10 kA lightning strike inside substations through 500 kV are calculated using the models. These initial conditions, believed to be nominally worst case for these three high voltage EMI sources, are defined as follows. For disconnect switching, the 2PU initial condition represents the maximum peak phase-to-ground voltage that can occur across a switch gap restriking at its greatest separation. An initial condition of 2PU peak phase-to-ground voltage can occur on an open and adjacent substation bus during switching from a remote location. A 10 kA lightning strike represents the maximum current expected to be attached directly to a 500 kV bus as a result of a shielding failure. Volume 1 of this report contains a summary and recommendations; volume 2 covers the computer models; volume 3 provides detailed results of the interference tests; and volumes 4 and 5, available on demand, contain data logs, raw data plots, and digital waveforms.

  16. Transient analysis of lossless single-phase nonuniform transmission lines

    SciTech Connect

    Oufi, E.A.; AlFuhaid, A.S.; Saied, M.M. . Electrical and Computer Engineering Dept.)

    1994-07-01

    A new method has been developed to study the transient behavior of nonuniform transmission lines whose parameters can have any arbitrary space variation. Using the exponential line as a building block, s-domain expressions are obtained for the voltage and current at any point along the nonuniform line. An efficient numerical Laplace-transform inversion technique is then used to compute the time-domain solution. Computer simulations and comparisons with other solution methods are included.

  17. 40 CFR 1039.510 - Which duty cycles do I use for transient testing?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ENGINES Test Procedures 1039.510 Which duty cycles do I use for transient testing? (a) Measure emissions... consists of an initial run through the transient duty cycle from a cold start, 20 minutes with no...

  18. Large transient fault current test of an electrical roll ring

    NASA Technical Reports Server (NTRS)

    Yenni, Edward J.; Birchenough, Arthur G.

    1992-01-01

    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.

  19. Large transient fault current test of an electrical roll ring

    NASA Astrophysics Data System (ADS)

    Yenni, Edward J.; Birchenough, Arthur G.

    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.

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

    NASA Technical Reports Server (NTRS)

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

    2003-01-01

    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.

  1. Modeling transient streaming potentials in falling-head permeameter tests.

    PubMed

    Malama, Bwalya; Revil, Andr

    2014-01-01

    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

  2. Transient rotor dynamic rub phenomena - Theory and test

    NASA Technical Reports Server (NTRS)

    Kascak, A. F.; Montaque, G.; Palazzolo, A. B.

    1987-01-01

    This paper develops an implicit integration scheme for transient rotor dynamic rub prediction and includes a correlation study with actual test results. A Nordsieck-like numerical integration scheme is applied directly to the second-order equations of motion. The assumption that forces and torques on the rotor are functions of the position and velocity at the point of application and its nearest neighbor is made in order to make the computational time proportional to the number of elements in the rotor dynamics model rather than the cube of the number. The test rig consists of a turbine driven, flexible shaft supported by squeeze film dampers. The blade loss event occurs due to collision of a balance bolt on one of the disks with a high speed plunger. The rotor is seen to spiral outward and contact against a stationary assemblage of seal shoes.

  3. Review of single transient oscillographic recorders with gigahertz bandwidth

    SciTech Connect

    Campbell, D.E.

    1982-10-20

    In laser driven inertial confinement fusion research, at Livermore, we are diagnosing many phenomena that occur in a time frame that exceeds the capabilities of even the most advanced, present day oscillographic recording instruments. Many of the by-products of the interaction between the laser beam and fuel pellet are monitored to determine the specifics of the fusion process. By the use of appropriate detectors, we convert the information contained in the radiated by-products to electrical signals which are recorded on high bandwidth oscillographic recorders. Our present range of recording capabilities for one x-ray diagnostic measurement in use at Livermore is shown. A commonly used configuration consists of an XRD-31 x-ray detector connected to a direct access Tektronix R7912 transient digitizer using 1/2 in. diameter air dielectric coaxial cable. This configuration gives a system fwhm of approximately 335 ps. Our premier configuration, on the other hand, consists of an improved response detector and a French Thomson-CSF TSN-660 oscilloscope with a shorter length of coaxial cable (typically 20 feet). The system fwhm in this case is less than 120 ps which is our fastest oscillographic recording system at the present time.

  4. Single Event Transients in Voltage Regulators for FPGA Power Supply Applications

    NASA Technical Reports Server (NTRS)

    Poivey, Christian; Sanders, Anthony; Kim, Hak; Phan, Anthony; Forney, Jim; LaBel, Kenneth A.; Karsh, Jeremy; Pursley, Scott; Kleyner, Igor; Katz, Richard

    2006-01-01

    As with other bipolar analog devices, voltage regulators are known to be sensitive to single event transients (SET). In typical applications, large output capacitors are used to provide noise immunity. Therefore, since SET amplitude and duration are generally small, they are often of secondary importance due to this capacitance filtering. In low voltage applications, however, even small SET are a concern. Over-voltages may cause destructive conditions. Under-voltages may cause functional interrupts and may also trigger electrical latchup conditions. In addition, 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. In the case of FPGA power supplies applications, SETS are critical. For example, in the case of Actel FPGA RTAX family, core power supply voltage is 1.5V. Manufacturer specifies an absolute maximum rating of 1.6V and recommended operating conditions between 1.425V and 1.575V. Therefore, according to the manufacturer, any transient of amplitude greater than 75 mV can disrupt normal circuit functions, and overvoltages greater than 100 mV may damage the FPGA. We tested five low dropout voltage regulators for SET sensitivity under a large range of circuit application conditions.

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

    SciTech Connect

    El-Genk, M.S.; Xue, H. . Inst. for Space Nuclear Power Studies)

    1994-10-01

    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.

  6. Transient Analysis Used to Study Thermal Radiation Effects in Single and Composite Semitransparent Layers

    NASA Technical Reports Server (NTRS)

    1996-01-01

    In a continuing in-house program at the NASA Lewis Research Center, analytical and numerical methods are being developed to apply radiative analysis to predict transient temperature distributions and heat flows in partially transmitting materials. Results have been obtained for a single plane layer, and a transient analysis is being developed for a two-layer composite where each layer has a different refractive index. Because the ceramic refractive indices are larger than one, internal reflections are produced at the surfaces and at the internal interface. Reflections tend to distribute energy within a layer, and this affects the transient temperature distributions.

  7. Transient Testing of Nuclear Fuels and Materials in United States

    SciTech Connect

    Daniel M. Wachs

    2012-12-01

    The US Department of Energy (DOE) has been engaged in an effort to develop and qualify next generation LWR fuel with enhanced performance and safety and reduced waste generation since 2010. This program, which has emphasized collaboration between the DOE, U.S. national laboratories and nuclear industry, was refocused from enhanced performance to enhanced accident tolerance following the events at Fukushima in 2011. Accident tolerant fuels have been specifically described as fuels that, in comparison with standard UO2-Zircaloy, can tolerate loss of active cooling in the reactor core for a considerably longer time period (depending on the LWR system and accident scenario) while maintaining or improving the fuel performance during normal operations, operational transients, as well as design-basis and beyond design-basis events. The program maintains an ambitious goal to insert a lead test assembly (LTA) of the new design into a commercial power reactor by 2022 .

  8. Transient Liquid Phase Bonding Single-Crystal Superalloys with Orientation Deviations: Creep Properties

    NASA Astrophysics Data System (ADS)

    Sheng, Naicheng; Liu, Jide; Jin, Tao; Sun, Xiaofeng; Hu, Zhuangqi

    2015-12-01

    Superalloys single crystals with various orientation deviations were bonded using transient liquid phase bonding method, then the creep properties of the bonded specimens were tested at 1033 K (760 °C)/780 MPa. It is found that the creep life of the bonded specimens decreases with the increase of the relative orientation deviations. Despite the fracture of the specimens appears on the bonding region, the deformation mechanism changes from specimens with low angle boundary to high angle boundary. In low angle boundary specimens, cleavage originated from the defects grows perpendicularly to the tensile stress and connects through the different slip planes around the cleavage planes. In this case, the deformation proceeds by the dislocations and stacking faults on multi-planes. With increasing orientation deviation, dislocation and stacking faults moved on single plane. As a result, the dislocations interact with the grain boundary and lead to fracture. Based on the present investigation, the orientation of the bonded superalloys single crystal should be controlled so that the introduced grain boundaries are relatively small and exhibit higher creep strength.

  9. Irisin in Blood Increases Transiently after Single Sessions of Intense Endurance Exercise and Heavy Strength Training

    PubMed Central

    Nygaard, Håvard; Slettaløkken, Gunnar; Vegge, Geir; Hollan, Ivana; Whist, Jon Elling; Strand, Tor; Rønnestad, Bent R.; Ellefsen, Stian

    2015-01-01

    Purpose Irisin is a recently identified exercise-induced hormone that increases energy expenditure, at least in rodents. The main purpose of this study was to test the hypothesis that Irisin increases acutely in blood after singular sessions of intense endurance exercise (END) and heavy strength training (STR). Secondary, we wanted to explore the relationship between body composition and exercise-induced effects on irisin, and the effect of END and STR on muscular expression of the irisin gene FNDC5. Methods Nine moderately trained healthy subjects performed three test days using a randomized and standardized crossover design: one day with 60 minutes of END, one day with 60 minutes of STR, and one day without exercise (CON). Venous blood was sampled over a period of 24h on the exercise days. Results Both END and STR led to transient increases in irisin concentrations in blood, peaking immediately after END and one hour after STR, before gradually returning to baseline. Irisin responses to STR, but not END, showed a consistently strong negative correlation with proportions of lean body mass. Neither END nor STR affected expression of FNDC5, measured 4h after training sessions, though both protocols led to pronounced increases in PGC-1α expression, which is involved in transcriptional control of FNDC5. Conclusion The results strongly suggest that single sessions of intense endurance exercise and heavy strength training lead to transient increases in irisin concentrations in blood. This was not accompanied by increased FNDC5 expression, measured 4h post-exercise. The results suggest that irisin responses to resistance exercise are higher in individuals with lower proportions of lean body mass. PMID:25781950

  10. Transient productivity index for numerical well test simulations

    SciTech Connect

    Blanc, G.; Ding, D.Y.; Ene, A.

    1997-08-01

    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.

  11. Laser-induced transient stress distribution inside a single crystal by time-resolved birefringence imaging

    NASA Astrophysics Data System (ADS)

    Tochio, Takaya; Sakakura, Masaaki; Kanehira, Shingo; Shimotsuma, Yasuhiko; Miura, Kiyotaka; Hirao, Kazuyuki

    2012-03-01

    When femtosecond laser pulses are focused inside a single crystal, anisotropic structural changes such as dislocation and cleavage occur along specific orientations. It can be interpreted that the anisotropic structural changes should be induced by transient stress after photoexcitation, such as a thermal stress and stress wave. To elucidate the mechanism of the laser induced structural changes inside crystals, we developed a novel time-resolved polarization imaging system, in which circularly polarized laser pulse was used as a probe light. The system enabled us to observe laser-induced transient stress distribution as well as the orientation after focusing fs laser pulses inside MgO and LiF single crystals. Based on the observation, we elucidated the relation between laser-induced transient stress distribution and anisotropic structural change inside the crystals.

  12. Barometric pressure transient testing applications at the Nevada Test Site: formation permeability analysis. Final report

    SciTech Connect

    Hanson, J.M.

    1984-12-01

    The report evaluates previous investigations of the gas permeability of the rock surrounding emplacement holes at the Nevada Test Site. The discussion sets the framework from which the present uncertainty in gas permeability can be overcome. The usefulness of the barometric pressure testing method has been established. Flow models were used to evaluate barometric pressure transients taken at NTS holes U2fe, U19ac and U20ai. 31 refs., 103 figs., 18 tabs. (ACR)

  13. Revisiting single photon avalanche diode current-voltage modeling and transient characteristics

    SciTech Connect

    Javitt, M.; Savuskan, V. Merhav, T.; Nemirovsky, Y.

    2014-05-28

    A model for the current-voltage and transient behavior of Single Photon Avalanche Diodes (SPADs) based on device physics is presented. The results of the model are compared to actual measurements and a reasonable fit is seen. Additionally, the model provides a useful tool for designing quenching circuitry and determining optimal operation conditions of the SPAD.

  14. 40 CFR 1039.510 - Which duty cycles do I use for transient testing?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CFR 1065.514 to confirm that the test is valid. ... ENGINES Test Procedures 1039.510 Which duty cycles do I use for transient testing? (a) Measure emissions... consists of an initial run through the transient duty cycle from a cold start, 20 minutes with no...

  15. 40 CFR 1039.510 - Which duty cycles do I use for transient testing?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CFR 1065.514 to confirm that the test is valid. ... ENGINES Test Procedures 1039.510 Which duty cycles do I use for transient testing? (a) Measure emissions... consists of an initial run through the transient duty cycle from a cold start, 20 minutes with no...

  16. 40 CFR 1039.510 - Which duty cycles do I use for transient testing?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... established criteria as specified in 40 CFR 1065.514 to confirm that the test is valid. ... ENGINES Test Procedures 1039.510 Which duty cycles do I use for transient testing? (a) Measure emissions... consists of an initial run through the transient duty cycle from a cold start, 20 minutes with no...

  17. 40 CFR 1039.510 - Which duty cycles do I use for transient testing?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ENGINES Test Procedures 1039.510 Which duty cycles do I use for transient testing? (a) Measure emissions... consists of an initial run through the transient duty cycle from a cold start, 20 minutes with no engine... established criteria as specified in 40 CFR 1065.514 to confirm that the test is valid....

  18. Prodiag : a process-independent transient diagnostic system - II : validation tests.

    SciTech Connect

    Reifman, J.; Wei, T. Y. C.

    1999-01-01

    The unique capabilities of the first-principles-based PRODIAG diagnostic system to identify unanticipated process component faults and to be ported across different processes/plants through modification of only input data files are demonstrated in two validation tests. The Braidwood Nuclear Power Plant full-scope operator training simulator is used to generate transient data for two plant systems used in the validation tests. The first test consists of a blind test performed with 39 simulated transients of 20 distinct types in the Braidwood chemical and volume control system. Of the 39 transients, 37 are correctly identified with varying precision within the first 40 s into the transient while the remaining two transients are not identified. The second validation test consists of a double-blind test performed with 14 simulated transients in the Braidwood component coolant water system. In addition to having no prior knowledge of the identity of the transients, in the double-blind test we also had no prior information regarding the identity of the component faults that the simulator was capable of modeling. All 14 transient events are correctly identified with varying precision within the first 30 s into the transient. The test results provide enough evidence to successfully confirm the unique capabilities of the plant-level PRODIAG diagnostic system.

  19. PRODIAG: A process-independent transient diagnostic system. 2: Validation tests

    SciTech Connect

    Reifman, J.; Wei, T.Y.C.

    1999-03-01

    The unique capabilities of the first-principles-based PRODIAG diagnostic system to identify unanticipated process component faults and to be ported across different processes/plants through modification of only input data files are demonstrated in two validation tests. The Braidwood Nuclear Power Plant full-scope operator training simulator is used to generate transient data for two plant systems used in the validation tests. The first test consists of a blind test performed with 39 simulated transients of 20 distinct types in the Braidwood chemical and volume control system. Of the 39 transients, 37 are correctly identified with varying precision within the first 40 s into the transient while the remaining two transients are not identified. The second validation test consists of a double-blind test performed with 14 simulated transients in the Braidwood component coolant water system. In addition to having no prior knowledge of the identity of the transients, in the double-blind test they also had no prior information regarding the identity of the component faults that the simulator was capable of modeling. All 14 transient events are correctly identified with varying precision within the first 30 s into the transient. The test results provide enough evidence to successfully confirm the unique capabilities of the plant-level PRODIAG diagnostic system.

  20. An analog cell to detect single event transients in voltage references

    NASA Astrophysics Data System (ADS)

    Franco, F. J.; Palomar, C.; Izquierdo, J. G.; Agapito, J. A.

    2015-01-01

    A reliable voltage reference is mandatory in mixed-signal systems. However, this family of components can undergo very long single event transients when operating in radiation environments such as space and nuclear facilities due to the impact of heavy ions. The purpose of the present paper is to demonstrate how a simple cell can be used to detect these transients. The cell was implemented with typical COTS components and its behavior was verified by SPICE simulations and in a laser facility. Different applications of the cell are explored as well.

  1. Successful transient expression of Cas9 and single guide RNA genes in Chlamydomonas reinhardtii.

    PubMed

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

    2014-11-01

    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

  2. 40 CFR Appendix E to Subpart S of... - Transient Test Driving Cycle

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 2 2011-07-01 2011-07-01 false Transient Test Driving Cycle E Appendix... Driving Cycle (I) Driver's trace. All excursions in the transient driving cycle shall be evaluated by the... determine a valid test. (II) Driving cycle. The following table shows the time speed relationship for...

  3. 40 CFR Appendix E to Subpart S of... - Transient Test Driving Cycle

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 2 2013-07-01 2013-07-01 false Transient Test Driving Cycle E Appendix... Driving Cycle (I) Driver's trace. All excursions in the transient driving cycle shall be evaluated by the... determine a valid test. (II) Driving cycle. The following table shows the time speed relationship for...

  4. Calcium transients in subcompartments of the leech Retzius neuron as induced by single action potentials.

    PubMed

    Beck, A; Lohr, C; Deitmer, J W

    2001-07-01

    Regional Ca(2+) influx into neurons plays an essential role for fast signal processing, yet it is little understood. We have investigated intracellular Ca(2+) transients induced by a single action potential (AP) in Retzius neurons in situ of isolated ganglia of the leech Hirudo medicinalis using confocal laser scanning microscopy in the cell body, in different axonal branches, and in dendrites. In the cell body, a single AP induced a Ca(2+) transient in submembrane regions, while in central regions no fluorescence change was detected. Burst activity evoked a much larger Ca(2+) influx, which elicited Ca(2+) signals in central somatic regions, including the cell nucleus. A single AP induced a Ca(2+) transient in distal branches of the axon and in dendrites that was significantly larger than in the proximal axon and in the cell body (p <.05), and the recovery of the Ca(2+) transient was significantly faster in axonal branches than in dendrites (p <.01). The AP-induced Ca(2+) transient was inhibited by Co(2+) (2 mM). The P/Q-type Ca(2+) channel blocker omega-agatoxin TK (500 nM) and the L-type Ca(2+) channel blocker nifedipine (20 microM) had no effect on the Ca(2+) transient, whereas the L-type Ca(2+) channel blocker methoxyverapamil (D600, 0.5-1 mM) irreversibly reduced the Ca(2+) transient by 37% in axons and by 42% in dendrites. Depletion of intracellular Ca(2+) stores following inhibition of endoplasmic Ca(2+)-ATPases by cyclopiazonic acid (10 microM) decreased the AP-induced Ca(2+) transient in the dendrites by 21% (p <.01), but not in axons, and increased the Ca(2+) recovery time constant (tau) in the axonal branches by 129% (p <.01), but not in dendrites. The results indicate that an AP evokes a voltage-gated Ca(2+) influx into all subcompartments of the Retzius neuron, where it produces a Ca(2+) signal of different size and/or kinetics. This may contribute to the modulation of electrical excitation and propagation of APs, and to different modes of synaptic and nonsynaptic processes. PMID:11391646

  5. Transient thermal dissipation method for xylem sap flow measurement: implementation with a single probe.

    PubMed

    Do, F C; Isarangkool Na Ayutthaya, S; Rocheteau, A

    2011-04-01

    Comparisons of tree water relations between treatments, species and sites are facilitated by the use of simple and low-cost measurements of xylem sap flow rates. The transient thermal dissipation (TTD) method is a variant of the constant thermal dissipation (CTD) method of Granier. It has the advantages of limiting thermal interference and of saving electrical energy. Here, our concern was to test a new step towards simplicity and low cost: the applicability of the TTD method with a single probe, i.e., without a reference sensor, following a cycle of 10 min heating and 10 min cooling, and using the same thermal index and multi-species calibration previously assessed with a dual probe. First, the responses of the dual and single probes were compared in an artificial hydraulic column of sawdust in the laboratory over a complete range of flux densities, from 0.3 to 4.0 l dm? h?. Second, diurnal kinetics were compared in a young tree with rapid changes in the sapwood reference temperature of up to 5 C h? for 5 consecutive days. With a relatively stable reference temperature, laboratory results showed that a single probe yielded the same temperature signal and thermal index as a dual probe for the full range of sap flux densities. Within the tree, the cooled temperature of the heated probe, linearly interpolated, proved to be an accurate indicator of the change in the reference temperature over time. Logically, the temperature signals and estimates of sap flux density with the single probe did not differ from the dual-sensor measurements when the cooled temperature was interpolated. Additionally, the responses of the thermal index, yielded in the hydraulic experiment with the sawdust column, fell within the variability of the multi-species calibration. This result supports the previous assessment of a non-species-specific calibration for the TTD method with diffuse porous media. In conclusion, our results showed that the TTD method can be directly applied with a single probe. Limitations and possible future progress are pointed out. This measurement system is probably the simplest technique currently available to measure xylem sap flow. PMID:21498407

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

    NASA Technical Reports Server (NTRS)

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

    2006-01-01

    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

  7. Preliminary Analysis of the Transient Reactor Test Facility (TREAT) with PROTEUS

    SciTech Connect

    Connaway, H. M.; Lee, C. H.

    2015-11-30

    The neutron transport code PROTEUS has been used to perform preliminary simulations of the Transient Reactor Test Facility (TREAT). TREAT is an experimental reactor designed for the testing of nuclear fuels and other materials under transient conditions. It operated from 1959 to 1994, when it was placed on non-operational standby. The restart of TREAT to support the U.S. Department of Energy’s resumption of transient testing is currently underway. Both single assembly and assembly-homogenized full core models have been evaluated. Simulations were performed using a historic set of WIMS-ANL-generated cross-sections as well as a new set of Serpent-generated cross-sections. To support this work, further analyses were also performed using additional codes in order to investigate particular aspects of TREAT modeling. DIF3D and the Monte-Carlo codes MCNP and Serpent were utilized in these studies. MCNP and Serpent were used to evaluate the effect of geometry homogenization on the simulation results and to support code-to-code comparisons. New meshes for the PROTEUS simulations were created using the CUBIT toolkit, with additional meshes generated via conversion of selected DIF3D models to support code-to-code verifications. All current analyses have focused on code-to-code verifications, with additional verification and validation studies planned. The analysis of TREAT with PROTEUS-SN is an ongoing project. This report documents the studies that have been performed thus far, and highlights key challenges to address in future work.

  8. Creation of a transient vapor nanogap between two fluidic reservoirs for single molecule manipulation

    NASA Astrophysics Data System (ADS)

    Polonsky, Stanislav; Balagurusamy, Venkat S. K.; Ott, John A.

    2014-08-01

    We introduce a new experimental technique for manipulating a segment of a charged macromolecule inside a transient nanogap between two fluidic reservoirs. This technique uses an FPGA-driven nanopositioner to control the coupling of a nanopipette with the liquid surface of a fluidic cell. We present results on creating a transient nanogap, triggered by a translocation of double-stranded DNA between a nanopipette and a fluidic cell, and measure the probability to find the molecule near the tip of the nanopipette after closing the gap. The developed platform will enable testing of our recent theoretical predictions for the behavior of charged macromolecule in a nanogap between two fluidic reservoirs.

  9. A 10 GHz bandwidth, single transient, digitized oscilloscope with 20 GHz capability

    SciTech Connect

    Hudson, C.L.; Kocimski, S.M.; Spector, J.; Thomas, J.B.; Woodstra, R.R.

    1993-12-31

    EG&G/EM has developed an oscilloscope with a {minus}3 dB bandwidth greater than 10 GHz. Its rolloff characteristics are such that single-transient data greater than 20 GHz may be captured. A demountable CCD camera records the oscilloscope trace and is provided with PC-compatible capture and data processing software. The capabilities of the oscilloscope, camera, and its processing software are described and examples of the system`s performance is shown.

  10. Transient dynamics in magnetic force microscopy for a single-spin measurement

    SciTech Connect

    Berman, G.P.; Borgonovi, F.; Lopez, G.V.; Tsifrinovich, V.I.

    2003-07-01

    We analyze a single-spin measurement using a transient process in magnetic force microscopy which could increase the maximum operating temperature by a factor of Q (the quality factor of the cantilever) in comparison with the static Stern-Gerlach effect. We obtain an exact solution of the master equation, which confirms this result. We also discuss the conditions required to create a macroscopic quantum superposition in the cantilever.

  11. 40 CFR Appendix E to Subpart S of... - Transient Test Driving Cycle

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... E to Subpart S of Part 51 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR.../Maintenance Program Requirements Pt. 51, Subpt. S, App. E Appendix E to Subpart S of Part 51—Transient Test Driving Cycle (I) Driver's trace. All excursions in the transient driving cycle shall be evaluated by...

  12. Experimental capabilities of the transient reactor test (TREAT) facility.

    SciTech Connect

    Crawford, D. C.

    1998-07-28

    The TREAT facility was designed and built in the 1950s to provide a transient reactor for conducting safety experiments on reactor fuels. Throughout its almost 40-year history, it has proven to be a safe, reliable, and versatile facility, compiling a distinguished record of successful experiments. Several major improvements to the facility have been made, including an expansion of the building and of equipment handling capability, and enlargement of the access hole above the core, rearrangement of the reactor's control rods to provide more-uniform flux profiles, installation of improved reactor computer-control systems, a feedback system that safely allows real-time changes in power transients depending upon events occurring in the experiment, and several upgrades in the fast neutron hodoscope for improved experiment-fuel-motion diagnostics. The original TREAT fuel is still in use, however, since it appears to have no degradation from its many years of service.

  13. Transient currents of a single molecular junction with a vibrational mode

    NASA Astrophysics Data System (ADS)

    Ding, Guo-Hui; Xiong, Bo; Dong, Bing

    2016-02-01

    By using a propagation scheme for current matrices and an auxiliary mode expansion method, we investigate the transient dynamics of a single molecular junction coupled with a vibrational mode. Our approach is based on the spinless AndersonHolstein model and the dressed tunnelling approximation for the electronic self-energy in the polaronic regime. The time-dependent currents after a sudden switching on the tunnelling to leads, an abrupt upward step bias pulse and a step potential on the quantum dot are calculated. We show that the strong electronphonon interaction greatly influences the nonlinear response properties of the system, and gives rise to interesting characteristics on the time traces of transient currents.

  14. Computer simulation and experimental study of transient processes in a single-phase voltage transformer

    NASA Astrophysics Data System (ADS)

    Kruzhaev, A. V.; Elagin, I. A.; Pavleino, M. A.; Dmitriev, V. A.; Chaly, A. M.

    2015-02-01

    We perform simulation and experimental investigation of transient processes emerging in a single-phase transformer when it is connected to the network. The transformer model constructed taking into account the saturation of the steel of the core differs from standard models in detailed accounting for the magnetic flux leakage, which is required, for example, for a correct description of inrush current. Universality of the model for the type of transformers under study is ensured by the allowance for eddy current losses and calculation of the magnetic hysteresis in the steel core. The latter makes it possible to estimate the effect of residual magnetization of the core on the form of a transient process, which is studied in detail. The methods for computing model parameters are described and its experimental verification is carried out.

  15. Dissolution chemistry and biocompatibility of single-crystalline silicon nanomembranes and associated materials for transient electronics.

    PubMed

    Hwang, Suk-Won; Park, Gayoung; Edwards, Chris; Corbin, Elise A; Kang, Seung-Kyun; Cheng, Huanyu; Song, Jun-Kyul; Kim, Jae-Hwan; Yu, Sooyoun; Ng, Joanne; Lee, Jung Eun; Kim, Jiyoung; Yee, Cassian; Bhaduri, Basanta; Su, Yewang; Omennetto, Fiorenzo G; Huang, Yonggang; Bashir, Rashid; Goddard, Lynford; Popescu, Gabriel; Lee, Kyung-Mi; Rogers, John A

    2014-06-24

    Single-crystalline silicon nanomembranes (Si NMs) represent a critically important class of material for high-performance forms of electronics that are capable of complete, controlled dissolution when immersed in water and/or biofluids, sometimes referred to as a type of "transient" electronics. The results reported here include the kinetics of hydrolysis of Si NMs in biofluids and various aqueous solutions through a range of relevant pH values, ionic concentrations and temperatures, and dependence on dopant types and concentrations. In vitro and in vivo investigations of Si NMs and other transient electronic materials demonstrate biocompatibility and bioresorption, thereby suggesting potential for envisioned applications in active, biodegradable electronic implants. PMID:24684516

  16. Transient currents of a single molecular junction with a vibrational mode.

    PubMed

    Ding, Guo-Hui; Xiong, Bo; Dong, Bing

    2016-02-17

    By using a propagation scheme for current matrices and an auxiliary mode expansion method, we investigate the transient dynamics of a single molecular junction coupled with a vibrational mode. Our approach is based on the spinless Anderson-Holstein model and the dressed tunnelling approximation for the electronic self-energy in the polaronic regime. The time-dependent currents after a sudden switching on the tunnelling to leads, an abrupt upward step bias pulse and a step potential on the quantum dot are calculated. We show that the strong electron-phonon interaction greatly influences the nonlinear response properties of the system, and gives rise to interesting characteristics on the time traces of transient currents. PMID:26795556

  17. Comparison of Single-Event Transients Induced in an Operational Amplifier (LM124) by Pulsed Laser Light and a Broad Beam of Heavy Ions

    NASA Technical Reports Server (NTRS)

    Buchner, Steve; McMorrow, Dale; Poivey, Christian; Howard, James, Jr.; Pease, Rom; Savage, Mark; Boulghassoul, Younis; Massengill, Lloyd

    2003-01-01

    A comparison of transients from heavy-ion and pulsed-laser testing shows good agreement for many different voltage configurations. The agreement is illustrated by comparing directly individual transients and plots of transient amplitude versus width.

  18. Mechanism of single-event transient pulse quenching between dummy gate isolated logic nodes

    NASA Astrophysics Data System (ADS)

    Chen, Jian-Jun; Chi, Ya-Qing; Liang, Bin

    2015-01-01

    As integrated circuits scale down in size, a single high-energy ion strike often affects multiple adjacent logic nodes. The so-called single-event transient (SET) pulse quenching induced by single-event charge sharing collection has been widely studied. In this paper, SET pulse quenching enhancement is found in dummy gate isolated adjacent logic nodes compared with that isolated by the common shallow trench isolation (STI). The physical mechanism is studied in depth and this isolation technique is explored for SET mitigation in combinational standard cells. Three-dimensional (3D) technology computer-aided design simulation (TCAD) results show that this technique can achieve efficient SET mitigation. Project supported by the National Natural Science Foundation of China (Grant No. 61376109) and the Opening Project of National Key Laboratory of Science and Technology on Reliability Physics and Application Technology of Electrical Component, China (Grant No. ZHD201202).

  19. Single Event Effect (SEE) Test Planning 101

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

    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.

  20. 40 CFR 86.1333 - Transient test cycle generation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... The generation of the maximum torque curve is described in 40 CFR part 1065. (b) Example of the...: ER28AP14.006 Where: Max Test Speed = the maximum test speed as calculated in 40 CFR part 1065. (ii) For Otto-cycle engines: ER28AP14.007 Where: Max Test Speed = the maximum test speed as calculated in 40...

  1. Combined single channel and single molecule detection identifies subunit composition of STIM1-activated transient receptor potential canonical (TRPC) channels.

    PubMed

    Asanov, Alexander; Sampieri, Alicia; Moreno, Claudia; Pacheco, Jonathan; Salgado, Alfonso; Sherry, Ryan; Vaca, Luis

    2015-01-01

    Depletion of intracellular calcium ion stores initiates a rapid cascade of events culminating with the activation of the so-called Store-Operated Channels (SOC) at the plasma membrane. Calcium influx via SOC is essential in the initiation of calcium-dependent intracellular signaling and for the refilling of internal calcium stores, ensuring the regeneration of the signaling cascade. In spite of the significance of this evolutionary conserved mechanism, the molecular identity of SOC has been the center of a heated controversy spanning over the last 20 years. Initial studies positioned some members of the transient receptor potential canonical (TRPC) channel superfamily of channels (with the more robust evidence pointing to TRPC1) as a putative SOC. Recent evidence indicates that Stromal Interacting Molecule 1 (STIM1) activates some members from the TRPC family of channels. However, the exact subunit composition of TRPC channels remains undetermined to this date. To identify the subunit composition of STIM1-activated TRPC channels, we developed novel method, which combines single channel electrophysiological measurements based on the patch clamp technique with single molecule fluorescence imaging. We termed this method Single ion Channel Single Molecule Detection technique (SC-SMD). Using SC-SMD method, we have obtained direct evidence of the subunit composition of TRPC channels activated by STIM1. Furthermore, our electrophysiological-imaging SC-SMD method provides evidence at the molecular level of the mechanism by which STIM1 and calmodulin antagonize to modulate TRPC channel activity. PMID:25465892

  2. X-33 Injector Ignition Single Cell Test

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The X-33 injector ignition single cell was tested at the Marshall Space Flight Center test stand 116. The X-33 was a sub-scale technology demonstrator prototype of a Reusable Launch Vehicle (RLV) manufactured and named by Lockheed Martin as the Venture Star. The goal of the program was to demonstrate the technologies needed for a full size, single-stage-to-orbit RLV, thus enabling private industry to build and operate the RLV in the first decade of the 21st century. The X-33 program was cancelled in 2001.

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

    NASA Astrophysics Data System (ADS)

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

    2013-08-01

    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.

  4. Final Report for TREAT Transient Overpower Tests R9 and R12 -- Part 1

    SciTech Connect

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

    1980-04-01

    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.

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

    SciTech Connect

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

    1980-04-01

    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.

  6. Transient overvoltages and overcurrents on 12. 47 kV distribution lines; Field test results

    SciTech Connect

    Kolcio, N.; Halladay, J.A.; Allen, G.D.; Fromholtz, E.N. )

    1992-07-01

    The paper reports on field tests conducted by American Electric Power (AEP) on a 12.47 kV distribution line. The results cover capacitor switching and load dropping tests. The highest overvoltage recorded of 2.43 p.u. was during capacitor switching with arresters disconnected. At the line end, a maximum of 2.16 p.u. was measured during the line reenergization with the capacitor bank disconnected. The results give both overvoltage and overcurrent transient waveshape, magnitude and dominant frequency. Spectrum analysis of selected test shots provide the information on the extent of transient nonlinearity. Also, information is given on the field test instrumentation setup.

  7. Total Dose Effects on Single Event Transients in Digital CMOS and Linear Bipolar Circuits

    NASA Technical Reports Server (NTRS)

    Buchner, S.; McMorrow, D.; Sibley, M.; Eaton, P.; Mavis, D.; Dusseau, L.; Roche, N. J-H.; Bernard, M.

    2009-01-01

    This presentation discusses the effects of ionizing radiation on single event transients (SETs) in circuits. The exposure of integrated circuits to ionizing radiation changes electrical parameters. The total ionizing dose effect is observed in both complementary metal-oxide-semiconductor (CMOS) and bipolar circuits. In bipolar circuits, transistors exhibit grain degradation, while in CMOS circuits, transistors exhibit threshold voltage shifts. Changes in electrical parameters can cause changes in single event upset(SEU)/SET rates. Depending on the effect, the rates may increase or decrease. Therefore, measures taken for SEU/SET mitigation might work at the beginning of a mission but not at the end following TID exposure. The effect of TID on SET rates should be considered if SETs cannot be tolerated.

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

    NASA Technical Reports Server (NTRS)

    Mansur, M. Hossein; Schroeder, Jeffery A.

    1988-01-01

    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.

  9. 40 CFR 86.1333-2010 - Transient test cycle generation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CFR part 1065. (2) Torque is normalized to the maximum torque at the rpm listed with it. Therefore, to.... The generation of the maximum torque curve is described in 40 CFR part 1065. (b) Example of the... engines: ER13JY05.001 Where: MaxTestSpeed = the maximum test speed as calculated in 40 CFR part 1065....

  10. 40 CFR 86.1333-2010 - Transient test cycle generation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CFR part 1065. (2) Torque is normalized to the maximum torque at the rpm listed with it. Therefore, to.... The generation of the maximum torque curve is described in 40 CFR part 1065. (b) Example of the... engines: ER13JY05.001 Where: MaxTestSpeed = the maximum test speed as calculated in 40 CFR part 1065....

  11. 40 CFR 86.1333-2010 - Transient test cycle generation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CFR part 1065. (2) Torque is normalized to the maximum torque at the rpm listed with it. Therefore, to.... The generation of the maximum torque curve is described in 40 CFR part 1065. (b) Example of the... engines: ER13JY05.001 Where: MaxTestSpeed = the maximum test speed as calculated in 40 CFR part 1065....

  12. 40 CFR 86.1333-2010 - Transient test cycle generation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CFR part 1065. (2) Torque is normalized to the maximum torque at the rpm listed with it. Therefore, to.... The generation of the maximum torque curve is described in 40 CFR part 1065. (b) Example of the... engines: ER13JY05.001 Where: MaxTestSpeed = the maximum test speed as calculated in 40 CFR part 1065....

  13. SINGLE LABORATORY EVALUATION OF PHYTOTOXICITY TEST

    EPA Science Inventory

    The phytotoxicity method is a screening test used to predict the potential impact of chemicals on seed germination and early seedling growth. An evaluation of the procedure was conducted in order to establish the data quality that could be achieved within a single laboratory and ...

  14. A chassis test procedure to mimic the heavy-duty engine transient emissions certification test.

    PubMed

    Clark, N N; McKain, D L

    2001-03-01

    In-use emissions from vehicles using heavy-duty diesel engines can be significantly higher than the levels obtained during engine certification. These higher levels may be caused by a combination of degradation of engine components, poor engine maintenance, degradation or failure of emissions after-treatment devices, and engine and emissions system tampering. A direct comparison of in-use vehicle emissions with engine certification levels, however, is not possible without removing an engine from the vehicle in order to perform engine dynamometer emissions testing. The goal of this research was to develop a chassis test procedure that mimics the engine performance, and as such the expected emissions levels, from the engine certification emissions test prescribed in the U.S. Code of Federal Regulations. Emissions measurements were taken from two engines during testing on an engine dynamometer using the transient heavy-duty Federal Test Procedure (FTP). Additionally, each engine was installed in an appropriate vehicle, and emissions measurements were taken using a chassis dynamometer while employing a vehicle driving schedule intended to match closely the instantaneous torque and speed schedule of the engine FTP. Engine and chassis testing was performed with the engines in stock (unmodified) condition as well as in several modes to simulate either tampered or poorly maintained conditions. The use of a chassis test as a predictive tool for determining whether an engine in a vehicle would pass the engine certification test has proven to be worthwhile. Analysis of the data shows that identification of chassis-mounted engines with NOx emissions above certification levels is possible by employing engine-specific correction factors. In the case of PM emissions, significant data scatter allowed only the identification of gross PM emitters. Engine tampering and poor maintenance can raise PM and NOx emissions, and these increases can be correctly identified by a chassis test. Analysis of chassis and engine CO and HC emissions did not reveal a strong enough correlation to warrant the use of the chassis test for emissions screening of these two pollutants. PMID:11266106

  15. 40 CFR 86.1333-90 - Transient test cycle generation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... test. The torque and rpm feedback signals may be filtered. (d) Idle Speed Enhancement Devices (e.g... feedback torque equal to zero (using, for example, clutch disengagement, speed to torque control switching... longer, the average feedback torque must be within ±10 ft-lbs of zero. To allow for transition, up to...

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

    NASA Technical Reports Server (NTRS)

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

    2006-01-01

    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.

  17. NEXT Single String Integration Test Results

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

    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.

  18. Vibrational response of free standing single copper nanowire through transient reflectivity microscopy

    NASA Astrophysics Data System (ADS)

    Belliard, Laurent; Cornelius, Thomas W.; Perrin, Bernard; Kacemi, Nazim; Becerra, Loc; Thomas, Olivier; Eugenia Toimil-Molares, Maria; Cassinelli, Marco

    2013-11-01

    We report on the ultrafast vibrational response of single copper nanowires investigated by femtosecond transient reflectivity measurements. The oscillations of the sample reflectivity are correlated with individual modes of resonance for wires with a diameter ranging from 100 to 500 nm and are compared with 2D finite element simulation. Fluctuation of the sample-substrate coupling is illustrated through its effect on the damping rate. We demonstrate elastic confinement in free standing wires which allowed the detection of up to the third harmonic of the breathing mode. By removing the energy relaxation channel towards the substrate, we obtained nano-oscillators with quality factors up to 130. Finally, taking advantage of the very high spectral resolution achieved on free standing wires, we could observe the elastic coupling between two close wires via their polymer cladding.

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

    NASA Astrophysics Data System (ADS)

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

    2011-03-01

    ZnO single crystal samples were implanted by oxygen with the energy of 150keV. After the pretreatment of hydrogen peroxide, 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 350& circ; C , 650& circ; C and 750& circ; C. Three peaks were identified in the DLTS spectra of the 900& circ; C sample, with the activation energies of 0.11eV, 0.25eV and 0.37eV respectively. The thermal evolutions of the deep levels up to the temperature of 1200& circ; C were also investigated. This work was supported by the RGC HKSAR under the GRF scheme (No. 703108P).

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

    NASA Astrophysics Data System (ADS)

    Murakami, Yoichi; Rice, William; Kono, Junichiro

    2007-03-01

    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.

  1. Transient analysis of single stage GM type double inlet pulse tube cryocooler

    NASA Astrophysics Data System (ADS)

    Gujarati, P. B.; Desai, K. P.; Naik, H. B.; Atrey, M. D.

    2015-12-01

    Transient analysis of single stage GM type double inlet pulse tube cryocooler is carried out using a one dimensional numerical model based on real gas properties of helium. The model solves continuity, momentum and energy equation for gas and solid to analyse the physical process occurring inside of the pulse tube cryocooler. Finite volume method is applied to discretize the governing equations with realistic initial and boundary conditions. Input data required for solving the model are the design data and operating parameters viz. pressure waveform from the compressor, regenerator matrix data, and system geometry including pulse tube, regenerator size and operating frequency for pulse tube cryocooler. The model investigates the effect of orifice opening, double inlet opening, pressure ratio, system geometry on no load temperature and refrigeration power at various temperatures for different charging pressure. The results are compared with experimental data and reasonable agreement is observed. The model can further be extended for designing two stage pulse tube cryocooler.

  2. PWR transient test documentation at San Onofre Nuclear Generating Station Unit 2

    SciTech Connect

    Betancourt, J.M.; Max, G.; Rezendes, J.P.; Veenema, R.J.; Cordes, G.

    1985-12-01

    This report provides the documentation of experimental data for six power ascension tests performed at the San Onofre Nuclear Generating Station Unit 2 during 1983. The tests conducted were: dropped control element assembly - full length, dropped control element assembly - part length, pseudo-ejected control element assembly, 100% generator trip, unit load transient, and the complete loss of forced primary coolant flow from 80% power. The data provided is expected to be useful for the qualification of computer codes used for predicting the transient response of Pressurized Water Reactors. A description of the data base containing these data is also included.

  3. Transient getter scheme for the Tokamak Fusion Test Reactor

    SciTech Connect

    Cecchi, J.L.; Cohen, S.A.; Sredniawski, J.J.

    1980-01-01

    The ability of the Tokamak Fusion Test Reactor (TFTR) to attain the largest fusion power gain depends critically on minimizing plasma contamination and controlling the densities of the reacting deuterium and tritium. Experiments on a number of tokamaks have demonstrated that gettering over an appreciable surface area (greater than or equal to 10%) of the vacuum vessel greatly facilitates both of these objectives. One particular problem in implementing a surface pumping system in TFTR, however, is a restriction on the maximum allowable tritium content of the getter. This restriction could require regeneration of the absorbed tritium after as few as 50 machine pulses. We have developed a scheme utilizing SAES Zr/Al getter modules which obviates the need for such frequent interruptions of machine operation by taking advantage of the pulsed operation of TFTR. With the Zr/Al getter at temperatures between 500/sup 0/C to 600/sup 0/C it is possible to achieve a quasi-steady state in the tritium loading where the quantity of tritium desorbed between pulses is equal to the quantity which is absorbed during a pulse. Since frequent thermal cycling is not required, this scheme also reduces the possibility of Zr/Al getter material fatigue.

  4. Electronically controlled mechanical seal for aerospace applications--Part 2: Transient tests

    NASA Technical Reports Server (NTRS)

    Wolff, Paul J.; Salant, Richard F.

    1995-01-01

    An electronically controlled mechanical seal for use as the purge gas seal in a liquid oxygen turbopump has been fabricated and tested under transient operating conditions. The thickness of the lubricating film is controlled by adjusting the coning of the carbon face. This is accomplished by applying a voltage to a piezoelectric actuator to which the carbon face is bonded. The seal has been operated with a closed-loop control system that utilizes either the leakage rate or seal face temperature as the feedback. Both speed and pressure transients have been imposed on the seal. The transient tests have demonstrated that the seal is capable of maintaing low leakage rates while limiting face temperatures.

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

    NASA Astrophysics Data System (ADS)

    Maillard, Pierre

    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 and tradeoffs based on design specifications, in conjunction with a broad set of guidelines for the design of hardened DLLs regarding circuit topology choices and parameter sensitivity on radiation exposure. We are confident that these results, tools, and guidelines will significantly expand the state-of-the-art in the design of hardened DLL clocking circuits for rad-hard applications.

  6. Transient Mitochondrial Depolarizations Reflect Focal Sarcoplasmic Reticular Calcium Release in Single Rat Cardiomyocytes

    PubMed Central

    Duchen, Michael R.; Leyssens, Anne; Crompton, Martin

    1998-01-01

    Digital imaging of mitochondrial potential in single rat cardiomyocytes revealed transient depolarizations of mitochondria discretely localized within the cell, a phenomenon that we shall call “flicker.” These events were usually highly localized and could be restricted to single mitochondria, but they could also be more widely distributed within the cell. Contractile waves, either spontaneous or in response to depolarization with 50 mM K+, were associated with propagating waves of mitochondrial depolarization, suggesting that propagating calcium waves are associated with mitochondrial calcium uptake and consequent depolarization. Here we demonstrate that the mitochondrial flicker was directly related to the focal release of calcium from sarcoplasmic reticular (SR) calcium stores and consequent uptake of calcium by local mitochondria. Thus, the events were dramatically reduced by (a) depletion of SR calcium stores after long-term incubation in EGTA or thapsigargin (500 nM); (b) buffering intracellular calcium using BAPTA-AM loading; (c) blockade of SR calcium release with ryanodine (30 μM); and (d) blockade of mitochondrial calcium uptake by microinjection of diaminopentane pentammine cobalt (DAPPAC), a novel inhibitor of the mitochondrial calcium uniporter. These observations demonstrate that focal SR calcium release results in calcium microdomains sufficient to promote local mitochondrial calcium uptake, suggesting a tight coupling of calcium signaling between SR release sites and nearby mitochondria. PMID:9722610

  7. Total Dose Effects on Single Event Transients in Linear Bipolar Systems

    NASA Technical Reports Server (NTRS)

    Buchner, Stephen; McMorrow, Dale; Bernard, Muriel; Roche, Nicholas; Dusseau, Laurent

    2008-01-01

    Single Event Transients (SETs) originating in linear bipolar integrated circuits are known to undermine the reliability of electronic systems operating in the radiation environment of space. Ionizing particle radiation produces a variety of SETs in linear bipolar circuits. The extent to which these SETs threaten system reliability depends on both their shapes (amplitude and width) and their threshold energies. In general, SETs with large amplitudes and widths are the most likely to propagate from a bipolar circuit's output through a subsystem. The danger these SET pose is that, if they become latched in a follow-on circuit, they could cause an erroneous system response. Long-term exposure of linear bipolar circuits to particle radiation produces total ionizing dose (TID) and/or displacement damage dose (DDD) effects that are characterized by a gradual degradation in some of the circuit's electrical parameters. For example, an operational amplifier's gain-bandwidth product is reduced by exposure to ionizing radiation, and it is this reduction that contributes to the distortion of the SET shapes. In this paper, we compare SETs produced in a pristine LM124 operational amplifier with those produced in one exposed to ionizing radiation for three different operating configurations - voltage follower (VF), inverter with gain (IWG), and non-inverter with gain (NIWG). Each configuration produces a unique set of transient shapes that change following exposure to ionizing radiation. An important finding is that the changes depend on operating configuration; some SETs decrease in amplitude, some remain relatively unchanged, some become narrower and some become broader.

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

    NASA Technical Reports Server (NTRS)

    Choi, Michael K.

    2004-01-01

    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.

  9. History-Dependent Excitability as a Single-Cell Substrate of Transient Memory for Information Discrimination

    PubMed Central

    Baroni, Fabiano; Torres, Joaquín J.; Varona, Pablo

    2010-01-01

    Neurons react differently to incoming stimuli depending upon their previous history of stimulation. This property can be considered as a single-cell substrate for transient memory, or context-dependent information processing: depending upon the current context that the neuron “sees” through the subset of the network impinging on it in the immediate past, the same synaptic event can evoke a postsynaptic spike or just a subthreshold depolarization. We propose a formal definition of History-Dependent Excitability (HDE) as a measure of the propensity to firing in any moment in time, linking the subthreshold history-dependent dynamics with spike generation. This definition allows the quantitative assessment of the intrinsic memory for different single-neuron dynamics and input statistics. We illustrate the concept of HDE by considering two general dynamical mechanisms: the passive behavior of an Integrate and Fire (IF) neuron, and the inductive behavior of a Generalized Integrate and Fire (GIF) neuron with subthreshold damped oscillations. This framework allows us to characterize the sensitivity of different model neurons to the detailed temporal structure of incoming stimuli. While a neuron with intrinsic oscillations discriminates equally well between input trains with the same or different frequency, a passive neuron discriminates better between inputs with different frequencies. This suggests that passive neurons are better suited to rate-based computation, while neurons with subthreshold oscillations are advantageous in a temporal coding scheme. We also address the influence of intrinsic properties in single-cell processing as a function of input statistics, and show that intrinsic oscillations enhance discrimination sensitivity at high input rates. Finally, we discuss how the recognition of these cell-specific discrimination properties might further our understanding of neuronal network computations and their relationships to the distribution and functional connectivity of different neuronal types. PMID:21203387

  10. Single cycle and transient force measurements in dynamic atomic force microscopy.

    PubMed

    Gadelrab, Karim; Santos, Sergio; Font, Josep; Chiesa, Matteo

    2013-11-21

    The monitoring of the deflection of a micro-cantilever, as the end of a sharp probe mounted at its end, i.e. the tip, interacts with a surface, forms the foundation of atomic force microscopy AFM. In a nutshell, developments in the field are driven by the requirement of obtaining ever increasing throughput and sensitivity, and enhancing the versatility of the instrument to simultaneously map the topography and quantify nanoscale processes and properties. In the most common dynamic mode of operation, the motion of the driven cantilever is monitored at a single point on its longitudinal axis. Here, we show that from this single point a waveform is obtained that contains all the details about conservative and dissipative interactions. Then a formalism that accounts for multiple arbitrary flexural modes is developed for an indirectly driven cantilever. The formalism is shown to allow recovery of the details of the interaction even in the presence of complex and relevant hysteretic forces when the cantilever oscillates in the steady state. In a different approach, we develop a formalism that monitors the wave profile of the cantilever, i.e. the waveform at five different points on its longitudinal axis. With this formalism the interaction can be reconstructed during a single oscillation cycle even in the transient state of oscillation. Finally, we discuss the potential and advantages of the proposed methods and future technical challenges. Other standard and state of the art techniques and methods are also discussed and compared with the ones presented here. This work should also provide insight into the current high throughput-high sensitivity developments dealing with multifrequency dynamic AFM where information is recovered from multiple eigenmodes. PMID:24071898

  11. Testing and Lubrication for Single Race Bearings

    SciTech Connect

    Steinhoff, R.G.

    1998-03-04

    Three ES and H-compatible lubricants (Environment, Safety and Health) for single race bearing applications and one hybrid-material single race bearings were evaluated and compared against single race bearings with trichlorotrifluoroethane (Freon) deposition of low molecular weight polytetrafluoroethylene (PTFE) bearing lubricant extracted from Vydax{trademark}. Vydax is a product manufactured by DuPont consisting of various molecular weights of PTFE suspended in trichlorotrifluoroethane (Freon), which is an ozone-depleting solvent. Vydax has been used as a bearing lubricant in stronglink mechanisms since 1974. Hybrid bearings with silicon nitride balls and molded glass-nylon-Teflon retainers, bearings lubricated with titanium carbide (TiC) on the balls, bearings lubricated with sputtered MoS{sub 2} on races and retainers, and bearings lubricated with electrophoretically deposited MoS{sub 2} were evaluated. The bearings were maintained in a preloaded state in bearing cartridges during cycling and vibration tests. Bearings with electrophoretically deposited MoS{sub 2} performed as well as bearings lubricated with Vydax and were the best performing candidate. All candidates were suitable for low preload applications. Bearings with TiC coated balls and bearings lubricated with sputtered MoS{sub 2} on the races and retainers performed well at high preloads, though not as well as bearings lubricated with electrophoretic deposition of MoS{sub 2}. Bearings with silicon nitride balls were not suitable for high preload applications.

  12. Steady-state and transient A/F control requirements for cold operation of a 1. 6 liter engine with single-point fuel injection

    SciTech Connect

    Aquino, C.F.; Fozo, S.R.

    1985-01-01

    An engine dynamometer test facility capable of controlling temperatures from 0/sup 0/F to 150/sup 0/F was used to investigate A/F control characteristics of a 1.6 liter engine with single point fuel injection. Two types of tests were run. In the first, the effect of induction system temperature on manifold wall wetting and transient A/F control was determined. In the second, a cold start procedure was developed to determine the effect of engine temperature on the percent of fuel which burns by observing exhaust A/F during steady-state operation while the engine warms up. It was found that transient A/F control problems due to manifold wall wetting are much greater than steady state problems associated with incomplete fuel burning.

  13. Transient oxidative stress and inflammation after intraperitoneal administration of multiwalled carbon nanotubes functionalized with single strand DNA in rats

    SciTech Connect

    Clichici, Simona; Biris, Alexandru Radu; Tabaran, Flaviu; Filip, Adriana

    2012-03-15

    Multi-walled carbon nanotubes (MWCNTs) are widely used for nanotechnology. Their impact on living organisms is, however, not entirely clarified. Oxidative stress and inflammation seem to be the key mechanisms involved in MWCNTs' cytotoxicity. Until present, pulmonary and skin models were the main tested experimental designs to assess carbon nanotubes' toxicity. The systemic administration of MWCNTs is essential, with respect for future medical applications. Our research is performed on Wistar rats and is focused on the dynamics of oxidative stress parameters in blood and liver and pro-inflammatory cytokines in liver, after single dose (270 mg l{sup −1}) ip administration of MWCNTs (exterior diameter 15–25 nm, interior diameter 10–15 nm, surface 88 m{sup 2} g{sup −1}) functionalized with single strand DNA (ss-DNA). The presence of MWCNTs in blood was assessed by Raman spectroscopy, while in liver histological examination and confocal microscopy were used. It was found that ss-DNA-MWCNTs induce oxidative stress in plasma and liver, with the return of the tested parameters to normal values, 6 h after ip injection of nanotubes, with the exception of reduced glutathione in plasma. The inflammatory cytokines (TNF-α, IL-1β) had a similar pattern of evolution. We also assessed the level of ERK1/2 and the phosphorylation of p65 subunit of NF-kB in liver that had a transient increase and returned to normal at the end of the tested period. Our results demonstrate that ss-DNA-MWCNTs produce oxidative stress and inflammation, but with a transient pattern. Given the fact that antioxidants modify the profile not only for oxidative stress, but also of inflammation, the dynamics of these alterations may be of practical importance for future protective strategies. -- Highlights: ► ss-DNA-MWCNTs ip administration induce oxidative stress in plasma and liver. ► ss-DNA-MWCNTs ip administration determine liver inflammation. ► ERK1/2 and p65 phosphorylated NF-KB increase in liver after MWCNTs ip injection. ► All the alterations, except plasma GSH, return to normal within 6 days.

  14. PHASE I SINGLE CELL ELECTROLYZER TEST RESULTS

    SciTech Connect

    Steimke, J; Timothy Steeper, T

    2008-08-05

    This document reports the results of Phase I Single Cell testing of an SO{sub 2}-Depolarized Water Electrolyzer. Testing was performed primarily during the first quarter of FY 2008 at the Savannah River National Laboratory (SRNL) using an electrolyzer cell designed and built at SRNL. Other facility hardware were also designed and built at SRNL. This test further advances this technology for which work began at SRNL in 2005. This research is valuable in achieving the ultimate goal of an economical hydrogen production process based on the Hybrid Sulfur (HyS) Cycle. The focus of this work was to conduct single cell electrolyzer tests to further develop the technology of SO{sub 2}-depolarized electrolysis as part of the HyS Cycle. The HyS Cycle is a hybrid thermochemical cycle that may be used in conjunction with advanced nuclear reactors or centralized solar receivers to produce hydrogen by water-splitting. Like all other sulfur-based cycles, HyS utilizes the high temperature thermal decomposition of sulfuric acid to produce oxygen and regenerate sulfur dioxide. The unique aspect of HyS is the generation of hydrogen in a water electrolyzer that is operated under conditions where dissolved sulfur dioxide depolarizes the anodic reaction, resulting in substantial voltage reduction. Low cell voltage is essential for both thermodynamic efficiency and hydrogen cost. Sulfur dioxide is oxidized at the anode, producing sulfuric acid that is sent to the high temperature acid decomposition portion of the cycle. The electrolyzer cell uses the membrane electrode assembly (MEA) concept. The anode and cathode are formed by spraying platinum containing catalyst on both sides of a Proton Exchange Membrane (PEM). In most testing the material of the PEM was NafionR. The electrolyzer cell active area can be as large as 54.8 cm{sup 2}. Feed to the anode of the electrolyzer is a sulfuric acid solution containing sulfur dioxide. The partial pressure of sulfur dioxide could be varied in the range of 1 to 6 atm (15 to 90 psia). Temperatures could be controlled in the range from ambient to 80 C. Hydrogen generated at the cathode of the cell was collected for the purpose of flow measurement and composition analysis. The test facility proved to be easy to operate, versatile, and reliable.

  15. The transient oxidation of single crystal NiAl+Zr. M.S. Thesis. Final Report

    NASA Technical Reports Server (NTRS)

    Doychak, J. K.

    1983-01-01

    The 800 C oxidation of oriented single crystals of Zr doped beta-NiAl was studied using transmission electron microscopy. The oxide phases and metal-oxide orientation relationships were determined to characterize the transient stages of oxidation prior to the transformation to or formation of alpha-Al2O3. On (001) and (012) metal orientations, NiAl2O4 was the first oxide to form followed by delta-Al2O3 which becomes the predominant oxide phase. All oxides were highly epitaxially related to the metal; the orientation relationships being function of parallel cation close-packed directions in the meta and oxide. On (011) and (111) metal orientations, gamma-Al2O3 became the predominant oxide phase rather than delta-Al2O3, indicating a structural stability from the highly epitaxial oxides. The relative concentration of aluminum in the oxide scales increased with time indicating preferential gamma-or delta-Al2O3 growth. The striking feature common to the orientation relationships is the alignment of 100 m and 110 ox directions, believed to result from the minimal 3 percent mismatch between the corresponding (100)m and (110)ox planes.

  16. Transient Rayleigh scattering: a new probe of picosecond carrier dynamics in a single semiconductor nanowire.

    PubMed

    Montazeri, Mohammad; Jackson, Howard E; Smith, Leigh M; Yarrison-Rice, Jan M; Kang, Jung-Hyun; Gao, Qiang; Tan, Hark Hoe; Jagadish, Chennupati

    2012-10-10

    Using a new technique, transient Rayleigh scattering, we show that measurements from a single GaAs/AlGaAs core-shell semiconductor nanowire provide sensitive and detailed information on the time evolution of the density and temperature of the electrons and holes after photoexcitation by an intense laser pulse. Through band filling, band gap renormalization, and plasma screening, the presence of a dense and hot electron-hole plasma directly influences the real and imaginary parts of the complex index of refraction that in turn affects the spectral dependence of the Rayleigh scattering cross-section in well-defined ways. By measuring this spectral dependence as a function of time, we directly determine the thermodynamically independent density and temperature of the electrons and holes as a function of time after pulsed excitation as the carriers thermalize to the lattice temperature. We successfully model the results by including ambipolar transport, recombination, and cooling through optic and acoustic phonon emission that quantify the hole mobility at ?68,000 cm(2)/Vs, linear decay constant at 380 ps, bimolecular recombination rate at 4.8 10(-9) cm(3)/s and the energy-loss rate of plasma due to optical and acoustic phonon emission. PMID:22974064

  17. Line-edge roughness induced single event transient variation in SOI FinFETs

    NASA Astrophysics Data System (ADS)

    Weikang, Wu; Xia, An; Xiaobo, Jiang; Yehua, Chen; Jingjing, Liu; Xing, Zhang; Ru, Huang

    2015-11-01

    The impact of process induced variation on the response of SOI FinFET to heavy ion irradiation is studied through 3-D TCAD simulation for the first time. When FinFET biased at OFF state configuration (Vgs = 0, Vds = Vdd) is struck by a heavy ion, the drain collects ionizing charges under the electric field and a current pulse (single event transient, SET) is consequently formed. The results reveal that with the presence of line-edge roughness (LER), which is one of the major variation sources in nano-scale FinFETs, the device-to-device variation in terms of SET is observed. In this study, three types of LER are considered: type A has symmetric fin edges, type B has irrelevant fin edges and type C has parallel fin edges. The results show that type A devices have the largest SET variation while type C devices have the smallest variation. Further, the impact of the two main LER parameters, correlation length and root mean square amplitude, on SET variation is discussed as well. The results indicate that variation may be a concern in radiation effects with the down scaling of feature size.

  18. Numerical simulation and experimental study of transient liquid phase bonding of single crystal superalloys

    NASA Astrophysics Data System (ADS)

    Ghoneim, Adam

    The primary goals of the research in this dissertation are to perform a systematic study to identify and understand the fundamental cause of prolonged processing time during transient liquid phase bonding of difficult-to-bond single crystal Ni-base materials, and use the acquired knowledge to develop an effective way to reduce the isothermal solidification time without sacrificing the single crystalline nature of the base materials. To achieve these objectives, a multi-scale numerical modeling approach, that involves the use of a 2-D fully implicit moving-mesh Finite Element method and a Cellular Automata method, was developed to theoretically investigate the cause of long isothermal solidification times and determine a viable way to minimize the problem. Subsequently, the predictions of the theoretical models are experimentally validated. Contrary to previous suggestions, numerical calculations and experimental verifications have shown that enhanced intergranular diffusivity has a negligible effect on solidification time in cast superalloys and that another important factor must be responsible. In addition, it was found that the concept of competition between solute diffusivity and solubility as predicted by standard analytical TLP bonding models and reported in the literature as a possible cause of long solidification times is not suitable to explain salient experimental observations. In contrast, however, this study shows that the problem of long solidification times, which anomalously increase with temperature is fundamentally caused by departure from diffusion controlled parabolic migration of the liquid-solid interface with holding time during bonding due to a significant reduction in the solute concentration gradient in the base material. Theoretical analyses showed it is possible to minimize the solidification time and prevent formation of stray-grains in joints between single crystal substrates by using a composite powder mixture of brazing alloy and base alloy as the interlayer material, which prior to the present work has been reported to be unsuitable. This was experimentally verified and the use of the composite powder mixture as interlayer material to reduce the solidification time and avoid stray-grain formation during TLP bonding of single crystal superalloys has been reported for the first time in this research.

  19. Transient single-longitudinal mode stabilization in double active layer GaInAsP/InP laser under high-bit rate modulation

    SciTech Connect

    Tsang, W.T.; Olsson, N.A.; Logan, R.A.

    1983-06-15

    We propose and demonstrate the operation of a new 1.3-..mu..m wavelength GaInAsP semiconductor laser: the double active layer (DAL) crescent laser and compared its device performances with regular single active layer (SAL) crescent laser fabricated under similar procedures. While the regular SAL crescent lasers (approx.250 ..mu..m cavity) tested were in general multilongitudinal moded, the DAL crescent lasers (both 300 and 125 ..mu..m) were highly single-longitudinal moded for the entire current range tested (up to 3I/sub th/), even under transient fast pulse excitation (high-bit rate modulation) and showed stability to mode hopping. DAL crescent lasers with short cavity (approx.125 ..mu..m) operated stably in the same single-longitudinal mode under fast constant current pulse excitation at all time starting from the onset of optical pulse and approach the characteristics of distributed Bragg reflector lasers in spectral purity and stability.

  20. Pressure transient tests on geothermal wells in the Dogger aquifer, Paris Basin

    NASA Astrophysics Data System (ADS)

    giuglaris, elodie; hamm, virginie

    2014-05-01

    In this work, we propose a new interpretation of pressure transient tests conducted in more than sixty wells targeting the Dogger formation in the Paris basin. The most part of these wells were drilled during the eighties over a very short period of time in an urban area. The transient tests were only recorded during a pressure buildup and show that contrary to what has long been assumed the Dogger aquifer behavior is not homogeneous. The interpretation of the obtained data was mainly done with Horner's method, independently for each well, and assuming generally that the aquifer is homogeneous. Available data from pressure transient tests are limited because of the precision of the tools used, and because pressure buildup was only recorded during eight to twelve hours. The objective was to determine the average transmissivity and the skin factor in order to obtain the productivity of the wells. We gather all available data, including those obtained on the thirteen recent wells, and propose a new interpretation in terms of aquifer model. We use the pressure derivative method developed in the nineties for oil reservoirs which allows a better visualization of the model and of the heterogeneity of the aquifer. Most of the well tests have a derivative pressure curve with a slope equal to zero, that does not change after the well bore effects, confirming that the aquifer is relatively homogenous. However on a dozen of wells, data from pressure transient tests display singular behaviors that can be related to a double porosity or double permeability model for some wells and to a composite model for others. These observations question the validity of a homogeneous model for the Dogger aquifer in the Paris basin and the currently used parameters for the thermal and hydrodynamic predictive model of geothermal exploitation. Finally, this work increases our understanding of the Dogger aquifer in the Paris basin and will allow the optimization of the ongoing hydraulic tests and the future exploitation of geothermal energy in the area.

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

    SciTech Connect

    Annette L. Schafer; A. Jeffrey Sondrup

    2013-11-01

    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.

  2. Single-event-transient effects in sub-70 nm bulk and SOI FinFETs

    NASA Astrophysics Data System (ADS)

    El Mamouni, Farah

    After fourteen years of research and investigations by engineers in the university and industry communities, FinFET devices are finally ready to use in products [1-2]. FinFET technologies have been demonstrated to outperform planar technologies for high speed, low power and high performance applications, while maintaining the shrinking trends of microelectronics (beyond 32 nm) for at least the next two to three technology generations. These promising findings were enough for leading chip manufacturers like Intel to announce their plans to mass-produce FinFETs in the near future [3-4]. However, the device response in extreme environments (i.e., space) is still not well understood. Exploring the behavior of FinFETs in such environments is also important for the aerospace and medical industries, where unhardened commercial off the shelf (COTS) electronics are used. The objective of this work is to explore the transient electrical behavior of FinFET devices in both bulk and SOI technologies in radiation-rich environments through laser and heavy ion testing. A further objective of this work is to contribute to improving the performance of FinFET devices, in particular in harsh environments. Indeed, the new results obtained in this work identify the physical regions in the devices that are most sensitive to radiation effects and how they affect the radiation response. The findings will help engineers to design new generations of FinFET devices with higher tolerance to radiation effects.

  3. Testing and analysis of structural integrity of electrosleeved tubes under severe accident transients

    SciTech Connect

    Majumdar, S.

    1999-12-10

    The structural integrity of flawed steam generator tubing with Electrosleeves{trademark} under simulated severe accident transients was analyzed by analytical models that used available material properties data and results from high-temperature tests conducted on Electrosleeved tubes. The Electrosleeve material is almost pure Ni and derives its strength and other useful properties from its nanocrystalline microstructure, which is stable at reactor operating temperatures. However, it undergoes rapid grain growth, at the high temperatures expected during severe accidents, resulting in a loss of strength and a corresponding decrease in flow stress. The magnitude of this decrease depends on the time-temperature history during the accident. Failure tests were conducted at ANL and FTI on internally pressurized Electrosleeved tubes with 80% and 100% throughwall machined axial notches in tie parent tubes that were subjected to simulated severe accident temperature transients. The test results, together with the analytical model, were used to estimate the unaged flow stress curve of the Electrosleeved material at high temperatures. Failure temperatures for Electrosleeved tubes with throughwall and part-throughwall axial cracks of various lengths in the parent tubes were calculated for a postulated severe accident transient.

  4. An infrastructure for accurate characterization of single-event transients in digital circuits☆

    PubMed Central

    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

    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

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

    PubMed

    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

    2013-11-01

    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

  6. Photosystem II single crystals studied by transient EPR: the light-induced triplet state.

    PubMed

    Kammel, Michael; Kern, Jan; Lubitz, Wolfgang; Bittl, Robert

    2003-08-18

    Transient electron paramagnetic resonance (TR EPR) at 9.8 GHz has been used to study the light-induced triplet state in single crystals of Photosystem II (PS II). The crystals were grown from a solution of PS II core complexes from the thermophilic cyanobacterium Synechococcus elongatus. The core complexes contain at least 17 subunits, including the water-oxidizing complex, and 32 chlorophyll a molecules per PS II complex. The PS II complexes are active in light-induced electron transfer and water oxidation. The crystals belong to the orthorhombic space group P2(1)2(1)2(1), with four dimers of PS II complexes per unit cell. Laser excitation was used to generate the recombination triplet state in PS II which was then studied by EPR at low temperatures (10 K). The crystal spectra show the same magnitude of the zero-field splitting (ZFS) values D, E as spectra obtained earlier for the triplet state of PS II in frozen solution. The orientation of the ZFS tensor D of the triplet state with respect to the crystallographic axes has been deduced from the analysis of angular-dependent EPR spectra. Knowledge of the orientation of the D tensor component perpendicular to the plane of the chlorophyll (D(Z)) allows an assignment on which chlorophyll of the reaction centre the triplet state is localized at low temperatures. Furthermore, the orientation of the D(X) and D(Y) components of the D tensor yielded the in-plane orientation of the respective chlorophyll in the reaction centre providing first experimental evidence for the orientation of this molecule in the PS II. PMID:12907300

  7. Effect of Holding Time on Microstructure and Properties of Transient Liquid-Phase-Bonded Joints of a Single Crystal Alloy

    NASA Astrophysics Data System (ADS)

    Chai, Lu; Huang, Jihua; Hou, Jinbao; Lang, Bo; Wang, Li

    2015-06-01

    Experimental investigations have been done to verify the effects of hold time during transient liquid-phase bonding on joint microstructure and mechanical properties of a nickel-based single crystal superalloy. The superalloy was bonded at 1473-1513 K for 0.25-12 h in vacuum environment. A set of parameters, 1513 K for 10 h, was determined as the optimum bonding condition. SEM results revealed that the joint without the completion of isothermal solidification is comprised of four different distinct regions, namely, rapid solidification zone (RSZ), isothermal solidification zone (ISZ), diffusion zone, and base metal. EBSD data indicated that the ISZ across the centerline of the bond has an undifferentiated crystallographic orientation being the same as the base metal. At increasing hold times at 1513 K, RSZ and also borides would disappear and result in an improvement of mechanical properties. Mechanical property tests at elevated temperatures have been done to determine the joints' quality. High-temperature creep rupture strength (for 100 h at 1373 K) and tensile strength (at 1273 K) of the joints could both attain 90% of those of the base metal.

  8. Transient Pressure Test Article (TPTA) 1.1 and 1.1A, volume 1

    NASA Technical Reports Server (NTRS)

    Rebells, Clarence A.

    1988-01-01

    This final test report presents the results obtained during the static hot firing and cold-gas high Q tests of the first Transient Pressure Test Article (TPTA) 1.1. The TPTA consisted of field test joints A and B, which were the original RSRM J-insulation configuration, with a metal capture feature. It also consisted of a flight configuration nozzle-to-case test joint (Joint D) with shorter vent slots. Fluorocarbon O-rings were used in all the test joints. The purpose of the TPTA tests is to evaluate and characterize the RSMR field and nozzle-to-case joints under the influence of ignition and strut loads during liftoff anf high Q. All objectives of the cold-gas high Q (TPTA 1.1A) test were met and all measurements were close to predicted values. During the static hot-firing test (TPTA 1.1), the motor was inadvertently plugged by the quench injector plug, making it a more severe test, although no strut loads were applied. The motor was depressurized after approximately 11 min using an auxiliary system, and no anomalies were noted. In the static hot-firing test, pressure was incident on the insulation and the test joint gaps were within the predicted range. During the static hot-firing test, no strut loads were applied because the loading system malfunctioned. For this test, all measurements were within range of similar tests performed without strut loads.

  9. Testing the ontogenetic base for the transient model of inflorescence development

    PubMed Central

    Bull-Hereu, Kester; Claen-Bockhoff, Regine

    2013-01-01

    Backgrounds and Aims Current research in plant science has concentrated on revealing ontogenetic processes of key attributes in plant evolution. One recently discussed model is the transient model successful in explaining some types of inflorescence architectures based on two main principles: the decline of the so called vegetativeness (veg) factor and the transient nature of apical meristems in developing inflorescences. This study examines whether both principles find a concrete ontogenetic correlate in inflorescence development. Methods To test the ontogenetic base of veg decline and the transient character of apical meristems the ontogeny of meristematic size in developing inflorescences was investigated under scanning electron microscopy. Early and late inflorescence meristems were measured and compared during inflorescence development in 13 eudicot species from 11 families. Key Results The initial size of the inflorescence meristem in closed inflorescences correlates with the number of nodes in the mature inflorescence. Conjunct compound inflorescences (panicles) show a constant decrease of meristematic size from early to late inflorescence meristems, while disjunct compound inflorescences present an enlargement by merging from early inflorescence meristems to late inflorescence meristems, implying a qualitative change of the apical meristems during ontogeny. Conclusions Partial confirmation was found for the transient model for inflorescence architecture in the ontogeny: the initial size of the apical meristem in closed inflorescences is consistent with the postulated veg decline mechanism regulating the size of the inflorescence. However, the observed biphasic kinetics of the development of the apical meristem in compound racemes offers the primary explanation for their disjunct morphology, contrary to the putative exclusive transient mechanism in lateral axes as expected by the model. PMID:23425784

  10. Nonlinear transient wave excitation as a new tool in model testing

    SciTech Connect

    Clauss, G.F.; Kuehnlein, W.L.

    1996-12-31

    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.

  11. Transient Thermal Testing and Analysis of a Thermally Insulating Structural Sandwich Panel

    NASA Technical Reports Server (NTRS)

    Blosser, Max L.; Daryabeigi, Kamran; Bird, Richard K.; Knutson, Jeffrey R.

    2015-01-01

    A core configuration was devised for a thermally insulating structural sandwich panel. Two titanium prototype panels were constructed to illustrate the proposed sandwich panel geometry. The core of one of the titanium panels was filled with Saffil(trademark) alumina fibrous insulation and the panel was tested in a series of transient thermal tests. Finite element analysis was used to predict the thermal response of the panel using one- and two-dimensional models. Excellent agreement was obtained between predicted and measured temperature histories.

  12. Test-Analysis Correlation and Finite Element Model Updating for Nonlinear Transient Dynamics

    SciTech Connect

    Hemez, F.M.; Doebling, S.W.

    1999-02-08

    This research aims at formulating criteria for measuring the correlation between test data and finite element results for nonlinear, transient dynamics. After reviewing the linear case and illustrating the limitations of modal-based updating when it is applied to nonlinear experimental data, simple time-domain, test-analysis correlation metrics are proposed. Two implementations are compared: the conventional least-squares technique and the Principal Component Decomposition that correlates subspaces rather than individual time-domain responses. Illustrations and discussions are provided using the LANL 8-DOF system, an experimental testbed for validating nonlinear data correlation and model updating techniques.

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

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

    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.

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

    SciTech Connect

    Deitrich, L. W.

    1998-07-28

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2009-12-01

    Recently, a technique has been developed whereby the radial velocity, Vr, and longitude direction, ?, 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 projective geometry, is based on the evaluation of the best fit of the time-elongation profile of the transient, extracted from a time-elongation map, to a set of theoretical functions corresponding to known combinations of radial velocity and direction; here we present an initial theoretical assessment of the efficacy of this technique. As the method relies on the manual selection of points along the time-elongation profile, an assessment of the accuracy with which this is feasible, is initially made. The work then presented assesses theoretically this method of recovering the velocity and propagation direction of solar transients from their time-elongation profiles using a Monte-Carlo simulation approach. In particular, we assess the range of elongations over which it is necessary to make observations in order to accurately recover these parameters. Results of the Monte-Carlo simulations suggest that it is sufficient to track a solar transient out to around 40 elongation to provide accurate estimates of its associated radial velocity and direction; the accuracy to which these parameters can be estimated for a transient tracked over a particular elongation extent is, however, sensitive to its velocity and direction relative to the Sun-Spacecraft line. These initial results suggest that this technique based on single spacecraft STEREO/HI observations could prove extremely useful in terms of providing an early warning of a CME impact on the near-Earth environment.

  16. Discussions On Worst-Case Test Condition For Single Event Burnout

    NASA Astrophysics Data System (ADS)

    Liu, Sandra; Zafrani, Max; Sherman, Phillip

    2011-10-01

    This paper discusses the failure characteristics of single- event burnout (SEB) on power MOSFETs based on analyzing the quasi-stationary avalanche simulation curves. The analyses show the worst-case test condition for SEB would be using the ion that has the highest mass that would result in the highest transient current due to charge deposition and displacement damage. The analyses also show it is possible to build power MOSFETs that will not exhibit SEB even when tested with the heaviest ion, which have been verified by heavy ion test data on SEB sensitive and SEB immune devices.

  17. Comparison of Single Event Transients Generated by Short Pulsed X-Rays, Lasers and Heavy Ions

    SciTech Connect

    Cardoza, David; LaLumondiere, Stephen D.; Tockstein, Michael A.; Brewe, Dale L.; Wells, Nathan P.; Koga, Rokutaro; Gaab, K. M.; Lotshaw, William T.; Moss, Steven C.

    2014-12-01

    We report an experimental study of the transients generated by pulsed x-rays, heavy ions, and different laser wavelengths in a Si p-i-n photodiode. We compare the charge collected by all of the excitation methods to determine the equivalent LET for pulsed x-rays relative to heavy ions. Our comparisons show that pulsed x-rays from synchrotron sources can generate a large range of equivalent LET and generate transients similar to those excited by laser pulses and heavy ion strikes. We also look at how the pulse width of the transients changes for the different excitation methods. We show that the charge collected with pulsed x-rays is greater than expected as the x-ray photon energy increases. Combined with their capability of focusing to small spot sizes and of penetrating metallization, pulsed x-rays are a promising new tool for high resolution screening of SEE susceptibility

  18. Oral glucose tolerance test should be performed after stroke and transient ischemic attack.

    PubMed

    Lindsberg, Perttu J; Tuomi, Tiinamaija; Kaste, Markku

    2011-08-01

    Diabetes mellitus predicts an increased risk of stroke, and acute hyperglycemia during acute stroke predicts the presence of undiagnosed diabetes mellitus. Based on recent investigations, 28% of previously nondiabetic stroke or transient ischemic attack patients have undetected diabetes mellitus, and 29% have impaired glucose tolerance, while only 43% have normal glycemic control. Oral glucose tolerance test is a far more sensitive and reliable test of diabetes mellitus than fasting blood glucose or HbA1c, and is recommended in the World Health Organization criteria for diagnosing diabetes mellitus and impaired glucose tolerance. Secondary prevention of stroke is different in patients with diabetes mellitus and the detection of impaired glucose tolerance would ring alarm bells of impending diabetes mellitus and promote lifestyle changes. As screening with inexpensive oral glucose tolerance test would have a hit rate of one in three patients in revealing undetected diabetes mellitus and another one in three in revealing impaired glucose tolerance, it should be implemented in guidelines as an inexpensive test for monitoring stroke and transient ischemic attack patients. PMID:21745342

  19. Predicting the Reliability of Brittle Material Structures Subjected to Transient Proof Test and Service Loading

    NASA Astrophysics Data System (ADS)

    Nemeth, Noel N.; Jadaan, Osama M.; Palfi, Tamas; Baker, Eric H.

    Brittle materials today are being used, or considered, for a wide variety of high tech applications that operate in harsh environments, including static and rotating turbine parts, thermal protection systems, dental prosthetics, fuel cells, oxygen transport membranes, radomes, and MEMS. Designing brittle material components to sustain repeated load without fracturing while using the minimum amount of material requires the use of a probabilistic design methodology. The NASA CARES/Life 1 (Ceramic Analysis and Reliability Evaluation of Structure/Life) code provides a general-purpose analysis tool that predicts the probability of failure of a ceramic component as a function of its time in service. This capability includes predicting the time-dependent failure probability of ceramic components against catastrophic rupture when subjected to transient thermomechanical loads (including cyclic loads). The developed methodology allows for changes in material response that can occur with temperature or time (i.e. changing fatigue and Weibull parameters with temperature or time). For this article an overview of the transient reliability methodology and how this methodology is extended to account for proof testing is described. The CARES/Life code has been modified to have the ability to interface with commercially available finite element analysis (FEA) codes executed for transient load histories. Examples are provided to demonstrate the features of the methodology as implemented in the CARES/Life program.

  20. Testing the single-state dominance hypothesis

    SciTech Connect

    lvarez-Rodrguez, R.; Moreno, O.; Moya de Guerra, E.; Sarriguren, P.; imkovic, F.; Faessler, A.

    2013-12-30

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

    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.

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

    NASA Technical Reports Server (NTRS)

    Yenni, Edward J.; Birchenough, Arthur G.

    1991-01-01

    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.

  3. Testing IH Instrumentation: Analysis of 1996-1998 Tank Ventilation Data in Terms of Characterizing a Transient Release

    SciTech Connect

    Droppo, James G.

    2004-07-01

    An analysis is conducted of the 1996-1998 Hanford tank ventilation studies of average ventilation rates to help define characteristics of shorter term releases. This effort is being conducted as part of the design of tests of Industrial Hygienes (IH) instrumentation ability to detect transient airborne plumes from tanks using current deployment strategies for tank operations. This analysis has improved our understanding of the variability of hourly average tank ventilation processes. However, the analysis was unable to discern the relative importance of emissions due to continuous releases and short-duration bursts of material. The key findings are as follows: 1. The ventilation of relatively well-sealed, passively ventilated tanks appears to be driven by a combination of pressure, buoyancy, and wind influences. The results of a best-fit analysis conducted with a single data set provide information on the hourly emission variability that IH instrumentation will need to detect. 2. Tank ventilation rates and tank emission rates are not the same. The studies found that the measured infiltration rates for a single tank are often a complex function of air exchanges between tanks and air exchanges with outdoor air. This situation greatly limits the usefulness of the ventilation data in defining vapor emission rates. 3. There is no evidence in the data to discern if the routine tank vapor releases occur over a short time (i.e., a puff) or over an extended time (i.e., continuous releases). Based on this analysis of the tank ventilation studies, it is also noted that 1) the hourly averaged emission peaks from the relatively well-sealed passively-vented tanks (such as U-103) are not a simple function of one meteorological parameter but the peaks often are the result of the coincidence of temporal maximums in pressure, temperature, and wind influences and 2) a mechanistic combination modeling approach and/or field studies may be necessary to understand the short-term temporal characteristics of transient releases - This requirement has implications in both the design of IH field tests and in understanding transient plumes during the times that worker complaints were recorded.

  4. Single Event Testing on Complex Devices: Test Like You Fly Versus Test-Specific Design Structures

    NASA Technical Reports Server (NTRS)

    Berg, Melanie D.; Label, Kenneth

    2016-01-01

    We present a mechanism for evaluating complex digital systems targeted for harsh radiation environments such as space. Focus is limited to analyzing the single event upset (SEU) susceptibility of designs implemented inside Field Programmable Gate Array (FPGA) devices. Tradeoffs are provided between application-specific versus test-specific test structures.

  5. Single event upset (SEU) testing at JPL

    NASA Technical Reports Server (NTRS)

    Coss, James R.

    1987-01-01

    It is believed that the increase in SEUs with more modern devices may have serious consequences for future space missions. The physics behind an SEU is discussed as well as SEU test philosophy and equipment, and testing results. It is concluded that the problem may be ameliorated by careful device selection and the use of redundancy or error correction.

  6. Stochastic expression of a multiple antibiotic resistance activator confers transient resistance in single cells

    PubMed Central

    El Meouche, Imane; Siu, Yik; Dunlop, Mary J.

    2016-01-01

    Transient resistance can allow microorganisms to temporarily survive lethal concentrations of antibiotics. This can be accomplished through stochastic mechanisms, where individual cells within a population display diverse phenotypes to hedge against the appearance of an antibiotic. To date, research on transient stochastic resistance has focused primarily on mechanisms where a subpopulation of cells enters a dormant, drug-tolerant state. However, a fundamental question is whether stochastic gene expression can also generate variable resistance levels among growing cells in a population. We hypothesized that stochastic expression of antibiotic-inducible resistance mechanisms might play such a role. To investigate this, we focused on a prototypical example of such a system: the multiple antibiotic resistance activator MarA. Previous studies have shown that induction of MarA can lead to a multidrug resistant phenotype at the population level. We asked whether MarA expression also has a stochastic component, even when uninduced. Time lapse microscopy showed that isogenic cells express heterogeneous, dynamic levels of MarA, which were correlated with transient antibiotic survival. This finding has important clinical implications, as stochastic expression of resistance genes may be widespread, allowing populations to hedge against the sudden appearance of an antibiotic. PMID:26758525

  7. Stochastic expression of a multiple antibiotic resistance activator confers transient resistance in single cells.

    PubMed

    El Meouche, Imane; Siu, Yik; Dunlop, Mary J

    2016-01-01

    Transient resistance can allow microorganisms to temporarily survive lethal concentrations of antibiotics. This can be accomplished through stochastic mechanisms, where individual cells within a population display diverse phenotypes to hedge against the appearance of an antibiotic. To date, research on transient stochastic resistance has focused primarily on mechanisms where a subpopulation of cells enters a dormant, drug-tolerant state. However, a fundamental question is whether stochastic gene expression can also generate variable resistance levels among growing cells in a population. We hypothesized that stochastic expression of antibiotic-inducible resistance mechanisms might play such a role. To investigate this, we focused on a prototypical example of such a system: the multiple antibiotic resistance activator MarA. Previous studies have shown that induction of MarA can lead to a multidrug resistant phenotype at the population level. We asked whether MarA expression also has a stochastic component, even when uninduced. Time lapse microscopy showed that isogenic cells express heterogeneous, dynamic levels of MarA, which were correlated with transient antibiotic survival. This finding has important clinical implications, as stochastic expression of resistance genes may be widespread, allowing populations to hedge against the sudden appearance of an antibiotic. PMID:26758525

  8. Modeling from Local to Subsystem Level Effects in Analog and Digital Circuits Due to Space Induced Single Event Transients

    NASA Technical Reports Server (NTRS)

    Perez, Reinaldo J.

    2011-01-01

    Single Event Transients in analog and digital electronics from space generated high energetic nuclear particles can disrupt either temporarily and sometimes permanently the functionality and performance of electronics in space vehicles. This work first provides some insights into the modeling of SET in electronic circuits that can be used in SPICE-like simulators. The work is then directed to present methodologies, one of which was developed by this author, for the assessment of SET at different levels of integration in electronics, from the circuit level to the subsystem level.

  9. Transverse spatial coherence of a transient nickellike silver soft-x-ray laser pumped by a single picosecond laser pulse

    NASA Astrophysics Data System (ADS)

    Lucianetti, A.; Janulewicz, K. A.; Kroemer, R.; Priebe, G.; Tmmler, J.; Sandner, W.; Nickles, P. V.; Redkorechev, V. I.

    2004-04-01

    The degree of spatial coherence in the direction perpendicular to the target surface is reported for a transient nickellike silver x-ray laser at 13.9 nm. An x-ray laser plasma column was produced by irradiating a slab silver target with a single shaped picosecond laser pulse with energy less than 3 J. Young's double-slit method was applied to measure the fringe visibility as a function of the slit separation for different target lengths. The diameter of the equivalent incoherent source and the coherence radius of the output radiation were determined as well.

  10. Deep level transient spectroscopy studies of n-type ZnO single crystals grown by different techniques.

    PubMed

    Scheffler, L; Kolkovsky, Vl; Lavrov, E V; Weber, J

    2011-08-24

    In the present study single-crystalline ZnO samples grown from the vapor phase, the melt, and a high-temperature aqueous solution (hydrothermal growth) are investigated before and after hydrogen plasma treatments, by means of deep level transient spectroscopy (DLTS) and high-resolution Laplace DLTS. Dominant DLTS peaks are found to appear in the range of 120-350 K for all materials. The DLTS spectra depend on the procedure of growth of the ZnO. The thermal stabilities of the defects in an oxygen atmosphere and in an oxygen-lean atmosphere are analyzed. The origin of the DLTS peaks is discussed. PMID:21813951

  11. Viral Transmission Dynamics at Single-Cell Resolution Reveal Transiently Immune Subpopulations Caused by a Carrier State Association

    PubMed Central

    Cenens, William; Makumi, Angela; Govers, Sander K.; Lavigne, Rob; Aertsen, Abram

    2015-01-01

    Monitoring the complex transmission dynamics of a bacterial virus (temperate phage P22) throughout a population of its host (Salmonella Typhimurium) at single cell resolution revealed the unexpected existence of a transiently immune subpopulation of host cells that emerged from peculiarities preceding the process of lysogenization. More specifically, an infection event ultimately leading to a lysogen first yielded a phage carrier cell harboring a polarly tethered P22 episome. Upon subsequent division, the daughter cell inheriting this episome became lysogenized by an integration event yielding a prophage, while the other daughter cell became P22-free. However, since the phage carrier cell was shown to overproduce immunity factors that are cytoplasmically inherited by the P22-free daughter cell and further passed down to its siblings, a transiently resistant subpopulation was generated that upon dilution of these immunity factors again became susceptible to P22 infection. The iterative emergence and infection of transiently resistant subpopulations suggests a new bet-hedging strategy by which viruses could manage to sustain both vertical and horizontal transmission routes throughout an infected population without compromising a stable co-existence with their host. PMID:26720743

  12. Carrier Dynamics in a-Fe2O3 (0001) Thin Films and Single Crystals Probed by Femtosecond Transient Absorption and Reflectivity

    SciTech Connect

    Joly, Alan G.; Williams, Josh R.; Chambers, Scott A.; Xiong, Gang; Hess, Wayne P.; Laman, David M.

    2006-03-01

    Femtosecond transient reflectivity and absorption is used to measure the carrier lifetimes in ?-Fe2O3 thin films and hematite single crystals. The results from the thin films show that initially excited hot electrons relax to the bandedge within 300 femtoseconds and then recombine with holes or trap within 5 pioseconds. The trapped electrons have a lifetime of hundreds of picoseconds. The trapped electrons have a lifetime of hundreds of picoseconds. Transient reflectivity measurements from hematite (?-Fe2O3) single crystals show similar but slightly faster dynamics. In hematite, the transient reflectivity displays oscillations due to the formation of longitudinal acoustic phonons generated following absorption of the ultrashort excitation pulse.

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

    NASA Technical Reports Server (NTRS)

    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

    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.

  14. The Use of Randomization Tests in Single-Subject Research

    ERIC Educational Resources Information Center

    Haardorfer, Regine; Gagne, Phill

    2010-01-01

    Some researchers have argued for the use of or have attempted to make use of randomization tests in single-subject research. To address this tide of interest, the authors of this article describe randomization tests, discuss the theoretical rationale for applying them to single-subject research, and provide an overview of the methodological…

  15. The Use of Randomization Tests in Single-Subject Research

    ERIC Educational Resources Information Center

    Haardorfer, Regine; Gagne, Phill

    2010-01-01

    Some researchers have argued for the use of or have attempted to make use of randomization tests in single-subject research. To address this tide of interest, the authors of this article describe randomization tests, discuss the theoretical rationale for applying them to single-subject research, and provide an overview of the methodological

  16. Cross-borehole flowmeter tests for transient heads in heterogeneous aquifers.

    PubMed

    Le Borgne, Tanguy; Paillet, Frederick; Bour, Olivier; Caudal, Jean-Pierre

    2006-01-01

    Cross-borehole flowmeter tests have been proposed as an efficient method to investigate preferential flowpaths in heterogeneous aquifers, which is a major task in the characterization of fractured aquifers. Cross-borehole flowmeter tests are based on the idea that changing the pumping conditions in a given aquifer will modify the hydraulic head distribution in large-scale flowpaths, producing measurable changes in the vertical flow profiles in observation boreholes. However, inversion of flow measurements to derive flowpath geometry and connectivity and to characterize their hydraulic properties is still a subject of research. In this study, we propose a framework for cross-borehole flowmeter test interpretation that is based on a two-scale conceptual model: discrete fractures at the borehole scale and zones of interconnected fractures at the aquifer scale. We propose that the two problems may be solved independently. The first inverse problem consists of estimating the hydraulic head variations that drive the transient borehole flow observed in the cross-borehole flowmeter experiments. The second inverse problem is related to estimating the geometry and hydraulic properties of large-scale flowpaths in the region between pumping and observation wells that are compatible with the head variations deduced from the first problem. To solve the borehole-scale problem, we treat the transient flow data as a series of quasi-steady flow conditions and solve for the hydraulic head changes in individual fractures required to produce these data. The consistency of the method is verified using field experiments performed in a fractured-rock aquifer. PMID:16681524

  17. Performance of a bulb turbine suitable for low prototype head: model test and transient numerical simulation

    NASA Astrophysics Data System (ADS)

    Zhu, L.; Zhang, H. P.; Zhang, J. G.; Meng, X. C.; Lu, L.

    2012-11-01

    In this paper, a bulb turbine, with unit specific speed of nq=223.1 min-1 suitable for low prototype head was studied from aspect of its performance. Hydraulic model of the turbine was developed firstly, and then model turbine was designed and manufactured. Performance tests were carried out on high-accuracy hydraulic machinery model universal test rig located at IWHR, including energy, cavitation and pressure fluctuation tests, etc. In order to investigate internal flow field, three-dimensional transient turbulence numerical simulation was conducted on the tested turbine, adopting Reynolds-averaged Navier-Stocks control equations and RNG k-ɛ turbulence model. Test and simulation results show that: (1) hydraulic efficiency of model turbine ηM is up to 91.7%, at the optimum operating point of n11o=165.54 r/min versus Q11o=1.93 m3/s; (2) numerical results agree well with experimental resultsby comparing pressure fluctuation, which shows that pressure amplitude is very low at the optimum operating point; (3) hydraulic loss in Outflow domain accounts for more than 50% total hydraulic loss due to flow separation and secondary flow.

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

    SciTech Connect

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

    1990-01-01

    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.

  19. Transient characteristic analysis of an HTS DC power cable using a multi-terminal based test-bed

    NASA Astrophysics Data System (ADS)

    Kim, Jin-Geun; Dinh, Minh-Chau; Kim, Sung-Kyu; Park, Minwon; Yu, In-Keun; Yang, Byeongmo

    2013-11-01

    The current capacity of a power supply limits the experimental environment of higher capacity HTS power cable. Consequently, the transient characteristic analysis of an HTS DC power cable is difficult to assess. In this paper, a multi-terminal based test-bed is used to overcome those power supply capacity limitations. A 1 kA class HTS DC power cable was designed and the transient characteristics of the HTS DC power cable were analyzed using the multi-terminal based test-bed. Transient characteristics, such as resistance variation and critical current of the 1 kA class HTS DC power cable were successfully measured using small power sources in the multi-terminal based test-bed. Definitely, the suggested test system overcomes the assessment limits of the HTS power cables current capacity.

  20. Effects of drain-wall in mitigating N-hit single event transient via 45 nm CMOS process

    NASA Astrophysics Data System (ADS)

    Y Xu, X.; Xiong, Y.; Tang, M. H.; Xiao, Y. G.; Yan, S. A.; Zhang, W. L.; Zhao, W.; Guo, H. X.; Li, Z.

    2015-01-01

    A three-dimensional (3D) technology computer-aided design (TCAD) simulation in a novel layout technique for N-hit single event transient (SET) mitigation based on drain-wall layout technique is proposed. Numerical simulations of both single-device and mixed-mode show that the proposed layout technique designed with 45 nm CMOS process can efficiently reduce not only charge collection but also SET pulse widths (WSET). What is more, simulations show that impacts caused by part of ion-incidents can be shielded with this novel layout technique. When compared with conventional layout technique and guard drain layout technique, we find that the proposed novel layout technique can provide the best benefit of SET mitigation with a small sacrifice in effective area.

  1. Transient Plume Model Testing Using LADEE Spacecraft Attitude Control System Operations

    SciTech Connect

    Woronowicz, M. S.

    2011-05-20

    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/cm{sup 3}. 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.

  2. Transient Plume Model Testing Using LADEE Spacecraft Attitude Control System Operations

    NASA Technical Reports Server (NTRS)

    Woronowicz, M. S.

    2010-01-01

    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.

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

    SciTech Connect

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

    2011-08-01

    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.

  4. Heat and Mass Transfer Analysis of Dehumidifiers Using Adiabatic Transient Tests

    SciTech Connect

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

    1986-04-01

    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.

  5. Single Event Effects (SEE) Testing: Practical Approach to Test Plans

    NASA Technical Reports Server (NTRS)

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

    2014-01-01

    While standards and guidelines for performing SEE testing have existed for several decades, guidance for developing SEE test plans has not been as easy to find. In this presentation, the variety of areas that need to be considered ranging from resource issues (funds, personnel, schedule) to extremely technical challenges (particle interaction and circuit application), shall be discussed. Note: 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.

  6. Barometric pressure transient testing applications at the Nevada Test Site. Nuclear chimney analysis. Final report

    SciTech Connect

    Hanson, J.M.

    1985-12-01

    Investigations of barometric pressure testing of NTS nuclear chimneys were reviewed. This review includes the models used in the interpretation, methods of analysis, and results. Analytic and semi-analytic models were presented and applied to both historical data and new data taken for this current project. An interpretation technique based on non-linear least squares methods was used to analyze this data in terms of historic and more recent chimney models. Finally, a detailed discussion of radioactive gas transport due to surface barometric pressure fluctuations was presented. This mechanism of transport, referred to as ''barometric pumping,'' is presented in terms of conditions likely to be encountered at the NTS. The report concludes with a discussion of the current understanding of gas flow properties in the alluvial and volcanic areas of the NTS, and suggestions for future efforts directed toward increasing this understanding are presented.

  7. Photo-induced current transient spectroscopy of single crystal Tl6I4Se

    NASA Astrophysics Data System (ADS)

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

    2014-11-01

    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.

  8. Single-Molecule Measurements of Transient Biomolecular Complexes through Microfluidic Dilution

    PubMed Central

    2013-01-01

    Single-molecule confocal microscopy experiments require concentrations which are low enough to guarantee that, on average, less than one single molecule resides in the probe volume at any given time. Such concentrations are, however, significantly lower than the dissociation constants of many biological complexes which can therefore dissociate under single-molecule conditions. To address the challenge of observing weakly bound complexes in single-molecule experiments in solution, we have designed a microfluidic device that rapidly dilutes samples by up to one hundred thousand times, allowing the observation of unstable complexes before they dissociate. The device can interface with standard biochemistry laboratory experiments and generates a spatially uniform dilution that is stable over time allowing the quantification of the relative concentrations of different molecular species. PMID:23782428

  9. Single shaft automotive gas turbine engine characterization test

    NASA Technical Reports Server (NTRS)

    Johnson, R. A.

    1979-01-01

    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.

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

    SciTech Connect

    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

    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.).

  11. High-throughput testing of terpenoid biosynthesis candidate genes using transient expression in Nicotiana benthamiana.

    PubMed

    Bach, Sren Spanner; Bassard, Jean-tienne; Andersen-Ranberg, Johan; Mldrup, Morten Emil; Simonsen, Henrik Toft; Hamberger, Bjrn

    2014-01-01

    To respond to the rapidly growing number of genes putatively involved in terpenoid metabolism, a robust high-throughput platform for functional testing is needed. An in planta expression system offers several advantages such as the capacity to produce correctly folded and active enzymes localized to the native compartments, unlike microbial or prokaryotic expression systems. Two inherent drawbacks of plant-based expression systems, time-consuming generation of transgenic plant lines and challenging gene-stacking, can be circumvented by transient expression in Nicotiana benthamiana. In this chapter we describe an expression platform for rapid testing of candidate terpenoid biosynthetic genes based on Agrobacterium mediated gene expression in N. benthamiana leaves. Simultaneous expression of multiple genes is facilitated by co-infiltration of leaves with several engineered Agrobacterium strains, possibly making this the fastest and most convenient system for the assembly of plant terpenoid biosynthetic routes. Tools for cloning of expression plasmids, N. benthamiana culturing, Agrobacterium preparation, leaf infiltration, metabolite extraction, and automated GC-MS data mining are provided. With all steps optimized for high throughput, this in planta expression platform is particularly suited for testing large panels of candidate genes in all possible permutations. PMID:24777803

  12. Optical micro-spectroscopy of single metallic nanoparticles: quantitative extinction and transient resonant four-wave mixing.

    PubMed

    Payne, Lukas; Zoriniants, George; Masia, Francesco; Arkill, Kenton P; Verkade, Paul; Rowles, Darren; Langbein, Wolfgang; Borri, Paola

    2015-12-12

    We report a wide-field imaging method to rapidly and quantitatively measure the optical extinction cross-section ?ext (also polarisation resolved) of a large number of individual gold nanoparticles, for statistically-relevant single particle analysis. We demonstrate a sensitivity of 5 nm(2) in ?ext, enabling detection of single 5 nm gold nanoparticles with total acquisition times in the 1 min range. Moreover, we have developed an analytical model of the polarisation resolved ?ext, which enabled us to extract geometrical particle aspect ratios from the measured ?ext. Using this method, we have characterized a large number of nominally-spherical gold nanoparticles in the 10-100 nm size range. Furthermore, the method provided measurements of in-house fabricated nanoparticle conjugates, allowing distinction of individual dimers from single particles and larger aggregates. The same particle conjugates were investigated correlatively by phase-resolved transient resonant four-wave mixing micro-spectroscopy. A direct comparison of the phase-resolved response between single gold nanoparticles and dimers highlighted the promise of the four-wave mixing technique for sensing applications with dimers as plasmon rulers. PMID:26416674

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

    SciTech Connect

    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

    2014-02-01

    This document contains the analysis details and summary of analyses conducted to evaluate the environmental impacts for the Resumption of Transient Fuel and Materials Testing Program. It provides an assessment of the impacts for the two action alternatives being evaluated in the environmental assessment. These alternatives are (1) resumption of transient testing using the Transient Reactor Test Facility (TREAT) at Idaho National Laboratory (INL) and (2) conducting transient testing using the Annular Core Research Reactor (ACRR) at Sandia National Laboratory in New Mexico (SNL/NM). Analyses are provided for radiologic emissions, other air emissions, soil contamination, and groundwater contamination that could occur (1) during normal operations, (2) as a result of accidents in one of the facilities, and (3) during transport. It does not include an assessment of the biotic, cultural resources, waste generation, or other impacts that could result from the resumption of transient testing. Analyses were conducted by technical professionals at INL and SNL/NM as noted throughout this report. The analyses are based on bounding radionuclide inventories, with the same inventories used for test materials by both alternatives and different inventories for the TREAT Reactor and ACRR. An upper value on the number of tests was assumed, with a test frequency determined by the realistic turn-around times required between experiments. The estimates provided for impacts during normal operations are based on historical emission rates and projected usage rates; therefore, they are bounding. Estimated doses for members of the public, collocated workers, and facility workers that could be incurred as a result of an accident are very conservative. They do not credit safety systems or administrative procedures (such as evacuation plans or use of personal protective equipment) that could be used to limit worker doses. Doses estimated for transportation are conservative and are based on transport of the bounding radiologic inventory that will be contained in any given test. The transportation analysis assumes all transports will contain the bounding inventory.

  14. Properties of voltage-activated [Ca2+]i transients in single smooth muscle cells isolated from pregnant rat uterus

    PubMed Central

    Shmigol, A V; Eisner, D A; Wray, Susan

    1998-01-01

    The intracellular calcium concentration ([Ca2+]i) was measured at 35 °C using the fluorescent indicator indo-1 in patch-clamped, single uterine myocytes from pregnant rats to investigate the relationship between depolarization, Ca2+ current (ICa) and [Ca2+]i. Membrane depolarization activated ICa and produced a [Ca2+]i transient. The rapid increase in [Ca2+]i occurred at the same time as the inward ICa. Both ICa and the increase in [Ca2+]i were abolished by nifedipine (10 μm). When the membrane potential was held at -80 mV the threshold depolarization for an increase in [Ca2+]i was about -55 to -50 mV. As the magnitude of the depolarization was increased to about 0 mV there was an increase in the size of both ICa and the increase in [Ca2+]i. As the magnitude of the depolarization was further increased both ICa and the [Ca2+]i increase declined. When the depolarizing pulses were applied at 3 Hz to mimic normal action potentials then the individual [Ca2+]i transients did not fully relax and a tetanic rise of [Ca2+]i was observed. Under these conditions, there was not a simple relationship between the magnitude of the Ca2+ response and Ca2+ entry. When pairs of depolarizing pulses were applied, the increase in [Ca2+]i produced by the second pulse was larger (in relation to the magnitude of the L-type Ca2+ current) than that produced by the first pulse. This facilitation was abolished by both ryanodine and cyclopiazonic acid suggesting a role for release from intracellular stores. We conclude that the L-type Ca2+ current is the major source of Ca2+ ions entering the cell to produce the [Ca2+]i transient on depolarization. The magnitude of the increase in [Ca2+]i may, however, be amplified by Ca2+-induced Ca2+ release. PMID:9714861

  15. High intensity single bunch operation with heavy periodic transient beam loading in wide band rf cavities

    NASA Astrophysics Data System (ADS)

    Tamura, Fumihiko; Hotchi, Hideaki; Schnase, Alexander; Yoshii, Masahito; Yamamoto, Masanobu; Ohmori, Chihiro; Nomura, Masahiro; Toda, Makoto; Shimada, Taihei; Hasegawa, Katsushi; Hara, Keigo

    2015-09-01

    The rapid cycling synchrotron (RCS) in the Japan Proton Accelerator Research Complex (J-PARC) was originally designed to accelerate two high intensity bunches, while some of neutron experiments in the materials and life science experimental facility and a muon experiment using main ring beams require a single bunch operation mode, in which one of the two rf buckets is filled and the other is empty. The beam intensity in the single bunch operation has been limited by longitudinal beam losses due to the rf bucket distortions by the wake voltage of the odd harmonics (h =1 ,3 ,5 ) in the wide band magnetic alloy cavities. We installed an additional rf feedforward system to compensate the wake voltages of the odd harmonics (h =1 ,3 ,5 ). The additional system has a similar structure as the existing feedforward system for the even harmonics (h =2 ,4 ,6 ). We describe the function of the feedforward system for the odd harmonics, the commissioning methodology, and the commissioning results. The longitudinal beam losses during the single bunch acceleration disappeared with feedforward for the odd harmonics. We also confirmed that the beam quality in the single bunch acceleration are similar to that of the normal operation with two bunches. Thus, high intensity single bunch acceleration at the intensity of 2.3 ×1013 protons per bunch has been achieved in the J-PARC RCS. This article is a follow-up of our previous article, Phys. Rev. ST Accel. Beams 14, 051004 (2011). The feedforward system extension for single bunch operation was successful.

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

    NASA Technical Reports Server (NTRS)

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

    2003-01-01

    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.

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

    SciTech Connect

    Hemez, F. M.; Ben-Haim, Yakov,; Cogan, S.

    2002-01-01

    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.

  18. 49 CFR 238.311 - Single car test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a... 49 Transportation 4 2011-10-01 2011-10-01 false Single car test. 238.311 Section 238.311... Requirements for Tier I Passenger Equipment § 238.311 Single car test. (a) Except for self-propelled...

  19. 49 CFR 238.311 - Single car test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a... 49 Transportation 4 2013-10-01 2013-10-01 false Single car test. 238.311 Section 238.311... Requirements for Tier I Passenger Equipment § 238.311 Single car test. (a) Except for self-propelled...

  20. 49 CFR 238.311 - Single car test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a... 49 Transportation 4 2014-10-01 2014-10-01 false Single car test. 238.311 Section 238.311... Requirements for Tier I Passenger Equipment § 238.311 Single car test. (a) Except for self-propelled...

  1. 49 CFR 238.311 - Single car test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a... 49 Transportation 4 2012-10-01 2012-10-01 false Single car test. 238.311 Section 238.311... Requirements for Tier I Passenger Equipment § 238.311 Single car test. (a) Except for self-propelled...

  2. Single-well chemical tracer tests since 1968

    SciTech Connect

    Majoros, S.; Deans, H.A.

    1980-07-01

    The results of 59 single-well chemical tracer tests to measure residual oil saturation, S/sub OR/, are reported. These tests have been run by Exxon Production Research Company and its licensees since 1968 in over thirty reservoirs. The data reported are the test conditions and produced tracer concentration profiles. We have correlated the distribution coefficients and hydrolysis rate constants for the most commonly used tracers to facilitate design of future tests.

  3. Characterization of deep level defects in Tl6I4S single crystals by photo-induced current transient spectroscopy

    NASA Astrophysics Data System (ADS)

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

    2015-02-01

    Defect levels in semi-insulating Tl6I4S single crystals grown by the horizontal Bridgman technique have been characterized using photo-induced current transient spectroscopy (PICTS). These measurements revealed six electron traps located at (0.059? ?0.007), (0.13? ?0.012), (0.31? ?0.074), (0.39? ?0.019), (0.62? ?0.110), and (0.597? ?0.105). These defect levels are attributed to vacancies (VI, VS) and antisite defects (IS, TlS, TlI) upon comparison to calculations of native defect energy levels using density functional theory and defects recently reported from photoluminescence and photoconductivity measurements.

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

    NASA Astrophysics Data System (ADS)

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

    2014-09-01

    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.

  5. Modeling of single event transients with dual double-exponential current sources: Implications for logic cell characterization

    SciTech Connect

    Black, Dolores A.; Robinson, William H.; Limbrick, Daniel B.; Black, Jeffrey D.; Wilcox, Ian Z.

    2015-08-07

    Single event effects (SEE) are a reliability concern for modern microelectronics. Bit corruptions can be caused by single event upsets (SEUs) in the storage cells or by sampling single event transients (SETs) from a logic path. An accurate prediction of soft error susceptibility from SETs requires good models to convert collected charge into compact descriptions of the current injection process. This paper describes a simple, yet effective, method to model the current waveform resulting from a charge collection event for SET circuit simulations. The model uses two double-exponential current sources in parallel, and the results illustrate why a conventional model based on one double-exponential source can be incomplete. A small set of logic cells with varying input conditions, drive strength, and output loading are simulated to extract the parameters for the dual double-exponential current sources. Furthermore, the parameters are based upon both the node capacitance and the restoring current (i.e., drive strength) of the logic cell.

  6. Modeling of single event transients with dual double-exponential current sources: Implications for logic cell characterization

    DOE PAGESBeta

    Black, Dolores Archuleta; Robinson, William H.; Wilcox, Ian Zachary; Limbrick, Daniel B.; Black, Jeffrey D.

    2015-08-07

    Single event effects (SEE) are a reliability concern for modern microelectronics. Bit corruptions can be caused by single event upsets (SEUs) in the storage cells or by sampling single event transients (SETs) from a logic path. Likewise, an accurate prediction of soft error susceptibility from SETs requires good models to convert collected charge into compact descriptions of the current injection process. This paper describes a simple, yet effective, method to model the current waveform resulting from a charge collection event for SET circuit simulations. The model uses two double-exponential current sources in parallel, and the results illustrate why a conventionalmore » model based on one double-exponential source can be incomplete. Furthermore, a small set of logic cells with varying input conditions, drive strength, and output loading are simulated to extract the parameters for the dual double-exponential current sources. As a result, the parameters are based upon both the node capacitance and the restoring current (i.e., drive strength) of the logic cell.« less

  7. Modeling of single event transients with dual double-exponential current sources: Implications for logic cell characterization

    DOE PAGESBeta

    Black, Dolores A.; Robinson, William H.; Limbrick, Daniel B.; Black, Jeffrey D.; Wilcox, Ian Z.

    2015-08-07

    Single event effects (SEE) are a reliability concern for modern microelectronics. Bit corruptions can be caused by single event upsets (SEUs) in the storage cells or by sampling single event transients (SETs) from a logic path. An accurate prediction of soft error susceptibility from SETs requires good models to convert collected charge into compact descriptions of the current injection process. This paper describes a simple, yet effective, method to model the current waveform resulting from a charge collection event for SET circuit simulations. The model uses two double-exponential current sources in parallel, and the results illustrate why a conventional modelmore » based on one double-exponential source can be incomplete. A small set of logic cells with varying input conditions, drive strength, and output loading are simulated to extract the parameters for the dual double-exponential current sources. Furthermore, the parameters are based upon both the node capacitance and the restoring current (i.e., drive strength) of the logic cell.« less

  8. Statistics of the transient frequency modulation in the switch-on of a single-mode semiconductor laser

    NASA Astrophysics Data System (ADS)

    Balle, Salvador; de Pasquale, F.; Abraham, N. B.; San Miguel, M.

    1992-02-01

    The variations of the optical frequency during the switch-on of a single-mode semiconductor laser diode have been studied. Our model relies on stochastic rate equations, and therefore a meaningful description of the laser frequency in the presence of both noise and transient evolution is difficult. The relation between an approximately instantaneous frequency that we calculate numerically and experimentally measured frequencies is discussed. We analyze the frequency variations during switch-on processes and the statistical properties of the nearly instantaneous frequency that we chose as the most reasonable to calculate. The range of the frequency chirp during the first pulse of the intensity is stochastic, but it is correlated with the switch-on time, and therefore its statistical properties can be deduced from those of the first-passage-time distribution. The correlations permit a single discriminator to select a subset of pulses with similar peak intensities, delay times, and chirp ranges. In addition, there are significant differences between the averaged quantities and results for a single switch-on.

  9. Modeling of single event transients with dual double-exponential current sources: Implications for logic cell characterization

    SciTech Connect

    Black, Dolores Archuleta; Robinson, William H.; Wilcox, Ian Zachary; Limbrick, Daniel B.; Black, Jeffrey D.

    2015-08-07

    Single event effects (SEE) are a reliability concern for modern microelectronics. Bit corruptions can be caused by single event upsets (SEUs) in the storage cells or by sampling single event transients (SETs) from a logic path. Likewise, an accurate prediction of soft error susceptibility from SETs requires good models to convert collected charge into compact descriptions of the current injection process. This paper describes a simple, yet effective, method to model the current waveform resulting from a charge collection event for SET circuit simulations. The model uses two double-exponential current sources in parallel, and the results illustrate why a conventional model based on one double-exponential source can be incomplete. Furthermore, a small set of logic cells with varying input conditions, drive strength, and output loading are simulated to extract the parameters for the dual double-exponential current sources. As a result, the parameters are based upon both the node capacitance and the restoring current (i.e., drive strength) of the logic cell.

  10. Anomalous transient uplift observed at the Lop Nor, China nuclear test site using satellite radar interferometry time-series analysis

    NASA Astrophysics Data System (ADS)

    Vincent, P.; Buckley, S. M.; Yang, D.; Carle, S. F.

    2011-12-01

    Anomalous uplift is observed at the Lop Nor, China nuclear test site using ERS satellite SAR data. Using an InSAR time-series analysis method, we show that an increase in absolute uplift with time is observed between 1997 and 1999. The signal is collocated with past underground nuclear tests. Due to the collocation in space with past underground tests we postulate a nuclear test-related hydrothermal source for the uplift signal. A possible mechanism is presented that can account for the observed transient uplift and is consistent with documented thermal regimes associated with underground nuclear tests conducted at the Nevada National Security Site (NNSS) (formerly the Nevada Test Site).

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

    SciTech Connect

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

    1991-07-01

    The COMMIX-1AR/P computer code 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 code to be applied to a wide range of problems involving both simple and complex geometrical arrangements. The basic equations, underlying assumptions, and solution techniques are presented for the entire computer code, covering both old and new features. 37 refs., 18 figs., 17 tabs.

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

    SciTech Connect

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

    1992-09-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    1991-07-01

    The COMMIX-1AR/P computer code 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 code to be applied to a wide range of problems involving both simple and complex geometrical arrangements. The basic equations, underlying assumptions, and solution techniques are presented for the entire computer code, covering both old and new features.

  14. Photo-induced current transient spectroscopy of defects in single crystals of synthetic diamond

    NASA Astrophysics Data System (ADS)

    Odrinskii, A. P.; Kazyuchits, N. M.; Makarenko, L. F.

    2015-11-01

    The kinetics of photocurrent relaxation in synthetic diamond single crystals with an electrical resistivity of 1014 ? cm in the temperature range of 440-550 K has been investigated. It has been found that there are two processes of thermal emission of charge carriers, which are detected simultaneously. The suppression of the contribution to the relaxation from one of the processes with an increase in the temperature has been interpreted as the formation of a coupling between the detected processes. The possibilities of the mutual influence between the processes of charge carrier emission have been discussed.

  15. A thermal formulation for single-wall quenching of transient laminar flames

    SciTech Connect

    Boust, B.; Sotton, J.; Labuda, S.A.; Bellenoue, M.

    2007-05-15

    Improving our knowledge of flame-wall interaction is of relevance to performing near-wall combustion calculations. Quenching distance is to be determined accordingly, as a major parameter of flame quenching. For this purpose, an equation describing the behavior of single-wall flame quenching has been derived from a simplified model of laminar flame-wall interaction. It allows evaluating quenching distance from wall heat flux and mixture properties; a significant advantage of this formula is the absence of any empirical coefficient. To assess its reliability, the results computed with this equation have been compared to experimental data concerning laminar flame-wall interaction. For this purpose, single-wall quenching parameters have been recorded in both head-on and sidewall configurations. Quenching distance and wall heat flux have been measured simultaneously, during the combustion of quiescent methane-air mixtures in a constant-volume vessel. Quenching distance is determined through direct visualization, whereas wall heat flux is processed from the time evolution of wall surface temperature. The equation has been verified over the pressure range 0.05-0.35 MPa in stoichiometric and lean mixtures. It shows good agreement with experimental data at first order, with less than 20% variation. (author)

  16. Cosmic Transients Test Einstein's Equivalence Principle out to GeV Energies

    NASA Astrophysics Data System (ADS)

    Gao, He; Wu, Xue-Feng; Mészáros, Peter

    2015-09-01

    The Einstein Equivalence Principle (EEP) can be probed with astrophysical sources emitting simultaneously different types of neutral particles, or particles with varying energies, by testing their time of flight through the same gravitational field. Here we use the time delays between correlated photons from cosmological transients to constrain the accuracy of the EEP. We take data from two gamma-ray bursts as an example and, as a lower limit to the theoretical time delays between different energies, we use delays arising from only the gravitational field of our own galaxy. We then show that the parameterized post-Newtonian parameter γ is the same for photons over energy ranges between eV and MeV and between MeV and GeV to a part in 10-7, which is at least one order of magnitude better than previous limits. Combining this bound on the wavelength dependence of γ with the absolute bound | γ -1| \\lt 0.3% from light-deflection measurements at optical (eV) wavelengths, we thus extend this absolute bound on γ to GeV energies.

  17. Quantitative EEG is an objective, sensitive, and reliable indicator of transient anesthetic effects during Wada tests.

    PubMed

    Tu, Bin; Assassi, Nadege J; Bazil, Carl W; Hamberger, Marla J; Hirsch, Lawrence J

    2015-04-01

    The intracarotid amobarbital or Wada procedure is a component of the presurgical evaluation for refractory epilepsy, during which monitoring the onset and offset of transient anesthetic effects is critical. In this study, the authors characterized changes of 8 quantitative measures during 26 Wada tests, which included alpha, beta, theta, and delta powers, alpha/delta power ratio, beta/delta power ratio, median amplitude-integrated EEG, and 90% spectral edge frequency (SEF90), and correlated them with contralateral hemiplegia. The authors found that on the side of injection, delta and theta powers, alpha/delta power ratio, beta/delta power ratio, and SEF90 peaked within 1 minute after injection of 70 to 150 mg amobarbital or 4 to 7 mg methohexital. When contralateral arm strength returned to 3/5, delta power and amplitude-integrated EEG decayed on average 24% and 19%, respectively, for amobarbital, similar to that of methohexital (27% and 18%). Because delta power resolution most closely mirrored that of the hemiplegia and amplitude-integrated EEG had the highest signal/noise ratio, these quantitative values appear to be the best measures for decay of anesthetic effects. Increase in alpha power persisted longest, and therefore may be the best measure of late residual anesthetic effects. PMID:25580802

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

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

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

    1983-01-01

    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.

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

    SciTech Connect

    Eisen, A.; Reynolds, G.T.

    1984-11-01

    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.

  1. Compendium of Test Results of Recent Single Event Effect Tests Conducted by the Jet Propulsion Laboratory

    NASA Technical Reports Server (NTRS)

    McClure, Steven S.; Allen, Gregory R.; Irom, Farokh; Scheick, Leif Z.; Adell, Philippe C.; Miyahira, Tetsuo F.

    2010-01-01

    This paper reports heavy ion and proton-induced single event effect (SEE) results from recent tests for a variety of microelectronic devices. The compendium covers devices tested over the last two years by the Jet Propulsion Laboratory.

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

    NASA Technical Reports Server (NTRS)

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

    1988-01-01

    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.

  3. A one-dimensional transient model of a single-stage, downward-firing entrained-flow gasifier

    SciTech Connect

    Kasule, J.; Turton, R.; Bhattacharyya, D.; Zitney, S.

    2012-01-01

    The integrated gasification combined cycle (IGCC) technology has emerged as an attractive alternative to conventional coal-fired power plant technology due to its higher efficiency and cleaner environmental performance especially with the option of CO{sub 2} capture and sequestration. The core unit of this technology is the gasifier whose optimal performance must be understood for efficient operation of IGCC power plants. This need has led a number of researchers to develop gasifier models of varying complexities. Whereas high-fidelity CFD models can accurately predict most key aspects of gasifier performance, they are computationally expensive and typically take hours to days to execute on high-performance computers. Therefore, faster one-dimensional (1D) partial differential equation (PDE)-based models are required for use in dynamic simulation studies, control system analysis, and training applications. A number of 1D gasifier models can be found in the literature, but most are steady-state and have limited application in the practical operation of the gasifier. As a result, 1D PDE-based dynamic models are needed to further study and predict gasifier performance under a wide variety of process conditions and disturbances. In the present study, a 1D transient model of a single-stage downward flow GE/Texaco-type gasifier has been developed. The model comprises mass, momentum and energy balances for the gas and solid phases. The model considers the initial gasification processes of water evaporation and coal devolatilization. In addition, the key heterogeneous and homogeneous chemical reactions have been modeled. The resulting time-dependent PDE model is solved using the well-known method of lines approach in Aspen Custom Modeler, whereby the PDEs are discretized in the spatial domain and the resulting differential algebraic equations (DAEs) are then solved to obtain the transient response. The transient response of various gasifier performance parameters to certain disturbances commonly encountered in the real world operation of commercial IGCC plants will be presented. These disturbances include ramp and step changes in input variables such as coal flow rate, oxygen-to-coal ratio and water-to-coal ratio, among others. Comparison of gasifier model predictions to available dynamic data will also be discussed.

  4. Visible Persistence of Single-Transient Random Dot Patterns: Spatial Parameters Affect the Duration of Fading Percepts

    PubMed Central

    Bruchmann, Maximilian; Thaler, Kathrin; Vorberg, Dirk

    2015-01-01

    Visible persistence refers to the continuation of visual perception after the physical termination of a stimulus. We studied an extreme case of visible persistence by presenting two matrices of randomly distributed black and white pixels in succession. On the transition from one matrix to the second, the luminance polarity of all pixels within a disk- or annulus-shaped area reversed, physically creating a single second-order transient signal. This transient signal produces the percept of a disk or an annulus with an abrupt onset and a gradual offset. To study the nature of this fading percept we varied spatial parameters, such as the inner and the outer diameter of annuli (Experiment I) and the radius and eccentricity of disks (Experiment III), and measured the duration of visible persistence by having subjects adjust the synchrony of the onset of a reference stimulus with the onset or the offset of the fading percept. We validated this method by comparing two modalities of the reference stimuli (Experiment I) and by comparing the judgments of fading percepts with the judgments of stimuli that actually fade in luminance contrast (Experiment II). The results show that (i) irrespective of the reference modality, participants are able to precisely judge the on- and the offsets of the fading percepts, (ii) auditory reference stimuli lead to higher visible persistence durations than visual ones, (iii) visible persistence duration increases with the thickness of annuli and the diameter of disks, but decreases with the diameter of annuli, irrespective of stimulus eccentricity. These effects cannot be explained by stimulus energy, which suggests that more complex processing mechanisms are involved. Seemingly contradictory effects of disk and annulus diameter can be unified by assuming an abstract filling-in mechanism that speeds up with the strength of the edge signal and takes more time the larger the stimulus area is. PMID:26348616

  5. Visible Persistence of Single-Transient Random Dot Patterns: Spatial Parameters Affect the Duration of Fading Percepts.

    PubMed

    Bruchmann, Maximilian; Thaler, Kathrin; Vorberg, Dirk

    2015-01-01

    Visible persistence refers to the continuation of visual perception after the physical termination of a stimulus. We studied an extreme case of visible persistence by presenting two matrices of randomly distributed black and white pixels in succession. On the transition from one matrix to the second, the luminance polarity of all pixels within a disk- or annulus-shaped area reversed, physically creating a single second-order transient signal. This transient signal produces the percept of a disk or an annulus with an abrupt onset and a gradual offset. To study the nature of this fading percept we varied spatial parameters, such as the inner and the outer diameter of annuli (Experiment I) and the radius and eccentricity of disks (Experiment III), and measured the duration of visible persistence by having subjects adjust the synchrony of the onset of a reference stimulus with the onset or the offset of the fading percept. We validated this method by comparing two modalities of the reference stimuli (Experiment I) and by comparing the judgments of fading percepts with the judgments of stimuli that actually fade in luminance contrast (Experiment II). The results show that (i) irrespective of the reference modality, participants are able to precisely judge the on- and the offsets of the fading percepts, (ii) auditory reference stimuli lead to higher visible persistence durations than visual ones, (iii) visible persistence duration increases with the thickness of annuli and the diameter of disks, but decreases with the diameter of annuli, irrespective of stimulus eccentricity. These effects cannot be explained by stimulus energy, which suggests that more complex processing mechanisms are involved. Seemingly contradictory effects of disk and annulus diameter can be unified by assuming an abstract filling-in mechanism that speeds up with the strength of the edge signal and takes more time the larger the stimulus area is. PMID:26348616

  6. Transient and steady-state tests of the space power research engine with resistive and motor loads

    NASA Astrophysics Data System (ADS)

    Rauch, Jeffrey S.; Kankam, M. David

    1995-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

    Rauch, Jeffrey S.; Kankam, M. David

    1995-01-01

    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.

  8. Sequential hydraulic tests for transient and highly permeable unconfined aquifer systems - model development and field-scale implementation

    NASA Astrophysics Data System (ADS)

    Ni, C.-F.; Huang, Y.-J.; Dong, J.-J.; Yeh, T.-C. J.

    2015-12-01

    The transient hydraulic tomography survey (THTS) is a conceptually improved technique that efficiently estimates detailed variations in aquifer parameters. Based on the concept of the THTS, we developed a geostatistical inverse model to characterize saturated hydraulic conductivity (K) and the specific yield (Sy) in transient and unconfined aquifer systems. In this study, a synthetic example was first used to assess the accuracy of the developed inverse model. Multiple random K and Sy realizations with different variances of natural logarithm of K (lnK) were generated and systematically compared to evaluate the effects of joint inversion on K estimations. The model was implemented in field-scale, cross-hole injection tests in a shallow and highly permeable unconfined aquifer near the middle reaches of the Wu River in central Taiwan. To assess the effect of constant head boundary conditions on the estimation results, two additional modeling domains were evaluated on the basis of the same field data from the injection tests. The results of the synthetic example showed that the proposed inverse model can effectively reproduce the predefined K patterns and magnitudes. However, slightly less detail was obtained for the Sy field based on the sampling data from sequential transient hydraulic stresses. The joint inversion by using transient head observations could slightly decrease the accuracy of K estimations. The model implementation for field-scale injection tests showed that the model can estimate K and Sy fields with detailed spatial variations. Estimation results showed a relatively homogeneous aquifer for the tested well field. Results based on the three modeling domains showed similar patterns and magnitudes of K and Sy near the well locations. These results indicated that the THTS is relatively insensitive to artificially drawn boundary conditions even under transient conditions.

  9. Solution-processed single-walled carbon nanotube field effect transistors and bootstrapped inverters for disintegratable, transient electronics

    SciTech Connect

    Jin, Sung Hun E-mail: jhl@snu.ac.kr Shin, Jongmin; Cho, In-Tak; Lee, Jong-Ho E-mail: jhl@snu.ac.kr; Han, Sang Youn; Lee, Dong Joon; Lee, Chi Hwan; Rogers, John A. E-mail: jhl@snu.ac.kr

    2014-07-07

    This paper presents materials, device designs, and physical/electrical characteristics of a form of nanotube electronics that is physically transient, in the sense that all constituent elements dissolve and/or disperse upon immersion into water. Studies of contact effects illustrate the ability to use water soluble metals such as magnesium for source/drain contacts in nanotube based field effect transistors. High mobilities and on/off ratios in transistors that use molybdenum, silicon nitride, and silicon oxide enable full swing characteristics for inverters at low voltages (∼5 V) and with high gains (∼30). Dissolution/disintegration tests of such systems on water soluble sheets of polyvinyl alcohol demonstrate physical transience within 30 min.

  10. Solution-processed single-walled carbon nanotube field effect transistors and bootstrapped inverters for disintegratable, transient electronics

    NASA Astrophysics Data System (ADS)

    Jin, Sung Hun; Shin, Jongmin; Cho, In-Tak; Han, Sang Youn; Lee, Dong Joon; Lee, Chi Hwan; Lee, Jong-Ho; Rogers, John A.

    2014-07-01

    This paper presents materials, device designs, and physical/electrical characteristics of a form of nanotube electronics that is physically transient, in the sense that all constituent elements dissolve and/or disperse upon immersion into water. Studies of contact effects illustrate the ability to use water soluble metals such as magnesium for source/drain contacts in nanotube based field effect transistors. High mobilities and on/off ratios in transistors that use molybdenum, silicon nitride, and silicon oxide enable full swing characteristics for inverters at low voltages (˜5 V) and with high gains (˜30). Dissolution/disintegration tests of such systems on water soluble sheets of polyvinyl alcohol demonstrate physical transience within 30 min.

  11. Efficient electromigration testing with a single current source

    NASA Astrophysics Data System (ADS)

    Kim, Choong-Un; Michael, N. L.; Jiang, Qing-Tang; Augur, Rod

    2001-10-01

    This article introduces a simple and effective technique for conducting electromigration testing of a number of samples using a single current source. It is based on a configuration where all samples are serially connected to a single current source, allowing them to be subjected to identical current conditions. In this design, each sample has a current bypass circuit, consisting essentially of a computer controlled shunt relay and a Zener diode, to enable continuation of testing without any interruption in the test current when samples fail. With this technique, a large number of samples can be tested with the same current and excellent current stability, making it suitable for both reliability assessment and scientific investigation of electromigration mechanisms. Initial results show high correlation with industry standard testing systems.

  12. SINGLE EVENT EFFECTS TEST FACILITY AT OAK RIDGE NATIONAL LABORATORY

    SciTech Connect

    Riemer, Bernie; Gallmeier, Franz X; Dominik, Laura J

    2015-01-01

    Increasing use of microelectronics of ever diminishing feature size in avionics systems has led to a growing Single Event Effects (SEE) susceptibility arising from the highly ionizing interactions of cosmic rays and solar particles. Single event effects caused by atmospheric radiation have been recognized in recent years as a design issue for avionics equipment and systems. To ensure a system meets all its safety and reliability requirements, SEE induced upsets and potential system failures need to be considered, including testing of the components and systems in a neutron beam. Testing of ICs and systems for use in radiation environments requires the utilization of highly advanced laboratory facilities that can run evaluations on microcircuits for the effects of radiation. This paper provides a background of the atmospheric radiation phenomenon and the resulting single event effects, including single event upset (SEU) and latch up conditions. A study investigating requirements for future single event effect irradiation test facilities and developing options at the Spallation Neutron Source (SNS) is summarized. The relatively new SNS with its 1.0 GeV proton beam, typical operation of 5000 h per year, expertise in spallation neutron sources, user program infrastructure, and decades of useful life ahead is well suited for hosting a world-class SEE test facility in North America. Emphasis was put on testing of large avionics systems while still providing tunable high flux irradiation conditions for component tests. Makers of ground-based systems would also be served well by these facilities. Three options are described; the most capable, flexible, and highest-test-capacity option is a new stand-alone target station using about one kW of proton beam power on a gas-cooled tungsten target, with dual test enclosures. Less expensive options are also described.

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

    SciTech Connect

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

    1994-12-31

    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.

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

    DOEpatents

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

    1997-09-30

    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.

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

    DOEpatents

    Kimbrough, Joseph Robert; Colella, Nicholas John

    1997-01-01

    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.

  16. Comparative research on “high currents” induced by single event latch-up and transient-induced latch-up

    NASA Astrophysics Data System (ADS)

    Chen, Rui; Han, Jian-Wei; Zheng, Han-Sheng; Yu, Yong-Tao; Shangguang, Shi-Peng; Feng, Guo-Qiang; Ma, Ying-Qi

    2015-04-01

    By using the pulsed laser single event effect facility and electro-static discharge (ESD) test system, the characteristics of the “high current”, relation with external stimulus and relevance to impacted modes of single event latch-up (SEL) and transient-induced latch-up (TLU) are studied, respectively, for a 12-bit complementary metal-oxide semiconductor (CMOS) analog-to-digital converter. Furthermore, the sameness and difference in physical mechanism between “high current” induced by SEL and that by TLU are disclosed in this paper. The results show that the minority carrier diffusion in the PNPN structure of the CMOS device which initiates the active parasitic NPN and PNP transistors is the common reason for the “high current” induced by SEL and for that by TLU. However, for SEL, the minority carrier diffusion is induced by the ionizing radiation, and an underdamped sinusoidal voltage on the supply node (the ground node) is the cause of the minority carrier diffusion for TLU. Project supported by the National Natural Science Foundation of China (Grant No. 41304148).

  17. Noninvasive testing of solenoid-operated valves using transient current signature analysis

    SciTech Connect

    Blakeman, E.D.; Kryter, R.C.

    1997-03-01

    A methodology has been developed for in situ diagnostic testing of dc-actuated solenoid-operated valves (SOVs) by analysis of the characteristics of the transient current waveform accompanying valve actuation. This waveform, which is used to identify abnormal operation, is obtained inductively by a small split-core current transformer clamped around one of the valve`s solenoid leads. The digitized waveforms are subsequently compared with similar waveforms obtained when the valve was known to be operating normally, and the results used to detect faulty valve operation. This methodology is noninvasive because direct access to the SOV is not required; also, the current transformer has negligible effect on the solenoid current and does not require the lifting of any electrical leads. Analysis is performed by first extracting various waveform features. A subset of these features is examined by diagnostic algorithms, tuned to identify faults for that valve type, that compare the features with those obtained from a previously acquired waveform for the particular valve under examination. Two methods of analysis have been examined. One utilizes fuzzy logic in an expert system diagnostic. The other performs pattern recognition using an artificial neural network approach. The overall analysis is robust in that it can deal with minor deviations of the waveform shape experienced during repeated operation of a normal valve while successfully identifying abnormal valve operation. In the present application, analysis has been specialized to SOVs used on space-based systems; however, the methodology has sufficient flexibility to be applicable to a wide variety of valves and other industrial electrically controlled components.

  18. Effect on the indo-1 transient of applying Ca2+ channel blocker for a single beat in voltage-clamped guinea-pig cardiac myocytes.

    PubMed Central

    Levi, A J; Li, J; Spitzer, K W; Bridge, J H

    1996-01-01

    1. We used rapid solution changes to investigate the mechanisms which trigger Ca2+ release from the sarcoplasmic reticulum (SR) in guinea-pig ventricular myocytes. We patch-clamped myocytes at 36 degrees C and used indo-1 to monitor intracellular Ca2+. Before each test pulse, we established a standard level of SR Ca2+ load by applying a train of conditioning pulses. 2. We switched rapidly to 32 microM nifedipine (an L-type Ca2+ current (ICa,L) blocker) 8 s before a test pulse, and just after applying nifedipine we applied a ramp depolarization to pre-block Ca2+ channels. We found that ICa,L elicited by the following test pulse was inhibited almost completely (98-99% inhibition). 3. The indo-1 transient elicited by an 800 ms depolarizing pulse showed a rapid initial rise which was inhibited by ryanodine-thapsigargin. This indicated that the rapid rise was due to Ca2+ release from the SR, and therefore provides an index of SR Ca2+ release. 4. In cells dialysed internally with 10 mM Na(+)-containing solution, nifedipine application before a +10 mV test pulse blocked 62% of the rapid initial phase of the indo-1 transient. Calibration curves of indo-1 for intracellular Ca2+ (using a KD of indo-1 for Ca2+ of either 250 or 850 nM, the reported range) indicated that between 67 and 76% of the Ca2+i transient was inhibited by nifedipine. Thus, in cells dialysed with 10 mM Na+ and depolarized to +10 mV, and in the absence of ICa,L, this suggests that another trigger mechanism for SR release is able to trigger between 33 and 24% of the Ca2+i transient. 5. For a given dialysing Na+ concentration, the fraction of indo-1 transient which was inhibited by nifedipine decreased as test potential became more positive. In cells dialysed with 10 mM Na+ and pulsed to +110 mV, 24% of the rapid phase of the indo-1 transient was inhibited by nifedipine (equivalent to between 27 and 37% of the Ca2+i transient). 6. For a given test potential, the fraction of the indo-1 transient which was inhibited by nifedipine decreased as dialysing Na+ concentration increased. In cells dialysed with Na(+)-free solution and pulsed to +10 mV, 84% of the indo-1 transient was inhibited by nifedipine (equivalent to between 88 and 91% of the Ca2+i transient). In contrast, in cells dialysed with 20 mM Na+ and pulsed to +10 mV, 41% of the indo-1 transient was inhibited by nifedipine (equivalent to between 47 and 57% of the Ca2+i transient). 7. Dialysing cells with different Na+ concentrations could lead to a different SR Ca2+ content. We therefore manipulated the conditioning train before each test pulse to change the extent of SR loading. For each dialysing Na+ concentration, we found no change in the degree to which nifedipine blocked the indo-1 transient when SR content was either increased or decreased. 8. The results support the idea that both ICa, L and a second mechanism are able to trigger SR release and the resulting Ca2+i transient. When ICa, L was blocked with nifedipine, the fraction of Ca2+i transient which remained increased with more positive test potential and higher internal Na+. This is consistent with the hypothesis that the second SR trigger mechanism is Ca2+ entry via reverse Na(+)-Ca2+ exchange, elicited by a step change in membrane potential. PMID:8865064

  19. Randomization Regression Tests for Single-Subject Data.

    ERIC Educational Resources Information Center

    Aaron, Bruce C.; Kromrey, Jeffrey D.

    In a Monte Carlo analysis of single-subject data, Type I and Type II error rates were compared for various statistical tests of the significance of treatment effects. Data for 5,000 subjects in each of 6 treatment effect size groups were computer simulated, and 2 types of treatment effects were simulated in the dependent variable during

  20. Single-Antigen Serological Testing for Bovine Tuberculosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibody responses are useful indicators of Mycobacterium bovis infection of cattle. Tests for serological responses often use panels of multiple M. bovis antigens as detection probes. This is recommended because responses to single antigens may be too variable for consistent diagnosis. However, the...

  1. Instrumented Taylor anvil-on-rod impact tests for validating applicability of standard strength models to transient deformation states

    NASA Astrophysics Data System (ADS)

    Eakins, D. E.; Thadhani, N. N.

    2006-10-01

    Instrumented Taylor anvil-on-rod impact tests have been conducted on oxygen-free electronic copper to validate the accuracy of current strength models for predicting transient states during dynamic deformation events. The experiments coupled the use of high-speed digital photography to record the transient deformation states and laser interferometry to monitor the sample back (free surface) velocity as a measure of the elastic/plastic wave propagation through the sample length. Numerical continuum dynamics simulations of the impact and plastic wave propagation employing the Johnson-Cook [Proceedings of the Seventh International Symposium on Ballistics, 1983, The Netherlands (Am. Def. Prep. Assoc. (ADPA)), pp. 541-547], Zerilli-Armstrong [J. Appl. Phys. C1, 1816 (1987)], and Steinberg-Guinan [J. Appl. Phys. 51, 1498 (1980)] constitutive equations were used to generate transient deformation profiles and the free surface velocity traces. While these simulations showed good correlation with the measured free surface velocity traces and the final deformed sample shape, varying degrees of deviations were observed between the photographed and calculated specimen profiles at intermediate deformation states. The results illustrate the usefulness of the instrumented Taylor anvil-on-rod impact technique for validating constitutive equations that can describe the path-dependent deformation response and can therefore predict the transient and final deformation states.

  2. A rare variant association test based on combinations of single-variant tests.

    PubMed

    Sha, Qiuying; Zhang, Shuanglin

    2014-09-01

    Next generation sequencing technologies make direct testing rare variant associations possible. However, the development of powerful statistical methods for rare variant association studies is still underway. Most of existing methods are burden and quadratic tests. Recent studies show that the performance of each of burden and quadratic tests depends strongly upon the underlying assumption and no test demonstrates consistently acceptable power. Thus, combined tests by combining information from the burden and quadratic tests have been proposed recently. However, results from recent studies (including this study) show that there exist tests that can outperform both burden and quadratic tests. In this article, we propose three classes of tests that include tests outperforming both burden and quadratic tests. Then, we propose the optimal combination of single-variant tests (OCST) by combining information from tests of the three classes. We use extensive simulation studies to compare the performance of OCST with that of burden, quadratic and optimal single-variant tests. Our results show that OCST either is the most powerful test or has similar power with the most powerful test. We also compare the performance of OCST with that of the two existing combined tests. Our results show that OCST has better power than the two combined tests. PMID:25065727

  3. A Rare Variant Association Test Based on Combinations of Single-Variant Tests

    PubMed Central

    Sha, Qiuying; Zhang, Shuanglin

    2014-01-01

    Next generation sequencing technologies make directly testing rare variant associations possible. However, the development of powerful statistical methods for rare variant association studies is still underway. Most of existing methods are burden and quadratic tests. Recent studies show that the performance of each of burden and quadratic tests depends strongly upon the underlying assumption and no test demonstrates consistently acceptable power. Thus, combined tests by combining information from the burden and quadratic tests have been proposed recently. However, results from recent studies (including this study) show that there exist tests that can outperform both burden and quadratic tests. In this article, we propose three classes of tests that include tests outperforming both burden and quadratic tests. Then, we propose the optimal combination of single-variant tests (OCST) by combining information from tests of the three classes. We use extensive simulation studies to compare the performance of OCST with that of burden, quadratic and optimal single-variant tests. Our results show that OCST either is the most powerful test or has similar power with the most powerful test. We also compare the performance of OCST with that of the two existing combined tests. Our results show that OCST has better power than the two combined tests. PMID:25065727

  4. Outbreak of Transient Conversions of the QuantiFERON-TB Gold In-Tube Test in Laboratory Health Care Worker Screenings

    PubMed Central

    Peracchi, Marta; Zorzi, Diego; Fiorio, Silvia; Fallico, Loredana; Pal, Giorgio

    2012-01-01

    Gamma interferon release assays were recently introduced in health care worker (HCWs) screenings for tuberculosis surveillance. In longitudinal surveys, conversions and reversions are seen, and yet whether these changes are unspecific or are an expression of new infections and microbial clearance remains unclear. In order to further elucidate these changes, we analyzed an outbreak of 15 transient conversions in 53 HCWs who operate in the same laboratory and handle specimens potentially containing Mycobacterium tuberculosis who underwent screening by the QuantiFERON-TB Gold In-Tube (QFT-GIT) test between 11 May and 30 June 2010: 15/46 (33%) negative HCWs showed a conversion and then reverted after 7 to 107 days. To validate these results, an evaluation of methodological procedures and test reliability, as well as an analysis of results obtained during the same period and processed by the same laboratory, was carried out. For the latter purpose, QFT-GIT results determined for 78 ward HCWs who underwent screening during the same period and were employed in departments with at least 3 infectious tuberculosis patients per year or had cared for an infectious patient without airborne precautions were analyzed with the following results: 6/63 (9%) HCWs with negative results in 3 different departments showed transient conversion (P = 0.002; odds ratio, 4.60; 95% confidence interval, 1.62 to 13.04). A retrospective survey of in-house biosafety practices led to determination of a single exposure factor within the laboratory. These data emphasize the validity of the hypothesis that a transient conversion demonstrates the presence of a real tubercular infection and could be an important indicator for occupational biosafety concerns. They also confirm that subjects with recent conversion should be retested before chest radiography and chemotherapy is offered. PMID:22518010

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

    SciTech Connect

    Kelly, John E.; Wright, Steven Alan; Tikare, Veena; MacLean, Heather J.; Parma, Edward J., Jr.; Peters, Curtis D.; Vernon, Milton E.; Pickard, Paul S.

    2007-10-01

    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.

  6. FOREVER ALONE? TESTING SINGLE ECCENTRIC PLANETARY SYSTEMS FOR MULTIPLE COMPANIONS

    SciTech Connect

    Wittenmyer, Robert A.; Horner, Jonathan; Tinney, C. G.; Bailey, J.; Salter, G. S.; Wright, D.; Wang Songhu; Zhou Jilin; Butler, R. P.; Jones, H. R. A.; O'Toole, S. J.; Carter, B. D.

    2013-09-15

    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.

  7. Analysis of BCL transient ECC-bypass test with TRAC-PD2/MOD1 code. [PWR

    SciTech Connect

    Slovik, G.; Saha, P.

    1982-01-01

    As part of the independent assessment of the TRAC-PD2/MOD1 code, a calculation for the Battelle Columbus Laboratories (BCL) transient Emergency Core Cooling (ECC) bypass test was performed. The purpose of this calculation was to assess the code's capability to predict the lower plenum refill rate after the initiation of ECC water injection during a postulated large break LOCA in a PWR system. BCL conducted several ECC bypass tests in their 2/15th-scale model of a typical pressurized water reactor vessel.

  8. Transient stress intensity factors for edge and corner cracks in quench-test specimens

    NASA Technical Reports Server (NTRS)

    Emery, A. F.; Kobayashi, A. S.

    1980-01-01

    The transient temperature and stress fields in a quenched rectangular bar were computed and used to determine the stress intensity factors for midside and corner-edge cracks. The stress intensity factors, KI, are presented as a function of time, flaw size, and aspect ratio. The variations of KI along the crack edge are given and the self-limiting growth of the crack depth is discussed in relation to the nonlimited surface growth.

  9. Single-qubit tests of Bell-like inequalities

    NASA Astrophysics Data System (ADS)

    de Zela, F.

    2007-10-01

    This paper discusses some tests of Bell-like inequalities not requiring entangled states. The proposed tests are based on consecutive measurements on a single qubit. Available hidden-variable models for a single qubit [see, e.g., J. S. Bell, Rev. Mod. Phys. 38, 447 (1966)] reproduce the predictions of quantum mechanics and hence violate the Bell-like inequalities addressed in this paper. It is shown how this fact is connected with the state collapse and with its random nature. Thus, it becomes possible to test truly realistic and deterministic hidden-variable models. In this way, it can be shown that a hidden-variable model should entail at least one of the following features: (i) nonlocality, (ii) contextuality, or (iii) discontinuous measurement-dependent probability functions. The last two features are put to the test with the experiments proposed in this paper. A hidden-variable model that is noncontextual and deterministic would be at variance with some predictions of quantum mechanics. Furthermore, the proposed tests are more likely to be loophole-free, as compared to former ones.

  10. Single-qubit tests of Bell-like inequalities

    SciTech Connect

    Zela, F. de

    2007-10-15

    This paper discusses some tests of Bell-like inequalities not requiring entangled states. The proposed tests are based on consecutive measurements on a single qubit. Available hidden-variable models for a single qubit [see, e.g., J. S. Bell, Rev. Mod. Phys. 38, 447 (1966)] reproduce the predictions of quantum mechanics and hence violate the Bell-like inequalities addressed in this paper. It is shown how this fact is connected with the state 'collapse' and with its random nature. Thus, it becomes possible to test truly realistic and deterministic hidden-variable models. In this way, it can be shown that a hidden-variable model should entail at least one of the following features: (i) nonlocality, (ii) contextuality, or (iii) discontinuous measurement-dependent probability functions. The last two features are put to the test with the experiments proposed in this paper. A hidden-variable model that is noncontextual and deterministic would be at variance with some predictions of quantum mechanics. Furthermore, the proposed tests are more likely to be loophole-free, as compared to former ones.

  11. Quick Look Report for Semiscale MOD-2C Test S-FS-6. [Simulating PWR transient from SG line break

    SciTech Connect

    Boucher, T.J.; Hall, D.G.

    1985-09-01

    Results of a preliminary analysis of the third test performed in the Semiscale MOD-2C Steam Generator Feedwater and Steam Line Break (FS) experiment series are presented. Test S-FS-6 simulated a pressurized water reactor transient initiated by a 100% break in a steam generator bottom feedwater line downstream of the check valve. With the exception of primary pressure, the initial conditions represented the initial conditions used for the C-E System 80 Final Safety Analysis Report (FSAR) Appendix 15B calculations. The transient included an initial 600s period in which only automatic plant protection systems responded to the initiating event. This period was followed by a series of operator actions necessary to stabilize the plant and a subsequent operator controlled natural circulation cooldown and depressurization with upper head void collapse method investigations. The test results provided a measured evaluation of the effectiveness of the automatic responses in minimizing primary system overpressurization and operator actions in stabilizing and recovering the plant. Test data also provided a basis for comparison with other tests in the series of the effects of break size on primary overpressurization and primary-to-secondary heat transfer.

  12. Coincident steam generator tube rupture and stuck-open safety relief valve carryover tests: MB-2 steam generator transient response test program

    SciTech Connect

    Garbett, K; Mendler, O J; Gardner, G C; Garnsey, R; Young, M Y

    1987-03-01

    In PWR steam generator tube rupture (SGTR) faults, a direct pathway for the release of radioactive fission products can exist if there is a coincident stuck-open safety relief valve (SORV) or if the safety relief valve is cycled. In addition to the release of fission products from the bulk steam generator water by moisture carryover, there exists the possibility that some primary coolant may be released without having first mixed with the bulk water - a process called primary coolant bypassing. The MB-2 Phase II test program was designed specifically to identify the processes for droplet carryover during SGTR faults and to provide data of sufficient accuracy for use in developing physical models and computer codes to describe activity release. The test program consisted of sixteen separate tests designed to cover a range of steady-state and transient fault conditions. These included a full SGTR/SORV transient simulation, two SGTR overfill tests, ten steady-state SGTR tests at water levels ranging from very low levels in the bundle up to those when the dryer was flooded, and three moisture carryover tests without SGTR. In these tests the influence of break location and the effect of bypassing the dryer were also studied. In a final test the behavior with respect to aerosol particles in a dry steam generator, appropriate to a severe accident fault, was investigated.

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

    NASA Astrophysics Data System (ADS)

    Sguera, V.

    2013-06-01

    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.

  14. Test aspect of single stage to orbit systems

    NASA Astrophysics Data System (ADS)

    Gaubatz, William A.; Nowlan, Daniel R.; Maras, Mathew G.; Copper, John A.; Coleman, Kate A.

    1995-03-01

    The McDonnell Douglas Delta Clipper Team recently completed the initial flight testing of a one third scale version of an operational single stage to orbit vehicle. The Delta Clipper Experimental, DC-X, is a 14 m tall, totally reusable, liquid hydrogen/liquid oxygen fueled test vehicle powered by four P&W RL-lOAS rocket engines. It has totally autonomous on board flight control and mission control systems; flight test mission requirements are simply added through software to the mission controller. The DC X is designed to explore and validate the low speed flight qualities of a vertical take-off and vertical landing spacecraft and its flight characteristics closely duplicate those predicted for the full scale DC-1 vehicle. The DC-1 vehicle would be capable of routinely flying people and/or cargo to and from space and would have a lift capacity for carrying 12 metric tons to low earth orbit.

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

    SciTech Connect

    Brenda R. Pace; Julie B. Williams

    2013-11-01

    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.

  16. Transient Plume Model Testing Using LADEE Spacecraft Attitude Control System Operations

    NASA Technical Reports Server (NTRS)

    Woronowicz, Michael

    2011-01-01

    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

  17. Constitutive modeling of superalloy single crystals with verification testing

    NASA Technical Reports Server (NTRS)

    Jordan, Eric; Walker, Kevin P.

    1985-01-01

    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.

  18. Vectoring Single Expansion Ramp Nozzle (VSERN) static model test program

    NASA Technical Reports Server (NTRS)

    Eames, D. J. H.; Mason, M. L.

    1988-01-01

    A variable throat-area, side-vectoring single expansion ramp nozzle (VSERN) concept's internal performance characteristics are studied with a view to controlling the bypass flow of an unmixed turbofan engine. Static tests have been conducted on VSERN at NASA-Langley using a variety of parametric models giving attention to the effects of upstream bend angle, ramp geometry, area ratio, and nozzle pressure ratio on static thrust and flow performance. Advantages of VSERN over the conventional vectoring axisymmetric convergent side-nozzles typified by those of the Harrier's Pegasus engine.

  19. Design, fabrication and testing of single spoke resonators at Fermilab

    SciTech Connect

    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

    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.

  20. Engineering test results for the Moog Single Line Disconnect

    NASA Technical Reports Server (NTRS)

    Glubke, Scott E.

    1990-01-01

    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.

  1. Single Foraminiferal Test Chemistry From Laser Ablation Icp-ms

    NASA Astrophysics Data System (ADS)

    Reichart, G. J.; Mason, P.; Jorissen, F.; Anschutz, P.

    Physical and chemical conditions in the marine environment control trace element incorporation into biogenic carbonates. This makes it possible to use trace element concentrations in calcareous foraminiferal tests to reconstruct past changes in these conditions over time. We applied Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) as a new and precise technique for measuring trace el- ements in benthic foraminifera (Hoeglundina elegans). With this technique trace ele- ment concentrations can be measured accurately without the standard elaborate clean- ing techniques. Through spatially resolved analyses contaminating coatings are easily recognized and can be excluded from further analyses. Application of this new tech- nique allowed for the first time to calibrate the inbuilt of trace elements in single tests of living benthic foraminifera to ambient seawater temperature, nutrient content and redox conditions.

  2. Implementation and Testing of the First Prompt Search for Gravitational Wave Transients with Electromagnetic Counterparts

    NASA Technical Reports Server (NTRS)

    Abadie, J.; Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M.; Accadia, T.; Acernese, F.; Adams, C.; Adhikari, R.; Affeldt, C.; Agathos, M.; Ajith, P.; Allen, B.; Allen, G. S.; Ceron, E. Amador; Amariutei, D.; Amin, R. S.; Anderson, S. B.; Anderson, W. G.; Araya, M. C.; Aston, S. M.; Astone, P.; Atkinson, D.; Aufmuth, P.; Blackburn, L.

    2012-01-01

    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 MilkyWay 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.

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

    NASA Technical Reports Server (NTRS)

    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

    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.

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

    NASA Astrophysics Data System (ADS)

    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.; Ju, L.; Kalmus, P.; Kalogera, V.; Kamaretsos, I.; Kandhasamy, S.; Kang, G.; Kanner, J. B.; Katsavounidis, E.; Katzman, W.; Kaufer, H.; Kawabe, K.; Kawamura, S.; Kawazoe, F.; Kells, W.; Keppel, D. G.; Keresztes, Z.; Khalaidovski, A.; Khalili, F. Y.; Khazanov, E. A.; Kim, B.; Kim, C.; Kim, D.; Kim, H.; Kim, K.; Kim, N.; Kim, Y.-M.; King, P. J.; Kinsey, M.; Kinzel, D. L.; Kissel, J. S.; Klimenko, S.; Kokeyama, K.; Kondrashov, V.; Kopparapu, R.; Koranda, S.; Korth, W. Z.; Kowalska, I.; Kozak, D.; Kringel, V.; Krishnamurthy, S.; Krishnan, B.; Krâ´Olak, A.; Kuehn, G.; Kumar, R.; Kwee, P.; Laas-Bourez, M.; Lam, P. K.; Landry, M.; Lang, M.; Lantz, B.; Lastzka, N.; Lawrie, C.; Lazzarini, A.; Leaci, P.; Lee, C. H.; Lee, H. M.; Leindecker, N.; Leong, J. R.; Leonor, I.; Leroy, N.; Letendre, N.; Li, J.; Li, T. G. F.; Liguori, N.; Lindquist, P. E.; Lockerbie, N. A.; Lodhia, D.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Luan, J.; Lubinski, M.; Lück, H.; Lundgren, A. P.; MacDonald, E.; Machenschalk, B.; Macinnis, M.; MacLeod, D. M.; Mageswaran, M.; Mailand, K.; Majorana, E.; Maksimovic, I.; Man, N.; Mandel, I.; Mandic, V.; Mantovani, M.; Marandi, A.; Marchesoni, F.; Marion, F.; Márka, S.; Márka, Z.; Markosyan, A.; Maros, E.; Marque, J.; Martelli, F.; Martin, I. W.; Martin, R. M.; Marx, J. N.; Mason, K.; Masserot, A.; Matichard, F.; Matone, L.; Matzner, R. A.; Mavalvala, N.; Mazzolo, G.; McCarthy, R.; McClelland, D. E.; McDaniel, P.; McGuire, S. C.; McIntyre, G.; McIver, J.; McKechan, D. J. A.; Meadors, G. D.; Mehmet, M.; Meier, T.; Melatos, A.; Melissinos, A. C.; Mendell, G.; Menendez, D.; Mercer, R. A.; Meshkov, S.; Messenger, C.; Meyer, M. S.; Miao, H.; Michel, C.; Milano, L.; Miller, J.; Minenkov, Y.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Miyakawa, O.; Moe, B.; Moesta, P.; Mohan, M.; Mohanty, S. D.; Mohapatra, S. R. P.; Moraru, D.; Moreno, G.; Morgado, N.; Morgia, A.; Mori, T.; Mosca, S.; Mossavi, K.; Mours, B.; Mow-Lowry, C. M.; Mueller, C. L.; Mueller, G.; Mukherjee, S.; Mullavey, A.; Müller-Ebhardt, H.; Munch, J.; Murphy, D.; Murray, P. G.; Mytidis, A.; Nash, T.; Naticchioni, L.; Nawrodt, R.; Necula, V.; Nelson, J.; Newton, G.; Nishizawa, A.; Nocera, F.; Nolting, D.; Nuttall, L.; Ochsner, E.; O'Dell, J.; Oelker, E.; Ogin, G. H.; Oh, J. J.; Oh, S. H.; Oldenburg, R. G.; O'Reilly, B.; O'Shaughnessy, R.; Osthelder, C.; Ott, C. D.; Ottaway, D. J.; Ottens, R. S.; Overmier, H.; Owen, B. J.; Page, A.; Pagliaroli, G.; Palladino, L.; Palomba, C.; Pan, Y.; Pankow, C.; Paoletti, F.; Papa, M. A.; Parisi, M.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patel, P.; Pedraza, M.; Peiris, P.; Pekowsky, L.; Penn, S.; Peralta, C.; Perreca, A.; Persichetti, G.; Phelps, M.; Pickenpack, M.; Piergiovanni, F.; Pietka, M.; Pinard, L.; Pinto, I. M.; Pitkin, M.; Pletsch, H. J.; Plissi, M. V.; Poggiani, R.; Pöld, J.; Postiglione, F.; Prato, M.; Predoi, V.; Price, L. R.; Prijatelj, M.; Principe, M.; Privitera, S.; Prix, R.; Prodi, G. A.; Prokhorov, L.; Puncken, O.; Punturo, M.; Puppo, P.; Quetschke, V.; Raab, F. J.; Rabeling, D. S.; Rácz, I.; Radkins, H.; Raffai, P.; Rakhmanov, M.; Ramet, C. R.; Rankins, B.; Rapagnani, P.; Rapoport, S.; Raymond, V.; Re, V.; Redwine, K.; Reed, C. M.; Reed, T.; Regimbau, T.; Reid, S.; Reitze, D. H.; Ricci, F.; Riesen, R.; Riles, K.; Robertson, N. A.; Robinet, F.; Robinson, C.; Robinson, E. L.; Rocchi, A.; Roddy, S.; Rodriguez, C.; Rodruck, M.; Rolland, L.; Rollins, J.; Romano, J. D.; Romano, R.; Romie, J. H.; Rosińska, D.; Röver, C.; Rowan, S.; Rüdiger, A.; Ruggi, P.; Ryan, K.; Ryll, H.; Sainathan, P.; Sakosky, M.; Salemi, F.; Samblowski, A.; Sammut, L.; Sancho de La Jordana, L.; Sandberg, V.; Sankar, S.; Sannibale, V.; Santamaría, L.; Santiago-Prieto, I.; Santostasi, G.; Sassolas, B.; Sathyaprakash, B. S.; Sato, S.; Saulson, P. R.; Savage, R. L.; Schilling, R.; Schlamminger, S.; Schnabel, R.; Schofield, R. M. S.; Schulz, B.; Schutz, B. F.; Schwinberg, P.; Scott, J.; Scott, S. M.; Searle, A. C.; Seifert, F.; Sellers, D.; Sengupta, A. S.; Sentenac, D.; Sergeev, A.; Shaddock, D. A.; Shaltev, M.; Shapiro, B.; Shawhan, P.; Shoemaker, D. H.; Sibley, A.; Siemens, X.; Sigg, D.; Singer, A.; Singer, L.; Sintes, A. M.; Skelton, G.; Slagmolen, B. J. J.; Slutsky, J.; Smith, J. R.; Smith, M. R.; Smith, N. D.; Smith, R. J. E.; Somiya, K.; Sorazu, B.; Soto, J.; Speirits, F. C.; Sperandio, L.; Stefszky, M.; Stein, A. J.; Steinert, E.; Steinlechner, J.; Steinlechner, S.; Steplewski, S.; Stochino, A.; Stone, R.; Strain, K. A.; Strigin, S.; Stroeer, A. S.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Sung, M.; Susmithan, S.; Sutton, P. J.; Swinkels, B.; Tacca, M.; Taffarello, L.; Talukder, D.; Tanner, D. B.; Tarabrin, S. P.; Taylor, J. R.; Taylor, R.; Thomas, P.; Thorne, K. A.; Thorne, K. S.; Thrane, E.; Thüring, A.; Titsler, C.; Tokmakov, K. V.; Toncelli, A.; Tonelli, M.; Torre, O.; Torres, C.; Torrie, C. I.; Tournefier, E.; Travasso, F.; Traylor, G.; Trias, M.; Tseng, K.; Ugolini, D.; Urbanek, K.; Vahlbruch, H.; Vajente, G.; Vallisneri, M.; van den Brand, J. F. J.; van den Broeck, C.; van der Putten, S.; van Veggel, A. A.; Vass, S.; Vasuth, M.; Vaulin, R.; Vavoulidis, M.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P. J.; Veltkamp, C.; Verkindt, D.; Vetrano, F.; Viceré, A.; Villar, A. E.; Vinet, J.-Y.; Vitale, S.; Vitale, S.; Vocca, H.; Vorvick, C.; Vyatchanin, S. P.; Wade, A.; Waldman, S. J.; Wallace, L.; Wan, Y.; Wang, X.; Wang, Z.; Wanner, A.; Ward, R. L.; Was, M.; Wei, P.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Wen, L.; Wen, S.; Wessels, P.; West, M.; Westphal, T.; Wette, K.; Whelan, J. T.; Whitcomb, S. E.; White, D.; Whiting, B. F.; Wilkinson, C.; Willems, P. A.; Williams, H. R.; Williams, L.; Willke, B.; Winkelmann, L.; Winkler, W.; Wipf, C. C.; Wiseman, A. G.; Wittel, H.; Woan, G.; Wooley, R.; Worden, J.; Yablon, J.; Yakushin, I.; Yamamoto, H.; Yamamoto, K.; Yang, H.; Yeaton-Massey, D.; Yoshida, S.; Yu, P.; Yvert, M.; Zadroźny, A.; Zanolin, M.; Zendri, J.-P.; Zhang, F.; Zhang, L.; Zhang, W.; Zhang, Z.; Zhao, C.; Zotov, N.; Zucker, M. E.; Zweizig, J.; Akerlof, C.; Boer, M.; Fender, R.; Gehrels, N.; Klotz, A.; Ofek, E. O.; Smith, M.; Sokolowski, M.; Stappers, B. W.; Steele, I.; Swinbank, J.; Wijeres, R. A. M. J.

    2012-04-01

    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.

  5. M3B2 and M5B3 Formation in Diffusion-Affected Zone During Transient Liquid Phase Bonding Single-Crystal Superalloys

    NASA Astrophysics Data System (ADS)

    Sheng, Naicheng; Hu, Xiaobing; Liu, Jide; Jin, Tao; Sun, Xiaofeng; Hu, Zhuangqi

    2015-04-01

    Precipitates in the diffusion-affected zone (DAZ) during transient liquid phase bonding (TLP) single-crystal superalloys were observed and investigated. Small size and dendritic-shaped precipitates were identified to be M3B2 borides and intergrowth of M3B2/M5B3 borides. The orientation relationships among M3B2, M5B3, and matrix were determined using transmission electron microscope (TEM). Composition characteristics of these borides were also analyzed by TEM energy-dispersive spectrometer. Because this precipitating phenomenon deviates from the traditional parabolic transient liquid phase bonding model which assumed a precipitates free DAZ during TLP bonding, some correlations between the deviation of the isothermal solidification kinetics and these newly observed precipitating behaviors were discussed and rationalized when bonding the interlayer containing the high diffusivity melting point depressant elements and substrates of low solubility.

  6. Single Stage Contactor Testing Of The Next Generation Solvent Blend

    SciTech Connect

    Herman, D. T.; Peters, T. B.; Duignan, M. R.; Williams, M. R.; Poirier, M. R.; Brass, E. A.; Garrison, A. G.; Ketusky, E. T.

    2014-01-06

    The Modular Caustic Side Solvent Extraction (CSSX) Unit (MCU) facility at the Savannah River Site (SRS) is actively pursuing the transition from the current BOBCalixC6 based solvent to the Next Generation Solvent (NGS)-MCU solvent to increase the cesium decontamination factor. To support this integration of NGS into the MCU facility the Savannah River National Laboratory (SRNL) performed testing of a blend of the NGS (MaxCalix based solvent) with the current solvent (BOBCalixC6 based solvent) for the removal of cesium (Cs) from the liquid salt waste stream. This testing utilized a blend of BOBCalixC6 based solvent and the NGS with the new extractant, MaxCalix, as well as a new suppressor, tris(3,7dimethyloctyl) guanidine. Single stage tests were conducted using the full size V-05 and V-10 liquid-to-liquid centrifugal contactors installed at SRNL. These tests were designed to determine the mass transfer and hydraulic characteristics with the NGS solvent blended with the projected heel of the BOBCalixC6 based solvent that will exist in MCU at time of transition. The test program evaluated the amount of organic carryover and the droplet size of the organic carryover phases using several analytical methods. The results indicate that hydraulically, the NGS solvent performed hydraulically similar to the current solvent which was expected. For the organic carryover 93% of the solvent is predicted to be recovered from the stripping operation and 96% from the extraction operation. As for the mass transfer, the NGS solvent significantly improved the cesium DF by at least an order of magnitude when extrapolating the One-stage results to actual Seven-stage extraction operation with a stage efficiency of 95%.

  7. Single Component Sorption-Desorption Test Experimental Design Approach Discussions

    SciTech Connect

    Phil WInston

    2011-09-01

    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.

  8. Test of Single-Stage Axial-Flow Fan

    NASA Technical Reports Server (NTRS)

    Bell, E Barton

    1942-01-01

    A single-stage axial fan was built and tested in the shop of the propeller-research tunnel of the NACA. The fan comprised a simple 24-blade rotor having a diameter of 21 inches and a solidity of 0.86 and a set of 37 contravanes having a solidity of 1.33. The rotor was driven by a 25-horsepower motor capable of rotating at a speed of 3600 r.p.m. The fan was tested for volume, pressure, and efficiency over a range of delivery pressures and volumes for a wide range of contravane and blade-angle settings. The test results are presented in chart form in terms of nondimensional units in order that similar fans may be accurately designed with a minimum effort. The maximum efficiency (88 percent) was obtained by the fan at a blade angle of 30 degrees and a contravane angle of 70 degrees. An efficiency of 80 percent was obtained by the fan with the contravanes removed.

  9. Thermal Performance Testing of Single Channel GRCop-84 SLM Components

    NASA Technical Reports Server (NTRS)

    Garcia, Chance P.; Cross, Matthew

    2015-01-01

    The surface finish found on components manufactured by sinter laser manufacturing (SLM) is rougher (0.013 - 0.0006 inches) than parts made using traditional fabrication methods. Internal features and passages built into SLM components do not readily allow for roughness reduction processes. Alternatively, engineering literature suggests that the roughness of a surface can enhance thermal performance within a pressure drop regime. To further investigate the thermal performance of SLM fabricated pieces, several GRCop-84 SLM single channel components were tested using a thermal conduction rig at MSFC. A 20 kW power source running at 25% duty cycle and 25% power level applied heat to each component while varying water flow rates between 2.1 - 6.2 gallons/min (GPM) at a supply pressure of 500 to 750 psi. Each test was allowed to reach quasi-steady state conditions where pressure, temperature, and thermal imaging data were recorded. Presented in this work are the heat transfer responses compared to a traditional machined OHFC Copper test section. An analytical thermal model was constructed to anchor theoretical models with the empirical data.

  10. Differentiation of Performance-Limiting Voltage Transients during Nb3Sn Magnet Testing

    NASA Astrophysics Data System (ADS)

    Lietzke, A. F.; Mattafirri, S.; McInturff, A. D.; Nyman, M.; Dietderich, D. R.; Gourlay, S. A.; Sabbi, G. L.

    2006-03-01

    The Superconducting Magnet Group at Lawrence Berkeley National Laboratory has been developing high-field, brittle-superconductor, accelerator magnet technology for several years. While recent dramatic increases in Nb3Sn superconducting current density, (Jc = 3000 A/mm2 at 12 Tesla, 4.2 K) have facilitated the achievement of record peak dipole bore-fields (16 Tesla), the number and size of fast intra-coil flux-adjustments of the "flux-jump" variety have increased with the current density. In 2000, with state-of-the art (Jc = 2000 A/mm2 at 12 T) Nb3Sn conductor, the associated coil voltage transients were observed to be large enough to cause nuisance "quench-detector" magnet-protection false-alarms. Subsequent Jc increases have resulted in large enough flux-jumps to cause premature quenches in some magnets, at currents well below those predicted by their virgin strand superconducting "short-sample" measurements. This paper will examine various types of quench-onsets and their distinguishing characteristics. The associated observational techniques are briefly discussed.

  11. Barometric pressure transient testing: Analysis methods and solution uniqueness: Final report

    SciTech Connect

    Hanson, J.M.

    1987-10-01

    Analysis of barometric pressure transients has been shown to be a useful tool in identifying the permeability structure in porous and permeable subsurface formations. The basic approach used in this technique requires monitoring surface barometric pressure fluctuations and the subsurface response to the surface pressure variation at one or more sensor locations over a period of time. These data are then used in conjunction with a given model of the subsurface to extract best estimates of one or more of the model parameters. A number of non-ideal conditions may affect solution uniqueness. These include the existence of noise on the data, sparse subsurface instrumentation, using an incorrect hole-formation model to interpret the data, and the frequency content of the recorded barometric pressure data. All of the work directed toward describing solution uniqueness and parameter uncertainty is presented. Other topics include refinement of several existing formation models, addressing the possibility of extracting an impulse response function from the measured data so that some kind of ''type-curve'' analysis can be applied, and the usefulness of carrying out the analysis in the frequency-domain. 5 refs., 21 figs., 10 tabs.

  12. Testing the single degenerate channel for supernova Ia

    NASA Astrophysics Data System (ADS)

    Parsons, Steven

    2014-10-01

    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.

  13. Results of the latest transient well pressure tests at Cerro Prieto

    SciTech Connect

    Abril G, A.; Vargas G, C.

    1981-01-01

    The equipment used in the interference and two-rate flow tests carried out at the Cerro Prieto geothermal field during 1980 are described. The results of two interference tests are presented, one between wells M-110 and M-104, and the other between wells M-7 and Q-757. The data was interpreted using type curve matching analysis. Results of two-rate flow tests carried out in wells M-102 and M-7 are also discussed. A technique for making two-rate flow tests is proposed. This approach, which attempts to avoid the uncertainty of present flow-rate measurements, makes use of devices for direct measurements of separated water and steam. Conclusions based on the above interpretations and recommendations for future tests are presented.

  14. Geological Hypothesis Testing and Investigations of Coupling with Transient Electromagnetics (TEM)

    NASA Astrophysics Data System (ADS)

    Adams, A. C.; Moeller, M. M.; Snyder, E.; Workman, E. J.; Urquhart, S.; Bedrosian, P.; Pellerin, L.

    2014-12-01

    Transient electromagnetic (TEM) data were acquired in Borrego Canyon within the Santo Domingo Basin of the Rio Grande Rift, central New Mexico, during the 2014 Summer of Applied Geophysical Experience (SAGE) field program. TEM surveys were carried out in several regions both to investigate geologic structure and to illustrate the effects of coupling to anthropogenic structures. To determine an optimal survey configuration, 50, 100 and 200 m square transmitter loops were deployed; estimates of depth-of-investigation and logistical considerations determined that 50 m loops were sufficient for production-style measurements. A resistive (100s of ohm-m) layer was identified at a depth of 25-75 m at several locations, and interpreted as dismembered parts of one or more concealed volcanic flows, an interpretation consistent with Tertiary volcanic flows that cap the Santa Anna Mesa immediately to the south. TEM soundings were also made across an inferred fault to investigate whether fault offset is accompanied by lateral changes in electrical resistivity. Soundings within several hundred meters of the inferred fault strand were identical, indicating no resistivity contrast across the fault, and possibly an absence of recent activity. An old windmill and water tank, long-abandoned, offered an excellent laboratory to study the effect of coupling to metallic anthropogenic structures. The character of the measured data strongly suggests the water tank is in electrical contact with the earth (galvanic coupling), and an induced response was persistent to more than 1 second after current turn-off. Coupling effects could be identified at least 150 meters from the tank. Understanding the mechanism behind such coupling and the ability to identify coupled data are critical skills, as one-dimensional modeling of data is affected by such coupling producing artificial conductive layers at depth.

  15. The Mirrortron experiment: A proof of principle test for a method of generating high transient potentials

    SciTech Connect

    Douglass, S.R.

    1993-09-01

    The Mirrortron is a concept in which heavy ions are accelerated by a large local transient space potential that is produced in a hot electron plasma. The purpose of this experiment is to begin a proof of principle experiment to investigate the feasibility of producing this space potential and its associated electric field. If a large magnetic field is suddenly generated in a hot electron plasma with a loss-cone distribution, then potentials on the order of the electron temperature are expected. This potential lasts a few tens of nanoseconds. The investigation begins with a theoretical analysis of this phenomenon giving the space potential as a function of the applied magnetic field. The theory is further extended to cases of relativistic electron distributions. This is then followed by design work on a mirror confinement system for hot electrons. In this experiment a 50--100 keV electron temperature plasma is created with electron cyclotron resonance heating using two frequencies of relatively low microwave power. The microwaves are coupled to resonant frequencies of the vacuum chamber. The volume averaged plasma density is measured to be in the 10{sup 9} cm{sup {minus}3} range. A strap coil and a flat Blumlein transmission line pulse generator were developed to produce a 150 gauss field within 70 ns. The strap coil was placed at the midplane of the mirror field, where the field is 700 gauss. Based on theoretical estimates and computer simulations a 20 kV potential is expected. Measurement of this potential is derived from the modulation of the current of a monoenergetic electron beam after it passes through the high potential region. The variation in the beam energy allows bunching to occur in transit to the detector.

  16. A Randomized, Double-Blind, Single-Dose, Placebo-Controlled, Multicenter, Polysomnographic Study of Gabapentin in Transient Insomnia Induced by Sleep Phase Advance

    PubMed Central

    Rosenberg, Russell P.; Hull, Steven G.; Lankford, D. Alan; Mayleben, David W.; Seiden, David J.; Furey, Sandy A.; Jayawardena, Shyamalie; Roth, Thomas

    2014-01-01

    Study Objectives: To evaluate the effects of single doses of gabapentin 250 and 500 mg on polysomnographic (PSG) and participant-reported sleep measures in a 5-h phase advance insomnia model. Methods: Adults reporting occasional disturbed sleep received gabapentin 500 mg (n = 125), 250 mg (n = 125), or placebo (n = 127) 30 min prior to bedtime and were in bed from 17:00 to 01:00, ∼5 h before their habitual bedtime. Sleep was assessed by PSG, post-sleep questionnaire, and the Karolinska Sleep Diary (KSD). Next-day residual effects (Digit Symbol Substitution Test [DSST] and Stanford Sleepiness Scale [SSS]) and tolerability were assessed. Results: Demographics were comparable among groups. Among PSG endpoints, wake after sleep onset (primary endpoint) (135.7 [placebo], 100.7 [250 mg], and 73.2 [500 mg] min) was significantly lower and total sleep time (TST) (311.4, 356.5, and 378.7 min) significantly greater in both gabapentin groups versus placebo. Latency to persistent sleep was not significantly different among groups. Percent slow wave sleep (12.6%, 15.4%, and 17.0%, respectively) was significantly greater and percent stage 1 (15.1%, 11.8%, and 10.8%, respectively) significantly lower relative to placebo. Gabapentin was associated with significantly higher values of KSD Sleep Quality Index and reported TST versus placebo; no other reported outcomes were significant. Neither gabapentin dose produced evidence of next-day residual effects as measured by DSST and SSS. Adverse events were infrequent (< 5%). Conclusion: Participants with occasional disturbed sleep treated with gabapentin showed significantly longer sleep duration and greater depth (versus placebo) in response to a phase advance manipulation known to disrupt sleep maintenance. Citation: Rosenberg RP, Hull SG, Lankford DA, Mayleben DW, Seiden DJ, Furey SA, Jayawardena S, Roth T. A randomized, double-blind, single-dose, placebo-controlled, multicenter, polysomnographic study of gabapentin in transient insomnia induced by sleep phase advance. J Clin Sleep Med 2014;10(10):1093-1100. PMID:25317090

  17. Estimating transmissivity from single-well pumping tests in heterogeneous aquifers

    NASA Astrophysics Data System (ADS)

    Pechstein, Armin; Attinger, Sabine; Krieg, Ronald; Copty, Nadim K.

    2016-01-01

    Although aquifers are naturally heterogeneous, the interpretation of pumping tests is commonly performed under the assumption of aquifer homogeneity. This yields interpreted hydraulic parameters averaged over a domain of uncertain extent which disguises their relation to the underlying heterogeneity. In this study, we numerically investigate the sensitivity of the transient drawdown at the pumping well, to nonuniform distributions of transmissivity in confined aquifers. Frechet kernels and their time derivative are used to estimate two spatially averaged transmissivities, denoted the equivalent and interpreted transmissivity, Teq and Tin, respectively, for the case of single-well pumping tests. Interrelating Teq and Tin is achieved by modeling Tin in terms of a distance dependent, radially heterogeneous field. In weakly heterogeneous aquifers, Teq approximates TPW, the local transmissivity at the pumped well. With increasing degree of heterogeneity, Teq deviates from TPW as pumping propagates. Tin starts at TPW, approaching the spatial geometric mean of transmissivity during late pumping times. Limits of the proposed spatial weighting functions are investigated by treating the interpreted storativity, Sest, as an indicator for flow connectivity. It is shown numerically that the spatial weights for Teq and Tin agree well to the underlying heterogeneity if . Finally, implications for applying the concepts of Teq and Tin to heterogeneous domains, and, for real world applications are discussed. It is found that time-dependent spatial averages of Tin agree well with estimates of the interpreted transmissivity from the Continuous-Derivation method.

  18. 40 CFR 1048.510 - What transient duty cycles apply for laboratory testing?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, LARGE NONROAD SPARK-IGNITION ENGINES Test... cycle statistics and compare with the established criteria as specified in 40 CFR 1065.514 to...

  19. 40 CFR 1048.510 - What transient duty cycles apply for laboratory testing?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... cycle statistics and compare with the established criteria as specified in 40 CFR 1065.514 to confirm... operating before a test, use good engineering judgment to let the engine cool down enough so...

  20. Radiation tests for a single-GEM-loaded gaseous detector

    NASA Astrophysics Data System (ADS)

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

    2014-11-01

    We report on a systematic study of a single-gas-electron-multiplier (GEM)-loaded gaseous detector developed for precision measurements of high-energy particle beams and for dose verification in particle therapy. In the present study, a 256-channel prototype detector having an active area of 16 × 16 cm2 and operating using 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 X-rays with an intensity of about 5 × 106 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 a proper calibration to the channel responses of the measured beam-profile data. We conclude from the radiation tests that the detector developed in the present study will allow us to perform quality measurements of various high-energy particle beams and to apply the technology to dose-verification measurements in particle therapy.

  1. Single species aquatic toxicity testing for environmental regulation of chemicals. Proposal for a flexible testing approach

    SciTech Connect

    Kristensen, P.; Roghair, C.; Tyle, H.

    1995-12-31

    In a co-operation between Denmark and The Netherlands, a Detailed Review Paper on Aquatic Testing Methods for Pesticides and Industrial Chemicals has been elaborated for the consideration of the National Coordinators of the OECD Test Guideline Programme. The objective of the review is to identify the need for revision of existing OECD Test Guidelines and also to identify the need for elaboration of new guidelines. The background for the recommendations made is (1) a comprehensive review of more than 600 pelagic and benthic testing methods collected from national standardization organizations and from the scientific literature, (2) an evaluation of the methods based on a set of formalized evaluation criteria, (3) an identification of the present needs in national and international aquatic effects assessment schemes and (4) a proposed framework for future assessment of chemicals in specific types of aquatic environments. It is foreseen that future assessments (which go beyond the initial generic assessment) may be directed toward specific types of aquatic environments. The proposal for new testing methods has therefore been framed into five testing scenarios. Four testing scenarios for the benthic and pelagic compartments, respectively: cold freshwater environment, warm freshwater environment, cold marine environment and warm marine environment and a testing scenario for assessment of biological waste water treatment. The rational for the elaboration of single species testing scenarios will especially be addressed.

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

    NASA Technical Reports Server (NTRS)

    Wang, Ten-See; Dumas, Catherine

    1993-01-01

    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 employed for the spatial discretization, and a predictor, multiple corrector method is used for the temporal solution. Both engine start-up and shut-down processes were simulated. The elapse time is approximately five seconds for both cases. The computed results were animated and compared with the test. The images for the animation were created with PLOT3D and FAST and then animated with ABEKAS. The hysteresis effects, and the issues of free-shock separation, restricted-shock separation and the end-effects were addressed.

  3. Delayed emission of surface-generated trapped carriers in transient charge transport of single-crystal and polycrystalline HgI2

    NASA Astrophysics Data System (ADS)

    Zuck, Asaf; Schieber, Michael M.; Khakhan, Oleg; Burshtein, Zeev

    2003-01-01

    Transient charge transport (TCT) measurements were used to evaluate the electrical conduction properties of HgI2 single crystals. Some comparative preliminary results for polycrystalline mercuric iodide (poly-HgI2) thick-film X-ray detectors are also reported. The latter were prepared by physical vapor deposition (PVD). The mobility , trapping time 2, and surface recombination velocity s of electrons or holes were determined by analyses of transient voltages developed across the sample in response to a drift of the corresponding charge carriers created by alpha particle absorption near one of the electrodes. Electron-, and hole mobilities of single crystal HgI2 were n = 80 cm2/Vs and p = 4.8 cm2/Vs, respectively. Trapping times were 2n ? 22 V and 2p ? 8 V, and surface recombination velocities sn ? 1.1 105 cm/s and sp ? 3.6 103 cm/s . Those of the polycrystalline material depend on the deposition technology, and vary between 65 and 88 cm2/Vs for electrons, and between 4.3 and 4.1 cm2/Vs for holes. Bulk trapping-times and surface recombination velocities appear of the same order of magnitude as in the single crystal. An effect of carriers being first generated in near-surface traps and then gradually released is observed for both the single crystal and the polycrystalline material. It is stronger for electrons as compared to holes, and stronger in the polycrystalline material as compared to the single crystal.

  4. Destruction of a single chlorophyll is correlated with the photoinhibition of photosystem II with a transiently inactive donor side.

    PubMed Central

    Bumann, D; Oesterhelt, D

    1995-01-01

    Pigments destroyed during photoinhibition of water-splitting photosystem II core complexes from the green alga Chlamydomonas reinhardtii were studied. Under conditions of a transiently inactivated donor side, illumination leads to an irreversible inhibition of the electron transfer at the donor side that is paralleled by the destruction of chlorophylls a absorbing maximally around 674 and 682 nm. The observed stochiometry of 1 +/- 0.1 destroyed chlorophyll per inhibited photosystem II suggests that chlorophyll destruction could be the primary photodamage causing the inhibition of photosystem II under these conditions. PMID:11607621

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

    NASA Astrophysics Data System (ADS)

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

    2014-09-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2015-01-01

    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.

  7. Numerical and field tests of hydraulic transients at Piva power plant

    NASA Astrophysics Data System (ADS)

    Giljen, Z.

    2014-03-01

    In 2009, a sophisticated field investigation was undertaken and later, in 2011, numerical tests were completed, on all three turbine units at the Piva hydroelectric power plant. These tests were made in order to assist in making decisions about the necessary scope of the reconstruction and modernisation of the Piva hydroelectric power plant, a plant originally constructed in the mid-1970s. More specifically, the investigation included several hydraulic conditions including both the start-up and stopping of each unit, load rejection under governor control from different initial powers, as well as emergency shut-down. Numerical results were obtained using the method of characteristics in a representation that included the full flow system and the characteristics of each associated Francis turbine. The impact of load rejection and emergency shut-down on the penstock pressure and turbine speed changes are reported and numerical and experimental results are compared, showing close agreement.

  8. Variable Depth Bragg Peak Method for Single Event Effects Testing

    NASA Technical Reports Server (NTRS)

    Buchner, S.; Kanyogoro, N.; Foster, C.; O'Neill, P.

    2011-01-01

    Traditionally, accelerator SEE testing is accomplished by removing the tops of packages so that the IC chips are accessible to heavy ions. However, ICs in some advanced packages cannot be de-lidded so a different approach is used that involves grinding and/or chemically etching away part of the package and the chip from the back side. The parts are then tested from the back side with ions having sufficient range to reach the sensitive volume. More recently, the entire silicon substrate in an SOI/SRAM was removed, making it possible to use low-energy ions with shorter ranges. Where removal of part of the package is not possible, facilities at Michigan State, NASA Space Radiation Laboratory, GANIL (France) and GSI (Germany) offer high-energy heavy ions with long ranges so that the ions can reach the devices' sensitive volumes without much change in the LET. Unfortunately, a run will typically involve only one ion species having a single energy and LET due to the long time it takes to tune a new energy. The Variable Depth Bragg Peak (VDBP) method is similar to the above method in that it involves the use of high-energy heavy ions that are able to pass through the packaging material and reach the device, obviating the need to remove the package. However, the method provides a broad range of LETs from a single ion by inserting degraders in the beam that modify the ion energy and, therefore, the LET. The crux of the method involves establishing a fiduciary point for degrader thickness, i.e., where the Bragg peak is located precisely at the sensitive volume in the device, for which the measured SEU cross-section and the ion LET are both also maxima and can be calculated using a Monte-Carlo program, TRIM. Once the fiduciary point has been established, calibrated high density polyethylene (HDPE) degraders are inserted into or removed from the beam to vary the ion LET at the device in a known manner. After each change of degrader thickness, the SEU cross-section is measured and the corresponding LET calculated from the change in degrader thickness. That information is used to generate a plot of cross-section as a function of ion LET. The advantages of this approach are that the part does not have to be de-lidded and a broad range of LETs is available from a single heavy ion without having to go to non-normal angles of incidence to change the "effective" LET. As we will show, it is possible to obtain an entire curve of cross-section versus LET using just two or three ions. Fig. 1 shows curves of cross-section vs LET for a Freescale 4 Mbit SOI/SRAM measured at the 88" Cyclotron at Berkeley and at NSRL. The open symbols are the data obtained from Berkeley for top-side and back-side irradiation. The solid data points are for the data obtained at NSRL using a device for which the package was intact. The data are for Iron and Gold and cover a range of LETs from 4 MeV.cm2/mg to 84 MeV.cm2/mg. The agreement between the data obtained from Berkeley and from NSRL is excellent, demonstrating that the VDBP method is capable of providing accurate values of cross-section versus LET, at least for the 4 Mbit SRAM. Details of the technique will be included in the final presentation.

  9. Phase V of the single-breath washout test

    NASA Technical Reports Server (NTRS)

    Nichol, G. M.; Michels, D. B.; Guy, H. J. B.

    1982-01-01

    A downward-deflecting phase V is often seen following the terminal rise (phase IV) in single-breath washout tests. To investigate the nature of phase V, experiments using simultaneous washouts of N2 and tracer boluses of Ar were performed on eight normal nonsmoking subjects aged 27-41 who exhibited a phase V. Phase V is found to occur in all subjects at expiratory flow rates between 0.1 and 2.0 l/sec shortly after expiration became flow limited. Volumes of both phases IV and V increase with increasing flow rate. The difference between the exhaled volumes at which flow became limited and phase V appeared is shown to be approximately equal to the anatomic dead space. Results support a model of lung emptying in a gravitational field in which flow limitation occurs first in the lower lung regions and then progresses toward the upper regions, causing phase IV. A decrease in the amount of flow from the upper relative to the lower regions after all regions have become flow limited then causes phase V.

  10. 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

    Yamada, Yoji; Sakurada, Kazuhiro; Takeda, Yukiji; Gojo, Satoshi; Umezawa, Akihiro . E-mail: umezawa@1985.jukuin.keio.ac.jp

    2007-02-15

    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.

  11. COBRA-WC: a version of COBRA for single-phase multiassembly thermal hydraulic transient analysis. [LMFBR

    SciTech Connect

    George, T.L.; Basehore, K.L.; Wheeler, C.L.; Prather, W.A.; Masterson, R.E.

    1980-07-01

    The objective of this report is to provide the user of the COBRA-WC (Whole Core) code a basic understanding of the code operation and capabilities. Included in this manual are the equations solved and the assumptions made in their derivations, a general description of the code capabilities, an explanation of the numerical algorithms used to solve the equations, and input instructions for using the code. Also, the auxiliary programs GEOM and SPECSET are described and input instructions for each are given. Input for COBRA-WC sample problems and the corresponding output are given in the appendices. The COBRA-WC code has been developed from the COBRA-IV-I code to analyze liquid Metal Fast Breeder Reactor (LMFBR) assembly transients. It was specifically developed to analyze a core flow coastdown to natural circulation cooling.

  12. Radiation-Induced Transient Effects in Near Infrared Focal Plane Arrays

    NASA Technical Reports Server (NTRS)

    Reed, Robert A.; Pickel, J.; Marshall, P.; Waczynski, A.; McMurray, R.; Gee, G.; Polidan, E.; Johnson, S.; McKeivey, M.; Ennico, K.; Johnson, R.

    2004-01-01

    This viewgraph presentation describes a test simulate the transient effects of cosmic ray impacts on near infrared focal plane arrays. The objectives of the test are to: 1) Characterize proton single events as function of energy and angle of incidence; 2) Measure charge spread (crosstalk) to adjacent pixels; 3) Assess transient recovery time.

  13. 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)

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

    2014-01-01

    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.

  14. Single-stranded DNA as a recombination substrate in plants as assessed by stable and transient recombination assays.

    PubMed Central

    Bilang, R; Peterhans, A; Bogucki, A; Paszkowski, J

    1992-01-01

    Two separate assays, one that requires stable integration of recombination products and one that does not, were employed to elucidate the role of single-stranded DNA in extrachromosomal homologous recombination in Nicotiana tabacum. Both assays revealed that single-stranded DNA in linear and in circular forms was an efficient substrate for recombination, provided that the cotransformed recombination substrates were of complementary sequence, so that direct annealing was possible. Recombination was inefficient when both single-stranded recombination partners contained homologous regions of identical sequence and generation of a double-stranded DNA was required prior to heteroduplex formation. These results indicate that direct annealing of single strands is an important initial step for intermolecular recombination in tobacco cells. Annealed cotransformed single-stranded molecules yielded intermediates that could be further processed by either continuous or discontinuous second-strand synthesis. The type of intermediate had no influence on the recombination efficiency. Double-stranded circles were unable to recombine efficiently either with each other or with single-stranded DNA. Our results suggest that a helicase activity is involved in the initial steps of double-stranded DNA recombination which unwinds duplex molecules at the site of double-strand breaks. Images PMID:1729608

  15. Phase 3 integrated water recovery testing at MSFC: Single loop test results and lessons learned

    NASA Technical Reports Server (NTRS)

    Carter, Donald Layne; Bagdigian, Robert M.

    1993-01-01

    A series of tests has been conducted at the NASA Marshall Space Flight Center (MSFC) to evaluate the performance of the Space Station Freedom (SSF) water recovery system. Potable and urine reclamation processors were integrated with waste water generation equipment and sucessfully operated for a total of 144 days. This testing marked the first occasion in which the waste feed sources for the previous potable and hygiene loops were combined into a single loop and processed to potable water quality. Reclaimed potable water from the combined waste waters routinely met the SSF water quality specifications.In the last stage of testing, data was obtained that indicated that the water processor (WP) presterilizer may not be required to meet the potable water quality specification. The removal of the presterilizer from the Water Processor design would provide a significant power savings, though an increase in the residence time of the catalytic oxidation reactor may be required to meet the potable microbial and total Organic Carbon specifications. This paper summarizes the test objectives, system design, test activities/protocols, significant results/anomalies and major lessons learned.

  16. 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.

  17. A preliminary comparison of the transient effects of single versus multiple q-switched doubled-neodymium laser pulses

    NASA Astrophysics Data System (ADS)

    Previc, Fred H.

    1987-09-01

    A comparison between the effects of single and multiple laser pulse-trains of equivalent energy was performed. Visual evoked potentials (VEPS) recorded bipolarly from the visual cortex of two rhesus monkeys in response to a counterphasing grating were used to assess the magnitude of the visual loss following four types of exposures: single and multiple pulses with total energies equal to 50 and 500 percent of the maximum permissible exposure (MPE) standard for humans. The results showed that the effects of a series of laser flashes presented within 200 ms are similar to those of a single laser flash whose energy is equivalent to the cumulative energy of the multiple-pulse exposure.

  18. Ablation with a single micropatterned KrF laser pulse: quantitative evidence of transient liquid microflow driven by the plume pressure gradient at the surface of polyesters

    NASA Astrophysics Data System (ADS)

    Weisbuch, F.; Tokarev, V. N.; Lazare, S.; Dbarre, D.

    A microscopic flow of a transient liquid film produced by KrF laser ablation is evidenced on targets of PET and PEN. Experiments were done by using single pulses of the excimer laser beam micropatterned with the aid of submicron projection optics and grating masks. The samples of various crystalline states, ablated with a grating-forming beam (period ?=3.7 ?m), were precisely measured by atomic force microscopy, in order to evidence any deviation from the ablation behavior predicted by the current theory (combination of ablation curve and beam profile). This was confirmed by comparing various behaviors dependent on the polymer nature (PC, PET and PEN). PC is a normally ablating polymer in the sense that the ablated profile can be predicted with previous theory neglecting liquid-flow effects. This case is called `dry' ablation and PC is used as a reference material. But, for some particular samples like crystalline PET, it is revealed that during ablation a film of transient liquid, composed of various components, which are discussed, can flow under the transient action of the gradient of the pressure of the ablation plume and resolidify at the border of the spot after the end of the pulse. This mechanism is further supported by a hydrodynamics theoretical model in which a laser-induced viscosity drop and the gradient of the plume pressure play an important role. The volume of displaced liquid increases with fluence (0.5 to 2 J/cm2) and satisfactory quantitative agreement is obtained with the present model. The same experiment done on the same PET polymer but prepared in the amorphous state does not show microflow, and such an amorphous sample behaves like the reference PC (`dry' ablation). The reasons for this surprising result are discussed.

  19. Single- and double-core-hole ion emission spectroscopy of transient neon plasmas produced by ultraintense x-ray laser pulses

    NASA Astrophysics Data System (ADS)

    Gao, Cheng; Zeng, Jiaolong; Yuan, Jianmin

    2016-02-01

    Single-core-hole (SCH) and double-core-hole (DCH) spectroscopy is investigated systematically for neon gas in the interaction with ultraintense x-ray pulses with photon energy from 937 eV to 2000 eV. A time-dependent rate equation, implemented in detailed level accounting approximation, is utilized to study the dynamical evolution of the level population and emission properties of the laser-produced highly transient plasmas. The plasma-density effects on level populations and charge-state distribution are demonstrated with an x-ray photon energy of 2000 eV. It is shown that atomic number density of relevant experiment is about 1 × 1018 cm‑3, which is comparable to a recent experiment. At this density, we systematically investigate the emissivity of the transient neon plasmas. For laser photon energy in the range 937–1360 eV, resonant absorptions (RA) of 1s\\to {np} (n≥slant 2) transitions play important roles in time evolution of the population and DCH emission spectroscopy. The RA effects are illustrated in detail for an x-ray pulse of 944 eV photon energy, which creates the 1s\\to 2p RA from the SCH states (1s2{s}22{p}4, 1s2s2p5, and 1s2p6) of Ne3+. After averaging over the space and time distribution of x-ray pulse, DCH emission spectroscopy is studied at x-ray photon energies of 937, 944, 955, 968, 980, and 990 eV, where there exist 1s\\to 2p resonances from SCH states of Ne2+-Ne7+. The processes with producing DCH states are discussed. For x-ray photon energy larger than 1360 eV, no RA exist and transient plasmas show different features in the DCH spectroscopy.

  20. 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

    Guzman, A.G.; Geddis, A.M.; Henrich, M.J.; Lohrstorfer, C.F.; Neuman, S.P.

    1996-03-01

    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.

  1. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Modification of the single car air brake test... Requirements § 232.307 Modification of the single car air brake test procedures. (a) Request. The AAR or other authorized representative of the railroad industry may seek modification of the single car air brake...

  2. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Modification of the single car air brake test... Requirements 232.307 Modification of the single car air brake test procedures. (a) Request. The AAR or other authorized representative of the railroad industry may seek modification of the single car air brake...

  3. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Modification of the single car air brake test... Requirements 232.307 Modification of the single car air brake test procedures. (a) Request. The AAR or other authorized representative of the railroad industry may seek modification of the single car air brake...

  4. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Modification of the single car air brake test... Requirements § 232.307 Modification of the single car air brake test procedures. (a) Request. The AAR or other authorized representative of the railroad industry may seek modification of the single car air brake...

  5. 49 CFR 232.307 - Modification of the single car air brake test procedures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Modification of the single car air brake test... Requirements § 232.307 Modification of the single car air brake test procedures. (a) Request. The AAR or other authorized representative of the railroad industry may seek modification of the single car air brake...

  6. The mechanism of the transient depression of the erythropoietic rate induced in the rat by a single injection of uranyl nitrate

    SciTech Connect

    Giglio, M.J.; Brandan, N.; Leal, T.L.; Bozzini, C.E.

    1989-06-15

    With the purpose of assessing the effect of uranyl nitrate (UN) on the rate of erythropoiesis, 1 mg/kg of the compound was injected iv to adult female Wistar rats. The dosing vehicle was injected into control animals. A single injection of UN induced a transient depression of the rate of red cell volume /sup 59/Fe uptake, which reached its lowest value (68% depression) by the seventh postinjection day. By 14 days, /sup 59/Fe incorporation had returned to normal. The amount of iron going to erythroid tissue per hour, reticulocyte count, and immunoreactive erythropoietin concentration in both plasma and kidney extracts were also significantly depressed in UN-treated rats in relation to these values in vehicle-injected rats by the seventh postinjection day. Dose-response curves for exogenous erythropoietin (Epo) performed in polycythemic intact and UN-treated rats 7 days after drug injection revealed a significant depression of the response in UN-injected animals. Moreover, bone marrow cells obtained from rats pretreated with UN formed a reduced number of erythroid colonies in vitro in response to Epo. Therefore, possible mechanisms for the observed transient depression in the rate of erythropoiesis associated with acute UN treatment include decreased Epo production and direct or indirect damage of erythroid progenitor cells.

  7. Axial Stretch of Rat Single Ventricular Cardiomyocytes Causes an Acute and Transient Increase in Ca2+ Spark Rate

    PubMed Central

    Iribe, Gentaro; Ward, Christopher W.; Camelliti, Patrizia; Bollensdorff, Christian; Mason, Fleur; Burton, Rebecca A.B.; Garny, Alan; Morphew, Mary K.; Hoenger, Andreas; Lederer, W. Jonathan; Kohl, Peter

    2010-01-01

    We investigate acute effects of axial stretch, applied by carbon fibers (CFs), on diastolic Ca2 spark rate in rat isolated cardiomyocytes. CFs were attached either to both cell ends (to maximize the stretched region), or to the center and one end of the cell (to compare responses in stretched and nonstretched half-cells). Sarcomere length was increased by 8.01 0.94% in the stretched cell fraction, and time series of XY confocal images were recorded to monitor diastolic Ca2 spark frequency and dynamics. Whole-cell stretch causes an acute increase of Ca2 spark rate (to 130.7 6.4%) within 5 seconds, followed by a return to near background levels (to 104.45.1%) within 1 minute of sustained distension. Spark rate increased only in the stretched cell region, without significant differences in spark amplitude, time to peak, and decay time constants of sparks in stretched and nonstretched areas. Block of stretch-activated ion channels (2 gmol/L GsMTx-4), perfusion with Na/Ca2-free solution, and block of nitric oxide synthesis (1 mmol/L L-NAME) all had no effect on the stretch-induced acute increase in Ca2 spark rate. Conversely, interference with cytoskeletal integrity (2 hours of 10 gmol/L colchicine) abolished the response. Subsequent electron microscopic tomography confirmed the close approximation of microtubules with the T-tubularsarcoplasmic reticulum complex (to within 10?8m). In conclusion, axial stretch of rat cardiomyocytes acutely and transiently increases sarcoplasmic reticulum Ca2 spark rate via a mechanism that is independent of sarcolemmal stretch-activated ion channels, nitric oxide synthesis, or availability of extracellular calcium but that requires cytoskeletal integrity. The potential of microtubule-mediated modulation of ryanodine receptor function warrants further investigation. PMID:19197074

  8. Single event effect testing of the Intel 80386 family and the 80486 microprocessor

    SciTech Connect

    Moran, A.; LaBel, K.; Gates, M.; McGraw, R.; Broida, M.; Firer, J.; Sprehn, S.

    1996-06-01

    The authors present single event effect test results for the Intel 80386 microprocessor, the 80387 coprocessor, the 82380 peripheral device, and on the 80486 microprocessor. Both single event upset and latchup conditions were monitored.

  9. Mechanical testing of large thallium doped sodium iodide single crystals

    NASA Technical Reports Server (NTRS)

    Lee, H. M.

    1985-01-01

    The findings of mechanical tests performed on five thallium-doped sodium iodide NaI(Tl) crystals are presented. These crystals are all in the shape of circular flat plates, 20.0 in. in diameter an d0.5 in. thick. The test setup, testing procedure, and the test data are presented. Large crystals exhibit a high degree of material plasticity, as well as a much higher strength than previously anticipated, on the order of 500 psi. Also revealed from the testing is the fact that crystal with a large number of grain boundaries developed less plasticity, and therefore less permanent deformation, than those with fewer grain boundaries.

  10. Single-molecule spectroscopy and femtosecond transient absorption studies on the excitation energy transfer process in ApcE(1-240) dimers.

    PubMed

    Long, Saran; Zhou, Meng; Tang, Kun; Zeng, Xiao-Li; Niu, Yingli; Guo, Qianjin; Zhao, Kai-Hong; Xia, Andong

    2015-05-28

    ApcE(1-240) dimers with one intrinsic phycocyanobilin (PCB) chromophore in each monomer that is truncated from the core-membrane linker (ApcE) of phycobilisomes (PBS) in Nostoc sp. PCC 7120 show a sharp and significantly red-shifted absorption. Two explanations either conformation-dependent Frster resonance energy transfer (FRET) or the strong exciton coupling limit have been proposed for red-shifted absorption. This is a classic example of the special pair in the photosynthetic light harvesting proteins, but the mechanism of this interaction is still a matter of intense debate. We report the studies using single-molecule and transient absorption spectra on the interaction in the special pair of ApcE dimers. Our results demonstrate the presence of conformation-dependent FRET between the two PCB chromophores in ApcE dimers. The broad distributions of fluorescence intensities, lifetimes and polarization difference from single-molecule measurements reveal the heterogeneity of local protein-pigment environments in ApcE dimers, where the same molecular structures but different protein environments are the main reason for the two PCB chromophores with different spectral properties. The excitation energy transfer rate between the donor and the acceptor about (110 ps)(-1) is determined from transient absorption measurements. The red-shifted absorption in ApcE dimers could result from more extending conformation, which shows another type of absorption redshift that does not depend on strong exciton coupling. The results here stress the importance of conformation-controlled spectral properties of the chemically identical chromophores, which could be a general feature to control energy/electron transfer, widely existing in the light harvesting complexes. PMID:25925197

  11. Test report for single event effects of the 80386DX microprocessor

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

    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.

  12. Transient Behaviour of Batch Arrival Queue with N-Policy and Single Vacation (Mx/G/1/N-POLICY)

    NASA Astrophysics Data System (ADS)

    Solanki, Anjana

    2009-07-01

    In this paper Mx/G/1 queuing system with N-policy and single vacation is considered. As soon as the system becomes empty, the server leaves the system for a vacation of random length V. When he returns from the vacation, if the system size is greater then or equal to predetermined value N (threshold), he begins to serve the customers. If not, the server waits in the system until the system size reaches or exceeds N. Here the time dependent system size distribution is obtained.

  13. Thermal modeling of the NASA-Ames Research Center Cryogenic Optical Test Facility and a single-arch, fused-natural-quartz mirror

    NASA Technical Reports Server (NTRS)

    Ng, Y. S.; Augason, Gordon C.; Young, Jeffrey A.; Howard, Steven D.; Melugin, Ramsey K.

    1990-01-01

    A thermal model of the dewar and optical system of the Cryogenic Optical Test Facility at NASA-Ames Research Center was developed using the computer codes SINDA and MONTE CARLO. The model was based on the geometry, boundary conditions, and physical properties of the test facility and was developed to investigate heat transfer mechanisms and temperatures in the facility and in test mirrors during cryogenic optical tests. A single-arch, fused-natural-quartz mirror was the first mirror whose thermal loads and temperature distributions were modeled. From the temperature distribution, the thermal gradients in the mirror were obtained. The model predicted that a small gradient should exist for the single arch mirror. This was later verified by the measurement of mirror temperatures. The temperatures, predicted by the model at various locations within the dewar, were in relatively good agreement with the measured temperatures. The model is applicable to both steady-state and transient cooldown operations.

  14. Single photons in an imperfect array of beam-splitters: interplay between percolation, backscattering and transient localization

    NASA Astrophysics Data System (ADS)

    Chandrashekar, C. M.; Melville, S.; Busch, Th

    2014-04-01

    Photons in optical networks can be used in multi-path interferometry and various quantum information processing and communication protocols. Large networks, however, are often not free from defects, which can appear randomly between the lattice sites and are caused either by production faults or deliberate introduction. In this work we present numerical simulations of the behaviour of a single photon injected into a regular lattice of beam-splitting components in the presence of defects that cause perfect backward reflections. We find that the photon dynamics is quickly dominated by the backscattering processes, and a small fraction of reflectors in the paths of the beam-splitting array strongly affects the percolation probability of the photon. We carefully examine such systems and show an interesting interplay between the probabilities of percolation, backscattering and temporary localization. We also discuss the sensitivity of these probabilities to lattice size, timescale, injection point, fraction of reflectors and boundary conditions.

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

    NASA Technical Reports Server (NTRS)

    1977-01-01

    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.

  16. Neutronics, steady-state, and transient analyses for the Poland MARIA reactor for irradiation testing of LEU lead test fuel assemblies from CERCA : ANL independent verification results.

    SciTech Connect

    Garner, P. L.; Hanan, N. A.

    2011-06-07

    The MARIA reactor at the Institute of Atomic Energy (IAE) in Swierk (30 km SE of Warsaw) in the Republic of Poland is considering conversion from high-enriched uranium (HEU) to low-enriched uranium (LEU) fuel assemblies (FA). The FA design in MARIA is rather unique; a suitable LEU FA has never been designed or tested. IAE has contracted with CERCA (the fuel supply portion of AREVA in France) to supply 2 lead test assemblies (LTA). The LTAs will be irradiated in MARIA to burnup level of at least 40% for both LTAs and to 60% for one LTA. IAE may decide to purchase additional LEU FAs for a full core conversion after the test irradiation. The Reactor Safety Committee within IAE and the National Atomic Energy Agency in Poland (PAA) must approve the LTA irradiation process. The approval will be based, in part, on IAE submitting revisions to portions of the Safety Analysis Report (SAR) which are affected by the insertion of the LTAs. (A similar process will be required for the full core conversion to LEU fuel.) The analysis required was established during working meetings between Argonne National Laboratory (ANL) and IAE staff during August 2006, subsequent email correspondence, and subsequent staff visits. The analysis needs to consider the current high-enriched uranium (HEU) core and 4 core configurations containing 1 and 2 LEU LTAs in various core positions. Calculations have been performed at ANL in support of the LTA irradiation. These calculations are summarized in this report and include criticality, burn-up, neutronics parameters, steady-state thermal hydraulics, and postulated transients. These calculations have been performed at the request of the IAE staff, who are performing similar calculations to be used in their SAR amendment submittal to the PAA. The ANL analysis has been performed independently from that being performed by IAE and should only be used as one step in the verification process.

  17. ORNL rod-bundle heat-transfer test data. Volume 3. Thermal-hydraulic test facility experimental data report for test 3. 06. 6B - transient film boiling in upflow. [PWR

    SciTech Connect

    Mullins, C.B.; Felde, D.K.; Sutton, A.G.; Gould, S.S.; Morris, D.G.; Robinson, J.J.

    1982-05-01

    Reduced instrument responses are presented for Thermal-Hyraulic Test Facility (THTF) Test 3.06.6B. This test was conducted by members of the Oak Ridge National Laboratory Pressurized-Water-Reactor (PWR) Blowdown Heat Transfer (BDHT) Separate-Effects Program on August 29, 1980. The objective of the program was to investigate heat transfer phenomena believed to occur in PWR's during accidents, including small and large break loss-of-coolant accidents. Test 3.06.6B was conducted to obtain transient film boiling data in rod bundle geometry under reactor accident-type conditions. The primary purpose of this report is to make the reduced instrument responses for THTF Test 3.06.6B available. Included in the report are uncertainties in the instrument responses, calculated mass flows, and calculated rod powers.

  18. Maternal single injection of N-methyl-N-nitrosourea to cause microcephaly in offspring induces transient aberration of hippocampal neurogenesis in mice.

    PubMed

    Takimoto, Norifumi; Wang, Liyun; Itahashi, Megu; Ogawa, Takashi; Segawa, Risa; Hara, Shintaro; Murakami, Tomoaki; Suzuki, Kazuhiko; Shibutani, Makoto

    2014-04-01

    N-Methyl-N-nitrosourea (MNU) is an alkylating agent having antiproliferative cytotoxity targeting the neural stem/progenitor cells to cause microcephaly by maternal exposure. This study investigated the effect of transient exposure to MNU on the process of hippocampal neurogenesis in later life using mice. Pregnant mice received a single injection of MNU at 0, 5 and 10 mg/kg body weight, intraperitoneally on gestational day 14, and their offspring were examined on postnatal day (PND) 21 and PND 77. On PND 21, offspring displayed microcephaly and hippocampal formation hypoplasia at 10 mg/kg, decrease of doublecortin (Dcx)(+) cells in the dentate subgranular zone from 5mg/kg, and decrease of TUNEL(+) apoptotic cells and increase of transcript expression of anti-apoptotic Bcl-2 at 10 mg/kg in the dentate gyrus. In the dentate hilus, numbers of reelin(+) or parvalbumin (Pvalb)(+) interneurons or neuron-specific nuclear protein(+) neurons increased at 10 mg/kg. Microcephaly and hippocampal formation hypoplasia continued through PND 77 at 10 mg/kg. Thus, apart from the massive cell killing at the migratory stream causing microcephaly, MNU may decrease Dcx(+) cells reflecting disruption of the differentiation process of late-stage neuronal progenitors and immature granule cells through defective molecular functions by gene mutations. Increase of reelin(+) and Pvalb(+) cells may reflect the disruption of neurogenesis and following neuronal migration. All of the granule cell lineage and interneuron changes disappeared at the adult stage on PND 77 suggesting that MNU mainly targets transient populations of highly proliferative progenitor cells but hardly affects their stem cells having self-renewal ability. PMID:24463056

  19. Predictions of Transient Flame Lift-Off Length With Comparison to Single-Cylinder Optical Engine Experiments

    DOE PAGESBeta

    Senecal, P. K.; Pomraning, E.; Anders, J. W.; Weber, M. R.; Gehrke, C. R.; Polonowski, C. J.; Mueller, C. J.

    2014-05-28

    A state-of-the-art, grid-convergent simulation methodology was applied to three-dimensional calculations of a single-cylinder optical engine. A mesh resolution study on a sector-based version of the engine geometry further verified the RANS-based cell size recommendations previously presented by Senecal et al. (“Grid Convergent Spray Models for Internal Combustion Engine CFD Simulations,” ASME Paper No. ICEF2012-92043). Convergence of cylinder pressure, flame lift-off length, and emissions was achieved for an adaptive mesh refinement cell size of 0.35 mm. Furthermore, full geometry simulations, using mesh settings derived from the grid convergence study, resulted in excellent agreement with measurements of cylinder pressure, heat release rate,more » and NOx emissions. On the other hand, the full geometry simulations indicated that the flame lift-off length is not converged at 0.35 mm for jets not aligned with the computational mesh. Further simulations suggested that the flame lift-off lengths for both the nonaligned and aligned jets appear to be converged at 0.175 mm. With this increased mesh resolution, both the trends and magnitudes in flame lift-off length were well predicted with the current simulation methodology. Good agreement between the overall predicted flame behavior and the available chemiluminescence measurements was also achieved. Our present study indicates that cell size requirements for accurate prediction of full geometry flame lift-off lengths may be stricter than those for global combustion behavior. This may be important when accurate soot predictions are required.« less

  20. Predictions of Transient Flame Lift-Off Length With Comparison to Single-Cylinder Optical Engine Experiments

    SciTech Connect

    Senecal, P. K.; Pomraning, E.; Anders, J. W.; Weber, M. R.; Gehrke, C. R.; Polonowski, C. J.; Mueller, C. J.

    2014-05-28

    A state-of-the-art, grid-convergent simulation methodology was applied to three-dimensional calculations of a single-cylinder optical engine. A mesh resolution study on a sector-based version of the engine geometry further verified the RANS-based cell size recommendations previously presented by Senecal et al. (“Grid Convergent Spray Models for Internal Combustion Engine CFD Simulations,” ASME Paper No. ICEF2012-92043). Convergence of cylinder pressure, flame lift-off length, and emissions was achieved for an adaptive mesh refinement cell size of 0.35 mm. Furthermore, full geometry simulations, using mesh settings derived from the grid convergence study, resulted in excellent agreement with measurements of cylinder pressure, heat release rate, and NOx emissions. On the other hand, the full geometry simulations indicated that the flame lift-off length is not converged at 0.35 mm for jets not aligned with the computational mesh. Further simulations suggested that the flame lift-off lengths for both the nonaligned and aligned jets appear to be converged at 0.175 mm. With this increased mesh resolution, both the trends and magnitudes in flame lift-off length were well predicted with the current simulation methodology. Good agreement between the overall predicted flame behavior and the available chemiluminescence measurements was also achieved. Our present study indicates that cell size requirements for accurate prediction of full geometry flame lift-off lengths may be stricter than those for global combustion behavior. This may be important when accurate soot predictions are required.

  1. 49 CFR 238.311 - Single car test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... FRA pursuant to § 238.21. The incorporation by reference of this APTA standard was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain a... be performed in accordance with either APTA Standard SS-M-005-98, “Code of Tests for Passenger...

  2. Groin Exploration for the Nonpalpable Testes: A Single Center Experience

    PubMed Central

    Sowande, Oludayo A; Talabi, Ademola O; Etonyeaku, Amarachukwu C; Adejuyigbe, Olusanya

    2015-01-01

    Background: Management of non-palpable testes in Nigeria can be difficult due to late presentation and poor resources. Surgical exploration is often required for diagnosis and treatment. Aim: This study reviews the management outcome of clinically non-palpable testeis in a tertiary center in Nigeria. Materials and Methods: Ten years retrospective review of all clinically non-palpable testes in children aged 215years managed at the Obafemi Awolowo University Teaching Hospitals Complex Ile-Ife Nigeria. Results: Thirty two children with 44 testicular units were managed. The right side was involved in 12 (37.5%); left in 8 (25.0%) and bilateral in 12 (37.5%) patients. Pre-operative ultrasound was done in 12 patients with localization in just 4 patients (33.3% success rate). At groin exploration, 34 (77.32%) testicular units were located in the inguinal canal. Eight patients with 10 The remaining 10 (22.7%) testicular units required additional mini-laparotomy for which six (13.6%) and 4 (9.1%) testicular units respectively were either in the retroperitoneum or not found. Of the testes in the groin, twenty two (64.7%) testicular units were normal while 12 (35.3%) were atrophic. Four of the retroperitoneal testes were normal while 2 were atrophic. Eight (22.5%) testicular units among the inguinal group had multi-staged orchidopexy; while 2 each of the retroperitoneal group had orchidectomy, one stage orchidopexy, two staged Fowler Stephens (F-S) procedure or lost to follow up after first stage of F-S procedure. Mean follow up period was 2 months. 2 testicular units each had retracted or vanished respectively during follow up. Conclusion: Groin exploration still offers a viable approach Surgical exploration is still useful in to the management of non-palpable testes in low resource environment despite the lack of laparoscopy. PMID:25838769

  3. Dynamic tensile test of single PET textile cables

    NASA Astrophysics Data System (ADS)

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

    2012-08-01

    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).

  4. 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

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

    1992-09-01

    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.

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

    SciTech Connect

    Duncan, J.B.

    1997-01-07

    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.

  6. Parametric Testing of Chevrons on Single Flow Hot Jets

    NASA Technical Reports Server (NTRS)

    Bridges, James; Brown, Clifford A.

    2004-01-01

    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.

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

    SciTech Connect

    Ackermann, M.R.; Browning, J.S. ); Hughlock, B.W. ); Lum, G.K. ); Tsacoyeanes, W.C. Lab., Inc., Cambridge, MA ); Weeks, M.D. )

    1990-09-01

    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.

  8. Initial Neutronics Analyses for HEU to LEU Fuel Conversion of the Transient Reactor Test Facility (TREAT) at the Idaho National Laboratory

    SciTech Connect

    Kontogeorgakos, D.; Derstine, K.; Wright, A.; Bauer, T.; Stevens, J.

    2013-06-01

    The purpose of the TREAT reactor is to generate large transient neutron pulses in test samples without over-heating the core to simulate fuel assembly accident conditions. The power transients in the present HEU core are inherently self-limiting such that the core prevents itself from overheating even in the event of a reactivity insertion accident. The objective of this study was to support the assessment of the feasibility of the TREAT core conversion based on the present reactor performance metrics and the technical specifications of the HEU core. The LEU fuel assembly studied had the same overall design, materials (UO2 particles finely dispersed in graphite) and impurities content as the HEU fuel assembly. The Monte Carlo NParticle code (MCNP) and the point kinetics code TREKIN were used in the analyses.

  9. Psychometric Characteristics of Single-Word Tests of Children's Speech Sound Production

    ERIC Educational Resources Information Center

    Flipsen, Peter, Jr.; Ogiela, Diane A.

    2015-01-01

    Purpose: Our understanding of test construction has improved since the now-classic review by McCauley and Swisher (1984) . The current review article examines the psychometric characteristics of current single-word tests of speech sound production in an attempt to determine whether our tests have improved since then. It also provides a resource

  10. Psychometric Characteristics of Single-Word Tests of Children's Speech Sound Production

    ERIC Educational Resources Information Center

    Flipsen, Peter, Jr.; Ogiela, Diane A.

    2015-01-01

    Purpose: Our understanding of test construction has improved since the now-classic review by McCauley and Swisher (1984) . The current review article examines the psychometric characteristics of current single-word tests of speech sound production in an attempt to determine whether our tests have improved since then. It also provides a resource…

  11. Transient performance

    NASA Astrophysics Data System (ADS)

    Curnock, Barry

    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.

  12. Compendium of Recent Test Results of Single Event Effects Conducted by the Jet Propulsion Laboratory

    NASA Technical Reports Server (NTRS)

    Allen, Gregory R.; Guertin, Steven M.; Scheick, Leif Z.; Irom, Farokh; Zajac, Stephanie

    2012-01-01

    This paper reports heavy ion, proton, and laser induced single event effects results for a variety of microelectronic devices targeted for possible use in NASA spacecrafts. The compendium covers devices tested within the years of 2010 through 2012.

  13. 78 FR 44189 - Petition for Modification of Single Car Air Brake Test Procedures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-23

    ..., 2000 (65 FR 19477). Robert C. Lauby, Deputy Associate Administrator for Regulatory and Legislative... Federal Railroad Administration Petition for Modification of Single Car Air Brake Test Procedures In... the Federal Railroad Administration (FRA) per 49 CFR 232.307 to modify the single car air brake...

  14. Single Mothers and Psychological Well-Being: A Test of the Stress and Vulnerability Hypotheses.

    ERIC Educational Resources Information Center

    McLanahan, Sara S.

    Recent studies indicate that single mothers experience unusually high levels of psychological distress. The purpose of this paper is to compare rival explanations for these high levels. Four hypotheses are tested: (1) the psychological well-being of single mothers, relative to married parents, declines over time; (2) changes in psychological…

  15. 76 FR 34801 - Petition for Modification of Single Car Air Brake Test Procedures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-14

    ... Federal Railroad Administration Petition for Modification of Single Car Air Brake Test Procedures In... (PATH) has requested the Federal Railroad Administration (FRA) grant a modification of the single car... FRA-2010-0174. PATH operates a fleet of 25 flat cars in consist with revenue cars utilized...

  16. Single Mothers and Psychological Well-Being: A Test of the Stress and Vulnerability Hypotheses.

    ERIC Educational Resources Information Center

    McLanahan, Sara S.

    Recent studies indicate that single mothers experience unusually high levels of psychological distress. The purpose of this paper is to compare rival explanations for these high levels. Four hypotheses are tested: (1) the psychological well-being of single mothers, relative to married parents, declines over time; (2) changes in psychological

  17. Myelin Water Fraction Is Transiently Reduced after a Single Mild Traumatic Brain Injury – A Prospective Cohort Study in Collegiate Hockey Players

    PubMed Central

    Vavasour, Irene; Shahinfard, Elham; Kolind, Shannon; van Donkelaar, Paul; Taunton, Jack; Li, David; Rauscher, Alexander

    2016-01-01

    Impact-related mild traumatic brain injuries (mTBI) are a major public health concern, and remain as one of the most poorly understood injuries in the field of neuroscience. Currently, the diagnosis and management of such injuries are based largely on patient-reported symptoms. An improved understanding of the underlying pathophysiology of mTBI is urgently needed in order to develop better diagnostic and management protocols. Specifically, dynamic post-injury changes to the myelin sheath in the human brain have not been examined, despite ‘compromised white matter integrity’ often being described as a consequence of mTBI. In this preliminary cohort study, myelin water imaging was used to prospectively evaluate changes in myelin water fraction, derived from the T2 decay signal, in two varsity hockey teams (45 players) over one season of athletic competition. 11 players sustained a concussion during competition, and were scanned at 72 hours, 2 weeks, and 2 months post-injury. Results demonstrated a reduction in myelin water fraction at 2 weeks post-injury in several brain areas relative to preseason scans, including the splenium of the corpus callosum, right posterior thalamic radiation, left superior corona radiata, left superior longitudinal fasciculus, and left posterior limb of the internal capsule. Myelin water fraction recovered to pre-season values by 2 months post-injury. These results may indicate transient myelin disruption following a single mTBI, with subsequent remyelination of affected neurons. Myelin disruption was not apparent in the athletes who did not experience a concussion, despite exposure to repetitive subconcussive trauma over a season of collegiate hockey. These findings may help to explain many of the metabolic and neurological deficits observed clinically following mTBI. PMID:26913900

  18. Myelin Water Fraction Is Transiently Reduced after a Single Mild Traumatic Brain Injury - A Prospective Cohort Study in Collegiate Hockey Players.

    PubMed

    Wright, Alexander D; Jarrett, Michael; Vavasour, Irene; Shahinfard, Elham; Kolind, Shannon; van Donkelaar, Paul; Taunton, Jack; Li, David; Rauscher, Alexander

    2016-01-01

    Impact-related mild traumatic brain injuries (mTBI) are a major public health concern, and remain as one of the most poorly understood injuries in the field of neuroscience. Currently, the diagnosis and management of such injuries are based largely on patient-reported symptoms. An improved understanding of the underlying pathophysiology of mTBI is urgently needed in order to develop better diagnostic and management protocols. Specifically, dynamic post-injury changes to the myelin sheath in the human brain have not been examined, despite 'compromised white matter integrity' often being described as a consequence of mTBI. In this preliminary cohort study, myelin water imaging was used to prospectively evaluate changes in myelin water fraction, derived from the T2 decay signal, in two varsity hockey teams (45 players) over one season of athletic competition. 11 players sustained a concussion during competition, and were scanned at 72 hours, 2 weeks, and 2 months post-injury. Results demonstrated a reduction in myelin water fraction at 2 weeks post-injury in several brain areas relative to preseason scans, including the splenium of the corpus callosum, right posterior thalamic radiation, left superior corona radiata, left superior longitudinal fasciculus, and left posterior limb of the internal capsule. Myelin water fraction recovered to pre-season values by 2 months post-injury. These results may indicate transient myelin disruption following a single mTBI, with subsequent remyelination of affected neurons. Myelin disruption was not apparent in the athletes who did not experience a concussion, despite exposure to repetitive subconcussive trauma over a season of collegiate hockey. These findings may help to explain many of the metabolic and neurological deficits observed clinically following mTBI. PMID:26913900

  19. Switching transients in a superconducting coil

    SciTech Connect

    Owen, E.W.; Shimer, D.W.

    1983-11-18

    A study is made 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 performance tests on the MFTF Yin-yang coils. It is found that the breaker opening time is the critical factor in determining the size and shape of the transient. Instantaneous opening of the breaker causes a lightly damped transient with large amplitude voltages to ground. Increasing the opening time causes the transient to become a monopulse of decreasing amplitude. The voltages at the external terminals are determined by the parameters of the external circuit. For fast opening times the frequency depends on the dump resistor inductance, the circuit capacitance, and the amplitude on the coil current. For slower openings the dump resistor inductance and the current determine the amplitude of the voltage to ground at the terminals. Voltages to ground are less in the interior of the coil, where transients related to the parameters of the coil itself are observed.

  20. DESIGN AND PERFORMANCE OF SINGLE-WELL TRACER TESTS AT THE MOBILE SITE

    EPA Science Inventory

    Tracer tests are the most reliable field methods for obtaining information describing advection and dispersion in aquifers. The paper describes the design and performance of single-well tracer tests utilizing multilevel observation wells at a field site near Mobile, Alabama. In a...

  1. 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...

  2. 10 CFR 26.165 - Testing split specimens and retesting single specimens.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Testing split specimens and retesting single specimens. 26.165 Section 26.165 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Laboratories Certified by the Department of Health and Human Services 26.165 Testing split specimens and...

  3. Role of optometry school in single day large scale school vision testing

    PubMed Central

    Anuradha, N; Ramani, Krishnakumar

    2015-01-01

    Background: School vision testing aims at identification and management of refractive errors. Large-scale school vision testing using conventional methods is time-consuming and demands a lot of chair time from the eye care professionals. A new strategy involving a school of optometry in single day large scale school vision testing is discussed. Aim: The aim was to describe a new approach of performing vision testing of school children on a large scale in a single day. Materials and Methods: A single day vision testing strategy was implemented wherein 123 members (20 teams comprising optometry students and headed by optometrists) conducted vision testing for children in 51 schools. School vision testing included basic vision screening, refraction, frame measurements, frame choice and referrals for other ocular problems. Results: A total of 12448 children were screened, among whom 420 (3.37%) were identified to have refractive errors. 28 (1.26%) children belonged to the primary, 163 to middle (9.80%), 129 (4.67%) to secondary and 100 (1.73%) to the higher secondary levels of education respectively. 265 (2.12%) children were referred for further evaluation. Conclusion: Single day large scale school vision testing can be adopted by schools of optometry to reach a higher number of children within a short span. PMID:25709271

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

    NASA Technical Reports Server (NTRS)

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

    2000-01-01

    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.

  5. A comparison of single-cycle versus multi-cycle proof testing strategies

    NASA Technical Reports Server (NTRS)

    Hudak, Stephen J., Jr.; Russell, Dale A.

    1988-01-01

    Proof testing was a useful supplement to conventional nondestructive evaluation (NDE) of space shuttle main engine (SSME) components. Since many of these components involve thin sections and high toughness materials, such as Inconel 718, conventional single-cycle proof test logic is not applicable due to the propensity for stable crack growth during the proof tests. Experience with five-cycle proof testing of SSME components is summarized and a framework is outlined for understanding multi-cycle proof testing using the fracture mechanics concept of a resistance curve. Extreme value statistics are also used to propose an empirical approach to compare the advantages and disadvantages of single- versus multi-cycle proof testing. The importance of the initial flaw size distribution and specimen thickness in such a comparison is also discussed.

  6. Incorporating Single-Locus Tests into Haplotype Cladistic Analysis in Case-Control Studies

    PubMed Central

    Liu, Jianfeng; Papasian, Chris; Deng, Hong-Wen

    2007-01-01

    In case-control studies, genetic associations for complex diseases may be probed either with single-locus tests or with haplotype-based tests. Although there are different views on the relative merits and preferences of the two test strategies, haplotype-based analyses are generally believed to be more powerful to detect genes with modest effects. However, a main drawback of haplotype-based association tests is the large number of distinct haplotypes, which increases the degrees of freedom for corresponding test statistics and thus reduces the statistical power. To decrease the degrees of freedom and enhance the efficiency and power of haplotype analysis, we propose an improved haplotype clustering method that is based on the haplotype cladistic analysis developed by Durrant et al. In our method, we attempt to combine the strengths of single-locus analysis and haplotype-based analysis into one single test framework. Novel in our method is that we develop a more informative haplotype similarity measurement by using p-values obtained from single-locus association tests to construct a measure of weight, which to some extent incorporates the information of disease outcomes. The weights are then used in computation of similarity measures to construct distance metrics between haplotype pairs in haplotype cladistic analysis. To assess our proposed new method, we performed simulation analyses to compare the relative performances of (1) conventional haplotype-based analysis using original haplotype, (2) single-locus allele-based analysis, (3) original haplotype cladistic analysis (CLADHC) by Durrant et al., and (4) our weighted haplotype cladistic analysis method, under different scenarios. Our weighted cladistic analysis method shows an increased statistical power and robustness, compared with the methods of haplotype cladistic analysis, single-locus test, and the traditional haplotype-based analyses. The real data analyses also show that our proposed method has practical significance in the human genetics field. PMID:17381242

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

    SciTech Connect

    Crotts, Arlin P. S.; Hummels, Cameron

    2009-12-20

    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.

  8. RECENT ADVANCES IN HIGH TEMPERATURE ELECTROLYSIS AT IDAHO NATIONAL LABORATORY: SINGLE CELL TESTS

    SciTech Connect

    X. Zhang; J. E. O'Brien; R. C. O'Brien

    2012-07-01

    An experimental investigation on the performance and durability of single solid oxide electrolysis cells (SOECs) is under way at the Idaho National Laboratory. In order to understand and mitigate the degradation issues in high temperature electrolysis, single SOECs with different configurations from several manufacturers have been evaluated for initial performance and long-term durability. A new test apparatus has been developed for single cell and small stack tests from different vendors. Single cells from Ceramatec Inc. show improved durability compared to our previous stack tests. Single cells from Materials and Systems Research Inc. (MSRI) demonstrate low degradation both in fuel cell and electrolysis modes. Single cells from Saint Gobain Advanced Materials (St. Gobain) show stable performance in fuel cell mode, but rapid degradation in the electrolysis mode. Electrolyte-electrode delamination is found to have significant impact on degradation in some cases. Enhanced bonding between electrolyte and electrode and modification of the microstructure help to mitigate degradation. Polarization scans and AC impedance measurements are performed during the tests to characterize the cell performance and degradation.

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

    NASA Technical Reports Server (NTRS)

    Sorge, Richard N.

    2013-01-01

    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.

  10. Advanced sluicing system test report for single shell tank waste retrieval integrated testing

    SciTech Connect

    Berglin, E.J.

    1997-05-29

    This document describes the testing performed by ARD Environmental, Inc., and Los Alamos Technical Associates of the LATA/ARD Advanced Sluicing System, in support of ACTR Phase 1 activities. Testing was to measure the impact force and pressures of sluicing streams at three different distances, as measured by the Government supplied load cell. Simulated sluicing of large simulated salt cake and hard pan waste coupons was also performed. Due to operational difficulties experienced with the Government supplied load cell, no meaningful results with respect to sluice stream impact pressure distribution or stream coherence were obtained. Sluice testing using 3000 psi salt cake simulants measured waste retrieval rates of approximately 12 Ml/day (17.6 ft{sup 3}/hr). Rates as high as 314 m{sup 3}/day (463 ft{sup 3}/hr) were measured against the lower strength salt cake simulants.

  11. Single event upset susceptibility testing of the Xilinx Virtex II FPGA

    NASA Technical Reports Server (NTRS)

    Yui, C.; Swift, G.; Carmichael, C.

    2002-01-01

    Heavy ion testing of the Xilinx Virtex IZ was conducted on the configuration, block RAM and user flip flop cells to determine their single event upset susceptibility using LETs of 1.2 to 60 MeVcm^2/mg. A software program specifically designed to count errors in the FPGA is used to reveal L1/e values and single-event-functional interrupt failures.

  12. Comparative performance of four single extreme outlier discordancy tests from Monte Carlo simulations.

    PubMed

    Verma, Surendra P; Díaz-González, Lorena; Rosales-Rivera, Mauricio; Quiroz-Ruiz, Alfredo

    2014-01-01

    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 δ from ±0.1 up to ±20 for modeling the slippage of central tendency or ε from ±1.1 up to ±200 for slippage of dispersion, as well as no contamination (δ = 0 and ε = ±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

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

    PubMed Central

    Díaz-González, Lorena; Quiroz-Ruiz, Alfredo

    2014-01-01

    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 δ from ±0.1 up to ±20 for modeling the slippage of central tendency or ε from ±1.1 up to ±200 for slippage of dispersion, as well as no contamination (δ = 0 and ε = ±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

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

    USGS Publications Warehouse

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

    1997-01-01

    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.

  15. Crash tests of three identical low-wing single-engine airplane

    NASA Technical Reports Server (NTRS)

    Castle, C. B.; Alfaro-Bou, E.

    1983-01-01

    Three identical four place, low wing single engine airplane specimens with nominal masses of 1043 kg were crash tested under controlled free flight conditions. The tests were conducted at the same nominal velocity of 25 m/sec along the flight path. Two airplanes were crashed on a concrete surface (at 10 and 30 deg pitch angles), and one was crashed on soil (at a -30 deg pitch angle). The three tests revealed that the specimen in the -30 deg test on soil sustained massive structural damage in the engine compartment and fire wall. Also, the highest longitudinal cabin floor accelerations occurred in this test. Severe damage, but of lesser magnitude, occurred in the -30 deg test on concrete. The highest normal cabin floor accelerations occurred in this test. The least structural damage and lowest accelerations occurred in the 10 deg test on concrete.

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

    SciTech Connect

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

    1992-09-01

    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.

  17. Testing Landscape Theory for Biomolecular Processes with Single Molecule Fluorescence Spectroscopy

    NASA Astrophysics Data System (ADS)

    Truex, Katherine; Chung, Hoi Sung; Louis, John M.; Eaton, William A.

    2015-07-01

    Although Kramers' theory for diffusive barrier crossing on a 1D free energy profile plays a central role in landscape theory for complex biomolecular processes, it has not yet been rigorously tested by experiment. Here we test this 1D diffusion scenario with single molecule fluorescence measurements of DNA hairpin folding. We find an upper bound of 2.5 ? s for the average transition path time, consistent with the predictions by theory with parameters determined from optical tweezer measurements.

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

    SciTech Connect

    Johansson, K.; Dyreklev, P.; Granbom, B.; Calvet, C.; Fourtine, S.; Feuillatre, O.

    1998-06-01

    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.

  19. Critical predicted no effect concentrations (PNECs) should not be based on a single toxicity test.

    PubMed

    Chapman, Peter M; Elphick, James R

    2015-05-01

    Predicted no-effect concentrations (PNECs), which represent the concentration of a substance below which an unacceptable effect most likely will not occur, are widely used for risk assessment and in environmental policy and regulation. They are typically based on single-species laboratory toxicity tests; often, a single test result for the most sensitive endpoints drives the derivation of a PNEC. In the present study, the authors provide a case study emphasizing the importance of determining the reliability of those most sensitive endpoints. Five 21-d Daphnia magna toxicity tests conducted using the same procedures by 2 laboratories gave 20% inhibitory concentration responses to a specific ionic composition of total dissolved solids that varied from 684?mg/L to more than 1510?mg/L. The concentration-response curve was shallow; thus, these differences could have been attributable to chance alone. The authors strongly recommend that the most sensitive endpoints that determine PNECs not be based on a single toxicity test result but rather on the geometric mean of at least 3 test results to adequately assess and bound test variability, especially when the concentration-response curve is shallow. PMID:25615521

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

    NASA Astrophysics Data System (ADS)

    Roach, Andrew Michael

    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.

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

    NASA Technical Reports Server (NTRS)

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

    1973-01-01

    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.

  2. The effectiveness of combined gripping method in tensile testing of UHMWPE single yarn

    NASA Astrophysics Data System (ADS)

    Wang, H. X.; Hazell, P. J.; Shankar, K.; Morozov, E. V.; Escobedo, J. P.

    2015-07-01

    This paper presents the experimental study on the effectiveness of combined gripping method employed in the tensile testing of UHMWPE (Dyneema® SK75) single yarn. Seven different solutions including epoxy, acrylic, and ethyl cyanoacrylate adhesives were tested under quasi-static loadings in order to determine the most effective adhesive for bonding UHMWPE single yarn to aluminium sheets. The ethyl cyanoacrylate adhesive combined with polyolefin surface primer was found to be the best choice which could prevent yarn slippage and ensure the failure of yarn occurs in the gauge section. The single yarns were then tested at three strain rates of 3.3×10-5, 3.3×10-3, and 0.33 s-1. The tensile strength, maximum strain, and Young's modulus were determined from the measured stress-strain curves and compared with the values from literature; the results showed these tensile properties of single yarn depend on strain rate over the range tested.

  3. 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...

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

    NASA Technical Reports Server (NTRS)

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

    1979-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

    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.

  6. The Single Group with Nearly Equivalent Tests (SiGNET) Design for Equating Very Small Volume Multiple-Choice Tests. Research Report. ETS RR-11-31

    ERIC Educational Resources Information Center

    Grant, Mary C.

    2011-01-01

    The "single group with nearly equivalent tests" (SiGNET) design proposed here was developed to address the problem of equating scores on multiple-choice test forms with very small single-administration samples. In this design, the majority of items in each new test form consist of items from the previous form, and the new items that were

  7. An evaluation of horizontal recirculation using single-well tests, pumping tests, tracer tests, and the colloidal borescope

    SciTech Connect

    Korte, N.; Kearl, P.M.; Siegrist, R.L.; Muck, M.T.; Schlosser, R.M.

    2000-12-31

    Extensive hydrodynamic testing was performed as part of a program to evaluate horizontal recirculation as a means of removing contaminants from thin, interbedded aquifers. Two test sites, each containing a pair of horizontal recirculation wells, were evaluated using various hydraulic tests. Results of these evaluations showed that ground water was intercepted more than 100 feet beyond the wells, and that the hydraulic gradient increased by more than two orders of magnitude. Aquifer heterogeneity, however, controlled the efficiency and uniformity of ground water flow. Heterogeneity was assessed with a variety of techniques. Bromide tracer tests and the colloidal borescope provided the most useful data. For example, at an uncontaminated site, the leading edge of the bromide tracer traversed the 100 feet between the injection and extraction wells in 21 hours, and the peak bromide concentration was observed in 2.6 days, compared with the four days predicted by a pumping test. The resulting maximum velocity calculation was consistent with measurements made with the borescope in preferential flow zones. Data obtained from a highly contaminated location indicated that assessments of aquifer heterogeneity are further complicated by the presence of DNAPL. Very low flow occurred in a highly contaminated zone, despite the fact that lithologic descriptions indicated that this region contained permeable sand and gravel.

  8. Scale Model Test and Transient Analysis of Steam Injector Driven Passive Core Injection System for Innovative-Simplified Nuclear Power Plant

    NASA Astrophysics Data System (ADS)

    Ohmori, Shuichi; Narabayashi, Tadashi; Mori, Michitsugu

    A steam injector (SI) is a simple, compact and passive pump and also acts as a high-performance direct-contact compact heater. This provides SI with capability to serve also as a direct-contact feed-water heater that heats up feed-water by using extracted steam from turbine. Our technology development aims to significantly simplify equipment and reduce physical quantities by applying "high-efficiency SI", which are applicable to a wide range of operation regimes beyond the performance and applicable range of existing SIs and enables unprecedented multistage and parallel operation, to the low-pressure feed-water heaters and emergency core cooling system of nuclear power plants, as well as achieve high inherent safety to prevent severe accidents by keeping the core covered with water (a severe accident-free concept). This paper describes the results of the scale model test, and the transient analysis of SI-driven passive core injection system (PCIS).

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

    SciTech Connect

    Webber, R.C.; Khabiboulline, T.; Madrak, R.; Nicol, T.; Ristori, L.; Soyars, W.; Wagner, R.; /Fermilab

    2010-09-01

    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 Q{sub ext} 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.

  10. A single stage adiabatic demagnetization refrigerator for testing X-ray microcalorimeters

    NASA Astrophysics Data System (ADS)

    Barbera, Marco; Artale, Maria Antonella; Candia, Roberto; Collura, Alfonso; Di Cicca, Gaspare; Perinati, Emanuele; Serio, Manlio; Serio, Salvatore; Varisco, Salvatore; Silver, Eric; Bandler, Simon R.

    2004-09-01

    A single stage Adiabatic Demagnetization Refrigerator (ADR), has been set-up at the X-ray Astronomy Calibration and Testing (XACT) facility of INAF - Osservatorio Astronomico di Palermo G.S. Vaiana, for the development and testing of cryogenic X-ray detectors for laboratory and astrophysical applications. The ADR allows to cool detectors at temperatures below 40 mK and to maintain them at constant operating temperature for many hours. We describe the design and construction of the ADR and present test results and performances.

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

    SciTech Connect

    Bhatia, P.K.

    1995-01-31

    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.

  12. Statistical searches for microlensing events in large, non-uniformly sampled time-domain surveys: A test using palomar transient factory data

    SciTech Connect

    Price-Whelan, Adrian M.; Agüeros, Marcel A.; Fournier, Amanda P.; Street, Rachel; Ofek, Eran O.; Covey, Kevin R.; Levitan, David; Sesar, Branimir; Laher, Russ R.; Surace, Jason

    2014-01-20

    Many photometric time-domain surveys are driven by specific goals, such as searches for supernovae or transiting exoplanets, which set the cadence with which fields are re-imaged. In the case of the Palomar Transient Factory (PTF), several sub-surveys are conducted in parallel, leading to non-uniform sampling over its ∼20,000 deg{sup 2} footprint. While the median 7.26 deg{sup 2} PTF field has been imaged ∼40 times in the R band, ∼2300 deg{sup 2} have been observed >100 times. We use PTF data to study the trade off between searching for microlensing events in a survey whose footprint is much larger than that of typical microlensing searches, but with far-from-optimal time sampling. To examine the probability that microlensing events can be recovered in these data, we test statistics used on uniformly sampled data to identify variables and transients. We find that the von Neumann ratio performs best for identifying simulated microlensing events in our data. We develop a selection method using this statistic and apply it to data from fields with >10 R-band observations, 1.1 × 10{sup 9} light curves, uncovering three candidate microlensing events. We lack simultaneous, multi-color photometry to confirm these as microlensing events. However, their number is consistent with predictions for the event rate in the PTF footprint over the survey's three years of operations, as estimated from near-field microlensing models. This work can help constrain all-sky event rate predictions and tests microlensing signal recovery in large data sets, which will be useful to future time-domain surveys, such as that planned with the Large Synoptic Survey Telescope.

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

    SciTech Connect

    Liu, T.-J

    2002-01-15

    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.

  14. Experimental results of single screw mechanical tests: a follow-up to SAND2005-6036.

    SciTech Connect

    Lee, Sandwook; Lee, Kenneth L.; Korellis, John S.; McFadden, Sam X.

    2006-08-01

    The work reported here was conducted to address issues raised regarding mechanical testing of attachment screws described in SAND2005-6036, as well as to increase the understanding of screw behavior through additional testing. Efforts were made to evaluate fixture modifications and address issues of interest, including: fabrication of 45{sup o} test fixtures, measurement of the frictional load from the angled fixture guide, employment of electromechanical displacement transducers, development of a single-shear test, and study the affect of thread start orientation on single-shear behavior. A286 and 302HQ, No.10-32 socket-head cap screws were tested having orientations with respect to the primary loading axis of 0{sup 0}, 45{sup o}, 60{sup o}, 75{sup o} and 90{sup o} at stroke speeds 0,001 and 10 in/sec. The frictional load resulting from the angled screw fixture guide was insignificant. Load-displacement curves of A286 screws did not show a minimum value in displacement to failure (DTF) for 60{sup o} shear tests. Tests of 302HQ screws did not produce a consistent trend in DTF with load angle. The effect of displacement rate on DTF became larger as shear angle increased for both A286 and 302HQ screws.

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

    SciTech Connect

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

    1999-07-01

    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.

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

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

    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

    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.

  19. Single event upset suspectibility testing of the Xilinx Virtex II FPGA

    NASA Technical Reports Server (NTRS)

    Carmichael, C.; Swift, C.; Yui, G.

    2002-01-01

    Heavy ion testing of the Xilinx Virtex II was conducted on the configuration, block RAM and user flip flop cells to determine their static single-event upset susceptibility using LETs of 1.2 to 60 MeVcm^2/mg. A software program specifically designed to count errors in the FPGA was used to reveal L1/e, values (the LET at which the cross section is l/e times the saturation cross-section) and single-event functional-interrupt failures.

  20. Tracer Tests in a Fractured Dolomite: 3. Analysis of Mass Transfer in Single-Well Injection-Withdrawal Tests

    SciTech Connect

    Haggerty, R.; Fleming, S.W.; Meigs, L.C.; McKenna, S.A.

    1999-03-04

    We investigated multiple-rate diffusion as a possible explanation for observed behavior in a suite of single-well injection-withdrawal (SWIW) tests conducted in a fractured dolomite. We first investigated the ability of a conventional double-porosity model and a multirate diffusion model to explain the data. This revealed that the multirate diffusion hypothesis/model is most consistent with all available data, and is the only model to date that is capable of matching each of the recovery curves entirely. Second, we studied the sensitivity of the SWIW recovery curves to the distribution of diffusion rate coefficients and other parameters. We concluded that the SWIW test is very sensitive to the distribution of rate coefficients, but is relatively insensitive to other flow and transport parameters such as advective porosity and dispersivity. Third, we examined the significance of the constant double-log late-time slopes ({minus}2. 1 to {minus}2.8), which are present in several data sets. The observed late-time slopes are significantly different than would be predicted by either conventional double-porosity or single-porosity media, and are found to be a distinctive feature of multirate diffusion under SWIW test conditions. Fourth, we found that the estimated distributions of diffusion rate coefficients are very broad, with the distributions spanning a range of at least 3.6 to 5.7 orders of magnitude.

  1. Exploring the efficacy of paternity and kinship testing based on single nucleotide polymorphisms.

    PubMed

    Mo, Shao-Kang; Liu, Ya-Cheng; Wang, Sheng-Qi; Bo, Xiao-Chen; Li, Zhen; Chen, Ying; Ni, Ming

    2016-05-01

    Short tandem repeats (STRs) are conventional genetic markers typically used for paternity and kinship testing. As supplementary markers of STRs, single nucleotide polymorphisms (SNPs) have less discrimination power but broader applicability to degraded samples. The rapid improvement of next-generation sequencing (NGS) and multiplex amplification technologies also make it possible now to simultaneously identify dozens or even hundreds of SNP loci in a single pool. However, few studies have been endeavored to kinship testing based on SNP loci. In this study, we genotyped 90 autosomal human identity SNP loci with NGS, and investigated their testing efficacies based on the likelihood ratio model in eight pedigree scenarios involving paternity, half/full-sibling, uncle/nephew, and first-cousin relationships. We found that these SNPs might be sufficient to discriminate paternity and full-sibling, but impractical for more distant relatives such as uncle and cousin. Furthermore, we conducted an in silico study to obtain the theoretical tendency of how testing efficacy varied with increasing number of SNP loci. For each testing battery in a given pedigree scenario, we obtained distributions of logarithmic likelihood ratio for both simulated relatives and unrelated controls. The proportion of the overlapping area between the two distributions was defined as a false testing level (FTL) to evaluate the testing efficacy. We estimated that 85, 127, 491, and 1,858 putative SNP loci were required to discriminate paternity, full-sibling, half-sibling/uncle-nephew, and first-cousin (FTL, 0.1%), respectively. To test a half-sibling or nephew, an additional uncle relative could be included to decrease the required number of putative SNP loci to ∼320 (FTL, 0.1%). As a systematic computation of paternity and kinship testing based only on SNPs, our results could be informative for further studies and applications on paternity and kinship testing using SNP loci. PMID:26952733

  2. Testing a new automated single ring infiltrometer for Beerkan infiltration experiments

    NASA Astrophysics Data System (ADS)

    Di Prima, Simone; Lassabatère, Laurent; Angulo-Jaramillo, Rafael; Bagarello, Vincenzo; Iovino, Massimo

    2015-04-01

    The Beerkan method along with BEST algorithms is an alternative technique to conventional laboratory or field measurements for rapid and low-cost estimation of soil hydraulic properties. The Beerkan method is simple to conduct but requires an operator to pour known volumes of water through the ring and can be time-consuming. To alleviate this need, a new cheap infiltrometer equipped with a data acquisition system, allowing automation of Beerkan infiltration experiments, was recently designed and is presented in a companion paper. Yet, it has never been tested against a wide range of experimental conditions (soils, initial water saturation, etc.). In this paper, we tested the automated infiltrometer with the aim to validate its applicability to the Beerkan infiltration experiment under several experimental circumstances. In addition, we assessed the accuracy of BEST methods on the data obtained with the infiltrometer for the estimation of saturated soil hydraulic conductivity and sorptivity. For this purpose, we used both analytically generated and real experimental data. The analytically generated data simulate infiltration experiments carried out with the infiltrometer on five contrasting soils from UNSODA database and different initial water contents. The total volume of water to be infiltrated and the volume increments are fixed by the infiltrometer characteristics. Then, inverse analysis of the analytically generated data was performed using the three available BEST algorithms to derive saturated soil hydraulic conductivity and sorptivity that were compared to the reference values. The results of the analytical assessment showed that the infiltrometer along with BEST methods could lead to accurate estimates in most cases thus validating the design of the studied infiltrometer and its combination with BEST algorithms. Some soils (mostly loam) and some hydric conditions (high initial water contents) may lead to misestimate soil properties or failure of BEST algorithms according to numerical results. In these cases, the failures are due to the fact that steady state is not properly reached or the transient state is not properly described (not enough points in the transient state). Finally, the infiltrometer was tested in different soil types. All experiments were carried in an infiltration basin located in the pumping well filed of Crépieux-Charmy, which provides drinking water for the Lyon metropolitan area. Water infiltration experiments were conducted on the subsoil, the layer of sand embedded at surface, either clean or clogged. Experiments and analysis with BEST algorithms proved efficient to pinpoint the decrease in hydraulic conductivity due to clogging. The experiments showed that the automatic data collection increases measurement speeds and allows for more efficient data handling and analysis.

  3. Evidence of Multi-Process Matrix Diffusion in a Single Fracturefrom a Field Tracer Test

    SciTech Connect

    Zhou, Quanlin; Liu, Hui-Hai; Bodvarsson, Gudmundur; Molz, Fred J.

    2005-06-11

    Compared to values inferred from laboratory tests on matrix cores, many field tracer tests in fractured rock have shown enhanced matrix diffusion coefficient values (obtained using a single-process matrix-diffusion model with a homogeneous matrix diffusion coefficient). To investigate this phenomenon, a conceptual model of multi-process matrix diffusion in a single-fracture system was developed. In this model, three matrix diffusion processes of different diffusion rates were assumed to coexist: (1) diffusion into stagnant water and infilling materials within fractures, (2) diffusion into a degraded matrix zone, and (3) further diffusion into an intact matrix zone. The validity of the conceptual model was then demonstrated by analyzing a unique tracer test conducted using a long-time constant-concentration injection. The tracer-test analysis was conducted using a numerical model capable of tracking the multiple matrix-diffusion processes. The analysis showed that in the degraded zone, a diffusion process with an enhanced diffusion rate controlled the steep rising limb and decay-like falling limb in the observed breakthrough curve, whereas in the intact matrix zone, a process involving a lower diffusion rate affected the long-term middle platform of slowly increasing tracer concentration. The different matrix-diffusion-coefficient values revealed from the field tracer test are consistent with the variability of matrix diffusion coefficient measured for rock cores with different degrees of fracture coating at the same site. By comparing to the matrix diffusion coefficient calibrated using single-process matrix diffusion, we demonstrated that this multi-process matrix diffusion may contribute to the enhanced matrix-diffusion-coefficient values for single-fracture systems at the field scale.

  4. Negligible shift of 3Ag- potential in longer-chain carotenoids as revealed by a single persistent peak of 3Ag-?1Ag- stimulated emission followed by 3Ag-?1Ag- transient-absorption

    NASA Astrophysics Data System (ADS)

    Li, Chunyong; Miki, Takeshi; Kakitani, Yoshinori; Koyama, Yasushi; Nagae, Hiroyoshi

    2007-12-01

    Upon excitation of lycopene, anhydrorhodovibrin or spirilloxanthin to the 1Bu+(0) state, stimulated emission followed by transient-absorption was observed as a single peak with the 3Ag-(0) energy that had been determined by measurement of resonance-Raman excitation profiles. This observation was explained in terms of negligible shift of the 3Ag- potential, in reference to the 1Ag- potential, where only the 3Ag-(?)?1Ag-(?) emission and the 3Ag-(?)?1Ag-(?) absorption become allowed during the vibrational relaxation of ? = 2 ? 1 ? 0, starting from the 3Ag-(2) level generated by diabatic internal conversion from the 1Bu+(0) level, in anhydrorhodovibrin, for example.

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

    NASA Astrophysics Data System (ADS)

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

    2014-03-01

    We test experimentally the quantum "paradox" proposed by L. Hardy [Phys. Rev. Lett. 71, 1665 (1993), 10.1103/PhysRevLett.71.1665] 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 noncontextuality, 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.

  6. Interpretation of transmissivity estimates from single-well pumping aquifer tests

    USGS Publications Warehouse

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

    2006-01-01

    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.

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

    SciTech Connect

    Yakovlev, V.; Solyak, N.; Wu, G.; Ge, M.; Gonin, I.; Khabiboulline, T.; Ozelis, J.; Rowe, A.; Avrakhov, P.; Kanareykin, A.; Rathke, J.

    2010-11-04

    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.

  8. Pollution emissions from single swirl-can combustor modules at parametric test conditions

    NASA Technical Reports Server (NTRS)

    Mularz, E. J.; Wear, J. D.; Verbulecz, P. W.

    1975-01-01

    Exhaust pollutant emissions were measured from single swirl-can combustor modules operating over a pressure range of 69 to 276 N/sq cm (100 to 400 psia), over a fuel-air ratio range of 0.01 to 0.04, at an inlet air temperature of 733 K (860 F), and at a constant reference velocity of 23.2 m/sec). Many swirl-can module designs were evaluated; the 11 most promising designs exhibited oxides of nitrogen emission levels lower than that from conventional gas-turbine combustors. Although these single module test results are not necessarily indicative of the performance characteristics of a large array of modules, the results are very promixing and offer a number of module designs that should be tested in a full combustor.

  9. Testing of a single-polarity piezoresistive three-dimensional stress-sensing chip

    NASA Astrophysics Data System (ADS)

    Gharib, H. H.; Moussa, W. A.

    2013-09-01

    A new piezoresistive stress-sensing rosette is developed to extract the components of the three-dimensional (3D) stress tensor using single-polarity (n-type) piezoresistors. This paper presents the testing of a micro-fabricated sensing chip utilizing the developed single-polarity rosette. The testing is conducted using a four-point bending of a chip-on-beam to induce five controlled stress components, which are analyzed both numerically and experimentally. Numerical analysis using finite element analysis is conducted to study the levels of the induced stress components at three rosette-sites and the levels of the stress field non-uniformities, and to simulate the extracted stress components from the sensing rosette. The experimental analysis applied tensile and compressive loads over three rosette-sites at different load increments. The experimentally extracted stress components show good linearity with the applied load and values close to the numerical model.

  10. Test results of the infrared single-mode fiber for the DARWIN mission

    NASA Astrophysics Data System (ADS)

    Cheng, Lun K.; Faber, Anne-Jans; Gielesen, Wim; Boussard-Pledel, Catherine; Houizot, Patrick; Lucas, Jacques; Pereira Do Carmo, Joao

    2005-08-01

    Nulling interferometry is the baseline technique for the DARWIN planet finding mission of the European Space Agency. Using this technique it will be possible to cancel, by destructive interference, the light from the bright star and look directly at its surrounding planets and eventually discover life on them. To achieve this goal wavefront errors need to be reduced to a very high degree in order to achieve the required nulling quality. Such a high wavefront quality can only be achieved with adequate wavefront filtering measures. Single mode fibers in general have excellent mode filtering capabilities, but they were not recently available for the broad infrared wavelength region of Darwin (4-20 um). Within an ESA technology development project, TNO has designed and tested an infrared single mode fiber based on chalcogenide glasses that has been manufactured by the University of Rennes. Several tests are carried out to characterize the materials used and the IR single mode fiber. Far field intensity distribution measurement at 10.6 um reveals the single mode operation of the manufactured fiber. Influence of coating, length, light coupling and bending of the fiber are also investigated.

  11. Single well surfactant test to evaluate surfactant floods using multi tracer method

    DOEpatents

    Sheely, Clyde Q.

    1979-01-01

    Data useful for evaluating the effectiveness of or designing an enhanced recovery process said process involving mobilizing and moving hydrocarbons through a hydrocarbon bearing subterranean formation from an injection well to a production well by injecting a mobilizing fluid into the injection well, comprising (a) determining hydrocarbon saturation in a volume in the formation near a well bore penetrating formation, (b) injecting sufficient mobilizing fluid to mobilize and move hydrocarbons from a volume in the formation near the well bore, and (c) determining the hydrocarbon saturation in a volume including at least a part of the volume of (b) by an improved single well surfactant method comprising injecting 2 or more slugs of water containing the primary tracer separated by water slugs containing no primary tracer. Alternatively, the plurality of ester tracers can be injected in a single slug said tracers penetrating varying distances into the formation wherein the esters have different partition coefficients and essentially equal reaction times. The single well tracer method employed is disclosed in U.S. Pat. No. 3,623,842. This method designated the single well surfactant test (SWST) is useful for evaluating the effect of surfactant floods, polymer floods, carbon dioxide floods, micellar floods, caustic floods and the like in subterranean formations in much less time and at much reduced cost compared to conventional multiwell pilot tests.

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

    NASA Technical Reports Server (NTRS)

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

    2002-01-01

    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).

  13. Performance evaluation of pyrochlore ceramic waste forms by single pass flow through testing

    NASA Astrophysics Data System (ADS)

    Zhao, P.; Bourcier, W. L.; Esser, B. K.; Shaw, H. F.

    2000-07-01

    Titanate-based ceramic waste forms for the disposal of nuclear wastes have been the subjects of numerous studies over the past decades. In order to assess the performance of this ceramic in a potential Yucca Mountain high-level waste (HLW) repository, it is necessary to understand the kinetics and mechanisms of corrosion of the ceramic under repository conditions. To this end, we are conducting single pass flow-through (SPFT) dissolution tests on ceramics relevant to Pu disposition.

  14. Feasibility of loophole-free nonlocality tests with a single photon

    NASA Astrophysics Data System (ADS)

    Chaves, Rafael; Brask, Jonatan Bohr

    2011-12-01

    Recently, much interest has been directed toward designing setups that achieve realistic loss thresholds for decisive tests of local realismin particular in the optical regime. We analyze the feasibility of such Bell tests based on a W state shared between multiple parties, which can be realized, for example, by a single photon shared between spatial modes. We develop a general error model to obtain thresholds for the efficiencies required to violate local realism and also consider two concrete optical-measurement schemes.

  15. Feasibility of loophole-free nonlocality tests with a single photon

    SciTech Connect

    Chaves, Rafael; Brask, Jonatan Bohr

    2011-12-15

    Recently, much interest has been directed toward designing setups that achieve realistic loss thresholds for decisive tests of local realism--in particular in the optical regime. We analyze the feasibility of such Bell tests based on a W state shared between multiple parties, which can be realized, for example, by a single photon shared between spatial modes. We develop a general error model to obtain thresholds for the efficiencies required to violate local realism and also consider two concrete optical-measurement schemes.

  16. High gradient test of the HINS SSR1 single spoke resonator

    SciTech Connect

    Gonin, I.; Khabibouline, T.; Lanfranco, G.; Mukherjee, A.; Ozelis, JH.; Ristori, L.; Sergatskov, A.; Wagner, R.; Webber, R.; /Fermilab

    2008-09-01

    Eighteen {beta} = 0.21 superconducting single spoke resonators comprise the first state in the cold section of the 8-GeV H{sup -} Linac for Fermilab's proposed Project X. After Buffered Chemical Polishing and High Pressure Rinse, one resonator has undergone high gradient RF testing at 2.0-4.5 K in the Vertical Test Stand at Fermilab. They present measurements of the surface resistance as a function of temperature and the quality factor as a function of accelerating field. The resonator reached an accelerating field of 18.0 MV/m.

  17. Testing of plain and fibrous concrete single cavity prestressed concrete reactor vessel models

    SciTech Connect

    Oland, C.B.

    1985-01-01

    Two single-cavity prestressed concrete reactor vessel (PCRV) models were fabricated and tested to failure to demonstrate the structural response and ultimate pressure capacity of models cast from high-strength concretes. Concretes with design compressive strengths in excess of 70 MPa (10,000 psi) were developed for this investigation. One model was cast from plain concrete and failed in shear at the head region. The second model was cast from fiber reinforced concrete and failed by rupturing the circumferential prestressing at the sidewall of the structure. The tests also demonstrated the capabilities of the liner system to maintain a leak-tight pressure boundary. 3 refs., 4 figs.

  18. Allison engine testing CMSX-4{reg_sign} single crystal turbine blades and vanes

    SciTech Connect

    Burkholder, P.S.; Thomas, M.C.; Frasier, D.J.; Whetstone, J.R.; Harris, K.; Erickson, G.L.; Sikkenga, S.L.; Eridon, J.M.

    1995-05-01

    A team approach utilizing simultaneous engineering has been used to develop CMSX-4 turbine airfoil components. CMSX-4 is a nickel-base single crystal superalloy containing 3% (wt) rhenium and a high 71% volume fraction of coherent {gamma}{prime} precipitate strengthening phase. The high level of balanced properties determined by extensive laboratory evaluation has been confirmed during engine testing the Allison AE 2100 and AE 301X engines, with the post-test condition of the components, including advanced Castcool{trademark} vane segments, being excellent. Also uncooled vane segments in CMSX-4 have exceeded engineering expectations.

  19. Novel Application of Single-Well Tracer Tests to Evaluate Hydraulic Stimulation Effectiveness

    SciTech Connect

    G. M. Shook; Gopi Nalla

    2005-09-01

    This paper presents a graphical method by which one can identify the number of fractures and their permeability distribution in the near-well region from single-well tracer tests. The method is an extension of tracer analysis methods developed previously to estimate flow geometry and relies on caluclating the relative fluid velocity from F-__ plots. A number of numerical examples show that high flow zones (fractures) are readily identified from the derivatives of an F-___ curve. The method can be used in evaluating well stimulation efforts by conducting a tracer test before and after the stimulation and comparing the velocity distributions.

  20. Tank Tests of Models of Floats for Single-float Seaplanes First Series.

    NASA Technical Reports Server (NTRS)

    Parkinson, J B

    1936-01-01

    Large models of the Mark V and Mark VI floats used for single float seaplanes (National Advisory Committee for Aeronautics (NACA) models 41-A and 41-B, respectively) were tested in the NACA tank to provide general test data for typical single floats and a basis for possible improvements of their form. The resistance of model 41-B was greater than that of model 41-A, either when free to trim or at the best trim angle for each. The resistance of model 35-B (a pointed step hull tested free to trim) was less than either of the models at the hump speed, greater at intermediate planing speeds, and less at the speeds and loads near get-away, although the spray was generally worse owing to the absence of transverse flare. The results of the fixed-trim tests of model 41-A were cross plotted to obtain data at the angle for zero trimming moment and at the best trim angle. The trims assumed by models 41-A and 41-B, when tested free to trim, were found to be excessive at the hump speed. The corresponding trim of model 35-B was found to be approximately 3 degrees lower because of the lower angle of afterbody keel used in this model, and the maximum hump resistance was 15 percent lower.

  1. Study of the comminution characteristics of coal by single particle breakage test device

    SciTech Connect

    Sahoo, R.

    2005-09-01

    Single-particle breakage tests of South Blackwater and Ensham coal from the Bowen Basin area in Queensland were conducted by a computer-monitored twin-pendulum device to measure the energy utilization pattern of the breakage particles. Three particle sizes (-16.0+13.2mm, -13.2+11.2mm, -11.2+9.5mm) of each coal were tested by a pendulum device at five input energy levels to measure the specific comminution energy. When particles were tested at constant input energy, the variation of comminution energy between the same size broken particles of Ensham coal was minimal, because Ensham coal is a softer and higher friability coal, which absorbs more input energy than harder coal during breakage tests. For different particle sizes, the specific comminution energy increases linearly with the input energy and the fineness of the breakage products increases with the specific comminution energy. The size distribution graphs are curved but approach linearity in the finer region. At a constant input energy, the twin pendulum breakage product results show that the fineness of the products increases with decrease in particle size and South Blackwater coal produced finer products than the Ensham coal. The t-curves are the family of size distribution curves, which can describe the product size distribution of the breakage particles during single-particle breakage tests.

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

    SciTech Connect

    Schock, Alfred

    1994-06-01

    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.

  3. Detection of acute changes in circulating troponin in the setting of transient stress test-induced myocardial ischaemia using an ultrasensitive assay: results from TIMI 35

    PubMed Central

    Sabatine, Marc S.; Morrow, David A.; de Lemos, James A.; Jarolim, Petr; Braunwald, Eugene

    2009-01-01

    Aims To determine whether an ultrasensitive assay can permit quantification of changes in circulating cardiac troponin (Tn) in the setting of stress test-induced myocardial ischaemia. Methods and results Blood samples were obtained before, immediately after, and 2 and 4 h after stress testing with nuclear perfusion imaging in 120 patients. Troponin was measured using commercial assays as well as with a novel, ultrasensitive cardiac TnI assay with a limit of detection of 0.2 pg/mL. Using the ultrasensitive assay, TnI was detectable in all patients before stress testing (median 4.4 pg/mL, interquartile range 3.18.6 pg/mL). By 4 h, troponin levels were unchanged in patients without ischaemia, whereas circulating levels had increased by a median of 1.4 pg/mL (24% increase) in patients with mild ischaemia (P = 0.002) and by 2.1 pg/mL (40% increase) in patients with moderate-to-severe ischaemia (P = 0.0006). In contrast, changes in troponin levels across patients in different ischaemic categories were indistinguishable using commercial troponin assays. When added to clinical factors, a >1.3 pg/mL increase in TnI using the ultrasensitive assay was an independent predictor of ischaemia (odds ratio 3.54, P = 0.007). Conclusion Transient stress test-induced myocardial ischaemia is associated with a quantifiable increase in circulating troponin that is detectable with a novel, ultrasensitive TnI assay. PMID:18997177

  4. Impact of typical steady-state conditions and transient conditions on flow ripple and its test accuracy for axial piston pump

    NASA Astrophysics Data System (ADS)

    Xu, Bing; Hu, Min; Zhang, Junhui

    2015-09-01

    The current research about the flow ripple of axial piston pump mainly focuses on the effect of the structure of parts on the flow ripple. Therein, the structure of parts are usually designed and optimized at rated working conditions. However, the pump usually has to work in large-scale and time-variant working conditions. Therefore, the flow ripple characteristics of pump and analysis for its test accuracy with respect to variant steady-state conditions and transient conditions in a wide range of operating parameters are focused in this paper. First, a simulation model has been constructed, which takes the kinematics of oil film within friction pairs into account for higher accuracy. Afterwards, a test bed which adopts Secondary Source Method is built to verify the model. The simulation and tests results show that the angular position of the piston, corresponding to the position where the peak flow ripple is produced, varies with the different pressure. The pulsating amplitude and pulsation rate of flow ripple increase with the rise of pressure and the variation rate of pressure. For the pump working at a constant speed, the flow pulsation rate decreases dramatically with the increasing speed when the speed is less than 27.78% of the maximum speed, subsequently presents a small decrease tendency with the speed further increasing. With the rise of the variation rate of speed, the pulsating amplitude and pulsation rate of flow ripple increase. As the swash plate angle augments, the pulsating amplitude of flow ripple increases, nevertheless the flow pulsation rate decreases. In contrast with the effect of the variation of pressure, the test accuracy of flow ripple is more sensitive to the variation of speed. It makes the test accuracy above 96.20% available for the pulsating amplitude of pressure deviating within a range of 6% from the mean pressure. However, with a variation of speed deviating within a range of 2% from the mean speed, the attainable test accuracy of flow ripple is above 93.07%. The model constructed in this research proposes a method to determine the flow ripple characteristics of pump and its attainable test accuracy under the large-scale and time-variant working conditions. Meanwhile, a discussion about the variation of flow ripple and its obtainable test accuracy with the conditions of the pump working in wide operating ranges is given as well.

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

    NASA Technical Reports Server (NTRS)

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

    1971-01-01

    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.

  6. Nuclear radiation test of a D flip-flop IC using a single-board microcomputer

    SciTech Connect

    Lim, T.S.; Martin, R.L.; Hughes, H.L.

    1987-01-01

    The design of a microcomputer-controlled electronic circuit and its use in evaluating the effects of nuclear radiation on a 4013 CMOS D flip-flop (FF) integrated circuit (IC) are described. The IC undergoing testing is attached to a DUT (device under test) board, which is enclosed in a metal container. The container is then lowered to the cobalt 60 radiation source located at the bottom of a 15-ft-deep pool filled to the top with water. The gamma-ray radiation test setup is schematically shown. The in-source test board containing the D FF IC is attached to an 8085-based single-board microcomputer, SDK-85, by a 30-ft multiconductor cable. Doses of gamma-ray radiation from the cobalt 60 are applied in steps at increasing quantities until the D FF IC, which is tested between doses, begins to malfunction. The leakage current and the propagation delay time are measured between doses. An 8085 assembly language program is used for functional test of the IC. The software design and the radiation testing procedure are discussed in detail.

  7. A rapid antimicrobial susceptibility test based on single-cell morphological analysis.

    PubMed

    Choi, Jungil; Yoo, Jungheon; Lee, Mincheol; Kim, Eun-Geun; Lee, Ji Soo; Lee, Seungok; Joo, Seik; Song, Sang Hoon; Kim, Eui-Chong; Lee, Jung Chan; Kim, Hee Chan; Jung, Yong-Gyun; Kwon, Sunghoon

    2014-12-17

    A rapid antibiotic susceptibility test (AST) is desperately needed in clinical settings for fast and appropriate antibiotic administration. Traditional ASTs, which rely on cell culture, are not suitable for urgent cases of bacterial infection and antibiotic resistance owing to their relatively long test times. We describe a novel AST called single-cell morphological analysis (SCMA) that can determine antimicrobial susceptibility by automatically analyzing and categorizing morphological changes in single bacterial cells under various antimicrobial conditions. The SCMA was tested with four Clinical and Laboratory Standards Institute standard bacterial strains and 189 clinical samples, including extended-spectrum ?-lactamase-positive Escherichia coli and Klebsiella pneumoniae, imipenem-resistant Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, and vancomycin-resistant Enterococci from hospitals. The results were compared with the gold standard broth microdilution test. The SCMA results were obtained in less than 4 hours, with 91.5% categorical agreement and 6.51% minor, 2.56% major, and 1.49% very major discrepancies. Thus, SCMA provides rapid and accurate antimicrobial susceptibility data that satisfy the recommended performance of the U.S. Food and Drug Administration. PMID:25520395

  8. Aero engine test experience with CMSX-4{reg_sign} alloy single-crystal turbine blades

    SciTech Connect

    Fullagar, K.P.L.; Broomfield, R.W.; Hulands, M.; Harris, K.; Erickson, G.L.; Sikkenga, S.L.

    1996-04-01

    A team approach involving a turbine engine company (Rolls-Royce), its single-crystal casting facilities, and a superalloy developer and ingot manufacturer (Cannon-Muskegon), utilizing the concepts of simultaneous engineering, has been used to develop CMSX-4 alloy successfully for turbine blade applications. CMSX-4 alloy is a second-generation nickel-base single-crystal superalloy containing 3 percent (wt) rhenium (Re) and 70 percent volume fraction of the coherent {gamma}{prime} precipitate strengthening phase. The paper details the single-crystal casting process and heat treatment manufacturing development for turbine blades in CMSX-4 alloy. Competitive single-crystal casting yields are being achieved in production and extensive vacuum heat treatment experience confirms CMSX-4 alloy to have a practical production solution heat treat/homogenization ``window.`` The creep-rupture data-base on CMSX-4 alloy now includes 325 data points from 17 heats including 3,630 kg (8,000 lb) production size heats. An appreciable portion of this data was machined-from-blade (MFB) properties, which indicate turbine blade component capabilities based on single-crystal casting process, component configuration, and heat treatment. The use of hot isostatic pressing (HIP) has been shown to eliminate single-crystal casting micropores, which along with the essential absence of {gamma}/{gamma}{prime} eutectic phase, carbides, stable oxide, nitride and sulfide inclusions, results in remarkably high mechanical fatigue properties, with smooth and particularly notched specimens. The Re addition has been shown not only to benefit creep and mechanical fatigue strength, but also bare oxidation, hot corrosion, and coating performance. The high level of balanced properties determined by extensive laboratory evaluation has been confirmed during engine testing of the Rolls-Royce Pegasus turbofan.

  9. Infrastructure Development of Single Cell Testing Capability at A0 Facility

    SciTech Connect

    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

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

    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 Vortrge und Poster. Schriftenreihe der DGG, Heft 78, S. 192.

  11. Testing The Performance Of A Single-Phase Autotransformer On MATLAB/Simulink

    NASA Astrophysics Data System (ADS)

    Panu, Mihai Gheorghe; Viorel, Alina Cristina

    2015-07-01

    This paper presents a virtual laboratory for testing a single-phase autotransformer using MATLAB Simulink environment. The model is implemented according to a practical laboratory used at electric machines' discipline for the undergraduate level in electrical engineering. The model presented herein is a copy of a practical experiment for an autotransformer made in the test laboratory. The rating of the autotransformer is taken to be 2 kVA, 230/0230 V, and it was set at a transformer ratio of 1.5. The used model is a linear one and run for a pure resistive load test. In the same time, it was aimed the simulation accuracy as it was used a linear model, neglecting the magnetic saturation effect.

  12. Single-dose Intravenous Toxicology Testing of Daebohwalryeok Pharmcopuncture in Sprague-Dawley Rats

    PubMed Central

    Sun, Seung-Ho; Park, Sunju; Jeong, Jong-Jin; Lee, Kwang-Ho; Yu, Jun-Sang; Seo, Hyung-Sik; Kwon, Ki-Rok

    2015-01-01

    Objectives: The aims of the study were to test the single-dose intravenous toxicity of Daebohwalryeok pharmacopuncture (DHRP) in Sprague-Dawley (SD) rats and to estimate the crude lethal dose. Methods: The experiments were conducted at Biotoxtech Co., a Good Laboratory Practice (GLP) laboratory, according to the GLP regulation and were approved by the Institutional Animal Care and Use Committee of Biotoxtech Co. (Approval no: 110156). The rats were divided into three groups: DHRP was injected into the rats in the two test groups at doses of 10 mL/kg and 20 mL/kg, respectively, and normal saline solution was injected into the rats in the control group. Single doses of DHRP were injected intravenously into 6 week old SD rats (5 male and 5 female rats per group). General symptoms were observed and weights were measured during the 14 day observation period after the injection. After the observation period, necropsies were done. Then, histopathological tests were performed. Weight data were analyzed with a one-way analysis of variance (ANOVA) by using statistical analysis system (SAS, version 9.2). Results: No deaths and no statistical significant weight changes were observed for either male or female SD rats in either the control or the test groups during the observation period. In addition, no treatment related general symptoms or necropsy abnormalities were observed. Histopathological results showed no DHRP related effects in the 20 mL/kg DHRP group for either male or female rats. Conclusion: Under the conditions of this study, the results from single-dose intravenous injections of DHRP showed that estimated lethal doses for both male and female rats were above 20 mL/kg. PMID:26120487

  13. 42 CFR 84.1145 - Silica dust test; non-powered single-use dust respirators; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Silica dust test; non-powered single-use dust... RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1145 Silica dust test; non-powered single-use...

  14. 42 CFR 84.1145 - Silica dust test; non-powered single-use dust respirators; minimum requirements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 1 2014-10-01 2014-10-01 false Silica dust test; non-powered single-use dust... RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1145 Silica dust test; non-powered single-use...

  15. 42 CFR 84.1145 - Silica dust test; non-powered single-use dust respirators; minimum requirements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 1 2012-10-01 2012-10-01 false Silica dust test; non-powered single-use dust... RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1145 Silica dust test; non-powered single-use...

  16. 42 CFR 84.1145 - Silica dust test; non-powered single-use dust respirators; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 1 2011-10-01 2011-10-01 false Silica dust test; non-powered single-use dust... RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1145 Silica dust test; non-powered single-use...

  17. 42 CFR 84.1145 - Silica dust test; non-powered single-use dust respirators; minimum requirements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 1 2013-10-01 2013-10-01 false Silica dust test; non-powered single-use dust... RESPIRATORY PROTECTIVE DEVICES Dust, Fume, and Mist; Pesticide; Paint Spray; Powered Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1145 Silica dust test; non-powered single-use...

  18. Transient characteristics of rocket turbopumps

    NASA Astrophysics Data System (ADS)

    Shimura, Takashi; Watanabe, Mitsuo

    Transient characteristics of high-speed, high-pressure cryogenic turbopumps for rocket engines were examined experimentally by starting and stopping several rocket turbopumps rapidly by gas turbine drive. Aspects of transient characteristics studied were instantaneous pump head coefficient and pump efficiency, cavitation growth in the inducer during rapid acceleration, effects of the starting mode related to the propulsion system mission, and transient behavior of a self-balancing type axial thrust balancing system. Based on the test results, the feasibility of definite starting modes for the LE-5 turbopump was confirmed and the self-balancing type axial thrust balancing system for the LE-7 LOX turbopump was completed.

  19. Single-Neuron Axonal Pathfinding under Geometric Guidance: Low-Dose-Methylmercury Developmental Neurotoxicity Test

    PubMed Central

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

    2014-01-01

    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

  20. 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)

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

    1979-01-01

    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.

  1. Design, implementation, and testing of a single axis levitation system for the suspension of a platform.

    PubMed

    Banerjee, Subrata; Prasad, Dinkar; Pal, Jayanta

    2007-04-01

    This paper describes the design and implementation of a single axis DC attraction type suspension system, where a platform (vehicle structure) of around 14 kg mass is made to remain suspended at the desired operating gap under a ferromagnetic guide-way. The prototype has four electromagnetic actuators of attraction type and four inductive gap sensors, all located at the corners of the platform. The four actuators are controlled independently through four identical controllers, and the stable levitation of the platform is achieved through the single input and single output (SISO) control of each air-gap. The emphasis of this work is on the design and development of the switched mode power amplifier cum controller unit for the four actuators. The proposed single switch-based power circuit simplifies the overall hardware, and it can be extended to any number of magnet-coils. A cascade lead compensation control scheme utilizing an inner current loop and outer position loop has been designed and implemented for the stabilization of such a highly unstable and strongly nonlinear system. The prototype has been successfully tested, and stable levitation was demonstrated with the desired operating gap. PMID:17350630

  2. Preliminary comparison of the transient effects of single versus multiple q-switched doubled-neodymium laser pulses. Final report, July-November 1986

    SciTech Connect

    Previc, F.H.

    1987-09-01

    A comparison between the effects of single and multiple laser pulse trains of equivalent energy was performed. Visual evoked potentials (VEPS) recorded bipolarly from the visual cortex of two rhesus monkeys in response to a counterphasing grating were used to assess the magnitude of the visual loss following four types of exposures: single and multiple pulses with total energies equal to 50% and 500% of the maximum permissible exposure (MPE) standard for humans. The results showed that the effects of a series of laser flashes presented within 200ms are similar to those of a single laser flash whose energy is equivalent to the cumulative energy of the multiple-pulse exposure.

  3. Reducing carbonyl emissions from a heavy-duty diesel engine at US transient cycle test by use of paraffinic/biodiesel blends

    NASA Astrophysics Data System (ADS)

    Yuan, Chung-Shin; Lin, Yuan-Chung; Tsai, Cheng-Hsien; Wu, Chia-Chieh; Lin, Yu-Sheng

    2009-12-01

    Formaldehyde and acetaldehyde are toxic carcinogens so their reductions in diesel-engine emissions are desirable. This study investigated emissions of carbonyl compounds (CBCs) from an HDDE (heavy-duty diesel engine) at US transient cycle test, using five test fuels: premium diesel fuel (D100), P100 (100% palm-biodiesel), P20 (20% palm-biodiesel + 80% premium diesel fuel), PF80P20 (80% paraffinic fuel + 20% palm-biodiesel), and PF95P05 (95% paraffinic fuel + 5% palm-biodiesel). Experimental results indicate that formaldehyde was the major carbonyl in the exhaust, accounting for 70.1-76.2% of total CBC concentrations for all test fuels. In comparison with D100 (172 mg BHP -1 h -1), the reductions of formaldehyde and acetaldehyde emission factor for P100, P20, PF80P20, and PF95P05 were (-16.8%, -61.8%), (-10.0%, -39.0%), (21.3%, 1.10%), and (31.1%, 19.5%), respectively. Using P100 and P20 instead of D100 in the HDDE increased CBC concentrations by 14.5% and 3.28%, respectively, but using PF80P20 and PF95P05 significantly reduced CBC concentrations by 30.3% and 23.7%, respectively. Using P100 and P20 instead of D100 (2867 ton yr -1) in the HDDE increased CBC emissions by 240 and 224 ton yr -1, respectively, but using PF80P20, and PF95P05 instead of D100 in the HDDE decreased CBC emissions by 711 and 899 ton yr -1, respectively. The above results indicate that the wide usage of paraffinic-palmbiodiesel blends as alternative fuels could protect the environment.

  4. A cross-bridge based model of force depression: Can a single modification address both transient and steady-state behaviors?

    PubMed

    Corr, David T; Herzog, Walter

    2016-03-21

    Force depression (FD), the reduction of isometric force following active shortening, is a phenomenon of skeletal muscle that has received significant attention in biomechanical and physiological literature, yet the mechanisms underlying FD remain unknown. Recent experiments identified a slower rate of force redevelopment with increasing amounts of steady-state FD, suggesting that FD may be caused, at least in part, by a decrease in cross-bridge binding rate (Corr and Herzog, 2005; Koppes et al., 2014). Herein, we develop a cross-bridge based model of FD in which the binding rate function, f, decreases with the mechanical work performed during shortening. This modification incorporates a direct relationship between steady-state FD and muscle mechanical work (Corr and Herzog, 2005; Herzog et al., 2000; Kosterina et al., 2008), and is consistent with a proposed mechanism attributing FD to stress-induced inhibition of cross-bridge attachments (Herzog, 1998; Maréchal and Plaghki, 1979). Thus, for an increase in mechanical work, the model should predict a slower force redevelopment (decreased attachment rate) to a more depressed steady-state force (fewer attached cross-bridges), and a reduction in contractile element stiffness (Ford et al., 1981). We hypothesized that since this modification affects the cross-bridge kinetics, a corresponding model would be able to account for both transient and steady-state FD behaviors. Comparisons to prior experiments (Corr and Herzog, 2005; Herzog et al., 2000; Kosterina et al., 2008) show that both steady-state and transient aspects of FD, as well as the relationship of FD with respect to speed and amplitude of shortening, are well captured by this model. Thus, this relatively simple cross-bridge based model of FD lends support to a mechanism involving the inhibition of cross-bridge binding, and indicates that cross-bridge kinetics may play a critical role in FD. PMID:26928777

  5. The Single Intradermal Cervical Comparative Test Interferes with Johnes Disease ELISA Diagnostics

    PubMed Central

    Kennedy, Aideen E.; Da Silva, Ana T.; Byrne, Noel; Govender, Rodney; MacSharry, John; OMahony, Jim; Sayers, Riona G.

    2014-01-01

    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 Johnes 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 prevalences 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. PMID:25429289

  6. Transient receptor potential cation channel A1 (TRPA1) mediates changes in heart rate variability following a single exposure to acrolein in mice

    EPA Science Inventory

    The data show that a single exposure to acrolein causes autonomic imbalance in mice through the TRPA1 sensor and subsequent cardiac dysfunction. Human and animal studies have shown that short-term air pollution exposure causes...

  7. A comparison of single-cycle versus multiple-cycle proof testing strategies

    NASA Technical Reports Server (NTRS)

    Hudak, S. J., Jr.; Mcclung, R. C.; Bartlett, M. L.; Fitzgerald, J. H.; Russell, D. A.

    1990-01-01

    An evaluation of single-cycle and multiple-cycle proof testing (MCPT) strategies for SSME components is described. Data for initial sizes and shapes of actual SSME hardware defects are analyzed statistically. Closed-form estimates of the J-integral for surface flaws are derived with a modified reference stress method. The results of load- and displacement-controlled stable crack growth tests on thin IN-718 plates with deep surface flaws are summarized. A J-resistance curve for the surface-cracked configuration is developed and compared with data from thick compact tension specimens. The potential for further crack growth during large unload/reload cycles is discussed, highlighting conflicting data in the literature. A simple model for ductile crack growth during MCPT based on the J-resistance curve is used to study the potential effects of key variables. The projected changes in the crack size distribution during MCPT depend on the interactions between several key parameters, including the number of proof cycles, the nature of the resistance curve, the initial crack size distribution, the component boundary conditions (load vs. displacement control), and the magnitude of the applied load or displacement. The relative advantages of single-cycle and multiple-cycle proof testing appear to be specific, therefore, to individual component geometry, material, and loading.

  8. 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

    B. R. Orr

    1999-11-01

    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).

  9. Testing the effect of transient Plio-Pleistocene barriers in monsoonal Australo-Papua: did mangrove habitats maintain genetic connectivity in the Black Butcherbird?

    PubMed

    Kearns, Anna M; Joseph, Leo; Omland, Kevin E; Cook, Lyn G

    2011-12-01

    Changes in climate and sea level are hypothesized to have promoted the diversification of biota in monsoonal Australia and New Guinea by causing repeated range disjunctions and restricting gene flow between isolated populations. Using a multilocus (one mtDNA locus, five nuclear introns) phylogeographic approach, we test whether populations of the mangrove and rainforest restricted Black Butcherbird (Cracticus quoyi) have diverged across several geographic barriers defined a priori for this region. Phylogeographic structure and estimates of divergence times revealed Plio-Pleistocene divergences and long-term restricted gene flow of populations on either side of four major geographic barriers between and within Australia and New Guinea. Overall, our data are consistent with the hypothesis that mesic-adapted species did not disperse across the open dry woodlands and grasslands that dominated the transient palaeo-landbridges during the Plio-Pleistocene despite the presence of mangrove forests that might have acted as dispersal corridors for mesic-adapted species. Our study offers one of the first multilocus perspectives on the impact of changes in climate and sea level on the population history of widespread species with disjunct ranges in Australia and New Guinea. PMID:22060632

  10. Design and cold-air test of single-stage uncooled turbine with high work output

    NASA Technical Reports Server (NTRS)

    Moffitt, T. P.; Szanca, E. M.; Whitney, W. J.; Behning, F. P.

    1980-01-01

    A solid version of a 50.8 cm single stage core turbine designed for high temperature was tested in cold air over a range of speed and pressure ratio. Design equivalent specific work was 76.84 J/g at an engine turbine tip speed of 579.1 m/sec. At design speed and pressure ratio, the total efficiency of the turbine was 88.6 percent, which is 0.6 point lower than the design value of 89.2 percent. The corresponding mass flow was 4.0 percent greater than design.

  11. Gravitational independence of single-breath washout tests in recumbent dogs

    NASA Technical Reports Server (NTRS)

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

    1988-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2007-12-01

    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.

  13. Dynamical study of the transport properties of ?-Mo4O11 single crystals by use of the photoinduced transient thermoelectric effect

    NASA Astrophysics Data System (ADS)

    Sasaki, M.; Tai, G. X.; Tamura, S.; Inoue, M.

    1993-03-01

    The pulsed-laser-induced transient thermoelectric effect (TTE) and the static transport properties (resistivity, Hall coefficient, magnetoresistance, and thermopower) of a quasi-two-dimensional ?-Mo4O11 crystal have been measured over the time range 50 ns-2 ms and temperature range 4.2-300 K. The observed TTE voltages decay exponentially with time, showing relaxation processes with multiple relaxation times ?i (i=1-5) for thermal diffusions of photogenerated carriers (electrons and holes), from which we can evaluate the corresponding carrier mobilities ?i. The temperature dependences of both dynamic and static transport quantities show anomalies around the characteristic temperatures Tc1=105 K and Tc2=35 K; Tc1 is the well-known charge-density-wave (CDW) transition temperature, but for the latter no definitive x-ray evidence for a CDW transition is reported. However, using our dynamic data and the existing two-dimensional tight-binding model, together with our proposed nesting model of the Fermi surfaces and the CDW-related modifications of the electron and hole bands at Tc1 and Tc2, we have self-consistently calculated the temperature dependence of the dc transport quantities, in satisfactory agreement with the experiments.

  14. Summary of Group Development and Testing for Single Shell Tank Closure at Hanford

    SciTech Connect

    Harbour, John, R.

    2005-04-28

    This report is a summary of the bench-scale and large scale experimental studies performed by Savannah River National Laboratory for CH2M HILL to develop grout design mixes for possible use in producing fill materials as a part of Tank Closure of the Single-Shell Tanks at Hanford. The grout development data provided in this report demonstrates that these design mixes will produce fill materials that are ready for use in Hanford single shell tank closure. The purpose of this report is to assess the ability of the proposed grout specifications to meet the current requirements for successful single shell tank closure which will include the contracting of services for construction and operation of a grout batch plant. The research and field experience gained by SRNL in the closure of Tanks 17F and 20F at the Savannah River Site was leveraged into the grout development efforts for Hanford. It is concluded that the three Hanford grout design mixes provide fill materials that meet the current requirements for successful placement. This conclusion is based on the completion of recommended testing using Hanford area materials by the operators of the grout batch plant. This report summarizes the regulatory drivers and the requirements for grout mixes as tank fill material. It is these requirements for both fresh and cured grout properties that drove the development of the grout formulations for the stabilization, structural and capping layers.

  15. Single element injector cold flow testing for STME swirl coaxial injector element design

    NASA Technical Reports Server (NTRS)

    Hulka, J.; Schneider, J. A.

    1993-01-01

    An oxidizer-swirled coaxial element injector is being investigated for application in the Space Transportation Main Engine (STME). Single element cold flow experiments were conducted to provide characterization of the STME injector element for future analysis, design, and optimization. All tests were conducted to quiescent, ambient backpressure conditions. Spray angle, circumferential spray uniformity, dropsize, and dropsize distribution were measured in water-only and water/nitrogen flows. Rupe mixing efficiency was measured using water/sucrose solution flows with a large grid patternator for simple comparative evaluation of mixing. Factorial designs of experiment were used for statistical evaluation of injector geometrical design features and propellant flow conditions on mixing and atomization. Increasing the free swirl angle of the liquid oxidizer had the greatest influence on increasing the mixing efficiency. The addition of gas assistance had the most significant effect on reducing oxidizer droplet size parameters and increasing droplet size distribution. Increasing the oxidizer injection velocity had the greatest influence for reducing oxidizer droplet size parameters and increasing size distribution for non-gas assisted flows. Single element and multi-element subscale hot fire testing are recommended to verify optimized designs before committing to the STME design.

  16. Single element injector cold flow testing for STME swirl coaxial injector element design

    NASA Astrophysics Data System (ADS)

    Hulka, J.; Schneider, J. A.

    1993-06-01

    An oxidizer-swirled coaxial element injector is being investigated for application in the Space Transportation Main Engine (STME). Single element cold flow experiments were conducted to provide characterization of the STME injector element for future analysis, design, and optimization. All tests were conducted to quiescent, ambient backpressure conditions. Spray angle, circumferential spray uniformity, dropsize, and dropsize distribution were measured in water-only and water/nitrogen flows. Rupe mixing efficiency was measured using water/sucrose solution flows with a large grid patternator for simple comparative evaluation of mixing. Factorial designs of experiment were used for statistical evaluation of injector geometrical design features and propellant flow conditions on mixing and atomization. Increasing the free swirl angle of the liquid oxidizer had the greatest influence on increasing the mixing efficiency. The addition of gas assistance had the most significant effect on reducing oxidizer droplet size parameters and increasing droplet size distribution. Increasing the oxidizer injection velocity had the greatest influence for reducing oxidizer droplet size parameters and increasing size distribution for non-gas assisted flows. Single element and multi-element subscale hot fire testing are recommended to verify optimized designs before committing to the STME design.

  17. Transient global amnesia.

    PubMed

    Arena, Julieta E; Rabinstein, Alejandro A

    2015-02-01

    Transient global amnesia (TGA) is a clinical syndrome characterized by the sudden onset of anterograde amnesia (the inability to encode new memories), accompanied by repetitive questioning, sometimes with a retrograde component, lasting up to 24 hours, without compromise of other neurologic functions. Herein, we review current knowledge on the epidemiology, pathophysiology, clinical diagnosis, and prognosis of TGA. For this review, we conducted a literature search of PubMed, with no date limitations, using the following search terms (or combinations of them): transient global amnesia, etiology, pathophysiology, venous hypertension, migraine, magnetic resonance imaging, computed tomography, electroencephalography, prognosis, and outcome. We also reviewed the bibliography cited in the retrieved articles. Transient global amnesia is a clinical diagnosis, and recognition of its characteristic features can avoid unnecessary testing. Several pathophysiologic mechanisms have been proposed (venous insufficiency, arterial ischemia, and migrainous or epileptic phenomena), but none of them has been proved to consistently explain cases of TGA. Brain imaging may be considered and electroencephalography is recommended when episodes are brief and recurrent, but otherwise no investigations are necessary in most cases. Data on long-term prognosis are limited, but available information suggests that the relapse rate is low, the risk of stroke and seizures is not considerably increased, and cognitive outcome is generally good. PMID:25659242

  18. Stress transfer in microdroplet tensile test: PVC-coated and uncoated Kevlar-29 single fiber

    NASA Astrophysics Data System (ADS)

    Zhenkun, Lei; Quan, Wang; Yilan, Kang; Wei, Qiu; Xuemin, Pan

    2010-11-01

    The single fiber/microdroplet tensile test is applied for evaluating the interfacial mechanics between a fiber and a resin substrate. It is used to investigate the influence of a polymer coating on a Kevlar-29 fiber surface, specifically the stress transfer between the fiber and epoxy resin in a microdroplet. Unlike usual tests, this new test ensures a symmetrical axial stress on the embedded fiber and reduces the stress singularity that appears at the embedded fiber entry. Using a homemade loading device, symmetrical tensile tests are performed on a Kevlar-29 fiber with or without polyvinylchloride (PVC) coating, the surface of which is in contact with two epoxy resin microdroplets during curing. Raman spectra on the embedded fiber are recorded by micro-Raman Spectroscopy under different strain levels. Then they are transformed to the distributions of fiber axis stress based on the relationship between stress and Raman shift. The Raman results reveal that the fiber axial stresses increase with the applied loads, and the antisymmetric interfacial shear stresses, obtained by a straightforward balance of shear-to-axial forces argument, lead to the appearance of shear stress concentrations at a distance to the embedded fiber entry. The load is transferred from the outer fiber to the embedded fiber in the epoxy microdroplet. As is observed by scanning electronic microscopy (SEM), the existence of a flexible polymer coating on the fiber surface reduces the stress transfer efficiency.

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

    PubMed Central

    Baron, Ralf; Maier, Christoph; Tlle, Thomas R.; Treede, Rolf-Detlef; Berthele, Achim; Faltraco, Frank; Flor, Herta; Gierthmhlen, Janne; Haenisch, Sierk; Huge, Volker; Magerl, Walter; Maihfner, Christian; Richter, Helmut; Rolke, Roman; Scherens, Andrea; eyler, Nurcan; Ufer, Mike; Wasner, Gunnar; Zhu, Jihong; Cascorbi, Ingolf

    2011-01-01

    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 nucleotide polymorphisms and their impact on somatosensory abnormalities in neuropathic pain patients. Within the German Research Network on Neuropathic Pain (Deutscher Forscbungsverbund Neuropathischer Schmerz) 371 neuropathic pain patients were phenotypically characterized using standardized quantitative sensory testing. Pyrosequencing was employed to determine a total of eleven single nucleotide polymorphisms in transient receptor potential channel genes of the neuropathic pain patients and a cohort of 253 German healthy volunteers. Associations of quantitative sensory testing parameters and single nucleotide polymorphisms between and within groups and subgroups, based on sensory phenotypes, were analyzed. Single nucleotide polymorphisms frequencies did not differ between both the cohorts. However, in neuropathic pain patients transient receptor potential ankyrin 1 710G>A (rs920829, E179K) was associated with the presence of paradoxical heat sensation (p?=?0.03), and transient receptor potential vanilloid 1 1911A>G (rs8065080, I585V) with cold hypoalgesia (p?=?0.0035). Two main subgroups characterized by preserved (1) and impaired (2) sensory function were identified. In subgroup 1 transient receptor potential vanilloid 1 1911A>G led to significantly less heat hyperalgesia, pinprick hyperalgesia and mechanical hypaesthesia (p?=?0.006, p?=?0.005 and p<0.001) and transient receptor potential vanilloid 1 1103C>G (rs222747, M315I) to cold hypaesthesia (p?=?0.002), but there was absence of associations in subgroup 2. In this study we found no evidence that genetic variants of transient receptor potential channels are involved in the expression of neuropathic pain, but transient receptor potential channel polymorphisms contributed significantly to the somatosensory abnormalities of neuropathic pain patients. PMID:21468319

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

    ERIC Educational Resources Information Center

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

    2014-01-01

    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

  1. Test Analysis Correlation of the Single Stringer Bending Tests for the Space Shuttle ET-137 Intertank Stringer Crack Investigation

    NASA Technical Reports Server (NTRS)

    Phillips, Dawn R.; Saxon, Joseph B.; Wingate, Robert J.

    2012-01-01

    On November 5, 2010, Space Shuttle mission STS-133 was scrubbed due to a hydrogen leak at the Ground Umbilical Carrier Plate (GUCP). After the scrub, a crack in the foam thermal protection system (TPS) was observed on the External Tank (ET) near the interface between the liquid oxygen (LOX) tank and the Intertank. When the damaged foam was removed, two 9-in. long cracks were found on the feet of Intertank stringer S7-2, and the stringer failure was the cause of the TPS crack. An investigation was conducted to determine the root cause of the cracks, establish a remedy/repair for the stringers, and provide flight rationale for the damaged tank, ET-137. The Space Transportation System (STS) Super Lightweight ET (SLWT) is comprised of two propellant tanks (an aft liquid hydrogen (LH2) tank and a forward LOX tank) and an Intertank. The Intertank serves as the structural connection between the two propellant tanks and also functions to receive and distribute all thrust loads from the solid rocket boosters . The Intertank is a stiffened cylinder structure consisting of eight mechanically joined panels (two integrally-stiffened, machined thrust panels to react the booster loads and six stringer-stiffened skin panels). There are one main ring frame, four intermediate ring frames, and forward and aft flange chords that mate to the respective propellant tanks.. The skin/stringer panels utilize external hat-section stringers that are mechanically attached with rivets along most of their length and with specialty fasteners, such as GP Lockbolts and Hi-Loks, at the forward and aft ends where the stringers attach to the flange chords. During the STS-133 Intertank stringer crack investigation, cracks were found on a total of five stringers. All of the cracks were at the LOX end, in the feet of the stringers, and near the forward fasteners (GP Lockbolts). Video of tanking for the November 5 launch attempt was used to determine that the TPS failure, and thus the stringer failure, occurred as the LOX liquid level crossed the LOX tank / Intertank interface ring frame. Hence, cryogenically-induced displacements were suspected as a contributing cause of the stringer cracks. To study the behavior of Intertank stringers subjected to similar displacements, static load tests of individual stringers, colloquially known as "single stringer bending tests" were performed. Approximately thirty stringers were tested, many of which were cut from the partially completed Intertank for what would have been ET-139. In addition to the tests, finite element (FE) analyses of the test configuration were also performed. In this paper, the FE analyses and test-analysis correlation for stringer test S6-8 are presented. Stringer S6-8 is a "short chord" configuration with no doubler panels.

  2. Fractal analysis of pressure transients in the Geysers Geothermal Field

    SciTech Connect

    Acuna, J.A.; Ershaghi, I.; Yortsos, Y.C.

    1992-01-01

    The conventionally accepted models for the interpretation of pressure transient tests in naturally fractured reservoirs usually involve simplistic assumptions regarding the geometry and transport properties of the fractured medium. Many single well tests in this type of reservoirs fail to show the predicted behavior for dual or triple porosity or permeability systems and cannot be explained by these models. This paper describes the application of a new model based on a fractal interpretation of the fractured medium. The approach, discussed elsewhere [2], [6], is applied to field data from The Geysers Geothermal Field. The objective is to present an alternative interpretation to well tests that characterizes the fractured medium in a manner more consistent with other field evidence. The novel insight gained from fractal geometry allows the identification of important characteristics of the fracture structure that feeds a particular well. Some simple models are also presented that match the field transient results.

  3. Single-Crystal NiAl-X Alloys Tested for Hot Corrosion

    NASA Technical Reports Server (NTRS)

    Nesbitt, James A.

    1999-01-01

    Single-crystal nickel aluminide (NiAl) has been investigated extensively throughout the last several years as a potential structural material in aero-gas turbine engines. The attractive features of NiAl in comparison to Ni-base superalloys include a higher melting point, lower density, higher thermal conductivity, and excellent oxidation resistance. However, NiAl suffers from a lack of ductility and fracture toughness at low temperatures and a low creep strength at high temperatures. Alloying additions of hafnium (Hf), gallium (Ga), titanium (Ti), and chromium (Cr) have each shown some benefit to the mechanical properties over that of the binary alloy. However, the collective effect of these alloying additions on the environmental resistance of NiAl-X was unclear. Hence, the present study was undertaken to examine the hot corrosion behavior of these alloys. A companion study examined the cyclic oxidation resistance of these alloys. Several single-crystal NiAl-X alloys (where X is Hf, Ti, Cr, or Ga) underwent hot corrosion testing in a Mach 0.3 burner rig at the NASA Lewis Research Center. Samples were tested for up to 300 1-hr cycles at a temperature of 900 C. It was found that increasing the Ti content from 1 to 5 at.% degraded the hot corrosion behavior. This decline in the behavior was reflected in high weight gains and large corrosion mound formation during testing (see the figures). However, the addition of 1 to 2 at.% Cr to alloys containing 4 to 5 at.% Ti appeared to greatly reduce the susceptibility of these alloys to hot corrosion attack and negated the deleterious effect of the increased Ti addition.

  4. Using latent class analysis to estimate the test characteristics of the γ-interferon test, the single intradermal comparative tuberculin test and a multiplex immunoassay under Irish conditions.

    PubMed

    Clegg, Tracy A; Duignan, Anthony; Whelan, Clare; Gormley, Eamonn; Good, Margaret; Clarke, John; Toft, Nils; More, Simon J

    2011-07-01

    Considerable effort has been devoted to improving the existing diagnostic tests for bovine tuberculosis (single intradermal comparative tuberculin test [SICTT] and γ-interferon assay [γ-IFN]) and to develop new tests. Previously, the diagnostic characteristics (sensitivity, specificity) have been estimated in populations with defined infection status. However, these approaches can be problematic as there may be few herds in Ireland where freedom from infection is guaranteed. We used latent class models to estimate the diagnostic characteristics of existing (SICTT and γ-IFN) and new (multiplex immunoassay [Enferplex-TB]) diagnostic tests under Irish field conditions where true disease status was unknown. The study population consisted of herds recruited in areas with no known TB problems (2197 animals) and herds experiencing a confirmed TB breakdown (2740 animals). A Bayesian model was developed, allowing for dependence between SICTT and γ-IFN, while assuming independence from the Enferplex-TB test. Different test interpretations were used for the analysis: SICTT (standard and severe interpretation), γ-IFN (a single interpretation), and a range of interpretations for the Enferplex-TB (level-1 [high sensitivity interpretation] to level-5 [high specificity interpretation]). The sensitivity and specificity (95% posterior credibility intervals; 95% PCI) of SICTT[standard] relative to Enferplex-TB[level-1] and γ-IFN were 52.9-60.8% and 99.2-99.8%, respectively. Equivalent estimates for γ-IFN relative to Enferplex-TB[level-1] and SICTT were 63.1-70.1% and 86.8-89.4%, respectively. Sensitivity of Enferplex-TB[level-1] (95% PCI: 64.8-71.9%) was superior to the SICTT[standard], and specificity of the Enferplex-TB[level-5] was superior to γ-IFN (95% PCI: 99.6-100.0%). These results provide robust measures of sensitivity and specificity under field conditions in Ireland and suggest that the Enferplex-TB test has the potential to improve on current diagnostics for TB infection in cattle. The extent of that potential will be assessed in further studies. PMID:21470800

  5. A Compendium of Recent Optocoupler Radiation Test Data

    NASA Technical Reports Server (NTRS)

    Label, K. A.; Kniffin, S. D.; Reed, R. A.; Kim, H. S.; Wert, J. L.; Oberg, D. L.; Normand, E.; Johnston, A. H.; Lum, G. K.; Koga, R.; Day, John H. (Technical Monitor)

    2000-01-01

    We present a compendium of optocoupler radiation test data including neutron, proton and heavy ion Displacement Damage (DD), Single Event Transients (SET) and Total Ionizing Dose (TID). Proton data includes ionizing and non-ionizing damage mechanisms.

  6. Predictions and observations of the thermal hydrological conditions in the Single Heater Test

    NASA Astrophysics Data System (ADS)

    Tsang, Y. W.; Birkholzer, J. T.

    1999-05-01

    The Single Heater Test (SHT) is one of two in-situ thermal tests included in the site characterization program for the potential underground nuclear waste repository at Yucca Mountain. Coupled thermal-hydrological-mechanical-chemical processes in the fractured rock mass around the heater were monitored by numerous sensors emplaced among 30 boreholes. Periodic active testing of cross-hole radar tomography, neutron logging, electrical resistivity tomography, and interference air permeability tests probed the change of moisture content in the rock mass. Thermal-hydrological processes in the SHT have been simulated using a 3-D numerical model and compared to the monitored data. The good agreement between the temperature data and simulated results indicates that the thermal-hydrological responses of the SHT in the 9 months of heating are well-represented by the coupled thermal-hydrological numerical model. The dominant heat transfer process is by conduction and the signature of vapor and liquid counter flow is subtle in the temperature data. The simulated result of a dry-out zone of about 1 m (at the end of the heating phase) around the heater hole, and a condensation zone of increased liquid saturation outside of the dry-out zone, is consistent with the radar tomography and air permeability data. Tomography data and post-test laboratory measurements indicate that the moisture content is larger below than above the heater horizon, suggesting gravity drainage of condensate in the fractures. Model studies show that gravity drainage occurs in simulations using the dual permeability conceptual model, but is absent in the effective-continuum model, where matrix and fractures are required to be in thermodynamic equilibrium at all times.

  7. Estimating and Testing Pleiotropy of Single Genetic Variant for Two Quantitative Traits

    PubMed Central

    Zhang, Qunyuan; Feitosa, Mary; Borecki, Ingrid B.

    2014-01-01

    Along with the accumulated data of genetic variants and biomedical phenotypes in the genome era, statistical identification of pleiotropy is of growing interest for dissecting and understanding genetic correlations between complex traits. We proposed a novel method for estimating and testing pleiotropic effect of a genetic variant on two quantitative traits. Based on a covariance decomposition and estimation, our method quantifies pleiotropy as the portion of between-trait correlation explained by the same genetic variant. Unlike most multiple-trait methods that assess potential pleiotropy (i.e., whether a variant contributes to at least one trait), our method formulates a statistic that tests exact pleiotropy (i.e., whether a variant contributes to both of two traits). We developed two approaches (a regression approach and a bootstrapping approach) for such test and investigated their statistical properties, in comparison with other potential pleiotropy test methods. Our simulation shows that the regression approach produces correct p-values under both the complete null (i.e., a variant has no effect on both two traits) and the incomplete null (i.e., a variant has effect on only one of two traits), but requires large sample sizes to achieve a good power, when the bootstrapping approach has a better power and produces conservative p-values under the complete null. We demonstrate our method for detecting exact pleiotropy using a real GWAS dataset. Our method provides an easy-to-implement tool for measuring, testing and understanding the pleiotropic effect of a single variant on the correlation architecture of two complex traits. PMID:25044106

  8. Evaluation of testing strategies to identify infected animals at a single round of testing within dairy herds known to be infected with Mycobacterium avium ssp. paratuberculosis.

    PubMed

    More, S J; Cameron, A R; Strain, S; Cashman, W; Ezanno, P; Kenny, K; Fourichon, C; Graham, D

    2015-08-01

    As part of a broader control strategy within herds known to be infected with Mycobacterium avium ssp. paratuberculosis (MAP), individual animal testing is generally conducted to identify infected animals for action, usually culling. Opportunities are now available to quantitatively compare different testing strategies (combinations of tests) in known infected herds. This study evaluates the effectiveness, cost, and cost-effectiveness of different testing strategies to identify infected animals at a single round of testing within dairy herds known to be MAP infected. A model was developed, taking account of both within-herd infection dynamics and test performance, to simulate the use of different tests at a single round of testing in a known infected herd. Model inputs included the number of animals at different stages of infection, the sensitivity and specificity of each test, and the costs of testing and culling. Testing strategies included either milk or serum ELISA alone or with fecal culture in series. Model outputs included effectiveness (detection fraction, the proportion of truly infected animals in the herd that are successfully detected by the testing strategy), cost, and cost-effectiveness (testing cost per true positive detected, total cost per true positive detected). Several assumptions were made: MAP was introduced with a single animal and no management interventions were implemented to limit within-herd transmission of MAP before this test. In medium herds, between 7 and 26% of infected animals are detected at a single round of testing, the former using the milk ELISA and fecal culture in series 5 yr after MAP introduction and the latter using fecal culture alone 15 yr after MAP introduction. The combined costs of testing and culling at a single round of testing increases with time since introduction of MAP infection, with culling costs being much greater than testing costs. The cost-effectiveness of testing varied by testing strategy. It was also greater at 5 yr, compared with 10 or 15 yr, since MAP introduction, highlighting the importance of early detection. Future work is needed to evaluate these testing strategies in subsequent rounds of testing as well as accounting for different herd dynamics and different levels of herd biocontainment. PMID:26074225

  9. Transient and steady-state selection in the striatal microcircuit

    PubMed Central

    Tomkins, Adam; Vasilaki, Eleni; Beste, Christian; Gurney, Kevin; Humphries, Mark D.

    2014-01-01

    Although the basal ganglia have been widely studied and implicated in signal processing and action selection, little information is known about the active role the striatal microcircuit plays in action selection in the basal ganglia-thalamo-cortical loops. To address this knowledge gap we use a large scale three dimensional spiking model of the striatum, combined with a rate coded model of the basal ganglia-thalamo-cortical loop, to asses the computational role the striatum plays in action selection. We identify a robust transient phenomena generated by the striatal microcircuit, which temporarily enhances the difference between two competing cortical inputs. We show that this transient is sufficient to modulate decision making in the basal ganglia-thalamo-cortical circuit. We also find that the transient selection originates from a novel adaptation effect in single striatal projection neurons, which is amenable to experimental testing. Finally, we compared transient selection with models implementing classical steady-state selection. We challenged both forms of model to account for recent reports of paradoxically enhanced response selection in Huntington's disease patients. We found that steady-state selection was uniformly impaired under all simulated Huntington's conditions, but transient selection was enhanced given a sufficient Huntington's-like increase in NMDA receptor sensitivity. Thus our models provide an intriguing hypothesis for the mechanisms underlying the paradoxical cognitive improvements in manifest Huntington's patients. PMID:24478684

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

    NASA Technical Reports Server (NTRS)

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

    1996-01-01

    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 semi-elliptical 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 vs. 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.

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

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

    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.

  12. Additive Manufacturing Thermal Performance Testing of Single Channel GRCop-84 SLM Components

    NASA Technical Reports Server (NTRS)

    Garcia, Chance P.; Cross, Matthew

    2014-01-01

    The surface finish found on components manufactured by sinter laser manufacturing (SLM) is rougher (0.013 - 0.0006 inches) than parts made using traditional fabrication methods. Internal features and passages built into SLM components do not readily allow for roughness reduction processes. Alternatively, engineering literature suggests that the roughness of a surface can enhance thermal performance within a pressure drop regime. To further investigate the thermal performance of SLM fabricated pieces, several GRCop-84 SLM single channel components were tested using a thermal conduction rig at MSFC. A 20 kW power source running at 25% duty cycle and 25% power level applied heat to each component while varying water flow rates between 2.1 - 6.2 gallons/min (GPM) at a supply pressure of 550 to 700 psi. Each test was allowed to reach quasi-steady state conditions where pressure, temperature, and thermal imaging data were recorded. Presented in this work are the heat transfer responses compared to a traditional machined OHFC Copper test section. An analytical thermal model was constructed to anchor theoretical models with the empirical data.

  13. Leishmanin skin test in guinea pig with a single purified protein of Leishmania major.

    PubMed

    Khabiri, A R; Bagheri, F; Alimohammadian, M H; Assmar, M; Nadaf, S R

    2005-12-01

    A series of hybridomas was produced by fusion of SP2/0 myeloma cells with spleen cells of mice immunized with Leishmania major (L. major). The reactivity of secreted monoclonal antibodies (mAbs) was evaluated against available leishmanin antigen by enzyme linked immunosorbent assay. Only one hybridoma designated as 7F9 secreted IgG1 mAb which was shown to be reactive with leishmanin. This mAb was further tested against four species of Leishmania (L. donovani, L. tropica, L. infantum, L. major) and a recombinant gp63. Among the four species tested it was shown to be only reactive with promastigotes of L. major. The antigen recognized by this mAb was purified and analyzed from both sonicated and supernatant cultures of L. major by immunoaffinity chromatography and reverse phase high performance liquid chromatography. The purified antigen, which gave a single band of 56kDa on sodium dodecyl sulfate polyacrylamide gel electrophoresis elicited a strong delayed-type hypersensitivity (DTH) reaction in guinea pigs sensitized with L. major. It was almost of the same degree as that produced by leishmanin. These results suggest that an L. major-specific antigen is an alternative as a specific diagnostic skin test reagent, which could lead to a better understanding of the mechanism of DTH in L. major. PMID:16212955

  14. Crash tests of four identical high-wing single-engine airplanes

    NASA Technical Reports Server (NTRS)

    Vaughan, V. L., Jr.; Hayduk, R. J.

    1980-01-01

    Four identical four place, high wing, single engine airplane specimens with nominal masses of 1043 kg were crash tested at the Langley Impact Dynamics Research Facility under controlled free flight conditions. These tests were conducted with nominal velocities of 25 m/sec along the flight path angles, ground contact pitch angles, and roll angles. Three of the airplane specimens were crashed on a concrete surface; one was crashed on soil. Crash tests revealed that on a hard landing, the main landing gear absorbed about twice the energy for which the gear was designed but sprang back, tending to tip the airplane up to its nose. On concrete surfaces, the airplane impacted and remained in the impact attitude. On soil, the airplane flipped over on its back. The crash impact on the nose of the airplane, whether on soil or concrete, caused massive structural crushing of the forward fuselage. The liveable volume was maintained in both the hard landing and the nose down specimens but was not maintained in the roll impact and nose down on soil specimens.

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

    SciTech Connect

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

    2011-07-01

    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.

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

    NASA Technical Reports Server (NTRS)

    Irom, Farokh; Agarwal, Shri G.

    2012-01-01

    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.

  17. Definition of Capabilities Needed for a Single Event Effects Test Facility

    SciTech Connect

    Riemer, Bernie; Gallmeier, Franz X.

    2014-12-01

    The Federal Aviation Administration (FAA) is contemplating new regulations mandating testing of the vulnerability of flight-critical avionics to single event effects (SEE). A limited number of high-energy neutron test facilities currently serve the SEE industrial and institutional research community. The FAA recognizes that existing facilities have insufficient test capacity to meet new demand from such mandates; it desires more flexible irradiation capabilities to test complete, large systems and would like capabilities to address greater concerns for thermal neutrons. For this reason, the FAA funded this study by Spallation Neutron Source (SNS) staff with the ultimate aim of developing options for SEE test facilities using high-energy neutrons at the SNS complex. After an investigation of current SEE test practices and assessment of future testing requirements, three concepts were identified covering a range of test functionality, neutron flux levels, and fidelity to the atmospheric neutron spectrum. The costs and times required to complete each facility were also estimated. SEE testing is generally performed by accelerating the event rate to a point where the effects are still dominated by single events and double event causes of failures are negligible. In practice, acceleration factors of as high as 106 are applicable for component testing, whereas for systems testing acceleration factors of 104 seem to be the upper limit. It is strongly desirable that the irradiation facility be tunable over a large range of high-energy neutron fluxes of 102 - 104 n/cm²/s for systems testing and from 104 - 107 n/cm²/s for components testing. The most capable, most flexible, and highest-test-capacity option is a new stand-alone target station named the High-Energy neutron Test Station (HETS). It is also the most expensive option, with a cost to complete of approximately $100 million. Dual test enclosures would allow for simultaneous testing activity effectively doubling overall test capacity per HETS operating hour. Using about 1 kilowatt (kW) of proton power extracted from the accelerator before injection in the accumulator ring, its operation would be unnoticeable by neutron scattering users at the SNS target station. The H beam laser stripping technique would allow for control of beam power on the HETS target independent from power delivered to the SNS. Large systems with frontal areas of up to 1 x 2 m² could be accommodated with integral high-energy flux values (above 10 megaelectron-volt, or MeV) to at most 104 n/cm²/s; components could also be tested with flux levels to at most 107 n/cm²/s on beam sizes of up to 0.2 x 0.2 m². Selectable moderating material and neutron filters would allow tailoring of the neutron spectrum to user demands; charged particle deflectors could be switched to allow or deflect protons, pions, and muons. It is estimated that HETS would take 5 years to complete after award of contract, including engineering design and construction. Commissioning would take at least another 6 months. Interference with SNS principal operations was not considered in the construction time estimate; connection of the proton transport line and tunnel from the accelerator high energy beam transport (HEBT) and construction around existing site utilities would require careful planning and coordination with beam operations at the SNS. A high-energy (HE) neutron test facility using an available beam line on the SNS target station is a technically and financially attractive option. Inspired by the new ChipIR instrument on the ISIS TS 2 spallation source in the UK, a similar facility could be placed on an unused beam line in the SNS instrument hall [e.g., on beam line 8 (both A and B channels would be needed) or on beam line 10]. The performance would approach that of an HETS (~80%), but it would be operationally more limited, with only a single user at a time. Space is more limited, so the maximum system size would be about half of that in an HETS. Flexibility to tailor the spectrum would be somewhat more limited. While this concept was not as fully developed and characterized, preliminary work indicates very high HE flux levels should be possible, with ample thermal neutrons as well. Flux control would be more difficult than at HETS because proton power on target be whatever the SNS was operating at for neutron scattering. Neutron attenuation devices would have to be employed with as-yet undetermined control resolution. However, no new buildings would be needed, and the necessary utilities are already present in the SNS Experiment Hall. The estimated cost for a beam line option is around $15 million; the time to complete would be 3 years after award of contract, plus at least 6 months for commissioning. Interference of construction activities with SNS operations should be negligible. This option would require negotiation with the Department of Energy Basic Energy Sciences (BES) office -- the primary stakeholder of SNS -- for an application outside the usual scope of neutron scattering sciences. Furthermore, these presently open beam lines are highly desirable locations for proposed neutron scattering instruments and obtaining one of them for an SEE test facility will come only with persuasive and timely arguments to SNS leadership and the DOE BES. The third option is a tunnel extension/target cave facility providing the most basic system-level irradiation capability with minimal flexibility. Again not as well developed a concept as HETS, it would use a laser-stripping technique like an HETS, redirecting protons to a tunnel similar to the initial HETS proton transport tunnel. Indeed, this concept is intended to be upgradable to a full HETS facility. Only a small fraction of a watt of proton power would be used in this basic configuration, though. An uncooled target and primitive shielding arrangement would provide beam on modestly sized systems that must be placed in close proximity to the target. The neutron fluence would be less uniform over the system than with the HETS or the beam line option. A data acquisition room and support area would be located on the ground level; access to the target cave would be via elevator and/or stairway. As a result of the required excavation, new tunnel construction, shielding, data acquisition building, utilities, and other items, the estimated cost is $30 million. The time to complete is expected be more than 3 years; here again construction interference with SNS operations has not been accounted for, but it could have a significant impact.

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

    SciTech Connect

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

    1999-06-01

    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.

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

    NASA Technical Reports Server (NTRS)

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

    1972-01-01

    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.

  20. Single-column model for atmospheric radiation measurement sites: Model development and sensitivity test

    SciTech Connect

    Xu, Q.; Dong, M.

    1995-04-01

    A single-column model (SCM) is constructed by extracting the physical subroutines from the community climate model (CCMI) of the National Center for Atmospheric Research. Using observational data obtained from the Oklahoma Atmospheric Radiation Measurement (ARM) site and the National Weather Services, this SCM will perform diagnostic studies of radiation and cloud parameterizations. So far, the model has been tested with simulated data generated by CCM1 global runs. The global runs provide the SCM with initial and lateral boundary conditions that represent the Oklahoma ARM site. The preliminary results can be summarized as follows: the SCM can produce nearly the same results as the CCM1 if the lateral boundary conditions are precisely given from the spectral forms of representation of boundary fluxes; the SCM results are moderately sensitive to noise in the lateral boundary conditions. The SCM simulated temperature can (or cannot) closely follow the CCM1 global run if the noise in the lateral boundary fluxes is below (or above) 10% of the single level. The representativeness of the lateral boundary conditions seems crucial for the SCM simulations. When the advection term is calculated by using the central finite difference scheme from the gridded (instead of spectral) data produced by the CCM1 run, the SCM simulated temperature can differ significantly from that of the CCM1 global run.

  1. Single-String Integration Test Measurements of the NEXT Ion Engine Plume

    NASA Technical Reports Server (NTRS)

    Snyder, Aaron; Kamhawi, Hani; Patterson, Michael; Britton, Melissa

    2005-01-01

    Measurements were made of a 40 cm ion-thruster plume as part of the single-string-integration-test (SSIT) activity of Phase I of the NASA's Evolutionary Xenon Thruster (NEXT) project. The NEXT ion engine incorporates design improvements that extend NSTAR power levels and efficiencies. During SSIT, an engineering model (EM2) 40 cm engine was operated using an advanced xenon propellant system in combination with either a GRC power console or advanced power processing unit. Integral goals of the single-string phase were to characterize engine performance over the full input power range and to detail thruster operation within the specification of the NEXT throttle table. Plume diagnostics measurements of relative Xe(+) and Xe(++) currents were made using near-field and far-field ExB probes. Planar geometry faraday probes were used to obtain beam current density profiles. This paper reports on the characterization of the EM2 plume over a range of SSIT operating conditions, first with the advanced propellant management system teamed with the GRC power console and then with the power-processing unit.

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

    NASA Astrophysics Data System (ADS)

    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

    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 519300 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.

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

    SciTech Connect

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

    2010-11-01

    The ability to reliably predict flow and transport in fractured porous rock is an essential condition for performance evaluation of geologic (underground) nuclear waste repositories. In this report, a suite of programs (TRIPOLY code) for calculating and analyzing flow and transport in two-dimensional fracture-matrix systems is used to model single-well injection-withdrawal (SWIW) tracer tests. The SWIW test, a tracer test using one well, is proposed as a useful means of collecting data for site characterization, as well as estimating parameters relevant to tracer diffusion and sorption. After some specific code adaptations, we numerically generated a complex fracture-matrix system for computation of steady-state flow and tracer advection and dispersion in the fracture network, along with solute exchange processes between the fractures and the porous matrix. We then conducted simulations for a hypothetical but workable SWIW test design and completed parameter sensitivity studies 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, is also modeled in this study, in two different ways: (1) by increasing the hydraulic aperture for flow in existing fractures and (2) by adding a new set of fractures to the field. The results of all these different tests are analyzed by studying the population of matrix blocks, the tracer spatial distribution, and the breakthrough curves (BTCs) obtained, while performing mass-balance checks and being careful to avoid some numerical mistakes that could occur. This study clearly demonstrates the importance of matrix effects in the solute transport process, with the sensitivity studies illustrating the increased importance of the matrix in providing a retardation mechanism for radionuclides as matrix porosity, diffusion coefficient, or retardation coefficient increase. Interestingly, model results before and after hydrofracking are insensitive to adding more fractures, while slightly more sensitive to aperture increase, making SWIW tests a possible means of discriminating between these two potential hydrofracking effects. Finally, we investigate the possibility of inferring relevant information regarding the fracture-matrix system physical parameters from the BTCs obtained during SWIW testing.

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

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

    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.

  5. Value of a single-tube widal test in diagnosis of typhoid fever in Vietnam.

    PubMed

    Parry, C M; Hoa, N T; Diep, T S; Wain, J; Chinh, N T; Vinh, H; Hien, T T; White, N J; Farrar, J J

    1999-09-01

    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

  6. Microtensile and tensile bond strength of single-bottle adhesives: a new test method.

    PubMed

    Abdalla, A I

    2004-04-01

    To evaluate the tensile and microtensile bond strength of five single-bottle adhesives to dentine, extracted human molar teeth were used. For each tooth dentine was exposed on the occlusal surface by cutting with an isomet saw and the remaining part was mounted in a plastic ring using dental stone. The tested adhesive materials were: Scotchbond 1, Syntac SC, One-Step, Prime & Bond 2.1 and Clearfil SE Bond. The adhesive was applied to either 1 mm(2) of dentine or a circular area with a diameter of 3.9 mm. Composite resin Clearfil AP-X was placed to the adhesives using a Teflon split mould 3.9 mm in diameter and 2.5 mm in height. Tensile and microtensile bond strengths were measured using a universal testing machine at a crosshead speed of 0.5 mm min(-1). Under tensile mode, the bond strengths were 16.7 +/- 3.5, 15.2 +/- 2.5, 11.5 +/- 3.2, 13.7 +/- 2.6, 20.9 +/- 4.2 MPa for each material. Under microtensile mode, the bond strengths were 52.5 +/- 9.5, 55.3 +/- 8.3, 40.5 +/- 5.2, 37.5 +/- 8.7, 60 +/- 6.21 MPa. Fracture pattern of bonded specimens showed 66% cohesive dentine failure in samples tested for tensile bond strength. For the microtensile test, failures were mainly adhesive at the interface between adhesive and dentine (94%). PMID:15089946

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

    SciTech Connect

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

    2005-08-15

    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 forms were made at the Science and Technology Applications Research (STAR) facility in Idaho Falls, Idaho. The durability of the two FBSR waste forms was assessed via the SPFT test in this study. Both samples were multiphase mineral waste forms, so the SPFT test results provide an overall release rate from the multiple mineral species in each sample and are dependent on the amount of each phase present and the mineralogy of the phases present. SPFT testing was performed at temperatures of 25, 40, 70, and 90 C on LAW 1123, while SBW 1173 was only tested at 70 and 90 C. The 70 and 90 C data were compared to each other and the LAW-1123 results were compared to previous testing performed by the Pacific Northwest National Laboratory (PNNL) on a LAW Envelope C (high organic content) waste simulant. The objectives of this study were to obtain forward dissolution rate data for both STAR FBSR bed products (using SPFT tests). Also, a qualitative comparison of the FBSR bed products to a glass waste form (specifically the low-activity reference material (LRM) glass) was performed. For these comparisons, the relative surface areas of the FBSR and glass products had to be measured. Due to the more porous and irregular surface of FBSR bed products, the surface area of the bed products was determined using the Brunauer, Emmett, and Teller (BET) measurement method. The surface area of a glass is much smoother and the calculated geometric surface area is typically used for determining dissolution behavior. Presently there are no specifications or standard release rates that the FBSR tested materials have to meet, e.g. the data from the FBSR testing is normally used during subsequent Performance Assessment (PA) calculations. Since a PA calculation is not part of this study, the LAW and SBW steam reforming samples were compared to each other, to previous LAW FBSR SPFT results, and to the results from the LRM reference glass. The experimental durability data generated from this study suggests that an FBSR mineral waste form product would be an adequate alternative form to borosilicate glass. The tested FBSR mineral waste forms showed normalized release rates for matrix elements such as Si to be more than 200X slower than the LRM glass. However, further durability testing and mineral phase information is recommended to further substantiate these findings.

  8. Prototype Test Results for the Single Photon Detection SLR2000 Satellite Laser Ranging System

    NASA Technical Reports Server (NTRS)

    Zagwodzki, Thomas W.; McGarry, Jan F.; Degnan, John J.; Cheek, Jack W.; Dunn, Peter J.; Patterson, Don; Donovan, Howard

    2004-01-01

    NASA's aging Satellite Laser Ranging (SLR) network is scheduled to be replaced over the next few years with a fully automated single photon detection system. A prototype of this new system, called SLR2000, is currently undergoing field trials at the Goddard Space Flight Center in Greenbelt, Maryland to evaluate photon counting techniques and determine system hardware, software, and control algorithm performance levels and limitations. Newly developed diode pumped microchip lasers and quadrant microchannel plate-based photomultiplier tubes have enabled the development of this high repetition rate single photon detection SLR system. The SLR2000 receiver threshold is set at the single photoelectron (pe) level but tracks satellites with an average signal level typically much less than 1 pe. The 2 kHz laser fire rate aids in satellite acquisition and tracking and will enable closed loop tracking by accumulating single photon count statistics in a quadrant detector and using this information to correct for pointing errors. Laser transmitter beamwidths of 10 arcseconds (FWHM) or less are currently being used to maintain an adequate signal level for tracking while the receiver field of view (FOV) has been opened to 40 arcseconds to accommodate point ahead/look behind angular offsets. In the near future, the laser transmitter point ahead will be controlled by a pair of Risley prisms. This will allow the telescope to point behind and enable closure of the receiver FOV to roughly match the transmitter beam divergence. Bandpass filters (BPF) are removed for night tracking operations while 0.2 nm or 1 nm filters are used during daylight operation. Both day and night laser tracking of Low Earth Orbit (LEO) satellites has been achieved with a laser transmitter energy of only 65 microjoules per pulse. Satellite tracking is presently limited to LEO satellites until the brassboard laser transmitter can be upgraded or replaced. Simultaneous tracks have also been observed with NASA s SLR standard, MOBLAS 7, for the purposes of data comparison and identification of biases. Work continues to optimize the receive optics; upgrade or replace the laser transmitter; calibrate the quadrant detector, the point ahead Risley prisms, and event timer verniers; and test normal point generation with SLR2000 data. This paper will report on the satellite tracking results to date, issues yet to be resolved, and future plans for the SLR2000 system.

  9. Neuromuscular Evaluation With Single-Leg Squat Test at 6 Months After Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Hall, Michael P.; Paik, Ronald S.; Ware, Anthony J.; Mohr, Karen J.; Limpisvasti, Orr

    2015-01-01

    Background: Criteria for return to unrestricted activity after anterior cruciate ligament (ACL) reconstruction varies, with some using time after surgery as the sole criterion—most often at 6 months. Patients may have residual neuromuscular deficits, which may increase the risk of ACL injury. A single-leg squat test (SLST) can dynamically assess for many of these deficits prior to return to unrestricted activity. Hypothesis: A significant number of patients will continue to exhibit neuromuscular deficits with SLST at 6 months after ACL reconstruction. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Patients using a standardized accelerated rehabilitation protocol at their 6-month follow-up after primary ACL reconstruction were enrolled. Evaluation included bilateral SLST, single-leg hop distance, hip abduction strength, and the subjective International Knee Documentation Committee (IKDC) score. Results: Thirty-three patients were enrolled. Poor performance of the operative leg SLST was found in 15 of 33 patients (45%). Of those 15 patients, 7 (45%) had concomitant poor performance of the nonoperative leg compared with 2 of 18 patients (11%) in those who demonstrated good performance in the operative leg. The poor performers were significantly older (33.6 years) than the good performers (24.2 years) (P = .007). Those with poor performance demonstrated decreased hip abduction strength (17.6 kg operative leg vs 20.5 kg nonoperative leg) (P = .024), decreased single-leg hop distance (83.3 cm operative leg vs 112.3 cm nonoperative leg) (P = .036), and lower IKDC scores (67.9 vs 82.3) (P = .001). Conclusion: Nearly half of patients demonstrated persistent neuromuscular deficits on SLST at 6 months, which is when many patients return to unrestricted activity. Those with poor performance were of a significantly older age, decreased hip abduction strength, decreased single-leg hop distance, and lower IKDC subjective scores. Clinical Relevance: The SLST can be used to identify neuromuscular risk factors for ACL rupture. Many patients at 6 months have persistent neuromuscular deficits on SLST. Caution should be used when using time alone to determine when patients can return to unrestricted activity. PMID:26665033

  10. Scaling submillimeter single-cycle transients toward megavolts per centimeter field strength via optical rectification in the organic crystal OH1.

    PubMed

    Ruchert, Clemens; Vicario, Carlo; Hauri, Christoph P

    2012-03-01

    We present the generation of high-power single-cycle terahertz (THz) pulses in the organic salt crystal 2-[3-(4-hydroxystyryl)-5.5-dimethylcyclohex-2-enylidene]malononitrile or OH1. Broadband THz radiation with a central frequency of 1.5 THz (λ(c)=200 μm) and high electric field strength of 440 kV/cm is produced by optical rectification driven by the signal of a powerful femtosecond optical parametric amplifier. A 1.5% pump to THz energy conversion efficiency is reported, and pulse energy stability better than 1% RMS is achieved. An approach toward the realization of higher field strength is discussed. PMID:22378431

  11. Single stars in the Hyades open cluster. Fiducial sequence for testing stellar and atmospheric models

    NASA Astrophysics Data System (ADS)

    Kopytova, Taisiya G.; Brandner, Wolfgang; Tognelli, Emanuele; Prada Moroni, Pier Giorgio; Da Rio, Nicola; Röser, Siegfried; Schilbach, Elena

    2016-01-01

    Context. Age and mass determinations for isolated stellar objects remain model-dependent. While stellar interior and atmospheric theoretical models are rapidly evolving, we need a powerful tool to test them. Open clusters are good candidates for this role. Aims: We aim to create a fiducial sequence of stellar objects for testing stellar and atmospheric models. Methods: We complement previous studies on the Hyades multiplicity by Lucky Imaging observations with the AstraLux Norte camera. This allows us to exclude possible binary and multiple systems with companions outside a 2-7 AU separation and to create a single-star sequence for the Hyades. The sequence encompasses 250 main-sequence stars ranging from A5V to M6V. Using the Tool for Astrophysical Data Analysis (TA-DA), we create various theoretical isochrones applying different combinations of interior and atmospheric models. We compare the isochrones with the observed Hyades single-star sequence on J vs. J-Ks, J vs. J-H, and Ks vs. H-Ks color-magnitude diagrams. As a reference we also compute absolute fluxes and magnitudes for all stars from X-ray to mid-infrared based on photometric measurements available in the literature(ROSAT X-ray, GALEX UV, APASS gri, 2MASS JHKs, and WISE W1 to W4). Results: We find that combinations of both PISA and DARTMOUTH stellar interior models with BT-Settl 2010 atmospheric models describe the observed sequence well. We use PISA in combination with BT-Settl 2010 models to derive theoretical predictions for physical parameters (Teff, mass, log g) of 250 single stars in the Hyades. The full sequence covers the mass range of 0.13-2.30 M⊙, and effective temperatures between 3060 K and 8200 K. Conclusions: Within the measurement uncertainties, the current generation of models agree well with the single-star sequence. The primary limitations are the uncertainties in the measurement of the distances to individual Hyades members, and uncertainties in the photometry. Gaia parallaxes, photometry, and spectroscopy will greatly reduce the uncertainties in particular at the lowest mass range, and will enable us to test model predictions with greater confidence. Additionally, a small (~0.05 mag) systematic offset can be noted in J vs. J-K and K vs. H-K diagrams - the observed sequence is shifted to redder colors than the theoretical predictions. Based on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by the Max-Planck Institut für Astronomie and the Instituto de Astrofísica de Andalucía (CSIC).Full Table 2 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/585/A7

  12. Sexual dimorphic features within extant great ape faciodental skeletal anatomy and testing the single species hypothesis.

    PubMed

    Cameron, D W

    1997-01-01

    This paper examines sexually dimorphic skeletal characters within the face and upper dentition of extant hominids (great ape), not including members of the Hominini. Specimens of Pan paniscus, Pan troglodytes, Gorilla gorilla, and Pongo pygmaeus are used to help identify likely sex specific characters for the Hominidae. The aim of this paper is to identify extant hominid faciodental sexual features which can be used to help sex fossil specimens. A morphometric and skeletal study of sexual variability demonstrates relatively diverse patterns of sexual variability within the extant hominids. In terms of morphometrics, P. paniscus is relatively non-dimorphic, while P. troglodytes, Gorilla and Pongo display a large degree of sexual dimorphism. In their respective skeletal anatomies, however, each has specific characters which tend to differentiate between the sexes. Some faciodental sex features are shown to be common amongst all four taxa and as such are likely to be important criteria for determining the sex of Miocene and Plio-Pleistocene fossil hominid specimens. The construction of extant great ape sexual ranges of variability are also important in helping to test the fossil ape single species hypotheses. The testing of sex and species ranges of variability should employ range based statistics not only because they are sample size independent, (relative to C.V.) but also because they are of low power. PMID:9428188

  13. Single Event Effects Test Results for Advanced Field Programmable Gate Arrays

    NASA Technical Reports Server (NTRS)

    Allen, Gregory R.; Swift, Gary M.

    2006-01-01

    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.

  14. Gain-Matching and Efficiency Tests On Double- and Single-Ended Hodoscope Arrays

    NASA Astrophysics Data System (ADS)

    Miller, Andrew; SeaQuest Collaboration

    2011-10-01

    E-906/SeaQuest is a fixed target experiment analyzing the ratio of anti-down to anti-up quarks in the nucleon sea of the proton as well as studying shadowing, anti-shadowing, and energy loss effects using the Drell-Yan process. The muon detector consists of a two-magnet spectrometer and 4 stations of drift chamber and hodoscope combinations. The hodoscopes are used to produce the fast trigger system for the spectrometer. In order to prepare the station 3 and 4 hodoscope arrays for the experiment, the PMTs were initially gain-matched by using a multichannel analyzer to record the spectra from a Cs137 radiation source and adjusting the voltage so the Compton edge occurred in the same channel. Once this was completed, cosmic ray rate tests were performed using various discriminator thresholds values to verify the chosen PMT voltages. This is critical as each 16-channel discriminator to be used must have a single threshold. Interesting effects observed in these rates due to nearby shielding will also be shown to illustrate the special difficulties in using cosmic ray muons for these tests. This work was supported in part by U.S. Department of Energy, Office of Nuclear Physics, under contract No. DE-AC02-06CH11357.

  15. Workshop on Radio Transients

    NASA Astrophysics Data System (ADS)

    Croft, Steve; Gaensler, Bryan

    2012-04-01

    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.

  16. Design and Experimental Test Plan for Hybrid Sulfur Single Cell Pressurized Electrolyzer

    SciTech Connect

    Steeper, T. J.; Steimke, J. L.

    2005-09-01

    The Hybrid Sulfur (HyS) process is one of the leading thermochemical cycles being studied as part of the DOE Nuclear Hydrogen Initiative (NHI). SRNL is conducting analyses and research and development for the Department of Energy on the HyS process. A conceptual design report and development plan for the HyS process was issued on April 1, 2005 [Buckner, et. al., 2005] , and a report on atmospheric testing of a sulfur dioxide depolarized electrolyzer (SDE), a major component of the HyS process, was issued on August 1, 2005 [Steimke, 2005]. The purpose of this report is to document work related to the design and experimental test plan for a pressurized SDE. Pressurized operation of the SDE is a key requirement for development of an efficient and cost-effective HyS process. The HyS process, a hybrid thermochemical cycle proposed and investigated in the 1970s and early 1980s by Westinghouse Electric Corporation, is a high priority candidate for NHI due to the potential for high efficiency and its relatively high level of technical maturity. It was demonstrated in laboratory experiments by Westinghouse in 1978. Process improvements and component advancements that build on that work are being pursued. One of the objectives of the current work is to develop the SDE in order to permit the demonstration of a closed-loop laboratory model of the HyS process. The heart of the HyS process for generating hydrogen is a bank of electrolyzers incorporating sulfur dioxide depolarized anodes. SRNL planned, designed, built and operated a facility for testing single cell electrolyzers at ambient temperature and near atmospheric pressure during the spring and summer of 2005. The major contribution of the SRNL work was the establishment of the proof-of-concept for utilizing the proton-exchange-membrane (PEM) cell design for the SDE operation. Since PEM cells are being extensively developed for automotive fuel cell use, they offer significant potential for cost-effective application for the HyS Process. This report discusses the modifications necessary to the existing SRNL sulfur dioxide depolarized electrolyzer test facility to allow testing at up to 80 C and 90 psig. Because of the need for significant additional equipment and the ability to infer performance results to higher pressures, it recommends delaying further modifications to support testing at up to 300 psig (the commercial goal) until other, higher priority technical issues are addressed. These issues include membrane material selection, component designs, catalyst type and loading, etc. The factors and rationale that should be considered in developing and executing a detailed test matrix for pressurized operation are also discussed. In addition, an electrolyzer assembly design has been developed to allow the testing of different Membrane Electrode Assemblies (MEA's) as part of the planned FY06 HyS Development Program to complete selection of component design specifications for the HyS electrolyzer. MEA's are used in PEM cells to allow intimate contact and minimal resistance between the electrodes and the electrolyte layer. The pressurized electrolyzer assembly presented in this report will facilitate rapid change-out and testing of various MEA designs as part of the electrolyzer development effort.

  17. Transient dynamics and the destabilizing effects of prey heterogeneity.

    PubMed

    Steiner, Christopher F; Klausmeier, Christopher A; Litchman, Elena

    2012-03-01

    The presence of prey heterogeneity and weakly interacting prey species is frequently viewed as a stabilizer of predator-prey dynamics, countering the destabilizing effects of enrichment and reducing the amplitude of population cycles. However, prior model explorations have largely focused on long-term, dynamic attractors rather than transient dynamics. Recent theoretical work shows that the presence of prey that are defended from predation can have strongly divergent effects on dynamics depending on time scale: prey heterogeneity can counteract the destabilizing effects of enrichment on predator-prey dynamics at long time scales but strongly destabilize systems during transient phases by creating long periods of low predator/prey abundance and increasing extinction probability (an effect that is amplified with increasing enrichment). We tested these general predictions using a planktonic system composed of a zooplankton predator and multiple algal prey. We first parameterized a model of our system to generate predictions and tested these experimentally. Our results qualitatively supported several model predictions. During transient phases, presence of defended algal prey increased predator extinctions at low and high enrichment levels compared to systems with only a single edible prey. This destabilizing effect was moderated at higher dilution rates, as predicted by our model. When examining dynamics beyond initial oscillations, presence of the defended prey increased predator-prey temporal variability at high nutrient enrichment but had no effect at low nutrient levels. Our results highlight the importance of considering transient dynamics when assessing the role of stabilizing factors on the dynamics of food webs. PMID:22624217

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

    NASA Astrophysics Data System (ADS)

    Velický, B.; Kalvová, A.; Špička, V.

    2010-01-01

    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.

  19. CHARACTERIZATION TESTING AND ANALYSIS OF SINGLE CELL SO2 DEPOLARIZED ELECTROLYZER

    SciTech Connect

    Steimke, J; Timothy Steeper, T

    2006-09-15

    This document reports work performed at the Savannah River National Laboratory (SRNL) that further develops the use of a proton exchange membrane or PEM-type electrochemical cell to produce hydrogen via SO{sub 2}-depolarized water electrolysis. This work was begun at SRNL in 2005. This research is valuable in achieving the ultimate goal of an economical hydrogen production process based on the Hybrid Sulfur (HyS) Cycle. The HyS Process is a hybrid thermochemical cycle that may be used in conjunction with advanced nuclear reactors or centralized solar receivers to produce hydrogen by water-splitting. Like all other sulfur-based cycles, HyS utilizes the high temperature thermal decomposition of sulfuric acid to produce oxygen. The unique aspect of HyS is the generation of hydrogen in a water electrolyzer that is operated under conditions where dissolved sulfur dioxide depolarizes the anodic reaction, resulting in substantial voltage reduction. Sulfur dioxide is oxidized at the anode, producing sulfuric acid that is sent to the acid decomposition portion of the cycle. The focus of this work was to conduct single cell electrolyzer tests in order to prove the concept of SO{sub 2}-depolarization and to determine how the results can be used to evaluate the performance of key components of the HyS Process. A test facility for conducting SO{sub 2}-depolarized electrolyzer (SDE) testing was designed, constructed and commissioned. The maximum cell current is 50 amperes, which is equivalent to a hydrogen production rate of approximately 20 liters per hour. Feed to the anode of the electrolyzer is sulfuric acid solutions containing dissolved sulfur dioxide. The partial pressure of sulfur dioxide may be varied in the range of 1 to 6 atm (15 to 90 psia). Temperatures may be controlled in the range from ambient to 80 C. Hydrogen generated at the cathode of the cell is collected for the purpose of flow measurement and composition analysis. The test facility proved to be easy to operate, versatile, and reliable.

  20. Transient drainage summary report

    SciTech Connect

    1996-09-01

    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.

  1. Validation of the Bayesian Alcoholism Test Compared to Single Biomarkers in Detecting Harmful Drinking

    PubMed Central

    Korzec, Sanne; Korzec, Alex; Conigrave, Katherine; Gisolf, Janneke; Tabakoff, Boris

    2009-01-01

    Aims: Conventional tests for alcohol dependence often fail to detect hazardous and harmful alcohol use (HHAU) accurately. We previously validated the Bayesian Alcoholism Test (BAT) for the detection of HHAU among males. This uses 15 biochemical and clinical variables, including questionnaire data to calculate the probability of harmful (>80 g alcohol/day), hazardous (40–80 g/day) and ‘moderate’ (<40 g/day) drinking. Here we investigate the BAT's diagnostic performance when more limited clinical data are available. Methods: The WHO/ISBRA Collaborative Project recruited subjects from the general community and alcohol dependence treatment services. We analysed data from male drinkers: 318 alcohol dependent, 220 heavy and 712 moderate drinkers. Drinking was assessed using the Alcohol-Use Disorders and Associated Disabilities Interview Schedule. Eight of 15 markers used in the original BAT could be extracted from the WHO/ISBRA dataset. Results: Comparing harmful to moderate drinkers, the area under the ROC curve for BAT (0.90) was significantly higher than that for CDT (0.82), GGT (0.77) and AST (0.76). Comparing hazardous to moderate drinkers, the area under the ROC curve for BAT (0.78) was significantly higher than that for AST (0.65) but not significantly higher than that for CDT (0.71) and GGT (0.70). For all 1250 subjects, the amount consumed correlated significantly better with BAT (0.65) than with CDT (0.52), GGT (0.44) or AST (0.40) alone. Conclusions: The BAT is more accurate than commonly used single biological markers in detecting harmful alcohol use, even when only half the input requirements are available. Computerized record keeping increases the practicality of use of algorithms in the detection of harmful drinking. PMID:19293144

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

    SciTech Connect

    Chattopadhyay, S.; Kim, C.; Massoletti, D.; Zholents, A.

    1997-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

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

    1979-01-01

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2010-02-01

    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 Poincar 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).

  5. COAXIAL HOM COUPLER DESIGNS TESTED ON A SINGLE CELL NIOBIUM CAVITY

    SciTech Connect

    Peter Kneisel; Gianluigi Ciovati; Genfa Wu; Jacek Sekutowicz

    2006-08-21

    Poster - 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 feed through 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 feed through incorporating a sapphire rf window. 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.

  6. Coaxial HOM Coupler designs tested on a single cell niobium cavity

    SciTech Connect

    Peter Kneisel; Genfa Wu; Gianluigi Ciovati; Jacek Sekutowicz

    2006-08-28

    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.

  7. Transient effects in turbulence modelling

    SciTech Connect

    Boyle, D.R.; Golay, M.W.

    1980-06-01

    Measurements of turbulence field data are reported for recirculating water flows under steady-state and transient flow conditions in an improved 1/15 scale FFTF outlet plenum test-cell. A dual-channel Laser Doppler Anemometer is used, and a unique method for performing transient measurements is developed and analyzed. The experimental behavior is predicted with a modified version of the VARR-II fluid dynamics code, and the suitability of using the steady-state turbulence model closure assumptions for analysis of transient flows is evaluated. A relationship between K-sigma and K-epsilon turbulence models is derived, and the two models are found to be nearly equivalent.

  8. Comparison between single and combined post-treatment with S-Methyl-N,N-diethylthiolcarbamate sulfoxide and taurine following transient focal cerebral ischemia in rat brain.

    PubMed

    Gharibani, P; Modi, J; Menzie, J; Alexandrescu, A; Ma, Z; Tao, R; Prentice, H; Wu, J-Y

    2015-08-01

    We have recently reported on the efficacy of an N-methyl-d-aspartate (NMDA) receptor partial antagonist, S-Methyl-N,N-diethylthiolcarbamate sulfoxide (DETC-MeSO), in improving outcome following stroke, including reduced infarct size and calcium influx, suppressing the endoplasmic reticulum (ER) stress-induced apoptosis as well as improving behavioral outcome. DETC-MeSO was shown to suppress the protein kinase R-like endoplasmic reticulum kinase (PERK) pathway, one of the major ER stress pathways. Several studies including ours have provided evidence that taurine also has neuroprotective effects through reducing apoptosis and inhibiting activating transcription factor 6 (ATF6) and inositol requiring enzyme 1 (IRE-1) pathways. We hypothesized that a combined treatment with DETC-MeSO and taurine would ameliorate ischemia-induced brain injury by inhibiting all three ER stress pathways. Twenty four hours following reperfusion of a 2-h ischemic stroke, rats received either 0.56-mg/kg DETC-MeSO or 40-mg/kg of taurine, either alone or in combination, subcutaneously for 4days. Our study showed that combined DETC-MeSO and taurine, but not DETC-MeSO alone at the dose used, greatly reduced the infarct size, improved performance on the neuro-score test and attenuated proteolysis of αII-spectrin. Meanwhile, the level of the pro-apoptotic protein, Bax, declined and the anti-apoptotic protein, B-cell lymphoma 2 (BCL-2), expression was markedly increased. Combination therapy decreased both caspase-12 and caspase-3 activation by preventing the release of Cytochrome-c from mitochondria, indicating attenuation of apoptosis in ischemic infarct. Glucose-regulated protein (GRP)78 as a marker of the unfolded protein response decreased and levels of the key ER stress protein markers p-PERK-ATF4, p-eIF2α and cleaved-ATF-6 were found to significantly decline. NeuN expression levels indicated that more neurons were protected in the presence of DETC-MeSO and taurine. We also showed that combined treatment can prevent gliosis and increase p-AKT a pro-survival marker in the penumbra. Therefore, we conclude that combined treatment with both DETC-MeSO and taurine synergistically inhibits all three ER stress pathways and apoptosis and therefore can be a novel and effective treatment after ischemic stroke. PMID:26022360

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

    SciTech Connect

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

    1999-03-04

    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.

  10. SEU and Test Considerations for FPGA Devices

    NASA Technical Reports Server (NTRS)

    Berg, Malanie

    2006-01-01

    This viewgraph presentation provides an overview of Field Programmable Gate Arrays (FPGAs), what they are, implementations in space missions, and current available technologies. Single Event Upsets (SEUs) and Single Event Transients (SETs) are discussed in relation to their effects on FPGAs. Testing goals, considerations, and data analysis are reviewed.

  11. The Zwicky Transient Facility

    NASA Astrophysics Data System (ADS)

    Kulkarni, Shrinivas R.

    2016-01-01

    The Zwicky Transient Facility (ZTF) has been designed with a singular focus: a systematic exploration of the night sky at a magnitude level well suited for spectral classification and follow up with the existing class of 4-m to 10-m class telescopes. ZTF is the successor to the Palomar Transient Factory (PTF). The discovery engine for ZTF is a 47 square degree camera (realized through 16 e2V monolithic CCDs) that fills the entire focal plane of the 48-inch Oschin telescope of the Palomar Observatory. Single 30-s epoch sensitivity is about 20.5 in g and R bands. The Infarared Processing & Analysis Center (IPAC) is the data center for ZTF. ZTF is a public-private partnership with equal contributions from a consortium of world-wide partners and an NSF MSIP grant. Forty percent of ZTF time is set aside for two major community surveys: a 3-day cadence survey of high latitudes (to mimic LSST) and a time domain survey of the entire Northern Galactic plane. We expect first light in February 2017 and begin a 3-year survey starting summer of 2017. The first year will be spent on building up deep reference images of the sky (a must for transient surveys). During the second year IPAC will deliver near archival quality photometric products within 12 hours of observations. By comparison to reference images photometric alerts will be sent out. Year 3 will see the near real-time release of image differencing products. A Community Science Advisory Committee (CSAC), chaired by S. Ridgway (NOAO), has been set up to both advise the PI and to ensure that the US community's interests are well served. Astronomers interested in getting a head start on ZTF may wish to peruse the data releases from PTF. Young people (or young at heart) may wish to attend the annual summer school on PTF/ZTF (August, Caltech campus). The Principal Investigator (PI) for the project is S. Kulkarni and the Project Scientist is Eric Bellm.For further details please consult http://www.ptf.caltech.edu/ztf

  12. 100-liter transient transfection.

    PubMed

    Girard, Philippe; Derouazi, Madiha; Baumgartner, Gwendoline; Bourgeois, Michaela; Jordan, Martin; Jacko, Barbara; Wurm, Florian M

    2002-01-01

    This is the first report of two successful 100 l scale transienttransfections in a standard stirred bioreactor. More than half a gram of a monoclonal antibody (IgG) were produced in less than 10 days using a technology called large-scale transient gene expression(LS-TGE). Suspension adapted HEK 293 EBNA SF cells were transfectedwithin a 150 l (nominal) bioreactor by a modified calcium phosphateco-precipitation method with more than 75 mg of plasmid DNA per run.A mixture of three different plasmids, one encoding for the heavychain of a human recombinant immunoglobulin, the other for the corresponding light chain and a third one for the green fluorescent protein (GFP, 2-4% of DNA in transfection cocktail)were co-transfected. The GFP vector was chosen to monitor transfection efficiency. Expression of GFP could be registered asearly as 20 h after DNA addition, using fluorescence microscopy. We demonstrate that transient transfection can be done at the100 l scale, thus providing a new tool to produce hundreds of milligrams or even gram amounts of recombinant protein. Akey advantage of LS-TGE resides in its speed. In the presentedcases, the entire production process for the synthesis of halfa gram of a recombinant antibody, including DNA preparationand necessary expansion of cells prior to transfection, wasexecuted in less than a month. Having an established transfection/expression process allows to run productioncampaigns for any given protein, within one facility, with onesingle host cell line and therefore only one single seed train. Without any need to create and maintain stable cell lines, expression of new r-proteins is not only faster and more economical but also more flexible. PMID:19003082

  13. Perturbations for transient acceleration

    SciTech Connect

    Vargas, Cristofher Zuiga; Zimdahl, Winfried; Hiplito-Ricaldi, Wiliam S. E-mail: hipolito@ceunes.ufes.br

    2012-04-01

    According to the standard ?CDM model, the accelerated expansion of the Universe will go on forever. Motivated by recent observational results, we explore the possibility of a finite phase of acceleration which asymptotically approaches another period of decelerated expansion. Extending an earlier study on a corresponding homogeneous and isotropic dynamics, in which interactions between dark matter and dark energy are crucial, the present paper also investigates the dynamics of the matter perturbations both on the Newtonian and General Relativistic (GR) levels and quantifies the potential relevance of perturbations of the dark-energy component. In the background, the model is tested against the Supernova type Ia (SNIa) data of the Constitution set and on the perturbative level against growth rate data, among them those of the WiggleZ survey, and the data of the 2dFGRS project. Our results indicate that a transient phase of accelerated expansion is not excluded by current observations.

  14. Fracture trace map and single-well aquifer test results in a carbonate aquifer in Berkeley County, West Virginia

    USGS Publications Warehouse

    McCoy, Kurt J.; Podwysocki, Melvin H.; Crider, E. Allen; Weary, David J.

    2005-01-01

    These data contain information on the results of single-well aquifer tests, lineament analysis, and a bedrock geologic map compilation for the low-lying carbonate and shale areas of eastern Berkeley County, West Virginia. Efforts have been initiated by management agencies of Berkeley County in cooperation with the U.S. Geological Survey to further the understanding of the spatial distribution of fractures in the carbonate regions and their correlation with aquifer properties. This report presents transmissivity values from about 200 single-well aquifer tests and a map of fracture-traces determined from aerial photos and field investigations. Transmissivity values were compared to geologic factors possibly affecting its magnitude.

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

    NASA Technical Reports Server (NTRS)

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

    2003-01-01

    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.

  16. Status report of the single heater test chapter 4 integrated analyses

    SciTech Connect

    Lin, W., LLNL

    1998-02-26

    The primary purposes of the Single Heater Test (SHT) are to study the thermal-mechanical responses of the heated block. The SHT is too small and does not have adequate access for a complete study of the coupled thermal-hydrological-chemical processes. The SHT is used as a shake-down/scoping study for the thermal-hydrological- chemical processes. For the thermal-hydrological process, the temporal and spatial variations of the moisture content in the heated block are monitored by neutron logging in Holes 15, 17, 22, and 23, electrical resistivity tomograph (ERT) in Holes 24 to 27. In addition, relative humidity, gas pressure, and temperature are measured in zones between packers in Holes 16 and 18. Temperature is also measured by resistance temperature devices (RTD) in the neutron logging holes (1 5, 17, 22, and 23). Chemical sensors were installed in Holes 20 and 21, but the sensors did not respond to the moisture in the rock. Water was collected from Zone 4 in Hole l6. Calculated temperature distribution and the measured ones are compared. The humidity and gas pressure measurements in Holes 16 and 18 will are discussed. The moisture content measured by neutron logging and ERT will be presented and discussed. Calculated saturation distributions are presented and compared with the neutron logging results and the ERT. The chemical composition of the water collected from Hole 16 is discussed. Fracture closing and opening based on the thermomechanical measurements are summarized. Air permeability changes measured in Holes 16 and 18 are presented. An integrated discussion is presented.

  17. Local strain and damage mapping in single trabeculae during three-point bending tests

    PubMed Central

    Jungmann, R.; Szabo, M.E.; Schitter, G.; Tang, Raymond Yue-Sing; Vashishth, D.; Hansma, P.K.; Thurner, P.J.

    2012-01-01

    The use of bone mineral density as a surrogate to diagnose bone fracture risk in individuals is of limited value. However, there is growing evidence that information on trabecular microarchitecture can improve the assessment of fracture risk. One current strategy is to exploit finite element analysis (FEA) applied to 3D image data of several mm-sized trabecular bone structures obtained from non-invasive imaging modalities for the prediction of apparent mechanical properties. However, there is a lack of FE damage models, based on solid experimental facts, which are needed to validate such approaches and to provide criteria marking elasticplastic deformation transitions as well as microdamage initiation and accumulation. In this communication, we present a strategy that could elegantly lead to future damage models for FEA: direct measurements of local strains involved in microdamage initiation and plastic deformation in single trabeculae. We use digital image correlation to link stress whitening in bone, reported to be correlated to microdamage, to quantitative local strain values. Our results show that the whitening zones, i.e. damage formation, in the presented loading case of a three-point bending test correlate best with areas of elevated tensile strains oriented parallel to the long axis of the samples. The average local strains along this axis were determined to be (1.6 0.9)% at whitening onset and (12 4)% just prior to failure. Overall, our data suggest that damage initiation in trabecular bone is asymmetric in tension and compression, with failure originating and propagating over a large range of tensile strains. PMID:21396601

  18. Intramuscular Single-dose Toxicity Test of Bufonis venonum Pharmacopuncture in Sprague-Dawley Rats

    PubMed Central

    Lee, Kwang-Ho; Sun, Seung-Ho; Yu, Jun-Sang; Kwon, Ki-Rok

    2015-01-01

    Objectives: Bufonis venonum (BV) is the dried white secretions of the auricular and skin glands of the toads Bufo bufo gargarizans or Bufo melanosticus Schneider. This study was performed to evaluate the toxicity of intramuscularly- administered Bufonis venonum pharmacopuncture (BVP) and to calculate its approximate lethality through a single-dose test with Sprague-Dawley (SD) rats. Methods: Twenty male and 20 female 6-week-old SD rats were injected intramuscularly with BVP or normal saline. The animals were divided into four groups with five female and five male rats per group: the control group injected with normal saline at 0.5 mL/animal, the low-dosage group injected with 0.125 mL/animal of BVP, the medium-dosage group injected with 0.25 mL/animal of BVP and the high-dosage group injected with 0.5 mL/animal of BVP. All injections were in the left thighs of the rats. After administration, we conducted clinical observations everyday and body weight measurements on days 3, 7 and 14 after the injection. We also carried out hematology, serum biochemistry, and histological observations on day 15 after treatment. Results: No mortalities were observed in any experimental group. No significant changes in weight, hematology, serum biochemistry, and histological observations that could be attributed to the intramuscular injection of BVP were observed in any experimental group. Conclusion: Lethal dose of BVP administered via intramuscular injection in SD rats is over 0.5 mL/animal. PMID:26998390

  19. Validation of a Pressure-Based Combustion Simulation Tool Using a Single Element Injector Test Problem

    NASA Technical Reports Server (NTRS)

    Thakur, Siddarth; Wright, Jeffrey

    2006-01-01

    The traditional design and analysis practice for advanced propulsion systems, particularly chemical rocket engines, relies heavily on expensive full-scale prototype development and testing. Over the past decade, use of high-fidelity analysis and design tools such as CFD early in the product development cycle has been identified as one way to alleviate testing costs and to develop these devices better, faster and cheaper. Increased emphasis is being placed on developing and applying CFD models to simulate the flow field environments and performance of advanced propulsion systems. This necessitates the development of next generation computational tools which can be used effectively and reliably in a design environment by non-CFD specialists. A computational tool, called Loci-STREAM is being developed for this purpose. It is a pressure-based, Reynolds-averaged Navier-Stokes (RANS) solver for generalized unstructured grids, which is designed to handle all-speed flows (incompressible to hypersonic) and is particularly suitable for solving multi-species flow in fixed-frame combustion devices. Loci-STREAM integrates proven numerical methods for generalized grids and state-of-the-art physical models in a novel rule-based programming framework called Loci which allows: (a) seamless integration of multidisciplinary physics in a unified manner, and (b) automatic handling of massively parallel computing. The objective of the ongoing work is to develop a robust simulation capability for combustion problems in rocket engines. As an initial step towards validating this capability, a model problem is investigated in the present study which involves a gaseous oxygen/gaseous hydrogen (GO2/GH2) shear coaxial single element injector, for which experimental data are available. The sensitivity of the computed solutions to grid density, grid distribution, different turbulence models, and different near-wall treatments is investigated. A refined grid, which is clustered in the vicinity of the solid walls as well as the flame, is used to obtain a steady state solution which may be considered as the best solution attainable with the steady-state RANS methodology. From a design point of view, quick turnaround times are desirable; with this in mind, coarser grids are also employed and the resulting solutions are evaluated with respect to the fine grid solution.

  20. Out-of-School Time Program Test Score Impact for Black Children of Single-Parents

    ERIC Educational Resources Information Center

    Nagle, Barry T.

    2013-01-01

    Out-of-School Time programs and their impact on standardized college entrance exam scores for black or African-American children of single parents who have applied for a competitive college scholarship program is the study focus. Study importance is supported by the large percentage of black children raised by single parents, the large percentage

  1. Criticality of Low-Energy Protons in Single-Event Effects Testing of Highly-Scaled Technologies

    NASA Technical Reports Server (NTRS)

    Pellish, Jonathan A.; Marshall, Paul W.; Rodbell, Kenneth P.; Gordon, Michael S.; LaBel, Kenneth A.; Schwank, James R.; Dodds, Nathaniel A.; Castaneda, Carlos M.; Berg, Melanie D.; Kim, Hak S.; Phan, Anthony M.; Seidleck, Christina M.

    2014-01-01

    We report low-energy proton and low-energy alpha particle single-event effects (SEE) data on a 32 nm silicon-on-insulator (SOI) complementary metal oxide semiconductor (CMOS) latches and static random access memory (SRAM) that demonstrates the criticality of using low-energy protons for SEE testing of highly-scaled technologies. Low-energy protons produced a significantly higher fraction of multi-bit upsets relative to single-bit upsets when compared to similar alpha particle data. This difference highlights the importance of performing hardness assurance testing with protons that include energy distribution components below 2 megaelectron-volt. The importance of low-energy protons to system-level single-event performance is based on the technology under investigation as well as the target radiation environment.

  2. 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...

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

    ERIC Educational Resources Information Center

    Lo, Ya-yu; Konrad, Moira

    2007-01-01

    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

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

    ERIC Educational Resources Information Center

    Kyllingsbaek, Soren; Markussen, Bo; Bundesen, Claus

    2012-01-01

    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

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

    SciTech Connect

    LaBel, K.A.; Gates, M.M.; Moran, A.K.; Seidleck, C.M. [Hughes Marshall, P.; Kinnison, J.; Carkhuff, B.

    1996-12-01

    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.

  6. Brain single photon emission tomography and hypercapnia test in testing cerebrovascular reserve capacity, in Moya moya disease.

    PubMed

    Sirucek, Pavel; Vaclav, Prochazka; Hrbac, Tomas; Kraft, Otto; Chmelova, Jana; Dvorackova, Jana

    2008-01-01

    Moya moya is a progressive cerebral occlusive vasculopathy, rare in European countries. We describe a case of a young woman with right-hand side hemiparesis, mixed expressive aphasia, organic psychosyndrome and cognitive malfunction. Detailed imaging methods displayed bilateral stenosis of the internal carotid artery, bilateral ischemic cerebral changes and bilateral perfusion deficit, which guided us to the final diagnosis. Before the bypass surgery, cerebrovascular reserve capacity (vasoreactivity), by the brain single photon emission tomography and hypercapnia, were assessed and the lower cerebrovascular reserve was demonstrated. Bilateral bypass surgery with extracranial-intracranial anastomosis, improved the neurological deficit. Diagnosis was confirmed by histological examination of the vessel wall specimen. PMID:19081864

  7. Comparison of the results of short-term static tests and single-pass flow-through tests with LRM glass.

    SciTech Connect

    Ebert, W. L.; Chemical Engineering

    2007-01-29

    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.

  8. Transient Voltage Recorder

    NASA Astrophysics Data System (ADS)

    Medelius, Pedro J.; Simpson, Howard J.

    2002-09-01

    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.

  9. Development and Preclinical Testing of a High Affinity Single Chain Antibody against (+)-Methamphetamine

    PubMed Central

    Peterson, Eric C.; Laurenzana, Elizabeth M.; Atchley, William T.; Hendrickson, Howard; Owens, S. Michael

    2009-01-01

    Chronic or excessive (+)-methamphetamine (METH) use often leads to addiction and toxicity to critical organs like the brain. With medical treatment as a goal, a novel single chain variable fragment (scFv) against METH was engineered from anti-METH monoclonal antibody mAb6H4 (IgG, ? light chain, KD = 11 nM) and found to have similar ligand affinity (KD = 10 nM) and specificity as mAb6H4. The anti-METH scFv (scFv6H4) was cloned, expressed in yeast, purified and formulated as a naturally occurring mixture of monomer (~75%) and dimer (~25%). To test the in vivo efficacy of the scFv6H4, male Sprague Dawley rats (n=5) were implanted with 3-day sc osmotic pumps delivering 3.2 mg/kg/day METH. After reaching steady-state METH concentrations, an i.v. dose of scFv6H4 (36.5 mg/kg, equimolar to the METH body burden) was administered along with a [3H]-scFv6H4 tracer. Serum pharmacokinetic (PCKN) analysis of METH and [3H]-scFv6H4 showed that the scFv6H4 caused an immediate 65-fold increase in the METH concentrations and a 12-fold increase in the serum METH area under the concentration-time curve from 0480 min after scFv6H4 administration. The scFv6H4 monomer was quickly cleared or converted to multivalent forms with an apparent t1/2?z of 5.8 min. In contrast, the larger scFv6H4 multivalent forms (dimers, trimers, etc.) showed a much longer t1/2?z (228 min), and the significantly increased METH serum molar concentrations correlated directly with scFv6H4 serum molar concentrations. Considered together these data suggested that the scFv6H4 multimers (and not the monomer) were responsible for the prolonged redistribution of METH into the serum. PMID:18192498

  10. Development and preclinical testing of a high-affinity single-chain antibody against (+)-methamphetamine.

    PubMed

    Peterson, Eric C; Laurenzana, Elizabeth M; Atchley, William T; Hendrickson, Howard P; Owens, S Michael

    2008-04-01

    Chronic or excessive (+)-methamphetamine (METH) use often leads to addiction and toxicity to critical organs like the brain. With medical treatment as a goal, a novel single-chain variable fragment (scFv) against METH was engineered from anti-METH monoclonal antibody mAb6H4 (IgG, kappa light chain, K(d) = 11 nM) and found to have similar ligand affinity (K(d) = 10 nM) and specificity as mAb6H4. The anti-METH scFv (scFv6H4) was cloned, expressed in yeast, purified, and formulated as a naturally occurring mixture of monomer ( approximately 75%) and dimer ( approximately 25%). To test the in vivo efficacy of the scFv6H4, male Sprague-Dawley rats (n = 5) were implanted with 3-day s.c. osmotic pumps delivering 3.2 mg/kg/day METH. After reaching steady-state METH concentrations, an i.v. dose of scFv6H4 (36.5 mg/kg, equimolar to the METH body burden) was administered along with a [(3)H]scFv6H4 tracer. Serum pharmacokinetic analysis of METH and [(3)H]scFv6H4 showed that the scFv6H4 caused an immediate 65-fold increase in the METH concentrations and a 12-fold increase in the serum METH area under the concentration-time curve from 0 to 480 min after scFv6H4 administration. The scFv6H4 monomer was quickly cleared or converted to multivalent forms with an apparent t(1/2lambdaz) of 5.8 min. In contrast, the larger scFv6H4 multivalent forms (dimers, trimers, etc.) showed a much longer t(1/2lambdaz) (228 min), and the significantly increased METH serum molar concentrations correlated directly with scFv6H4 serum molar concentrations. Considered together, these data suggested that the scFv6H4 multimers (and not the monomer) were responsible for the prolonged redistribution of METH into the serum. PMID:18192498

  11. Functional Interrupts and Destructive Failures from Single Event Effect Testing of Point-Of-Load Devices

    NASA Technical Reports Server (NTRS)

    Chen, Dakai; Phan, Anthony; Kim, Hak; Swonger, James; Musil, Paul; LaBel, Kenneth

    2013-01-01

    We show examples of single event functional interrupt and destructive failure in modern POL devices. The increasing complexity and diversity of the design and process introduce hard SEE modes that are triggered by various mechanisms.

  12. Assessment of the sensitivity of the gamma-interferon test and the single intradermal comparative cervical test for the diagnosis of bovine tuberculosis under field conditions.

    PubMed

    Praud, A; Boschiroli, M L; Meyer, L; Garin-Bastuji, B; Dufour, B

    2015-01-01

    In some French départements, the eradication of bovine tuberculosis is incomplete and usual skin tests [single intradermal tuberculin test (SIT) and single intradermal comparative cervical test (SICCT)] have poor specificity due to cross-reactions with non-pathogenic mycobacteria, causing economic losses. In Côte d'Or (Burgundy, France), an experimental serial testing scheme based on the combination of SICCT and gamma-interferon (IFN-γ) tests has been initiated in order to shorten the interval between suspicion and its invalidation in herds with false-positive results to skin tests. Our aim was to assess the scheme's sensitivity and to compare it to the sensitivity of the screening scheme recommended by the European Commission. Our study included 1768 animals from Côte d'Or. The sensitivities of both schemes were estimated using a Bayesian approach. The individual sensitivity of the IFN-γ test [88·1%, 95% credibility interval (CrI) 72·8-97·5] was not significantly different from individual SICCT sensitivity (80·3%, 95% CrI 61·6-98·0) and individual SIT sensitivity (84·2%, 95% CrI 59·0-98·2). The individual specificity of the IFN-γ test was 62·3% (95% CrI 60·2-64·5). No significant difference could be demonstrated between the sensitivities of the serial testing scheme used in Côte d'Or (73·1%, 95% CrI 41·1-100) and the European Union serial testing scheme (70·1%, 95% CrI 31·5-100·0). PMID:24576504

  13. Structurally responsive oligonucleotide-based single-probe lateral-flow test for detection of miRNA-21 mimics.

    PubMed

    Kor, Kamalodin; Turner, Anthony P F; Zarei, Kobra; Atabati, Morteza; Beni, Valerio; Mak, Wing Cheung

    2016-02-01

    A single-probe strip test for the rapid and sensitive detection of miRNA-21 mimics is reported herein. Highly specific structurally responsive bi-functional, thiol and biotin, DNA/LNA oligonucleotide probes (molecular beacons-MB) were designed and conjugated with gold nanoparticles (AuNPs) (i.e. biotin-MB-AuNPs). The proposed design had the ability to modulate the accessibility of the biotin group as a function of the presence of a miRNA target allowing the interaction of the boilable with the streptavidin test zone only in the presence of the miRNA-21 mimics. For quantitative evaluation, images of the strip tests were recorded using a flatbed scanner (Epson Perfection V370 Photo). The colour intensities of the test zones of the strip tests were analysed with the ImageJ software (Scion Corp., USA) and quantified as a function of pixel intensity. The response of the strip test was linear over the range 0.5 to 20nM miRNA-21 (limit of detection of 115pM)and showed good reproducibility (intra and inter CVs below 8%); furthermore, the assay was shown to be highly selective, discriminating other interference miRNAs mimics (e.g. miRNA-221 and miRNA-205). Finally, the proposed strip test was used for detection of miRNA-21 mimics in spiked serum samples, demonstrating its potential for point-of-care clinical applications. Main advantages of the single-probe strip test design are its versatility, simplicity and robustness, which can be easily extended to other miRNA targets by tuning the sequence of the single probe. Furthermore, the use of the structurally responsive single probe is particularly relevant in the case of short-length targets, such as miRNA, whereasa conventional sandwich approach might require a careful control of assay conditions such as hybridization temperature and salt concentration. Graphical Abstract Pictorial representation of the working principle of the proposed structurally responsive oligonucleotide-based single-probe lateral-flow test and example of the test response as a function of increasing concentration of target analyte. PMID:26700447

  14. High-energy transients.

    PubMed

    Gehrels, Neil; Cannizzo, John K

    2013-06-13

    We present an overview of high-energy transients in astrophysics, highlighting important advances over the past 50 years. We begin with early discoveries of ?-ray transients, and then delve into physical details associated with a variety of phenomena. We discuss some of the unexpected transients found by Fermi and Swift, many of which are not easily classifiable or in some way challenge conventional wisdom. These objects are important insofar as they underscore the necessity of future, more detailed studies. PMID:23630376

  15. Flow tests of a single fuel element coolant channel for a compact fast reactor for space power

    NASA Technical Reports Server (NTRS)

    Springborn, R. H.

    1971-01-01

    Water flow tests were conducted on a single-fuel-element cooling channel for a nuclear concept to be used for space power. The tests established a method for measuring coolant flow rate which is applicable to water flow testing of a complete mockup of the reference reactor. The inlet plenum-to-outlet plenum pressure drop, which approximates the overall core pressure drop, was measured and correlated with flow rate. This information can be used for reactor coolant flow and heat transfer calculations. An analytical study of the flow characteristics was also conducted.

  16. Detection of false transients

    NASA Astrophysics Data System (ADS)

    Galleani, Lorenzo; Cohen, Leon; Nelson, Douglas J.

    2005-08-01

    When one calculates a time-frequency distribution of white noise there sometimes appear transients of short duration. Superficially, these transients appear to be real signals but they are not. This comes about by random chance in the noise and also because particular types of distributions do not resolve components well in time. These fictitious signals can be misclassified by detectors and hence it is important to understand their origin and statistical properties. We present experimental studies regarding these false transients, and by simulation we statistically quantify their duration for various distributions. We compare the number and duration of the false transients when different distributions are used.

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

    SciTech Connect

    Schock, Alfred

    1995-08-01

    Paper presented at the 29th IECEC in Monterey, CA in August 1994. The present paper describes the fabrication and testing of full-length prototypcial converters, both unfueled and fueled, and presents parametric results of electrically heated tests.

  18. Discrete element simulations and validation tests investigating solids-conveying processes with pressure buildup in single screw extruders

    NASA Astrophysics Data System (ADS)

    Lessmann, Johann-Sebastian; Schoeppner, Volker

    2016-03-01

    The goal of this contribution is to describe a method of simulating solids-conveying processes in single screw extruders which include a defined back pressure leading to a resulting pressure buildup in the screw channel. To do so, use is made of the Discrete Element Method. Material parameters are presented, as well as details concerning the contact model used and the simulation tool EDEM. Additionally, a test setup is presented which has been used to validate the solids-conveying simulations. Results are shown for both simulations and experimental tests. Comparing the results from simulations and measurements shows acceptable conformity. Such simulations and experimental tests are crucial in order to better understand the buildup of pressure in high-speed single-screw extruders.

  19. A Methodology to Hydraulically Parameterize Deformation Zones and Fracture Networks in Fractured Crystalline Rock Using Fracture Borehole Data and Inflow Data from Single- Hole Tests

    NASA Astrophysics Data System (ADS)

    Follin, S.; Hartley, L.; Rhen, I.; Selroos, J.

    2008-12-01

    Three-dimensional, regional, numerical models of groundwater flow and solute transport in fractured crystalline rock are used for two sites in Sweden that are considered for geological disposal of spent nuclear fuel. The models are used to underpin the conceptual modeling that is based on multi-disciplinary data and include descriptions of the geometry of geological features (deformation zones and fracture networks), transient hydrological and chemical boundary conditions, strong spatial heterogeneity in the hydraulic properties, density driven flow, solute transport including rock matrix diffusion, and mixing of different water types in a palaeo-hydrogeological perspective (last 10,000 years). The general approach applied in the numerical modeling was to first parameterize the deformation zones and fracture networks hydraulically using fracture and inflow data from single-hole tests. Second, a confirmatory step was attempted using essentially the same groundwater flow and solute transport model in terms of grid discretization and parameter settings for matching three types of independent field data: 1) large-scale cross-hole (interference) tests, 2) long- term monitoring of groundwater levels, and 3) hydrochemical composition of fracture water and matrix pore water in deep boreholes. We demonstrate here the adopted modelling approach for the first step, i.e. hydraulic parameterization of deformation zones and fracture networks, using single-hole test data from the site investigations undertaken at one of the sites in Sweden (Forsmark). The adopted modelling approach combines a deterministic representation of the major deformation zones with a stochastic representation of the less fractured bedrock outside these zones using the discrete fracture network (DFN) concept. An exponential model for the depth dependency of the in-plane deformation zone transmissivity was suggested based on the data. Lateral heterogeneity was simulated by adding a log-normal random deviate. A tectonic continuum is envisaged for the DFN concept where the number (intensity) of fractures of different sizes follows a power-law relationship. The methodology used to parameterise the discrete fracture networks starts with a connectivity-sensitivity analysis of different DFN models and ends with flow simulations using the most reliable DFN model deduced in the connectivity analysis. The flow simulations were carried out using three different kinds of correlations between fracture transmissivity and fracture size. For each correlation model, the model parameters were changed in a forward manner until a reasonable match against measured specific capacities (Q/?p) was achieved.

  20. Single Group, Pre- and Post-Test Research Designs: Some Methodological Concerns

    ERIC Educational Resources Information Center

    Marsden, Emma; Torgerson, Carole J.

    2012-01-01

    This article provides two illustrations of some of the factors that can influence findings from pre- and post-test research designs in evaluation studies, including regression to the mean (RTM), maturation, history and test effects. The first illustration involves a re-analysis of data from a study by Marsden (2004), in which pre-test scores are