Sample records for engine starting restarting

  1. 40 CFR 86.1236-85 - Engine starting and restarting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Engine starting and restarting. 86... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED...-Fueled and Methanol-Fueled Heavy-Duty Vehicles § 86.1236-85 Engine starting and restarting. (a) Starting...

  2. 40 CFR 1066.425 - Engine starting and restarting.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Engine starting and restarting. 1066... POLLUTION CONTROLS VEHICLE-TESTING PROCEDURES Vehicle Preparation and Running a Test § 1066.425 Engine starting and restarting. (a) Start the vehicle's engine as follows: (1) At the beginning of the test cycle...

  3. 40 CFR 86.1236-85 - Engine starting and restarting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 19 2011-07-01 2011-07-01 false Engine starting and restarting. 86... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED...-Fueled and Methanol-Fueled Heavy-Duty Vehicles § 86.1236-85 Engine starting and restarting. (a) Starting...

  4. 40 CFR 86.1236-85 - Engine starting and restarting.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 20 2013-07-01 2013-07-01 false Engine starting and restarting. 86... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED...-Fueled and Methanol-Fueled Heavy-Duty Vehicles § 86.1236-85 Engine starting and restarting. (a) Starting...

  5. 40 CFR 86.1236-85 - Engine starting and restarting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 20 2012-07-01 2012-07-01 false Engine starting and restarting. 86... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED...-Fueled and Methanol-Fueled Heavy-Duty Vehicles § 86.1236-85 Engine starting and restarting. (a) Starting...

  6. 40 CFR 1066.425 - Engine starting and restarting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Engine starting and restarting. 1066... POLLUTION CONTROLS VEHICLE-TESTING PROCEDURES Vehicle Preparation and Running a Test § 1066.425 Engine starting and restarting. (a) Start the vehicle's engine as follows: (1) At the beginning of the test cycle...

  7. 40 CFR 86.136-90 - Engine starting and restarting.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Engine starting and restarting. 86.136... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... Complete Heavy-Duty Vehicles; Test Procedures § 86.136-90 Engine starting and restarting. (a) Otto-cycle...

  8. 40 CFR 86.136-90 - Engine starting and restarting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Engine starting and restarting. 86.136... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... Complete Heavy-Duty Vehicles; Test Procedures § 86.136-90 Engine starting and restarting. (a) Otto-cycle...

  9. 40 CFR 86.136-90 - Engine starting and restarting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Engine starting and restarting. 86.136... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... Complete Heavy-Duty Vehicles; Test Procedures § 86.136-90 Engine starting and restarting. (a) Otto-cycle...

  10. 40 CFR 86.136-90 - Engine starting and restarting.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Engine starting and restarting. 86.136... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... Complete Heavy-Duty Vehicles; Test Procedures § 86.136-90 Engine starting and restarting. (a) Otto-cycle...

  11. 40 CFR 86.536-78 - Engine starting and restarting.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Engine starting and restarting. 86.536... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for 1978 and Later New Motorcycles; Test Procedures § 86.536-78 Engine starting and restarting. (a...

  12. 40 CFR 86.536-78 - Engine starting and restarting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Engine starting and restarting. 86.536... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for 1978 and Later New Motorcycles; Test Procedures § 86.536-78 Engine starting and restarting. (a...

  13. 40 CFR 86.536-78 - Engine starting and restarting.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Engine starting and restarting. 86.536... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for 1978 and Later New Motorcycles; Test Procedures § 86.536-78 Engine starting and restarting. (a...

  14. 40 CFR 86.536-78 - Engine starting and restarting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Engine starting and restarting. 86.536... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for 1978 and Later New Motorcycles; Test Procedures § 86.536-78 Engine starting and restarting. (a...

  15. 40 CFR 86.1336-84 - Engine starting, restarting, and shutdown.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... (4) If a failure to start occurs during the hot start portion of the test and is caused by engine... stalling. (1) If the engine stalls during the initial idle period of either the cold or hot start test, the engine shall be restarted immediately using the appropriate cold or hot starting procedure and the test...

  16. 40 CFR 86.1336-84 - Engine starting, restarting, and shutdown.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... (4) If a failure to start occurs during the hot start portion of the test and is caused by engine... stalling. (1) If the engine stalls during the initial idle period of either the cold or hot start test, the engine shall be restarted immediately using the appropriate cold or hot starting procedure and the test...

  17. 40 CFR 86.1336-84 - Engine starting, restarting, and shutdown.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... (4) If a failure to start occurs during the hot start portion of the test and is caused by engine... stalling. (1) If the engine stalls during the initial idle period of either the cold or hot start test, the engine shall be restarted immediately using the appropriate cold or hot starting procedure and the test...

  18. 40 CFR 86.236-94 - Engine starting and restarting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Engine starting and restarting. 86.236... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.236-94 Engine starting and...

  19. 40 CFR 86.236-94 - Engine starting and restarting.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Engine starting and restarting. 86.236... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.236-94 Engine starting and...

  20. 40 CFR 86.236-94 - Engine starting and restarting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Engine starting and restarting. 86.236... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.236-94 Engine starting and...

  1. 40 CFR 86.236-94 - Engine starting and restarting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Engine starting and restarting. 86.236... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... New Medium-Duty Passenger Vehicles; Cold Temperature Test Procedures § 86.236-94 Engine starting and...

  2. 40 CFR 1065.930 - Engine starting, restarting, and shutdown.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... cranking time as normal. (c) Respond to engine stalling with the following steps: (1) If the engine stalls... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Engine starting, restarting, and...) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Field Testing and Portable Emission Measurement...

  3. 40 CFR 86.536-78 - Engine starting and restarting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... initial 20 second idle period shall begin when the engine starts. (2) Choke operation. (i) Vehicles... transmission shall be placed in gear 15 seconds after the engine is started. If necessary, braking may be...

  4. Stop/Start: Overview

    Science.gov Websites

    /Start technology conserves energy by shutting off the gasoline engine when the vehicle is at rest, such as at a traffic light, and automatically re-starting it when the driver pushes the gas pedal to go engine when pulling out from a stop and generating electricity which is stored in the battery. Main stage

  5. 40 CFR 86.1336-84 - Engine starting, restarting, and shutdown.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... dynamometer shall be equal (nominal ±0.5 seconds) to the time required with a starter motor. Motoring by the dynamometer shall be terminated not more than one second after the engine starts. The 24 ±1-second free idle... after 15 seconds of cranking, cranking shall cease and the reason for failure to start shall be...

  6. 40 CFR 86.136-90 - Engine starting and restarting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... started. If necessary, braking may be employed to keep the drive wheels from turning. (c) If the vehicle... petroleum-fueled diesel vehicles and the particulate sampling system when testing methanol-fueled diesel... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission...

  7. 40 CFR 1065.525 - Engine starting, restarting, shutdown, and optional repeating of void discrete modes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., and optional repeating of void discrete modes. 1065.525 Section 1065.525 Protection of Environment... repeating of void discrete modes. (a) Start the engine using one of the following methods: (1) Start the... during one of the modes of a discrete-mode test, you may void the results only for that individual mode...

  8. Key Reliability Drivers of Liquid Propulsion Engines and A Reliability Model for Sensitivity Analysis

    NASA Technical Reports Server (NTRS)

    Huang, Zhao-Feng; Fint, Jeffry A.; Kuck, Frederick M.

    2005-01-01

    This paper is to address the in-flight reliability of a liquid propulsion engine system for a launch vehicle. We first establish a comprehensive list of system and sub-system reliability drivers for any liquid propulsion engine system. We then build a reliability model to parametrically analyze the impact of some reliability parameters. We present sensitivity analysis results for a selected subset of the key reliability drivers using the model. Reliability drivers identified include: number of engines for the liquid propulsion stage, single engine total reliability, engine operation duration, engine thrust size, reusability, engine de-rating or up-rating, engine-out design (including engine-out switching reliability, catastrophic fraction, preventable failure fraction, unnecessary shutdown fraction), propellant specific hazards, engine start and cutoff transient hazards, engine combustion cycles, vehicle and engine interface and interaction hazards, engine health management system, engine modification, engine ground start hold down with launch commit criteria, engine altitude start (1 in. start), Multiple altitude restart (less than 1 restart), component, subsystem and system design, manufacturing/ground operation support/pre and post flight check outs and inspection, extensiveness of the development program. We present some sensitivity analysis results for the following subset of the drivers: number of engines for the propulsion stage, single engine total reliability, engine operation duration, engine de-rating or up-rating requirements, engine-out design, catastrophic fraction, preventable failure fraction, unnecessary shutdown fraction, and engine health management system implementation (basic redlines and more advanced health management systems).

  9. Getting to First Flight: Equipping Space Engineers to Break the Start-Stop-Restart Cycle

    NASA Technical Reports Server (NTRS)

    Singer, Christopher E.; Dumbacher, Daniel L.

    2010-01-01

    The National Aeronautics and Space Administration s (NASA s) history is built on a foundation of can-do strength, while pointing to the Saturn/Apollo Moon missions in the 1960s and 1970s as its apex a sentiment that often overshadows the potential that lies ahead. The chronicle of America s civil space agenda is scattered with programs that got off to good starts with adequate resources and vocal political support but that never made it past a certain milestone review, General Accountability Office report, or Congressional budget appropriation. Over the decades since the fielding of the Space Shuttle in the early 1980s, a start-stop-restart cycle has intervened due to many forces. Despite this impediment, the workforce has delivered engineering feats such as the International Space Station and numerous Shuttle and science missions, which reflect a trend in the early days of the Exploration Age that called for massive infrastructure and matching capital allocations. In the new millennium, the aerospace industry must respond to transforming economic climates, the public will, national agendas, and international possibilities relative to scientific exploration beyond Earth s orbit. Two pressing issues - workforce transition and mission success - are intertwined. As this paper will address, U.S. aerospace must confront related workforce development and industrial base issues head on to take space exploration to the next level. This paper also will formulate specific strategies to equip space engineers to move beyond the seemingly constant start-stop-restart mentality to plan and execute flight projects that actually fly.

  10. Saturn Apollo Program

    NASA Image and Video Library

    1967-01-01

    This cutaway illustration shows the Saturn V S-IVB (third) stage with the callouts of its major components. When the S-II (second) stage of the powerful Saturn V rocket burnt out and was separated the remaining units approached orbit around the Earth. Injection into the desired orbit was attaineded as the S-IVB (third stage) was ignited and burnt. The S-IVB stage was powered by a single 200,000-pound thrust J-2 engine and had a re-start capability built in for its J-2 engine. The S-IVB restarted to speed the Apollo spacecraft to escape velocity injecting it and the astronauts into a moon trajectory.

  11. Task 12 data dump (phase 2) OME integrated thrust chamber test report

    NASA Technical Reports Server (NTRS)

    Tobin, R. D.; Pauckert, R. P.

    1974-01-01

    The characteristics and performance of the orbit maneuvering engine for the space shuttle are discussed. Emphasis is placed on the regeneratively cooled thrust chamber of the engine. Tests were conducted to determine engine operating parameters during the start, shutdown, and restart. Characteristics of the integrated thrust chamber and the performance and thermal conditions for blowdown operation without supplementary boundary layer cooling were investigated. The results of the test program are presented.

  12. Propulsion system tests on a full scale Centaur vehicle to investigate 3-burn mission capability of the D-lT configuration

    NASA Technical Reports Server (NTRS)

    Groesbeck, W. A.; Baud, K. M.; Lacovic, R. F.; Tabata, W. K.; Szabo, S. V., Jr.

    1974-01-01

    Propulsion system tests were conducted on a full scale Centaur vehicle to investigate system capability of the proposed D-lT configuration for a three-burn mission. This particular mission profile requires that the engines be capable of restarting and firing for a final maneuver after a 5-1/2-hour coast to synchronous orbit. The thermal conditioning requirements of the engine and propellant feed system components for engine start under these conditions were investigated. Performance data were also obtained on the D-lT type computer controlled propellant tank pressurization system. The test results demonstrated that the RL-10 engines on the Centaur vehicle could be started and run reliably after being thermally conditioned to predicted engine start conditions for a one, two and three burn mission. Investigation of the thermal margins also indicated that engine starts could be accomplished at the maximum predicted component temperature conditions with prestart durations less than planned for flight.

  13. Analysis of False Starts in Spontaneous Speech.

    ERIC Educational Resources Information Center

    O'Shaughnessy, Douglas

    A primary difference between spontaneous speech and read speech concerns the use of false starts, where a speaker interrupts the flow of speech to restart his or her utterance. A study examined the acoustic aspects of such restarts in a widely-used speech database, examining approximately 1000 utterances, about 10% of which contained a restart.…

  14. 40 CFR 85.2210 - Engine restart 2500 rpm/idle test-EPA 81.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Engine restart 2500 rpm/idle test-EPA... Warranty Short Tests § 85.2210 Engine restart 2500 rpm/idle test—EPA 81. (a)(1) General calendar year... engines. (ii) In a state for which the Administrator has approved a State Implementation Plan revision...

  15. ReSTART: A Novel Framework for Resource-Based Triage in Mass-Casualty Events.

    PubMed

    Mills, Alex F; Argon, Nilay T; Ziya, Serhan; Hiestand, Brian; Winslow, James

    2014-01-01

    Current guidelines for mass-casualty triage do not explicitly use information about resource availability. Even though this limitation has been widely recognized, how it should be addressed remains largely unexplored. The authors present a novel framework developed using operations research methods to account for resource limitations when determining priorities for transportation of critically injured patients. To illustrate how this framework can be used, they also develop two specific example methods, named ReSTART and Simple-ReSTART, both of which extend the widely adopted triage protocol Simple Triage and Rapid Treatment (START) by using a simple calculation to determine priorities based on the relative scarcity of transportation resources. The framework is supported by three techniques from operations research: mathematical analysis, optimization, and discrete-event simulation. The authors? algorithms were developed using mathematical analysis and optimization and then extensively tested using 9,000 discrete-event simulations on three distributions of patient severity (representing low, random, and high acuity). For each incident, the expected number of survivors was calculated under START, ReSTART, and Simple-ReSTART. A web-based decision support tool was constructed to help providers make prioritization decisions in the aftermath of mass-casualty incidents based on ReSTART. In simulations, ReSTART resulted in significantly lower mortality than START regardless of which severity distribution was used (paired t test, p<.01). Mean decrease in critical mortality, the percentage of immediate and delayed patients who die, was 8.5% for low-acuity distribution (range ?2.2% to 21.1%), 9.3% for random distribution (range ?0.2% to 21.2%), and 9.1% for high-acuity distribution (range ?0.7% to 21.1%). Although the critical mortality improvement due to ReSTART was different for each of the three severity distributions, the variation was less than 1 percentage point, indicating that the ReSTART policy is relatively robust to different severity distributions. Taking resource limitations into account in mass-casualty situations, triage has the potential to increase the expected number of survivors. Further validation is required before field implementation; however, the framework proposed in here can serve as the foundation for future work in this area. 2014.

  16. Breaking the Vicious Start-Stop-Restart Cycle

    NASA Technical Reports Server (NTRS)

    Singer, Christopher E.

    2011-01-01

    NASA's history is built on a foundation of can-do strength, while pointing to the Apollo Moon missions in the 1960s and 1970s as its apex a sentiment that often overshadows the potential in store. The chronicle of America s civil space adventure is scattered with programs that got off to good starts with adequate resources and vocal political support but that never made it past a certain milestone review, General Accountability Office report, or Congressional budget appropriation. Over the decades since the fielding of the Space Shuttle in the early 1980s, a start-stop-restart cycle has intervened due to many forces. Despite this impediment, the workforce has delivered feats such as the International Space Station and numerous Shuttle and science missions, which reflect a trend in the early days of the Exploration Age that called for massive infrastructure and matching capital allocations. In the new millennium, the aerospace industry must respond to transforming economic climates, the public will, national agendas, and international possibilities relative to scientific exploration beyond Earth's orbit. Two pressing issues workforce transition and mission success are intertwined. As this briefing will show, U.S. aerospace must confront related workforce development and industrial base issues head on to take space exploration to the next level. This briefing also will formulate specific strategies to equip space engineers to move beyond the seemingly constant start-stop-restart mentality to plan and execute flight projects that actually fly.

  17. Saturn Apollo Program

    NASA Image and Video Library

    1963-01-01

    Smokeless flame juts from the diffuser of a unique vacuum chamber in which the upper stage rocket engine, the hydrogen fueled J-2, was tested at a simulated space altitude in excess of 60,000 feet. The smoke you see is actually steam. In operation, vacuum is established by injecting steam into the chamber and is maintained by the thrust of the engine firing through the diffuser. The engine was tested in this environment for start, stop, coast, restart, and full-duration operations. The chamber was located at Rocketdyne's Propulsion Field Laboratory, in the Santa Susana Mountains, near Canoga Park, California. The J-2 engine was developed by Rocketdyne for the Marshall Space Flight Center.

  18. Project Re-Start. A Program for Homeless Adults.

    ERIC Educational Resources Information Center

    Pelzer, Dagmar F.; And Others

    Project Re-Start, of the Dade County Public Schools in Florida, was funded under the Adult Education Act and the Stewart B. McKinney Homeless Assistance Act. Classes in literacy skills, General Educational Development (GED) preparation, English for speakers of other languages, employability skills, and life coping skills were conducted at most of…

  19. Quick look test report: MPT static firing no. 2 test MPT-S2

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The three engine cluster was fired at 70 percent power level for a nominal 15 seconds to evaluate the integrated performance of the main propulsion system. Engine ignition occurred at approximately 1403 with the planned mainstage duration achieved for all three engines. Operation of all systems was as expected with the exception of the recirculation pumps. The pumps were started while the propellant loading was in fast fill, but they cavitated and lost head at the termination of fast fill. The pumps were subsequently restarted after pressurizing the tank and draining back propellant to get good quality. Post test inspection of the engines revealed some discoloration on the inside of the thrust chamber and distorted drain lines for engine #2.

  20. 40 CFR 1065.526 - Repeating void modes or test intervals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... or test intervals in any circumstances that would be inconsistent with good engineering judgment. For... that include hybrid energy storage features or emission controls that involve physical or chemical... shut down, restart the engine. (2) Use good engineering judgment to restart the test sequence using the...

  1. 40 CFR 1065.526 - Repeating void modes or test intervals.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... or test intervals in any circumstances that would be inconsistent with good engineering judgment. For... that include hybrid energy storage features or emission controls that involve physical or chemical... shut down, restart the engine. (2) Use good engineering judgment to restart the test sequence using the...

  2. Analysis of the Functionality of Refillable Propellant Management Devices (PMD)

    NASA Astrophysics Data System (ADS)

    Winkelmann, Yvonne; Gaulke, Diana; Dreyer, Michael E.

    In order to restart a stage of a spacecraft it is necessary to position the liquid stable over the tank outlet. The gas-or vapor-free provision of the thrusters for the main engine start-up can be accomplished by the use of propellant management devices (PMDs). A propellant refillable reservoir (PRR) will supply the engine with the required amount of liquid propellant until the liquid outside the PRR has settled at the bottom of the tank. Hence, the reservoir will be refilled and the main engine can be restarted. This technique has been applied in case of storable propellants yet, e.g. in satellites or ATVs. For the application in a cryogenic upper stage demonstration and validation tests are still necessary. Ground experiments to simulate propulsed phases are evaluated. To demonstrate the functionality under propulsed conditions first filling, draining and draining with a constant fill level of the tank (refilling) are analyzed. Different inflows with respect to filling and varied outflow rates for the draining tests are investigated. Pressure losses in the LOX-PMD are measured during draining and compared to a previously accomplished estimation with an one-dimensional streamtube theory.

  3. Nature of radio feature formed by re-started jet activity in 3C 84 and its relation with γ-ray emissions

    NASA Astrophysics Data System (ADS)

    Nagai, H.; Chida, H.; Kino, M.; Orienti, M.; D'Ammando, F.; Giovannini, G.; Hiura, K.

    2016-02-01

    Re-started jet activity occurred in the bright nearby radio source 3C 84 in about 2005. The re-started jet is forming a prominent component (namely C3) at the tip of jet. The component has showed an increase in radio flux density for more than 7 years while the radio spectrum remains optically thin. This suggests that the component is the head of a radio lobe including a hotspot where the particle acceleration occurs. Thus, 3C 84 is a unique laboratory to study the physical properties at the very early stage of radio source evolution. Another important aspect is that high energy and very high energy γ-ray emissions are detected from this source. The quest for the site of γ-ray emission is quite important to obtain a better understanding of γ-ray emission mechanisms in radio galaxies. In this paper, we review the observational results from very long baseline interferometry (VLBI) monitoring of 3C 84 reported in series of our previous papers. We argue the nature of re-started jet/radio lobe and its relation with high-energy emission.

  4. Technicians Manufacture a Nozzle for the Kiwi B-1-B Engine

    NASA Image and Video Library

    1964-05-21

    Technicians manufacture a nozzle for the Kiwi B-1-B nuclear rocket engine in the Fabrication Shop’s vacuum oven at the National Aeronautics and Space Administration (NASA) Lewis Research Center. The Nuclear Engine for Rocket Vehicle Applications (NERVA) was a joint NASA and Atomic Energy Commission (AEC) endeavor to develop a nuclear-powered rocket for both long-range missions to Mars and as a possible upper-stage for the Apollo Program. The early portion of the program consisted of basic reactor and fuel system research. This was followed by a series of Kiwi reactors built to test basic nuclear rocket principles in a non-flying nuclear engine. The next phase, NERVA, would create an entire flyable engine. The final phase of the program, called Reactor-In-Flight-Test, would be an actual launch test. The AEC was responsible for designing the nuclear reactor and overall engine. NASA Lewis was responsible for developing the liquid-hydrogen fuel system. The turbopump, which pumped the fuels from the storage tanks to the engine, was the primary tool for restarting the engine. The NERVA had to be able to restart in space on its own using a safe preprogrammed startup system. Lewis researchers endeavored to design and test this system. This non-nuclear Kiwi engine, seen here, was being prepared for tests at Lewis’ High Energy Rocket Engine Research Facility (B-1) located at Plum Brook Station. The tests were designed to start an unfueled Kiwi B-1-B reactor and its Aerojet Mark IX turbopump without any external power.

  5. McrEngine: A Scalable Checkpointing System Using Data-Aware Aggregation and Compression

    DOE PAGES

    Islam, Tanzima Zerin; Mohror, Kathryn; Bagchi, Saurabh; ...

    2013-01-01

    High performance computing (HPC) systems use checkpoint-restart to tolerate failures. Typically, applications store their states in checkpoints on a parallel file system (PFS). As applications scale up, checkpoint-restart incurs high overheads due to contention for PFS resources. The high overheads force large-scale applications to reduce checkpoint frequency, which means more compute time is lost in the event of failure. We alleviate this problem through a scalable checkpoint-restart system, mcrEngine. McrEngine aggregates checkpoints from multiple application processes with knowledge of the data semantics available through widely-used I/O libraries, e.g., HDF5 and netCDF, and compresses them. Our novel scheme improves compressibility ofmore » checkpoints up to 115% over simple concatenation and compression. Our evaluation with large-scale application checkpoints show that mcrEngine reduces checkpointing overhead by up to 87% and restart overhead by up to 62% over a baseline with no aggregation or compression.« less

  6. 46 CFR 58.25-30 - Automatic restart.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... auxiliary steering gear and each power actuating system must restart automatically when electrical power is... 46 Shipping 2 2014-10-01 2014-10-01 false Automatic restart. 58.25-30 Section 58.25-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY...

  7. 46 CFR 58.25-30 - Automatic restart.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... auxiliary steering gear and each power actuating system must restart automatically when electrical power is... 46 Shipping 2 2013-10-01 2013-10-01 false Automatic restart. 58.25-30 Section 58.25-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY...

  8. 46 CFR 58.25-30 - Automatic restart.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... auxiliary steering gear and each power actuating system must restart automatically when electrical power is... 46 Shipping 2 2012-10-01 2012-10-01 false Automatic restart. 58.25-30 Section 58.25-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY...

  9. 46 CFR 58.25-30 - Automatic restart.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... auxiliary steering gear and each power actuating system must restart automatically when electrical power is... 46 Shipping 2 2011-10-01 2011-10-01 false Automatic restart. 58.25-30 Section 58.25-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY...

  10. 46 CFR 58.25-30 - Automatic restart.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... auxiliary steering gear and each power actuating system must restart automatically when electrical power is... 46 Shipping 2 2010-10-01 2010-10-01 false Automatic restart. 58.25-30 Section 58.25-30 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY...

  11. Re-starting smoking in the postpartum period after receiving a smoking cessation intervention: a systematic review.

    PubMed

    Jones, Matthew; Lewis, Sarah; Parrott, Steve; Wormall, Stephen; Coleman, Tim

    2016-06-01

    In pregnant smoking cessation trial participants, to estimate (1) among women abstinent at the end of pregnancy, the proportion who re-start smoking at time-points afterwards (primary analysis) and (2) among all trial participants, the proportion smoking at the end of pregnancy and at selected time-points during the postpartum period (secondary analysis). Trials identified from two Cochrane reviews plus searches of Medline and EMBASE. Twenty-seven trials were included. The included trials were randomized or quasi-randomized trials of within-pregnancy cessation interventions given to smokers who reported abstinence both at end of pregnancy and at one or more defined time-points after birth. Outcomes were validated biochemically and self-reported continuous abstinence from smoking and 7-day point prevalence abstinence. The primary random-effects meta-analysis used longitudinal data to estimate mean pooled proportions of re-starting smoking; a secondary analysis used cross-sectional data to estimate the mean proportions smoking at different postpartum time-points. Subgroup analyses were performed on biochemically validated abstinence. The pooled mean proportion re-starting at 6 months postpartum was 43% [95% confidence interval (CI) = 16-72%, I(2)  = 96.7%] (11 trials, 571 abstinent women). The pooled mean proportion smoking at the end of pregnancy was 87% (95% CI = 84-90%, I(2)  = 93.2%) and 94% (95% CI = 92-96%, I(2)  = 88%) at 6 months postpartum (23 trials, 9262 trial participants). Findings were similar when using biochemically validated abstinence. In clinical trials of smoking cessation interventions during pregnancy only 13% are abstinent at term. Of these, 43% re-start by 6 months postpartum. © 2016 The Authors. Addiction published by John Wiley & Sons Ltd on behalf of Society for the Study of Addiction.

  12. 40 CFR 85.2211 - Engine restart idle test-EPA 81.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Engine restart idle test-EPA 81. 85.2211 Section 85.2211 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF AIR POLLUTION FROM MOBILE SOURCES Emission Control System Performance Warranty Short...

  13. Characterization of fine particle and gaseous emissions during school bus idling.

    PubMed

    Kinsey, J S; Williams, D C; Dong, Y; Logan, R

    2007-07-15

    The particulate matter (PM) and gaseous emissions from six diesel school buses were determined over a simulated waiting period typical of schools in the northeastern U.S. Testing was conducted for both continuous idle and hot restart conditions using a suite of on-line particle and gas analyzers installed in the U.S. Environmental Protection Agency's Diesel Emissions Aerosol Laboratory. The specific pollutants measured encompassed total PM-2.5 mass (PM < or = 2.5 microm in aerodynamic diameter), PM-2.5 number concentration, particle size distribution, particle-surface polycyclic aromatic hydrocarbons (PAHs), and a tracer gas (1,1,1,2,3,3,3-heptafluoropropane) in the diluted sample stream. Carbon monoxide (CO), carbon dioxide, nitrogen oxides (NO(x)), total hydrocarbons (THC), oxygen, formaldehyde, and the tracer gas were also measured in the raw exhaust. Results of the study showed little difference in the measured emissions between a 10 min post-restart idle and a 10 min continuous idle with the exception of THC and formaldehyde. However, an emissions pulse was observed during engine restart. A predictive equation was developed from the experimental data, which allows a comparison between continuous idle and hot restart for NO(x), CO, PM2.5, and PAHs and which considers factors such as the restart emissions pulse and periods when the engine is not running. This equation indicates that restart is the preferred operating scenario as long as there is no extended idling after the engine is restarted.

  14. SERT 2 hollow cathode multiple restarts in space

    NASA Technical Reports Server (NTRS)

    Kerslake, W. R.; Finke, R. C.

    1973-01-01

    Future missions, both station keeping and primary electric propulsion, will require multiple thrust restarts after periods of inactivity from a few hours to over one year. Although not a part of the original SERT 2 (Space Electric Rocket Test) flight objective, the opportunity to demonstrate multiple cathode restarts in space became available following completion of thruster running. Both neutralizer and main cathodes of each flight thruster were restarted repeatedly following storage periods up to 490 days. No deterioration of cathode heaters was noted nor was any change required in starting voltages or currents.

  15. Volvo Penta 4.3 GL E15 Emissions and Durability Test

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zoubul, G.; Cahoon, M.; Kolb, R.

    2011-10-01

    A new Volvo Penta carbureted 4.3 GL engine underwent emissions and dynamometer durability testing from break-in to expected end of life using an accelerated ICOMIA marine emissions cycle and E15 fuel. Only ethanol content was controlled. All aging used splash-blended E15 fuel. Exhaust emissions, exhaust gas temperature, torque, power, barometric pressure, air temperature, and fuel flow were measured at five intervals using site-blended E15 aging fuel and certification fuel (E0). The durability test cycle showed no noticeable impact on mechanical durability or engine power. Emissions performance degraded beyond the certification limit for this engine family, mostly occurring by 28% ofmore » expected life. Such degradation is inconsistent with prior experience. Comparisons showed that E15 resulted in lower CO and HC, but increased NOX, as expected for non-feedback-controlled carbureted engines with increased oxygen in the fuel. Fuel consumption also increased with E15 compared with E0. Throughout testing, poor starting characteristics were exhibited on E15 fuel for hot re-start and cold-start. Cranking time to start and smooth idle was roughly doubled compared with typical E0 operation. The carburetor was factory-set for lean operation to ensure emissions compliance. Test protocols did not include carburetor adjustment to account for increased oxygen in the E15 fuel.« less

  16. Advanced Transportation System Studies. Technical Area 3: Alternate Propulsion Subsystem Concepts. Volume 1; Executive Summary

    NASA Technical Reports Server (NTRS)

    Levack, Daniel J. H.

    2000-01-01

    The Alternate Propulsion Subsystem Concepts contract had seven tasks defined that are reported under this contract deliverable. The tasks were: FAA Restart Study, J-2S Restart Study, Propulsion Database Development. SSME Upper Stage Use. CERs for Liquid Propellant Rocket Engines. Advanced Low Cost Engines, and Tripropellant Comparison Study. The two restart studies, F-1A and J-2S, generated program plans for restarting production of each engine. Special emphasis was placed on determining changes to individual parts due to obsolete materials, changes in OSHA and environmental concerns, new processes available, and any configuration changes to the engines. The Propulsion Database Development task developed a database structure and format which is easy to use and modify while also being comprehensive in the level of detail available. The database structure included extensive engine information and allows for parametric data generation for conceptual engine concepts. The SSME Upper Stage Use task examined the changes needed or desirable to use the SSME as an upper stage engine both in a second stage and in a translunar injection stage. The CERs for Liquid Engines task developed qualitative parametric cost estimating relationships at the engine and major subassembly level for estimating development and production costs of chemical propulsion liquid rocket engines. The Advanced Low Cost Engines task examined propulsion systems for SSTO applications including engine concept definition, mission analysis. trade studies. operating point selection, turbomachinery alternatives, life cycle cost, weight definition. and point design conceptual drawings and component design. The task concentrated on bipropellant engines, but also examined tripropellant engines. The Tripropellant Comparison Study task provided an unambiguous comparison among various tripropellant implementation approaches and cycle choices, and then compared them to similarly designed bipropellant engines in the SSTO mission This volume overviews each of the tasks giving its objectives, main results. and conclusions. More detailed Final Task Reports are available on each individual task.

  17. Increased capability gas generator for Space Shuttle APU. Development/hot restart test report

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The design, fabrication, and testing of an increased capability gas generator for use in space shuttles are described. Results show an unlimited hot restart capability in the range of feed pressures from 400 psi to 80 psi. Effects of vacuum on hot restart were not addressed, and only beginning-of-life bed conditions were tested. No starts with bubbles were performed. A minimum expected life of 35 hours or more is projected, and the design will maintain a surface temperature of 350 F or more.

  18. Home Energy Saver

    Science.gov Websites

    Help | About | Privacy | Media Room | Feedback Start Describe Compare Upgrade Learn Error: Your Session Timed Out, Please click the start button to restart. Write down your session id. Environmental

  19. 78 FR 46395 - Self-Regulatory Organizations; Chicago Board Options Exchange, Incorporated; Notice of Filing and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-31

    ... after logon 10:00:020--CAS receives a message from Client Application --Counter re-starts 10:00:070--No... receives a message from Client Application --Counter restarts (2) 10:00:000--Heartbeat Request sent to Client Application within login 10:00:020--CAS receives a message from Client Application --Counter re...

  20. The REstart or STop Antithrombotics Randomised Trial (RESTART) after stroke due to intracerebral haemorrhage: study protocol for a randomised controlled trial.

    PubMed

    Al-Shahi Salman, Rustam; Dennis, Martin S; Murray, Gordon D; Innes, Karen; Drever, Jonathan; Dinsmore, Lynn; Williams, Carol; White, Philip M; Whiteley, William N; Sandercock, Peter A G; Sudlow, Cathie L M; Newby, David E; Sprigg, Nikola; Werring, David J

    2018-03-05

    For adults surviving stroke due to spontaneous (non-traumatic) intracerebral haemorrhage (ICH) who had taken an antithrombotic (i.e. anticoagulant or antiplatelet) drug for the prevention of vaso-occlusive disease before the ICH, it is unclear whether starting antiplatelet drugs results in an increase in the risk of recurrent ICH or a beneficial net reduction of all serious vascular events compared to avoiding antiplatelet drugs. The REstart or STop Antithrombotics Randomised Trial (RESTART) is an investigator-led, randomised, open, assessor-blind, parallel-group, randomised trial comparing starting versus avoiding antiplatelet drugs for adults surviving antithrombotic-associated ICH at 122 hospital sites in the United Kingdom. RESTART uses a central, web-based randomisation system using a minimisation algorithm, with 1:1 treatment allocation to which central research staff are masked. Central follow-up includes annual postal or telephone questionnaires to participants and their general (family) practitioners, with local provision of information about adverse events and outcome events. The primary outcome is recurrent symptomatic ICH. The secondary outcomes are: symptomatic haemorrhagic events; symptomatic vaso-occlusive events; symptomatic stroke of uncertain type; other fatal events; modified Rankin Scale score; adherence to antiplatelet drug(s). The magnetic resonance imaging (MRI) sub-study involves the conduct of brain MRI according to a standardised imaging protocol before randomisation to investigate heterogeneity of treatment effect according to the presence of brain microbleeds. Recruitment began on 22 May 2013. The target sample size is at least 720 participants in the main trial (at least 550 in the MRI sub-study). Final results of RESTART will be analysed and disseminated in 2019. ISRCTN71907627 ( www.isrctn.com/ISRCTN71907627 ). Prospectively registered on 25 April 2013.

  1. Reasons for non-recruitment of eligible patients to a randomised controlled trial of secondary prevention after intracerebral haemorrhage: observational study.

    PubMed

    Maxwell, Amy E; MacLeod, Mary Joan; Joyson, Anu; Johnson, Sharon; Ramadan, Hawraman; Bellfield, Ruth; Byrne, Anthony; McGhee, Caroline; Rudd, Anthony; Price, Fiona; Vasileiadis, Evangelos; Holden, Melinda; Hewitt, Jonathan; Carpenter, Michael; Needle, Ann; Valentine, Stacey; Patel, Farzana; Harrington, Frances; Mudd, Paul; Emsley, Hedley; Gregary, Bindu; Kane, Ingrid; Muir, Keith; Tiwari, Divya; Owusu-Agyei, Peter; Temple, Natalie; Sekaran, Lakshmanan; Ragab, Suzanne; England, Timothy; Hedstrom, Amanda; Jones, Phil; Jones, Sarah; Doherty, Mandy; McCarron, Mark O; Cohen, David L; Tysoe, Sharon; Al-Shahi Salman, Rustam

    2017-04-05

    Recruitment to randomised prevention trials is challenging, not least for intracerebral haemorrhage (ICH) associated with antithrombotic drug use. We investigated reasons for not recruiting apparently eligible patients at hospital sites that keep screening logs in the ongoing REstart or STop Antithrombotics Randomised Trial (RESTART), which seeks to determine whether to start antiplatelet drugs after ICH. By the end of May 2015, 158 participants had been recruited at 108 active sites in RESTART. The trial coordinating centre invited all sites that kept screening logs to submit screening log data, followed by one reminder. We checked the integrity of data, focused on the completeness of data about potentially eligible patients and categorised the reasons they were not randomised. Of 108 active sites, 39 (36%) provided usable screening log data over a median of ten (interquartile range = 5-13) months of recruitment per site. During this time, sites screened 633 potentially eligible patients and randomised 53 (8%) of them. The main reasons why 580 patients were not randomised were: 43 (7%) patients started anticoagulation, 51 (9%) patients declined, 148 (26%) patients' stroke physicians were not uncertain about using antiplatelet drugs, 162 (28%) patients were too unwell and 176 (30%) patients were not randomised due to other reasons. RESTART recruited ~8% of eligible patients. If more physicians were uncertain about the therapeutic dilemma that RESTART is addressing, RESTART could have recruited up to four times as many participants. The trial coordinating centre continues to engage with physicians about their uncertainty. EU Clinical Trials, EudraCT 2012-003190-26 . Registered on 3 July 2012.

  2. Prevention: The Best Treatment for Back Pain

    MedlinePlus

    ... you are re-starting an exercise routine , start low and slow. See how your body adapts before increasing time or intensity. If taking preventive measures do not prevent back pain, or an existing condition worsens, a visit to ...

  3. Checkpoint and restart procedures for single and multi-stage structural model analysis in NASTRAN/COSMIC on a CDC 176

    NASA Technical Reports Server (NTRS)

    Camp, George H.; Fallon, Dennis J.

    1987-01-01

    The Underwater Explosions Research Division (UERD) of the David Taylor Naval Ship Research and Development Center makes extensive use of NASTRAN/COSMIC on a CDC 176 to evaluate the structural response of ship structures subjected to underwater explosion shock loadings in the time domain. As relatively new users, UERD engineers have experienced difficulties with the checkpoint/restart feature because of the vague instructions in the user manual. Working procedures for the application of the checkpoint/restart feature to the transient analysis using NASTRAN/COSMIC are illustrated.

  4. Saturn Apollo Program

    NASA Image and Video Library

    1967-01-01

    This is a cutaway illustration of the Saturn V launch vehicle with callouts of the major components. The Saturn V is the largest and most powerful launch vehicle developed in the United States. It was a three stage rocket, 363 feet in height, used for sending American astronauts to the moon and for placing the Skylab in Earth orbit. The Saturn V was designed to perform Earth orbital missions through the use of the first two stages, while all three stages were used for lunar expeditions. The S-IC stage (first stage) was powered by five F- engines, which burned kerosene and liquid oxygen to produce more than 7,500,000 pounds of thrust. The S-II (second) stage was powered by five J-2 engines, that burned liquid hydrogen and liquid oxygen and produced 1,150,000 pounds thrust. The S-IVB (third) stage used one J-2 engine, producing 230,000 pounds of thrust, with a re-start capability. The Marshall Space Flight Center and its contractors designed, developed, and assembled the Saturn V launch vehicle stages.

  5. 40 CFR 1065.526 - Repeating of void modes or test intervals.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... or test intervals in any circumstances that would be inconsistent with good engineering judgment. For... that include hybrid energy storage features or emission controls that involve physical or chemical... follows: (1) If the engine has stalled or been shut down, restart the engine. (2) Use good engineering...

  6. Rocketdyne - J-2 Saturn V 2nd and 3rd Stage Engine. Chapter 2, Appendix D

    NASA Technical Reports Server (NTRS)

    Coffman, Paul

    2009-01-01

    The J-2 engine was unique in many respects. Technology was not nearly as well-developed in oxygen/hydrogen engines at the start of the J-2 project. As a result, it experienced a number of "teething" problems. It was used in two stages on the Saturn V vehicle in the Apollo Program, as well as on the later Skylab and Apollo/Soyuz programs. In the Apollo Program, it was used on the S-II stage, which was the second stage of the Saturn V vehicle. There were five J-2 engines at the back end of the S-II Stage. In the S-IV-B stage, it was a single engine, but that single engine had to restart. The Apollo mission called for the entire vehicle to reach orbital velocity in low Earth orbit after the first firing of the Saturn-IV-B stage and, subsequently, to fire a second time to go on to the moon. The engine had to be man-rated (worthy of transporting humans). It had to have a high thrust rate and performance associated with oxygen/hydrogen engines, although there were some compromises there. It had to gimbal for thrust vector control. It was an open-cycle gas generator engine delivering up to 230,000 pounds of thrust.

  7. Advanced transportation system studies technical area 3: Alternate propulsion subsystem concepts, volume 2

    NASA Technical Reports Server (NTRS)

    Levak, Daniel

    1993-01-01

    The Alternate Propulsion Subsystem Concepts contract had five tasks defined for the first year. The tasks were: F-1A Restart Study, J-2S Restart Study, Propulsion Database Development, Space Shuttle Main Engine (SSME) Upper Stage Use, and CER's for Liquid Propellant Rocket Engines. The detailed study results, with the data to support the conclusions from various analyses, are being reported as a series of five separate Final Task Reports. Consequently, this volume only reports the required programmatic information concerning Computer Aided Design Documentation, and New Technology Reports. A detailed Executive Summary, covering all the tasks, is also available as Volume 1.

  8. KSC-08pd1650

    NASA Image and Video Library

    2008-06-10

    CAPE CANAVERAL, Fla. – Auxiliary power unit 3, or APU3, is ready for installation in space shuttle Endeavour for the STS-126 mission. The auxiliary power unit is a hydrazine-fueled, turbine-driven power unit that generates mechanical shaft power to drive a hydraulic pump that produces pressure for the orbiter's hydraulic system. There are three separate APUs, three hydraulic pumps and three hydraulic systems, located in the aft fuselage of the orbiter. When the three auxiliary power units are started five minutes before lift-off, the hydraulic systems are used to position the three main engines for activation, control various propellant valves on the engines and position orbiter aerosurfaces. The auxiliary power units are not operated after the first orbital maneuvering system thrusting period because hydraulic power is no longer required. One power unit is operated briefly one day before deorbit to support checkout of the orbiter flight control system. One auxiliary power unit is restarted before the deorbit thrusting period. The two remaining units are started after the deorbit thrusting maneuver and operate continuously through entry, landing and landing rollout. On STS-126, Endeavour will deliver a multi-purpose logistics module to the International Space Station. Launch is targeted for Nov. 10. Photo credit: NASA/Kim Shiflett

  9. 14 CFR 125.177 - Control of engine rotation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Control of engine rotation. 125.177 Section... Requirements § 125.177 Control of engine rotation. (a) Except as provided in paragraph (b) of this section, each airplane must have a means of individually stopping and restarting the rotation of any engine in...

  10. 14 CFR 121.279 - Control of engine rotation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Control of engine rotation. 121.279 Section... of engine rotation. (a) Except as provided in paragraph (b) of this section, each airplane must have a means of individually stopping and restarting the rotation of any engine in flight. (b) In the...

  11. 14 CFR 121.279 - Control of engine rotation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Control of engine rotation. 121.279 Section... of engine rotation. (a) Except as provided in paragraph (b) of this section, each airplane must have a means of individually stopping and restarting the rotation of any engine in flight. (b) In the...

  12. 14 CFR 125.177 - Control of engine rotation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Control of engine rotation. 125.177 Section... Requirements § 125.177 Control of engine rotation. (a) Except as provided in paragraph (b) of this section, each airplane must have a means of individually stopping and restarting the rotation of any engine in...

  13. 14 CFR 125.177 - Control of engine rotation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Control of engine rotation. 125.177 Section... Requirements § 125.177 Control of engine rotation. (a) Except as provided in paragraph (b) of this section, each airplane must have a means of individually stopping and restarting the rotation of any engine in...

  14. 14 CFR 125.177 - Control of engine rotation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Control of engine rotation. 125.177 Section... Requirements § 125.177 Control of engine rotation. (a) Except as provided in paragraph (b) of this section, each airplane must have a means of individually stopping and restarting the rotation of any engine in...

  15. 14 CFR 121.279 - Control of engine rotation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Control of engine rotation. 121.279 Section... of engine rotation. (a) Except as provided in paragraph (b) of this section, each airplane must have a means of individually stopping and restarting the rotation of any engine in flight. (b) In the...

  16. 14 CFR 121.279 - Control of engine rotation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Control of engine rotation. 121.279 Section... of engine rotation. (a) Except as provided in paragraph (b) of this section, each airplane must have a means of individually stopping and restarting the rotation of any engine in flight. (b) In the...

  17. Digital-computer normal shock position and restart control of a Mach 2.5 axisymmetric mixed-compression inlet

    NASA Technical Reports Server (NTRS)

    Neiner, G. H.; Cole, G. L.; Arpasi, D. J.

    1972-01-01

    Digital computer control of a mixed-compression inlet is discussed. The inlet was terminated with a choked orifice at the compressor face station to dynamically simulate a turbojet engine. Inlet diffuser exit airflow disturbances were used. A digital version of a previously tested analog control system was used for both normal shock and restart control. Digital computer algorithms were derived using z-transform and finite difference methods. Using a sample rate of 1000 samples per second, the digital normal shock and restart controls essentially duplicated the inlet analog computer control results. At a sample rate of 100 samples per second, the control system performed adequately but was less stable.

  18. 77 FR 36211 - Airworthiness Directives; Airbus Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-18

    ... was prompted by reports of two single-engine flame-out events during inclement weather. This proposed... [engine] flame out events attributed to inclement weather occurred on Wide Body (WB) aeroplanes powered... events during inclement weather. We are issuing this AD to prevent a long engine restart sequence after a...

  19. Educational Innovation in the Design of an Online Nuclear Engineering Curriculum

    ERIC Educational Resources Information Center

    Hall, Simin; Jones, Brett D.; Amelink, Catherine; Hu, Deyu

    2013-01-01

    The purpose of this paper is to describe the development and implementation phases of online graduate nuclear engineering courses that are part of the Graduate Nuclear Engineering Certificate program at Virginia Tech. Virginia Tech restarted its nuclear engineering program in the Fall of 2007 with 60 students, and by 2009, the enrollment had grown…

  20. Materials for Liquid Propulsion Systems. Chapter 12

    NASA Technical Reports Server (NTRS)

    Halchak, John A.; Cannon, James L.; Brown, Corey

    2016-01-01

    Earth to orbit launch vehicles are propelled by rocket engines and motors, both liquid and solid. This chapter will discuss liquid engines. The heart of a launch vehicle is its engine. The remainder of the vehicle (with the notable exceptions of the payload and guidance system) is an aero structure to support the propellant tanks which provide the fuel and oxidizer to feed the engine or engines. The basic principle behind a rocket engine is straightforward. The engine is a means to convert potential thermochemical energy of one or more propellants into exhaust jet kinetic energy. Fuel and oxidizer are burned in a combustion chamber where they create hot gases under high pressure. These hot gases are allowed to expand through a nozzle. The molecules of hot gas are first constricted by the throat of the nozzle (de-Laval nozzle) which forces them to accelerate; then as the nozzle flares outwards, they expand and further accelerate. It is the mass of the combustion gases times their velocity, reacting against the walls of the combustion chamber and nozzle, which produce thrust according to Newton's third law: for every action there is an equal and opposite reaction. Solid rocket motors are cheaper to manufacture and offer good values for their cost. Liquid propellant engines offer higher performance, that is, they deliver greater thrust per unit weight of propellant burned. They also have a considerably higher thrust to weigh ratio. Since liquid rocket engines can be tested several times before flight, they have the capability to be more reliable, and their ability to shut down once started provides an extra margin of safety. Liquid propellant engines also can be designed with restart capability to provide orbital maneuvering capability. In some instances, liquid engines also can be designed to be reusable. On the solid side, hybrid solid motors also have been developed with the capability to stop and restart. Solid motors are covered in detail in chapter 11. Liquid rocket engine operational factors can be described in terms of extremes: temperatures ranging from that of liquid hydrogen (-423 F) to 6000 F hot gases; enormous thermal shock (7000 F/sec); large temperature differentials between contiguous components; reactive propellants; extreme acoustic environments; high rotational speeds for turbo machinery and extreme power densities. These factors place great demands on materials selection and each must be dealt with while maintaining an engine of the lightest possible weight. This chapter will describe the design considerations for the materials used in the various components of liquid rocket engines and provide examples of usage and experiences in each.

  1. KSC-08pd1652

    NASA Image and Video Library

    2008-06-10

    CAPE CANAVERAL, Fla. – In Orbiter Processing Facility bay No. 2, technicians begin installation of an auxiliary power unit 3, or APU3, in space shuttle Endeavour for the STS-126 mission. The auxiliary power unit is a hydrazine-fueled, turbine-driven power unit that generates mechanical shaft power to drive a hydraulic pump that produces pressure for the orbiter's hydraulic system. There are three separate APUs, three hydraulic pumps and three hydraulic systems, located in the aft fuselage of the orbiter. When the three auxiliary power units are started five minutes before lift-off, the hydraulic systems are used to position the three main engines for activation, control various propellant valves on the engines and position orbiter aerosurfaces. The auxiliary power units are not operated after the first orbital maneuvering system thrusting period because hydraulic power is no longer required. One power unit is operated briefly one day before deorbit to support checkout of the orbiter flight control system. One auxiliary power unit is restarted before the deorbit thrusting period. The two remaining units are started after the deorbit thrusting maneuver and operate continuously through entry, landing and landing rollout. On STS-126, Endeavour will deliver a multi-purpose logistics module to the International Space Station. Launch is targeted for Nov. 10. Photo credit: NASA/Kim Shiflett

  2. KSC-08pd1651

    NASA Image and Video Library

    2008-06-10

    CAPE CANAVERAL, Fla. – In Orbiter Processing Facility bay No. 2, technicians begin installation of an auxiliary power unit 3, or APU3, in space shuttle Endeavour for the STS-126 mission. The auxiliary power unit is a hydrazine-fueled, turbine-driven power unit that generates mechanical shaft power to drive a hydraulic pump that produces pressure for the orbiter's hydraulic system. There are three separate APUs, three hydraulic pumps and three hydraulic systems, located in the aft fuselage of the orbiter. When the three auxiliary power units are started five minutes before lift-off, the hydraulic systems are used to position the three main engines for activation, control various propellant valves on the engines and position orbiter aerosurfaces. The auxiliary power units are not operated after the first orbital maneuvering system thrusting period because hydraulic power is no longer required. One power unit is operated briefly one day before deorbit to support checkout of the orbiter flight control system. One auxiliary power unit is restarted before the deorbit thrusting period. The two remaining units are started after the deorbit thrusting maneuver and operate continuously through entry, landing and landing rollout. On STS-126, Endeavour will deliver a multi-purpose logistics module to the International Space Station. Launch is targeted for Nov. 10. Photo credit: NASA/Kim Shiflett

  3. KSC-08pd1654

    NASA Image and Video Library

    2008-06-10

    CAPE CANAVERAL, Fla. – In Orbiter Processing Facility bay No. 2, auxiliary power unit 3, or APU3, is in place on space shuttle Endeavour for the STS-126 mission. The auxiliary power unit is a hydrazine-fueled, turbine-driven power unit that generates mechanical shaft power to drive a hydraulic pump that produces pressure for the orbiter's hydraulic system. There are three separate APUs, three hydraulic pumps and three hydraulic systems, located in the aft fuselage of the orbiter. When the three auxiliary power units are started five minutes before lift-off, the hydraulic systems are used to position the three main engines for activation, control various propellant valves on the engines and position orbiter aerosurfaces. The auxiliary power units are not operated after the first orbital maneuvering system thrusting period because hydraulic power is no longer required. One power unit is operated briefly one day before deorbit to support checkout of the orbiter flight control system. One auxiliary power unit is restarted before the deorbit thrusting period. The two remaining units are started after the deorbit thrusting maneuver and operate continuously through entry, landing and landing rollout. On STS-126, Endeavour will deliver a multi-purpose logistics module to the International Space Station. Launch is targeted for Nov. 10. Photo credit: NASA/Kim Shiflett

  4. KSC-08pd1653

    NASA Image and Video Library

    2008-06-10

    CAPE CANAVERAL, Fla. – In Orbiter Processing Facility bay No. 2, technicians install auxiliary power unit 3, or APU3, in space shuttle Endeavour for the STS-126 mission. The auxiliary power unit is a hydrazine-fueled, turbine-driven power unit that generates mechanical shaft power to drive a hydraulic pump that produces pressure for the orbiter's hydraulic system. There are three separate APUs, three hydraulic pumps and three hydraulic systems, located in the aft fuselage of the orbiter. When the three auxiliary power units are started five minutes before lift-off, the hydraulic systems are used to position the three main engines for activation, control various propellant valves on the engines and position orbiter aerosurfaces. The auxiliary power units are not operated after the first orbital maneuvering system thrusting period because hydraulic power is no longer required. One power unit is operated briefly one day before deorbit to support checkout of the orbiter flight control system. One auxiliary power unit is restarted before the deorbit thrusting period. The two remaining units are started after the deorbit thrusting maneuver and operate continuously through entry, landing and landing rollout. On STS-126, Endeavour will deliver a multi-purpose logistics module to the International Space Station. Launch is targeted for Nov. 10. Photo credit: NASA/Kim Shiflett

  5. 78 FR 69367 - Golden Valley Electric Association: Healy Power Plant Unit #2 Restart

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-19

    ...: Deirdre M. Remley, Environmental Protection Specialist, RUS, Water and Environmental Programs, Engineering...: (202) 720-9640 or email: [email protected] . The ROD is also available at RUS's Web site at... additional engineering and financial review, administrative actions and financing that would facilitate GVEA...

  6. 40 CFR 1065.362 - Non-stoichiometric raw exhaust FID O2 interference verification.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications Hydrocarbon... frequency. If you use FID analyzers for raw exhaust measurements from engines that operate in a non...; otherwise restart the procedure at paragraph (d)(4) of this section. (13) Calculate the percent difference...

  7. 40 CFR 1065.362 - Non-stoichiometric raw exhaust FID O2 interference verification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications Hydrocarbon... frequency. If you use FID analyzers for raw exhaust measurements from engines that operate in a non...; otherwise restart the procedure at paragraph (d)(4) of this section. (13) Calculate the percent difference...

  8. Idling Reduction for Personal Vehicles

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2015-05-07

    Fact sheet on reducing engine idling in personal vehicles. Idling your vehicle--running your engine when you're not driving it--truly gets you nowhere. Idling reduces your vehicle's fuel economy, costs you money, and creates pollution. Idling for more than 10 seconds uses more fuel and produces more emissions that contribute to smog and climate change than stopping and restarting your engine does.

  9. Promoting Recruitment using Information Management Efficiently (PRIME): a stepped-wedge, cluster randomised trial of a complex recruitment intervention embedded within the REstart or Stop Antithrombotics Randomised Trial.

    PubMed

    Maxwell, Amy E; Parker, Richard A; Drever, Jonathan; Rudd, Anthony; Dennis, Martin S; Weir, Christopher J; Al-Shahi Salman, Rustam

    2017-12-28

    Few interventions are proven to increase recruitment in clinical trials. Recruitment to RESTART, a randomised controlled trial of secondary prevention after stroke due to intracerebral haemorrhage, has been slower than expected. Therefore, we sought to investigate an intervention to boost recruitment to RESTART. We conducted a stepped-wedge, cluster randomised trial of a complex intervention to increase recruitment, embedded within the RESTART trial. The primary objective was to investigate if the PRIME complex intervention (a recruitment co-ordinator who conducts a recruitment review, provides access to bespoke stroke audit data exports, and conducts a follow-up review after 6 months) increases the recruitment rate to RESTART. We included 72 hospital sites located in England, Wales, or Scotland that were active in RESTART in June 2015. All sites began in the control state and were allocated using block randomisation stratified by hospital location (Scotland versus England/Wales) to start the complex intervention in one of 12 different months. The primary outcome was the number of patients randomised into RESTART per month per site. We quantified the effect of the complex intervention on the primary outcome using a negative binomial, mixed model adjusting for site, December/January months, site location, and background time trends in recruitment rate. We recruited and randomised 72 sites and recorded their monthly recruitment to RESTART over 24 months (March 2015 to February 2017 inclusive), providing 1728 site-months of observations for the primary analysis. The adjusted rate ratio for the number of patients randomised per month after allocation to the PRIME complex intervention versus control time before allocation to the PRIME complex intervention was 1.06 (95% confidence interval 0.55 to 2.03, p = 0.87). Although two thirds of respondents to the 6-month follow-up questionnaire agreed that the audit reports were useful, only six patients were reported to have been randomised using the audit reports. Respondents frequently reported resource and time pressures as being key barriers to running the audit reports. The PRIME complex intervention did not significantly improve the recruitment rate to RESTART. Further research is needed to establish if PRIME might be beneficial at an earlier stage in a prevention trial or for prevention dilemmas that arise more often in clinical practice.

  10. Quantifying the Effects of Idle-Stop Systems on Fuel Economy in Light-Duty Passenger Vehicles

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jeff Wishart; Matthew Shirk

    2012-12-01

    Vehicles equipped with idle-stop (IS) systems are capable of engine shut down when the vehicle is stopped and rapid engine re-start for the vehicle launch. This capability reduces fuel consumption and emissions during periods when the engine is not being utilized to provide propulsion or to power accessories. IS systems are a low-cost and fast-growing technology in the industry-wide pursuit of increased vehicle efficiency, possibly becoming standard features in European vehicles in the near future. In contrast, currently there are only three non-hybrid vehicle models for sale in North America with IS systems and these models are distinctly low-volume models.more » As part of the United States Department of Energy’s Advanced Vehicle Testing Activity, ECOtality North America has tested the real-world effect of IS systems on fuel consumption in three vehicle models imported from Europe. These vehicles were chosen to represent three types of systems: (1) spark ignition with 12-V belt alternator starter; (2) compression ignition with 12-V belt alternator starter; and (3) direct-injection spark ignition, with 12-V belt alternator starter/combustion restart. The vehicles have undergone both dynamometer and on-road testing; the test results show somewhat conflicting data. The laboratory data and the portion of the on-road data in which driving is conducted on a prescribed route with trained drivers produced significant fuel economy improvement. However, the fleet data do not corroborate improvement, even though the data show significant engine-off time. It is possible that the effects of the varying driving styles and routes in the fleet testing overshadowed the fuel economy improvements. More testing with the same driver over routes that are similar with the IS system-enabled and disabled is recommended. There is anecdotal evidence that current Environmental Protection Agency fuel economy test procedures do not capture the fuel economy gains that IS systems produce in real-world driving. The program test results provide information on the veracity of these claims.« less

  11. Tailored dialysis start may allow persistence of residual renal function after graft failure: a case report.

    PubMed

    Piccoli, G B; Motta, D; Gai, M; Mezza, E; Maddalena, E; Bravin, M; Tattoli, F; Consiglio, V; Burdese, M; Bilucaglia, D; Ferrari, A; Segoloni, G P

    2004-11-01

    Restarting dialysis after kidney transplantation is a critical step with psychological and clinical implications. Maintenance of residual renal function a known factor affecting survival in chronic kidney disease, has so far not been investigated after a kidney transplantation. A 54-year-old woman who started dialysis in 1974 (first graft, 1975-1999) received a second "marginal" kidney graft in February 2001 (donor age, 65 years). Her chronic therapy was tacrolimus and steroids. She had a clinical history as follows: nadir creatinine level of 1.5 mg/dL, moderate-severe hypertension, progressive graft dysfunction, nonresponsiveness to addition of mycophenolate, tapering FK levels, and a rescue switch from tacrolimus to rapamycin. From October to December 2003, the creatinine level increased from 2-2.8 to 7 mg/dL. Biopsy specimen showed malignant and "benign" nephrosclerosis, posttransplantation glomerulopathy, and tacrolimus toxicity. Chronic dialysis was started (GFR <3 mL/min). Rapamycin was discontinued. Dialysis was tailored to reach an equivalent renal clearance of >15 mL/min (2 sessions/wk). Blood pressure control improved, nephrotoxic drugs were avoided, and fluid loss was minimized (maximum 500 mL/hr). By this policy, renal function progressively increased to GFR >10 mL/min in May 2004, allowing a once or twice weekly dialysis schedule, with good clinical balance, and obvious advantages for the quality of life. This long-term patient, who restarted dialysis with severely reduced renal function, regained sufficient renal function to allow once weekly dialysis. Thus, careful tailoring of dialysis sessions at the restart of dialysis may allow preservation of residual kidney function, at least in individuals for whom a subsequent graft is unlikely.

  12. Impacts of visuomotor sequence learning methods on speed and accuracy: Starting over from the beginning or from the point of error.

    PubMed

    Tanaka, Kanji; Watanabe, Katsumi

    2016-02-01

    The present study examined whether sequence learning led to more accurate and shorter performance time if people who are learning a sequence start over from the beginning when they make an error (i.e., practice the whole sequence) or only from the point of error (i.e., practice a part of the sequence). We used a visuomotor sequence learning paradigm with a trial-and-error procedure. In Experiment 1, we found fewer errors, and shorter performance time for those who restarted their performance from the beginning of the sequence as compared to those who restarted from the point at which an error occurred, indicating better learning of spatial and motor representations of the sequence. This might be because the learned elements were repeated when the next performance started over from the beginning. In subsequent experiments, we increased the occasions for the repetitions of learned elements by modulating the number of fresh start points in the sequence after errors. The results showed that fewer fresh start points were likely to lead to fewer errors and shorter performance time, indicating that the repetitions of learned elements enabled participants to develop stronger spatial and motor representations of the sequence. Thus, a single or two fresh start points in the sequence (i.e., starting over only from the beginning or from the beginning or midpoint of the sequence after errors) is likely to lead to more accurate and faster performance. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. CECE: A Deep Throttling Demonstrator Cryogenic Engine for NASA's Lunar Lander

    NASA Technical Reports Server (NTRS)

    Giuliano, Victor J.; Leonard, Timothy G.; Adamski, Walter M.; Kim, Tony S.

    2007-01-01

    As one of the first technology development programs awarded under NASA's Vision for Space Exploration, the Pratt & Whitney Rocketdyne (PWR) Deep Throttling, Common Extensible Cryogenic Engine (CECE) program was selected by NASA in November 2004 to begin technology development and demonstration toward a deep throttling, cryogenic Lunar Lander engine for use across multiple human and robotic lunar exploration mission segments with extensibility to Mars. The CECE program leverages the maturity and previous investment of a flight-proven hydrogen/oxygen expander cycle engine, the RL10, to develop and demonstrate an unprecedented combination of reliability, safety, durability, throttlability, and restart capabilities in a high-energy, cryogenic engine. NASA Marshall Space Flight Center and NASA Glenn Research Center personnel were integral design and analysis team members throughout the requirements assessment, propellant studies and the deep throttling demonstrator elements of the program. The testbed selected for the initial deep throttling demonstration phase of this program was a minimally modified RL10 engine, allowing for maximum current production engine commonality and extensibility with minimum program cost. In just nine months from technical program start, CECE Demonstrator No. 1 engine testing in April/May 2006 at PWR's E06 test stand successfully demonstrated in excess of 10:1 throttling of the hydrogen/oxygen expander cycle engine. This test provided an early demonstration of a viable, enabling cryogenic propulsion concept with invaluable system-level technology data acquisition toward design and development risk mitigation for both the subsequent CECE Demonstrator No. 2 program and to the future Lunar Lander Design, Development, Test and Evaluation effort.

  14. Saturn Apollo Program

    NASA Image and Video Library

    1968-01-01

    This image depicts the Saturn V S-IVB (third) stage for the Apollo 10 mission being removed from the Beta Test Stand 1 after its acceptance test at the Douglas Aircraft Company's Sacramento Test Operations (SACTO) facility. After the S-II (second) stage dropped away, the S-IVB (third) stage was ignited and burned for about two minutes to place itself and the Apollo spacecraft into the desired Earth orbit. At the proper time during this Earth parking orbit, the S-IVB stage was re-ignited to speed the Apollo spacecraft to escape velocity injecting it and the astronauts into a moon trajectory. Developed and manufactured by the Douglas Aircraft Company in California, the S-IVB stage measures about 21.5 feet in diameter, about 58 feet in length, and powered by a single 200,000-pound-thrust J-2 engine with a re-start capability. The S-IVB stage was also used on the second stage of the Saturn IB launch vehicle.

  15. Saturn Apollo Program

    NASA Image and Video Library

    1967-01-01

    After the S-II (second) stage dropped away, the S-IVB (third) stage ignited and burned for about two minutes to place itself and the Apollo spacecraft into the desired Earth orbit. At the proper time during this Earth parking orbit, the S-IVB stage was re-ignited to speed the Apollo spacecraft to escape velocity, injecting it and the astronauts into a moon trajectory. Developed and manufactured by the Douglas Aircraft Company in Huntington, California, the S-IVB stage measures about 21.5 feet in diameter, about 58 feet in length and is powered by a single 200,000-pound-thrust J-2 engine with a re-start capability. The S-IVB stage was also used on the second stage of the Saturn IB launch vehicle. The fully-assembled S-IVB (third) stage for the AS-503 (Apollo 8 mission) launch vehicle is pictured in the Douglas' vertical checkout building.

  16. Reorientation of rotating fluid in microgravity environment with and without gravity jitters

    NASA Technical Reports Server (NTRS)

    Hung, R. J.; Lee, C. C.; Shyu, K. L.

    1990-01-01

    In a spacecraft design, the requirements of settled propellant are different for tank pressurization, engine restart, venting, or propellant transfer. The requirement to settle or to position liquid fuel over the outlet end of the spacecraft propellant tank prior main engine restart poses a microgravity fluid behavior problem. In this paper, the dynamical behavior of liquid propellant, fluid reorientation, and propellant resettling have been carried out through the execution of supercomputer CRAY X-MP to simulate the fluid management in a microgravity environment. Results show that the resettlement of fluid can be accomplished more efficiently for fluid in rotating tank than in nonrotating tank, and also better performance for gravity jitters imposed on fluid settlement than without gravity jitters based on the amount of time needed to carry out resettlement period of time between the initiation and termination of geysering.

  17. Development Status of the J-2X

    NASA Technical Reports Server (NTRS)

    Kynard, Mike; Vilja, John

    2008-01-01

    In June 2006, the NASA Marshall Space Flight Center (MSFC) and Pratt & Whitney Rocketdyne began development of an engine for use on the Ares I crew launch vehicle and the Ares V cargo launch vehicle. The development program will be completed in December 2012 at the end of a Design Certification Review and after certification testing of two flight configuration engines. A team of over 600 people within NASA and Pratt & Whitney Rocketdyne are currently working to prepare for the fall 2008 Critical Design Review (CDR), along with supporting an extensive risk mitigation test program. The J-2X will power the Ares I upper stage and the Ares V earth departure stage (EDS). The initial use will be in the Ares I, used to launch the Orion crew exploration vehicle. In this application, it will power the upper stage after being sent aloft on a Space Shuttle-derived. 5-segment solid rocket booster first stage. In this mission. the engine will ignite at altitude and provide the necessary acceleration force to allow the Orion to achieve orbital velocity. The Ares I upper stage, along with the J-2X. will then be expended. On the Ares V. first stage propulsion is provided by five RS-68B engines and two 5-segment boosters similar to the Ares I configuration. In the Ares V mission. the J-2X is first started to power the EDS and its payload. the Altair lunar lander. into earth orbit, then shut-down and get prepared for its next start. The EDS/Altair will remain in a parking orbit, awaiting rendezvous and docking with Orion. Once the two spacecraft are mated, the J-2X will be restarted to achieve earth departure velocity. After powering the Orion and Altair, the EDS will be expended. By using the J-2X Engine in both applications, a significant infrastructure cost savings is realized. Only one engine development is required, and the sustaining engineering and flight support infrastructures can be combined. There is also flexibility for changing, the production and flight manifest because a single production line can support both missions with minimal differences between each engine configuration kit.

  18. Walking a tightrope: clinical use of ibrutinib in mantle cell lymphoma in the elderly.

    PubMed

    Ruella, Marco; Soubeyran, Pierre

    2016-12-02

    Representative clinical case. A 74-year-old male patient was diagnosed with stage 3 mantle cell lymphoma in 2012. Because he was ineligible for intensive treatment (age, previous myocardial infarction [MI]), he received rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) chemoimmunotherapy for 6 cycles (reaching complete response) and then rituximab maintenance (RM) for 2 years. One year after the end of RM, he relapsed with disseminated disease. He was started on ibrutinib 560 mg/day. Two weeks after the start of ibrutinib, he developed grade 3 diarrhea that required interruption of ibrutinib. Two weeks after the regular dose was restarted (month 3), the patient had repeated bleeding (patient was receiving aspirin for previous MI) and had to stop ibrutinib again. Because the patient was in partial response (PR) with lack of disease-associated symptoms, he was restarted on ibrutinib 280 mg/day with no further adverse events, and he had maintained PR at last follow-up (month 9 on ibrutinib). © 2016 by The American Society of Hematology. All rights reserved.

  19. Description and test results of a digital supersonic propulsion system integrated control

    NASA Technical Reports Server (NTRS)

    Batterton, P. G.; Arpasi, D. J.; Baumbick, R. J.

    1976-01-01

    A digitally implemented integrated inlet/engine control system was developed and tested on a mixed compression, Mach 2.5, supersonic inlet and augmented turbofan engine. The control matched engine airflow to available inlet airflow so that in steady state, the shock would be at the desired location, and the overboard bypass doors would be closed. During engine induced transients, such as augmentor lights and cutoffs, the inlet operating point was momentarily changed to a more supercritical point to minimize unstarts. The digital control also provided automatic inlet restart.

  20. Introducing the LHC in the Classroom: An Overview of Education Resources Available

    ERIC Educational Resources Information Center

    Wiener, Gerfried J.; Woithe, Julia; Brown, Alexander; Jende, Konrad

    2016-01-01

    In the context of the recent re-start of CERN's Large Hadron Collider (LHC) and the challenge presented by unidentified falling objects (UFOs), we seek to facilitate the introduction of high energy physics in the classroom. Therefore, this paper provides an overview of the LHC and its operation, highlighting existing education resources, and…

  1. An Application of Cost-Effectiveness Analysis in a Major Defense Acquisition Program: the Decision by the U.S. Department of Defense to Retain the C-17 Transport Aircraft

    DTIC Science & Technology

    2010-12-01

    adding hush kits to dampen the sound of the engines and adding extra material to the fuselage. The cost to restart the C-5 line was estimated at $750...include adding hush kits to dampen the sound of the engines and extra material to the fuselage. A recently completed SAB had recommended that the weep

  2. External fuel vaporization study, phase 1

    NASA Technical Reports Server (NTRS)

    Szetela, E. J.; Chiappetta, L.

    1980-01-01

    A conceptual design study was conducted to devise and evaluate techniques for the external vaporization of fuel for use in an aircraft gas turbine with characteristics similar to the Energy Efficient Engine (E(3)). Three vaporizer concepts were selected and they were analyzed from the standpoint of fuel thermal stability, integration of the vaporizer system into the aircraft engine, engine and vaporizer dynamic response, startup and altitude restart, engine performance, control requirements, safety, and maintenance. One of the concepts was found to improve the performance of the baseline E(3) engine without seriously compromising engine startup and power change response. Increased maintenance is required because of the need for frequent pyrolytic cleaning of the surfaces in contact with hot fuel.

  3. Alkali metal pool boiler life tests for a 25 kWe advanced Stirling conversion system

    NASA Technical Reports Server (NTRS)

    Anderson, W. G.; Rosenfeld, J. H.; Noble, J.

    1991-01-01

    The overall operating temperature and efficiency of solar-powered Stirling engines can be improved by adding an alkali metal pool boiler heat transport system to supply heat more uniformly to the heater head tubes. One issue with liquid metal pool boilers is unstable boiling. Stable boiling is obtained with an enhanced boiling surface containing nucleation sites that promote continuous boiling. Over longer time periods, it is possible that the boiling behavior of the system will change. An 800-h life test was conducted to verify that pool boiling with the chosen fluid/surface combination remains stable as the system ages. The apparatus uses NaK boiling on a - 100 + 140 stainless steel sintered porous layer, with the addition of a small amount of xenon. Pool boiling remained stable to the end of life test. The pool boiler life test included a total of 82 cold starts, to simulate startup each morning, and 60 warm restarts, to simulate cloud cover transients. The behavior of the cold and warm starts showed no significant changes during the life test. In the experiments, the fluid/surface combination provided stable, high-performance boiling at the operating temperature of 700 C. Based on these experiments, a pool boiler was designed for a full-scale 25-kWe Stirling system.

  4. Environmental Testing of the NEXT PM1R Ion Engine

    NASA Technical Reports Server (NTRS)

    Snyder, John S.; Anderson, John R.; VanNoord, Jonathan L.; Soulas, George C.

    2007-01-01

    The NEXT propulsion system is an advanced ion propulsion system presently under development that is oriented towards robotic exploration of the solar system using solar electric power. The subsystem includes an ion engine, power processing unit, feed system components, and thruster gimbal. The Prototype Model engine PM1 was subjected to qualification-level environmental testing in 2006 to demonstrate compatibility with environments representative of anticipated mission requirements. Although the testing was largely successful, several issues were identified including the fragmentation of potting cement on the discharge and neutralizer cathode heater terminations during vibration which led to abbreviated thermal testing, and generation of particulate contamination from manufacturing processes and engine materials. The engine was reworked to address most of these findings, renamed PM1R, and the environmental test sequence was repeated. Thruster functional testing was performed before and after the vibration and thermal-vacuum tests. Random vibration testing, conducted with the thruster mated to the breadboard gimbal, was executed at 10.0 Grms for 2 min in each of three axes. Thermal-vacuum testing included three thermal cycles from 120 to 215 C with hot engine re-starts. Thruster performance was nominal throughout the test program, with minor variations in a few engine operating parameters likely caused by facility effects. There were no significant changes in engine performance as characterized by engine operating parameters, ion optics performance measurements, and beam current density measurements, indicating no significant changes to the hardware as a result of the environmental testing. The NEXT PM1R engine and the breadboard gimbal were found to be well-designed against environmental requirements based on the results reported herein. The redesigned cathode heater terminations successfully survived the vibration environments. Based on the results of this test program and confidence in the engineering solutions available for the remaining findings of the first test program, specifically the particulate contamination, the hardware environmental qualification program can proceed with confidence

  5. Progress and opportunities for tissue-engineered skin

    NASA Astrophysics Data System (ADS)

    MacNeil, Sheila

    2007-02-01

    Tissue-engineered skin is now a reality. For patients with extensive full-thickness burns, laboratory expansion of skin cells to achieve barrier function can make the difference between life and death, and it was this acute need that drove the initiation of tissue engineering in the 1980s. A much larger group of patients have ulcers resistant to conventional healing, and treatments using cultured skin cells have been devised to restart the wound-healing process. In the laboratory, the use of tissue-engineered skin provides insight into the behaviour of skin cells in healthy skin and in diseases such as vitiligo, melanoma, psoriasis and blistering disorders.

  6. 49 CFR 571.102 - Standard No. 102; Transmission shift position sequence, starter interlock, and transmission...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... position. S3.1.2Transmission braking effect. In vehicles having more than one forward transmission gear... driver has activated the vehicle's propulsion system: (a) The engine may stop and restart automatically... activated the vehicle's propulsion system if the vehicle can meet the requirements specified in paragraphs...

  7. 77 FR 1080 - Notice of Intent To Prepare an Environmental Impact Statement for the Proposed Copper Flat Mine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-09

    ...] Notice of Intent To Prepare an Environmental Impact Statement for the Proposed Copper Flat Mine Plan of... the Draft EIS. ADDRESSES: You may submit comments related to the Copper Flat EIS Project by any of the... New Mexico Copper Corp. to re-start the Copper Flat Mine located in Sierra County, New Mexico. The...

  8. Etanercept and adalimumab treatment patterns in psoriatic arthritis patients enrolled in a commercial health plan.

    PubMed

    Chastek, Benjamin; Fox, Kathleen M; Watson, Crystal; Gandra, Shravanthi R

    2012-08-01

    Treatment patterns, including persistence, gaps in therapy, switching, and discontinuation, were examined in patients with psoriatic arthritis (PsA) who received the tumor necrosis factor (TNF)-blockers etanercept or adalimumab. This retrospective study utilized administrative claims data from a United States commercial health plan. Adults (age 18-64 years) with PsA who started therapy with etanercept or adalimumab as index therapy between January 1, 2006 and December 31, 2008 were included in the analysis. Patients were continuously enrolled in the health plan for at least 6 months before and at least 12 months after the start of index therapy. Initial TNF-blocker dose and rates of therapy persistence (continuous use of index medication without a gap of at least 60 days), therapy gaps, and discontinuation (gap in therapy of at least 60 days) were estimated. Those who discontinued were further classified as: (1) discontinued all biologic therapy, (2) restarted index medication, (3) switched to another biologic therapy, or (4) other. A total of 346 patients with PsA (202 etanercept, 144 adalimumab) were eligible. Most (90.6% etanercept; 88.9% adalimumab) started index therapy at the labeled dose. Persistence with index therapy for 12 months was observed in 50% of patients on etanercept and 45% of patients on adalimumab (P = 0.37). Patients on etanercept had a longer duration of persistence (434 vs. 353 days; P = 0.02), more pauses of at least 7 days (4.7 vs. 3.5; P = 0.004), and a longer mean pause length (48.6 vs. 29.3 days; P = 0.01) than patients on adalimumab. Of patients who discontinued (24.8% etanercept; 35.1% adalimumab), 46.4% and 41.5% restarted etanercept and adalimumab, respectively; 24.8% and 35.1% discontinued all TNF-blockers; 20.0% and 19.2% switched to another biologic; and 8.8% and 4.3% had other therapy changes. Approximately half of PsA patients were persistent on their index TNF-blocker for 12 months. Pauses in therapy and therapy discontinuation were common, but more than 40% of patients restarted their index TNF-blocker after discontinuation.

  9. CECE: Expanding the Envelope of Deep Throttling Technology in Liquid Oxygen/Liquid Hydrogen Rocket Engines for NASA Exploration Missions

    NASA Technical Reports Server (NTRS)

    Giuliano, Victor J.; Leonard, Timothy G.; Lyda, Randy T.; Kim, Tony S.

    2010-01-01

    As one of the first technology development programs awarded by NASA under the Vision for Space Exploration, the Pratt & Whitney Rocketdyne (PWR) Deep Throttling, Common Extensible Cryogenic Engine (CECE) program was selected by NASA in November 2004 to begin technology development and demonstration toward a deep throttling, cryogenic engine supporting ongoing trade studies for NASA s Lunar Lander descent stage. The CECE program leverages the maturity and previous investment of a flight-proven hydrogen/oxygen expander cycle engine, the PWR RL10, to develop and demonstrate an unprecedented combination of reliability, safety, durability, throttlability, and restart capabilities in high-energy, cryogenic, in-space propulsion. The testbed selected for the deep throttling demonstration phases of this program was a minimally modified RL10 engine, allowing for maximum current production engine commonality and extensibility with minimum program cost. Four series of demonstrator engine tests have been successfully completed between April 2006 and April 2010, accumulating 7,436 seconds of hot fire time over 47 separate tests. While the first two test series explored low power combustion (chug) and system instabilities, the third test series investigated and was ultimately successful in demonstrating several mitigating technologies for these instabilities and achieved a stable throttling ratio of 13:1. The fourth test series significantly expanded the engine s operability envelope by successfully demonstrating a closed-loop control system and extensive transient modeling to enable lower power engine starting, faster throttle ramp rates, and mission-specific ignition testing. The final hot fire test demonstrated a chug-free, minimum power level of 5.9%, corresponding to an overall 17.6:1 throttling ratio achieved. In total, these tests have provided an early technology demonstration of an enabling cryogenic propulsion concept with invaluable system-level technology data acquisition toward design and development risk mitigation for future lander descent main engines.

  10. Terminal-shock and restart control of a Mach 2.5, axisymmetric, mixed compression inlet with 40 percent internal contraction. [wind tunnel tests

    NASA Technical Reports Server (NTRS)

    Baumbick, R. J.

    1974-01-01

    Results of experimental tests conducted on a supersonic, mixed-compression, axisymmetric inlet are presented. The inlet is designed for operation at Mach 2.5 with a turbofan engine (TF-30). The inlet was coupled to either a choked orifice plate or a long duct which had a variable-area choked exit plug. Closed-loop frequency responses of selected diffuser static pressures used in the terminal-shock control system are presented. Results are shown for Mach 2.5 conditions with the inlet coupled to either the choked orifice plate or the long duct. Inlet unstart-restart traces are also presented. High-response inlet bypass doors were used to generate an internal disturbance and also to achieve terminal-shock control.

  11. Documentation of a restart option for the U.S. Geological Survey coupled Groundwater and Surface-Water Flow (GSFLOW) model

    USGS Publications Warehouse

    Regan, R. Steve; Niswonger, Richard G.; Markstrom, Steven L.; Barlow, Paul M.

    2015-10-02

    The spin-up simulation should be run for a sufficient length of time necessary to establish antecedent conditions throughout a model domain. Each GSFLOW application can require different lengths of time to account for the hydrologic stresses to propagate through a coupled groundwater and surface-water system. Typically, groundwater hydrologic processes require many years to come into equilibrium with dynamic climate and other forcing (or stress) data, such as precipitation and well pumping, whereas runoff-dominated surface-water processes respond relatively quickly. Use of a spin-up simulation can substantially reduce execution-time requirements for applications where the time period of interest is small compared to the time for hydrologic memory; thus, use of the restart option can be an efficient strategy for forecast and calibration simulations that require multiple simulations starting from the same day.

  12. A simple strategy for varying the restart parameter in GMRES(m)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baker, A H; Jessup, E R; Kolev, T V

    2007-10-02

    When solving a system of linear equations with the restarted GMRES method, a fixed restart parameter is typically chosen. We present numerical experiments that demonstrate the beneficial effects of changing the value of the restart parameter in each restart cycle on the total time to solution. We propose a simple strategy for varying the restart parameter and provide some heuristic explanations for its effectiveness based on analysis of the symmetric case.

  13. General Electromagnetic Model for the Analysis of Complex Systems (GEMACS) Engineering Manual (Version 3). Volume 3.

    DTIC Science & Technology

    1983-09-01

    processor. How- ever, upon completion of the restart initialization, additional commands may be added or original commands deleted with normal input...written IOSI Scratch logical unit designator IOS1SV Saved value of lOS1 IOS2 Scratch logical unit designator IR Index pointer to upper triangular matrix

  14. Saturn Apollo Program

    NASA Image and Video Library

    1966-07-01

    AS-203, the third Saturn IB launch vehicle developed by the Marshall Space Flight Center, lifts off from Cape Canaveral, Florida , July 5, 1966. Primary mission objectives included evaluation of the S-IVB stage's hydrogen venting and engine restart capabilities in an orbital environment. In all, nine Saturn IB flights were made, ending with the Apollo-Soyuz Test Project (ASTP) in July 1975.

  15. Guidance system operations plan for manned CM earth orbital missions using program Skylark 1. Section 2: Data links

    NASA Technical Reports Server (NTRS)

    Hamilton, M. H.

    1972-01-01

    A computer program to define the digital uplink and downlink for use in manned command module orbital missions is presented. The subjects discussed are: (1) digital uplink to command module, (2) CMC digital downlink, (3) downlist formats, (4) description of telemetered qualities, (5) flagbits, and (6) effects of Fresh Start (V36) and Hardware Restart on flagword and channel bits.

  16. Introducing the LHC in the classroom: an overview of education resources available

    NASA Astrophysics Data System (ADS)

    Wiener, Gerfried J.; Woithe, Julia; Brown, Alexander; Jende, Konrad

    2016-05-01

    In the context of the recent re-start of CERN’s Large Hadron Collider (LHC) and the challenge presented by unidentified falling objects (UFOs), we seek to facilitate the introduction of high energy physics in the classroom. Therefore, this paper provides an overview of the LHC and its operation, highlighting existing education resources, and linking principal components of the LHC to topics in physics curricula.

  17. The use of phenological data to calculate chilling units in Olea europaea L. in relation to the onset of reproduction

    NASA Astrophysics Data System (ADS)

    Orlandi, F.; Fornaciari, M.; Romano, B.

    2002-02-01

    The aim of this study was to develop a practical method to evaluate the effective relationship between the amount of winter chilling and the response expressed as the spring reproductive re-starting dates in the olive ( Olea europaea L.). Two olive cultivars growing in a special olive orchard in Umbria (central Italy) were studied over a 3-year period (1998-2000): the cultivar Ascolana, typical of central Italy, and the cultivar Giarraffa, typical of southern Italy. The spring reproductive re-starts were assessed using data from detailed phenological observations made on 60 trees of each cultivar in an effort to establish the exact date of reproductive bud swelling. The chilling phenomenon was evaluated by using 341 functions derived from a formula developed by researchers at Utah State University to calculate chilling units. The mathematical functions are defined, and show the very close relationship between the amount of winter chilling and the spring reproductive response in the two cultivars in the orchard studied. The results can be used to define the relationship between local climate and plant development, and the mathematical approach can be used to draw maps that can show the suitability of different cultivars on the basis of local climatic conditions.

  18. US/CIS integrated NTRE

    NASA Astrophysics Data System (ADS)

    Bulman, M. J.; Culver, D. W.; McIlwain, M. C.; Rochow, Richard; D'Yakov, E. K.; Smetannikov, V. P.

    1993-06-01

    The paper describes the Nuclear Thermal Energy (NTRE) engine, developed by taking advantage of mature fuel technology developed in the former Soviet Union, thus shortening the development schedule of this engine for moon and Mars explorations. The near-term NTRE engine has a number of features that provide safety, mission performance, cost, and risk benefits. These include: (1) high-temperature long-life CIS fuel, (2) high-pressure recuperated expander cycle, (3) assured restart, (4) long-life cooled nozzle with thin inner wall, (5) long-life turbopumps, (6) heat radiation and electrical power generation, and (7) component integration synergy. Diagrams of the reactor core, the recuperated bottoming cycle flow schematic, and the recuperated bottoming cycle engine schematic are presented.

  19. TRW - Lunar Descent Engine. Chapter 6, Appendix H

    NASA Technical Reports Server (NTRS)

    Elverum, Gerard W.

    2009-01-01

    As we went through the program, what we determined, and what we all agreed on, was that the thrust coefficient (Cf) of the nozzle, after you get past a certain point, is really an engineering parameter. It s not a fundamental parameter that is going to be highly variable. Once we knew what the contour of the nozzle was, and once we knew what its characteristic was out to 2:1, we could calculate what the 48:1 thrust coefficient was going to be. In every case that we made a test, the calculation was precise. We weren't looking for a problem out at 48:1. Once we crushed the nozzle and said, "Yeah, we can land on the boulder," and once we had the thermal profile of that columbium nozzle, we did not require a lot of effort there. The real characterization was done in throttling over the 10:1 with the injector and controlling the mixture ratio on that - the whole head-end assembly - out to 2:1. I think everybody at NASA and Grumman agreed that flying like you test is great, particularly if you are using an aircraft engine. But, in this case, the thrust coefficient of the nozzle was not an issue. We had the tandem configuration of the service module, the command module, and the LEM sitting out there, and we were to fire the LEM. On Apollo 5, we were firing the LEM to show how it would work. There was a problem. I can t remember where the problem was, but something caused a problem before that engine had finished its burn. It was not in the engine, but there was some other problem, and NASA made a controlled shutdown. Then, they came to us and asked, "Hey, we re up there. We want to finish this test program. Is it okay if we restart that engine again in space with this tandem configuration?" We said, "As long as it has been more than forty minutes since you shut down, our analysis says that you will be okay in terms of the thermal characteristics of the inside of that chamber." They restarted it and pushed that system around in orbit on Apollo 5. It turned out, that when it came to Apollo 13, we went back into the record, and said, "Hey, we have pushed this system around up there on Apollo 5, and we have also restarted this tandem configuration." The requirements on Apollo 13 were to put it back into play. The spacecraft was out of free return to the earth at the time of the accident. It would not have come back. NASA said, "Okay, we ll use the descent engine to put the spacecraft in a free trajectory; it will go around the moon and be on free trajectory back to Earth." Then, as it came around the far side of the moon, the guys found out that they had an oxygen problem. As you remember, things were getting pretty bad in there. They said, "We ve got to get it back as fast as we can. Is it okay if we re-fire the engine? Now, we re in a free trajectory, so we want to put as much delta-v (or change in velocity) in as we can. Can we re-fire right now?" We said, "Yes, the data says it has been this period of time." We could re-fire the engine, run the rest of the duty cycle up as far as we needed while preserving enough fluids to make the final correction as the spacecraft got near Earth, and restart the engine. It was pretty fortuitous that we could give them those answers.

  20. Interrupting an Imminent Body Current Fault and Restoring Full Power in Milliseconds on a DIII-D National Fusion Facility Gyrotron

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ponce, Dan; Brambila, Rigo E.; Cengher, Mirela

    The ECH Group at DIII-D has installed in-house engineered, FPGA-based, high voltage reference waveform generators on its gyrotron control systems to enhance the capabilities of the systems and replace obsolete equipment. The new hardware, named D-Wavegen, outputs 16-bit signals every microsecond and can respond to events and anomalies in real-time. These generators have been reliably pausing gyrotron rf output during periods of DIII-D plasma density that exceed the fault density trip level and restarting the rf output if the density falls below the trip level. While tightly monitoring gyrotron body current and internal pressure, D-Wavegen has also been reliably restarting,more » in a little over 10ms, gyrotrons that spontaneously ceased rf generation.« less

  1. Interrupting an Imminent Body Current Fault and Restoring Full Power in Milliseconds on a DIII-D National Fusion Facility Gyrotron

    DOE PAGES

    Ponce, Dan; Brambila, Rigo E.; Cengher, Mirela; ...

    2017-10-19

    The ECH Group at DIII-D has installed in-house engineered, FPGA-based, high voltage reference waveform generators on its gyrotron control systems to enhance the capabilities of the systems and replace obsolete equipment. The new hardware, named D-Wavegen, outputs 16-bit signals every microsecond and can respond to events and anomalies in real-time. These generators have been reliably pausing gyrotron rf output during periods of DIII-D plasma density that exceed the fault density trip level and restarting the rf output if the density falls below the trip level. While tightly monitoring gyrotron body current and internal pressure, D-Wavegen has also been reliably restarting,more » in a little over 10ms, gyrotrons that spontaneously ceased rf generation.« less

  2. Fluctuation Flooding Method (FFM) for accelerating conformational transitions of proteins.

    PubMed

    Harada, Ryuhei; Takano, Yu; Shigeta, Yasuteru

    2014-03-28

    A powerful conformational sampling method for accelerating structural transitions of proteins, "Fluctuation Flooding Method (FFM)," is proposed. In FFM, cycles of the following steps enhance the transitions: (i) extractions of largely fluctuating snapshots along anisotropic modes obtained from trajectories of multiple independent molecular dynamics (MD) simulations and (ii) conformational re-sampling of the snapshots via re-generations of initial velocities when re-starting MD simulations. In an application to bacteriophage T4 lysozyme, FFM successfully accelerated the open-closed transition with the 6 ns simulation starting solely from the open state, although the 1-μs canonical MD simulation failed to sample such a rare event.

  3. Fluctuation Flooding Method (FFM) for accelerating conformational transitions of proteins

    NASA Astrophysics Data System (ADS)

    Harada, Ryuhei; Takano, Yu; Shigeta, Yasuteru

    2014-03-01

    A powerful conformational sampling method for accelerating structural transitions of proteins, "Fluctuation Flooding Method (FFM)," is proposed. In FFM, cycles of the following steps enhance the transitions: (i) extractions of largely fluctuating snapshots along anisotropic modes obtained from trajectories of multiple independent molecular dynamics (MD) simulations and (ii) conformational re-sampling of the snapshots via re-generations of initial velocities when re-starting MD simulations. In an application to bacteriophage T4 lysozyme, FFM successfully accelerated the open-closed transition with the 6 ns simulation starting solely from the open state, although the 1-μs canonical MD simulation failed to sample such a rare event.

  4. Pervasive Restart In MOOSE-based Applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Derek Gaston; Cody Permann; David Andrs

    Multiphysics applications are inherently complicated. Solving for multiple, interacting physical phenomena involves the solution of multiple equations, and each equation has its own data dependencies. Feeding the correct data to these equations at exactly the right time requires extensive effort in software design. In an ideal world, multiphysics applications always run to completion and produce correct answers. Unfortunately, in reality, there can be many reasons why a simulation might fail: power outage, system failure, exceeding a runtime allotment on a supercomputer, failure of the solver to converge, etc. A failure after many hours spent computing can be a significant setbackmore » for a project. Therefore, the ability to “continue” a solve from the point of failure, rather than starting again from scratch, is an essential component of any high-quality simulation tool. This process of “continuation” is commonly termed “restart” in the computational community. While the concept of restarting an application sounds ideal, the aforementioned complexities and data dependencies present in multiphysics applications make its implementation decidedly non-trivial. A running multiphysics calculation accumulates an enormous amount of “state”: current time, solution history, material properties, status of mechanical contact, etc. This “state” data comes in many different forms, including scalar, tensor, vector, and arbitrary, application-specific data types. To be able to restart an application, you must be able to both store and retrieve this data, effectively recreating the state of the application before the failure. When utilizing the Multiphysics Object Oriented Simulation Environment (MOOSE) framework developed at Idaho National Laboratory, this state data is stored both internally within the framework itself (such as solution vectors and the current time) and within the applications that use the framework. In order to implement restart in MOOSE-based applications, the total state of the system (both within the framework and without) must be stored and retrieved. To this end, the MOOSE team has implemented a “pervasive” restart capability which allows any object within MOOSE (or within a MOOSE-based application) to be declared as “state” data, and handles the storage and retrieval of said data.« less

  5. Development of a Stiffness-Based Chemistry Load Balancing Scheme, and Optimization of Input/Output and Communication, to Enable Massively Parallel High-Fidelity Internal Combustion Engine Simulations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kodavasal, Janardhan; Harms, Kevin; Srivastava, Priyesh

    A closed-cycle gasoline compression ignition engine simulation near top dead center (TDC) was used to profile the performance of a parallel commercial engine computational fluid dynamics code, as it was scaled on up to 4096 cores of an IBM Blue Gene/Q supercomputer. The test case has 9 million cells near TDC, with a fixed mesh size of 0.15 mm, and was run on configurations ranging from 128 to 4096 cores. Profiling was done for a small duration of 0.11 crank angle degrees near TDC during ignition. Optimization of input/output performance resulted in a significant speedup in reading restart files, andmore » in an over 100-times speedup in writing restart files and files for post-processing. Improvements to communication resulted in a 1400-times speedup in the mesh load balancing operation during initialization, on 4096 cores. An improved, “stiffness-based” algorithm for load balancing chemical kinetics calculations was developed, which results in an over 3-times faster run-time near ignition on 4096 cores relative to the original load balancing scheme. With this improvement to load balancing, the code achieves over 78% scaling efficiency on 2048 cores, and over 65% scaling efficiency on 4096 cores, relative to 256 cores.« less

  6. Vapor ingestion in Centaur liquid-hydrogen tank

    NASA Technical Reports Server (NTRS)

    Symons, E. P.

    1977-01-01

    Vapor ingestion phenomena were investigated using scale models of the Centaur liquid hydrogen tank to determine the height of the free surface of the liquid when vapor is intially ingested into the tank outlet. Data are compared with an analysin and, is general the agreement is very good. Predictions are presented for minimum liquid levels required in the Centaur liquid hydrogen tank in order to prevent vapor ingestion when restarting the engines in space and the quantities of liquid remaining in the tank at vapor ingestion during main engine firing.

  7. Saturn Apollo Program

    NASA Image and Video Library

    1967-01-01

    This is a view of the Saturn V S-IVB (third) stage for the AS-209 (Apollo-Soyuz test project backup vehicle) on a transporter in the right foreground, and the S-IVB stage for AS-504 (Apollo 9 mission) being installed in the Beta Test Stand 1 at the SACTO facility in California. After the S-II (second) stage dropped away, the S-IVB (third) stage ignited and burned for about two minutes to place itself and the Apollo spacecraft into the desired Earth orbit. At the proper time during this Earth parking orbit, the S-IVB stage was re-ignited to speed the Apollo spacecraft to escape velocity and inject it and the astronauts into a moon trajectory. Developed and manufactured by the Douglas Aircraft Company in California, the S-IVB stage measures about 21.5 feet in diameter, about 58 feet in length, and is powered by a single 200,000-pound-thrust J-2 engine with a re-start capability. The S-IVB stage was also used on the second stage of the Saturn IB launch vehicle.

  8. A technique for accelerating the convergence of restarted GMRES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baker, A H; Jessup, E R; Manteuffel, T

    2004-03-09

    We have observed that the residual vectors at the end of each restart cycle of restarted GMRES often alternate direction in a cyclic fashion, thereby slowing convergence. We present a new technique for accelerating the convergence of restarted GMRES by disrupting this alternating pattern. The new algorithm resembles a full conjugate gradient method with polynomial preconditioning, and its implementation requires minimal changes to the standard restarted GMRES algorithm.

  9. Near Earth Asteroid Human Mission Possibilities Using Nuclear Thermal Rocket (NTR) Propulsion

    NASA Technical Reports Server (NTRS)

    Borowski, Stanley; McCurdy, David R.; Packard, Thomas W.

    2012-01-01

    The NTR is a proven technology that generates high thrust and has a specific impulse (Isp (is) approximately 900 s) twice that of today's best chemical rockets. During the Rover and NERVA (Nuclear Engine for Rocket Vehicle Applications) programs, twenty rocket reactors were designed, built and ground tested. These tests demonstrated: (1) a wide range of thrust; (2) high temperature carbide-based nuclear fuel; (3) sustained engine operation; (4) accumulated lifetime; and (5) restart capability - all the requirements needed for a human mission to Mars. Ceramic metal fuel was also evaluated as a backup option. In NASA's recent Mars Design reference Architecture (DRA) 5.0 study, the NTR was selected as the preferred propulsion option because of its proven technology, higher performance, lower launch mass, versatile vehicle design, simple assembly, and growth potential. In contrast to other advanced propulsion options, NTP requires no large technology scale-ups. In fact, the smallest engine tested during the Rover program - the 25 klbf 'Pewee' engine is sufficient for a human Mars mission when used in a clustered engine configuration. The 'Copernicus crewed NTR Mars transfer vehicle design developed for DRA 5.0 has significant capability that can enable reusable '1-year' round trip human missions to candidate near Earth asteroids (NEAs) like 1991 JW in 2027, or 2000 SG344 and Apophis in 2028. A robotic precursor mission to 2000 SG344 in late 2023 could provide an attractive Flight Technology Demonstration of a small NTR engine that is scalable to the 25 klbf-class engine used for human missions 5 years later. In addition to the detailed scientific data gathered from on-site inspection, human NEA missions would also provide a valuable 'check out' function for key elements of the NTR transfer vehicle (its propulsion module, TransHab and life support systems, etc.) in a 'deep space' environment prior to undertaking the longer duration Mars orbital and landing missions that would follow. The initial mass in low Earth orbit required for a mission to Apophis is approximately 323 t consisting of the NTR propulsion module ((is) approximately 138 t), the integrated saddle truss and LH2 drop tank assembly ((is) approximately 123 t), and the 6-crew payload element ((is) approximately 62 t). The later includes a multi-mission Space Excursion Vehicle (MMSEV) used for close-up examination and sample gathering. The total burn time and required restarts on the three 25 klbf 'Pewee-class' engines operating at Isp (is) approximately 906 s, are approximately 76.2 minutes and 4, respectively, well below the 2 hours and 27 restarts demonstrated on the NERVA eXperimental Engine, the NRX-XE. The paper examines the benefits, requirements and characteristics of using NTP for the above NEA missions. The impacts on vehicle design of HLV payload volume and lift capability, crew size, and reusability are also quantified.

  10. Testing to Transition the J-2X from Paper to Hardware

    NASA Technical Reports Server (NTRS)

    Byrd, Tom

    2010-01-01

    The J-2X Upper Stage Engine (USE) will be the first new human-rated upper stage engine since the Apollo program of the 1960s. It is designed to carry the Ares I and Ares V into orbit and send the Ares V to the Moon as part of NASA's Constellation Program. This paper will provide an overview of progress on the design, testing, and manufacturing of this new engine in 2009 and 2010. The J-2X embodies the program goals of basing the design on proven technology and experience and seeking commonality between the Ares vehicles as a way to minimize risk, shorten development times, and live within current budget constraints. It is based on the proven J-2 engine used on the Saturn IB and Saturn V launch vehicles. The prime contractor for the J-2X is Pratt & Whitney Rocketdyne (PWR), which is under a design, development, test, and engineering (DDT&E) contract covering the period from June 2006 through September 2014. For Ares I, the J-2X will provide engine start at approximately 190,000 feet, operate roughly 500 seconds, and shut down. For Ares V, the J-2X will start at roughly 190,000 feet to place the Earth departure stage (EDS) in orbit, shut down and loiter for up to five days, re-start on command and operate for roughly 300 seconds at its secondary power level to perform trans lunar injection (TLI), followed by final engine shutdown. The J-2X development effort focuses on four key areas: early risk mitigation, design risk mitigation, component and subassembly testing, and engine system testing. Following that plan, the J-2X successfully completed its critical design review (CDR) in 2008, and it has made significant progress in 2009 and 2010 in moving from the drawing board to the machine shop and test stand. Post-CDR manufacturing is well under way, including PWR in-house and vendor hardware. In addition, a wide range of component and sub-component tests have been completed, and more component tests are planned. Testing includes heritage powerpack, turbopump inducer water flow, turbine air flow, turbopump seal testing, main injector and gas generator, injector testing, augmented spark igniter testing, nozzle side loads cold flow testing, nozzle extension film cooling flow testing, control system testing with hardware in the loop, and nozzle extension emissivity coating tests. In parallel with hardware manufacturing, work is progressing on the new A-3 test stand to support full duration altitude testing. The Stennis A-2 test stand is scheduled to be turned over to the Constellation Program in September 2010 to be modified for J-2X testing also. As the structural steel was rising on the A-3 stand, work was under way in the nearby E complex on the chemical steam generator and subscale diffuser concepts to be used to evacuate the A-3 test cell and simulate altitude conditions.

  11. Attitude Sensor and Gyro Calibration for Messenger

    NASA Technical Reports Server (NTRS)

    O'Shaughnessy, Daniel; Pittelkau, Mark E.

    2007-01-01

    The Redundant Inertial Measurement Unit Attitude Determination/Calibration (RADICAL(TM)) filter was used to estimate star tracker and gyro calibration parameters using MESSENGER telemetry data from three calibration events. We present an overview of the MESSENGER attitude sensors and their configuration is given, the calibration maneuvers are described, the results are compared with previous calibrations, and variations and trends in the estimated calibration parameters are examined. The warm restart and covariance bump features of the RADICAL(TM) filter were used to estimate calibration parameters from two disjoint telemetry streams. Results show that the calibration parameters converge faster with much less transient variation during convergence than when the filter is cold-started at the start of each telemetry stream.

  12. Erythema multiforme associated with gemfibrozil monotherapy.

    PubMed

    Yaçsar, Hamiyet Yilmaz; Ertuğrul, Ozden; Deniz, Coçskun

    2010-01-01

    A case of erythema multiforme associated with gemfibrozil monotherapy. A 46-year-old man with hyperlipidemia was treated with 600 mg gemfibrozil twice a day. On the fifth day of treatment, skin lesions consistent with erythema multiforme appeared. With the discontinuation of the treatment and start of a topical steroid treatment, the lesions recovered after 4 weeks. After 6 months, when gemfibrozil therapy was restarted, lesions reappeared on the fourth day of therapy. Lesions recovered again following the previous treatment strategies after 4 weeks. An objective casualty assessment suggests that erythema multiforme was probably related to gemfibrozil monotherapy. Patients starting gemfibrozil therapy should be warned about the occurrence of erythema multiforme in addition to previous reported and established side effects.

  13. Restarts in Conversation and Literature.

    ERIC Educational Resources Information Center

    Person, Raymond F., Jr.

    1996-01-01

    Analyzes restarts, a common feature of conversation, in literary discourse. The term "restart" refers to the repetition of a word or words within an utterance by the same speaker. Restarts in literary discourse are of two types: (1) those produced by the characters in their "real" narrative world and (2) those produced by the narrators themselves.…

  14. Interactive, Secure Web-enabled Aircraft Engine Simulation Using XML Databinding Integration

    NASA Technical Reports Server (NTRS)

    Lin, Risheng; Afjeh, Abdollah A.

    2003-01-01

    This paper discusses the detailed design of an XML databinding framework for aircraft engine simulation. The framework provides an object interface to access and use engine data. while at the same time preserving the meaning of the original data. The Language independent representation of engine component data enables users to move around XML data using HTTP through disparate networks. The application of this framework is demonstrated via a web-based turbofan propulsion system simulation using the World Wide Web (WWW). A Java Servlet based web component architecture is used for rendering XML engine data into HTML format and dealing with input events from the user, which allows users to interact with simulation data from a web browser. The simulation data can also be saved to a local disk for archiving or to restart the simulation at a later time.

  15. Impact of video technology on efficiency of pharmacist-provided anticoagulation counseling and patient comprehension.

    PubMed

    Moore, Sarah J; Blair, Elizabeth A; Steeb, David R; Reed, Brent N; Hull, J Heyward; Rodgers, Jo Ellen

    2015-06-01

    Discharge anticoagulation counseling is important for ensuring patient comprehension and optimizing clinical outcomes. As pharmacy resources become increasingly limited, the impact of informational videos on the counseling process becomes more relevant. To evaluate differences in pharmacist time spent counseling and patient comprehension (measured by the Oral Anticoagulation Knowledge [OAK] test) between informational videos and traditional face-to-face (oral) counseling. This prospective, open, parallel-group study at an academic medical center randomized 40 individuals-17 warfarin-naïve ("New Start") and 23 with prior warfarin use ("Restart")-to receive warfarin discharge education by video or face-to-face counseling. "Teach-back" questions were used in both groups. Although overall pharmacist time was reduced in the video counseling group (P < 0.001), an interaction between prior warfarin use and counseling method (P = 0.012) suggests the difference between counseling methods was smaller in New Start participants. Following adjustment, mean total time was reduced 8.71 (95% CI = 5.15-12.26) minutes (adjusted P < 0.001) in Restart participants and 2.31 (-2.19 to 6.81) minutes (adjusted P = 0.472) in New Start participants receiving video counseling. Postcounseling OAK test scores did not differ. Age, gender, socioeconomic status, and years of education were not predictive of total time or OAK test score. Use of informational videos coupled with teach-back questions significantly reduced pharmacist time spent on anticoagulation counseling without compromising short-term patient comprehension, primarily in patients with prior warfarin use. Study results demonstrate that video technology provides an efficient method of anticoagulation counseling while achieving similar comprehension. © The Author(s) 2015.

  16. Digital integrated control of a Mach 2.5 mixed-compression supersonic inlet and an augmented mixed-flow turbofan engine

    NASA Technical Reports Server (NTRS)

    Batterton, P. G.; Arpasi, D. J.; Baumbick, R. J.

    1974-01-01

    A digitally implemented integrated inlet-engine control system was designed and tested on a mixed-compression, axisymmetric, Mach 2.5, supersonic inlet with 45 percent internal supersonic area contraction and a TF30-P-3 augmented turbofan engine. The control matched engine airflow to available inlet airflow. By monitoring inlet terminal shock position and over-board bypass door command, the control adjusted engine speed so that in steady state, the shock would be at the desired location and the overboard bypass doors would be closed. During engine-induced transients, such as augmentor light-off and cutoff, the inlet operating point was momentarily changed to a more supercritical point to minimize unstarts. The digital control also provided automatic inlet restart. A variable inlet throat bleed control, based on throat Mach number, provided additional inlet stability margin.

  17. State and prospects of solid propellant rocket development

    NASA Astrophysics Data System (ADS)

    Kukushkin, V. Kh.

    1992-07-01

    An overview is presented of aspects of solid-propellant rocket engine (SPRE) development with individual treatment given to sustainer and spacecraft SPRE technologies. The paper focuses on low-modulus fuels of composite solid propellant, requirements for adhesion stability, and enhancement of the power characteristics of solid propellants. R&D activities are described that relate to the use of SPREs with extending nozzles and to the design of ultradimensional nozzles for upper-stage engines. Other developments for the SPREs include engines with separate loading and pasty fuel applications, and progress is reported in the direction of detonation SPREs. The SPREs using pasty propellants provide good control over thrust characteristics and fuel qualities. A device is incorporated that assures fuel burning in the combustion region and reliable ignition during restarting of these engines.

  18. Emergency contraception.

    PubMed

    Conard, Lee Ann E; Gold, Melanie A

    2005-10-01

    Emergency contraception is increasing in use and has become a universal standard of care in the United States. This article reviews available forms of emergency contraception, their indications, contraindications, adverse effects and efficacy at preventing pregnancy. This article describes the mechanism of action of different forms of emergency contraception and provides recommendations on when to start or restart an ongoing method of contraceptive after emergency contraception use. Literature on the impact of the advance provision of emergency contraception on contracepting behaviors is reviewed, and behavior change counseling related to emergency contraception is described.

  19. Prototype Equipment Student Guide for ACE (Air Intercept Controller Prototype Training System).

    DTIC Science & Technology

    1981-09-01

    as your " home base", directing you to where you should be (at the Student Station CRT or the Console) and stating what you could (or should) do once...review the transmissions made in your last Practice with- out Freezes (see Subsection IV A) a take a break * re-start the instruction * answer a...the instructor select the phrase from the menu. The new collections will replace the previous collections made for the phrase. instructor Two keys on

  20. El Bunduq field ready for start-up. [United Arab Emirates

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1983-10-05

    Production is scheduled to restart on the El Bunduq field. The oil field was first brought onstream in 1975 but was shut-in during 1979 due to excessive gas production. Since then, the operator, Bunduq Co., has been developing a $330-million pressure maintenance program to contain gas production and increase oil recovery. While the current field development program is based solely on reserves in the Arab D Formation, the Bunduq Co. has confirmed an oil reservoir in the shallower Arab C Formation.

  1. Affinity-aware checkpoint restart

    DOE PAGES

    Saini, Ajay; Rezaei, Arash; Mueller, Frank; ...

    2014-12-08

    Current checkpointing techniques employed to overcome faults for HPC applications result in inferior application performance after restart from a checkpoint for a number of applications. This is due to a lack of page and core affinity awareness of the checkpoint/restart (C/R) mechanism, i.e., application tasks originally pinned to cores may be restarted on different cores, and in case of non-uniform memory architectures (NUMA), quite common today, memory pages associated with tasks on a NUMA node may be associated with a different NUMA node after restart. Here, this work contributes a novel design technique for C/R mechanisms to preserve task-to-core mapsmore » and NUMA node specific page affinities across restarts. Experimental results with BLCR, a C/R mechanism, enhanced with affinity awareness demonstrate significant performance benefits of 37%-73% for the NAS Parallel Benchmark codes and 6-12% for NAMD with negligible overheads instead of up to nearly four times longer an execution times without affinity-aware restarts on 16 cores.« less

  2. Affinity-aware checkpoint restart

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Saini, Ajay; Rezaei, Arash; Mueller, Frank

    Current checkpointing techniques employed to overcome faults for HPC applications result in inferior application performance after restart from a checkpoint for a number of applications. This is due to a lack of page and core affinity awareness of the checkpoint/restart (C/R) mechanism, i.e., application tasks originally pinned to cores may be restarted on different cores, and in case of non-uniform memory architectures (NUMA), quite common today, memory pages associated with tasks on a NUMA node may be associated with a different NUMA node after restart. Here, this work contributes a novel design technique for C/R mechanisms to preserve task-to-core mapsmore » and NUMA node specific page affinities across restarts. Experimental results with BLCR, a C/R mechanism, enhanced with affinity awareness demonstrate significant performance benefits of 37%-73% for the NAS Parallel Benchmark codes and 6-12% for NAMD with negligible overheads instead of up to nearly four times longer an execution times without affinity-aware restarts on 16 cores.« less

  3. Characterization of the Vectron PX-570 Crystal Oscillator for Use in Harsh Environments

    NASA Technical Reports Server (NTRS)

    Li, Jacob; Patterson, Richard L.; Hammoud, Ahmad

    2012-01-01

    Computing hardware, data-acquisition systems, communications systems, and many electronic control systems require well-controlled timing signals for proper and accurate operation. These signals are, in most cases, provided by circuits that employ crystal oscillators due to availability, cost, ease of operation, and accuracy. In some cases, the electronic systems are expected to survive and operate under harsh conditions that include exposure to extreme temperatures. These applications exist in terrestrial systems as well as in aerospace products. Well-logging, geothermal systems, and industrial process control are examples of ground-based applications, while distributed jet engine control in aircraft, space-based observatories (such as the James Webb Space Telescope), satellites, and lunar and planetary landers are typical environments where electronics are exposed to harsh operating conditions. To ensure these devices produce reliable results, the digital heartbeat from the oscillator must deliver a stable signal that is not affected by external temperature or other conditions. One such solution is a recently introduced commercial-off-the-shelf (COTS) oscillator, the PX-570 series from Vectron International. The oscillator was designed for high-temperature applications and as proof, the crystal oscillator was subjected to a wide suite of tests to determine its ruggedness for operation in harsh environments. The tests performed by Vectron included electrical characterization under wide range of temperature, accelerated life test/aging, shock and vibration, internal moisture analysis, ESD threshold, and latch-up testing. The parametric evaluation was performed on the oscillator's frequency, output signal rise and fall times, duty cycle, and supply current over the temperature range of -125 C to +230 C. The evaluations also determined the effects of thermal cycling and the oscillator's re-start capability at extreme hot and cold temperatures. These thermal cycling and restart tests were performed at the NASA Glenn Research Center. Overall, the crystal oscillator performed well and demonstrated very good frequency stability. This paper will discuss the test procedures and present details of the performance results.

  4. Chemical Decontamination at Browns Ferry Unit 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hartwig, Ed; Reid, Richard

    2003-09-01

    In May, 2002, the Tennessee Valley Authority's (TVA) Board of Directors approved the recovery and restart of Unit 1 at Browns Ferry Nuclear Station. As an initial step in the site characterization and restart feasibility review, a majority of the primary reactor circuit was chemically decontaminated. Close cooperation between TVA and vendor personnel resulted in project completion ahead of schedule with outstanding results. The final average decontamination factors were excellent, and the final dose rates were very low, with contact readings on most points between one and three mRem/hr. In addition to allowing TVA to do a complete and thoroughmore » job of determining the feasibility of the Unit 1 restart, the decontamination effort will greatly reduce personnel exposure during plant recovery, both whole body exposure to gamma radiation and airborne exposure during pipe replacement efforts. The implementation of lessons learned from previous decontamination work performed at Browns Ferry, as well as decontamination efforts at other plants aided greatly in the success. Specific items of note are: (1) The initial leak check of the temporary decontamination system should include ancillary systems such as the spent resin system, as well as the main circulation loop. This could save time and dose exposure if leaks are discovered before the use of such systems is required. (2) Due to the quick turnaround time from the award of contract, a vendor representative was onsite early in the project to help with engineering efforts and procedures. This aided greatly in completing preparations for the decontamination. (3) The work was performed under a single maintenance activity. This resulted in great craft and plant support. (4) The constant coverage by the site's decontamination flush directors provided timely plant support and interface. (5) The FPC system isolation and back flushing to prevent residual chemicals from being left in the FPC system should have been addressed in more detail in the pre-engineering study to prevent delays during the final system cleanup.« less

  5. Method and apparatus for operating a self-starting air heating system

    DOEpatents

    Heinrich, Charles E.

    1983-12-06

    A self-starting, fuel fired, air heating system including a fuel burner fired vapor generator, a turbine, and a condenser connected in a closed circuit such that the vapor output from the vapor generator is conducted to the turbine and then to the condenser where it is condensed for return to the vapor generator. The turbine drives an air blower which passes air over the condenser for cooling the condenser and heating the air. Also, a condensate pump is driven by the turbine. The disclosure is particularly concerned with a method and apparatus which on start-up prevents the vapor generator's vapor output from being conducted to the turbine until a predetermined pressure differential has been achieved. However, after the vapor flow is once permitted, it cannot again be prevented until after the fuel burner has been shut off and restarted.

  6. 30. Engine controls and valve gear, looking aft on main ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. Engine controls and valve gear, looking aft on main (promenade) deck level. Threaded admission valve lift rods (two at immediate left of chronometer) permit adjustment of valve timing in lower and upper admission valves of cylinder (left rod controls lower valve, right rod upper valve). Valve rods are lifted by jaw-like "wipers" during operation. Exhaust valve lift rods and wipers are located to right of chronometer. Crank at extreme right drives valve wiper shaft when engaged to end of eccentric rod, shown under "Crank Indicator" dial. Pair of handles to immediate left of admission valve rods control condenser water valves; handles to right of exhaust valve rods control feedwater flow to boilers from pumps. Gauges indicate boiler pressure (left) and condenser vacuum (right); "Crank Indicator" on wall aids engineer in keeping engine crank off "dead-center" at stop so that engine may be easily restarted. - Steamboat TICONDEROGA, Shelburne Museum Route 7, Shelburne, Chittenden County, VT

  7. Engine restart aid

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fedewa, Andrew

    A system is disclosed comprising an engine having coolant passages defined therethrough, a first coolant pump, and a first radiator. The system additionally comprises a second coolant pump, a second radiator, and a liquid-to-air heat exchanger configured to condition the temperature of intake air to the engine. The system further includes a coolant valve means. For a first configuration of the coolant valve means the first coolant pump is configured to urge coolant through the coolant passages in the engine and through the first radiator, and the second coolant pump is configured to urge coolant through the liquid-to-air heat exchangermore » and through the second radiator. For a second configuration of the coolant valve means the second coolant pump is configured to urge coolant through the coolant passages in the engine and through the liquid-to-air heat exchanger. A method for controlling the system is also disclosed.« less

  8. Extreme Temperature Operation of a 10 MHz Silicon Oscillator Type STCL1100

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad

    2008-01-01

    The performance of STMicroelectronics 10 MHz silicon oscillator was evaluated under exposure to extreme temperatures. The oscillator was characterized in terms of its output frequency stability, output signal rise and fall times, duty cycle, and supply current. The effects of thermal cycling and re-start capability at extreme low and high temperatures were also investigated. The silicon oscillator chip operated well with good stability in its output frequency over the temperature region of -50 C to +130 C, a range that by far exceeded its recommended specified boundaries of -20 C to +85 C. In addition, this chip, which is a low-cost oscillator designed for use in applications where great accuracy is not required, continued to function at cryogenic temperatures as low as - 195 C but at the expense of drop in its output frequency. The STCL1100 silicon oscillator was also able to re-start at both -195 C and +130 C, and it exhibited no change in performance due to the thermal cycling. In addition, no physical damage was observed in the packaging material due to extreme temperature exposure and thermal cycling. Therefore, it can be concluded that this device could potentially be used in space exploration missions under extreme temperature conditions in microprocessor and other applications where tight clock accuracy is not critical. In addition to the aforementioned screening evaluation, additional testing, however, is required to fully establish the reliability of these devices and to determine their suitability for long-term use.

  9. Dynamic Restarting Schemes for Eigenvalue Problems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu, Kesheng; Simon, Horst D.

    1999-03-10

    In studies of restarted Davidson method, a dynamic thick-restart scheme was found to be excellent in improving the overall effectiveness of the eigen value method. This paper extends the study of the dynamic thick-restart scheme to the Lanczos method for symmetric eigen value problems and systematically explore a range of heuristics and strategies. We conduct a series of numerical tests to determine their relative strength and weakness on a class of electronic structure calculation problems.

  10. Multivariable speed synchronisation for a parallel hybrid electric vehicle drivetrain

    NASA Astrophysics Data System (ADS)

    Alt, B.; Antritter, F.; Svaricek, F.; Schultalbers, M.

    2013-03-01

    In this article, a new drivetrain configuration of a parallel hybrid electric vehicle is considered and a novel model-based control design strategy is given. In particular, the control design covers the speed synchronisation task during a restart of the internal combustion engine. The proposed multivariable synchronisation strategy is based on feedforward and decoupled feedback controllers. The performance and the robustness properties of the closed-loop system are illustrated by nonlinear simulation results.

  11. First Passage under Restart

    NASA Astrophysics Data System (ADS)

    Pal, Arnab; Reuveni, Shlomi

    2017-01-01

    First passage under restart has recently emerged as a conceptual framework suitable for the description of a wide range of phenomena, but the endless variety of ways in which restart mechanisms and first passage processes mix and match hindered the identification of unifying principles and general truths. Hope that these exist came from a recently discovered universality displayed by processes under optimal, constant rate, restart—but extensions and generalizations proved challenging as they marry arbitrarily complex processes and restart mechanisms. To address this challenge, we develop a generic approach to first passage under restart. Key features of diffusion under restart—the ultimate poster boy for this wide and diverse class of problems—are then shown to be completely universal.

  12. Growth Restart/Recovery Lines involving the vertebral body: a rare, incidental finding and diagnostic challenge in two patients

    PubMed Central

    Sajko, Sandy; Stuber, Kent; Wessely, Michelle

    2011-01-01

    Objective To present the phenomenon of growth restart lines and create awareness of the possible differential diagnoses. Clinical Features Two case reports outlining the presentation of growth restart lines found in the vertebrae of trampolinists. Emphasis in each case is placed on correlating the patient history with radiographic findings. Intervention and Outcome In both cases a conservative chiropractic treatment plan was initiated once the differential diagnoses could be ruled out. Conclusion Although the range of etiologies of growth restart lines is extensive, these case reports illustrate the importance of a comprehensive case history when presented with the radiographic finding of growth restart lines. PMID:22131568

  13. Nonlinear Meshfree Analysis Program (NMAP) Version 1.0 (User’s Manual)

    DTIC Science & Technology

    2012-12-01

    divided by the number of time increments used in the analysis . In addition to prescribing total nodal displacements in the neutral file, users are...conditions, the user must define material properties, initial conditions, and a variety of control parameters for the NMAP analysis . These data are provided...a script file. Restart A restart function is provided in the NMAP code, where the user may restart an analysis using a set of restart files. In

  14. Conjoin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sjaardema, Gregory

    2010-08-06

    Conjoin is a code for joining sequentially in time multiple exodusII database files. It is used to create a single results or restart file from multiple results or restart files which typically arise as the result of multiple restarted analyses. The resulting output file will be the union of the input files with a status variable indicating the status of each element at the various time planes.Combining multiple exodusII files arising from a restarted analysis or combining multiple exodusII files arising from a finite element analysis with dynamic topology changes.

  15. Restarting antiplatelet therapy after spontaneous intracerebral hemorrhage: Functional outcomes.

    PubMed

    Chen, Ching-Jen; Ding, Dale; Buell, Thomas J; Testai, Fernando D; Koch, Sebastian; Woo, Daniel; Worrall, Bradford B

    2018-05-30

    To compare the functional outcomes and health-related quality of life metrics of restarting vs not restarting antiplatelet therapy (APT) in patients presenting with intracerebral hemorrhage (ICH) in the ERICH (Ethnic/Racial Variations of Intracerebral Hemorrhage) study. Adult patients aged 18 years and older who were on APT before ICH and were alive at hospital discharge were included. Patients were dichotomized based on whether or not APT was restarted after hospital discharge. The primary outcome was a modified Rankin Scale score of 0-2 at 90 days. Secondary outcomes were excellent outcome (modified Rankin Scale score 0-1), mortality, Barthel Index, and health status (EuroQol-5 dimensions [EQ-5D] and EQ-5D visual analog scale scores) at 90 days. The APT and no APT cohorts comprised 127 and 732 patients, respectively. Restarting APT was associated with lower rates of good functional outcome (36.5% vs 40.8%; p = 0.021) and lower Barthel Index scores at 90 days ( p = 0.041). The 2 cohorts were then matched in a 1:1 ratio, and the matched cohorts each comprised 107 patients. No difference in primary outcome was observed between restarting vs not restarting APT (35.5% vs 43.9%; p = 0.105). There were also no differences between the secondary outcomes of the 2 cohorts. Restarting APT in patients with ICH of mild to moderate severity after acute hospitalization is not associated with worse functional outcomes or health-related quality of life at 90 days. In patients with significant cardiovascular risk factors who experience an ICH, restarting APT remains the decision of the treating practitioner. © 2018 American Academy of Neurology.

  16. Concentrating Solar Power Systems

    NASA Astrophysics Data System (ADS)

    Pitz-Paal, R.

    2017-07-01

    Development of Concentrating Solar Power Systems has started about 40 years ago. A first commercial implementation was performed between 1985 and 1991 in California. However, a drop in gas prices caused a longer period without further deployment. It was overcome in 2007 when new incentive schemes for renewables in Spain and the US enabled a commercial restart. In 2016, almost 100 commercial CSP plants with more than 5GW are installed worldwide. This paper describes the physical background of CSP technology, its technical characteristics and concepts. Furthermore, it discusses system performances, cost structures and the expected advancement.

  17. On The Lookout: The Air Mobile Ground Security and Surveillance System (AMGSS) Has Arrived

    DTIC Science & Technology

    1995-01-01

    dimensional mobility allowed by the VTOL platform are ideally suited to this concept. If (during landing) there is loss of communications detected on the...vertical-take-off-and-landing, unmanned aircraft) with a sensor pod mounted on top as shown in figure 3. Projected weight of the mission-ready AMP...to restart the engine twice. Weight and power estimates are based on commercially available hardware, modified in some cases for the AMGSSS

  18. Field Study on the Efficacy of the New Restart Provision for Hours of Service

    DOT National Transportation Integrated Search

    2014-01-01

    The objective of this research project was to examine the efficacy of the new restart rule promulgated as partof the Hours of Service of Drivers Final Rule, published on December 27, 2011, with a compliance date of July 1, 2013. Under the new restart...

  19. Mental health effects of the Three Mile Island nuclear reactor restart.

    PubMed

    Dew, M A; Bromet, E J; Schulberg, H C; Dunn, L O; Parkinson, D K

    1987-08-01

    Controversy over potential mental health effects of the Three Mile Island Unit-1 restart led the authors to examine prospectively the pattern of psychiatric symptoms in a sample of Three Mile Island area mothers of young children. Symptom levels after restart were elevated over previous levels; a sizable subcohort of the sample reported relatively serious degrees of postrestart distress. History of diagnosable major depression and generalized anxiety following the Three Mile Island accident, plus symptoms and beliefs about personal risk prior to the restart, best predicted postrestart symptoms.

  20. Terminal shock position and restart control of a Mach 2.7, two-dimensional, twin duct mixed compression inlet

    NASA Technical Reports Server (NTRS)

    Cole, G. L.; Neiner, G. H.; Baumbick, R. J.

    1973-01-01

    Experimental results of terminal shock and restart control system tests of a two-dimensional, twin-duct mixed compression inlet are presented. High-response (110-Hz bandwidth) overboard bypass doors were used, both as the variable to control shock position and as the means of disturbing the inlet airflow. An inherent instability in inlet shock position resulted in noisy feedback signals and thus restricted the terminal shock position control performance that was achieved. Proportional-plus-integral type controllers using either throat exit static pressure or shock position sensor feedback gave adequate low-frequency control. The inlet restart control system kept the terminal shock control loop closed throughout the unstart-restart transient. The capability to restart the inlet was non limited by the inlet instability.

  1. Exploring factors associated with ART adherence and retention in care under Option B+ strategy in Malawi: A qualitative study.

    PubMed

    Gugsa, Salem; Potter, Katy; Tweya, Hannock; Phiri, Sam; Sande, Odala; Sikwese, Pascal; Chikonda, Janet; O'Malley, Gabrielle

    2017-01-01

    Although several studies have documented challenges related to inadequate adherence to antiretroviral therapy (ART) and high loss to follow-up (LTFU) among Option B+ women, there is limited understanding of why these challenges occur and how to address them. This qualitative study examines women's experiences with ART adherence and retention in care. Between July and October 2015, in-depth interviews were conducted with 39 pregnant and lactating women who initiated ART at Bwaila Hospital in Lilongwe, Malawi. Study participants included 14 in care and 25 out of care women, according to facility records. Data were analyzed using an inductive, open-coding approach to thematic analysis. Ten of the respondents (7 out of care, 3 in-care) had stopped and re-started treatment before the interview date. One of the most important factors influencing adherence and retention was the strength of women's support systems. In contrast to women in-care, most out-of-care women lacked emotional and financial support from male partners, received minimal counseling from providers at initiation, lacked designated guardians to assist with medication refills or clinic appointments, and were highly mobile. Mobility led to difficulties in accessing treatment in new settings. The most common reasons women re-started treatment following interruptions were due to providers' counseling and encouragement and the mother's desire to be healthy. Improved counseling at initiation, active follow-up counseling, women's economic empowerment interventions, promotion of peer counseling schemes and meaningful engagement of male partners can help in addressing the identified barriers and promoting sustained retention of Option B+ women.

  2. Branching Search

    NASA Astrophysics Data System (ADS)

    Eliazar, Iddo

    2017-12-01

    Search processes play key roles in various scientific fields. A widespread and effective search-process scheme, which we term Restart Search, is based on the following restart algorithm: i) set a timer and initiate a search task; ii) if the task was completed before the timer expired, then stop; iii) if the timer expired before the task was completed, then go back to the first step and restart the search process anew. In this paper a branching feature is added to the restart algorithm: at every transition from the algorithm's third step to its first step branching takes place, thus multiplying the search effort. This branching feature yields a search-process scheme which we term Branching Search. The running time of Branching Search is analyzed, closed-form results are established, and these results are compared to the coresponding running-time results of Restart Search.

  3. Logistics and Capability Implications of a Bradley Fighting Vehicle with a Fuel Cell Auxiliary Power Unit

    DTIC Science & Technology

    2003-10-13

    04ANNUAL-524 Logistics and Capability Implications of a Bradley Fighting Vehicle with a Fuel Cell Auxiliary Power Unit Joseph Conover, Harry...used or the main engines are restarted. Integration of a solid oxide fuel cell (SOFC) auxiliary power unit into a military vehicle has the...presented which show the fuel usage and capability impacts of incorporating a fuel cell APU into the electrical system of a Bradley M2A3 Diesel

  4. Monitoring the Restart of a High-Rate Wastewater Disposal Well in the Val d'Agri Oilfield (Italy)

    NASA Astrophysics Data System (ADS)

    De Gori, P.; Improta, L.; Moretti, M.; Colasanti, G.; Criscuoli, F.

    2015-12-01

    The Val d'Agri Quaternary basin in the Southern Apennine range of Italy hosts the largest inland oil field in Europe. Wastewater coming from the oil exploitation is re-injected by a high-rate disposal well into strongly fractured limestones of the hydrocarbon carbonate reservoir. Disposal activity has induced micro-seismicity since the beginning of injection in June 2006. Around 220 small magnitude events (ML < 2.3) were recorded between 2006 and 2013 by the trigger-mode monitoring local network managed by the oil company and by the National Seismic Network of Istituto Nazionale di Geofisica e Vulcanologia. The induced micro-seismicity illuminated a pre-existing high-angle fault located 1 km below the well. Since June 2006, wastewater has been re-injected with only short interruptions due acid stimulations. In January 2015 disposal activity was halted due to technical operations in the oil refinery and wastewater injection restarted after two weeks. We installed 5 short-period stations within 10 km of the disposal well to carefully monitor the re-start phase and the subsequent 3 months of disposal activity. This temporary network was complemented by stations of the National Seismic Network giving this final configuration:9 stations within 10 km of the well with the closest station 2 km apart, 13 stations within 20 km. Here we report on the preliminary analysis of the local earthquake recorded during the survey focusing on the events occurred in the injection area. The seismicity rate is compared with injection data.In spite of the dense network, we found that the rate of induced seismicity (both the number and energy of events) is very low when compared to the seismicity recorded during the first 5 years of injection activity carried out with comparable rate and pressure.

  5. Stigma associated with medication treatment for young adults with opioid use disorder: a case series.

    PubMed

    Hadland, Scott E; Park, Tae Woo; Bagley, Sarah M

    2018-05-07

    Opioid-related overdose deaths have risen sharply among young adults. Despite this increase, access to evidence-based medication for opioid agonist treatment (OAT) for youth remains low. Among older adults, barriers to OAT include the paucity of buprenorphine-waivered prescribers and low rates of prescribing among waivered physicians. We have increasingly found in our clinical practice significant stigma related to using OAT to treat addiction for young adults. In this series, we describe three cases of young adults who faced significant stigma related to their treatment. The first case is a young male with a history of significant trauma and a severe opioid use disorder. He started buprenorphine and has found a job, stayed abstinent, and began a healthy relationship. At each step in his recovery, he has faced resistance to taking medication from other treatment providers, directors of sober houses, and his parents. The second case is a young woman who presented to a substance use treatment program after a relapse. She was unable to restart buprenorphine despite our calling to ask that it be restarted. Ultimately, she left against medical advice and was stabilized as an outpatient on buprenorphine. The final case is a young woman who stopped buprenorphine after being told she was "not sober" while attending 12-step group but restarted after conversations with her clinical team. In each case, the patient has continued their medication treatment and are stable. Opioid-related deaths continue to rise among all age groups, including young adults. Stigma related to medication treatment can be a substantial barrier for many young adult patients but there are concrete steps that providers and communities can take to address this stigma.

  6. ANALYSIS OF BORON DILUTION TRANSIENTS IN PWRS.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    DIAMOND,D.J.BROMLEY,B.P.ARONSON,A.L.

    2004-02-04

    A study has been carried out with PARCS/RELAP5 to understand the consequences of hypothetical boron dilution events in pressurized water reactors. The scenarios of concern start with a small-break loss-of-coolant accident. If the event leads to boiling in the core and then the loss of natural circulation, a boron-free condensate can accumulate in the cold leg. The dilution event happens when natural circulation is re-established or a reactor coolant pump (RCP) is restarted in violation of operating procedures. This event is of particular concern in B&W reactors with a lowered-loop design and is a Generic Safety Issue for the U.S.more » Nuclear Regulatory Commission. The results of calculations with the reestablishment of natural circulation show that there is no unacceptable fuel damage. This is determined by calculating the maximum fuel pellet enthalpy, based on the three-dimensional model, and comparing it with the criterion for damage. The calculation is based on a model of a B&W reactor at beginning of the fuel cycle. If an RCP is restarted, unacceptable fuel damage may be possible in plants with sufficiently large volumes of boron-free condensate in the cold leg.« less

  7. Stability of lanthanum oxide-based H 2S sorbents in realistic fuel processor/fuel cell operation

    NASA Astrophysics Data System (ADS)

    Valsamakis, Ioannis; Si, Rui; Flytzani-Stephanopoulos, Maria

    We report that lanthana-based sulfur sorbents are an excellent choice as once-through chemical filters for the removal of trace amounts of H 2S and COS from any fuel gas at temperatures matching those of solid oxide fuel cells. We have examined sorbents based on lanthana and Pr-doped lanthana with up to 30 at.% praseodymium, having high desulfurization efficiency, as measured by their ability to remove H 2S from simulated reformate gas streams to below 50 ppbv with corresponding sulfur capacity exceeding 50 mg S g sorbent -1 at 800 °C. Intermittent sorbent operation with air-rich boiler exhaust-type gas mixtures and with frequent shutdowns and restarts is possible without formation of lanthanide oxycarbonate phases. Upon restart, desulfurization continues from where it left at the end of the previous cycle. These findings are important for practical applications of these sorbents as sulfur polishing units of fuel gases in the presence of small or large amounts of water vapor, and with the regular shutdown/start-up operation practiced in fuel processors/fuel cell systems, both stationary and mobile, and of any size/scale.

  8. Space shuttle orbital maneuvering engine platelet injector program

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A platelet-face injector for the fully reusable orbit maneuvering system OMS on the space shuttle was evaluated as a means of obtaining additional design margin and low cost. Performance, heat transfer, and combustion stability were evaluated over the anticipated range of OMS operating conditions. The effects of acoustic cavity configuration on combustion stability, including cavity depth, open area, inlet contour, and other parameters, were investigated using sea level bomb tests. Prototype injector and chamber behavior was evaluated for a variety of conditions; these tests examined the effects of film cooling, helium saturated propellants, chamber length, inlet conditions, and operating point, on performance, heat transfer and engine transient behavior. Helium bubble ingestion into both propellant circuits was investigated, as was chugging at low pressure operation, and hot and cold engine restart with and without a purge.

  9. Reasons Why Children and Adolescents With Attention-Deficit/Hyperactivity Disorder Stop and Restart Taking Medicine.

    PubMed

    Brinkman, William B; Simon, John O; Epstein, Jeffery N

    2018-04-01

    To describe the prevalence of reasons why children and adolescents stop and restart attention-deficit/hyperactivity disorder (ADHD) medicine and whether functional impairment is present after stopping medicine. We used the prospective longitudinal cohort from the Multimodal Treatment of Study of Children With ADHD. At the 12-year follow-up, when participants were a mean of 21.1 years old, 372 participants (76% male, 64% white) reported ever taking ADHD medicine. Participants reported the age when they last stopped and/or restarted ADHD medicine and also endorsed reasons for stopping and restarting. Seventy-seven percent (286 of 372) reported stopping medicine for a month or longer at some time during childhood or adolescence. Participants were a mean of 13.3 years old when they last stopped medicine. The most commonly endorsed reasons for stopping medication related to 1) medicine not needed/helping, 2) adverse effects, 3) logistical barriers of getting or taking medication, and 4) social concerns or stigma. Seventeen percent (64 of 372) reported restarting medicine after stopping for a month or longer. Commonly endorsed reasons for restarting related to medicine being needed or medicine helping; and resolution of logistical barriers to getting or taking medicine. For both stopping and restarting, the proportion endorsing some reasons differed by age range, with the overall pattern suggesting that parental involvement in decisions decreased with age. Nearly all participants had impairment at the assessment after stopping, regardless of whether medication was resumed. Different reasons for stopping and/or restarting medicine are relevant at different times for different teens. Tailored strategies may help engage adolescents as full partners in their treatment plan. Copyright © 2017 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

  10. Media Training

    ScienceCinema

    None

    2017-12-09

    With the LHC starting up soon, the world's media are again turning their attention to CERN. We're all likely to be called upon to explain what is happening at CERN to media, friends and neighbours. The seminar will be given by BBC television news journalists Liz Pike and Nadia Marchant, and will deal with the kind of questions we're likely to be confronted with through the restart period. The training is open for everybody. Make sure you arrive early enough to get a seat - there are only 200 seats in the Globe. The session will also be webcast: http://webcast.cern.ch/

  11. Fission Chain Restart Theory

    DOE PAGES

    Kim, K. S.; Nakae, L. F.; Prasad, M. K.; ...

    2017-07-31

    We present that fast nanosecond timescale neutron and gamma-ray counting can be performed with a (liquid) scintillator array. Fission chains in metal evolve over a timescale of tens of nanoseconds. If the metal is surrounded by moderator, neutrons leaking from the metal can thermalize and diffuse in the moderator. With finite probability, the diffusing neutrons can return to the metal and restart the fast fission chain. The timescale for this restart process is microseconds. A theory describing time evolving fission chains for metal surrounded by moderator, including this restart process, is presented. Finally, this theory is sufficiently simple for itmore » to be implemented for real-time analysis.« less

  12. Multi-Mission Automated Task Invocation Subsystem

    NASA Technical Reports Server (NTRS)

    Cheng, Cecilia S.; Patel, Rajesh R.; Sayfi, Elias M.; Lee, Hyun H.

    2009-01-01

    Multi-Mission Automated Task Invocation Subsystem (MATIS) is software that establishes a distributed data-processing framework for automated generation of instrument data products from a spacecraft mission. Each mission may set up a set of MATIS servers for processing its data products. MATIS embodies lessons learned in experience with prior instrument- data-product-generation software. MATIS is an event-driven workflow manager that interprets project-specific, user-defined rules for managing processes. It executes programs in response to specific events under specific conditions according to the rules. Because requirements of different missions are too diverse to be satisfied by one program, MATIS accommodates plug-in programs. MATIS is flexible in that users can control such processing parameters as how many pipelines to run and on which computing machines to run them. MATIS has a fail-safe capability. At each step, MATIS captures and retains pertinent information needed to complete the step and start the next step. In the event of a restart, this information is retrieved so that processing can be resumed appropriately. At this writing, it is planned to develop a graphical user interface (GUI) for monitoring and controlling a product generation engine in MATIS. The GUI would enable users to schedule multiple processes and manage the data products produced in the processes. Although MATIS was initially designed for instrument data product generation,

  13. Stuck fermentation: development of a synthetic stuck wine and study of a restart procedure.

    PubMed

    Maisonnave, Pierre; Sanchez, Isabelle; Moine, Virginie; Dequin, Sylvie; Galeote, Virginie

    2013-05-15

    Stuck fermentation is a major problem in winemaking, resulting in large losses in the wine industry. Specific starter yeasts are used to restart stuck fermentations in conditions determined essentially on the basis of empirical know-how. We have developed a model synthetic stuck wine and an industrial process-based procedure for restarting fermentations, for studies of the conditions required to restart stuck fermentations. We used a basic medium containing 13.5% v/v ethanol and 16 g/L fructose, pH 3.3, to test the effect of various nutrients (vitamins, amino acids, minerals, oligoelements), with the aim of developing a representative and discriminative stuck fermentation model. Cell growth appeared to be a key factor for the efficient restarting of stuck fermentations. Micronutrients, such as vitamins, also strongly affected the efficiency of the restart procedure. For the validation of this medium, we compared the performances of three wine yeast strains in the synthetic stuck fermentation and three naturally stuck wine fermentations. Strain performance was ranked similar in the synthetic medium and in the "Malbec" and "Sauvignon" natural stuck wines. However, two strains were ranked differently in the "Gros Manseng" stuck wine. Nutrient content seemed to be a crucial factor in fermentation restart conditions, generating differences between yeast strains. However, the specific sensitivity of yeast strains to the composition of the wine may also have had an effect. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. 40 CFR 60.1640 - What must I do if I plan to permanently close my municipal waste combustion unit and not restart it?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... close my municipal waste combustion unit and not restart it? 60.1640 Section 60.1640 Protection of... NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Small Municipal Waste Combustion... do if I plan to permanently close my municipal waste combustion unit and not restart it? (a) If you...

  15. 40 CFR 62.15090 - What must I do if I close my municipal waste combustion unit and then restart my municipal waste...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... waste combustion unit and then restart my municipal waste combustion unit? 62.15090 Section 62.15090... Municipal Waste Combustion Units Constructed on or Before August 30, 1999 Compliance Schedule and Increments of Progress § 62.15090 What must I do if I close my municipal waste combustion unit and then restart...

  16. 40 CFR 60.1635 - What must I do if I close my municipal waste combustion unit and then restart my municipal waste...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... waste combustion unit and then restart my municipal waste combustion unit? 60.1635 Section 60.1635... Combustion Units Constructed on or Before August 30, 1999 Model Rule-Increments of Progress § 60.1635 What must I do if I close my municipal waste combustion unit and then restart my municipal waste combustion...

  17. 40 CFR 62.15090 - What must I do if I close my municipal waste combustion unit and then restart my municipal waste...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... waste combustion unit and then restart my municipal waste combustion unit? 62.15090 Section 62.15090... Municipal Waste Combustion Units Constructed on or Before August 30, 1999 Compliance Schedule and Increments of Progress § 62.15090 What must I do if I close my municipal waste combustion unit and then restart...

  18. 40 CFR 60.1635 - What must I do if I close my municipal waste combustion unit and then restart my municipal waste...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... waste combustion unit and then restart my municipal waste combustion unit? 60.1635 Section 60.1635... Combustion Units Constructed on or Before August 30, 1999 Model Rule-Increments of Progress § 60.1635 What must I do if I close my municipal waste combustion unit and then restart my municipal waste combustion...

  19. 40 CFR 60.1640 - What must I do if I plan to permanently close my municipal waste combustion unit and not restart it?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... close my municipal waste combustion unit and not restart it? 60.1640 Section 60.1640 Protection of... NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Small Municipal Waste Combustion... do if I plan to permanently close my municipal waste combustion unit and not restart it? (a) If you...

  20. 40 CFR 60.1640 - What must I do if I plan to permanently close my municipal waste combustion unit and not restart it?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... close my municipal waste combustion unit and not restart it? 60.1640 Section 60.1640 Protection of... NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Small Municipal Waste Combustion... do if I plan to permanently close my municipal waste combustion unit and not restart it? (a) If you...

  1. 40 CFR 60.1640 - What must I do if I plan to permanently close my municipal waste combustion unit and not restart it?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... close my municipal waste combustion unit and not restart it? 60.1640 Section 60.1640 Protection of... NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Small Municipal Waste Combustion... do if I plan to permanently close my municipal waste combustion unit and not restart it? (a) If you...

  2. 40 CFR 62.15090 - What must I do if I close my municipal waste combustion unit and then restart my municipal waste...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... waste combustion unit and then restart my municipal waste combustion unit? 62.15090 Section 62.15090... Municipal Waste Combustion Units Constructed on or Before August 30, 1999 Compliance Schedule and Increments of Progress § 62.15090 What must I do if I close my municipal waste combustion unit and then restart...

  3. 40 CFR 60.1635 - What must I do if I close my municipal waste combustion unit and then restart my municipal waste...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... waste combustion unit and then restart my municipal waste combustion unit? 60.1635 Section 60.1635... Combustion Units Constructed on or Before August 30, 1999 Model Rule-Increments of Progress § 60.1635 What must I do if I close my municipal waste combustion unit and then restart my municipal waste combustion...

  4. 40 CFR 60.1640 - What must I do if I plan to permanently close my municipal waste combustion unit and not restart it?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... close my municipal waste combustion unit and not restart it? 60.1640 Section 60.1640 Protection of... NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Small Municipal Waste Combustion... do if I plan to permanently close my municipal waste combustion unit and not restart it? (a) If you...

  5. 40 CFR 60.1635 - What must I do if I close my municipal waste combustion unit and then restart my municipal waste...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... waste combustion unit and then restart my municipal waste combustion unit? 60.1635 Section 60.1635... Combustion Units Constructed on or Before August 30, 1999 Model Rule-Increments of Progress § 60.1635 What must I do if I close my municipal waste combustion unit and then restart my municipal waste combustion...

  6. 40 CFR 62.15090 - What must I do if I close my municipal waste combustion unit and then restart my municipal waste...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... waste combustion unit and then restart my municipal waste combustion unit? 62.15090 Section 62.15090... Municipal Waste Combustion Units Constructed on or Before August 30, 1999 Compliance Schedule and Increments of Progress § 62.15090 What must I do if I close my municipal waste combustion unit and then restart...

  7. 40 CFR 62.15090 - What must I do if I close my municipal waste combustion unit and then restart my municipal waste...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... waste combustion unit and then restart my municipal waste combustion unit? 62.15090 Section 62.15090... Municipal Waste Combustion Units Constructed on or Before August 30, 1999 Compliance Schedule and Increments of Progress § 62.15090 What must I do if I close my municipal waste combustion unit and then restart...

  8. 40 CFR 60.1635 - What must I do if I close my municipal waste combustion unit and then restart my municipal waste...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... waste combustion unit and then restart my municipal waste combustion unit? 60.1635 Section 60.1635... Combustion Units Constructed on or Before August 30, 1999 Model Rule-Increments of Progress § 60.1635 What must I do if I close my municipal waste combustion unit and then restart my municipal waste combustion...

  9. Altitude Testing of Large Liquid Propellant Engines

    NASA Technical Reports Server (NTRS)

    Maynard, Bryon T.; Raines, Nickey G.

    2010-01-01

    The National Aeronautics and Space Administration entered a new age on January 14, 2004 with President Bush s announcement of the creation the Vision for Space Exploration that will take mankind back to the Moon and on beyond to Mars. In January, 2006, after two years of hard, dedicated labor, engineers within NASA and its contractor workforce decided that the J2X rocket, based on the heritage of the Apollo J2 engine, would be the new engine for the NASA Constellation Ares upper stage vehicle. This engine and vehicle combination would provide assured access to the International Space Station to replace that role played by the Space Shuttle and additionally, would serve as the Earth Departure Stage, to push the Crew Excursion Vehicle out of Earth Orbit and head it on a path for rendezvous with the Moon. Test as you fly, fly as you test was chosen to be the guiding philosophy and a pre-requisite for the engine design, development, test and evaluation program. An exhaustive survey of national test facility assets proved the required capability to test the J2X engine at high altitude for long durations did not exist so therefore, a high altitude/near space environment testing capability would have to be developed. After several agency concepts the A3 High Altitude Testing Facility proposal was selected by the J2X engine program on March 2, 2007 and later confirmed by a broad panel of NASA senior leadership in May 2007. This facility is to be built at NASA s John C. Stennis Space Center located near Gulfport, Mississippi. 30 plus years of Space Shuttle Main Engine development and flight certification testing makes Stennis uniquely suited to support the Vision For Space Exploration Return to the Moon. Propellant handling infrastructure, engine assembly facilities, a trained and dedicated workforce and a broad and varied technical support base will all ensure that the A3 facility will be built on time to support the schedule needs of the J2X engine and the ultimate flight of the first Ares I vehicle. The A3 facility will be able to simulate pre-ignition altitude from sea-level to 100,000 feet and maintain it up to 650 seconds. Additionally the facility will be able to accommodate initial ignition, shutdown and then restart test profiles. A3 will produce up to 5000 lbm/sec of superheated steam utilizing a Chemical Steam generation system. Two separate inline steam ejectors will be used to produce a test cell vacuum to simulate the 100,000 ft required altitude. Operational capability will ensure that the facility can start up and shutdown without producing adverse pressure gradients across the J2X nozzle. The facility will have a modern thrust measurement system for accurate determination of engine performance. The latest advances in data acquisition and control will be incorporated to measure performance parameters during hotfire testing. Provisions are being made in the initial design of the new altitude facility to allow for testing of other, larger engines and potential upper stage launch vehicles that might require vacuum start testing of the engines. The new facility at Stennis Space Center will be complete and ready for hotfire operations in late 2010.

  10. Impact of multiple-dose versus single-dose inhaler devices on COPD patients’ persistence with long-acting β2-agonists: a dispensing database analysis

    PubMed Central

    van Boven, Job FM; van Raaij, Joost J; van der Galiën, Ruben; Postma, Maarten J; van der Molen, Thys; Dekhuijzen, PN Richard; Vegter, Stefan

    2014-01-01

    Background: With a growing availability of different devices and types of medication, additional evidence is required to assist clinicians in prescribing the optimal medication in relation to chronic obstructive pulmonary disease (COPD) patients’ persistence with long-acting β2-agonists (LABAs). Aims: To assess the impact of the type of inhaler device (multiple-dose versus single-dose inhalers) on 1-year persistence and switching patterns with LABAs. Methods: A retrospective observational cohort study was performed comparing a cohort of patients initiating multiple-dose inhalers and a cohort initiating single-dose inhalers. The study population consisted of long-acting bronchodilator naive COPD patients, initiating inhalation therapy with mono-LABAs (formoterol, indacaterol or salmeterol). Analyses were performed using pharmacy dispensing data from 1994 to 2012, obtained from the IADB.nl database. Study outcomes were 1-year persistence and switching patterns. Results were adjusted for initial prescriber, initial medication, dosing regimen and relevant comorbidities. Results: In all, 575 patients initiating LABAs were included in the final study cohort. Among them, 475 (83%) initiated a multiple-dose inhaler and 100 (17%) a single-dose inhaler. Further, 269 (47%) initiated formoterol, 9 (2%) indacaterol and 297 (52%) salmeterol. There was no significant difference in persistence between users of multiple-dose or single-dose inhalers (hazard ratio: 0.98, 95% confidence interval: 0.76–1.26, P=0.99). Over 80% re-started or switched medication. Conclusions: There seems no impact of inhaler device (multiple-dose versus single-dose inhalers) on COPD patients’ persistence with LABAs. Over 80% of patients who initially seemed to discontinue LABAs, re-started their initial medication or switched inhalers or medication within 1 year. PMID:25274453

  11. Exploring factors associated with ART adherence and retention in care under Option B+ strategy in Malawi: A qualitative study

    PubMed Central

    Potter, Katy; Tweya, Hannock; Phiri, Sam; Sande, Odala; Sikwese, Pascal; Chikonda, Janet; O’Malley, Gabrielle

    2017-01-01

    Although several studies have documented challenges related to inadequate adherence to antiretroviral therapy (ART) and high loss to follow-up (LTFU) among Option B+ women, there is limited understanding of why these challenges occur and how to address them. This qualitative study examines women’s experiences with ART adherence and retention in care. Between July and October 2015, in-depth interviews were conducted with 39 pregnant and lactating women who initiated ART at Bwaila Hospital in Lilongwe, Malawi. Study participants included 14 in care and 25 out of care women, according to facility records. Data were analyzed using an inductive, open-coding approach to thematic analysis. Ten of the respondents (7 out of care, 3 in-care) had stopped and re-started treatment before the interview date. One of the most important factors influencing adherence and retention was the strength of women’s support systems. In contrast to women in-care, most out-of-care women lacked emotional and financial support from male partners, received minimal counseling from providers at initiation, lacked designated guardians to assist with medication refills or clinic appointments, and were highly mobile. Mobility led to difficulties in accessing treatment in new settings. The most common reasons women re-started treatment following interruptions were due to providers’ counseling and encouragement and the mother’s desire to be healthy. Improved counseling at initiation, active follow-up counseling, women’s economic empowerment interventions, promotion of peer counseling schemes and meaningful engagement of male partners can help in addressing the identified barriers and promoting sustained retention of Option B+ women. PMID:28636669

  12. Gas-Generator Augmented Expander Cycle Rocket Engine

    NASA Technical Reports Server (NTRS)

    Greene, William D. (Inventor)

    2011-01-01

    An augmented expander cycle rocket engine includes first and second turbopumps for respectively pumping fuel and oxidizer. A gas-generator receives a first portion of fuel output from the first turbopump and a first portion of oxidizer output from the second turbopump to ignite and discharge heated gas. A heat exchanger close-coupled to the gas-generator receives in a first conduit the discharged heated gas, and transfers heat to an adjacent second conduit carrying fuel exiting the cooling passages of a primary combustion chamber. Heat is transferred to the fuel passing through the cooling passages. The heated fuel enters the second conduit of the heat exchanger to absorb more heat from the first conduit, and then flows to drive a turbine of one or both of the turbopumps. The arrangement prevents the turbopumps exposure to combusted gas that could freeze in the turbomachinery and cause catastrophic failure upon attempted engine restart.

  13. 40 CFR 62.15095 - What must I do if I plan to permanently close my municipal waste combustion unit and not restart it?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... close my municipal waste combustion unit and not restart it? 62.15095 Section 62.15095 Protection of... Combustion Units Constructed on or Before August 30, 1999 Compliance Schedule and Increments of Progress § 62.15095 What must I do if I plan to permanently close my municipal waste combustion unit and not restart...

  14. 40 CFR 62.15095 - What must I do if I plan to permanently close my municipal waste combustion unit and not restart it?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... close my municipal waste combustion unit and not restart it? 62.15095 Section 62.15095 Protection of... Combustion Units Constructed on or Before August 30, 1999 Compliance Schedule and Increments of Progress § 62.15095 What must I do if I plan to permanently close my municipal waste combustion unit and not restart...

  15. 40 CFR 62.15095 - What must I do if I plan to permanently close my municipal waste combustion unit and not restart it?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... close my municipal waste combustion unit and not restart it? 62.15095 Section 62.15095 Protection of... Combustion Units Constructed on or Before August 30, 1999 Compliance Schedule and Increments of Progress § 62.15095 What must I do if I plan to permanently close my municipal waste combustion unit and not restart...

  16. 40 CFR 62.15095 - What must I do if I plan to permanently close my municipal waste combustion unit and not restart it?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... close my municipal waste combustion unit and not restart it? 62.15095 Section 62.15095 Protection of... Combustion Units Constructed on or Before August 30, 1999 Compliance Schedule and Increments of Progress § 62.15095 What must I do if I plan to permanently close my municipal waste combustion unit and not restart...

  17. 40 CFR 62.15095 - What must I do if I plan to permanently close my municipal waste combustion unit and not restart it?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... close my municipal waste combustion unit and not restart it? 62.15095 Section 62.15095 Protection of... Combustion Units Constructed on or Before August 30, 1999 Compliance Schedule and Increments of Progress § 62.15095 What must I do if I plan to permanently close my municipal waste combustion unit and not restart...

  18. AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT XXVIII, I--CATERPILLAR STARTING (PONEY) ENGINE (PART II), II--UNDERSTANDING MORE ABOUT STARTING DEVICES.

    ERIC Educational Resources Information Center

    Human Engineering Inst., Cleveland, OH.

    THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATION AND MAINTENANCE OF DIESEL ENGINE STARTING ENGINES. TOPICS ARE (1) STARTING ENGINE MAGNETO (WICO), (2) MAGNETO MAINTENANCE, (3) SPARK PLUGS, (4) GENERAL DESCRIPTION (STARTING DEVICES), (5) OPERATING (STARTING DEVICES), (6) LUBRICATION (STARTING DEVICES), (7)…

  19. Large perturbation flow field analysis and simulation for supersonic inlets

    NASA Technical Reports Server (NTRS)

    Varner, M. O.; Martindale, W. R.; Phares, W. J.; Kneile, K. R.; Adams, J. C., Jr.

    1984-01-01

    An analysis technique for simulation of supersonic mixed compression inlets with large flow field perturbations is presented. The approach is based upon a quasi-one-dimensional inviscid unsteady formulation which includes engineering models of unstart/restart, bleed, bypass, and geometry effects. Numerical solution of the governing time dependent equations of motion is accomplished through a shock capturing finite difference algorithm, of which five separate approaches are evaluated. Comparison with experimental supersonic wind tunnel data is presented to verify the present approach for a wide range of transient inlet flow conditions.

  20. NICMOS Filter Wheel Test

    NASA Astrophysics Data System (ADS)

    Malhotra, Sangeeta

    2003-07-01

    This is an engineering test to verify the aliveness, functionality, operability, and electro-mechanical calibration of the NICMOS filter wheel motors and assembly after NCS restart in August 2003. This test has been designed to obviate concerns over possible deformation or breakage of the fitter wheel "soda-straw" shafts due to excess rotational drag torque and/or bending moments which may be imparted due to changes in the dewar metrology from warm-up/cool-down. This test should be executed after the NCS {and filter wheel housing} has reached and approximately equilibrated to its nominal Cycle 11 operating temperature.

  1. Multibus Avionic Architecture Design Study (MAADS).

    DTIC Science & Technology

    1983-10-01

    7.0 PASKING PROFILE N0.2 p 0.1 N 1.? N 0.N THREAT p 0.2 1.1 FUSSION N1.3 N 2.S N 1.0 TARGET Nl 1.0 1FFr HF 2.6 FUSION FL I GT CONTROL H 3.0 H 12.0 H IS...System Restart o Pilot Interf ace o Pilot Initiated Restart o Recovery Restart - Power Transient (EMP, Nuclear ) o In-Flight Reload o Normal System

  2. ESP – Data from Restarted Life Tests of Various Silicon Materials

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schneider, Jim

    2010-10-06

    Current funding has allowed the restart of testing of various silicone materials placed in Life Tests or Aging Studies from past efforts. Some of these materials have been in test since 1982, with no testing for approximately 10 years, until funding allowed the restart in FY97. Charts for the various materials at different thickness, compression, and temperature combinations illustrate trends for the load-bearing properties of the materials.

  3. Starting apparatus for internal combustion engines

    DOEpatents

    Dyches, G.M.; Dudar, A.M.

    1995-01-01

    This report is a patent description for a system to start an internal combustion engine. Remote starting and starting by hearing impaired persons are addressed. The system monitors the amount of current being drawn by the starter motor to determine when the engine is started. When the engine is started the system automatically deactivates the starter motor. Five figures are included.

  4. Development Status of the CECE Cryogenic Deep Throttling Demonstrator Engine

    NASA Technical Reports Server (NTRS)

    2008-01-01

    As one of the first technology development programs awarded by NASA under the U.S. Space Exploration Policy (USSEP), the Pratt & Whitney Rocketdyne (PWR) Deep Throttling, Common Extensible Cryogenic Engine (CECE) program was selected by NASA in November 2004 to begin technology development and demonstration toward a deep throttling, cryogenic engine supporting ongoing trade studies for NASA's Lunar Lander descent stage. The CECE program leverages the maturity and previous investment of a flight-proven hydrogen/oxygen expander cycle engine, the PWR RLI0, to develop and demonstrate an unprecedented combination of reliability, safety, durability, throttlability, and restart capabilities in a high-energy, cryogenic engine. The testbed selected for the deep throttling demonstration phases of this program was a minimally modified RL10 engine, allowing for maximum current production engine commonality and extensibility with minimum program cost. Two series of demonstrator engine tests, the first in April-May 2006 and the second in March-April 2007, have demonstrated in excess of 10:1 throttling of the hydrogen/oxygen expander cycle engine. Both test series have explored a combustion instability ("chug") environment at low throttled power levels. These tests have provided an early demonstration of an enabling cryogenic propulsion concept with invaluable system-level technology data acquisition toward design and development risk mitigation for future CECE Demonstrator engine tests.

  5. The efficacy of a restart break for recycling with optimal performance depends critically on circadian timing.

    PubMed

    Van Dongen, Hans P A; Belenky, Gregory; Vila, Bryan J

    2011-07-01

    Under simulated shift-work conditions, we investigated the efficacy of a restart break for maintaining neurobehavioral functioning across consecutive duty cycles, as a function of the circadian timing of the duty periods. As part of a 14-day experiment, subjects underwent two cycles of five simulated daytime or nighttime duty days, separated by a 34-hour restart break. Cognitive functioning and high-fidelity driving simulator performance were tested 4 times per day during the two duty cycles. Lapses on a psychomotor vigilance test (PVT) served as the primary outcome variable. Selected sleep periods were recorded polysomnographically. The experiment was conducted under standardized, controlled laboratory conditions with continuous monitoring. Twenty-seven healthy adults (13 men, 14 women; aged 22-39 years) participated in the study. Subjects were randomly assigned to a nighttime duty (experimental) condition or a daytime duty (control) condition. The efficacy of the 34-hour restart break for maintaining neurobehavioral functioning from the pre-restart duty cycle to the post-restart duty cycle was compared between these two conditions. Relative to the daytime duty condition, the nighttime duty condition was associated with reduced amounts of sleep, whereas sleep latencies were shortened and slow-wave sleep appeared to be conserved. Neurobehavioral performance measures ranging from lapses of attention on the PVT to calculated fuel consumption on the driving simulators remained optimal across time of day in the daytime duty schedule, but degraded across time of night in the nighttime duty schedule. The 34-hour restart break was efficacious for maintaining PVT performance and other objective neurobehavioral functioning profiles from one duty cycle to the next in the daytime duty condition, but not in the nighttime duty condition. Subjective sleepiness did not reliably track objective neurobehavioral deficits. The 34-hour restart break was adequate for maintaining performance in the case of optimal circadian placement of sleep and duty periods (control condition) but was inadequate (and perhaps even detrimental) for maintaining performance in a simulated nighttime duty schedule (experimental condition). Current US transportation hours-of-service regulations mandate time off duty but do not consider the circadian aspects of shift scheduling. Reinforcing a recent trend of applying sleep science to inform policymaking for duty and rest times, our findings indicate that restart provisions in hours-of-service regulations could be improved by taking the circadian timing of the duty schedules into account.

  6. Promoting Recruitment using Information Management Efficiently (PRIME): study protocol for a stepped-wedge cluster randomised controlled trial within the REstart or STop Antithrombotics Randomised Trial (RESTART).

    PubMed

    Maxwell, Amy E; Dennis, Martin; Rudd, Anthony; Weir, Christopher J; Parker, Richard A; Al-Shahi Salman, Rustam

    2017-03-01

    Research into methods to boost recruitment has been identified as the highest priority for randomised controlled trial (RCT) methodological research in the United Kingdom. Slow recruitment delays the delivery of research and inflates costs. Using electronic patient records has been shown to boost recruitment to ongoing RCTs in primary care by identifying potentially eligible participants, but this approach remains relatively unexplored in secondary care, and for stroke in particular. The REstart or STop Antithrombotics Randomised Trial (RESTART; ISRCTN71907627) is an ongoing RCT of secondary prevention after stroke due to intracerebral haemorrhage. Promoting Recruitment using Information Management Efficiently (PRIME) is a stepped-wedge cluster randomised trial of a complex intervention to help RESTART sites increase their recruitment and attain their own target numbers of participants. Seventy-two hospital sites that were located in England, Wales or Scotland and were active in RESTART in June 2015 opted into PRIME. Sites were randomly allocated (using a computer-generated block randomisation algorithm, stratified by hospital location in Scotland vs. England/Wales) to one of 12 months in which the intervention would be delivered. All sites began in the control state. The intervention was delivered by a recruitment co-ordinator via a teleconference with each site. The intervention involved discussing recruitment strategies, providing software for each site to extract from their own stroke audit data lists of patients who were potentially eligible for RESTART, and a second teleconference to review progress 6 months later. The recruitment co-ordinator was blinded to the timing of the intervention until 2 months before it was due at a site. Staff at RESTART sites were blinded to the nature and timing of the intervention. The primary outcome is the total number of patients randomised into RESTART per month per site and will be analysed in a negative binomial generalised linear mixed model. PRIME began in September 2015. The last intervention was delivered in August 2016. Six-month follow-up will be complete in February 2017. The final results of PRIME will be analysed and disseminated in 2017. The PRIME study was registered in the Northern Ireland Hub for Trials Methodology Research Studies Within a Trial (SWAT) repository (SWAT22) on 23 December 2015.

  7. Engine-start Control Strategy of P2 Parallel Hybrid Electric Vehicle

    NASA Astrophysics Data System (ADS)

    Xiangyang, Xu; Siqi, Zhao; Peng, Dong

    2017-12-01

    A smooth and fast engine-start process is important to parallel hybrid electric vehicles with an electric motor mounted in front of the transmission. However, there are some challenges during the engine-start control. Firstly, the electric motor must simultaneously provide a stable driving torque to ensure the drivability and a compensative torque to drag the engine before ignition. Secondly, engine-start time is a trade-off control objective because both fast start and smooth start have to be considered. To solve these problems, this paper first analyzed the resistance of the engine start process, and established a physic model in MATLAB/Simulink. Then a model-based coordinated control strategy among engine, motor and clutch was developed. Two basic control strategy during fast start and smooth start process were studied. Simulation results showed that the control objectives were realized by applying given control strategies, which can meet different requirement from the driver.

  8. The NASA L3 Study

    NASA Technical Reports Server (NTRS)

    Stebbins, Robin

    2016-01-01

    The Astrophysics Implementation Plan calls for a minority role in L3, planned for launch in 2034. L3 The third large mission in ESAs Cosmic Visions 2015-2025 Programme NASA and ESA have been discussing a collaboration for 2 years Gravitational Observatory Advisory Team (GOAT) ESA study evaluating and recommend scientific performance tradeoffs, detection technologies, technology development activities, data analysis capabilities, schedule and cost US representatives: Guido Mueller, Mark Kasevich, Bill Klipstein, RTS Started in October 2014, concluding with a final report in late Marchor early April 2016. ESA solicited interest from ESA Member States in November 2015 NASA is continuing technology development support. ESA is restarting technology development activities.

  9. Analysis of factors associated with hesitation to restart farming after depopulation of animals due to 2010 foot-and-mouth disease epidemic in Japan.

    PubMed

    Kadowaki, Hazumu; Kayano, Taishi; Tobinaga, Takaharu; Tsutsumi, Atsuro; Watari, Michiko; Makita, Kohei

    2016-09-01

    An outbreak of foot-and-mouth disease (FMD) occurred in Miyazaki Prefecture, Japan, in 2010. This epidemic was controlled with culling and vaccination, and resulted in the death of nearly 290,000 animals. This paper describes the factors associated with hesitation to restart farming after the epidemic. A questionnaire survey was conducted to assess the mental health of farmers one year after the end of the FMD epidemic in affected areas, and univariate and multivariable analyses were performed. Of 773 farms which had answered the question about restart farming, 55.4% (428/773) had resumed or were planning to resume operation. The farms hesitated restarting were characterized by small scale (P=0.06) and having multiple sources of income (P<0.01). Personal attributes associated with hesitation to restart were advanced age of the owner (P<0.01), with someone with bad physical conditions (P=0.04) and small family size (P<0.01). Factors related to disease control during the epidemic that were associated with hesitation to restart were vaccination of animals (P<0.01), not assisting with culling on other farms (P<0.01), and higher satisfaction with information provided by the government (P=0.02). We found that farmers hesitated to resume farming because they had a limited labor force, had an alternative business or were mentally distressed during disease control.

  10. Rad53 regulates replication fork restart after DNA damage in Saccharomyces cerevisiae

    PubMed Central

    Szyjka, Shawn J.; Aparicio, Jennifer G.; Viggiani, Christopher J.; Knott, Simon; Xu, Weihong; Tavaré, Simon; Aparicio, Oscar M.

    2008-01-01

    Replication fork stalling at a DNA lesion generates a damage signal that activates the Rad53 kinase, which plays a vital role in survival by stabilizing stalled replication forks. However, evidence that Rad53 directly modulates the activity of replication forks has been lacking, and the nature of fork stabilization has remained unclear. Recently, cells lacking the Psy2–Pph3 phosphatase were shown to be defective in dephosphorylation of Rad53 as well as replication fork restart after DNA damage, suggesting a mechanistic link between Rad53 deactivation and fork restart. To test this possibility we examined the progression of replication forks in methyl-methanesulfonate (MMS)-damaged cells, under different conditions of Rad53 activity. Hyperactivity of Rad53 in pph3Δ cells slows fork progression in MMS, whereas deactivation of Rad53, through expression of dominant-negative Rad53-KD, is sufficient to allow fork restart during recovery. Furthermore, combined deletion of PPH3 and PTC2, a second, unrelated Rad53 phosphatase, results in complete replication fork arrest and lethality in MMS, demonstrating that Rad53 deactivation is a key mechanism controlling fork restart. We propose a model for regulation of replication fork progression through damaged DNA involving a cycle of Rad53 activation and deactivation that coordinates replication restart with DNA repair. PMID:18628397

  11. Gastrointestinal Hemorrhage Related to Fluoxetine in a Patient With Stroke.

    PubMed

    Wee, Tze Chao

    2017-11-01

    We report on a patient who developed massive gastrointestinal hemorrhage related to the use of fluoxetine in combination with aspirin and clopidogrel. A 58-year-old man was admitted with a posterior circulation infarct with significant weakness in all four limbs and dysarthria. Aspirin and clopidogrel were started. Fluoxetine was started for pharmacological neurostimulation to promote motor recovery and for low mood. He developed gastrointestinal hemorrhage a week after fluoxetine was started. Fluoxetine was suspended and investigations failed to reveal the source of the bleeding. He was then restarted on fluoxetine along with dual antiplatelets, and gastrointestinal hemorrhage recurred after 1 week. He was extensively investigated for a source of gastrointestinal hemorrhage, and again no source could be identified. Eventually, fluoxetine was switched to mirtazapine with no further gastrointestinal hemorrhage. He remained on dual antiplatelets. A number of case-control and cohort studies had identified the association of gastrointestinal hemorrhage with the use of selective serotonin reuptake inhibitor (SSRI). We hope to raise awareness of this association in physical medicine and rehabilitation physicians as the use of SSRI is expected to rise.

  12. Engine management during NTRE start up

    NASA Technical Reports Server (NTRS)

    Bulman, Mel; Saltzman, Dave

    1993-01-01

    The topics are presented in viewgraph form and include the following: total engine system management critical to successful nuclear thermal rocket engine (NTRE) start up; NERVA type engine start windows; reactor power control; heterogeneous reactor cooling; propellant feed system dynamics; integrated NTRE start sequence; moderator cooling loop and efficient NTRE starting; analytical simulation and low risk engine development; accurate simulation through dynamic coupling of physical processes; and integrated NTRE and mission performance.

  13. The Efficacy of a Restart Break for Recycling with Optimal Performance Depends Critically on Circadian Timing

    PubMed Central

    Van Dongen, Hans P.A.; Belenky, Gregory; Vila, Bryan J.

    2011-01-01

    Objectives: Under simulated shift-work conditions, we investigated the efficacy of a restart break for maintaining neurobehavioral functioning across consecutive duty cycles, as a function of the circadian timing of the duty periods. Design: As part of a 14-day experiment, subjects underwent two cycles of five simulated daytime or nighttime duty days, separated by a 34-hour restart break. Cognitive functioning and high-fidelity driving simulator performance were tested 4 times per day during the two duty cycles. Lapses on a psychomotor vigilance test (PVT) served as the primary outcome variable. Selected sleep periods were recorded polysomnographically. Setting: The experiment was conducted under standardized, controlled laboratory conditions with continuous monitoring. Participants: Twenty-seven healthy adults (13 men, 14 women; aged 22–39 years) participated in the study. Interventions: Subjects were randomly assigned to a nighttime duty (experimental) condition or a daytime duty (control) condition. The efficacy of the 34-hour restart break for maintaining neurobehavioral functioning from the pre-restart duty cycle to the post-restart duty cycle was compared between these two conditions. Results: Relative to the daytime duty condition, the nighttime duty condition was associated with reduced amounts of sleep, whereas sleep latencies were shortened and slow-wave sleep appeared to be conserved. Neurobehavioral performance measures ranging from lapses of attention on the PVT to calculated fuel consumption on the driving simulators remained optimal across time of day in the daytime duty schedule, but degraded across time of night in the nighttime duty schedule. The 34-hour restart break was efficacious for maintaining PVT performance and other objective neurobehavioral functioning profiles from one duty cycle to the next in the daytime duty condition, but not in the nighttime duty condition. Subjective sleepiness did not reliably track objective neurobehavioral deficits. Conclusions: The 34-hour restart break was adequate for maintaining performance in the case of optimal circadian placement of sleep and duty periods (control condition) but was inadequate (and perhaps even detrimental) for maintaining performance in a simulated nighttime duty schedule (experimental condition). Current US transportation hours-of-service regulations mandate time off duty but do not consider the circadian aspects of shift scheduling. Reinforcing a recent trend of applying sleep science to inform policymaking for duty and rest times, our findings indicate that restart provisions in hours-of-service regulations could be improved by taking the circadian timing of the duty schedules into account. Citation: Van Dongen HPA; Belenky G; Vila BJ. The efficacy of a restart break for recycling with optimal performance depends critically on circadian timing. SLEEP 2011;34(7):917-929. PMID:21731142

  14. Hybrid: Starting

    Science.gov Websites

    : gray bar STARTING When the vehicle is started, the gasoline engine "warms up." If necessary assists the gasoline engine when additional power is needed. It also acts as a generator, converting also starts the gasoline engine instantly when needed. Main stage: See through car with battery, engine

  15. Psychosocial effects of restarting a TMI reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1990-01-01

    ORNL is studying human responses to hazardous environmental phenomena. This study attempts to understand the human behavior associated with the restart of TMI-1 Reactor after a nuclear event occurred at TMI-2.

  16. Analysis of factors associated with hesitation to restart farming after depopulation of animals due to 2010 foot-and-mouth disease epidemic in Japan

    PubMed Central

    KADOWAKI, Hazumu; KAYANO, Taishi; TOBINAGA, Takaharu; TSUTSUMI, Atsuro; WATARI, Michiko; MAKITA, Kohei

    2016-01-01

    An outbreak of foot-and-mouth disease (FMD) occurred in Miyazaki Prefecture, Japan, in 2010. This epidemic was controlled with culling and vaccination, and resulted in the death of nearly 290,000 animals. This paper describes the factors associated with hesitation to restart farming after the epidemic. A questionnaire survey was conducted to assess the mental health of farmers one year after the end of the FMD epidemic in affected areas, and univariate and multivariable analyses were performed. Of 773 farms which had answered the question about restart farming, 55.4% (428/773) had resumed or were planning to resume operation. The farms hesitated restarting were characterized by small scale (P=0.06) and having multiple sources of income (P<0.01). Personal attributes associated with hesitation to restart were advanced age of the owner (P<0.01), with someone with bad physical conditions (P=0.04) and small family size (P<0.01). Factors related to disease control during the epidemic that were associated with hesitation to restart were vaccination of animals (P<0.01), not assisting with culling on other farms (P<0.01), and higher satisfaction with information provided by the government (P=0.02). We found that farmers hesitated to resume farming because they had a limited labor force, had an alternative business or were mentally distressed during disease control. PMID:27149890

  17. 46 CFR 62.35-35 - Starting systems for internal-combustion engines.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Starting systems for internal-combustion engines. 62.35-35 Section 62.35-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE... Starting systems for internal-combustion engines. The starting systems for propulsion engines and for prime...

  18. 46 CFR 62.35-35 - Starting systems for internal-combustion engines.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Starting systems for internal-combustion engines. 62.35-35 Section 62.35-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE... Starting systems for internal-combustion engines. The starting systems for propulsion engines and for prime...

  19. 46 CFR 62.35-35 - Starting systems for internal-combustion engines.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Starting systems for internal-combustion engines. 62.35-35 Section 62.35-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE... Starting systems for internal-combustion engines. The starting systems for propulsion engines and for prime...

  20. 46 CFR 62.35-35 - Starting systems for internal-combustion engines.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Starting systems for internal-combustion engines. 62.35-35 Section 62.35-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE... Starting systems for internal-combustion engines. The starting systems for propulsion engines and for prime...

  1. 46 CFR 62.35-35 - Starting systems for internal-combustion engines.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Starting systems for internal-combustion engines. 62.35-35 Section 62.35-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE... Starting systems for internal-combustion engines. The starting systems for propulsion engines and for prime...

  2. A pressure flux-split technique for computation of inlet flow behavior

    NASA Technical Reports Server (NTRS)

    Pordal, H. S.; Khosla, P. K.; Rubin, S. G.

    1991-01-01

    A method for calculating the flow field in aircraft engine inlets is presented. The phenomena of inlet unstart and restart are investigated. Solutions of the reduced Navier-Stokes (RNS) equations are obtained with a time consistent direct sparse matrix solver that computes the transient flow field both internal and external to the inlet. Time varying shocks and time varying recirculation regions can be efficiently analyzed. The code is quite general and is suitable for the computation of flow for a wide variety of geometries and over a wide range of Mach and Reynolds numbers.

  3. Fluid behavior in microgravity environment

    NASA Technical Reports Server (NTRS)

    Hung, R. J.; Lee, C. C.; Tsao, Y. D.

    1990-01-01

    The instability of liquid and gas interface can be induced by the presence of longitudinal and lateral accelerations, vehicle vibration, and rotational fields of spacecraft in a microgravity environment. In a spacecraft design, the requirements of settled propellant are different for tank pressurization, engine restart, venting, or propellent transfer. In this paper, the dynamical behavior of liquid propellant, fluid reorientation, and propellent resettling have been carried out through the execution of a CRAY X-MP super computer to simulate fluid management in a microgravity environment. Characteristics of slosh waves excited by the restoring force field of gravity jitters have also been investigated.

  4. Mud Mountain Outlet Structure; Hydraulic Model Investigation

    DTIC Science & Technology

    1993-10-01

    of the U.S. Army Engineer District, Seattle. The investigation was stopped by the Seattle District on 15 June 1987 and restarted on 15 December 1987 ...degrees (angle) 0.01745329 radians feet 0.3048 meters 0 feet of water (39.2 F) 2,968M8 Idlopascads Inches 2.54 vsnrttmerts miles (U.S. statute) 1.609347...0 5 WASINGTO N- SE~rr4 MUD SEATTE MONFAI LOCAIONIT MAP PUYALLU 10 5 0 𔃺v5IE FigureA 1. PrjetloDto 0 MOUNTAI 2 ~ ~ ~ 7 DAMer1Inrduto 7 165 5~~V 5I S m

  5. A Job Pause Service under LAM/MPI+BLCR for Transparent Fault Tolerance

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Chao; Mueller, Frank; Engelmann, Christian

    2007-01-01

    Checkpoint/restart (C/R) has become a requirement for long-running jobs in large-scale clusters due to a meantime- to-failure (MTTF) in the order of hours. After a failure, C/R mechanisms generally require a complete restart of an MPI job from the last checkpoint. A complete restart, however, is unnecessary since all but one node are typically still alive. Furthermore, a restart may result in lengthy job requeuing even though the original job had not exceeded its time quantum. In this paper, we overcome these shortcomings. Instead of job restart, we have developed a transparent mechanism for job pause within LAM/MPI+BLCR. This mechanismmore » allows live nodes to remain active and roll back to the last checkpoint while failed nodes are dynamically replaced by spares before resuming from the last checkpoint. Our methodology includes LAM/MPI enhancements in support of scalable group communicationwith fluctuating number of nodes, reuse of network connections, transparent coordinated checkpoint scheduling and a BLCR enhancement for job pause. Experiments in a cluster with the NAS Parallel Benchmark suite show that our overhead for job pause is comparable to that of a complete job restart. A minimal overhead of 5.6% is only incurred in case migration takes place while the regular checkpoint overhead remains unchanged. Yet, our approach alleviates the need to reboot the LAM run-time environment, which accounts for considerable overhead resulting in net savings of our scheme in the experiments. Our solution further provides full transparency and automation with the additional benefit of reusing existing resources. Executing continues after failures within the scheduled job, i.e., the application staging overhead is not incurred again in contrast to a restart. Our scheme offers additional potential for savings through incremental checkpointing and proactive diskless live migration, which we are currently working on.« less

  6. SERT 2 thruster space restart, 1974

    NASA Technical Reports Server (NTRS)

    Kerslake, W. R.; Finke, R. C.

    1975-01-01

    The results of testing the flight thrusters on the SERT spacecraft during the 1974 test period are presented. The most notable result was the clearing of the high voltage short from thruster 2 and the successful stable operation of its ion beam. Test periods were limited to 70 minutes or less by earth eclipse of the spacecraft solar array and by ground station coverage limitations. Thruster 2 was restarted 26 times with an ion beam produced 21 times. The high voltage short remains in thruster 1, but the cathodes were restarted 12 times to demonstrate continued restart capability. The propellant feed systems, power processors, and spacecraft ancillary equipment were demonstrated to be functional after 4 1/2 years in space. In addition to the thruster tests, a neutralizer cathode was operated separately to demonstrate that the potential level of a spacecraft could be controlled by the neutralizer alone.

  7. Solution structure of the N-terminal domain of a replication restart primosome factor, PriC, in Escherichia coli

    PubMed Central

    Aramaki, Takahiko; Abe, Yoshito; Katayama, Tsutomu; Ueda, Tadashi

    2013-01-01

    In eubacterial organisms, the oriC-independent primosome plays an essential role in replication restart after the dissociation of the replication DNA-protein complex by DNA damage. PriC is a key protein component in the replication restart primosome. Our recent study suggested that PriC is divided into two domains: an N-terminal and a C-terminal domain. In the present study, we determined the solution structure of the N-terminal domain, whose structure and function have remained unknown until now. The revealed structure was composed of three helices and one extended loop. We also observed chemical shift changes in the heteronuclear NMR spectrum and oligomerization in the presence of ssDNA. These abilities may contribute to the PriC-ssDNA complex, which is important for the replication restart primosome. PMID:23868391

  8. Mechanisms of bacterial DNA replication restart

    PubMed Central

    Windgassen, Tricia A; Wessel, Sarah R; Bhattacharyya, Basudeb

    2018-01-01

    Abstract Multi-protein DNA replication complexes called replisomes perform the essential process of copying cellular genetic information prior to cell division. Under ideal conditions, replisomes dissociate only after the entire genome has been duplicated. However, DNA replication rarely occurs without interruptions that can dislodge replisomes from DNA. Such events produce incompletely replicated chromosomes that, if left unrepaired, prevent the segregation of full genomes to daughter cells. To mitigate this threat, cells have evolved ‘DNA replication restart’ pathways that have been best defined in bacteria. Replication restart requires recognition and remodeling of abandoned replication forks by DNA replication restart proteins followed by reloading of the replicative DNA helicase, which subsequently directs assembly of the remaining replisome subunits. This review summarizes our current understanding of the mechanisms underlying replication restart and the proteins that drive the process in Escherichia coli (PriA, PriB, PriC and DnaT). PMID:29202195

  9. A Wide Range Temperature Sensor Using SOI Technology

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Elbuluk, Malik E.; Hammoud, Ahmad

    2009-01-01

    Silicon-on-insulator (SOI) technology is becoming widely used in integrated circuit chips for its advantages over the conventional silicon counterpart. The decrease in leakage current combined with lower power consumption allows electronics to operate in a broader temperature range. This paper describes the performance of an SOIbased temperature sensor under extreme temperatures and thermal cycling. The sensor comprised of a temperature-to-frequency relaxation oscillator circuit utilizing an SOI precision timer chip. The circuit was evaluated under extreme temperature exposure and thermal cycling between -190 C and +210 C. The results indicate that the sensor performed well over the entire test temperature range and it was able to re-start at extreme temperatures.

  10. A case of gait disturbance caused by low-dose gabapentin

    PubMed Central

    Kanao-Kanda, Megumi; Kanda, Hirotsugu; Takahata, Osamu; Kunisawa, Takayuki

    2016-01-01

    Gabapentin, an anticonvulsant agent, is now often used for the treatment of neuropathic pain all over the world. It is unclear whether the combined use of gabapentin, sodium valproate, and flunitrazepam results in enhancement of the side effect, a gait disturbance. A 60-year-old man was taking oral sodium valproate for symptomatic epilepsy after a brain contusion and flunitrazepam to relieve insomnia. Oral gabapentin therapy was started for suspected neuropathic pain. Although the initial dose of oral gabapentin (200 mg) relieved the pain, the lower extremities became weak, resulting in a gait disturbance. The therapy was restarted with a halved dose, and this resolved the gait disturbance and relieved the pain. PMID:27354808

  11. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Christon, Mark A.; Bakosi, Jozsef; Lowrie, Robert B.

    Hydra-TH is a hybrid finite-element/finite-volume code built using the Hydra toolkit specifically to attack a broad class of incompressible, viscous fluid dynamics problems prevalent in the thermalhydraulics community. The purpose for this manual is provide sufficient information for an experience analyst to use Hydra-TH in an effective way. The Hydra-TH User's Manual present a brief overview of capabilities and visualization interfaces. The execution and restart models are described before turning to the detailed description of keyword input. Finally, a series of example problems are presented with sufficient data to permit the user to verify the local installation of Hydra-TH, andmore » to permit a convenient starting point for more detailed and complex analyses.« less

  12. Rover/NERVA-derived near-term nuclear propulsion

    NASA Technical Reports Server (NTRS)

    1993-01-01

    FY-92 accomplishments centered on conceptual design and analyses for 25, 50, and 75 K engines with emphasis on the 50 K engine. During the first period of performance, flow and energy balances were prepared for each of these configurations and thrust-to-weight values were estimated. A review of fuel technology and key data from the Rover/NERVA program established a baseline for proven reactor performance and areas of enhancement to meet near-term goals. Studies were performed of the criticality and temperature profiles for probable fuel and moderator loadings for the three engine sizes, with a more detailed analysis of the 50 K size. During the second period of performance, analyses of the 50 K engine continued. A chamber/nozzle contour was selected and heat transfer and fatigue analyses were performed for likely construction materials. Reactor analyses were performed to determine component radiation heating rates, reactor radiation fields, water immersion poisoning requirements, temperature limits for restartability, and a tie-tube thermal analysis. Finally, a brief assessment of key enabling technologies was made, with a view toward identifying development issues and identification of the critical path toward achieving engine qualification within 10 years.

  13. Interactive Educational Tool for Turbofan and Afterburning Turbojet Engines

    NASA Technical Reports Server (NTRS)

    Benson, Thomas J.

    1997-01-01

    A workstation-based, interactive educational computer program has been developed at the NASA Lewis Research Center to aid in the teaching and understanding of turbine engine design and analysis. This tool has recently been extended to model the performance of two-spool turbofans and afterburning turbojets. The program solves for the flow conditions through the engine by using classical one-dimensional thermodynamic analysis found in various propulsion textbooks. Either an approximately thermally perfect or calorically perfect gas can be used in the thermodynamic analysis. Students can vary the design conditions through a graphical user interface; engine performance is calculated immediately. A variety of graphical formats are used to present results, including numerical results, moving bar charts, and student-generated temperature versus entropy (Ts), pressure versus specific volume (pv), and engine performance plots. The package includes user-controlled printed output, restart capability, online help screens, and a browser that displays teacher-prepared lessons in turbomachinery. The program runs on a variety of workstations or a personal computer using the UNIX operating system and X-based graphics. It is being tested at several universities in the midwestern United States; the source and executables are available free from the author.

  14. Partial oxidation for improved cold starts in alcohol-fueled engines: Phase 2 topical report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1998-04-01

    Alcohol fuels exhibit poor cold-start performance because of their low volatility. Neat alcohol engines become difficult, if not impossible, to start at temperatures close to or below freezing. Improvements in the cold-start performance (both time to start and emissions) are essential to capture the full benefits of alcohols as an alternative transportation fuel. The objective of this project was to develop a neat alcohol partial oxidation (POX) reforming technology to improve an alcohol engine`s ability to start at low temperatures (as low as {minus}30 C) and to reduce its cold-start emissions. The project emphasis was on fuel-grade ethanol (E95) butmore » the technology can be easily extended to other alcohol fuels. Ultimately a compact, on-vehicle, ethanol POX reactor was developed as a fuel system component to produce a hydrogen-rich, fuel-gas mixture for cold starts. The POX reactor is an easily controllable combustion device that allows flexibility during engine startup even in the most extreme conditions. It is a small device that is mounted directly onto the engine intake manifold. The gaseous fuel products (or reformate) from the POX reactor exit the chamber and enter the intake manifold, either replacing or supplementing the standard ethanol fuel consumed during an engine start. The combustion of the reformate during startup can reduce engine start time and tail-pipe emissions.« less

  15. Recurrence of ICH after resumption of anticoagulation with VK antagonists: CHIRONE study.

    PubMed

    Poli, Daniela; Antonucci, Emilia; Dentali, Francesco; Erba, Nicoletta; Testa, Sophie; Tiraferri, Eros; Palareti, Gualtiero

    2014-03-25

    To evaluate the risk of recurrent intracranial hemorrhage (ICH) in patients on vitamin K antagonists (VKAs) after a first episode of ICH. The Cerebral Haemorrhage in patients Restarting Oral Anticoagulant Therapy (CHIRONE) Study collected data of patients eligible for the study from the database of 27 centers affiliated with the Italian Federation of Anticoagulation Clinics. We enrolled 267 patients (163 male, median age 73.9 years) who had received VKA anticoagulation after an ICH event. During the total period of follow-up (778 patient-years), ICH recurred in 20 patients (7.5%; rate 2.56 × 100 patient-years) at a median time of 16.5 months, and was fatal in 5 patients (25%; rate 0.4 × 100 patient-years). Male sex, hypertension, prosthetic valves, previous ischemic stroke, renal failure, cancer, and spontaneous events were associated with the risk of recurrence, though none of them in isolation reached statistical significance. More than one-third of spontaneous recurrences occurred in patients with a posttraumatic index event. Our results show that patients with a history of ICH carry a significant risk of recurrent ICH when treated with VKA anticoagulation. The risk is also present, though to a lower degree, in patients with previous posttraumatic events. All patients with a history of ICH require a careful evaluation of their thromboembolic risk to estimate the net clinical benefit of (re)starting anticoagulation with VKAs.

  16. Summary of Part 75 Administrative Processes: Table 6

    EPA Pesticide Factsheets

    Learn how to submit information for a new unit, new stack or new FGD; unit shutdown and restart, long term cold storage (LTCS), expected restart date, postponement of Appendix E testing, backup fuel used, and notice of combustion of emergency fuel.

  17. On the Convergence of an Implicitly Restarted Arnoldi Method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lehoucq, Richard B.

    We show that Sorensen's [35] implicitly restarted Arnoldi method (including its block extension) is simultaneous iteration with an implicit projection step to accelerate convergence to the invariant subspace of interest. By using the geometric convergence theory for simultaneous iteration due to Watkins and Elsner [43], we prove that an implicitly restarted Arnoldi method can achieve a super-linear rate of convergence to the dominant invariant subspace of a matrix. Moreover, we show how an IRAM computes a nested sequence of approximations for the partial Schur decomposition associated with the dominant invariant subspace of a matrix.

  18. The crystal structure of Neisseria gonorrhoeae PriB reveals mechanistic differences among bacterial DNA replication restart pathways

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dong, Jinlan; George, Nicholas P.; Duckett, Katrina L.

    2010-05-25

    Reactivation of repaired DNA replication forks is essential for complete duplication of bacterial genomes. However, not all bacteria encode homologs of the well-studied Escherichia coli DNA replication restart primosome proteins, suggesting that there might be distinct mechanistic differences among DNA replication restart pathways in diverse bacteria. Since reactivation of repaired DNA replication forks requires coordinated DNA and protein binding by DNA replication restart primosome proteins, we determined the crystal structure of Neisseria gonorrhoeae PriB at 2.7 {angstrom} resolution and investigated its ability to physically interact with DNA and PriA helicase. Comparison of the crystal structures of PriB from N. gonorrhoeaemore » and E. coli reveals a well-conserved homodimeric structure consisting of two oligosaccharide/oligonucleotide-binding (OB) folds. In spite of their overall structural similarity, there is significant species variation in the type and distribution of surface amino acid residues. This correlates with striking differences in the affinity with which each PriB homolog binds single-stranded DNA and PriA helicase. These results provide evidence that mechanisms of DNA replication restart are not identical across diverse species and that these pathways have likely become specialized to meet the needs of individual organisms.« less

  19. Initialization and Restart in Stochastic Local Search: Computing a Most Probable Explanation in Bayesian Networks

    NASA Technical Reports Server (NTRS)

    Mengshoel, Ole J.; Wilkins, David C.; Roth, Dan

    2010-01-01

    For hard computational problems, stochastic local search has proven to be a competitive approach to finding optimal or approximately optimal problem solutions. Two key research questions for stochastic local search algorithms are: Which algorithms are effective for initialization? When should the search process be restarted? In the present work we investigate these research questions in the context of approximate computation of most probable explanations (MPEs) in Bayesian networks (BNs). We introduce a novel approach, based on the Viterbi algorithm, to explanation initialization in BNs. While the Viterbi algorithm works on sequences and trees, our approach works on BNs with arbitrary topologies. We also give a novel formalization of stochastic local search, with focus on initialization and restart, using probability theory and mixture models. Experimentally, we apply our methods to the problem of MPE computation, using a stochastic local search algorithm known as Stochastic Greedy Search. By carefully optimizing both initialization and restart, we reduce the MPE search time for application BNs by several orders of magnitude compared to using uniform at random initialization without restart. On several BNs from applications, the performance of Stochastic Greedy Search is competitive with clique tree clustering, a state-of-the-art exact algorithm used for MPE computation in BNs.

  20. Depressive symptoms, lifestyle structure, and ART adherence among HIV-infected individuals: a longitudinal mediation analysis.

    PubMed

    Magidson, Jessica F; Blashill, Aaron J; Safren, Steven A; Wagner, Glenn J

    2015-01-01

    Despite the well-documented relationship between depression and antiretroviral therapy (ART) nonadherence, few studies have identified explanatory pathways through which depression affects adherence. The current study tested lifestyle structure-the degree of organization and routinization of daily activities-as a mediator of this relationship, given previous evidence of lifestyle structure being associated with both depression and ART nonadherence. HIV-infected individuals starting or re-starting ART in the California Collaborative Treatment Group 578 study (n = 199) were assessed over 48 weeks. Adherence was measured using electronic monitoring caps to determine dose timing and doses taken, and viral load was assessed. The mediating role of lifestyle structure was tested using generalized linear mixed-effects modeling and bootstrapping. Lifestyle significantly mediated the relationship between depression and both measures of ART adherence behavior. Interventions that minimize disruptions to lifestyle structure and link adherence to daily activities may be useful for individuals with depression and ART nonadherence.

  1. Multiple Restart Testing of a Stainless Steel Sodium Heat Pipe Module

    NASA Astrophysics Data System (ADS)

    Martin, James; Mireles, Omar; Reid, Robert

    2005-02-01

    A heat pipe cooled reactor is one of several candidate reactor concepts being considered for space power and propulsion systems to support future space exploration activities. Long life heat pipe modules, with concepts verified through a combination of theoretical analysis and experimental evaluations, would be necessary to establish the viability of this option. A number of stainless steel/sodium heat pipe modules have been designed and fabricated to support experimental testing of a Safe Affordable Fission Engine (SAFE) project, a 100-kWt core design pursued jointly by the Marshall Space Flight Center and the Los Alamos National Laboratory. One of the SAFE heat pipe modules was successfully subjected to over 200 restarts, examining the behavior of multiple passive freeze/thaw operations. Typical operation included a 1-hour startup to an average evaporator temperature of 1000 K followed by a 15-minute hold at temperature. Nominal maximum input power to the evaporator (measured at the power supply) during the hold period was 1.9 kW, with approximately 1.6 kW calculated as the axial power transfer to the condenser (the 300W difference was lost to environment at the evaporator surface). Between heating cycles the module was cooled to less than 325 K, returning the sodium to a frozen state in preparation for the next startup cycle.

  2. Multiple Restart Testing of a Stainless Steel Sodium Heat Pipe Module

    NASA Technical Reports Server (NTRS)

    Martin, James; Mireles, Omar; Reid, Robert

    2005-01-01

    A heat pipe cooled reactor is one of several candidate reactor cores being considered for space power and propulsion systems to support future space exploration activities. Long life heat pipe modules. with designs verified through a combination of theoretical analysis and experimental evaluations. would be necessary to establish the viability of this option. A hardware-based program was initiated to begin experimental testing of components to verify compliance of proposed designs. To this end, a number of stainless steel/sodium heat pipe modules have been designed and fabricated to support experimental testing of a Safe Affordable Fission Engine (SAFE) project, a 100-kWt core design pursued jointly by the Marshall Space Flight Center and the Los Alamos National Laboratory. One of the SAFE heat pipe modules was successfully subjected to over 200 restarts. examining the behavior of multiple passive freeze/thaw operations. Typical operation included a 1-hour startup to an average evaporator temperature of 1000 K followed by a 15 minute hold at temperature. Nominal maximum input power during the hold period was 1.9 kW. Between heating cycles the module was cooled to less than 325 K, returning the sodium to a frozen state in preparation fop the next startup cycle.

  3. Aerojet - AJ10-137 Apollo Service Module Engine. Chapter 5, Appendix G

    NASA Technical Reports Server (NTRS)

    Boyce, Clay

    2009-01-01

    The general configuration of the SPS engine was 20,000 pounds of thrust, with a chamber pressure of 100 psi and specific impulse (Isp) of 314.5. The very large nozzle had an area ratio of 62.5:1 (exit area to throat area). The propellants were nitrogen tetroxide (also known as N2O4 and nitrous oxide) and A-50. A-50 was a hydrazine family fuel. Aerojet developed it for the Titan Missile Program when they went with Titan II, to store it in the launch silos. They wanted the highest performance they could get. N2H4 was just pure hydrazine, which doesn't take low temperature very well. In fact, it freezes about like water. We started adding unsymmetrical-dimethylhydrazine (UDMH) to the hydrazine until such time as it would meet the environmental specifications the Air Force needed for Titan II. It turned out it s roughly a fifty-fifty mix. We still had to be careful with that fuel because the two fluids didn't mix very well chemically. We had to spray the two fluids through some special nozzles to get them to emulsify with each other into a single fluid. If we ever got it too cold or froze it, the hydrazine separated back out. Then, if we tried to run the engine, things could go boom in the night. The inlet pressure was only 165 pounds per square inch absolute (psia), but we needed at least forty psi pressure drop across the injector just to get some kind of stable flow. It was a whole new game for some of us. We didn't have much supply pressure to work with. It had the aluminum injector to keep the weight down. That was a couple feet in diameter, and we didn't have a lot of propellant to cool it. In fact, we had to use both propellants to keep the injector cool. There were twenty-two ring channels in the injector. Specification required 750 seconds duration, or fifty engine restarts during a flight. There were several first flight things we accomplished with the engine. It was the first ablative thrust chamber of any size to fly. (See Slide 6, Appendix G) There were no liners in it. It was just straight ablative material. It took us a while to figure that out. It was a throat-gimbaled engine, and it was the first engine to fly with columbium (also known as niobium, used as an alloying element in steels and superalloys) in the nozzle.

  4. UAV Mission Optimization through Hybrid-Electric Propulsion

    NASA Astrophysics Data System (ADS)

    Blackwelder, Philip Scott

    Hybrid-electric powertrain leverages the superior range of petrol based systems with the quiet and emission free benefits of electric propulsion. The major caveat to hybrid-electric powertrain in an airplane is that it is inherently heavier than conventional petroleum powertrain due mostly to the low energy density of battery technology. The first goal of this research is to develop mission planning code to match powertrain components for a small-scale unmanned aerial vehicle (UAV) to complete a standard surveillance mission within a set of user input parameters. The second goal is to promote low acoustic profile loitering through mid-flight engine starting. The two means by which midmission engine starting will be addressed is through reverse thrust from the propeller and a servo actuated gear to couple and decouple the engine and motor. The mission planning code calculates the power required to complete a mission and assists the user in sourcing powertrain components including the propeller, motor, battery, motor controller, engine and fuel. Reverse thrust engine starting involves characterizing an off the shelf variable pitch propeller and using its torque coefficient to calculate the advance ratio required to provide sufficient torque and speed to start an engine. Geared engine starting works like the starter in a conventional automobile. A servo actuated gear will couple the motor to the engine to start it and decouple once the engine has started. Reverse thrust engine starting was unsuccessful due to limitations of available off the shelf variable pitch propellers. However, reverse thrust engine starting could be realized through a custom larger diameter propeller. Geared engine starting was a success, though the system was unable to run fully as intended. Due to counter-clockwise crank rotation of the engine and the right-hand threads on the crankshaft, cranking the engine resulted in the nut securing the engine starter gear to back off as the engine cranked. A second nut was added to secure the starter gear but at the expense of removing the engine drive pulley. Removing the engine pulley meant that the starter gear must remain engaged to transmit torque to the propeller shaft as opposed to the engine pulley. This issue can be resolved using different hardware, however changing the mounting hardware would require additional modifications to the associated component which time would not permit. Though battery technology still proves to be the main constraint of electrified powertrain, careful design and mission planning can help minimize the weight penalties incurred. The mission planning code complements previous research by comparing the weight penalties of a blended climb versus an engine only climb and selecting the lightest option. Though reverse thrust engine starting proved unsuccessful, the success of geared engine starting now allows the engine to be shut off during loiter reducing both acoustic profile and fuel consumption during loiter.

  5. Commercial Motor Vehicle (CMV) Driver Restart Study: Final Report

    DOT National Transportation Integrated Search

    2017-03-01

    A congressionally-mandated naturalistic study was conducted to evaluate the operational, safety, fatigue, and health impacts of the restart provisions in Sections 395.3(c) and 395.3(d) of Title 49, Code of Federal Regulations. A total of 235 commerci...

  6. Replication restart in UV-irradiated Escherichia coli involving pols II, III, V, PriA, RecA and RecFOR proteins.

    PubMed

    Rangarajan, Savithri; Woodgate, Roger; Goodman, Myron F

    2002-02-01

    In Escherichia coli, UV-irradiated cells resume DNA synthesis after a transient inhibition by a process called replication restart. To elucidate the role of several key proteins involved in this process, we have analysed the time dependence of replication restart in strains carrying a combination of mutations in lexA, recA, polB (pol II), umuDC (pol V), priA, dnaC, recF, recO or recR. We find that both pol II and the origin-independent primosome-assembling function of PriA are essential for the immediate recovery of DNA synthesis after UV irradiation. In their absence, translesion replication or 'replication readthrough' occurs approximately 50 min after UV and is pol V-dependent. In a wild-type, lexA+ background, mutations in recF, recO or recR block both pathways. Similar results were obtained with a lexA(Def) recF strain. However, lexA(Def) recO or lexA(Def) recR strains, although unable to facilitate PriA-pol II-dependent restart, were able to perform pol V-dependent readthrough. The defects in restart attributed to mutations in recF, recO or recR were suppressed in a recA730 lexA(Def) strain expressing constitutively activated RecA (RecA*). Our data suggest that in a wild-type background, RecF, O and R are important for the induction of the SOS response and the formation of RecA*-dependent recombination intermediates necessary for PriA/Pol II-dependent replication restart. In con-trast, only RecF is required for the activation of RecA that leads to the formation of pol V (UmuD'2C) and facilitates replication readthrough.

  7. Detection of combustion start in the controlled auto ignition engine by wavelet transform of the engine block vibration signal

    NASA Astrophysics Data System (ADS)

    Kim, Seonguk; Min, Kyoungdoug

    2008-08-01

    The CAI (controlled auto ignition) engine ignites fuel and air mixture by trapping high temperature burnt gas using a negative valve overlap. Due to auto ignition in CAI combustion, efficiency improvements and low level NOx emission can be obtained. Meanwhile, the CAI combustion regime is restricted and control parameters are limited. The start of combustion data in the compressed ignition engine are most critical for controlling the overall combustion. In this research, the engine block vibration signal is transformed by the Meyer wavelet to analyze CAI combustion more easily and accurately. Signal acquisition of the engine block vibration is a more suitable method for practical use than measurement of in-cylinder pressure. A new method for detecting combustion start in CAI engines through wavelet transformation of the engine block vibration signal was developed and results indicate that it is accurate enough to analyze the start of combustion. Experimental results show that wavelet transformation of engine block vibration can track the start of combustion in each cycle. From this newly developed method, the start of combustion data in CAI engines can be detected more easily and used as input data for controlling CAI combustion.

  8. Checkpoint-dependent RNR induction promotes fork restart after replicative stress.

    PubMed

    Morafraile, Esther C; Diffley, John F X; Tercero, José Antonio; Segurado, Mónica

    2015-01-20

    The checkpoint kinase Rad53 is crucial to regulate DNA replication in the presence of replicative stress. Under conditions that interfere with the progression of replication forks, Rad53 prevents Exo1-dependent fork degradation. However, although EXO1 deletion avoids fork degradation in rad53 mutants, it does not suppress their sensitivity to the ribonucleotide reductase (RNR) inhibitor hydroxyurea (HU). In this case, the inability to restart stalled forks is likely to account for the lethality of rad53 mutant cells after replication blocks. Here we show that Rad53 regulates replication restart through the checkpoint-dependent transcriptional response, and more specifically, through RNR induction. Thus, in addition to preventing fork degradation, Rad53 prevents cell death in the presence of HU by regulating RNR-expression and localization. When RNR is induced in the absence of Exo1 and RNR negative regulators, cell viability of rad53 mutants treated with HU is increased and the ability of replication forks to restart after replicative stress is restored.

  9. Mathematical model and metaheuristics for simultaneous balancing and sequencing of a robotic mixed-model assembly line

    NASA Astrophysics Data System (ADS)

    Li, Zixiang; Janardhanan, Mukund Nilakantan; Tang, Qiuhua; Nielsen, Peter

    2018-05-01

    This article presents the first method to simultaneously balance and sequence robotic mixed-model assembly lines (RMALB/S), which involves three sub-problems: task assignment, model sequencing and robot allocation. A new mixed-integer programming model is developed to minimize makespan and, using CPLEX solver, small-size problems are solved for optimality. Two metaheuristics, the restarted simulated annealing algorithm and co-evolutionary algorithm, are developed and improved to address this NP-hard problem. The restarted simulated annealing method replaces the current temperature with a new temperature to restart the search process. The co-evolutionary method uses a restart mechanism to generate a new population by modifying several vectors simultaneously. The proposed algorithms are tested on a set of benchmark problems and compared with five other high-performing metaheuristics. The proposed algorithms outperform their original editions and the benchmarked methods. The proposed algorithms are able to solve the balancing and sequencing problem of a robotic mixed-model assembly line effectively and efficiently.

  10. A novel transient wall heat transfer approach for the start-up of SI engines with gasoline direct injection

    NASA Astrophysics Data System (ADS)

    Lejsek, David; Kulzer, André; Hammer, Jürgen

    2010-11-01

    The introduction of CO2-reduction technologies like Start-Stop or the Hybrid-Powertrain and the worldwide stringent emission legislation require a detailed optimization of the engine start-up. The combustion concept development as well as the calibration of the engine control unit makes an explicit thermodynamic analysis of the combustion process during the start-up necessary. Initially, the well-known thermodynamic analysis of in-cylinder pressure at stationary condition was transmitted to the highly non-stationary engine start-up. For this running mode of the engine the current models for calculation of the transient wall heat fluxes were found to be misleading. With a fraction of nearly 45% of the burned fuel energy, the wall heat is very important for the calculation of energy balance and for the combustion process analysis. Based on the measurements of transient wall heat transfer densities during the start-up presented in a former work (Lejsek and Kulzer in Investigations on the transient wall heat transfer at start-up for SI engines with gasoline direct injection. SAE Paper), the paper describes the development of adaptations to the known correlations by Woschni (MTZ 31:491, 1970), Hohenberg (Experimentelle Erfassung der Wandwärme von Kolbenmotoren. TU Graz, Habil., 1980) and Bargende (Ein Gleichungsansatz zur Berechnung der instationären Wandwärmeverluste im Hochdruckteil von Ottomotoren. TH Darmstadt, PhD-Thesis, 1991) for the application during engine start-up. To demonstrate the high accuracy of the model, the results of the cyclic resolved thermodynamic analysis using the presented novel approaches were compared with the results of the measurements. It is shown, that the novel heat flux models for the engine start-up process gives a cyclic resolved thermodynamic analysis to optimize the engine start-up pretty efficient.

  11. 40 CFR 60.5120 - What must I do if I close my SSI unit and then restart it?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Existing Sewage Sludge Incineration Units Model Rule-Increments of Progress... standards, and operating limits on the date your unit restarts operation. ...

  12. A 15,000-hour cyclic endurance test of an 8-centimeter-diameter electron bombardment mercury ion thruster

    NASA Technical Reports Server (NTRS)

    Nakanishi, S.

    1976-01-01

    A laboratory model 8 cm thruster with improvements to minimize ion chamber erosion and peeling of sputtered metal was subjected to a cyclic endurance test for 15,040 hours and 460 restarts. A charted history of several thruster operating variables and off-normal events are shown in 600-hour segments at three points in the test. The transient behavior of these variables during a typical start-stop cycle is presented. Finding of the post-test inspection confirmed most of the expected results. Charge exchange ions caused normal accelerator grid erosion. The workability of the various design features was substantiated, and attainable improvements in propellant utilization efficiency should significantly reduce accelerator erosion.

  13. Backup control airstart performance on a digital electronic engine control-equipped F100-engine

    NASA Technical Reports Server (NTRS)

    Johnson, J. B.

    1984-01-01

    The air start capability of a backup control (BUC) was tested for a digital electronic engine control (DEEC) equipped F100 engine, which was installed in an F-15 aircraft. Two air start schedules were tested. Using the group 1 start schedule, based on a 40 sec timer, an air speed of 300 knots was required to ensure successful 40 and 25% BUC mode spooldown airstarts. If core rotor speed (N2) was less than 40% a stall would occur when the start bleed closed, 40 sec after initiation of the air start. All jet fuel starter (JFS) assisted air starts were successful with the group 1 start schedule. For the group 2 schedule, the time between pressurization and start bleed closure ranged between 50 sec and 72 sec. Idle rps was lower than the desired 65% for air starts at higher altitudes and lower air speeds.

  14. Method for reducing peak phase current and decreasing staring time for an internal combustion engine having an induction machine

    DOEpatents

    Amey, David L.; Degner, Michael W.

    2002-01-01

    A method for reducing the starting time and reducing the peak phase currents for an internal combustion engine that is started using an induction machine starter/alternator. The starting time is reduced by pre-fluxing the induction machine and the peak phase currents are reduced by reducing the flux current command after a predetermined period of time has elapsed and concurrent to the application of the torque current command. The method of the present invention also provides a strategy for anticipating the start command for an internal combustion engine and determines a start strategy based on the start command and the operating state of the internal combustion engine.

  15. Initiation of Basal Insulin Analog Treatment for Type 2 Diabetes and Reasons Behind Patients' Treatment Persistence Behavior: Real-World Data from Germany.

    PubMed

    Moennig, Elisabeth; Perez-Nieves, Magaly; Hadjiyianni, Irene; Cao, Dachuang; Ivanova, Jasmina; Klask, Ralf

    2018-05-01

    Poor treatment persistence can affect the real-world effectiveness of insulin therapy. A cross-sectional online survey in 942 patients with type 2 diabetes from 7 different countries evaluated patient experience when initiating basal insulin and the reasons behind insulin persistence patterns. Here, we report the quantitative results for the subset of patients from Germany. Adults with type 2 diabetes who had initiated basal insulin during the last 3-24 months, identified from market-research panels, participated in the survey. Patients were asked if they had ≥7-day gaps in basal insulin treatment, and were then classified as "continuers" (no gap since starting insulin), "interrupters" (≥1 gap within the first 6 months after starting insulin and subsequently restarted insulin), or "discontinuers" (stopped insulin within the first 6 months after starting and had not restarted at the time of the survey). For each country, 50 participants were planned per persistence category. Enrollment ended if the target quota was reached or enrollment plateaued. Data were analyzed overall and separately for each persistence cohort. The 131 participants from Germany included 55 (42.0%) continuers, 50 (38.2%) interrupters and 26 (19.9%) discontinuers. The most common motivations to initiate basal insulin therapy were encouragement by physician or other healthcare provider (HCP; 54.2%) and expectation to improve glycemic control (42.0%). More than 95% of participants received training before and during insulin initiation (considered as helpful by 81.7%); most (67.2%) preferred in-person training. Continuers more frequently felt that insulin would help to manage diabetes and that their own views were considered when initiating insulin, they reported less concerns and challenges before and during insulin initiation than interrupters or discontinuers. The most common motivations to continue basal insulin were improved glycemic control (72.7%), improved physical well-being (49.1%), and instruction by physician or other HCP (45.5%). The most common reasons contributing to interruption/discontinuation were perceived weight gain (52.0%/50.0%), hypoglycemia (22.0%/38.5%), and potential adverse effects (30.0%/26.9%). Quality interactions between physicians or other HCPs and their patients before and during the initiation of basal insulin may help to manage patient expectations and to improve persistence to insulin therapy. © Georg Thieme Verlag KG Stuttgart · New York.

  16. 77 FR 65419 - Virginia Electric and Power Company

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-26

    ... restart for North Anna 1 and 2, after the earthquake of August 23, 2011, Virginia Electric and Power... reevaluates the plant's design basis for earthquakes and for associated necessary retrofits. (2) Prior to the approval of restart for North Anna 1 and 2, after the earthquake of August 23, 2011, the licensee should be...

  17. Restartable solid motor stage for shuttle applications

    NASA Technical Reports Server (NTRS)

    Rohrbaugh, D. J.

    1973-01-01

    The application of restartable solid motor stages to shuttle missions has been shown to provide a viable supplement to the shuttle program. Restartable solid motors in the 3000 pound class provide a small expendable transfer stage that reduces the demand on the shuttle for the lower energy missions. Shuttle operational requirements and preliminary performance data provided an input for defining design features required for restartable solid motor applications. These data provided a basis for a configuration definition that is compatible with shuttle operations. Mission by mission analysis showed the impact on a NASA supplied mission model. The results showed a 15% reduction in the number of shuttle flights required. In addition the amount of shuttle capability used to complete the mission objectives was significantly reduced. For example, in the 1979 missions there was a 62% reduction in shuttle capability used. The study also showed that the solid motor could provide a supplement to the TUG that would allow TUGS to be used in a recoverable rather than an expendable mode. The study shows a 71% reduction in the number of TUGs that would be expended.

  18. Advanced transportation system studies, technical area 3. Alternate propulsion subsystem concepts: J-2S restart study

    NASA Astrophysics Data System (ADS)

    Vilja, John; Levack, Daniel

    1993-04-01

    The objectives were to assess what design changes would be required to remit late production of the J-2S engine for use as a large high energy upper stage engine. The study assessed design changes required to perform per the J-2S model specification, manufacturing changes required due to obsolescence or improvements in state-of-the-practice, availability issues for supplier provided items, and provided cost and schedule estimates for this configuration. The confidence that J-2S production could be reinitiated within reasonable costs and schedules was provided. No significant technical issues were identified in either the producibility study or in the review of previous technical data. Areas of potential cost reduction were identified which could be quantified to a greater extent with further manufacturing planning. The proposed schedule can be met with no foreseeable impacts. The results of the study provided the necessary foundation for the detailed manufacturing and test plans and non-recurring and recurring cost estimates that are needed to complete the effort to reinitiate production of the J-2S engine system.

  19. NASA chooses hybrid power system for Space Station

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Holt, D.J.

    1986-06-01

    The hybrid solar power system being developed for the Space Station is characterized. Major components of the 75-kW system required for the initial operational phase of the Station are 25-kW photovoltaic arrays (with Ni-H storage batteries for eclipse-phase power and some means of conversion to ac for distribution) and a 50-kW solar dynamic system comprising a reflecting concentrator, a thermal-energy storage unit, and a heat engine based either on an organic Rankine cycle (described by Holt, 1985) or on a closed Brayton cycle. The design and operating principle of a Brayton-cycle engine using an He-Xe mixture as the working fluid,more » gas-foil journal bearings, an LiF/MgF2 thermal-storage unit, and a 95-percent-effectiveness plate-fin-type recuperator are described and illustrated with drawings. This engine is designed to operate at 25,000-50,000 rpm with overall day/night cycle efficiency 27.6 percent for 95-min orbits, and to be restartable under zero-g conditions.« less

  20. Engine starting and stopping

    NASA Astrophysics Data System (ADS)

    Curnock, Barry

    Different starter systems for jet engines are discussed: electric, cartridge, iso-propyl-nitrate, air, gas turbine, and hydraulic. The fuel system, ignition system, air flow control system, and actual starting mechanism of an air starter motor system are considered. The variation of engine parameters throughout a typical starting sequence are described, with reference to examples for an RB211-535 engine. Physical constraints on engine starting are considered: rotating stall, light up, the window between hang and stall, hang, compressor stall, and the effects of ambient conditions. The following are also discussed: contractual and airworthiness requirements; windmilling; inflight relighting; afterburning light up; combustion stability; and broken shafts. Graphics illustrating the above are presented.

  1. AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT XXVII, I--CATERPILLAR STARTING (PONEY) ENGINE (PART I), II--LEARNING ABOUT BRAKES (PART II).

    ERIC Educational Resources Information Center

    Minnesota State Dept. of Education, St. Paul. Div. of Vocational and Technical Education.

    THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE CONSTRUCTION AND OPERATION OF DIESEL ENGINE STARTING ENGINES AND BRAKE SYSTEMS USED ON DIESEL POWERED VEHICLES. TOPICS ARE (1) GENERAL DESCRIPTION, (2) OPERATION, (3) COMBUSTION SPACE AND VALVE ARRANGEMENT (STARTING ENGINES), (4) TYPES OF BRAKES, AND (5) DOUBLE…

  2. Airstart performance of a digital electronic engine control system on an F100 engine

    NASA Technical Reports Server (NTRS)

    Burcham, F. W., Jr.

    1984-01-01

    The digital electronic engine control (DEEC) system installed on an F100 engine in an F-15 aircraft was tested. The DEEC system incorporates a closed-loop air start feature in which the fuel flow is modulated to achieve the desired rate of compressor acceleration. With this logic the DEEC equipped F100 engine can achieve air starts over a larger envelope. The DEEC air start logic, the test program conducted on the F-15, and its results are described.

  3. Extending Clause Learning of SAT Solvers with Boolean Gröbner Bases

    NASA Astrophysics Data System (ADS)

    Zengler, Christoph; Küchlin, Wolfgang

    We extend clause learning as performed by most modern SAT Solvers by integrating the computation of Boolean Gröbner bases into the conflict learning process. Instead of learning only one clause per conflict, we compute and learn additional binary clauses from a Gröbner basis of the current conflict. We used the Gröbner basis engine of the logic package Redlog contained in the computer algebra system Reduce to extend the SAT solver MiniSAT with Gröbner basis learning. Our approach shows a significant reduction of conflicts and a reduction of restarts and computation time on many hard problems from the SAT 2009 competition.

  4. An Experimental Study on the Darrieus-Savonius Turbine for the Tidal Current Power Generation

    NASA Astrophysics Data System (ADS)

    Kyozuka, Yusaku

    The Darrieus turbine is popular for tidal current power generation in Japan. It is simple in structure with straight wings rotating around a vertical axis, so that it has no directionality against the motion of tidal flow which changes its direction twice a day. However, there is one defect in the Darrieus turbine; its small starting torque. Once it stops, a Darrieus turbine is hard to re-start until a fairly fast current is exerted on it. To improve the starting torque of the Darrieus turbine used for tidal power generation, a hybrid turbine, composed of a Darrieus turbine and a Savonius rotor is proposed. Hydrodynamic characteristics of a semi-circular section used for the Savonius bucket were measured in a wind tunnel. The torque of a two bucket Savonius rotor was measured in a circulating water channel, where four different configurations of the bucket were compared. A combined Darrieus and Savonius turbine was tested in the circulating water channel, where the effect of the attaching angle between Darrieus wing and Savonius rotor was studied. Finally, power generation experiments using a 48 pole electric generator were conducted in a towing tank and the power coefficients were compared with the results of experiments obtained in the circulating water channel.

  5. [The library of the Society of the Dutch Journal of Medicine].

    PubMed

    Molenaar, J C

    2004-11-20

    This year the library of the Vereniging Nederlands Tijdschrift voor Geneeskunde (Society of the Dutch Journal of Medicine) has reached the age of go. The idea was born in 1900 when the editor-in-chief M.Straub proposed starting a library for the Journal. This was rejected by the members of the Society, but fourteen years later, in 1914, when the new editor-in-chief G.A. van Rijnberk made a similar proposal, it was accepted. His long-term as editor (1913-1946) would prove to be a guarantee for the acquisition of a large collection of books, both antique and contemporary. The collection reflects the history of medicine, notably in The Netherlands, but also in a wider sense. Over the years, several catalogues of the collection have been published, and this year has seen the completion of an electronic catalogue which is available on the Internet (www.ntvg.nl). The acquisition and restoration of books have been re-started in the past five years and a fellowship for the study of the existing collection of books has been instituted.

  6. Eosinophilia and parotitis occurring early in clozapine treatment.

    PubMed

    Saguem, Bochra Nourhène; Bouhlel, Saoussen; Ben Salem, Chaker; Ben Hadj Ali, Bechir

    2015-12-01

    Mr. S is a 32-year-old male with schizophrenia. Due to poor responses to various antipsychotic medications, he was started on clozapine with the dose titrated to 300 mg/day during a 4-week period. The weekly checks of the complete blood cell count showed gradual increases in the eosinophil count from normal values to 4320 per mm(3). Mr. S did not have any symptoms except some increased salivation. Clozapine was suspended, and eosinophils gradually began to decline to the normal range. Clozapine was subsequently re-started and there were no changes in eosinophil counts. Mr. S exhibited improvement of symptoms but complained of acute auricular pain and increased salivation, 8 weeks after clozapine rechallenge. He also developed a swelling of his both parotid glands. The diagnosis of clozapine-induced parotitis was suggested. Symptomatic medication was prescribed with a favorable outcome. We report a case of a patient who developed eosinophilia shortly after clozapine use, and then developed parotitis. There is debate in the literature over how to manage these complications of clozapine treatment. Generally they do not warrant clozapine discontinuation.

  7. On the effect of Di-Ethyl-Ether (DEE) injection upon the cold starting of a biodiesel fuelled compression ignition engine

    NASA Astrophysics Data System (ADS)

    Clenci, Adrian; Niculescu, Rodica; Iorga-Simǎn, Victor; Tricǎ, Alina; Danlos, Amélie

    2017-02-01

    The use of biodiesel fuel in compression ignition engines has the potential to reduce CO2, which can lead to a reduction in global warming and environmental hazards. Biodiesel is an attractive fuel, as it is made from renewable resources. A major drawback associated with the use of biodiesel, however, is its poor cold flow properties, which have a direct influence on the cold starting performance of the engine. This paper is a consequence of a study on assessing the cold-starting performance of a compression ignition engine fueled with different blends of fossil diesel fuel and biodiesel. Through experimental investigations, it was found that the engine starting at -20°C was no longer possible in the case of using B50 (50% diesel + 50% biofuel made from sunflower oil). In order to "force" the engine starting in this particular situation, Di-Ethyl-Ether (DEE) was injected into the intake manifold. DEE being a highly flammable substance, the result was a sudden and explosive engine starting, the peak pressure in the monitored cylinder in the first successful engine cycle being almost twice the one which is usually considered as normal. Thus, to explain the observed phenomena, we launched this work relying on the analysis of the in-cylinder instantaneous pressure evolution, which was acquired during cranking, stabilizing and idling phases. Moreover, since the cause of the sudden and explosive engine starting was the DEE, by using a CFD approach, we also obtained results regarding the inter-cylinder distribution of the injected DEE.

  8. Successful Osimertinib Rechallenge with Steroid Therapy after Osimertinib-induced Interstitial Lung Disease.

    PubMed

    Kiriu, Tatsunori; Tamura, Daisuke; Tachihara, Motoko; Sekiya, Reina; Hazama, Daisuke; Katsurada, Masahiro; Nakata, Kyosuke; Nagano, Tatsuya; Yamamoto, Masatsugu; Kamiryo, Hiroshi; Kobayashi, Kazuyuki; Nishimura, Yoshihiro

    2018-01-01

    A 62-year-old male with lung adenocarcinoma harboring an exon 19 deletion in the Epidermal growth factor receptor (EGFR) was treated with EGFR-tyrosine kinase inhibitors (TKIs) and several cytotoxic agents. After administering a fifth-line chemotherapy regimen, a liver biopsy revealed a diagnosis of recurrence with a T790M mutation. After an 82-day course of osimertinib therapy, the patient developed osimertinib-induced interstitial lung disease (ILD). Osimertinib was discontinued, and oral prednisolone was started. The ILD quickly improved, but liver metastases progressed and osimertinib was restarted concurrently with prednisolone. The patient showed neither disease progression nor a recurrence of ILD at 5 months. In situations in which no alternative treatment is available, osimertinib rechallenge should thus be considered as an alternative treatment.

  9. Successful Osimertinib Rechallenge with Steroid Therapy after Osimertinib-induced Interstitial Lung Disease

    PubMed Central

    Kiriu, Tatsunori; Tamura, Daisuke; Tachihara, Motoko; Sekiya, Reina; Hazama, Daisuke; Katsurada, Masahiro; Nakata, Kyosuke; Nagano, Tatsuya; Yamamoto, Masatsugu; Kamiryo, Hiroshi; Kobayashi, Kazuyuki; Nishimura, Yoshihiro

    2017-01-01

    A 62-year-old male with lung adenocarcinoma harboring an exon 19 deletion in the Epidermal growth factor receptor (EGFR) was treated with EGFR-tyrosine kinase inhibitors (TKIs) and several cytotoxic agents. After administering a fifth-line chemotherapy regimen, a liver biopsy revealed a diagnosis of recurrence with a T790M mutation. After an 82-day course of osimertinib therapy, the patient developed osimertinib-induced interstitial lung disease (ILD). Osimertinib was discontinued, and oral prednisolone was started. The ILD quickly improved, but liver metastases progressed and osimertinib was restarted concurrently with prednisolone. The patient showed neither disease progression nor a recurrence of ILD at 5 months. In situations in which no alternative treatment is available, osimertinib rechallenge should thus be considered as an alternative treatment. PMID:29033419

  10. Actuator stiction compensation via variable amplitude pulses.

    PubMed

    Arifin, B M S; Munaro, C J; Angarita, O F B; Cypriano, M V G; Shah, S L

    2018-02-01

    A novel model free stiction compensation scheme is developed which eliminates the oscillations and also reduces valve movement, allowing good setpoint tracking and disturbance rejection. Pulses with varying amplitude are added to the controller output to overcome stiction and when the error becomes smaller than a specified limit, the compensation ceases and remains in a standby mode. The compensation re-starts as soon as the error exceeds the user specified threshold. The ability to cope with uncertainty in friction is a feature achieved by the use of pulses of varying amplitude. The algorithm has been evaluated via simulation and by application on an industrial DCS system interfaced to a pilot scale process with features identical to those found in industry including a valve positioner. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  11. Heparin-induced hyperkalemia.

    PubMed

    Thomas, C M; Thomas, J; Smeeton, F; Leatherdale, B A

    2008-05-01

    An 85-year-old lady with type 2 diabetes mellitus of 32 years duration with peripheral neuropathy was admitted under the vascular surgeons with extensive gangrene of her lower limb. She was on insulin for the last 7 years. Initial investigations showed normal serum electrolytes. She was started on antibiotics and unfractionated heparin, and her electrolytes showed hyperkalemia, which persisted on active treatment. Her short synacthen test showed good response, renin was normal with low aldosterone, urinary pH, sodium, potassium and osmolality was normal. On stopping heparin serum, potassium became normal. On restarting heparin (low molecular weight) during a suspected episode of pulmonary embolism, she developed hyperkalemia and heparin was stopped. Her potassium and aldosterone became normal on discontinuation of heparin. She developed hyperkalemia with both unfractionated and low molecular weight heparin.

  12. Continuous-time random walks with reset events. Historical background and new perspectives

    NASA Astrophysics Data System (ADS)

    Montero, Miquel; Masó-Puigdellosas, Axel; Villarroel, Javier

    2017-09-01

    In this paper, we consider a stochastic process that may experience random reset events which relocate the system to its starting position. We focus our attention on a one-dimensional, monotonic continuous-time random walk with a constant drift: the process moves in a fixed direction between the reset events, either by the effect of the random jumps, or by the action of a deterministic bias. However, the orientation of its motion is randomly determined after each restart. As a result of these alternating dynamics, interesting properties do emerge. General formulas for the propagator as well as for two extreme statistics, the survival probability and the mean first-passage time, are also derived. The rigor of these analytical results is verified by numerical estimations, for particular but illuminating examples.

  13. Mouse embryonic stem cells have increased capacity for replication fork restart driven by the specific Filia-Floped protein complex.

    PubMed

    Zhao, Bo; Zhang, Weidao; Cun, Yixian; Li, Jingzheng; Liu, Yan; Gao, Jing; Zhu, Hongwen; Zhou, Hu; Zhang, Rugang; Zheng, Ping

    2018-01-01

    Pluripotent stem cells (PSCs) harbor constitutive DNA replication stress during their rapid proliferation and the consequent genome instability hampers their applications in regenerative medicine. It is therefore important to understand the regulatory mechanisms of replication stress response in PSCs. Here, we report that mouse embryonic stem cells (ESCs) are superior to differentiated cells in resolving replication stress. Specifically, ESCs utilize a unique Filia-Floped protein complex-dependent mechanism to efficiently promote the restart of stalled replication forks, therefore maintaining genomic stability. The ESC-specific Filia-Floped complex resides on replication forks under normal conditions. Replication stress stimulates their recruitment to stalling forks and the serine 151 residue of Filia is phosphorylated in an ATR-dependent manner. This modification enables the Filia-Floped complex to act as a functional scaffold, which then promotes the stalling fork restart through a dual mechanism: both enhancing recruitment of the replication fork restart protein, Blm, and stimulating ATR kinase activation. In the Blm pathway, the scaffolds recruit the E3 ubiquitin ligase, Trim25, to the stalled replication forks, and in turn Trim25 tethers and concentrates Blm at stalled replication forks through ubiquitination. In differentiated cells, the recruitment of the Trim25-Blm complex to replication forks and the activation of ATR signaling are much less robust due to lack of the ESC-specific Filia-Floped scaffold. Thus, our study reveals that ESCs utilize an additional and unique regulatory layer to efficiently promote the stalled fork restart and maintain genomic stability.

  14. PriC-mediated DNA replication restart requires PriC complex formation with the single-stranded DNA-binding protein.

    PubMed

    Wessel, Sarah R; Marceau, Aimee H; Massoni, Shawn C; Zhou, Ruobo; Ha, Taekjip; Sandler, Steven J; Keck, James L

    2013-06-14

    Frequent collisions between cellular DNA replication complexes (replisomes) and obstacles such as damaged DNA or frozen protein complexes make DNA replication fork progression surprisingly sporadic. These collisions can lead to the ejection of replisomes prior to completion of replication, which, if left unrepaired, results in bacterial cell death. As such, bacteria have evolved DNA replication restart mechanisms that function to reload replisomes onto abandoned DNA replication forks. Here, we define a direct interaction between PriC, a key Escherichia coli DNA replication restart protein, and the single-stranded DNA-binding protein (SSB), a protein that is ubiquitously associated with DNA replication forks. PriC/SSB complex formation requires evolutionarily conserved residues from both proteins, including a pair of Arg residues from PriC and the C terminus of SSB. In vitro, disruption of the PriC/SSB interface by sequence changes in either protein blocks the first step of DNA replication restart, reloading of the replicative DnaB helicase onto an abandoned replication fork. Consistent with the critical role of PriC/SSB complex formation in DNA replication restart, PriC variants that cannot bind SSB are non-functional in vivo. Single-molecule experiments demonstrate that PriC binding to SSB alters SSB/DNA complexes, exposing single-stranded DNA and creating a platform for other proteins to bind. These data lead to a model in which PriC interaction with SSB remodels SSB/DNA structures at abandoned DNA replication forks to create a DNA structure that is competent for DnaB loading.

  15. Ways of achieving continuous service from computers

    NASA Technical Reports Server (NTRS)

    Quinn, M. J., Jr.

    1974-01-01

    This paper outlines the methods used in the real-time computer complex to keep computers operating. Methods include selectover, high-speed restart, and low-speed restart. The hardware and software needed to implement these methods is discussed as well as the system recovery facility, alternate device support, and timeout. In general, methods developed while supporting the Gemini, Apollo, and Skylab space missions are presented.

  16. Understanding Victims of Technological Disaster: Beliefs and Worries of Three Mile Island.

    ERIC Educational Resources Information Center

    Prince-Embury, Sandra; Rooney, James

    The primary purpose of the present study was to examine how prevalent were concerns about restarting Three Mile Island nuclear reactor Unit I among people within a five-mile radius of the plant four years after the accident involving reactor Unit II. Also explored were concerns related to expectations about the restart of Unit I, perception of…

  17. 77 FR 18874 - Virginia Electric and Power Company; Receipt of Request for Action

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-28

    ... follows: (1) Prior to the approval of restart for North Anna 1 and 2, after the earthquake of August 23... reevaluates the plant's design basis for earthquakes and for associated retrofits. (2) Prior to the approval of restart for North Anna 1 and 2, after the earthquake of August 23, 2011, the licensee should be...

  18. Seismic waveform tomography with shot-encoding using a restarted L-BFGS algorithm.

    PubMed

    Rao, Ying; Wang, Yanghua

    2017-08-17

    In seismic waveform tomography, or full-waveform inversion (FWI), one effective strategy used to reduce the computational cost is shot-encoding, which encodes all shots randomly and sums them into one super shot to significantly reduce the number of wavefield simulations in the inversion. However, this process will induce instability in the iterative inversion regardless of whether it uses a robust limited-memory BFGS (L-BFGS) algorithm. The restarted L-BFGS algorithm proposed here is both stable and efficient. This breakthrough ensures, for the first time, the applicability of advanced FWI methods to three-dimensional seismic field data. In a standard L-BFGS algorithm, if the shot-encoding remains unchanged, it will generate a crosstalk effect between different shots. This crosstalk effect can only be suppressed by employing sufficient randomness in the shot-encoding. Therefore, the implementation of the L-BFGS algorithm is restarted at every segment. Each segment consists of a number of iterations; the first few iterations use an invariant encoding, while the remainder use random re-coding. This restarted L-BFGS algorithm balances the computational efficiency of shot-encoding, the convergence stability of the L-BFGS algorithm, and the inversion quality characteristic of random encoding in FWI.

  19. Rolls Royce Avon RA-14 Engine in the Altitude Wind Tunnel

    NASA Image and Video Library

    1956-03-21

    A Rolls Royce Avon RA-14 engine was tested in the Altitude Wind Tunnel at the National Advisory Committee for Aeronautics’ (NACA) Lewis Flight Propulsion Laboratory. The Avon RA-14 engine was a 16-stage axial-flow compressor turbojet capable of producing 9,500 pounds of thrust. The Avon replaced Rolls Royce’s successful Nene engine in 1950 and remained in service until 1974. It was one of several British engines studied in the tunnel during the 1950s. The Altitude Wind Tunnel went through a series of modifications in 1951 to increase its capabilities. An annex was attached to the Exhauster Building to house three new Ingersoll-Rand compressors. The wooden blades on the tunnel’s 31-foot diameter fan were replaced, a pump house and exhaust cooler were constructed underneath the tunnel, and two new cells were added to the cooling tower. The modified wind tunnel continued to analyze jet engines in the 1950s, although the engines, like the RA-14 seen here, were much more powerful than those studied several years before. Lewis researchers studied the RA-14 turbojet engine in the Altitude Wind Tunnel for 11 months in 1956. The engine was mounted on a stand capable of gauging engine thrust, and the tunnel’s air was ducted to the engine through a venturi and bellmouth inlet, seen in this photograph. The initial studies established the engine’s performance characteristics with a fixed-area nozzle and its acceleration characteristics. The researchers also used the tunnel to investigate windmilling of the compressor blades, restarting at high altitudes, and the engine’s performance limits at altitude.

  20. Shielding Development for Nuclear Thermal Propulsion

    NASA Technical Reports Server (NTRS)

    Caffrey, Jarvis A.; Gomez, Carlos F.; Scharber, Luke L.

    2015-01-01

    Radiation shielding analysis and development for the Nuclear Cryogenic Propulsion Stage (NCPS) effort is currently in progress and preliminary results have enabled consideration for critical interfaces in the reactor and propulsion stage systems. Early analyses have highlighted a number of engineering constraints, challenges, and possible mitigating solutions. Performance constraints include permissible crew dose rates (shared with expected cosmic ray dose), radiation heating flux into cryogenic propellant, and material radiation damage in critical components. Design strategies in staging can serve to reduce radiation scatter and enhance the effectiveness of inherent shielding within the spacecraft while minimizing the required mass of shielding in the reactor system. Within the reactor system, shield design is further constrained by the need for active cooling with minimal radiation streaming through flow channels. Material selection and thermal design must maximize the reliability of the shield to survive the extreme environment through a long duration mission with multiple engine restarts. A discussion of these challenges and relevant design strategies are provided for the mitigation of radiation in nuclear thermal propulsion.

  1. Modeling the internal combustion engine

    NASA Technical Reports Server (NTRS)

    Zeleznik, F. J.; Mcbride, B. J.

    1985-01-01

    A flexible and computationally economical model of the internal combustion engine was developed for use on large digital computer systems. It is based on a system of ordinary differential equations for cylinder-averaged properties. The computer program is capable of multicycle calculations, with some parameters varying from cycle to cycle, and has restart capabilities. It can accommodate a broad spectrum of reactants, permits changes in physical properties, and offers a wide selection of alternative modeling functions without any reprogramming. It readily adapts to the amount of information available in a particular case because the model is in fact a hierarchy of five models. The models range from a simple model requiring only thermodynamic properties to a complex model demanding full combustion kinetics, transport properties, and poppet valve flow characteristics. Among its many features the model includes heat transfer, valve timing, supercharging, motoring, finite burning rates, cycle-to-cycle variations in air-fuel ratio, humid air, residual and recirculated exhaust gas, and full combustion kinetics.

  2. Additional extensions to the NASCAP computer code, volume 3

    NASA Technical Reports Server (NTRS)

    Mandell, M. J.; Cooke, D. L.

    1981-01-01

    The ION computer code is designed to calculate charge exchange ion densities, electric potentials, plasma temperatures, and current densities external to a neutralized ion engine in R-Z geometry. The present version assumes the beam ion current and density to be known and specified, and the neutralizing electrons to originate from a hot-wire ring surrounding the beam orifice. The plasma is treated as being resistive, with an electron relaxation time comparable to the plasma frequency. Together with the thermal and electrical boundary conditions described below and other straightforward engine parameters, these assumptions suffice to determine the required quantities. The ION code, written in ASCII FORTRAN for UNIVAC 1100 series computers, is designed to be run interactively, although it can also be run in batch mode. The input is free-format, and the output is mainly graphical, using the machine-independent graphics developed for the NASCAP code. The executive routine calls the code's major subroutines in user-specified order, and the code allows great latitude for restart and parameter change.

  3. Soot formation in the methane oxygen and methane/oxygen/hydrogen flame

    NASA Technical Reports Server (NTRS)

    Dauerman, L.; Salser, G. E.

    1972-01-01

    The feasibility of using methane, recovered from carbon dioxide by the Sabatier-Senderens reaction, was investigated as a fuel in a reaction control engine. A problem to be avoided is the emission of soot particles. It is thought that such particles would remain in the environment of the spacecraft and, thereby, adversely affect optical sightings and possibly have an effect upon communications. The initial studies were of a practical nature. The first was the influence of the spatial arrangement of the fuel and oxygen injectors on soot formation. In the second study, inhibition of soot formation was considered. Considering the given situation, it was impractical to use an additive. However, since methanol combustion does not produce soot, and methanol can be produced from methane in situ, the possibility that methanol could act as an inhibitor was studied. In the third study, since these are restartable engines, the effect of shutdown on the rapidity of soot formation was studied.

  4. The Behaviour of the Military Battery Type BB248/U Used to Start the Engine of the A.P.C.

    DTIC Science & Technology

    1979-12-01

    UNCLASS IFIED I I ABSTRACT ~ ‘The performance of the lead—acid battery used to start the diesel engine ~~~~he Armoured Personnel Carrier...vehicle engines . One factor limiting the performance of this battery system is the very low Canadian winter temperatures, especially in Northern...information on the conditions of discharge inside the vehicle. For example, the military battery type BB248/U used to start the engine of the Armoured

  5. Stop/Start: Overview

    Science.gov Websites

    1 Stop/Start vehicles use a combination of regenerative and conventional friction braking to slow , The gasoline engine in a start-stop hybrid is much like those in conventional vehicles. Unlike other hybrids that use an electric motor to help power the vehicle, the engine in a start-stop hybrid is usually

  6. Start-up capabilities of photovoltaic module for the International Space Station

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hajela, G.; Hague, L.

    1997-12-31

    The International Space Station (ISS) uses four photovoltaic modules (PVMs) to supply electric power for the US On-Orbit Segment (USOS). The ISS is assembled on orbit over a period of about 5 years and over 40 stages. PVMs are launched and integrated with the ISS at different times during the ISS assembly. During early stages, the electric power is provided by the integrated truss segment (ITS) P6; subsequently, ITS P4, S4, and S6 are launched. PVMs are launched into space in the National Space Transportation System (NSTS) cargo bay. Each PVM consists of two independent power channels. The NSTS docksmore » with the ISS, the PVM is removed from the cargo bay and installed on the ISS. At this stage the PVM is in stowed configuration and its batteries are in fully discharged state. The start-up consists of initialization and checkout of all hardware, deployment of SAW and photovoltaic radiator (PVR), thermal conditioning batteries, and charging batteries; not necessarily in the same order for all PVMs. PVMs are designed to be capable of on-orbit start-up, within a specified time period, when external power is applied to a specified electrical interface. This paper describes the essential steps required for PVM start-up and how these operations are performed for various PVMs. The integrated operations scenarios (IOS) prepared by the NASA, Johnson Space Center, details specific procedures and timelines for start-up of each PVM. The paper describes how dormant batteries are brought to their normal operating temperature range and then charged to 100% state of charge (SOC). Total time required to complete start-up is computed and compared to the IOS timelines. External power required during start-up is computed and compared to the requirements and/or available power on ISS. Also described is how these start-up procedures can be adopted for restart of PVMs when required.« less

  7. Are lapsed donors willing to resume blood donation, and what determines their motivation to do so?

    PubMed

    van Dongen, Anne; Abraham, Charles; Ruiter, Robert A C; Schaalma, Herman P; de Kort, Wim L A M; Dijkstra, J Anneke; Veldhuizen, Ingrid J T

    2012-06-01

    This study investigated the possibility of rerecruiting lapsed blood donors. Reasons for donation cessation, motivation to restart donation, and modifiable components of donation motivation were examined. We distinguished between lapsed donors who had passively withdrawn by merely not responding to donation invitations and donors who had contacted the blood bank to actively withdraw. A cross-sectional survey was sent to 400 actively lapsed donors and to 400 passively lapsed donors, measuring intention to restart donation and psychological correlates of restart intention. The data were analyzed using multiple regression analyses. The response rate among actively lapsed donors was higher than among passively lapsed donors (37% vs. 25%). Actively lapsed donors typically ceased donating because of physical reactions, while passively lapsed donors quit because of a busy lifestyle. Nonetheless, 51% of actively lapsed responders and 80% of passively lapsed responders were willing to restart donations. Multiple regression analysis showed that, for passively lapsed donors, cognitive attitude was the strongest correlate of intention to donate in the future (β=0.605, p<0.001), with affective attitude (β=0.239, p<0.05) and self-efficacy (β=0.266, p<0.001) explaining useful proportions of the variance as well. For actively lapsed donors, cognitive attitude was also the strongest correlate of intention (β=0.601, p<0.001), with affective attitude (β=0.345, p<0.001) and moral norm (β=-0.118, p<0.05) explaining smaller proportions of the variance. The majority of lapsed donors indicated a moderate to high intention to restart donations. Interventions focusing on boosting cognitive and affective attitudes and self-efficacy could further raise such intentions. © 2011 American Association of Blood Banks.

  8. Checkpointing Shared Memory Programs at the Application-level

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bronevetsky, G; Schulz, M; Szwed, P

    2004-09-08

    Trends in high-performance computing are making it necessary for long-running applications to tolerate hardware faults. The most commonly used approach is checkpoint and restart(CPR)-the state of the computation is saved periodically on disk, and when a failure occurs, the computation is restarted from the last saved state. At present, it is the responsibility of the programmer to instrument applications for CPR. Our group is investigating the use of compiler technology to instrument codes to make them self-checkpointing and self-restarting, thereby providing an automatic solution to the problem of making long-running scientific applications resilient to hardware faults. Our previous work focusedmore » on message-passing programs. In this paper, we describe such a system for shared-memory programs running on symmetric multiprocessors. The system has two components: (i)a pre-compiler for source-to-source modification of applications, and (ii) a runtime system that implements a protocol for coordinating CPR among the threads of the parallel application. For the sake of concreteness, we focus on a non-trivial subset of OpenMP that includes barriers and locks. One of the advantages of this approach is that the ability to tolerate faults becomes embedded within the application itself, so applications become self-checkpointing and self-restarting on any platform. We demonstrate this by showing that our transformed benchmarks can checkpoint and restart on three different platforms (Windows/x86, Linux/x86, and Tru64/Alpha). Our experiments show that the overhead introduced by this approach is usually quite small; they also suggest ways in which the current implementation can be tuned to reduced overheads further.« less

  9. Plasma-enhanced mixing and flameholding in supersonic flow

    PubMed Central

    Firsov, Alexander; Savelkin, Konstantin V.; Yarantsev, Dmitry A.; Leonov, Sergey B.

    2015-01-01

    The results of experimental study of plasma-based mixing, ignition and flameholding in a supersonic model combustor are presented in the paper. The model combustor has a length of 600 mm and cross section of 72 mm width and 60 mm height. The fuel is directly injected into supersonic airflow (Mach number M=2, static pressure Pst=160–250 Torr) through wall orifices. Two series of tests are focused on flameholding and mixing correspondingly. In the first series, the near-surface quasi-DC electrical discharge is generated by flush-mounted electrodes at electrical power deposition of Wpl=3–24 kW. The scope includes parametric study of ignition and flame front dynamics, and comparison of three schemes of plasma generation: the first and the second layouts examine the location of plasma generators upstream and downstream from the fuel injectors. The third pattern follows a novel approach of combined mixing/ignition technique, where the electrical discharge distributes along the fuel jet. The last pattern demonstrates a significant advantage in terms of flameholding limit. In the second series of tests, a long discharge of submicrosecond duration is generated across the flow and along the fuel jet. A gasdynamic instability of thermal cavity developed after a deposition of high-power density in a thin plasma filament promotes the air–fuel mixing. The technique studied in this work has weighty potential for high-speed combustion applications, including cold start/restart of scramjet engines and support of transition regime in dual-mode scramjet and at off-design operation. PMID:26170434

  10. Commentary: restarting NTD programme activities after the Ebola outbreak in Liberia.

    PubMed

    Thomas, Brent C; Kollie, Karsor; Koudou, Benjamin; Mackenzie, Charles

    2017-05-01

    It is widely known that the recent Ebola Virus Disease (EVD) in West Africa caused a serious disruption to the national health system, with many of ongoing disease focused programmes, such as mass drug administration (MDA) for onchocerciasis (ONC), lymphatic filariasis (LF) and schistosomiasis (SCH), being suspended or scaled-down. As these MDA programmes attempt to restart post-EVD it is important to understand the challenges that may be encountered. This commentary addresses the opinions of the major health sectors involved, as well as those of community members, regarding logistic needs and challenges faced as these important public health programmes consider restarting. There appears to be a strong desire by the communities to resume NTD programme activities, although it is clear that some important challenges remain, the most prominent being those resulting from the severe loss of trained staff.

  11. Full Hybrid: Stopped

    Science.gov Websites

    than batteries used to start conventional vehicles. Main stage: See through car with battery, engine electric motor or stored in the battery. It is also used to start the gasoline engine instantly when needed used to start conventional vehicles

  12. Design of a 500 lbf liquid oxygen and liquid methane rocket engine for suborbital flight

    NASA Astrophysics Data System (ADS)

    Trillo, Jesus Eduardo

    Liquid methane (LCH4)is the most promising rocket fuel for our journey to Mars and other space entities. Compared to liquid hydrogen, the most common cryogenic fuel used today, methane is denser and can be stored at a more manageable temperature; leading to more affordable tanks and a lighter system. The most important advantage is it can be produced from local sources using in-situ resource utilization (ISRU) technology. This will allow the production of the fuel needed to come back to earth on the surface of Mars, or the space entity being explored, making the overall mission more cost effective by enabling larger usable mass. The major disadvantage methane has over hydrogen is it provides a lower specific impulse, or lower rocket performance. The UTEP Center for Space Exploration and Technology Research (cSETR) in partnership with the National Aeronautics and Space Administration (NASA) has been the leading research center for the advancement of Liquid Oxygen (LOX) and Liquid Methane (LCH4) propulsion technologies. Through this partnership, the CROME engine, a throattable 500 lbf LOX/LCH4 rocket engine, was designed and developed. The engine will serve as the main propulsion system for Daedalus, a suborbital demonstration vehicle being developed by the cSETR. The purpose of Daedalus mission and the engine is to fire in space under microgravity conditions to demonstrate its restartability. This thesis details the design process, decisions, and characteristics of the engine to serve as a complete design guide.

  13. Starting apparatus for internal combustion engines

    DOEpatents

    Dyches, Gregory M.; Dudar, Aed M.

    1997-01-01

    An internal combustion engine starting apparatus uses a signal from a curt sensor to determine when the engine is energized and the starter motor should be de-energized. One embodiment comprises a transmitter, receiver, computer processing unit, current sensor and relays to energize a starter motor and subsequently de-energize the same when the engine is running. Another embodiment comprises a switch, current transducer, low-pass filter, gain/comparator, relay and a plurality of switches to energize and de-energize a starter motor. Both embodiments contain an indicator lamp or speaker which alerts an operator as to whether a successful engine start has been achieved. Both embodiments also contain circuitry to protect the starter and to de-energize the engine.

  14. An Operating Environment for the Jellybean Machine

    DTIC Science & Technology

    1988-05-01

    MODEL 48 5.4.4 Restarting a Context The operating system provides one primitive message (RESTART-CONTEXT) and two system calls (XFERID and XFER.ADDR) to...efficient, powerful services is reqired to support this "stem. To provide this supportive operating environment, I developed an operating system kernel that...serves many of the initial needs of our machine. This Jellybean Operating System Software provides an object- based storage model, where typed

  15. Is magma cooling responsible for the periodic activity of Soufrière Hills volcano, Montserrat, West Indies?

    NASA Astrophysics Data System (ADS)

    Caricchi, Luca; Simpson, Guy; Chelle-Michou, Cyril; Neuberg, Jürgen

    2016-04-01

    After 400 years of quiescence, Soufrière Hills volcano on Montserrat (SHV) started erupting in 1995. Ongoing deformation and sulphur dioxide emission demonstrate that this volcanic systems is still restless, however, after 5 years of inactivity it remains unclear whether magma extrusion will restart. Also, if such periodically observed activity at SHV will restart, can we use past monitoring data to attempt to forecast the reawakening of this volcano? Cooling of volatile saturated magma leads to crystallisation, the formation of gas bubbles and expansion. Such volumetric variations are not only potentially responsible for deformation signals observed at the surface (Caricchi et al., 2014), but also lead to pressurisation of the magmatic reservoir and eventually renewed magma extrusion (Tait et al., 1989). We postulate that volcanic activity observed at SHM over the last 20 years could be essentially the result of the unavoidable progressive cooling of a magmatic body, which was probably assembled over thousands of years and experienced internal segregation of eruptible lenses of magma (Christopher et al., 2015). To test this hypothesis, we performed thermal modelling to test if the cooling of a shallow magma body emplaced since 1990 could account for the monitoring signals observed at SHV. The results show that progressive cooling of a 4km3 volume of melt could explain the deformation rate currently observed. Using the deformation rate obtained from the modelling for the first 15 years of cooling, a reservoir volume of about 13 km3 (Paulatto et al., 2012) and a critical value of overpressure of 10 MPa, it would have taken approximately only 3 years to pressurise the reservoir to the critical pressure and restart magma extrusion. This is in agreement with the time interval between previous pauses at SHV before 2010. Considering the current deformation rates, we speculate that magma extrusion could restart in 6-8 years after the end of the last event in 2010, hence in the period 2016-2018. Because cooling affects mainly the outer portions of the magmatic reservoir, pressurisation by cooling and crystallisation lead to the release of magma from the inner part of the reservoir with essentially constant composition, as observed at SHV over the last 20 years. REFERENCES Caricchi, L., Biggs, J., Annen, C., & Ebmeier, S. (2014). Earth and Planetary Science Letters, 388, 166-174. doi.org/10.1016/j.epsl.2013.12.002. Christopher, T. E., Blundy, J., Cashman, K., Cole, P., Edmonds, M., Smith, P. J., et al. (2015). Geochemistry Geophysics Geosystems, 16(9), 2797-2811. doi.org/10.1002/2015GC005791. Paulatto, M., Annen, C., Henstock, T. J., Kiddle, E., Minshull, T. A., Sparks, R. S. J., & Voight, B. (2012). Geochemistry Geophysics Geosystems, 13(1), doi.org/10.1029/2011GC003892. Tait, S., Jaupart, C., & Vergniolle, S. (1989). Earth and Planetary Science Letters, 92(1), 107-123. doi.org/10.1016/0012-821X(89)90025-3

  16. Occupational health and safety assessment of exposure to jet fuel combustion products in air medical transport.

    PubMed

    MacDonald, Russell D; Thomas, Laura; Rusk, Frederick C; Marques, Shauna D; McGuire, Dan

    2010-01-01

    Transport medicine personnel are potentially exposed to jet fuel combustion products. Setting-specific data are required to determine whether this poses a risk. This study assessed exposure to jet fuel combustion products, compared various engine ignition scenarios, and determined methods to minimize exposure. The Beechcraft King Air B200 turboprop aircraft equipped with twin turbine engines, using a kerosene-based jet fuel (Jet A-1), was used to measure products of combustion during boarding, engine startup, and flight in three separate engine start scenarios ("shielded": internal engine start, door closed; "exposed": ground power unit start, door open; and "minimized": ground power unit right engine start, door open). Real-time continuous monitoring equipment was used for oxygen, carbon dioxide, carbon monoxide, nitrogen dioxide, hydrogen sulfide, sulfur dioxide, volatile organic compounds, and particulate matter. Integrated methods were used for aldehydes, polycyclic aromatic hydrocarbons, volatile organic compounds, and aliphatic hydrocarbons. Samples were taken in the paramedic breathing zone for approximately 60 minutes, starting just before the paramedics boarded the aircraft. Data were compared against regulated time-weighted exposure thresholds to determine the presence of potentially harmful products of combustion. Polycyclic aromatic hydrocarbons, aldehydes, volatile organic compounds, and aliphatic hydrocarbons were found at very low concentrations or beneath the limits of detection. There were significant differences in exposures to particulates, carbon monoxide, and total volatile organic compound between the "exposed" and "minimized" scenarios. Elevated concentrations of carbon monoxide and total volatile organic compounds were present during the ground power unit-assisted dual-engine start. There were no appreciable exposures during the "minimized" or "shielded" scenarios. Air medical personnel exposures to jet fuel combustion products were generally low and did not exceed established U.S. or Canadian health and safety exposure limits. Avoidance of ground power unit-assisted dual-engine starts and closing the hangar door prior to start minimize or eliminate the occupational exposure.

  17. Preliminary Results on New Prototypes of Precision Rh-0.5at%Fe Resistance Thermometers of Chinese Production

    NASA Astrophysics Data System (ADS)

    Pavese, F.; Szmyrka-Grzebyk, A.; Lipinski, L.; Manuszkiewicz, H.; Qiu, Ping; Zhang, Jin Tao; Lin, Peng; Li, Xing Wei

    2008-02-01

    Given the practical impossibility of obtaining new precision Rh-0.5at%Fe resistance thermometers in recent years, the possible re-starting of the production of such thermometers in Yunnan (China) was explored by Istituto Nazionale di Ricerca Metrologica (INRIM). Ten prototypes of the new production were made available in early 2006. The paper reports the preliminary data from the testing performed to date on these prototypes at National Institute of Metrology (NIM) and Instytut Niskich Temperatur i Badan Strukturalnych (INTiBS). Although a problem with the alloy composition was detected, the reproducibility results on thermal cycling are very encouraging. Resistance-temperature ( R- T) characteristics below 30 K, though not identical with those of similar thermometers formerly available from Tinsley and VNIIFTRI, are still suitable for accurate metrology.

  18. [Nursing curriculum: where to start and restart].

    PubMed

    Vendrúscolo, D M; Manzolli, M C

    1996-01-01

    This study relies on the premise that all educational practices are based on presuppositions of philosophic and pedagogical nature, representing the curriculum, the vision of the world, perceived by the school and its professors. The leading question in this research can be formulated as: what is the professors perception on the guiding concepts of the nursing degree curriculum? 36 professors from 9 nursing schools in the State of São Paulo participated in the research answering enquiries based on the technique of Semantics Differential. The traditional, cognitive, behaviourist, self-realization and social reconstruction concepts guided this analysis. The results of the research expressed the subjects preference for postures of humanistic and social character, demonstrating the orientation for more renovating postures, as well as for more traditional postures, enabling the authors to conclude that there is no predominant guiding conception in the nursing curriculum.

  19. Hybrid Optimization Parallel Search PACKage

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    2009-11-10

    HOPSPACK is open source software for solving optimization problems without derivatives. Application problems may have a fully nonlinear objective function, bound constraints, and linear and nonlinear constraints. Problem variables may be continuous, integer-valued, or a mixture of both. The software provides a framework that supports any derivative-free type of solver algorithm. Through the framework, solvers request parallel function evaluation, which may use MPI (multiple machines) or multithreading (multiple processors/cores on one machine). The framework provides a Cache and Pending Cache of saved evaluations that reduces execution time and facilitates restarts. Solvers can dynamically create other algorithms to solve subproblems, amore » useful technique for handling multiple start points and integer-valued variables. HOPSPACK ships with the Generating Set Search (GSS) algorithm, developed at Sandia as part of the APPSPACK open source software project.« less

  20. A 15,000-hour cyclic endurance test of an 8-centimeter-diameter electron bombardment mercury ion thruster

    NASA Technical Reports Server (NTRS)

    Nakanishi, S.

    1976-01-01

    A laboratory model 8-cm thruster with improvements to minimize ion chamber erosion and peeling of sputtered metal was subjected to a cyclic endurance test for 15,040 hours and 460 restarts. A charted history of several thruster operating variables and off-normal events are shown in 600-hour segments at three points in the test. The transient behavior of these variables during a typical start-stop cycle is presented. Performance and operating characteristics were nearly constant throughout the test except for a change in the accelerator back-streaming limit. Findings of the post-test inspection confirmed most of the expected results. Charge-exchange ions caused normal accelerator grid erosion. The workability of the various design features have been substantiated, and attainable improvements in propellant utilization efficiency should significantly reduce accelerator erosion.

  1. Development of Ground Test System For RKX-200EB

    NASA Astrophysics Data System (ADS)

    Yudhi Irwanto, Herma

    2018-04-01

    After being postponed for seven years, the development of RKX-200EB now restarts by initiating a ground test, preceding the real flight test. The series of the development starts from simulation test using the real vehicle and its components, focusing on a flight sequence test using hardware in the loop simulation. The result of the simulation shows that the autonomous control system in development is able to control the X tail fin vehicle, since take off using booster, separating booster-sustainer, making flight maneuver using sustainer with average cruise speed of 1000 km/h, and doing bank to maneuver up to ±40 deg heading to the target. The simulation result also shows that the presence of sustainer in vehicle control can expand the distance range by 162% (12.6 km) from its ballistic range using only a booster.

  2. The Utility of Low-Dose Aripiprazole for the Treatment of Bipolar II and Bipolar NOS Depression.

    PubMed

    Kelly, Tammas; Lieberman, Daniel Z

    2017-02-01

    Despite initial reports of efficacy in bipolar depression, multicenter trials did not show aripiprazole to be better than placebo, possibly because the doses used were too high, leading to lower efficacy and high dropout rates. This study evaluated the effects of low-dose aripiprazole. Extensive clinical experience has suggested that doses beyond 5 mg are rarely efficacious. Data were gathered from patients with bipolar II or bipolar not otherwise specified depression using a retrospective chart review. Efficacy was assessed with the Clinical Global Impression-Improvement score. Patients who had at least 2 trials of aripiprazole were included in a retrospective off-on-off-on experimental design. All patients were on other medications when aripiprazole was started. Patients were treated with doses of 1 to 5 mg. On average, patients were rated improved or very much improved compared with baseline. Sixteen of 211 patients worsened or experienced no change. Forty-four patients (21%) discontinued due to adverse effects. The group of patients who underwent off-on-off-on trials experienced statistically significant improvement when they started and restarted aripiprazole, and statistically significant worsening when they discontinued it. When treating bipolar II or bipolar not otherwise specified depression, low doses of aripiprazole, 5 mg or less, may be more effective and better tolerated than higher ones. Clinicians should start treatment with a very low dose and give patients time to respond.

  3. Evaluation of a hybrid anaerobic biofilm reactor treating winery effluents and using grape stalks as biofilm carrier.

    PubMed

    Wahab, Mohamed Ali; Habouzit, Frédéric; Bernet, Nicolas; Jedidi, Naceur; Escudié, Renaud

    2016-01-01

    Wine production processes generate large amount of both winery wastewater and solid wastes. Furthermore, working periods, volumes and pollution loads greatly vary over the year. Therefore, it is recommended to develop a low-cost treatment technology for the treatment of winery effluents taking into account the variation of the organic loading rate (OLR). Accordingly, we have investigated the sequential operation of an anaerobic biofilm reactor treating winery effluents and using grape stalks (GSs) as biofilm carrier with an OLR ranging from 0.65 to 27 gCOD/L/d. The result showed that, during the start-up with wastewater influent, the chemical oxygen demand (COD) removal rate ranged from 83% to 93% and was about 91% at the end of the start-up period that lasted for 40 days. After 3 months of inactivity period of the reactor (no influent feeding), we have succeeded in restarting-up the reactor in only 15 days with a COD removal of 82% and a low concentration of volatile fatty acids (1 g/L), which confirms the robustness of the reactor. As a consequence, GSs can be used as an efficient carrier support, allowing a fast reactor start-up, while the biofilm conserves its activity during a non-feeding period. The proposed hybrid reactor thus permits to treat both winery effluents and GSs.

  4. 40 CFR 90.409 - Engine dynamometer test run.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...). (3) Record all pre-test data specified in § 90.405(c). (4) Start the test cycle (see § 90.410) within... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine dynamometer test run. 90.409... Test Procedures § 90.409 Engine dynamometer test run. (a) Engine and dynamometer start-up. (1) Only...

  5. 40 CFR 90.409 - Engine dynamometer test run.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...). (3) Record all pre-test data specified in § 90.405(c). (4) Start the test cycle (see § 90.410) within... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine dynamometer test run. 90.409... Test Procedures § 90.409 Engine dynamometer test run. (a) Engine and dynamometer start-up. (1) Only...

  6. 40 CFR 90.409 - Engine dynamometer test run.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...). (3) Record all pre-test data specified in § 90.405(c). (4) Start the test cycle (see § 90.410) within... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine dynamometer test run. 90.409... Test Procedures § 90.409 Engine dynamometer test run. (a) Engine and dynamometer start-up. (1) Only...

  7. 40 CFR 90.409 - Engine dynamometer test run.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...). (3) Record all pre-test data specified in § 90.405(c). (4) Start the test cycle (see § 90.410) within... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine dynamometer test run. 90.409... Test Procedures § 90.409 Engine dynamometer test run. (a) Engine and dynamometer start-up. (1) Only...

  8. 40 CFR 90.409 - Engine dynamometer test run.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...). (3) Record all pre-test data specified in § 90.405(c). (4) Start the test cycle (see § 90.410) within... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine dynamometer test run. 90.409... Test Procedures § 90.409 Engine dynamometer test run. (a) Engine and dynamometer start-up. (1) Only...

  9. Efficient Parallel Algorithms on Restartable Fail-Stop Processors

    DTIC Science & Technology

    1991-01-01

    resource (memory), and ( 3 ) that processors, memory and their interconnection must be The model of parallel computation known as the Par- perfectly...setting), arid ure an(I restart errors. We describe these arguments if] [AAtPS 871 (in a deterministic setting). Fault-tolerance Section 3 . of...grannmarity at the processor level --- for recent work on where Al is the nmber of failures during this step’s gate granilarities see [All 90, Pip 85

  10. Reactor operation environmental information document

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Haselow, J.S.; Price, V.; Stephenson, D.E.

    1989-12-01

    The Savannah River Site (SRS) produces nuclear materials, primarily plutonium and tritium, to meet the requirements of the Department of Defense. These products have been formed in nuclear reactors that were built during 1950--1955 at the SRS. K, L, and P reactors are three of five reactors that have been used in the past to produce the nuclear materials. All three of these reactors discontinued operation in 1988. Currently, intense efforts are being extended to prepare these three reactors for restart in a manner that protects human health and the environment. To document that restarting the reactors will have minimalmore » impacts to human health and the environment, a three-volume Reactor Operations Environmental Impact Document has been prepared. The document focuses on the impacts of restarting the K, L, and P reactors on both the SRS and surrounding areas. This volume discusses the geology, seismology, and subsurface hydrology. 195 refs., 101 figs., 16 tabs.« less

  11. Lithium overdose and delayed severe neurotoxicity: timing for renal replacement therapy and restarting of lithium.

    PubMed

    de Cates, Angharad N; Morlet, Julien; Antoun Reyad, Ayman; Tadros, George

    2017-10-25

    This is a case report of a man in his 60s who presented to an English hospital following a significant lithium overdose. He was monitored for 24 hours, and then renal replacement therapy was initiated after assessment by the renal team. As soon as the lithium level returned to normal therapeutic levels (from 4.7 mEq/L to 0.67 mEq/L), lithium was restarted by the medical team. At this point, the patient developed new slurred speech and later catatonia. In this case report, we discuss the factors that could determine which patients are at risk of neurotoxicity following lithium overdose and the appropriate decision regarding when and how to consider initiation of renal replacement therapy and restarting of lithium. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  12. 46 CFR 112.50-5 - Electric starting.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Electric starting. 112.50-5 Section 112.50-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-5 Electric starting...

  13. 46 CFR 112.50-5 - Electric starting.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Electric starting. 112.50-5 Section 112.50-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-5 Electric starting...

  14. 46 CFR 112.50-5 - Electric starting.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Electric starting. 112.50-5 Section 112.50-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-5 Electric starting...

  15. 46 CFR 112.50-5 - Electric starting.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Electric starting. 112.50-5 Section 112.50-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-5 Electric starting...

  16. 46 CFR 112.50-5 - Electric starting.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Electric starting. 112.50-5 Section 112.50-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-5 Electric starting...

  17. Drug fever and acute inflammation from hypercytokinemia triggered by dipeptidyl peptidase-4 inhibitor vildagliptin.

    PubMed

    Anno, Takatoshi; Kaneto, Hideaki; Kawasaki, Fumiko; Shigemoto, Ryo; Aoyama, Yumi; Kaku, Kohei; Okimoto, Niro

    2018-04-01

    A 69-year-old man started taking the dipeptidyl peptidase-4 inhibitor, vildagliptin. One week later, C-reactive protein and plasma immunoglobulin E levels were markedly elevated, and the vildagliptin was stopped. After the patient's laboratory findings were normalized, we decided to restart vildagliptin with the patient's agreement. The next day, he had a high fever, and C-reactive protein and procalcitonin levels were elevated. Although we failed to find a focus of infection, we started antibiotics therapy. Two days later, the high fever had improved, and the C-reactive protein level had decreased. A drug lymphocyte stimulation test showed a positive result for vildagliptin. We examined various kinds of cytokine and infection markers just before and after the treatment with vildagliptin. Finally, we diagnosed the patient with vildagliptin-induced drug fever, probably based on the increase of various inflammatory cytokine levels and the response to this. Taken together, we should be aware of the possibility of vildagliptin inducing drug fever and/or acute inflammation. © 2018 The Authors. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

  18. 76 FR 11940 - Airworthiness Directives; Turbomeca Model Arriel 1E2, 1S, and 1S1 Turboshaft Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-04

    ... discrepancies led to a ``one-off'' abnormal evolution of gas generator (NG) rating during engine starting. In... evolution of gas generator (NG) rating during engine starting. In one of these cases, this resulted in an...

  19. Design of automatic startup and shutdown logic for a Brayton-cycle 2- to 15-kilowatt engine

    NASA Technical Reports Server (NTRS)

    Vrancik, J. E.; Bainbridge, R. C.

    1975-01-01

    The NASA Lewis Research Center is conducting a closed-Brayton-cycle power conversion system technology program in which a complete power system (engine) has been designed and demonstrated. This report discusses the design of automatic startup and shutdown logic circuits as a modification to the control system presently used in this demonstration engine. This modification was primarily intended to make starting the engine as simple and safe as possible and to allow the engine to be run unattended. In the modified configuration the engine is started by turning the control console power on and pushing the start button after preheating the gas loop. No other operator action is required to effect a complete startup. Shutdown, if one is required, is also effected by a simple stop button. The automatic startup and shutdown of the engine have been successfully and purposefully demonstrated more than 50 times at the Lewis Research Center during 10,000 hours of unattended operation. The net effect of this modification is an engine that can be safely started and stopped by relatively untrained personnel. The approach lends itself directly to remote unattended operation.

  20. Plasma current start-up experiments without the central solenoid in the TST-2 spherical tokamak

    NASA Astrophysics Data System (ADS)

    Takase, Y.; Ejiri, A.; Shiraiwa, S.; Adachi, Y.; Ishii, N.; Kasahara, H.; Nuga, H.; Ono, Y.; Oosako, T.; Sasaki, M.; Shimada, Y.; Sumitomo, N.; Taguchi, I.; Tojo, H.; Tsujimura, J.; Ushigome, M.; Yamada, T.; Hanada, K.; Hasegawa, M.; Idei, H.; Nakamura, K.; Sakamoto, M.; Sasaki, K.; Sato, K. N.; Zushi, H.; Nishino, N.; Mitarai, O.

    2006-08-01

    Several techniques for initiating the plasma current without the use of the central solenoid are being developed in TST-2. While TST-2 was temporarily located at Kyushu University, two types of start-up scenarios were demonstrated. (1) A plasma current of 4 kA was generated and sustained for 0.28 s by either electron cyclotron wave or electron Bernstein wave, without induction. (2) A plasma current of 10 kA was obtained transiently by induction using only outboard poloidal field coils. In the second scenario, it is important to supply sufficient power for ionization (100 kW of EC power was sufficient in this case), since the vertical field during start-up is not adequate to maintain plasma equilibrium. In addition, electron heating experiments using the X-B mode conversion scenario were performed, and a heating efficiency of 60% was observed at a 100 kW RF power level. TST-2 is now located at the Kashiwa Campus of the University of Tokyo. Significant upgrades were made in both magnetic coil power supplies and RF systems, and plasma experiments have restarted. RF power of up to 400 kW is available in the high-harmonic fast wave frequency range around 20 MHz. Four 200 MHz transmitters are now being prepared for plasma current start-up experiments using RF power in the lower-hybrid frequency range. Preparations are in progress for a new plasma merging experiment (UTST) aimed at the formation and sustainment of ultra-high β ST plasmas.

  1. Superphenix: Restarting, with emphasis on research

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    1994-04-01

    French Prime Minister Edouard Baladour announced on February 22 that the Superphenix fast reactor at Creys-Malville will be allowed to restart. Along with his industry minister, Gerard Longuet, and the environment minister, Michel Bamier, Baladour has accepted the recommendation for reissuance of an operating license submitted to the ministers in January by the nuclear installations safety directorate (DSIN). In announcing their approval for restart, the ministers emphasized that the reactor was to be used as a research and demonstration facility rather than a power station. In particular, they said it should be used to investigate the possibility of using fastmore » reactors as plutonium burners rather than breeders and for the incineration of other long-lived actinide wastes. This point was made also by DSIN Director Andre-Claude Lacoste in his recommendations, but appears to have been given more weight by the government ministers. The ministers also accepted the DSIN recommendation that restart be conditional on completion of improvements to fire protection systems for the secondary sodium coolant ducts. Baladour said that it would take several months to complete this work, but other sources have suggested that the reactor could be ready to operate this month. DSIN has also stipulated that the power level be limited for several months to around 50 percent of the plant`s 1200-MWe potential in order to check out all the systems carefully.« less

  2. Journal of Engineering Thermophysics (Selected Articles),

    DTIC Science & Technology

    1983-05-13

    compressor, prediction of unsteady vibration , and prevention of unsteady vibration . This test was undergone on a turbojet engine. The paper stresses the...induce unsteady engine vibration . While studying the effect of inlet anomaly and variation of the first stage nozzle area of the turbine, the engine...constant revolution speed curve until unsteady vibration or stall appeared. In studying the influence of the starting sequence, starting was

  3. Program Correctness, Verification and Testing for Exascale (Corvette)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sen, Koushik; Iancu, Costin; Demmel, James W

    The goal of this project is to provide tools to assess the correctness of parallel programs written using hybrid parallelism. There is a dire lack of both theoretical and engineering know-how in the area of finding bugs in hybrid or large scale parallel programs, which our research aims to change. In the project we have demonstrated novel approaches in several areas: 1. Low overhead automated and precise detection of concurrency bugs at scale. 2. Using low overhead bug detection tools to guide speculative program transformations for performance. 3. Techniques to reduce the concurrency required to reproduce a bug using partialmore » program restart/replay. 4. Techniques to provide reproducible execution of floating point programs. 5. Techniques for tuning the floating point precision used in codes.« less

  4. Economic evaluation of strategies for restarting anticoagulation therapy after a first event of unprovoked venous thromboembolism.

    PubMed

    Monahan, M; Ensor, J; Moore, D; Fitzmaurice, D; Jowett, S

    2017-08-01

    Essentials Correct duration of treatment after a first unprovoked venous thromboembolism (VTE) is unknown. We assessed when restarting anticoagulation was worthwhile based on patient risk of recurrent VTE. When the risk over a one-year period is 17.5%, restarting is cost-effective. However, sensitivity analyses indicate large uncertainty in the estimates. Background Following at least 3 months of anticoagulation therapy after a first unprovoked venous thromboembolism (VTE), there is uncertainty about the duration of therapy. Further anticoagulation therapy reduces the risk of having a potentially fatal recurrent VTE but at the expense of a higher risk of bleeding, which can also be fatal. Objective An economic evaluation sought to estimate the long-term cost-effectiveness of using a decision rule for restarting anticoagulation therapy vs. no extension of therapy in patients based on their risk of a further unprovoked VTE. Methods A Markov patient-level simulation model was developed, which adopted a lifetime time horizon with monthly time cycles and was from a UK National Health Service (NHS)/Personal Social Services (PSS) perspective. Results Base-case model results suggest that treating patients with a predicted 1 year VTE risk of 17.5% or higher may be cost-effective if decision makers are willing to pay up to £20 000 per quality adjusted life year (QALY) gained. However, probabilistic sensitivity analysis shows that the model was highly sensitive to overall parameter uncertainty and caution is warranted in selecting the optimal decision rule on cost-effectiveness grounds. Univariate sensitivity analyses indicate variables such as anticoagulation therapy disutility and mortality risks were very influential in driving model results. Conclusion This represents the first economic model to consider the use of a decision rule for restarting therapy for unprovoked VTE patients. Better data are required to predict long-term bleeding risks during therapy in this patient group. © 2017 International Society on Thrombosis and Haemostasis.

  5. Extreme High and Low Temperature Operation of the Silicon-On-Insulator Type CHT-OPA Operational Amplifier

    NASA Technical Reports Server (NTRS)

    Patterson, Richard; Hammoud, Ahmad; Elbuluk, Malik

    2008-01-01

    A new operational amplifier chip based on silicon-on-insulator technology was evaluated for potential use in extreme temperature environments. The CHT-OPA device is a low power, precision operational amplifier with rail-to-rail output swing capability, and it is rated for operation between -55 C and +225 C. A unity gain inverting circuit was constructed utilizing the CHT-OPA chip and a few passive components. The circuit was evaluated in the temperature range from -190 C to +200 C in terms of signal gain and phase shift, and supply current. The investigations were carried out to determine suitability of this device for use in space exploration missions and aeronautic applications under wide temperature incursion. Re-restart capability at extreme temperatures, i.e. power switched on while the device was soaked at extreme temperatures, was also investigated. In addition, the effects of thermal cycling under a wide temperature range on the operation of this high performance amplifier were determined. The results from this work indicate that this silicon-on-insulator amplifier chip maintained very good operation between +200 C and -190 C. The limited thermal cycling had no effect on the performance of the amplifier, and it was able to re-start at both -190 C and +200 C. In addition, no physical degradation or packaging damage was introduced due to either extreme temperature exposure or thermal cycling. The good performance demonstrated by this silicon-on-insulator operational amplifier renders it a potential candidate for use in space exploration missions or other environments under extreme temperatures. Additional and more comprehensive characterization is, however, required to establish the reliability and suitability of such devices for long term use in extreme temperature applications.

  6. Persistence to disease-modifying therapies for multiple sclerosis in a Canadian cohort

    PubMed Central

    Melesse, Dessalegn Y; Marrie, Ruth Ann; Blanchard, James F; Yu, Bo Nancy; Evans, Charity

    2017-01-01

    Purpose To examine the long-term persistence to the first-line injectable disease-modifying therapies (DMTs) for multiple sclerosis (MS) and to identify the factors associated with nonpersistence. Patients and methods We used population-based administrative data from Manitoba, Canada. All adult subjects who were diagnosed with MS and dispensed a first-line injectable DMT (beta-interferon-1b, beta-interferon-1a, and glatiramer acetate) between 1996 and 2011 and had a minimum of 1 year of follow-up were included. The primary outcome was the median time to discontinuation of any DMT. The associations between potential predictors and persistence were estimated using multivariable Cox-proportional hazard models. Results Overall, 721 subjects were followed for a median of 7.8 years (interquartile range 6.1). The median time to discontinuation of all first-line DMTs was 4.2 years (25th and 75th percentile: 1.7, 10.6 years). Of the 451 (62.6%) subjects who discontinued their DMT during the study period, 259 (57.4%) eventually resumed or restarted a DMT. Subjects who were younger when starting a DMT, had prior MS-related hospitalizations, were more recently diagnosed with MS, or had a greater lag time between their MS diagnosis and DMT initiation were more likely to discontinue therapy. Conclusion Over half of the individuals receiving a DMT for MS in Manitoba remained on therapy for at least 4 years. DMT discontinuation occurred in 60% of the cohort, but most restarted a DMT within 1 year. While not all of the factors identified with discontinuing DMT are modifiable, they may help practitioners enhance MS care by identifying individuals who may be at particular risk for DMT discontinuation. PMID:28721023

  7. Reconstruction for limited-projection fluorescence molecular tomography based on projected restarted conjugate gradient normal residual.

    PubMed

    Cao, Xu; Zhang, Bin; Liu, Fei; Wang, Xin; Bai, Jing

    2011-12-01

    Limited-projection fluorescence molecular tomography (FMT) can greatly reduce the acquisition time, which is suitable for resolving fast biology processes in vivo but suffers from severe ill-posedness because of the reconstruction using only limited projections. To overcome the severe ill-posedness, we report a reconstruction method based on the projected restarted conjugate gradient normal residual. The reconstruction results of two phantom experiments demonstrate that the proposed method is feasible for limited-projection FMT. © 2011 Optical Society of America

  8. Zero energy-storage ballast for compact fluorescent lamps

    DOEpatents

    Schultz, W.N.; Thomas, R.J.

    1999-08-31

    A CFL ballast includes complementary-type switching devices connected in series with their gates connected together at a control node. The switching devices supply a resonant tank circuit which is tuned to a frequency near, but slightly lower than, the resonant frequency of a resonant control circuit. As a result, the tank circuit restarts oscillations immediately following each zero crossing of the bus voltage. Such rapid restarts avoid undesirable flickering while maintaining the operational advantages and high efficacy of the CFL ballast. 4 figs.

  9. Zero energy-storage ballast for compact fluorescent lamps

    DOEpatents

    Schultz, William Newell; Thomas, Robert James

    1999-01-01

    A CFL ballast includes complementary-type switching devices connected in series with their gates connected together at a control node. The switching devices supply a resonant tank circuit which is tuned to a frequency near, but slightly lower than, the resonant frequency of a resonant control circuit. As a result, the tank circuit restarts oscillations immediately following each zero crossing of the bus voltage. Such rapid restarts avoid undesirable flickering while maintaining the operational advantages and high efficacy of the CFL ballast.

  10. Laser Mode Behavior of the Cassini CIRS Fourier Transform Spectrometer at Saturn

    NASA Technical Reports Server (NTRS)

    Brasunas, John C.

    2012-01-01

    The CIRS Fourier transform spectrometer aboard the NASA/ESA/ASI Cassini orbiter has been acquiring spectra of the Saturnian system since 2004. The CIRS reference interferometer employs a laser diode to trigger the interferogram sampling. Although the control of laser diode drive current and operating temperature are stringent enough to restrict laser wavelength variation to a small fraction of CIRS finest resolution element, the CIRS instrument does need to be restarted every year or two, at which time it may start in a new laser mode. By monitoring the Mylar absorption features in uncalibrated spectra due to the beam splitter Mylar substrate, it can be shown that these jumps are to adjacent modes and that most of the eight-year operation so far is restricted to three adjacent modes. For a given mode, the wavelength stability appears consistent with the stability of the laser diode drive curren.t and operating temperature.

  11. Rate and rhythm control strategies for apraxia of speech in nonfluent primary progressive aphasia.

    PubMed

    Beber, Bárbara Costa; Berbert, Monalise Costa Batista; Grawer, Ruth Siqueira; Cardoso, Maria Cristina de Almeida Freitas

    2018-01-01

    The nonfluent/agrammatic variant of primary progressive aphasia is characterized by apraxia of speech and agrammatism. Apraxia of speech limits patients' communication due to slow speaking rate, sound substitutions, articulatory groping, false starts and restarts, segmentation of syllables, and increased difficulty with increasing utterance length. Speech and language therapy is known to benefit individuals with apraxia of speech due to stroke, but little is known about its effects in primary progressive aphasia. This is a case report of a 72-year-old, illiterate housewife, who was diagnosed with nonfluent primary progressive aphasia and received speech and language therapy for apraxia of speech. Rate and rhythm control strategies for apraxia of speech were trained to improve initiation of speech. We discuss the importance of these strategies to alleviate apraxia of speech in this condition and the future perspectives in the area.

  12. Geomagnetic reversal rates following Palaeozoic superchrons have a fast restart mechanism.

    PubMed

    Hounslow, Mark W

    2016-08-30

    Long intervals of single geomagnetic polarity (superchrons) reflect geodynamo processes, driven by core-mantle boundary interactions; however, it is not clear what initiates the start and end of superchrons, other than superchrons probably reflect lower heat flow across the core-mantle boundary compared with adjacent intervals. Here geomagnetic polarity timescales, with confidence intervals, are constructed before and following the reverse polarity Kiaman (Carboniferous-Permian) and Moyero (Ordovician) superchrons, providing a window into the geodynamo processes. Similar to the Cretaceous, asymmetry in reversal rates is seen in the Palaeozoic superchrons, but the higher reversal rates imply higher heatflow thresholds for entering the superchron state. Similar to the Cretaceous superchron, unusually long-duration chrons characterize the ∼10 Myr interval adjacent to the superchrons, indicating a transitional reversing state to the superchrons. This may relate to a weak pattern in the clustering of chron durations superimposed on the dominant random arrangement of chron durations.

  13. Geomagnetic reversal rates following Palaeozoic superchrons have a fast restart mechanism

    PubMed Central

    Hounslow, Mark W.

    2016-01-01

    Long intervals of single geomagnetic polarity (superchrons) reflect geodynamo processes, driven by core–mantle boundary interactions; however, it is not clear what initiates the start and end of superchrons, other than superchrons probably reflect lower heat flow across the core–mantle boundary compared with adjacent intervals. Here geomagnetic polarity timescales, with confidence intervals, are constructed before and following the reverse polarity Kiaman (Carboniferous–Permian) and Moyero (Ordovician) superchrons, providing a window into the geodynamo processes. Similar to the Cretaceous, asymmetry in reversal rates is seen in the Palaeozoic superchrons, but the higher reversal rates imply higher heatflow thresholds for entering the superchron state. Similar to the Cretaceous superchron, unusually long-duration chrons characterize the ∼10 Myr interval adjacent to the superchrons, indicating a transitional reversing state to the superchrons. This may relate to a weak pattern in the clustering of chron durations superimposed on the dominant random arrangement of chron durations. PMID:27572303

  14. Theoretical and software considerations for general dynamic analysis using multilevel substructured models

    NASA Technical Reports Server (NTRS)

    Schmidt, R. J.; Dodds, R. H., Jr.

    1985-01-01

    The dynamic analysis of complex structural systems using the finite element method and multilevel substructured models is presented. The fixed-interface method is selected for substructure reduction because of its efficiency, accuracy, and adaptability to restart and reanalysis. This method is extended to reduction of substructures which are themselves composed of reduced substructures. The implementation and performance of the method in a general purpose software system is emphasized. Solution algorithms consistent with the chosen data structures are presented. It is demonstrated that successful finite element software requires the use of software executives to supplement the algorithmic language. The complexity of the implementation of restart and reanalysis porcedures illustrates the need for executive systems to support the noncomputational aspects of the software. It is shown that significant computational efficiencies can be achieved through proper use of substructuring and reduction technbiques without sacrificing solution accuracy. The restart and reanalysis capabilities and the flexible procedures for multilevel substructured modeling gives economical yet accurate analyses of complex structural systems.

  15. On factoring RSA modulus using random-restart hill-climbing algorithm and Pollard’s rho algorithm

    NASA Astrophysics Data System (ADS)

    Budiman, M. A.; Rachmawati, D.

    2017-12-01

    The security of the widely-used RSA public key cryptography algorithm depends on the difficulty of factoring a big integer into two large prime numbers. For many years, the integer factorization problem has been intensively and extensively studied in the field of number theory. As a result, a lot of deterministic algorithms such as Euler’s algorithm, Kraitchik’s, and variants of Pollard’s algorithms have been researched comprehensively. Our study takes a rather uncommon approach: rather than making use of intensive number theories, we attempt to factorize RSA modulus n by using random-restart hill-climbing algorithm, which belongs the class of metaheuristic algorithms. The factorization time of RSA moduli with different lengths is recorded and compared with the factorization time of Pollard’s rho algorithm, which is a deterministic algorithm. Our experimental results indicates that while random-restart hill-climbing algorithm is an acceptable candidate to factorize smaller RSA moduli, the factorization speed is much slower than that of Pollard’s rho algorithm.

  16. Visualization of the freeze/thaw characteristics of a copper/water heat pipe - Effects of non-condensible gas

    NASA Technical Reports Server (NTRS)

    Ochterbeck, J. M.; Peterson, G. P.

    1991-01-01

    The freeze/thaw characteristics of a copper/water heat pipe of rectangular cross section were investigated experimentally to determine the effect of variations in the amount of non-condensible gases (NCG) present. The transient internal temperature profiles in both the liquid and vapor channels are presented along with contours of the frozen fluid configuration obtained through visual observation. Several interesting phenomena were observed including total blockage of the vapor channel by a solid plug, evaporator dryout during restart, and freezing blowby. In addition, the restart characteristics are shown to be strongly dependent upon the shutdown procedure used prior to freezing, indicating that accurate prediction of the startup or restart characteristics requires a complete thermal history. Finally, the experimental results indicate that the freeze/thaw characteristics of room temperature heat pipes may be significantly different from those occurring in higher temperature, liquid metal heat pipes due to differences in the vapor pressures in the frozen condition.

  17. HLW system plan - revision 2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    1994-01-14

    The projected ability of the Tank Farm to support DWPF startup and continued operation has diminished somewhat since revision 1 of this Plan. The 13 month delay in DWPF startup, which actually helps the Tank Farm condition in the near term, was more than offset by the 9 month delay in ITP startup, the delay in the Evaporator startups and the reduction to Waste Removal funding. This Plan does, however, describe a viable operating strategy for the success of the HLW System and Mission, albeit with less contingency and operating flexibility than in the past. HLWM has focused resources frommore » within the division on five near term programs: The three evaporator restarts, DWPF melter heatup and completion of the ITP outage. The 1H Evaporator was restarted 12/28/93 after a 9 month shutdown for an extensive Conduct of Operations upgrade. The 2F and 2H Evaporators are scheduled to restart 3/94 and 4/94, respectively. The RHLWE startup remains 11/17/97.« less

  18. Substrate reactivity as a function of the extent of reaction in the enzymatic hydrolysis of lignocellulose

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Desai, S.G.; Converse, A.O.

    1997-12-20

    In an effort to better understand the role of the substrate in the rapid fall off in the rate of enzymatic hydrolysis of cellulose with conversion, substrate reactivity was measured as a function of conversion. These measurements were made by interrupting the hydrolysis of pretreated wood at various degrees of conversion; and, after boiling and washing, restarting the hydrolysis in fresh butter with fresh enzyme. The comparison of the restart rate per enzyme adsorbed with the initial rate per enzyme adsorbed, both extrapolated back to zero conversion, provides a measurement of the substrate reactivity without the complications of product inhibitionmore » or cellulase inactivation. The results indicate that the substrate reactivity falls only modestly as conversion increases. However, the restart rate is still higher than the rate of the uninterrupted hydrolysis, particularly at high conversion. Hence the authors conclude that the loss of substrate reactivity is not the principal cause for the long residence time required for complete conversion.« less

  19. Conversion of a micro, glow-ignition, two-stroke engine from nitromethane-methanol blend fuel to military jet propellant (JP-8)

    NASA Astrophysics Data System (ADS)

    Wiegand, Andrew L.

    The goal of the thesis "Conversion of a Micro, Glow-Ignition, Two-Stroke Engine from Nitromethane-Methanol Blend Fuel to Military Jet Propellant (JP-8)" was to demonstrate the ability to operate a small engine on JP-8 and was completed in two phases. The first phase included choosing, developing a test stand for, and baseline testing a nitromethane-methanol-fueled engine. The chosen engine was an 11.5 cc, glow-ignition, two-stroke engine designed for remote-controlled helicopters. A micro engine test stand was developed to load and motor the engine. Instrumentation specific to the low flow rates and high speeds of the micro engine was developed and used to document engine behavior. The second phase included converting the engine to operate on JP-8, completing JP-8-fueled steady-state testing, and comparing the performance of the JP-8-fueled engine to the nitromethane-methanol-fueled engine. The conversion was accomplished through a novel crankcase heating method; by heating the crankcase for an extended period of time, a flammable fuel-air mixture was generated in the crankcase scavenged engine, which greatly improved starting times. To aid in starting and steady-state operation, yttrium-zirconia impregnated resin (i.e. ceramic coating) was applied to the combustion surfaces. This also improved the starting times of the JP-8-fueled engine and ultimately allowed for a 34-second starting time. Finally, the steady-state data from both the nitromethane-methanol and JP-8-fueled micro engine were compared. The JP-8-fueled engine showed signs of increased engine friction while having higher indicated fuel conversion efficiency and a higher overall system efficiency. The minimal ability of JP-8 to cool the engine via evaporative effects, however, created the necessity of increased cooling air flow. The conclusion reached was that JP-8-fueled micro engines could be viable in application, but not without additional research being conducted on combustion phenomenon and cooling requirements.

  20. Resistance of Metallic Screens in a Cryogenic Flow

    NASA Astrophysics Data System (ADS)

    Fischer, Alexander; Stief, Malte

    The propellant behaviour in cryogenic upper stages tanks imposes challenging requirements on the design, especially for future upper stages designed for multiple restarts and long ballistic flight phases. The main challenge is the supply of the propellants to the feed system prior to the engine reignition. During the entire mission the engine requires a gaseous and bubble free liquid supply of propellant at the required thermodynamic conditions. The current research focus is to prepare the initial steps for the maturation of the Propellant Management Device (PMD) technology for cryogenic tank systems. Main components of such a PMD are metallic screens. The metallic screens are used as barrier for any gas bubbles within the fluid stream approaching the space craft engines. The screen characteristics are of fundamental importance for the PMD and feed system design. The paper presents a summary on available experimental screen data with regard to the flow resistance and gives a comparison with theoretical and empirical predictions found in literature. The lack on comparable data with regard to space craft applications and the need on further research with cryogenic flows is demonstrated. The DLR Institute of Space Systems is preparing various cryogenic tests to collect the desired information about the flow properties of such metallic screens. The planned test setup and the foreseen experiments will be presented.

  1. Plasma-enhanced mixing and flameholding in supersonic flow.

    PubMed

    Firsov, Alexander; Savelkin, Konstantin V; Yarantsev, Dmitry A; Leonov, Sergey B

    2015-08-13

    The results of experimental study of plasma-based mixing, ignition and flameholding in a supersonic model combustor are presented in the paper. The model combustor has a length of 600 mm and cross section of 72 mm width and 60 mm height. The fuel is directly injected into supersonic airflow (Mach number M=2, static pressure P(st)=160-250 Torr) through wall orifices. Two series of tests are focused on flameholding and mixing correspondingly. In the first series, the near-surface quasi-DC electrical discharge is generated by flush-mounted electrodes at electrical power deposition of W(pl)=3-24 kW. The scope includes parametric study of ignition and flame front dynamics, and comparison of three schemes of plasma generation: the first and the second layouts examine the location of plasma generators upstream and downstream from the fuel injectors. The third pattern follows a novel approach of combined mixing/ignition technique, where the electrical discharge distributes along the fuel jet. The last pattern demonstrates a significant advantage in terms of flameholding limit. In the second series of tests, a long discharge of submicrosecond duration is generated across the flow and along the fuel jet. A gasdynamic instability of thermal cavity developed after a deposition of high-power density in a thin plasma filament promotes the air-fuel mixing. The technique studied in this work has weighty potential for high-speed combustion applications, including cold start/restart of scramjet engines and support of transition regime in dual-mode scramjet and at off-design operation. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  2. Procedure Training Aid for the SH-3D/H Normal Start Checklist.

    DTIC Science & Technology

    1982-02-01

    1 Engine .... START Pupoe: To make a Normal Start of No. 1 engine. :4 14. Action Pilot/Copilot verify lite -off by noting rapid rise in T5 and Nq and...Nf increasinq 15. Note Normal starts are characterized by 7 0-75D0 T5 in I seconds after lite -off 16. If T5 is incrasinn too rapidlyv or appears to...Pumps 206 NORMAL START CHECKLIST ITEM NO. 23. No. I Ergine ... TART 14. Action Pilot/Copilot verify lite -off by noting ra ’pid rise in and Ng and Nf

  3. Case Study of a Discontinued Start-Up Engineering Program: Critical Challenges and Lessons Learned

    ERIC Educational Resources Information Center

    Friess, Wilhelm A.

    2017-01-01

    The explanatory case study presented here analyzes the factors that have contributed to the failure of a start-up engineering program launched at an off-campus site, and aimed at imparting the first two years of the BSc Mechanical, Electrical, Computer and Civil Engineering utilizing an integrated curriculum. Findings indicate the root cause for…

  4. Method and apparatus for selectively controlling the speed of an engine

    DOEpatents

    Davis, Roy Inge

    2001-02-27

    A control assembly 12 for use within a vehicle 10 having an engine 14 and which selectively controls the speed of the engine 14 in order to increase fuel efficiency and to effect relatively smooth starting and stopping of the engine. Particularly, in one embodiment, control assembly 12 cooperatively operates with a starter/alternator assembly 20 and is adapted for use with hybrid vehicles employing a start/stop powertrain assembly, wherein fuel efficiency is increased by selectively stopping engine operation when the vehicle has stopped.

  5. NASA automatic system for computer program documentation, volume 2

    NASA Technical Reports Server (NTRS)

    Simmons, D. B.

    1972-01-01

    The DYNASOR 2 program is used for the dynamic nonlinear analysis of shells of revolution. The equations of motion of the shell are solved using Houbolt's numerical procedure. The displacements and stress resultants are determined for both symmetrical and asymmetrical loading conditions. Asymmetrical dynamic buckling can be investigated. Solutions can be obtained for highly nonlinear problems utilizing as many as five of the harmonics generated by SAMMSOR program. A restart capability allows the user to restart the program at a specified time. For Vol. 1, see N73-22129.

  6. Startup of a frozen heat pipe in one-g and micro-g environments - A proposed shuttle flight experiment

    NASA Technical Reports Server (NTRS)

    Ochterbeck, J. M.; Peterson, G. P.

    1991-01-01

    An attempt is made to determine how a heat pipe freezes under various low load and/or no load conditions in both one-g and micro-g environments. Also of interest are the mechanisms that can be used to restart the heat pipe after freezing has occurred. Particular attention is given to step function power reductions and the resulting distribution of the working fluid after freezing has occurred and the effect of noncondensible gases on the frozen configuration and the restart characteristics.

  7. A Microprocessor Development System for the ALTOS Series Microcomputers.

    DTIC Science & Technology

    1981-06-01

    location, and 3) routines for online user self-help and system use instructions. The primary ccnsideration in the desin of the HOST control program was...TO LOWER CASE CPI ;rYNAMIC SET ITEMIZE JZ MAKEI CPI Vt" ;LYNAMIC SET TOTAL ONLY JZ MAKET CPI "e JNZ STACKIT ;RESTART TEST IF NOT E MEM55 LXI HMEMM...RESET STACK JMP MEM0I ;RESTART TEST MAKEI MVI All ;MAKE ITEMIZE STA MEMP CALL BSOUT RET MAKET MJI A,O ;MAKE TOTAL ONLY STA MEMP CALL BSOUT RET * LONE WITH

  8. Optimization of new magnetorheological fluid mount for vibration control of start/stop engine mode

    NASA Astrophysics Data System (ADS)

    Chung, Jye Ung; Phu, Do Xuan; Choi, Seung-Bok

    2015-04-01

    The technologies related to saving energy/or green vehicles are actively researched. In this tendency, the problem for reducing exhausted gas is in development with various ways. Those efforts are directly related to the operation of engine which emits exhausted gas. The auto start/stop of vehicle engine when a vehicle stop at road is currently as a main stream of vehicle industry resulting in reducing exhausted gas. However, this technology automatically turns on and off engine frequently. This motion induces vehicle engine to transmit vibration of engine which has large displacement, and torsional impact to chassis. These vibrations causing uncomfortable feeling to passengers are transmitted through the steering wheel and the gear knob. In this work, in order to resolve this vibration issue, a new proposed magnetorheological (MR) fluid based engine mount (MR mount in short) is presented. The proposed MR mount is designed to satisfy large damping force in various frequency ranges. It is shown that the proposed mount can have large damping force and large force ratio which is enough to control unwanted vibrations of engine start/stop mode.

  9. Starting characteristics and combustion performance of magnesium slurry in 6.5-inch-diameter ram-jet engine mounted in connected-pipe facility

    NASA Technical Reports Server (NTRS)

    Gibbs, James B

    1954-01-01

    The starting characteristics and combustion performance of slurry type fuels, consisting of 50 percent magnesium powder in a hydrocarbon carrier, have been investigated in a flight-type, 6.5-inch-diameter ram-jet engine in a connected-pipe facility. Quick, dependable starting of the engine was obtained by the use of a disk which blocked part of the combustor area downstream of the flame holder. Acceptable performance was achieved with a short fuel-air mixing length by the development of a fuel-distribution control sleeve.

  10. Assessment of lymphatic filariasis prior to re-starting mass drug administration campaigns in coastal Kenya.

    PubMed

    Njenga, Sammy M; Kanyi, Henry M; Mutungi, Faith M; Okoyo, Collins; Matendechero, Hadley S; Pullan, Rachel L; Halliday, Katherine E; Brooker, Simon J; Wamae, C Njeri; Onsongo, Joyce K; Won, Kimberly Y

    2017-02-22

    Lymphatic filariasis (LF) is a debilitating disease associated with extensive disfigurement and is one of a diverse group of diseases referred to as neglected tropical diseases (NTDs) which mainly occur among the poorest populations. In line with global recommendations to eliminate LF, Kenya launched its LF elimination programme in 2002 with the aim to implement annual mass drug administration (MDA) in order to interrupt LF transmission. However, the programme faced financial and administrative challenges over the years such that sustained annual MDA was not possible. Recently, there has been renewed interest to eliminate LF and the Kenyan Ministry of Health, through support from World Health Organization (WHO), restarted annual MDA in 2015. The objective of this study was to evaluate the current status of LF infection in the endemic coastal region of Kenya before MDA campaigns were restarted. Ten sentinel sites in Kwale, Kilifi, Tana River, Lamu, and Taita-Taveta counties in coastal Kenya were selected for participation in a cross-sectional survey of LF infection prevalence. At least 300 individuals in each sentinel village were sampled through random house-to-house visits. During the day, the point-of-care immunochromatographic test (ICT) was used to detect the presence of Wuchereria bancrofti circulating filarial antigen in finger prick blood samples collected from residents of the selected sentinel villages. Those individuals who tested positive with the ICT test were requested to provide a night-time blood sample for microfilariae (MF) examination. The overall prevalence of filarial antigenaemia was 1.3% (95% CI: 0.9-1.8%). Ndau Island in Lamu County had the highest prevalence (6.3%; 95% CI: 4.1-9.7%), whereas sites in Kilifi and Kwale counties had prevalences < 1.7%. Mean microfilarial density was also higher in Ndau Island (234 MF/ml) compared to sentinel sites in Kwale and Kilifi counties (< 25 MF/ml). No LF infection was detected in Tana River and Taita-Taveta counties. Overall, more than 88% of the study participants reported to have used a bed net the previous night. Prevalence of LF infection is generally very low in coastal Kenya, but there remain areas that require further rounds of MDA if the disease is to be eliminated as a public health problem in line with the ongoing global elimination efforts. However, areas where there was no evidence of LF transmission should be considered for WHO-recommended transmission assessment surveys in view of stopping MDA.

  11. Recent Activities of the Physical Society of Japan for the Promotion of Gender Equality (abstract)

    NASA Astrophysics Data System (ADS)

    Maeda, Atsutaka; Yonenaga, Ichiro; Tajima, Setsuko; Hiyama, Emiko; Torikai, Eiko

    2009-04-01

    We present activities of the Gender Equality Promotion Committee of the Physical Society of Japan (JPS) untaken after the Second IUPAP Women in Physics Conference, Rio de Janiero, 2005. These include: (1) summer and spring classes for high school girls, (2) symposia on the promotion of gender equality at annual JPS meetings, (3) continuous cooperation with the Japan Inter-Society Liaison Association Committee for Promoting Equal Participation of Men and Women in Science and Engineering (EPMEWSE), (4) consultation for JPS members on the Restart Postdoctoral Fellowship (RPD) program conducted by the Japan Society for the Promotion of Science (JSPS), (5) publication of a series of articles in the JPS membership journal, and (6) presentation at international meetings such as the Asia Pacific Physics Conference 10 (APPC10). We report that these activities were successful.

  12. MOOSE IPL Extensions (Control Logic)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Permann, Cody

    In FY-2015, the development of MOOSE was driven by the needs of the NEAMS MOOSE-based applications, BISON, MARMOT, and RELAP-7. An emphasis was placed on the continued upkeep and improvement MOOSE in support of the product line integration goals. New unified documentation tools have been developed, several improvements to regression testing have been enforced and overall better software quality practices have been implemented. In addition the Multiapps and Transfers systems have seen significant refactoring and robustness improvements, as has the “Restart and Recover” system in support of Multiapp simulations. Finally, a completely new “Control Logic” system has been engineered tomore » replace the prototype system currently in use in the RELAP-7 code. The development of this system continues and is expected to handle existing needs as well as support future enhancements.« less

  13. Combustion Stability Characteristics of the Project Morpheus Liquid Oxygen / Liquid Methane Main Engine

    NASA Technical Reports Server (NTRS)

    Melcher, John C.; Morehead, Robert L.

    2014-01-01

    The project Morpheus liquid oxygen (LOX) / liquid methane (LCH4) main engine is a Johnson Space Center (JSC) designed 5,000 lbf-thrust, 4:1 throttling, pressure-fed cryogenic engine using an impinging element injector design. The engine met or exceeded all performance requirements without experiencing any in- ight failures, but the engine exhibited acoustic-coupled combustion instabilities during sea-level ground-based testing. First tangential (1T), rst radial (1R), 1T1R, and higher order modes were triggered by conditions during the Morpheus vehicle derived low chamber pressure startup sequence. The instability was never observed to initiate during mainstage, even at low power levels. Ground-interaction acoustics aggravated the instability in vehicle tests. Analysis of more than 200 hot re tests on the Morpheus vehicle and Stennis Space Center (SSC) test stand showed a relationship between ignition stability and injector/chamber pressure. The instability had the distinct characteristic of initiating at high relative injection pressure drop at low chamber pressure during the start sequence. Data analysis suggests that the two-phase density during engine start results in a high injection velocity, possibly triggering the instabilities predicted by the Hewitt stability curves. Engine ignition instability was successfully mitigated via a higher-chamber pressure start sequence (e.g., 50% power level vs 30%) and operational propellant start temperature limits that maintained \\cold LOX" and \\warm methane" at the engine inlet. The main engine successfully demonstrated 4:1 throttling without chugging during mainstage, but chug instabilities were observed during some engine shutdown sequences at low injector pressure drop, especially during vehicle landing.

  14. CECE: Expanding the Envelope of Deep Throttling in Liquid Oxygen/Liquid Hydrogen Rocket Engines For NASA Exploration Missions

    NASA Technical Reports Server (NTRS)

    Giuliano, Victor J.; Leonard, Timothy G.; Lyda, Randy T.; Kim, Tony S.

    2010-01-01

    As one of the first technology development programs awarded by NASA under the Vision for Space Exploration, the Pratt & Whitney Rocketdyne (PWR) Deep Throttling, Common Extensible Cryogenic Engine (CECE) program was selected by NASA in November 2004 to begin technology development and demonstration toward a deep throttling, cryogenic engine supporting ongoing trade studies for NASA s Lunar Lander descent stage. The CECE program leverages the maturity and previous investment of a flight-proven hydrogen/oxygen expander cycle engine, the PWR RL10, to develop technology and demonstrate an unprecedented combination of reliability, safety, durability, throttlability, and restart capabilities in a high-energy cryogenic engine. The testbed selected for the deep throttling demonstration phases of this program was a minimally modified RL10 engine, allowing for maximum current production engine commonality and extensibility with minimum program cost. Three series of demonstrator engine tests, the first in April-May 2006, the second in March-April 2007 and the third in November-December 2008, have demonstrated up to 13:1 throttling (104% to 8% thrust range) of the hydrogen/oxygen expander cycle engine. The first two test series explored a propellant feed system instability ("chug") environment at low throttled power levels. Lessons learned from these two tests were successfully applied to the third test series, resulting in stable operation throughout the 13:1 throttling range. The first three tests have provided an early demonstration of an enabling cryogenic propulsion concept, accumulating over 5,000 seconds of hot fire time over 27 hot fire tests, and have provided invaluable system-level technology data toward design and development risk mitigation for the NASA Altair and future lander propulsion system applications. This paper describes the results obtained from the highly successful third test series as well as the test objectives and early results obtained from a fourth test series conducted over March-May 2010

  15. Bodybuilding-induced Mondor's disease of the chest wall.

    PubMed

    Tröbinger, Christian; Wiedermann, Christian J

    2017-01-01

    To describe the association of bodybuilding abdominal exercise with the development of superficial sclerosing thrombophlebitis of the anterolateral thoracoabdominal wall. A single case study. University-affiliated regional community hospital. A 54-year-old man presented with an otherwise unremarkable past medical history 4 weeks after the start of left-sided chest discomfort. He had undergone orthopedic surgery of the right shoulder three months earlier. Two months after surgery, he had re-started bodybuilding with thoracoabdominal training. Soon thereafter, he noted a painful induration at the left side of his trunk. Doppler and duplex sonography revealed complete venous occlusion compatible with sclerosing thrombophlebitis leading to a palpable, subcutaneous, cord-like lesion on the left side of his trunk. Physical examination and routine laboratory findings were normal. The lesion spontaneously resolved over a course of 3 months. Mondor's disease of the subcutaneous veins of the chest wall which has been associated with breast or axillary surgery, malignant and systemic diseases can also appear in subjects performing intense thoracoabdominal exercise training. Although it requires only symptomatic therapy, physicians and therapists must be aware of the existence of this disease because, although benign and self-limiting, malignant and systemic diseases need to be ruled out. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. DOE Office of Scientific and Technical Information (OSTI.GOV)

    NONE

    During this time period, at WVU, the authors have obtained models for the kinetics of the HAS (higher alcohol synthesis) reaction over the Co-K-MoS{sub 2}/C catalyst. The Rotoberty reactor was then replaced in the reactor system by a plug-flow tubular reactor. Accordingly, the authors re-started the investigations on sulfide catalysts. The authors encountered and solved the leak problem from the sampling valve for the non-sulfided reactor system. They also modified the system to eliminate the condensation problem. Accordingly, they are continuing their kinetic studies on the reduced Mo-Ni-K/C catalysts. They have set up an apparatus for temperature-programmed reduction (TPR) studies,more » and have obtained some interesting results on TPR characterizations. At UCC, the complete characterization of selected catalysts has been started. The authors sent nine selected types of ZnO, Zn/CrO and Zn/Cr/MnO catalysts and supports for BET surface area, SEM, XRD and ICP. They also sent fresh and spent samples of the Engelhard Zn/CrO catalyst impregnated with 3 wt% potassium for ISS and XPS testing. In Task 2, work on the design and optimization portion of this task, as well as on the fuel testing, is completed. All funds have been expended and there are no personnel working on this project.« less

  17. ART EXPERIENCED PATIENTS FOR TACKLING ATTRITION FROM HIV CARE: A MULTI-SITE COHORT STUDY.

    PubMed

    Teklu, Alula Meressa; Yirdaw, Kesetebirhan Delele

    2016-10-01

    Retention of patients on anti-retroviral treatment in Ethiopia is a challenge. Use of anti-retroviral treatment experienced patients to prepare and re-engage them when they miss follow-ups is recommended, but evidence on its effectiveness is limited. This study evaluated its effectiveness. : A retrospective cohort study in 10 randomly selected health facilities was conducted to compare outcomes before and after initiation of the adherence supporters program in HIV care and treatment from September 2001 to August 2013. Data analysis involved Kaplan-Meier survival and Log-rank test analysis on STATA statistical software Version 12 to compare survival experiences. Of 18,835 records that were available, 938 (4.36%) records with missing values were excluded and data from the remaining 17,897 was analyzed. The incidence of first instance lost to follow-up was 22.2 per 100 person-years (95% confidence interval 21.7-22.7). The risk of missing follow-ups after initiation of the program was high (Hazard Ratio –1.22, P < 0.001). The incidence of restarting after missed follow-ups was 23 per 100 PY (95% CI 22.2-24.0). The likelihood of restarting after missed follow-ups was four times higher during the period adherence supporters were present (P<0.001). Patients who stayed longer in care before missing follow ups were more likely to restart (5.7 times the chance of restarting treatment for those whose first lost to follow-up occurred at≥12 months compared to <3 months, P< 0.001).Time to restarting treatment was shorter after the initiation of the adherence supporters program (median 37 vs. 115 days). The risk of recurrence of being lost to follow-up in the presence of adherence supporters was significantly higher than when there were no adherence supporters; 38.8 (95% CI 36.3-41.6) per 100 PY vs. 26.1 (95% CI 19.8-34.4) per 100 PY, respectively. Adherence supporters were effective in improving re-engagement of patients in treatment and care after they were lost to follow-up. Yet, prevention of lost to follow-up cases has remained a challenge to the program.

  18. A Prospective Observational Study on the Predictive Value of Serum Cystatin C for Successful Weaning from Continuous Renal Replacement Therapy.

    PubMed

    Kim, Chang Seong; Bae, Eun Hui; Ma, Seong Kwon; Kim, Soo Wan

    2018-05-30

    There is a paucity of literature that investigates a biomarker associated with successful renal recovery following continuous renal replacement therapy (CRRT). Our study aimed to identify potential renal biomarkers or clinical indicators that could predict the successful weaning from CRRT. We conducted a prospective, observational study of 110 patients who had received CRRT and were weaned after renal recovery. Patients were considered to have successfully weaned from CRRT once there was no need for renal replacement therapy (RRT) for at least 14 days. For patients who had to restart dialysis within 14 days were considered unsuccessful. Of the 110 patients evaluated, 89 (80.9%) were successfully weaned from CRRT. These patients had lower serum cystatin C (CysC) levels and higher urine output than the group that restarted RRT at the time of CRRT cessation. However, the levels of serum creatinine and neutrophil gelatinase-associated lipocalin were not significantly lower in the successful group compared to the restart-RRT group. A multivariable logistic regression showed that serum CysC was an independent predictor for the successful weaning from CRRT. Furthermore, in a multivariable Cox proportional hazards analysis, the group that was successfully weaned from CRRT had a lower in-hospital mortality compared to the restarted RRT group. Serum CysC, at the time of CRRT cessation, is an independent predictor of the successful weaning from CRRT in critically ill patients with acute kidney injury. © 2018 The Author(s). Published by S. Karger AG, Basel.

  19. Inter-Disciplinary Collaboration in Support of the Post-Standby TREAT Mission

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    DeHart, Mark; Baker, Benjamin; Ortensi, Javier

    Although analysis methods have advanced significantly in the last two decades, high fidelity multi- physics methods for reactors systems have been under development for only a few years and are not presently mature nor deployed. Furthermore, very few methods provide the ability to simulate rapid transients in three dimensions. Data for validation of advanced time-dependent multi- physics is sparse; at TREAT, historical data were not collected for the purpose of validating three-dimensional methods, let alone multi-physics simulations. Existing data continues to be collected to attempt to simulate the behavior of experiments and calibration transients, but it will be insufficient formore » the complete validation of analysis methods used for TREAT transient simulations. Hence, a 2018 restart will most likely occur without the direct application of advanced modeling and simulation methods. At present, the current INL modeling and simulation team plans to work with TREAT operations staff in performing reactor simulations with MAMMOTH, in parallel with the software packages currently being used in preparation for core restart (e.g., MCNP5, RELAP5, ABAQUS). The TREAT team has also requested specific measurements to be performed during startup testing, currently scheduled to run from February to August of 2018. These startup measurements will be crucial in validating the new analysis methods in preparation for ultimate application for TREAT operations and experiment design. This document describes the collaboration between modeling and simulation staff and restart, operations, instrumentation and experiment development teams to be able to effectively interact and achieve successful validation work during restart testing.« less

  20. Effect of hydraulic retention time on deterioration/restarting of sludge anaerobic digestion: Extracellular polymeric substances and microbial response.

    PubMed

    Wei, Liangliang; An, Xiaoyan; Wang, Sheng; Xue, Chonghua; Jiang, Junqiu; Zhao, Qingliang; Kabutey, Felix Tetteh; Wang, Kun

    2017-11-01

    In this study, the transformation of the sludge-related extracellular polymeric substances (EPS) during mesophilic anaerobic digestion was characterized to assess the effect of hydraulic retention time (HRT) on reactor deterioration/restarting. Experimental HRT variations from 20 to 15 and 10d was implemented for deterioration, and from 10 to 20d for restarting. Long-term digestion at the lowest HRT (10d) resulted in significant accumulation of hydrolyzed hydrophobic materials and volatile fatty acids in the supernatants. Moreover, less efficient hydrolysis of sludge EPS, especially of proteins related substances which contributed to the deterioration of digester. Aceticlastic species of Methanosaetaceae decreased from 36.3% to 27.6% with decreasing HRT (20-10d), while hydrogenotrophic methanogens (Methanomicrobiales and Methanobacteriales) increased from 30.4% to 38.3%. Proteins and soluble microbial byproducts related fluorophores in feed sludge for the anaerobic digester changed insignificantly at high HRT, whereas the fluorescent intensity of fulvic acid-like components declined sharply once the digestion deteriorated. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Investigation of Loop Heat Pipe Survival and Restart After Extreme Cold Environment Exposure

    NASA Technical Reports Server (NTRS)

    Golliher, Eric; Ku, Jentung; Licari, Anthony; Sanzi, James

    2010-01-01

    NASA plans human exploration near the South Pole of the Moon, and other locations where the environment is extremely cold. This paper reports on the heat transfer performance of a loop heat pipe (LHP) exposed to extreme cold under the simulated reduced gravitational environment of the Moon. A common method of spacecraft thermal control is to use a LHP with ammonia working fluid. Typically, a small amount of heat is provided either by electrical heaters or by environmental design, such that the LHP condenser temperature never drops below the freezing point of ammonia. The concern is that a liquid-filled, frozen condenser would not restart, or that a thawing condenser would damage the tubing due to the expansion of ammonia upon thawing. This paper reports the results of an experimental investigation of a novel approach to avoid these problems. The LHP compensation chamber (CC) is conditioned such that all the ammonia liquid is removed from the condenser and the LHP is nonoperating. The condenser temperature is then reduced to below that of the ammonia freezing point. The LHP is then successfully restarted.

  2. Berkeley lab checkpoint/restart (BLCR) for Linux clusters

    DOE PAGES

    Hargrove, Paul H.; Duell, Jason C.

    2006-09-01

    This article describes the motivation, design and implementation of Berkeley Lab Checkpoint/Restart (BLCR), a system-level checkpoint/restart implementation for Linux clusters that targets the space of typical High Performance Computing applications, including MPI. Application-level solutions, including both checkpointing and fault-tolerant algorithms, are recognized as more time and space efficient than system-level checkpoints, which cannot make use of any application-specific knowledge. However, system-level checkpointing allows for preemption, making it suitable for responding to fault precursors (for instance, elevated error rates from ECC memory or network CRCs, or elevated temperature from sensors). Preemption can also increase the efficiency of batch scheduling; for instancemore » reducing idle cycles (by allowing for shutdown without any queue draining period or reallocation of resources to eliminate idle nodes when better fitting jobs are queued), and reducing the average queued time (by limiting large jobs to running during off-peak hours, without the need to limit the length of such jobs). Each of these potential uses makes BLCR a valuable tool for efficient resource management in Linux clusters. © 2006 IOP Publishing Ltd.« less

  3. The performance of biological anaerobic filters packed with sludge-fly ash ceramic particles (SFCP) and commercial ceramic particles (CCP) during the restart period: effect of the C/N ratios and filter media.

    PubMed

    Yue, Qinyan; Han, Shuxin; Yue, Min; Gao, Baoyu; Li, Qian; Yu, Hui; Zhao, Yaqin; Qi, Yuanfeng

    2009-11-01

    Two lab-scale upflow biological anaerobic filters (BAF) packed with sludge-fly ash ceramic particles (SFCP) and commercial ceramic particles (CCP) were employed to investigate effects of the C/N ratios and filter media on the BAF performance during the restart period. The results indicated that BAF could be restarted normally after one-month cease. The C/N ratio of 4.0 was the thresholds of nitrate removal and nitrite accumulation. TN removal and phosphate uptake reached the maximum value at the same C/N ratio of 5.5. Ammonia formation was also found and excreted a negative influence on TN removal, especially when higher C/N ratios were applied. Nutrients were mainly degraded within the height of 25 cm from the bottom. In addition, SFCP, as novel filter media manufactured by wastes-dewatered sludge and fly ash, represented a better potential in inhibiting nitrite accumulation, TN removal and phosphate uptake due to their special characteristics in comparison with CCP.

  4. Turbojet-engine Starting and Acceleration

    NASA Technical Reports Server (NTRS)

    Mc Cafferty, R. J.; Straight, D. M.

    1956-01-01

    From considerations of safety and reliability in performance of gas-turbine aircraft, it is clear that engine starting and acceleration are of utmost importance. For this reason extensive efforts have been devoted to the investigation of the factors involved in the starting and acceleration of engines. In chapter III it is shown that certain basic combustion requirements must be met before ignition can occur; consequently, the design and operation of an engine must be tailored to provide these basic requirements in the combustion zone of the engine, particularly in the vicinity of the ignition source. It is pointed out in chapter III that ignition by electrical discharges is aided by high pressure, high temperature, low gas velocity and turbulence, gaseous fuel-air mixture, proper mixture strength, and-an optimum spark. duration. The simultaneous achievement of all these requirements in an actual turbojet-engine combustor is obviously impossible, yet any attempt to satisfy as many requirements as possible will result in lower ignition energies, lower-weight ignition systems, and greater reliability. These factors together with size and cost considerations determine the acceptability of the final ignition system. It is further shown in chapter III that the problem of wall quenching affects engine starting. For example, the dimensions of the volume to be burned must be larger than the quenching distance at the lowest pressure and the most adverse fuel-air ratio encountered. This fact affects the design of cross-fire tubes between adjacent combustion chambers in a tubular-combustor turbojet engine. Only two chambers in these engines contain spark plugs; therefore, the flame must propagate through small connecting tubes between the chambers. The quenching studies indicate that if the cross-fire tubes are too narrow the flame will not propagate from one chamber to another. In order to better understand the role of the basic factors in actual engine operation, many investigations have been conducted in single combustors from gas-turbine engines and in full-scale engines in altitude tanks and in flight. The purpose of the present chapter is to discuss the results of such studies and, where possible, to interpret these results qualitatively in terms of the basic requirements reported in chapter III. The discussion parallels the three phases of turbojet engine starting: (1) Ignition of the fuel-air mixture (2) Propagation of flame throughout the combustion zone (3) Acceleration of the engine to operating speed.

  5. The hard start phenomena in hypergolic engines. Volume 1: Bibliography

    NASA Technical Reports Server (NTRS)

    Miron, Y.; Perlee, H. E.

    1974-01-01

    A bibliography of reports pertaining to the hard start phenomenon in attitude control rocket engines on Apollo spacecraft is presented. Some of the subjects discussed are; (1) combustion of hydrazine, (2) one dimensional theory of liquid fuel rocket combustion, (3) preignition phenomena in small pulsed rocket engines, (4) experimental and theoretical investigation of the fluid dynamics of rocket combustion, and (5) nonequilibrium combustion and nozzle flow in propellant performance.

  6. Starting System 2. Repair the Starter Rewind Spring. Student Manual. Small Engine Repair Series. First Edition.

    ERIC Educational Resources Information Center

    Hill, Pamela

    This student manual on repairing the starter rewind spring on a small gas engine is the third of three in an instructional package on the starting system in the Small Engine Repair Series for handicapped students. The stated purpose for the booklet is to help students learn what tools and equipment to use in repairing the starter rewind spring and…

  7. Analysis of turbojet-engine controls for afterburning starting

    NASA Technical Reports Server (NTRS)

    Phillips, W E , Jr

    1956-01-01

    A simulation procedure is developed for studying the effects of an afterburner start on a controlled turbojet engine. The afterburner start is represented by introducing a step decrease in the effective exhaust-nozzle area, after which the control returns the controlled engine variables to their initial values. The degree and speed with which the control acts are a measure of the effectiveness of the particular control system. Data are presented from five systems investigated using an electronic analog computer and the developed simulation procedure. These systems are compared with respect to steady-state errors, speed of response, and transient deviations of the system variables.

  8. ATLANTA COMMUTE VEHICLE SOAK AND START DISTRIBUTIONS AND ENGINE STARTS PER DAY: IMPACT ON MOBILE SOURCE EMISSION RATES

    EPA Science Inventory

    Georgia Institute of Technology School of Civil and Environmental Engineering researchers analyzed the 2004 vehicle activity data obtained from vehicles in the Atlanta Commuter Choice Value Pricing Initiative. The onboard monitoring equipment installed in each participating vehi...

  9. 46 CFR 112.50-3 - Hydraulic starting.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Hydraulic starting. 112.50-3 Section 112.50-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-3 Hydraulic...

  10. 46 CFR 112.50-3 - Hydraulic starting.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Hydraulic starting. 112.50-3 Section 112.50-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING EMERGENCY LIGHTING AND POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-3 Hydraulic...

  11. Restart Operator Meta-heuristics for a Problem-Oriented Evolutionary Strategies Algorithm in Inverse Mathematical MISO Modelling Problem Solving

    NASA Astrophysics Data System (ADS)

    Ryzhikov, I. S.; Semenkin, E. S.

    2017-02-01

    This study is focused on solving an inverse mathematical modelling problem for dynamical systems based on observation data and control inputs. The mathematical model is being searched in the form of a linear differential equation, which determines the system with multiple inputs and a single output, and a vector of the initial point coordinates. The described problem is complex and multimodal and for this reason the proposed evolutionary-based optimization technique, which is oriented on a dynamical system identification problem, was applied. To improve its performance an algorithm restart operator was implemented.

  12. Checkpointing for a hybrid computing node

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cher, Chen-Yong

    2016-03-08

    According to an aspect, a method for checkpointing in a hybrid computing node includes executing a task in a processing accelerator of the hybrid computing node. A checkpoint is created in a local memory of the processing accelerator. The checkpoint includes state data to restart execution of the task in the processing accelerator upon a restart operation. Execution of the task is resumed in the processing accelerator after creating the checkpoint. The state data of the checkpoint are transferred from the processing accelerator to a main processor of the hybrid computing node while the processing accelerator is executing the task.

  13. Development of Cryogenic Engine for GSLV MkIII: Technological Challenges

    NASA Astrophysics Data System (ADS)

    Praveen, RS; Jayan, N.; Bijukumar, KS; Jayaprakash, J.; Narayanan, V.; Ayyappan, G.

    2017-02-01

    Cryogenic engine capable of delivering 200 kN thrust is being developed for the first time in the country by ISRO for powering the upper stage of GSLV Mk-III, the next generation launch vehicle of ISRO capable of launching four tonne class satellites to Geo-synchronous Transfer Orbit(GTO). Development of this engine started a decade ago when various sub-systems development and testing were taken up. Starting with injector element development, the design, realization and testing of the major sub-systems viz the gas generator, turbopumps, start-up system and thrust chamber have been successfully done in a phased manner before conducting a series of developmental tests in the integrated engine mode. Apart from the major sub-systems, many critical components like the igniter, control components etc were independently developed and qualified. During the development program many challenges were faced in almost all areas of propulsion engineering. Systems engineering of the engine was another key challenge in the realization. This paper gives an outlook on various technological challenges faced in the key areas related to the engine development, insight to the solutions and measures taken to overcome the challenges.

  14. Pulsejet engine dynamics in vertical motion using momentum conservation

    NASA Astrophysics Data System (ADS)

    Cheche, Tiberius O.

    2017-03-01

    The momentum conservation law is applied to analyse the dynamics of a pulsejet engine in vertical motion in a uniform gravitational field in the absence of friction. The model predicts the existence of a terminal speed given the frequency of the short pulses. The conditions where the engine does not return to the starting position are identified. The number of short periodic pulses after which the engine returns to the starting position is found to be independent of the exhaust velocity and gravitational field intensity for a certain frequency of pulses. The pulsejet engine and turbojet engine aircraft models of dynamics are compared. Also the octopus dynamics is modelled. The paper is addressed to intermediate undergraduate students of classical mechanics and aerospace engineering.

  15. Start up system for hydrogen generator used with an internal combustion engine

    NASA Technical Reports Server (NTRS)

    Houseman, J.; Cerini, D. J. (Inventor)

    1977-01-01

    A hydrogen generator provides hydrogen rich product gases which are mixed with the fuel being supplied to an internal combustion engine for the purpose of enabling a very lean mixture of that fuel to be used, whereby nitrous oxides emitted by the engine are minimized. The hydrogen generator contains a catalyst which must be heated to a pre-determined temperature before it can react properly. To simplify the process of heating up the catalyst at start-up time, either some of the energy produced by the engine such as engine exhaust gas, or electrical energy produced by the engine, or the engine exhaust gas may be used to heat up air which is then used to heat the catalyst.

  16. X-34 40K Fastrac II Engine Test

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This is a photo of an X-34 40K Fastrac II duration test performed at the Marshall Space Flight Center test stand 116 (TS116) in June 1997. Engine ignition is started with Tea-Gas which makes the start burn green. The X-34 program was cancelled in 2001.

  17. 46 CFR 185.720 - Weekly maintenance and inspections.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... starting the engine; and (c) Each battery for rescue boat engine starting must be brought up to full charge at least once each week if: (1) The battery is of a type that requires recharging; and (2) The battery is not connected to a device that keeps it continuously charged. ...

  18. 46 CFR 185.720 - Weekly maintenance and inspections.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... starting the engine; and (c) Each battery for rescue boat engine starting must be brought up to full charge at least once each week if: (1) The battery is of a type that requires recharging; and (2) The battery is not connected to a device that keeps it continuously charged. ...

  19. 46 CFR 185.720 - Weekly maintenance and inspections.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... starting the engine; and (c) Each battery for rescue boat engine starting must be brought up to full charge at least once each week if: (1) The battery is of a type that requires recharging; and (2) The battery is not connected to a device that keeps it continuously charged. ...

  20. 46 CFR 185.720 - Weekly maintenance and inspections.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... starting the engine; and (c) Each battery for rescue boat engine starting must be brought up to full charge at least once each week if: (1) The battery is of a type that requires recharging; and (2) The battery is not connected to a device that keeps it continuously charged. ...

  1. 46 CFR 185.720 - Weekly maintenance and inspections.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... starting the engine; and (c) Each battery for rescue boat engine starting must be brought up to full charge at least once each week if: (1) The battery is of a type that requires recharging; and (2) The battery is not connected to a device that keeps it continuously charged. ...

  2. Optimizing longwall mine layouts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Minkel, M.J.

    1996-12-31

    Before spending the time to design an underground mine in detail, the mining engineer should be assured of the economic viability of the location of the layout. This has historically been a trial-and-error, iterative process. Traditional underground mine planning usually bases the layout on the geological characteristics of a deposit such as minimum seam height, quality, and the absence of faults. Whether one attempts to make a decision manually. or use traditional mine planning software, the process works something like this: First you build geological model. Then you impose a {open_quotes}best guess{close_quotes} as to which geological layers will become partmore » of the mined product, or will influence mining. Next you place your design where you believe is the best location to make a mine. Then you select equipment which you believe will cost-effectively mine the area. Finally, you schedule your equipment selection through the design over the mine life, run financial analyses and see if the rate of return is acceptable. If the NPV is acceptable, the design is accepted. If the NPV is not acceptable, the engineer has to restart the cycle of redesigning the layout, rescheduling the equipment, and restudying the economics again.« less

  3. Liquid hydrogen slosh waves excited by constant reverse gravity acceleration of geyser initiation

    NASA Technical Reports Server (NTRS)

    Hung, R. J.; Shyu, K. L.; Lee, C. C.

    1992-01-01

    The requirement to settle or to position liquid fuel over the outlet end of the spacecraft propellant tank before main engine restart poses a microgravity fluid behavior problem. Resettlement or reorientation of liquid propellant can be accomplished by providing the optimal acceleration to the spacecraft such that the propellant is reoriented over the tank outlet. In this study slosh wave excitation induced by the resettling flowfield during the course of liquid reorientation with the initiation of geyser for liquid-filled levels of 30, 50, 65, 70, and 80 percent have been studied. Characteristics of slosh waves with various frequencies excited are discussed. Slosh wave excitations will affect the fluid stress distribution exerted on the container wall and shift the fluid mass distribution inside the container, which imposes the time-dependent variations in the moment of inertia of the container. This information is important for the spacecraft control during the course of liquid reorientation.

  4. Initiation of geyser during the resettlement of cryogenic liquid under impulsive reverse gravity acceleration in microgravity environment

    NASA Technical Reports Server (NTRS)

    Hung, R. J.; Shyu, K. L.

    1991-01-01

    The requirement to settle or to position liquid fluid over the outlet end of spacecraft propellant tank prior to main engine restart poses a microgravity fluid behavior problem. Resettlement or reorientation of liquid propellant can be accomplished by providing optimal acceleration to the spacecraft such that the propellant is reoriented over the tank outlet without any vapor entrainment, any excessive geysering, or any other undesirable fluid motion for the space fluid management under microgravity environment. The purpose of present study is to investigate most efficient technique for propellant resettling through the minimization of propellant usage and weight penalties. Comparison between the constant reverse gravity acceleration and impulsive reverse gravity acceleration to be used for the activation of propellant resettlement, it shows that impulsive reverse gravity thrust is superior to constant reverse gravity thrust for liquid reorientation in a reduced gravity environment.

  5. Design and development of Shuttle Get-Away-Special experiment G-0074. [off-load capability for a full-tank propellant acquisition system

    NASA Technical Reports Server (NTRS)

    Orton, G. F.

    1984-01-01

    An experiment to investigate more versatile, lower cost surface tension propellant acquisition approaches for future satellite and spacecraft propellant tanks is designed to demonstrate a propellant off-load capability for a full-tank gallery surface tension device, such as that employed in the shuttle reaction control subsystem, and demonstrate a low-cost refillable trap concept that could be used in future orbit maneuver propulsion systems for multiple engine restarts. A Plexiglas test tank, movie camera and lights, auxiliary liquid accumulator, control electronics, battery pack, and associated valving and plumbing are used. The test liquid is Freon 113, dyed blue for color movie coverage. The fully loaded experiments weighs 106 pounds and is to be installed in a NASA five-cubic-foot flight canister. Vibration tests, acoustic tests, and high and low temperature tests were performed to quality the experiment for flight.

  6. Optimized Heat Pipe Backup Cooling System Tested with a Stirling Convertor

    NASA Technical Reports Server (NTRS)

    Tarau, Calin; Schwendeman, Carl L.; Schifer, Nicholas A.; Anderson, William G.

    2016-01-01

    Advanced Stirling Radioisotope Generator (ASRG) is an attractive energy system for select space missions, and with the addition of a VCHP, it becomes even more versatile. The ASRG is powered through thermal energy from decaying radioisotopes acting as General Purpose Heat Sources (GPHS). A Stirling engine converts the thermal energy to electrical energy and cools the GPHS [2]. The Stirling convertor must operate continuously to maintain acceptable temperatures of the GPHS and protect their cladding. The addition of alkali metal VCHP allows the Stirling to cycle on and off during a mission and can be used as a backup cooling system. The benefits of being able to turn the Stirling off are: allowing for a restart of the Stirling and reducing vibrations for sensitive measurements. The VCHP addition should also increase the efficiency of the Stirling by providing a uniform temperature distribution at the heat transfer interface into the heater head.

  7. [Durable remission attained with plasmapheresis and intravenous immunoglobulin therapy in a patient with acute exacerbation of GVHD-related myasthenia gravis].

    PubMed

    Nakashima, Jun; Itonaga, Hidehiro; Fujioka, Machiko; Chiwata, Masahiko; Sawayama, Yasushi; Yoshimura, Shunsuke; Iwanaga, Hiroshi; Taguchi, Jun; Yoshida, Shinichiro; Miyazaki, Yasushi

    2018-01-01

    A 17-year-old male underwent a second bone marrow transplantation using a 6/8 allele HLA-matched unrelated donor. On day 100 after transplantation, steroid treatment for chronic graft-versus-host disease (GVHD) was started. On day 766, the patient experienced general fatigue, followed by double vision, ptosis, and dysphagia on day 810. Based on the positivity of the acetylcholine receptor antibody and a waning electromyography pattern, he was diagnosed with GVHD-related myasthenia gravis (MG). On day 861, we initiated plasmapheresis (PE), followed by the administration of intravenous immunoglobulin (IVIg) ; this treatment attenuated the bulbar symptoms of MG. Although the steroid treatment was continued, we restarted the administration of tacrolimus. On day 2,739 after transplantation, we stopped the steroid treatment, and the patient remained in remission for MG following the cessation of the steroid treatment on day 2,897. This case suggests that PE followed by IVIg could be an effective therapeutic alternative for MG associated with GVHD.

  8. Predicting Pharmacodynamic Drug-Drug Interactions through Signaling Propagation Interference on Protein-Protein Interaction Networks.

    PubMed

    Park, Kyunghyun; Kim, Docyong; Ha, Suhyun; Lee, Doheon

    2015-01-01

    As pharmacodynamic drug-drug interactions (PD DDIs) could lead to severe adverse effects in patients, it is important to identify potential PD DDIs in drug development. The signaling starting from drug targets is propagated through protein-protein interaction (PPI) networks. PD DDIs could occur by close interference on the same targets or within the same pathways as well as distant interference through cross-talking pathways. However, most of the previous approaches have considered only close interference by measuring distances between drug targets or comparing target neighbors. We have applied a random walk with restart algorithm to simulate signaling propagation from drug targets in order to capture the possibility of their distant interference. Cross validation with DrugBank and Kyoto Encyclopedia of Genes and Genomes DRUG shows that the proposed method outperforms the previous methods significantly. We also provide a web service with which PD DDIs for drug pairs can be analyzed at http://biosoft.kaist.ac.kr/targetrw.

  9. Cerebral Amyloid Angiopathy: Diagnosis, Clinical Implications, and Management Strategies in Atrial Fibrillation.

    PubMed

    DeSimone, Christopher V; Graff-Radford, Jonathan; El-Harasis, Majd A; Rabinstein, Alejandro A; Asirvatham, Samuel J; Holmes, David R

    2017-08-29

    With an aging population, clinicians are more frequently encountering patients with atrial fibrillation who are also at risk of intracerebral hemorrhage due to cerebral amyloid angiopathy, the result of β-amyloid deposition in cerebral vessels. Cerebral amyloid angiopathy is common among elderly patients, and is associated with an increased risk of intracerebral bleeding, especially with the use of anticoagulation. Despite this association, this entity is absent in current risk-benefit analysis models, which may result in underestimation of the chance of bleeding in the subset of patients with this disease. Determining the presence and burden of cerebral amyloid angiopathy is particularly important when planning to start or restart anticoagulation after an intracerebral hemorrhage. Given the lack of randomized trial data to guide management strategies, we discuss a heart-brain team approach that includes clinician-patient shared decision making for the use of pharmacologic and nonpharmacologic approaches to diminish stroke risk. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  10. A cautionary tale on the use of antiplatelet treatment following TURP.

    PubMed

    Murray, Aileen Marie; Keville, Norah; Gray, Sam

    2014-04-04

    A pleasant 74-year-old man was discharged home following a complication-free transurethral resection of his prostate (TURP) and successful trial without catheter. Unfortunately, on postoperative day 6, he presented to A&E with chest pain requiring emergency intervention for a confirmed myocardial infarction. A drug-eluting stent was inserted into his right coronary artery and he was started on dual antiplatelet therapy of aspirin and clopidogrel. On day 7, the patient developed significant haematuria requiring transfusion and an obstructive uropathy, requiring an emergency laparotomy and 1 L of organised clot evacuation from his bladder. The dual antiplatelet treatment was restarted on day 4 postlaparotomy, following debate between both the cardiology and urology teams regarding its appropriate reintroduction. On day 7, he was rushed back to the theatre for a re-laparotomy after CT confirmed reaccumulation of clot following an acute deterioration at ward level. The patient made an excellent recovery and was discharged home with regular outpatient follow-up.

  11. Dcx Re-expression Reduces Subcortical Band Heterotopia and Seizure Threshold in an Animal Model of Neuronal Migration Disorder

    PubMed Central

    Manent, Jean-Bernard; Wang, Yu; Chang, YoonJeung; Paramasivam, Murugan; LoTurco, Joseph J

    2009-01-01

    Disorders of neuronal migration can lead to malformations of the cerebral neocortex that greatly increase the risk of seizures. It remains untested whether malformations caused by disorders in neuronal migration can be reduced by reactivating cellular migration, and whether such repair can decrease seizure risk. Here we show, in a rat model of subcortical band heterotopia (SBH) generated by in utero RNAi of Dcx, that aberrantly positioned neurons can be stimulated to migrate by re-expressing Dcx after birth. Re-starting migration in this way both reduces neocortical malformations and restores neuronal patterning. We find further that the capacity to reduce SBH has a critical period in early postnatal development. Moreover, intervention after birth reduces convulsant-induced seizure threshold to levels similar to that of malformation-free controls. These results suggest that disorders of neuronal migration may be eventually treatable by re-engaging developmental programs both to reduce the size of cortical malformations and to reduce seizure risk. PMID:19098909

  12. 46 CFR 160.135-7 - Design, construction, and performance of lifeboats.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... materials equivalent or superior in strength, design, wet out, and efficiency will be given consideration on.... (8) Starting system batteries. Any battery fitted in a totally enclosed lifeboat must be stored in a... starting battery is required per engine. (9) Exhaust. Engine exhaust must be routed away from bilge and...

  13. 46 CFR 160.135-7 - Design, construction, and performance of lifeboats.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... materials equivalent or superior in strength, design, wet out, and efficiency will be given consideration on.... (8) Starting system batteries. Any battery fitted in a totally enclosed lifeboat must be stored in a... starting battery is required per engine. (9) Exhaust. Engine exhaust must be routed away from bilge and...

  14. 46 CFR 160.135-7 - Design, construction, and performance of lifeboats.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... materials equivalent or superior in strength, design, wet out, and efficiency will be given consideration on.... (8) Starting system batteries. Any battery fitted in a totally enclosed lifeboat must be stored in a... starting battery is required per engine. (9) Exhaust. Engine exhaust must be routed away from bilge and...

  15. Dna Sequencing

    DOEpatents

    Hetrick, Robert Eugene; Hilbert, Harold Sean; Parsons, Michael Howard; Stockhausen, William Francis

    1997-10-07

    A fuel injection system used in the intake air passageway of an internal combustion engine has a strategy for reducing cold start hydrocarbon emissions. The fuel injector has an actuator which allows the fuel spray pattern to be varied from one which is widely dispersed and atomized to one which is only weakly dispersed. A strategy for varying the spray pattern during the engine warm-up period after cold start is disclosed. The strategy increases evaporation within the passageway so that cold start overfuelling and attendant hydrocarbon emissions are reduced.

  16. Method and apparatus for rapid stopping and starting of a thermoacoustic engine

    DOEpatents

    Swift, Gregory W.; Backhaus, Scott N.; Gardner, David L.

    2003-11-11

    A thermoacoustic engine-driven system with a hot heat exchanger, a regenerator or stack, and an ambient heat exchanger includes a side branch load for rapid stopping and starting, the side branch load being attached to a location in the thermoacoustic system having a nonzero oscillating pressure and comprising a valve, a flow resistor, and a tank connected in series. The system is rapidly stopped simply by opening the valve and rapidly started by closing the valve.

  17. Flight evaluation of the DEEC secondary control air-start capability

    NASA Technical Reports Server (NTRS)

    Johnson, J. B.; Nelson, J.

    1983-01-01

    The air-start capability of a secondary engine control (SEC) was tested for a DEEC-equipped F100 engine and installed in an F-15 airplane. Two air-start schedules were tested. The first was referred to as the group I schedule; the second or revised schedule was the group II start schedule. Using the group I start schedule, an airspeed of 300 knots was required to ensure successful 40- and 25-percent SEC-mode air starts. If N2 were less than 40 percent, a stall would occur when the start bleeds closed 40 sec after initiation of the air start. All JFS-assisted air starts were successful with the group start schedule. For the group II schedule, the time between pressurization and start-bleed closure ranged between 50 and 72 sec depending on altitude. All air starts were successful above 225 knots givin a 75-knot reduction in required airspeed for a successful air start. Spooldown air starts of 40 percent were successful at 200 knots at altitudes up to 10,650 m and at 175 knots at altitudes up to 6100 m. Idle rpm was lower than the desired 65 percent for air starts at higher altitudes and lower airspeeds. All JSF-assisted air starts were successful.

  18. Introduction of Virtualization Technology to Multi-Process Model Checking

    NASA Technical Reports Server (NTRS)

    Leungwattanakit, Watcharin; Artho, Cyrille; Hagiya, Masami; Tanabe, Yoshinori; Yamamoto, Mitsuharu

    2009-01-01

    Model checkers find failures in software by exploring every possible execution schedule. Java PathFinder (JPF), a Java model checker, has been extended recently to cover networked applications by caching data transferred in a communication channel. A target process is executed by JPF, whereas its peer process runs on a regular virtual machine outside. However, non-deterministic target programs may produce different output data in each schedule, causing the cache to restart the peer process to handle the different set of data. Virtualization tools could help us restore previous states of peers, eliminating peer restart. This paper proposes the application of virtualization technology to networked model checking, concentrating on JPF.

  19. Successful Retreatment of a Child with a Refractory Brainstem Ganglioglioma with Vemurafenib.

    PubMed

    Aguilera, Dolly; Janss, Anna; Mazewski, Claire; Castellino, Robert Craig; Schniederjan, Matthew; Hayes, Laura; Brahma, Barunashish; Fogelgren, Lauren; MacDonald, Tobey J

    2016-03-01

    A child with brainstem ganglioglioma underwent subtotal resection and focal radiation. Magnetic resonance imaging confirmed tumor progression 6 months later. Another partial resection revealed viable BRAF V600E-positive residual tumor. Vemurafenib (660 mg/m(2) /dose) was administered twice daily, resulting in >70% tumor reduction with sustained clinical improvement for 1 year. Vemurafenib was then terminated, but significant tumor progression occurred 3 months later. Vemurafenib was restarted, resulting in partial response. Toxicities included Grade I pruritus and Grade II rash. Vemurafenib was effectively crushed and administered in solution via nasogastric tube. We demonstrate benefit from restarting vemurafenib therapy. © 2015 Wiley Periodicals, Inc.

  20. Enhanced spatial resolution in fluorescence molecular tomography using restarted L1-regularized nonlinear conjugate gradient algorithm.

    PubMed

    Shi, Junwei; Liu, Fei; Zhang, Guanglei; Luo, Jianwen; Bai, Jing

    2014-04-01

    Owing to the high degree of scattering of light through tissues, the ill-posedness of fluorescence molecular tomography (FMT) inverse problem causes relatively low spatial resolution in the reconstruction results. Unlike L2 regularization, L1 regularization can preserve the details and reduce the noise effectively. Reconstruction is obtained through a restarted L1 regularization-based nonlinear conjugate gradient (re-L1-NCG) algorithm, which has been proven to be able to increase the computational speed with low memory consumption. The algorithm consists of inner and outer iterations. In the inner iteration, L1-NCG is used to obtain the L1-regularized results. In the outer iteration, the restarted strategy is used to increase the convergence speed of L1-NCG. To demonstrate the performance of re-L1-NCG in terms of spatial resolution, simulation and physical phantom studies with fluorescent targets located with different edge-to-edge distances were carried out. The reconstruction results show that the re-L1-NCG algorithm has the ability to resolve targets with an edge-to-edge distance of 0.1 cm at a depth of 1.5 cm, which is a significant improvement for FMT.

  1. IRWRLDA: improved random walk with restart for lncRNA-disease association prediction.

    PubMed

    Chen, Xing; You, Zhu-Hong; Yan, Gui-Ying; Gong, Dun-Wei

    2016-09-06

    In recent years, accumulating evidences have shown that the dysregulations of lncRNAs are associated with a wide range of human diseases. It is necessary and feasible to analyze known lncRNA-disease associations, predict potential lncRNA-disease associations, and provide the most possible lncRNA-disease pairs for experimental validation. Considering the limitations of traditional Random Walk with Restart (RWR), the model of Improved Random Walk with Restart for LncRNA-Disease Association prediction (IRWRLDA) was developed to predict novel lncRNA-disease associations by integrating known lncRNA-disease associations, disease semantic similarity, and various lncRNA similarity measures. The novelty of IRWRLDA lies in the incorporation of lncRNA expression similarity and disease semantic similarity to set the initial probability vector of the RWR. Therefore, IRWRLDA could be applied to diseases without any known related lncRNAs. IRWRLDA significantly improved previous classical models with reliable AUCs of 0.7242 and 0.7872 in two known lncRNA-disease association datasets downloaded from the lncRNADisease database, respectively. Further case studies of colon cancer and leukemia were implemented for IRWRLDA and 60% of lncRNAs in the top 10 prediction lists have been confirmed by recent experimental reports.

  2. 46 CFR 112.50-3 - Hydraulic starting.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Hydraulic starting. 112.50-3 Section 112.50-3 Shipping... POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-3 Hydraulic starting. A hydraulic starting system must meet the following: (a) The hydraulic starting system must be a...

  3. 46 CFR 112.50-3 - Hydraulic starting.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Hydraulic starting. 112.50-3 Section 112.50-3 Shipping... POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-3 Hydraulic starting. A hydraulic starting system must meet the following: (a) The hydraulic starting system must be a...

  4. 46 CFR 112.50-3 - Hydraulic starting.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Hydraulic starting. 112.50-3 Section 112.50-3 Shipping... POWER SYSTEMS Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-3 Hydraulic starting. A hydraulic starting system must meet the following: (a) The hydraulic starting system must be a...

  5. The hard start phenomena in hypergolic engines. Volume 2: Combustion characteristics of propellants and propellant combinations

    NASA Technical Reports Server (NTRS)

    Miron, Y.; Perlee, H. E.

    1974-01-01

    The combustion characteristics of hypergolic propellants are described. A research project was conducted to determine if the reaction control system engine propellants on Apollo spacecraft undergo explosive reaction when subjected to conditions present in the engine at the time of ignition. Combustion characteristics pertinent to the hard-start phenomenon are considered. The thermal stability of frozen mixtures of hydrazine-based fuels with nitrogen tetroxide was analyzed. Results of the tests are presented in the form of tables and graphs.

  6. Start time variability and predictability in railroad train and engine freight and passenger service employees.

    DOT National Transportation Integrated Search

    2014-04-01

    Start time variability in work schedules is often hypothesized to be a cause of railroad employee fatigue because unpredictable work start times prevent employees from planning sleep and personal activities. This report examines work start time diffe...

  7. Functional analysis of a frame-shift mutant of the dihydropyridine receptor pore subunit (α1S) expressing two complementary protein fragments

    PubMed Central

    Ahern, Chris A; Vallejo, Paola; Mortenson, Lindsay; Coronado, Roberto

    2001-01-01

    Background The L-type Ca2+ channel formed by the dihydropyridine receptor (DHPR) of skeletal muscle senses the membrane voltage and opens the ryanodine receptor (RyR1). This channel-to-channel coupling is essential for Ca2+ signaling but poorly understood. We characterized a single-base frame-shift mutant of α1S, the pore subunit of the DHPR, that has the unusual ability to function voltage sensor for excitation-contraction (EC) coupling by virtue of expressing two complementary hemi-Ca2+ channel fragments. Results Functional analysis of cDNA transfected dysgenic myotubes lacking α1S were carried out using voltage-clamp, confocal Ca2+ indicator fluoresence, epitope immunofluorescence and immunoblots of expressed proteins. The frame-shift mutant (fs-α1S) expressed the N-terminal half of α1S (M1 to L670) and the C-terminal half starting at M701 separately. The C-terminal fragment was generated by an unexpected restart of translation of the fs-α1S message at M701 and was eliminated by a M701I mutation. Protein-protein complementation between the two fragments produced recovery of skeletal-type EC coupling but not L-type Ca2+ current. Discussion A premature stop codon in the II-III loop may not necessarily cause a loss of DHPR function due to a restart of translation within the II-III loop, presumably by a mechanism involving leaky ribosomal scanning. In these cases, function is recovered by expression of complementary protein fragments from the same cDNA. DHPR-RyR1 interactions can be achieved via protein-protein complementation between hemi-Ca2+ channel proteins, hence an intact II-III loop is not essential for coupling the DHPR voltage sensor to the opening of RyR1 channel. PMID:11806762

  8. 14 CFR 23.903 - Engines.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... engine compartment) of any system that can affect an engine (other than a fuel tank if only one fuel tank...) Starting and stopping (piston engine). (1) The design of the installation must be such that risk of fire or...

  9. 14 CFR 23.903 - Engines.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... engine compartment) of any system that can affect an engine (other than a fuel tank if only one fuel tank...) Starting and stopping (piston engine). (1) The design of the installation must be such that risk of fire or...

  10. 14 CFR 33.51 - Operation test.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... STANDARDS: AIRCRAFT ENGINES Block Tests; Reciprocating Aircraft Engines § 33.51 Operation test. The... characteristics, starting, idling, acceleration, overspeeding, functioning of propeller and ignition, and any other operational characteristic of the engine. If the engine incorporates a multispeed supercharger...

  11. 14 CFR 33.51 - Operation test.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... STANDARDS: AIRCRAFT ENGINES Block Tests; Reciprocating Aircraft Engines § 33.51 Operation test. The... characteristics, starting, idling, acceleration, overspeeding, functioning of propeller and ignition, and any other operational characteristic of the engine. If the engine incorporates a multispeed supercharger...

  12. Start Your Engines: Surfing with Search Engines for Kids.

    ERIC Educational Resources Information Center

    Byerly, Greg; Brodie, Carolyn S.

    1999-01-01

    Suggests that to be an effective educator and user of the Web it is essential to know the basics about search engines. Presents tips for using search engines. Describes several search engines for children and young adults, as well as some general filtered search engines for children. (AEF)

  13. 40 CFR 86.340-79 - Gasoline-fueled engine dynamometer test run.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) Observe pre-test procedures; § 86.339; (3) Start cooling system; (4) Start engine and operate in... be 5 minutes ±30 seconds. Sample flow may begin during the warm-up; (5) Read and record all pre-test... test run. 86.340-79 Section 86.340-79 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  14. 40 CFR 86.340-79 - Gasoline-fueled engine dynamometer test run.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) Observe pre-test procedures; § 86.339; (3) Start cooling system; (4) Start engine and operate in... be 5 minutes ±30 seconds. Sample flow may begin during the warm-up; (5) Read and record all pre-test... test run. 86.340-79 Section 86.340-79 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  15. 40 CFR 86.340-79 - Gasoline-fueled engine dynamometer test run.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) Observe pre-test procedures; § 86.339; (3) Start cooling system; (4) Start engine and operate in... be 5 minutes ±30 seconds. Sample flow may begin during the warm-up; (5) Read and record all pre-test... test run. 86.340-79 Section 86.340-79 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  16. 40 CFR 86.340-79 - Gasoline-fueled engine dynamometer test run.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) Observe pre-test procedures; § 86.339; (3) Start cooling system; (4) Start engine and operate in... be 5 minutes ±30 seconds. Sample flow may begin during the warm-up; (5) Read and record all pre-test... test run. 86.340-79 Section 86.340-79 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  17. 46 CFR 160.156-7 - Design, construction and performance of rescue boats and fast rescue boats.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... materials equivalent or superior in strength, design, wet out, and efficiency will be given consideration on... this subpart) meets these requirements for fuel tanks. (9) Starting system batteries. Each battery... the rescue boat has more than one engine, then only one starting battery is required per engine. (10...

  18. 46 CFR 160.156-7 - Design, construction and performance of rescue boats and fast rescue boats.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... materials equivalent or superior in strength, design, wet out, and efficiency will be given consideration on... this subpart) meets these requirements for fuel tanks. (9) Starting system batteries. Each battery... the rescue boat has more than one engine, then only one starting battery is required per engine. (10...

  19. 46 CFR 160.156-7 - Design, construction and performance of rescue boats and fast rescue boats.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... materials equivalent or superior in strength, design, wet out, and efficiency will be given consideration on... this subpart) meets these requirements for fuel tanks. (9) Starting system batteries. Each battery... the rescue boat has more than one engine, then only one starting battery is required per engine. (10...

  20. Reusable rocket engine intelligent control system framework design, phase 2

    NASA Technical Reports Server (NTRS)

    Nemeth, ED; Anderson, Ron; Ols, Joe; Olsasky, Mark

    1991-01-01

    Elements of an advanced functional framework for reusable rocket engine propulsion system control are presented for the Space Shuttle Main Engine (SSME) demonstration case. Functional elements of the baseline functional framework are defined in detail. The SSME failure modes are evaluated and specific failure modes identified for inclusion in the advanced functional framework diagnostic system. Active control of the SSME start transient is investigated, leading to the identification of a promising approach to mitigating start transient excursions. Key elements of the functional framework are simulated and demonstration cases are provided. Finally, the advanced function framework for control of reusable rocket engines is presented.

  1. Dynamic Modeling of Starting Aerodynamics and Stage Matching in an Axi-Centrifugal Compressor

    NASA Technical Reports Server (NTRS)

    Wilkes, Kevin; OBrien, Walter F.; Owen, A. Karl

    1996-01-01

    A DYNamic Turbine Engine Compressor Code (DYNTECC) has been modified to model speed transients from 0-100% of compressor design speed. The impetus for this enhancement was to investigate stage matching and stalling behavior during a start sequence as compared to rotating stall events above ground idle. The model can simulate speed and throttle excursions simultaneously as well as time varying bleed flow schedules. Results of a start simulation are presented and compared to experimental data obtained from an axi-centrifugal turboshaft engine and companion compressor rig. Stage by stage comparisons reveal the front stages to be operating in or near rotating stall through most of the start sequence. The model matches the starting operating line quite well in the forward stages with deviations appearing in the rearward stages near the start bleed. Overall, the performance of the model is very promising and adds significantly to the dynamic simulation capabilities of DYNTECC.

  2. Development and Testing of a 6-Cylinder HCCI Engine for Distributed Generation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Flowers, D L; Martinez-Frias, J; Espinosa-Loza, F

    2005-07-12

    This paper describes the technical approach for converting a Caterpillar 3406 natural gas spark ignited engine into HCCI mode. The paper describes all stages of the process, starting with a preliminary analysis that determined that the engine can be operated by preheating the intake air with a heat exchanger that recovers energy from the exhaust gases. This heat exchanger plays a dual role, since it is also used for starting the engine. For start-up, the heat exchanger is preheated with a natural gas burner. The engine is therefore started in HCCI mode, avoiding the need to handle the potentially difficultmore » transition from SI or diesel mode to HCCI. The fueling system was modified by replacing the natural gas carburetor with a liquid petroleum gas (LPG) carburetor. This modification sets an upper limit for the equivalence ratio at {phi} {approx} 0.4, which is ideal for HCCI operation and guarantees that the engine will not fail due to knock. Equivalence ratio can be reduced below 0.4 for low load operation with an electronic control valve. Intake boosting has been a challenge, as commercially available turbochargers are not a good match for the engine, due to the low HCCI exhaust temperature. Commercial introduction of HCCI engines for stationary power will therefore require the development of turbochargers designed specifically for this mode of operation. Considering that no appropriate off-the-shelf turbocharger for HCCI engines exists at this time, we are investigating mechanical supercharging options, which will deliver the required boost pressure (3 bar absolute intake) at the expense of some reduction in the output power and efficiency. An appropriate turbocharger can later be installed for improved performance when it becomes available or when a custom turbocharger is developed. The engine is now running in HCCI mode and producing power in an essentially naturally aspirated mode. Current work focuses on developing an automatic controller for obtaining consistent combustion in the 6 cylinders. The engine will then be tested for 1000 hours to demonstrate durability. This paper presents intermediate progress towards development of an HCCI engine for stationary power generation and next steps towards achieving the project goals.« less

  3. Altitude-Wind-Tunnel Investigation of a 4000-Pound-Thrust Axial-Flow Turbojet Engine. II - Operational Characteristics. II; Operational Characteristics

    NASA Technical Reports Server (NTRS)

    Fleming, William A.

    1948-01-01

    An investigation was conducted in the Cleveland altitude wind tunnel to determine the operational characteristics of an axial flow-type turbojet engine with a 4000-pound-thrust rating over a range of pressure altitudes from 5,000 to 50,OOO feet, ram pressure ratios from 1.00 to 1.86, and temperatures from 60 deg to -50 deg F. The low-flow (standard) compressor with which the engine was originally equipped was replaced by a high-flow compressor for part of the investigation. The effects of altitude and airspeed on such operating characteristics as operating range, stability of combustion, acceleration, starting, operation of fuel-control systems, and bearing cooling were investigated. With the low-flow compressor, the engine could be operated at full speed without serious burner unbalance at altitudes up to 50,000 feet. Increasing the altitude and airspeed greatly reduced the operable speed range of the engine by raising the minimum operating speed of the engine. In several runs with the high-flow compressor the maximum engine speed was limited to less than 7600 rpm by combustion blow-out, high tail-pipe temperatures, and compressor stall. Acceleration of the engine was relatively slow and the time required for acceleration increased with altitude. At maximum engine speed a sudden reduction in jet-nozzle area resulted in an immediate increase in thrust. The engine started normally and easily below 20,000 feet with each configuration. The use of a high-voltage ignition system made possible starts at a pressure altitude of 40,000 feet; but on these starts the tail-pipe temperatures were very high, a great deal of fuel burned in and behind the tail-pipe, and acceleration was very slow. Operation of the engine was similar with both fuel regulators except that the modified fuel regulator restricted the fuel flow in such a manner that the acceleration above 6000 rpm was very slow. The bearings did not cool properly at high altitudes and high engine speeds with a low-flow compressor, and bearing cooling was even poorer with a high-flow compressor.

  4. Starting of rocket engine at conditions of simulated altitude using crude monoethylaniline and other fuels with mixed acid

    NASA Technical Reports Server (NTRS)

    Ladanyi, Dezso J; Sloop, John L; Humphrey, Jack C; Morrell, Gerald

    1950-01-01

    Experiments were conducted at sea level and pressure altitude of about 55,000 feet at various temperatures to determine starting characteristics of a commercial rocket engine using crude monoethylaniline and other fuels with mixed acid. With crude monoethylaniline, ignition difficulties were encountered at temperatures below about 20 degrees F. With mixed butyl mercaptans, water-white turpentine, and x-pinene, no starting difficulties were experienced at temperatures as low as minus 74 degrees F. Turpentine and x-pinene, however, sometimes left deposits on the injector face. With blends containing furfuryl alcohol and with other blends, difficulties were experienced either from appreciable deposits or from starting.

  5. 46 CFR 190.15-5 - Vessels using fuel having a flashpoint of 110 °F. or lower.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-5 Vessels using fuel having a... are started before the engine ignition is switched on. A red warning sign at the switch shall state that the blowers shall be operated prior to starting the engines for a sufficient time to insure at...

  6. 46 CFR 190.15-5 - Vessels using fuel having a flashpoint of 110 °F. or lower.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-5 Vessels using fuel having a... are started before the engine ignition is switched on. A red warning sign at the switch shall state that the blowers shall be operated prior to starting the engines for a sufficient time to insure at...

  7. 46 CFR 190.15-5 - Vessels using fuel having a flashpoint of 110 °F. or lower.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-5 Vessels using fuel having a... are started before the engine ignition is switched on. A red warning sign at the switch shall state that the blowers shall be operated prior to starting the engines for a sufficient time to insure at...

  8. 46 CFR 190.15-5 - Vessels using fuel having a flashpoint of 110 °F. or lower.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) OCEANOGRAPHIC RESEARCH VESSELS CONSTRUCTION AND ARRANGEMENT Ventilation § 190.15-5 Vessels using fuel having a... are started before the engine ignition is switched on. A red warning sign at the switch shall state that the blowers shall be operated prior to starting the engines for a sufficient time to insure at...

  9. Start-up and control method and apparatus for resonant free piston Stirling engine

    DOEpatents

    Walsh, Michael M.

    1984-01-01

    A resonant free-piston Stirling engine having a new and improved start-up and control method and system. A displacer linear electrodynamic machine is provided having an armature secured to and movable with the displacer and having a stator supported by the Stirling engine housing in juxtaposition to the armature. A control excitation circuit is provided for electrically exciting the displacer linear electrodynamic machine with electrical excitation signals having substantially the same frequency as the desired frequency of operation of the Stirling engine. The excitation control circuit is designed so that it selectively and controllably causes the displacer electrodynamic machine to function either as a generator load to extract power from the displacer or the control circuit selectively can be operated to cause the displacer electrodynamic machine to operate as an electric drive motor to apply additional input power to the displacer in addition to the thermodynamic power feedback to the displacer whereby the displacer linear electrodynamic machine also is used in the electric drive motor mode as a means for initially starting the resonant free-piston Stirling engine.

  10. 14 CFR 23.903 - Engines.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... a fuel tank if only one fuel tank is installed), will not: (1) Prevent the continued safe operation... operation of the remaining engines. (d) Starting and stopping (piston engine). (1) The design of the...

  11. 14 CFR 23.903 - Engines.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... a fuel tank if only one fuel tank is installed), will not: (1) Prevent the continued safe operation... operation of the remaining engines. (d) Starting and stopping (piston engine). (1) The design of the...

  12. Evaluating the Impact of E15 on Snowmobile Engine Durability and Vehicle Driveability: September 22, 2010 - August 15, 2013

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Miers, Scott A.; Blough, Jason R.

    The objective of this study was to evaluate the effects of E15 on current and legacy snowmobile engines and vehicles that could occur due to misfueling by the vehicle owner. Three test scenarios were conducted to evaluate the impact of E15, including cold-start performance and emissions, on-snow vehicle driveability, and laboratory exhaust emissions over the useful life of the engine. The eightengines tested represent current and legacy product that may exhibit sensitivity to increased ethanol blended in gasoline. Because a limited number of snowmobile engines were evaluated for this test program, the results are not statistically significant. However, the broadmore » range of engine and mixture preparation technologies, combined with the various test scenarios provide preliminaryinformation to assess potential issues with E15 use in snowmobiles. Cold-start tests were performed at -6.7 degrees C (20 degrees F), -17.8 degrees C (0 degrees F), and -28.9 degrees C (-20 degrees F). The evaluation included time to start or number of pulls to start, engine speed, exhaust gas temperature, and start-up engine emissions concentrations. Statistically significant differences instarting times were not observed for most vehicles. Snowmobile driveability was analyzed using a subjective evaluation on a controlled test course. The drivers could not easily discern which fuel the snowmobiles were using during the subjective evaluation. Durability tests were conducted to measure the emissions and performance of the snowmobiles over the useful life of the vehicles (5,000miles). There were no fuel-related engine failures on E0 or E15. Carbon monoxide emissions were generally reduced by E15 relative to E0, by from 10% to 35%. Occasional misfueling of snowmobiles with E15 is not likely to cause noticeable or immediate problems for consumers. E15 is not approved for snowmobile use, and observations made during this study support the U.S. Environmental ProtectionAgency's decision to not approve E15 for snowmobiles.« less

  13. Introducing Engineering Design through an Intelligent Rube Goldberg Implementation

    ERIC Educational Resources Information Center

    Acharya, Sushil; Sirinterlikci, Arif

    2010-01-01

    Engineering students need a head start on designing a component, a process, or a system early in their educational endeavors, and engineering design topics need to be introduced appropriately without negatively affecting students' motivation for engineering. In ENGR1010 at Robert Morris University, freshmen engineering students are introduced to…

  14. 40 CFR 91.506 - Engine sample selection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine sample selection. 91.506... (CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Manufacturer Production Line Testing Program § 91.506 Engine sample selection. (a) At the start of each model year, the marine SI engine...

  15. Efficient L1 regularization-based reconstruction for fluorescent molecular tomography using restarted nonlinear conjugate gradient.

    PubMed

    Shi, Junwei; Zhang, Bin; Liu, Fei; Luo, Jianwen; Bai, Jing

    2013-09-15

    For the ill-posed fluorescent molecular tomography (FMT) inverse problem, the L1 regularization can protect the high-frequency information like edges while effectively reduce the image noise. However, the state-of-the-art L1 regularization-based algorithms for FMT reconstruction are expensive in memory, especially for large-scale problems. An efficient L1 regularization-based reconstruction algorithm based on nonlinear conjugate gradient with restarted strategy is proposed to increase the computational speed with low memory consumption. The reconstruction results from phantom experiments demonstrate that the proposed algorithm can obtain high spatial resolution and high signal-to-noise ratio, as well as high localization accuracy for fluorescence targets.

  16. Simulated annealing with restart strategy for the blood pickup routing problem

    NASA Astrophysics Data System (ADS)

    Yu, V. F.; Iswari, T.; Normasari, N. M. E.; Asih, A. M. S.; Ting, H.

    2018-04-01

    This study develops a simulated annealing heuristic with restart strategy (SA_RS) for solving the blood pickup routing problem (BPRP). BPRP minimizes the total length of the routes for blood bag collection between a blood bank and a set of donation sites, each associated with a time window constraint that must be observed. The proposed SA_RS is implemented in C++ and tested on benchmark instances of the vehicle routing problem with time windows to verify its performance. The algorithm is then tested on some newly generated BPRP instances and the results are compared with those obtained by CPLEX. Experimental results show that the proposed SA_RS heuristic effectively solves BPRP.

  17. A Thick-Restart Lanczos Algorithm with Polynomial Filtering for Hermitian Eigenvalue Problems

    DOE PAGES

    Li, Ruipeng; Xi, Yuanzhe; Vecharynski, Eugene; ...

    2016-08-16

    Polynomial filtering can provide a highly effective means of computing all eigenvalues of a real symmetric (or complex Hermitian) matrix that are located in a given interval, anywhere in the spectrum. This paper describes a technique for tackling this problem by combining a thick-restart version of the Lanczos algorithm with deflation ("locking'') and a new type of polynomial filter obtained from a least-squares technique. Furthermore, the resulting algorithm can be utilized in a “spectrum-slicing” approach whereby a very large number of eigenvalues and associated eigenvectors of the matrix are computed by extracting eigenpairs located in different subintervals independently from onemore » another.« less

  18. Checkpoint triggering in a computer system

    DOEpatents

    Cher, Chen-Yong

    2016-09-06

    According to an aspect, a method for triggering creation of a checkpoint in a computer system includes executing a task in a processing node of the computer system and determining whether it is time to read a monitor associated with a metric of the task. The monitor is read to determine a value of the metric based on determining that it is time to read the monitor. A threshold for triggering creation of the checkpoint is determined based on the value of the metric. Based on determining that the value of the metric has crossed the threshold, the checkpoint including state data of the task is created to enable restarting execution of the task upon a restart operation.

  19. Diesel engine catalytic combustor system. [aircraft engines

    NASA Technical Reports Server (NTRS)

    Ream, L. W. (Inventor)

    1984-01-01

    A low compression turbocharged diesel engine is provided in which the turbocharger can be operated independently of the engine to power auxiliary equipment. Fuel and air are burned in a catalytic combustor to drive the turbine wheel of turbine section which is initially caused to rotate by starter motor. By opening a flapper value, compressed air from the blower section is directed to catalytic combustor when it is heated and expanded, serving to drive the turbine wheel and also to heat the catalytic element. To start, engine valve is closed, combustion is terminated in catalytic combustor, and the valve is then opened to utilize air from the blower for the air driven motor. When the engine starts, the constituents in its exhaust gas react in the catalytic element and the heat generated provides additional energy for the turbine section.

  20. 14 CFR 33.69 - Ignitions system.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.69 Ignitions system. Each engine must be equipped with an ignition system for starting the engine on the ground and in flight. An...

  1. 14 CFR 33.69 - Ignitions system.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Design and Construction; Turbine Aircraft Engines § 33.69 Ignitions system. Each engine must be equipped with an ignition system for starting the engine on the ground and in flight. An...

  2. Effect of switching off unidirectional downflow systems of operating theaters during prolonged inactivity on the period before the operating theater can safely be used.

    PubMed

    Traversari, A A L; Bottenheft, C; van Heumen, S P M; Goedhart, C A; Vos, M C

    2017-02-01

    Switching off air handling systems in operating theaters during periods of prolonged inactivity (eg, nights, weekends) can produce a substantial reduction of energy expenditure. However, little evidence is available regarding the effect of switching off the air handling system during periods of prolonged inactivity on the air quality in operating theaters during operational periods. The aim of this study is to determine the amount of time needed after restarting the ventilation system to return to a stable situation, with air quality at least equal to the situation before switching off the system. Measurements were performed in 3 operating theaters, all of them equipped with a unidirectional downflow (UDF) system. Measurements (particle counts of emitted particles with a particle size ≥0.5 µm) were taken during the start-up of the ventilation system to determine when prespecified degrees of protection were achieved. Temperature readings were taken to determine when a stable temperature difference between the periphery and the protected area was reached, signifying achievement of a stable condition. After starting up the system, the protected area achieved the required degrees of protection within 20 minutes (95% upper confidence limit). A stable temperature difference was achieved within 23 minutes (95% upper confidence limit). Both findings lie well within the period of 25 minutes normally required for preparations before the start of surgical procedures. Switching off the ventilation system during prolonged inactivity (during the night and weekend) has no negative effect on the air quality in UDF operating theaters during normal operational hours. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  3. Investigation of the I-40 Jet-Propulsion Engine in the Cleveland Altitude Wind Tunnel. V - Operational Characteristics. 5; Operational Characteristics

    NASA Technical Reports Server (NTRS)

    Golladay, Richard L.; Gendler, Stanley L.

    1947-01-01

    An investigation has been conducted in the Cleveland altitude wind tunnel to determine the operational characteristics of the I-40 jet-propulsion engine over a range of pressure altitudes from 10,000 to 50,000 feet and ram-pressure ratios from 1.00 to 1.76. Engine operational data were obtained with the engine in the standard configuration and with various modifications of the fuel system, the electrical system, and the combustion chambers. The effects of altitude and airspeed on operating speed range, starting, windmilli.ng, acceleration, speed regulation, cooling, and vibration of the standard and modified engines were determined, and damage to parts was noted. Maximum engine speed was obtainable at all altitudes and airspeeds wi th each fuel-control system investigated. The minimum idling speed was raised by increases in altitude and airspeed. The lowest minimum stable speeds were obtained with the standard configuration using 40-gallon nozzles with individual metering plugs. The engine was started normally at altitudes as high as 20,000 feet with all of the fuel systems and ignition combinations except one. Ignition at 70,000 feet was difficult and, although successful ignition occurred, acceleration was slow and usually characterized by excessive tail-pipe temperature. During windmilling investigations of the engine equipped with the standard fuel system, the engine could not be started at ram-pressure ratios of 1.1 to 1.7 at altitudes of 10,000, 20,000 and 30,000 feet. When equipped with the production barometric and Monarch 40-gallon nozzles, the engine accelerated in 12 seconds from an engine speed of 6000 rpm to 11,000 rpm at 20,000 feet and an average tail-pipe temperature of 11000 F. At the same altitude and temperature, all the engine configurations had approximately the same rate of acceleration. The Woodward governor produced the safest accelerations, inasmuch as it could be adjusted to automatically prevent acceleration blow out. The engine speed was held constant by the Woodward governor and the Edwards regulator during simulated dives and climbs at constant throttle position. The bearing cooling system was satisfactory at all altitudes and airspeeds. The engines operated without serious failure, although the exhaust cone, the tail pipe, and the airplane fuselage were damaged during altitude starts.

  4. Full Hybrid: Starting

    Science.gov Websites

    powers the vehicle at low speeds, it is larger and holds much more energy than batteries used to start also used to start the gasoline engine instantly when needed. Power Split Device: The power split low speeds, it is larger and holds much more energy than batteries used to start conventional vehicles

  5. Combustion Stability Characteristics of the Project Morpheus Liquid Oxygen/Liquid Methane Main Engine

    NASA Technical Reports Server (NTRS)

    Melcher, J. C.; Morehead, Robert L.

    2014-01-01

    The Project Morpheus liquid oxygen (LOX) / liquid methane rocket engines demonstrated acousticcoupled combustion instabilities during sea-level ground-based testing at the NASA Johnson Space Center (JSC) and Stennis Space Center (SSC). High-amplitude, 1T, 1R, 1T1R (and higher order) modes appear to be triggered by injector conditions. The instability occurred during the Morpheus-specific engine ignition/start sequence, and did demonstrate the capability to propagate into mainstage. However, the instability was never observed to initiate during mainstage, even at low power levels. The Morpheus main engine is a JSC-designed 5,000 lbf-thrust, 4:1 throttling, pressure-fed cryogenic engine using an impinging element injector design. Two different engine designs, named HD4 and HD5, and two different builds of the HD4 engine all demonstrated similar instability characteristics. Through the analysis of more than 200 hot fire tests on the Morpheus vehicle and SSC test stand, a relationship between ignition stability and injector/chamber pressure was developed. The instability has the distinct characteristic of initiating at high relative injection pressure drop (dP) at low chamber pressure (Pc); i.e., instabilities initiated at high dP/Pc at low Pc during the start sequence. The high dP/Pc during start results during the injector /chamber chill-in, and is enhanced by hydraulic flip in the injector orifice elements. Because of the fixed mixture ratio of the existing engine design (the main valves share a common actuator), it is not currently possible to determine if LOX or methane injector dP/Pc were individual contributors (i.e., LOX and methane dP/Pc typically trend in the same direction within a given test). The instability demonstrated initiation characteristic of starting at or shortly after methane injector chillin. Colder methane (e.g., sub-cooled) at the injector inlet prior to engine start was much more likely to result in an instability. A secondary effect of LOX sub-cooling was also possibly observed; greater LOX sub- cooling improved stability. Some tests demonstrated a low-amplitude 1L-1T instability prior to LOX injector chill-in. The Morpheus main engine also demonstrated chug instabilities during some engine shutdown sequences on the flight vehicle and SSC test stand. The chug instability was also infrequently observed during the startup sequence. The chug instabilities predictably initiated at low dP/Pc at low Pc. The chug instabilities were always self-limiting; startup chug instabilities terminated during throttle-up and shutdown chug instabilities decayed by shutdown termination.

  6. Friction Stir Weld Restart+Reweld Repair Allowables

    NASA Technical Reports Server (NTRS)

    Clifton, Andrew

    2008-01-01

    A friction stir weld (FSW) repair method has been developed and successfully implemented on Al 2195 plate material for the Space Shuttle External Fuel Tank (ET). The method includes restarting the friction stir weld in the termination hole of the original weld followed by two reweld passes. Room temperature and cryogenic temperature mechanical properties exceeded minimum FSW design strength and compared well with the development data. Simulated service test results also compared closely to historical data for initial FSW, confirming no change to the critical flaw size or inspection requirements for the repaired weld. Testing of VPPA fusion/FSW intersection weld specimens exhibited acceptable strength and exceeded the minimum design value. Porosity, when present at the intersection was on the root side toe of the fusion weld, the "worst case" being 0.7 inch long. While such porosity may be removed by sanding, this "worst case" porosity condition was tested "as is" and demonstrated that porosity did not negatively affect the strength of the intersection weld. Large, 15-inch "wide panels" FSW repair welds were tested to demonstrate strength and evaluate residual stresses using photo stress analysis. All results exceeded design minimums, and photo stress analysis showed no significant stress gradients due to the presence of the restart and multi-pass FSW repair weld.

  7. Data assimilation for unsaturated flow models with restart adaptive probabilistic collocation based Kalman filter

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Man, Jun; Li, Weixuan; Zeng, Lingzao

    2016-06-01

    The ensemble Kalman filter (EnKF) has gained popularity in hydrological data assimilation problems. As a Monte Carlo based method, a relatively large ensemble size is usually required to guarantee the accuracy. As an alternative approach, the probabilistic collocation based Kalman filter (PCKF) employs the polynomial chaos to approximate the original system. In this way, the sampling error can be reduced. However, PCKF suffers from the so-called "curse of dimensionality". When the system nonlinearity is strong and number of parameters is large, PCKF could be even more computationally expensive than EnKF. Motivated by most recent developments in uncertainty quantification, we proposemore » a restart adaptive probabilistic collocation based Kalman filter (RAPCKF) for data assimilation in unsaturated flow problems. During the implementation of RAPCKF, the important parameters are identified and active PCE basis functions are adaptively selected. The "restart" technology is used to eliminate the inconsistency between model parameters and states. The performance of RAPCKF is tested with numerical cases of unsaturated flow models. It is shown that RAPCKF is more efficient than EnKF with the same computational cost. Compared with the traditional PCKF, the RAPCKF is more applicable in strongly nonlinear and high dimensional problems.« less

  8. Manufacturing Technology for Shipbuilding

    DTIC Science & Technology

    1983-01-01

    during which time there was an interface of Japanese and American shipbuilding concepts and methodology . Those two years of work resulted in many...lanes is of paramount importance in maintaining a smoothy orderly flow of pre-fabricated steel. Occasionally, the process lanes may fall behind schedule...design methodology . The earlier the start that Engineering has, the better the chance that all required engineering work will be completed at start of

  9. Coal-Fired Rocket Engine

    NASA Technical Reports Server (NTRS)

    Anderson, Floyd A.

    1987-01-01

    Brief report describes concept for coal-burning hybrid rocket engine. Proposed engine carries larger payload, burns more cleanly, and safer to manufacture and handle than conventional solid-propellant rockets. Thrust changeable in flight, and stops and starts on demand.

  10. The hard start phenomena in hypergolic engines. Volume 4: The chemistry of hydrazine fuels and nitrogen tetroxide propellant systems

    NASA Technical Reports Server (NTRS)

    Miron, Y.; Perlee, H. E.

    1974-01-01

    The various chemical reactions that occur and that could possibly occur in the RCS engines utilizing hydrazine-type fuel/nitrogen tetroxide propellant systems, prior to ignition (preignition), during combustion, and after combustion (postcombustion), and endeavors to relate the hard-start phenomenon to some of these reactions are discussed. The discussion is based on studies utilizing a variety of experimental techniques and apparatus as well as current theories of chemical reactions and reaction kinetics. The chemical reactions were studied in low pressure gas flow reactors, low temperature homogeneous- and heterogeneous-phase reactors, simulated two-dimensional (2-D) engines, and scaled and full size engines.

  11. The hard start phenomena in hypergolic engines. Volume 3: Physical and combustion characteristics of engine residuals

    NASA Technical Reports Server (NTRS)

    Miron, Y.; Perlee, H. E.

    1974-01-01

    An investigation was conducted to determine the cause of starting problems in the hypergolic rocket engines of the Apollo reaction control (RCS) engines. The scope of the investigation was as follows: (1) to establish that chemical reactions occurred during the preignition and post combustion periods, (2) to identify the chemical species of the products of preignition and post combustion reaction, and (3) to determine the explosive nature of the identified species. The methods used in identifying the chemical products are described species. The infrared spectra, X-ray spectra, and other signatures of the compounds are presented. The physical and explosion characteristics of various hypergolic agents are reported.

  12. The History of Chemical Engineering and Pedagogy: The Paradox of Tradition and Innovation

    ERIC Educational Resources Information Center

    Wankat, Phillip C.

    2009-01-01

    The Massachusetts Institute of Technology started the first US chemical engineering program six score years ago. Since that time, the chemical engineering curriculum has evolved. The latest versions of the curriculum are attempts to broaden chemical engineering to add product engineering, biology and nanotechnology to the traditional process…

  13. Motivation of Students Who Switch from Engineering to Engineering Technology

    ERIC Educational Resources Information Center

    Ramirez, Nichole

    2017-01-01

    A set of studies is reported describing the demographics, outcomes, and motivations of students who start in engineering and switch their major to engineering technology. There has been extensive research in engineering persistence, but little focus has been given to the "T" in STEM. Most research combines technology with other science…

  14. The Amateur Scientist.

    ERIC Educational Resources Information Center

    Walker, Jearl

    1985-01-01

    Describes experiments using fluidyne engines. These engines (which have liquid pistons), started by external heat sources, are used primarily for pumping water. Examples of various engines built from U-shaped tubes or from coiled tubes in fruit jars are provided. (DH)

  15. Economical launching and accelerating control strategy for a single-shaft parallel hybrid electric bus

    NASA Astrophysics Data System (ADS)

    Yang, Chao; Song, Jian; Li, Liang; Li, Shengbo; Cao, Dongpu

    2016-08-01

    This paper presents an economical launching and accelerating mode, including four ordered phases: pure electrical driving, clutch engagement and engine start-up, engine active charging, and engine driving, which can be fit for the alternating conditions and improve the fuel economy of hybrid electric bus (HEB) during typical city-bus driving scenarios. By utilizing the fast response feature of electric motor (EM), an adaptive controller for EM is designed to realize the power demand during the pure electrical driving mode, the engine starting mode and the engine active charging mode. Concurrently, the smoothness issue induced by the sequential mode transitions is solved with a coordinated control logic for engine, EM and clutch. Simulation and experimental results show that the proposed launching and accelerating mode and its control methods are effective in improving the fuel economy and ensure the drivability during the fast transition between the operation modes of HEB.

  16. 40 CFR 86.237-94 - Dynamometer test run, gaseous emissions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... approximately 7.5 miles (12.1 kilometers) and a hot start drive of approximately 3.6 miles (5.8 kilometers). (b... and hot start test. The cold start test is divided into two periods. The first period, representing..., consists of the remainder of the driving schedule, including engine shutdown. The hot start test is...

  17. 40 CFR 86.237-94 - Dynamometer test run, gaseous emissions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... approximately 7.5 miles (12.1 kilometers) and a hot start drive of approximately 3.6 miles (5.8 kilometers). (b... and hot start test. The cold start test is divided into two periods. The first period, representing..., consists of the remainder of the driving schedule, including engine shutdown. The hot start test is...

  18. 40 CFR 86.237-94 - Dynamometer test run, gaseous emissions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... approximately 7.5 miles (12.1 kilometers) and a hot start drive of approximately 3.6 miles (5.8 kilometers). (b... and hot start test. The cold start test is divided into two periods. The first period, representing..., consists of the remainder of the driving schedule, including engine shutdown. The hot start test is...

  19. Motor Starters

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The power factor controller (PFC) was invented by a NASA engineer. It matches voltage with a motor's actual need by sensing shifts in the relationship between voltage and current flow. With the device, power can be trimmed as much as 65%. Intellinet adopted this technology and designed "soft start" and "load-responsive" control modes to start engines gradually and recycle voltage without reducing motor speed. Other features are lower motor heat and faster fault identification.

  20. Starting System 1. Check and Replace the Starter Rewind Rope. Student Manual. Small Engine Repair Series. First Edition.

    ERIC Educational Resources Information Center

    Hill, Pamela

    This student manual on checking and replacing the starter rewind rope is the second of three in an instructional package on the starting system in the Small Engine Repair Series for handicapped students. The stated purpose for the booklet is to help students learn what tools and equipment to use in checking and replacing the starter rewind rope…

  1. A personal sampler for aircraft engine cold start particles: laboratory development and testing.

    PubMed

    Armendariz, Alfredo; Leith, David

    2003-01-01

    Industrial hygienists in the U.S. Air Force are concerned about exposure of their personnel to jet fuel. One potential source of exposure for flightline ground crews is the plume emitted during the start of aircraft engines in extremely cold weather. The purpose of this study was to investigate a personal sampler, a small tube-and-wire electrostatic precipitator (ESP), for assessing exposure to aircraft engine cold start particles. Tests were performed in the laboratory to characterize the sampler's collection efficiency and to determine the magnitude of adsorption and evaporation artifacts. A low-temperature chamber was developed for the artifact experiments so tests could be performed at temperatures similar to actual field conditions. The ESP collected particles from 0.5 to 20 micro m diameter with greater than 98% efficiency at particle concentrations up to 100 mg/m(3). Adsorption artifacts were less than 5 micro g/m(3) when sampling a high concentration vapor stream. Evaporation artifacts were significantly lower for the ESP than for PVC membrane filters across a range of sampling times and incoming vapor concentrations. These tests indicate that the ESP provides more accurate exposure assessment results than traditional filter-based particle samplers when sampling cold start particles produced by an aircraft engine.

  2. Alpha Thalassemia/Mental Retardation Syndrome X-linked Gene Product ATRX Is Required for Proper Replication Restart and Cellular Resistance to Replication Stress*

    PubMed Central

    Leung, Justin Wai-Chung; Ghosal, Gargi; Wang, Wenqi; Shen, Xi; Wang, Jiadong; Li, Lei; Chen, Junjie

    2013-01-01

    Alpha thalassemia/mental retardation syndrome X-linked (ATRX) is a member of the SWI/SNF protein family of DNA-dependent ATPases. It functions as a chromatin remodeler and is classified as an SNF2-like helicase. Here, we showed somatic knock-out of ATRX displayed perturbed S-phase progression as well as hypersensitivity to replication stress. ATRX is recruited to sites of DNA damage, required for efficient checkpoint activation and faithful replication restart. In addition, we identified ATRX as a binding partner of MRE11-RAD50-NBS1 (MRN) complex. Together, these results suggest a non-canonical function of ATRX in guarding genomic stability. PMID:23329831

  3. Psychological adaptation among residents following restart of Three Mile Island.

    PubMed

    Prince-Embury, S; Rooney, J F

    1995-01-01

    Psychological adaptation is examined in a sample of residents who remained in the vicinity of Three Mile Island following the restart of the nuclear generating facility which had been shut down since the 1979 accident. Findings indicate a lowering of psychological symptoms between 1985 and 1989 in spite of increased lack of control, less faith in experts and increased fear of developing cancer. The suggestion is made that reduced stress might have been related to a process of adaptation whereby a cognition of emergency preparedness was integrated by some of these residents as a modulating cognitive element. Findings also indicate that "loss of faith in experts" is a persistently salient cognition consistent with the "shattered assumptions" theory of victimization.

  4. Life stage differences in resident coping with restart of the Three Mile Island nuclear generating facility.

    PubMed

    Prince-Embury, S; Rooney, J F

    1990-12-01

    A study of residents who remained in the vicinity of Three Mile Island (TMI) immediately following the restart of the nuclear generating plant revealed that older residents employed a more emotion-focused coping style in the face of this event than did younger residents. Coping style was, however, unrelated to the level of psychological symptoms for these older residents, whereas demographic variables were related. Among younger residents, on the other hand, coping style was related to the level of psychological symptoms, whereas demographic variables were not. Among younger residents, emotion-focused coping was associated with more symptoms and problem-focused coping was associated with fewer symptoms, contradicting previous findings among TMI area residents.

  5. Method and apparatus for reducing cold-phase emissions by utilizing oxygen-enriched intake air

    DOEpatents

    Poola, Ramesh B.; Sekar, Ramanujam R.; Stork, Kevin C.

    1997-01-01

    An oxygen-enriched air intake control system for an internal combustion engine includes air directing apparatus to control the air flow into the intake of the engine. During normal operation of the engine, ambient air flowing from an air filter of the engine flows through the air directing apparatus into the intake of the engine. In order to decrease the amount of carbon monoxide (CO) and hydrocarbon (HC) emissions that tend to be produced by the engine during a short period of time after the engine is started, the air directing apparatus diverts for a short period of time following the start up of the engine at least a portion of the ambient air from the air filter through a secondary path. The secondary path includes a selectively permeable membrane through which the diverted portion of the ambient air flows. The selectively permeable membrane separates nitrogen and oxygen from the diverted air so that oxygen enriched air containing from about 23% to 25% oxygen by volume is supplied to the intake of the engine.

  6. J-2X engine test

    NASA Image and Video Library

    2011-07-26

    A plume of steam signals a successful engine start of the J-2X rocket engine on the A-3 Test Stand at Stennis Space Center on July 26. The 3.7-second test was the second on the next-generation engine, which is being developed for NASA by Pratt & Whitney Rocketdyne.

  7. 40 CFR 90.706 - Engine sample selection.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine sample selection. 90.706 Section...) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19 KILOWATTS Manufacturer Production Line Testing Program § 90.706 Engine sample selection. (a) At the start of each model year, the small...

  8. 40 CFR 90.706 - Engine sample selection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine sample selection. 90.706... (CONTINUED) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19 KILOWATTS Manufacturer Production Line Testing Program § 90.706 Engine sample selection. (a) At the start of each model year, the...

  9. VRLA automotive batteries for stop&go and dual battery systems

    NASA Astrophysics Data System (ADS)

    May, G. J.; Calasanzio, D.; Aliberti, R.

    The electrical power requirements for vehicles are continuing to increase and evolve. A substantial amount of effort has been directed towards the development of 36/42 V systems as a route to higher power with reduced current levels but high implementation costs have resulted in the introduction of these systems becoming deferred. In the interim, however, alternator power outputs at 14 V are being increased substantially and at the same time the requirements for batteries are becoming more intensive. In particular, stop&go systems and wire-based vehicle systems are resulting in new demands. For stop&go, the engine is stopped each time the vehicle comes to rest and is restarted when the accelerator is pressed again. This results in an onerous duty cycle with many shallow discharge cycles. Flooded lead-acid batteries cannot meet this duty cycle and valve-regulated lead-acid (VRLA) batteries are needed to meet the demands that are applied. For wire-based systems, such as brake-by-wire or steer-by-wire, electrical power has become more critical and although the alternator and battery provide double redundancy, triple redundancy with a small reserve battery is specified. In this case, a small VRLA battery can be used and is optimised for standby service rather than for repeated discharges. The background to these applications is considered and test results under simulated operating conditions are discussed. Good performance can be obtained in batteries adapted for both applications. Battery management is also critical for both applications: in stop&go service, the state-of-charge (SOC) and state-of-health (SOH) need to be monitored to ensure that the vehicle can be restarted; for reserve or back-up batteries, the SOC and SOH are monitored to verify that the battery is always capable of carrying out the duty cycle if required. Practical methods of battery condition monitoring will be described.

  10. Rocketdyne - SE-7 and SE-8 Engines. Chapter 4, Appendix F

    NASA Technical Reports Server (NTRS)

    Harmon, Tim

    2009-01-01

    The 70-pound SE-7 engine is very similar with its two valves, ablative material, a silicon carbide liner, a silicon carbide throat, and overall configuration. There were different wraps. One had a ninety-degree ablative material orientation. That is important because it caused problems with the SE-8, but not for this application. It was not overly stressed. It was a validation of the off-the-shelf application approach. There were two SE-7 engines located on the stage near the bottom. They had their own propellant tanks. That was the application. All it did was give a little bit of gravity by firing to push the propellants to the bottom of the tanks for start or restart. It was not a particularly complicated setup. (See Slides 6 and 7, Appendix F) What had we learned? This was a proven engine in a space environment. There weren't any development issues. Off-the-shelf seemed to work. There were no operational issues, which made the SE-7 very cost-effective. Besides NASA, the customer for this application was the Douglas Aircraft Company. Douglas decided the off-the-shelf idea was cost-effective. With the Gemini Program, the company was McDonnell Aircraft Corporation, which was part of the reason the off-the-shelf idea was applied to the Apollo. (See Slide 8, Appendix F) However, here are some differences between Apollo and Gemini vehicles. For one thing, the Apollo vehicle was really moving at high speed when it re-entered the atmosphere. Instead of a mere 17,000 miles per hour, it was going 24,000 miles per hour. That meant the heat load was four times as high on the Apollo vehicle as on the Gemini craft. Things were vibrating a little more. We had two redundant systems. Apollo was redundant where it could be as much as possible. That was really a keystone or maybe an anchor point for Apollo. We decided to pursue the off-the-shelf approach. However, the prime contractor was a different entity - the North American Space Division. They thought they ought to tune up this off-the-shelf setup. It was a similar off-the-shelf application, but at a higher speed. They wanted to improve it. What they wanted to improve was the material performance of silicon carbide. They were uncomfortable with the cracks they were seeing. They were uncomfortable with the cracks in the throat, and feeling that the environment was a little tougher, that maybe it was going to rattle, perhaps something would fall out, and they would have a problem. They wanted to eliminate the ceramic liner, and they wanted a different throat material. (See Slides 9 and 10, Appendix F) The Rocketdyne solutions were to replace silicon carbide material with a more forgiving ceramic material. Also, due to the multiple locations within the vehicle, the shape of the nozzles varied. Some nozzles were long, and some nozzles were short. We came up with a single engine design with variable nozzle extensions and configurations to fit particular vehicle locations. (See Slides 10 and 11, Appendix F)

  11. Evaluation of Start Transient Oscillations with the J-2X Engine Gas Generator Assembly

    NASA Technical Reports Server (NTRS)

    Hulka, J. R.; Morgan, C. J.; Casiano, M. J.

    2015-01-01

    During development of the gas generator for the liquid oxygen/liquid hydrogen propellant J-2X rocket engine, distinctive and oftentimes high-amplitude pressure oscillations and hardware vibrations occurred during the start transient of nearly every workhorse gas generator assembly test, as well as during many tests of engine system hardware. These oscillations appeared whether the steady-state conditions exhibited stable behavior or not. They occurred similarly with three different injector types, and with every combustion chamber configuration tested, including chamber lengths ranging over a 5:1 range, several different nozzle types, and with or without a side branch line simulating a turbine spin start gas supply line. Generally, two sets of oscillations occurred, one earlier in the start transient and at higher frequencies, and the other almost immediately following and at lower frequencies. Multiple dynamic pressure measurements in the workhorse combustion chambers indicated that the oscillations were associated with longitudinal acoustic modes of the combustion chambers, with the earlier and higher frequency oscillation usually related to the second longitudinal acoustic mode and the later and lower frequency oscillation usually related to the first longitudinal acoustic mode. Given that several early development gas generator assemblies exhibited unstable behavior at frequencies near the first longitudinal acoustic modes of longer combustion chambers, the start transient oscillations are presumed to provide additional insight into the nature of the combustion instability mechanisms. Aspects of the steadystate oscillations and combustion instabilities from development and engine system test programs have been reported extensively in the three previous JANNAF Liquid Propulsion Subcommittee meetings (see references below). This paper describes the hardware configurations, start transient sequence operations, and transient and dynamic test data during the start transient. The implications of these results on previous analyses and understanding of the combustion instability observed during steady-state conditions, especially the effects of injector influences, is discussed.

  12. SHINE Virtual Machine Model for In-flight Updates of Critical Mission Software

    NASA Technical Reports Server (NTRS)

    Plesea, Lucian

    2008-01-01

    This software is a new target for the Spacecraft Health Inference Engine (SHINE) knowledge base that compiles a knowledge base to a language called Tiny C - an interpreted version of C that can be embedded on flight processors. This new target allows portions of a running SHINE knowledge base to be updated on a "live" system without needing to halt and restart the containing SHINE application. This enhancement will directly provide this capability without the risk of software validation problems and can also enable complete integration of BEAM and SHINE into a single application. This innovation enables SHINE deployment in domains where autonomy is used during flight-critical applications that require updates. This capability eliminates the need for halting the application and performing potentially serious total system uploads before resuming the application with the loss of system integrity. This software enables additional applications at JPL (microsensors, embedded mission hardware) and increases the marketability of these applications outside of JPL.

  13. Assessment, development, and application of combustor aerothermal models

    NASA Technical Reports Server (NTRS)

    Holdeman, J. D.; Mongia, H. C.; Mularz, E. J.

    1989-01-01

    The gas turbine combustion system design and development effort is an engineering exercise to obtain an acceptable solution to the conflicting design trade-offs between combustion efficiency, gaseous emissions, smoke, ignition, restart, lean blowout, burner exit temperature quality, structural durability, and life cycle cost. For many years, these combustor design trade-offs have been carried out with the help of fundamental reasoning and extensive component and bench testing, backed by empirical and experience correlations. Recent advances in the capability of computational fluid dynamics codes have led to their application to complex 3-D flows such as those in the gas turbine combustor. A number of U.S. Government and industry sponsored programs have made significant contributions to the formulation, development, and verification of an analytical combustor design methodology which will better define the aerothermal loads in a combustor, and be a valuable tool for design of future combustion systems. The contributions made by NASA Hot Section Technology (HOST) sponsored Aerothermal Modeling and supporting programs are described.

  14. Coevolution in management fashion: an agent-based model of consultant-driven innovation.

    PubMed

    Strang, David; David, Robert J; Akhlaghpour, Saeed

    2014-07-01

    The rise of management consultancy has been accompanied by increasingly marked faddish cycles in management techniques, but the mechanisms that underlie this relationship are not well understood. The authors develop a simple agent-based framework that models innovation adoption and abandonment on both the supply and demand sides. In opposition to conceptions of consultants as rhetorical wizards who engineer waves of management fashion, firms and consultants are treated as boundedly rational actors who chase the secrets of success by mimicking their highest-performing peers. Computational experiments demonstrate that consultant-driven versions of this dynamic in which the outcomes of firms are strongly conditioned by their choice of consultant are robustly faddish. The invasion of boom markets by low-quality consultants undercuts popular innovations while simultaneously restarting the fashion cycle by prompting the flight of high-quality consultants into less densely occupied niches. Computational experiments also indicate conditions involving consultant mobility, aspiration levels, mimic probabilities, and client-provider matching that attenuate faddishness.

  15. Microgravity liquid propellant management

    NASA Technical Reports Server (NTRS)

    Hung, R. J.

    1990-01-01

    The requirement to settle or to position liquid fluid over the outlet end of a spacecraft propellant tank prior to main engine restart, poses a microgravity fluid behavior problem. Resettlement or reorientation of liquid propellant can be accomplished by providing optimal acceleration to the spacecraft such that the propellant is reoriented over the tank outlet without any vapor entrainment, any excessive geysering, or any other undersirable fluid motion for the space fluid management under microgravity environment. The most efficient technique is studied for propellant resettling through the minimization of propellant usage and weight penalties. Both full scale and subscale liquid propellant tank of Space Transfer Vehicle were used to simulate flow profiles for liquid hydrogen reorientation over the tank outlet. In subscale simulation, both constant and impulsive resettling acceleration were used to simulate the liquid flow reorientation. Comparisons between the constant reverse gravity acceleration and impulsive reverse gravity acceleration to be used for activation of propellant resettlement shows that impulsive reverse gravity thrust is superior to constant reverse gravity thrust.

  16. Demonstration of diesel fired coolant heaters in school bus applications : final report.

    DOT National Transportation Integrated Search

    2010-04-01

    Engine block pre-heating can reduce fuel consumption, decrease pollution, extend engine life, and it is often necessary for reliably starting diesel engines in cold climates. This report describes the application and experience of applying 36 diesel ...

  17. SAGRAD: A Program for Neural Network Training with Simulated Annealing and the Conjugate Gradient Method.

    PubMed

    Bernal, Javier; Torres-Jimenez, Jose

    2015-01-01

    SAGRAD (Simulated Annealing GRADient), a Fortran 77 program for computing neural networks for classification using batch learning, is discussed. Neural network training in SAGRAD is based on a combination of simulated annealing and Møller's scaled conjugate gradient algorithm, the latter a variation of the traditional conjugate gradient method, better suited for the nonquadratic nature of neural networks. Different aspects of the implementation of the training process in SAGRAD are discussed, such as the efficient computation of gradients and multiplication of vectors by Hessian matrices that are required by Møller's algorithm; the (re)initialization of weights with simulated annealing required to (re)start Møller's algorithm the first time and each time thereafter that it shows insufficient progress in reaching a possibly local minimum; and the use of simulated annealing when Møller's algorithm, after possibly making considerable progress, becomes stuck at a local minimum or flat area of weight space. Outlines of the scaled conjugate gradient algorithm, the simulated annealing procedure and the training process used in SAGRAD are presented together with results from running SAGRAD on two examples of training data.

  18. Unsteady state flow and stagnation in distribution systems affect the biological stability of drinking water.

    PubMed

    Manuel, C M; Nunes, O C; Melo, L F

    2010-01-01

    The effects of water stagnation and flushing on the biological stability of drinking water were studied by promoting the formation of biofilms under continuous flow (turbulent or laminar) and subsequently subjecting them to unsteady hydraulic situations. Independently of the flow regime under which the biofilm was formed, stagnation promoted bacterial accumulation, either in attached or suspended form, which were carried away in higher numbers when flow was re-started, thereby compromising its biological quality. In all cases, Betaproteobacteria was the dominant phylogenetic group, although Gamma and Alpha subclasses were also present. These results suggest that special attention should be given to the biological quality of drinking water where consumption is subjected to strongly variable demands such as in seasonal hotels, week-end houses or dental clinics after week-ends as abnormal changes may have occurred in the microbiological parameters. Moreover, this study showed that the cultivable bacterial numbers are not related to those of total bacteria and, thus, should not be the basis for the routine tests of bacteriological control in these systems.

  19. Investigation of Capillary Limit in a Loop Heat Pipe

    NASA Technical Reports Server (NTRS)

    Ku, Jentung; Ottenstein, Laura; Rogers, Paul; Cheung, Kwok; Obenschain, Arthur F. (Technical Monitor)

    2001-01-01

    This paper presets an experimental study on the capillary limit of a loop heat pipe (LHP) at low powers. The slow thermal response of the loop at low powers made it possible to observe interactions among various components after the capillary limit was exceeded. The capillary limit at low powers was achieved by imposing additional pressure drops on the vapor line through the use of a metering valve. A differential pressure transducer was also used to measure the pressure drop across the evaporator and the compensation chamber (CC). Test results show that when the capillary limit is exceeded, vapor will penetrate the primary wick, resulting in a partial dry-out of the evaporator and a rapid increase of the CC temperature. Because the evaporator can tolerate vapor bubbles, the LHP will continue to function and may reach a new steady state at the higher temperature. Thus, the LHP will exhibit a graceful degradation in performance rather than a complete failure. Moreover, the loop can recover from a partial dry-out by reducing the heat load without a re-start.

  20. Acute pancreatitis attributed to the use of interferon alfa-2b.

    PubMed

    Eland, I A; Rasch, M C; Sturkenboom, M J; Bekkering, F C; Brouwer, J T; Delwaide, J; Belaiche, J; Houbiers, G; Stricker, B H

    2000-07-01

    Two patients experienced episodes of acute pancreatitis shortly after starting treatment with interferon alfa-2b (IFN-alpha) for a chronic hepatitis C infection. The first patient was a 40-year-old man who developed acute pancreatitis after 15 weeks of treatment with 3 MU IFN-alpha subcutaneously (SC) 3 times weekly and 1200 mg ribavirin. After disappearance of symptoms and normalization of laboratory values, oral intake of solid foods and IFN-alpha therapy were restarted. Within hours, a relapse of acute pancreatitis occurred. A rechallenge with IFN-alpha 4 days later was followed by a prompt increase in serum lipase level, and IFN-alpha therapy was discontinued. The second patient was a 38-year-old man who developed acute pancreatitis 2 hours after SC administration of 5 MU IFN-alpha. Ultrasound endoscopy showed sludge in the gallbladder. The patient was rechallenged 5 weeks later with 3 MU IFN-alpha SC. Although serum amylase and lipase levels increased after readministration of IFN-alpha, treatment was continued. The patient was readmitted 2 weeks later with severe abdominal pain, and IFN-alpha administration was discontinued. Considering the temporal relationship between the start of IFN-alpha treatment and development of acute pancreatitis, the absence of other clear etiologic factors for acute pancreatitis, disappearance of symptoms after discontinuation of IFN-alpha, and positive reactions to rechallenge, IFN-alpha is the most probable cause for development of acute pancreatitis in these patients.

  1. Hbim Challenge among the Paradigm of Complexity, Tools and Preservation: the Basilica DI Collemaggio 8 Years after the Earthquake (l'aquila)

    NASA Astrophysics Data System (ADS)

    Brumana, R.; Della Torre, S.; Oreni, D.; Previtali, M.; Cantini, L.; Barazzetti, L.; Franchi, A.; Banfi, F.

    2017-08-01

    In December 2012 ENIservizi (the Italian multi-national energy agency operating in many countries), after the Earthquake that occurred in April 2009, decided to undertake the project `Re-start from Collemaggio' with the aim of giving new hope to the L'Aquila community, funding around 14 million Euro to restore the Basilica di Collemaggio. The Superintendence Office carried on the restoration project with the scientific support of the Università degli Studi de L'Aquila and the Università La Sapienza di Roma, under the coordination of the Politecnico di Milano. ENIservizi, aware of the BIM potential in the complex building and infrastructure domain in the world, required an advanced HBIM from the laser scanner and photogrammetric surveying to support the diagnostic analysis, the design project, the tender and the restoration itself, today still on course. Plans and vertical sections were delivered (2012) starting from the surveying campaigns (February and June 2013), together with the first HBIM advancement from the end of 2012 in support of the preliminary-definitive-executive steps of the restoration design project (2013-14-15). Five years later, this paper tries to make a synthesis of the different lessons learnt, in addition to the positive and critical aspects relating HBIM feasibility, sustainability and usefulness to the challenging restoration work. In particular, the Collemaggio BIM experience anticipated the new Italian Public Procurement Legislation (D.Lgs 50/2016, Nuovo Codice degli Appalti pubblici) aligned with to the EUPPD 24/2014: the EU Directive on Public Procurement asked all the 28 EU countries to adopt building informative modelling by February 2016 in order to support the whole LCM (Life Cycle Management), starting from the project and the intervention, through rewarding scores or mandatory regulations. Many analyses foresees to save from around 5% to 15% of the overall investment by adopting mature BIM (Level 3 to 5), particularly 4D remotely controlled BIM in support of the LCM, as in the case of maintenance and management process. The tender for Basilica restoration was published in 2015: the process was not developed enough to introduce selective criteria based on BIM adoption by the Construction Industry due to the lack of legislation at that time and the lack of BIM skills among the companies. Nevertheless ENIservizi also separately funded aside the HBIM of the Basilica to tackle an advanced BIM able to address decision-making processes in the heritage domain among the different actors: to support operators, architects, structural engineers, economic computation, construction site management and restoration, the theoretical and practical approach adopted by the HBIM, overcame the current logic based on sequential LoD (from simplex to complex, from the preliminary to the executive design) that is typical of new constructions in favour of a complex LoD approach that could guarantee management of the richness, unicity and multiplicity of each component and the maximum degree of knowledge in order to derive the decisions from the starting phases of the project. On the lesson learnt from this experience, the process of updating the current codification criteria (UNI11337-2009) was started with a draft proposal stimulating a debate for the future of HBIM adoption.

  2. Permanent downhole fiber optic pressure and temperature monitoring during CO2 injection

    NASA Astrophysics Data System (ADS)

    Schmidt-Hattenberger, C.; Moeller, F.; Liebscher, A.; Koehler, S.

    2009-04-01

    Permanent downhole monitoring of pressure and temperature, ideally over the entire length of the injection string, is essential for any smooth and safe CO2 injection within the framework of geological CO2 storage: i) To avoid fracturing of the cap-rock, a certain, site dependent pressure threshold within the reservoir should not be exceeded; ii) Any CO2 phase transition within the injection string, i.e. either condensation or evaporation, should be avoided. Such phase transitions cause uncontrolled and undetermined P-T regimes within the injection string that may ultimately result in a shut-in of the injection facility; and iii) Precise knowledge of the P and T response of the reservoir to the CO2 injection is a prerequisite to any reservoir modeling. The talk will present first results from our permanent downhole P-T monitoring program from the Ketzin CO2 storage test site (CO2SINK). At Ketzin, a fiber Bragg grating pressure sensor has been installed at the end of the injection string in combination with distributed temperature profiling over the entire length (about 550 m) of the string for continuous P-T monitoring during operation. Such fiber optic monitoring technique is used by default in the oil and gas industry but has not yet been applied as standard on a long-term routine mode for CO2 injection. Pressure is measured every 5 seconds with a resolution of < 1 bar. The data are later processed by user-defined program. The temperature logs along the injection string are measured every 3 minutes with a spatial resolution of one meter and with a temperature resolution of about 0.1°C. The long-term stability under full operational conditions is currently under investigation. The main computer of the P-T system operates as a stand-alone data-acquisition unit, and is connected with a secure intranet in order to ensure remote data access and system maintenance. The on-line measurements are displayed on the operator panel of the injection facility for direct control. The monitoring program started already prior to CO2 injection and runs since 6 months without any fatal errors. The recorded data cover the pre-injection well-testing phase, the initial injection phase as well as several shut-in and re-start phases during routine injection. Especially during the initial and re-start phases the monitoring results significantly optimized and improved the operation of the injection facility in terms of injection rate and injection temperature. Due to the high qualitative and also quantitative resolution of this technique even shortest-term transient disturbances of the reservoir and injection regime could be monitored as they may occur due to fluid sampling or logging in neighboring wells. Such short-term transient effects are normally overlooked using non-permanent monitoring techniques. On the long-term perspective, this monitoring technique will also support the control of CO2 injection tubing integrity, which is a prerequisite for any secure long-lasting CO2 injection and storage.

  3. The Landscape of Prek-12 Engineering Online Resources for Teachers: Global Trends

    ERIC Educational Resources Information Center

    Bagiati, Aikaterini; Yoon, So Yoon; Evangelou, Demetra; Magana, Alejandra; Kaloustian, Garene; Zhu, Jiabin

    2015-01-01

    Background: The newly formed discipline of engineering education is addressing the need to (a) enhance STEM education for precollege students and (b) identify optimum ways to introduce engineering content starting, perhaps, from the early ages. Introducing engineering at the Prekindergarten through 12th grade (PreK-12) education level requires…

  4. Quantification of the fungal fraction released from various preloaded fibrous filters during a simulated ventilation restart.

    PubMed

    Morisseau, K; Joubert, A; Le Coq, L; Andres, Y

    2017-05-01

    This study aimed to demonstrate that particles, especially those associated with fungi, could be released from fibrous filters used in the air-handling unit (AHU) of heating, ventilation and air-conditioning (HVAC) systems during ventilation restarts. Quantification of the water retention capacity and SEM pictures of the filters was used to show the potential for fungal proliferation in unused or preloaded filters. Five fibrous filters with various particle collection efficiencies were studied: classes G4, M5, M6, F7, and combined F7 according to European standard EN779:2012. Filters were clogged with micronized rice particles containing the fungus Penicillium chrysogenum and then incubated for three weeks at 25°C and 90% relative humidity. The results indicated that the five clogged tested filters had various fungal growth capacities depending on their water retention capacity. Preloaded filters were subjected to a simulated ventilation restart in a controlled filtration device to quantify that the fraction of particles released was around 1% for the G4, 0.1% for the M5 and the M6, and 0.001% for the F7 and the combined F7 filter. The results indicate that the likelihood of fungal particle release by low efficiency filters is significantly higher than by high efficiency filters. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. 14 CFR 135.83 - Operating information required.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the following procedures: (1) Before starting engines; (2) Before takeoff; (3) Cruise; (4) Before... controls. (3) Engine inoperative procedures. (4) Any other emergency procedures necessary for safety. ...

  6. 14 CFR 135.83 - Operating information required.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the following procedures: (1) Before starting engines; (2) Before takeoff; (3) Cruise; (4) Before... controls. (3) Engine inoperative procedures. (4) Any other emergency procedures necessary for safety. ...

  7. 14 CFR 135.83 - Operating information required.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the following procedures: (1) Before starting engines; (2) Before takeoff; (3) Cruise; (4) Before... controls. (3) Engine inoperative procedures. (4) Any other emergency procedures necessary for safety. ...

  8. 14 CFR 135.83 - Operating information required.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... the following procedures: (1) Before starting engines; (2) Before takeoff; (3) Cruise; (4) Before... controls. (3) Engine inoperative procedures. (4) Any other emergency procedures necessary for safety. ...

  9. 14 CFR 135.83 - Operating information required.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... the following procedures: (1) Before starting engines; (2) Before takeoff; (3) Cruise; (4) Before... controls. (3) Engine inoperative procedures. (4) Any other emergency procedures necessary for safety. ...

  10. Planetary Protection Progress of Hayabusa2 and Its Piggyback PROCYON: Launch, Earth Swingby and Outbound Cruising Phases

    NASA Astrophysics Data System (ADS)

    Yano, Hajime; Yoshikawa, Makoto; Sarli, Bruno; Ozaki, Naoya; Funase, Ryu; Tsuda, Yuichi; Chujo, Toshihiro; Ariu, Kaito

    2016-07-01

    Hayabusa-2 is Japan's second asteroid sample return mission which was successfully launched into the planned Earth departure trajectory with the H-IIA rocket on December 3rd, 2014, together with a group of its interplanetary piggyback micro- spacecraft, including the PROCYON(Proximate Object Close flYby with Optical Navigation)spacecraft, the world's first 50 kg-class deep space micro-spacecraft developed by the University of Tokyo and the Japan Aerospace Exploration Agency. The Hayabusa-2 spacecraft will go to Rug, a C-type NEO, and attempt surface investigations with daughter rovers (MINERVA-II series and MASCOT), artificial impact cratering experiment (SCI) and both surface and sub-surface sampling (Sampler) in 2018-2019 and plans to return to the Earth in December 2020. The PROCYON mission objective was to demonstrate a micro-spacecraft bus technology for deep space exploration and proximity flyby to asteroids performing optical measurements. Both of the above missions were fully evaluated by the COSPAR Planetary Protection Panel at the dedicated COSPAR colloquium and scientific assembly in 2014 and the COSPAR PPP has endorsed the Category-2 for their outbound trajectories and the non-restricted Earth return for the inbound trajectory of Hayabusa-2. As a part of the fulfillments of the Category-2 classification, both spacecraft must be compliant with the COSPAR PPP requirements of non-impact probability to Mars since they would have enough energy to reach and beyond the orbit of Mars, due to the Earth swing-by and ion engine operations for their outbound cruising. As for the Hayabusa-2 spacecraft, it successfully performed its Earth gravity assist in December 2015, resulting on accurate orbit determination for the post-swing-by orbit to be ready to restart the ion engine operation. Thus the non-impact probability to Mars did not change from the estimate given by Chujo, et al. (2015). As for the PROCYON spacecraft after the completion of the bus system demonstration, it started deep space maneuver using the ion engines so that the spacecraft would be injected into an asteroid flyby trajectory via the Earth swing-by scheduled in December 2015. However, malfunction of the PROCYON high voltage system in the thruster occurred in March 2015, and the operation of the ion thruster stopped after 223 hours of successful continuous operation. Due to this anomaly, PROCYON gave up reaching its final destination (NEO "2000 DP107"); thus it now can be said that the spacecraft will never impact on Mars. In this paper, we summarize the mission status of the both projects in terms of the COSPAR PPP perspectives.

  11. 40 CFR 1033.150 - Interim provisions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... carryover data from an engine family that we previously considered available for the configuration, the...) Idle controls. A locomotive equipped with an automatic engine stop/start system that was originally... small manufacturers under § 1033.901. (e) Producing switch locomotives using certified nonroad engines...

  12. 40 CFR 1033.150 - Interim provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... carryover data from an engine family that we previously considered available for the configuration, the...) Idle controls. A locomotive equipped with an automatic engine stop/start system that was originally... small manufacturers under § 1033.901. (e) Producing switch locomotives using certified nonroad engines...

  13. 40 CFR 1033.150 - Interim provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... carryover data from an engine family that we previously considered available for the configuration, the...) Idle controls. A locomotive equipped with an automatic engine stop/start system that was originally... small manufacturers under § 1033.901. (e) Producing switch locomotives using certified nonroad engines...

  14. Assessment of transit supportive land use for new starts projects : FY 1999 new starts report. A supplement to the fiscal year 1999 report on funding levels and allocations of funds for transit major capital investments

    DOT National Transportation Integrated Search

    1998-11-01

    FTA assessed and rated the Transit Supportive Existing Land Use and Future Patterns of 30 candidate New Starts projects, in preliminary engineering and final design, documented in the FY 1999 New Starts Report. These land use assessments (30) examine...

  15. Biomedical engineering and society: policy and ethics.

    PubMed

    Flexman, J A; Lazareck, L

    2007-01-01

    Biomedical engineering impacts health care and contributes to fundamental knowledge in medicine and biology. Policy, such as through regulation and research funding, has the potential to dramatically affect biomedical engineering research and commercialization. New developments, in turn, may affect society in new ways. The intersection of biomedical engineering and society and related policy issues must be discussed between scientists and engineers, policy-makers and the public. As a student, there are many ways to become engaged in the issues surrounding science and technology policy. At the University of Washington in Seattle, the Forum on Science Ethics and Policy (FOSEP, www.fosep.org) was started by graduate students and post-doctoral fellows interested in improving the dialogue between scientists, policymakers and the public and has received support from upper-level administration. This is just one example of how students can start thinking about science policy and ethics early in their careers.

  16. Vegetation survey of PEN Branch wetlands

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Not Available

    A survey was conducted of vegetation along Pen Branch Creek at Savannah River Site (SRS) in support of K-Reactor restart. Plants were identified to species by overstory, understory, shrub, and groundcover strata. Abundance was also characterized and richness and diversity calculated. Based on woody species basal area, the Pen Branch delta was the most impacted, followed by the sections between the reactor and the delta. Species richness for shrub and groundcover strata were also lowest in the delta. No endangered plant species were found. Three upland pine areas were also sampled. In support of K Reactor restart, this report summarizesmore » a study of the wetland vegetation along Pen Branch. Reactor effluent enters Indian Grove Branch and then flows into Pen Branch and the Pen Branch Delta.« less

  17. The Scalable Checkpoint/Restart Library

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moody, A.

    The Scalable Checkpoint/Restart (SCR) library provides an interface that codes may use to worite our and read in application-level checkpoints in a scalable fashion. In the current implementation, checkpoint files are cached in local storage (hard disk or RAM disk) on the compute nodes. This technique provides scalable aggregate bandwidth and uses storage resources that are fully dedicated to the job. This approach addresses the two common drawbacks of checkpointing a large-scale application to a shared parallel file system, namely, limited bandwidth and file system contention. In fact, on current platforms, SCR scales linearly with the number of compute nodes.more » It has been benchmarked as high as 720GB/s on 1094 nodes of Atlas, which is nearly two orders of magnitude faster thanthe parallel file system.« less

  18. Advanced transportation system studies technical area 3: Alternate propulsion subsystem concepts, volume 3

    NASA Technical Reports Server (NTRS)

    Levak, Daniel

    1993-01-01

    The objective of this contract was to provide definition of alternate propulsion systems for both earth-to-orbit (ETO) and in-space vehicles (upper stages and space transfer vehicles). For such propulsion systems, technical data to describe performance, weight, dimensions, etc. was provided along with programmatic information such as cost, schedule, needed facilities, etc. Advanced technology and advanced development needs were determined and provided. This volume separately presents the various program cost estimates that were generated under three tasks: the F-1A Restart Task, the J-2S Restart Task, and the SSME Upper Stage Use Task. The conclusions, technical results, and the program cost estimates are described in more detail in Volume 1 - Executive Summary and in individual Final Task Reports.

  19. Advanced Transportation System Studies. Technical Area 3: Alternate Propulsion Subsystems Concepts. Volume 3; Program Cost Estimates

    NASA Technical Reports Server (NTRS)

    Levack, Daniel J. H.

    2000-01-01

    The objective of this contract was to provide definition of alternate propulsion systems for both earth-to-orbit (ETO) and in-space vehicles (upper stages and space transfer vehicles). For such propulsion systems, technical data to describe performance, weight, dimensions, etc. was provided along with programmatic information such as cost, schedule, needed facilities, etc. Advanced technology and advanced development needs were determined and provided. This volume separately presents the various program cost estimates that were generated under three tasks: the F- IA Restart Task, the J-2S Restart Task, and the SSME Upper Stage Use Task. The conclusions, technical results , and the program cost estimates are described in more detail in Volume I - Executive Summary and in individual Final Task Reports.

  20. Recurrent Streptococcus agalactiae Toxic Shock Syndrome Triggered by a Tumor Necrosis Factor-α Inhibitor

    PubMed Central

    Yoshida, Masataka; Takazono, Takahiro; Tashiro, Masato; Saijo, Tomomi; Morinaga, Yoshitomo; Yamamoto, Kazuko; Nakamura, Shigeki; Imamura, Yoshifumi; Miyazaki, Taiga; Sawai, Toyomitsu; Nishino, Tomoya; Izumikawa, Koichi; Yanagihara, Katsunori; Mukae, Hiroshi; Kohno, Shigeru

    2016-01-01

    Streptococcal toxic shock syndrome caused by group B streptococcus (GBS) is a rare, but lethal disease. We experienced a 45-year-old woman with pustular psoriasis who developed toxic shock-like syndrome during infliximab treatment. Surprisingly, similar episodes recurred three times in one year with restarting of infliximab treatments. In the third episode, GBS were detected in blood, urine, and vaginal secretion cultures. These episodes of shock syndrome were possibly due to GBS. To the best of our knowledge, this is the first case report of recurrent streptococcal toxic shock syndrome possibly caused by GBS which was induced by anti-TNF-α inhibitor therapy. The restarting of biological agents in patients with a history of toxic shock syndrome should therefore be avoided as much as possible. PMID:27803422

Top