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Sample records for kletychen otgovor sled

  1. SLED phenomenology: curvature vs. volume

    NASA Astrophysics Data System (ADS)

    Niedermann, Florian; Schneider, Robert

    2016-03-01

    We assess the question whether the SLED (Supersymmetric Large Extra Dimensions) model admits phenomenologically viable solutions with 4D maximal symmetry. We take into account a finite brane width and a scale invariance (SI) breaking dilaton-brane coupling, both of which should be included in a realistic setup. Provided that the brane tension and the microscopic size of the brane take generic values set by the fundamental bulk Planck scale, we find that either the 4D curvature or the size of the extra dimensions is unacceptably large. Since this result is independent of the dilaton-brane couplings, it provides the biggest challenge to the SLED program.

  2. Nonholonomic diffusion of a stochastic sled.

    PubMed

    Jung, Peter; Marchegiani, Giampiero; Marchesoni, Fabio

    2016-01-01

    A sled is a stylized mechanical model of a system which is constrained to move in space in a specific orientation, i.e., in the direction of the runners of the sled or a blade. The negation of motion transverse to the runners renders the sled a nonholonomic mechanical system. In this paper we report on the unexpected and fascinating richness of the dynamics of such a sled if it is subject to random forces. Specifically we show that the ensuing random dynamics is characterized by relatively smooth sections of motion interspersed by episodes of persistent tumbling (change of orientation) and sharp reversals resembling the random walks of bacterial cells. In the presence of self-propulsion, the diffusivity of the sled can be enhanced and suppressed depending on the directionality and strength of the propulsive force. PMID:26871121

  3. Nonholonomic diffusion of a stochastic sled

    NASA Astrophysics Data System (ADS)

    Jung, Peter; Marchegiani, Giampiero; Marchesoni, Fabio

    2016-01-01

    A sled is a stylized mechanical model of a system which is constrained to move in space in a specific orientation, i.e., in the direction of the runners of the sled or a blade. The negation of motion transverse to the runners renders the sled a nonholonomic mechanical system. In this paper we report on the unexpected and fascinating richness of the dynamics of such a sled if it is subject to random forces. Specifically we show that the ensuing random dynamics is characterized by relatively smooth sections of motion interspersed by episodes of persistent tumbling (change of orientation) and sharp reversals resembling the random walks of bacterial cells. In the presence of self-propulsion, the diffusivity of the sled can be enhanced and suppressed depending on the directionality and strength of the propulsive force.

  4. Issues Associated with a Hypersonic Maglev Sled

    NASA Technical Reports Server (NTRS)

    Haney, Joseph W.; Lenzo, J.

    1996-01-01

    Magnetic levitation has been explored for application from motors to transportation. All of these applications have been at velocities where the physics of the air or operating fluids are fairly well known. Application of Maglev to hypersonic velocities (Mach greater than 5) presents many opportunities, but also issues that require understanding and resolution. Use of Maglev to upgrade the High Speed Test Track at Holloman Air Force Base in Alamogordo New Mexico is an actual hypersonic application that provides the opportunity to improve test capabilities. However, there are several design issues that require investigation. This paper presents an overview of the application of Maglev to the test track and the issues associated with developing a hypersonic Maglev sled. The focus of this paper is to address the issues with the Maglev sled design, rather than the issues with the development of superconducting magnets of the sled system.

  5. 50 CFR 36.36 - Sled dogs and household pets.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Sled dogs and household pets. The general trespass provisions of 50 CFR 26.21 shall not apply to household pets and sled, work, or pack dogs under the direct control of their owners or handlers, but such... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Sled dogs and household pets....

  6. 50 CFR 36.36 - Sled dogs and household pets.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Sled dogs and household pets. The general trespass provisions of 50 CFR 26.21 shall not apply to household pets and sled, work, or pack dogs under the direct control of their owners or handlers, but such... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Sled dogs and household pets....

  7. 50 CFR 36.36 - Sled dogs and household pets.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Sled dogs and household pets. The general trespass provisions of 50 CFR 26.21 shall not apply to household pets and sled, work, or pack dogs under the direct control of their owners or handlers, but such... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Sled dogs and household pets....

  8. 50 CFR 36.36 - Sled dogs and household pets.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Sled dogs and household pets. The general trespass provisions of 50 CFR 26.21 shall not apply to household pets and sled, work, or pack dogs under the direct control of their owners or handlers, but such... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Sled dogs and household pets....

  9. 50 CFR 36.36 - Sled dogs and household pets.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Sled dogs and household pets. The general trespass provisions of 50 CFR 26.21 shall not apply to household pets and sled, work, or pack dogs under the direct control of their owners or handlers, but such... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Sled dogs and household pets....

  10. [Sled dog racing and animal welfare aspects].

    PubMed

    Schminke, A; Möbius, G

    1998-03-01

    Transport, housing and the dimensions of strain during training and race are important aspects of animal welfare. The race veterinarian has a great responsibility. He is responsible for the treatment of injured dogs and he has to give advice on all medical and animal welfare questions. The presence of the veterinarian during the entire race is very important. These veterinarians should have special knowledge of small animals and of sled dogs in particular. There should be health checks of sled dogs before and after racing similar to horse sport tournaments. PMID:9581387

  11. Molecular sled sequences are common in mammalian proteins

    PubMed Central

    Xiong, Kan; Blainey, Paul C.

    2016-01-01

    Recent work revealed a new class of molecular machines called molecular sleds, which are small basic molecules that bind and slide along DNA with the ability to carry cargo along DNA. Here, we performed biochemical and single-molecule flow stretching assays to investigate the basis of sliding activity in molecular sleds. In particular, we identified the functional core of pVIc, the first molecular sled characterized; peptide functional groups that control sliding activity; and propose a model for the sliding activity of molecular sleds. We also observed widespread DNA binding and sliding activity among basic polypeptide sequences that implicate mammalian nuclear localization sequences and many cell penetrating peptides as molecular sleds. These basic protein motifs exhibit weak but physiologically relevant sequence-nonspecific DNA affinity. Our findings indicate that many mammalian proteins contain molecular sled sequences and suggest the possibility that substantial undiscovered sliding activity exists among nuclear mammalian proteins. PMID:26857546

  12. Molecular sled sequences are common in mammalian proteins.

    PubMed

    Xiong, Kan; Blainey, Paul C

    2016-03-18

    Recent work revealed a new class of molecular machines called molecular sleds, which are small basic molecules that bind and slide along DNA with the ability to carry cargo along DNA. Here, we performed biochemical and single-molecule flow stretching assays to investigate the basis of sliding activity in molecular sleds. In particular, we identified the functional core of pVIc, the first molecular sled characterized; peptide functional groups that control sliding activity; and propose a model for the sliding activity of molecular sleds. We also observed widespread DNA binding and sliding activity among basic polypeptide sequences that implicate mammalian nuclear localization sequences and many cell penetrating peptides as molecular sleds. These basic protein motifs exhibit weak but physiologically relevant sequence-nonspecific DNA affinity. Our findings indicate that many mammalian proteins contain molecular sled sequences and suggest the possibility that substantial undiscovered sliding activity exists among nuclear mammalian proteins. PMID:26857546

  13. Gouge initiation in high-velocity rocket sled testing

    SciTech Connect

    Tachau, R.D.M.; Trucano, T.G.; Yew, C.H.

    1994-07-01

    A model is presented which describes the formation of surface damage ``gouging`` on the rails that guide rocket sleds. An unbalanced sled can randomly cause a very shallow-angle, oblique impact between the sled shoe and the rail. This damage phenomenon has also been observed in high-velocity guns where the projectile is analogous to the moving sled shoe and the gun barrel is analogous to the stationary rail. At sufficiently high velocity, the oblique impact will produce a thin hot layer of soft material on the contact surfaces. Under the action of a normal moving load, the soft layer lends itself to an anti-symmetric deformation and the formation of a ``hump`` in front of the moving load. A gouge is formed when this hump is overrun by the sled shoe. The phenomenon is simulated numerically using the CTH strong shock physics code, and the results are in good agreement with experimental observation.

  14. Reference PMHS Sled Tests to Assess Submarining.

    PubMed

    Uriot, Jérôme; Potier, Pascal; Baudrit, Pascal; Trosseille, Xavier; Petit, Philippe; Richard, Olivier; Compigne, Sabine; Masuda, Mitsutoshi; Douard, Richard

    2015-11-01

    Sled tests focused on pelvis behavior and submarining can be found in the literature. However, they were performed either with rigid seats or with commercial seats. The objective of this study was to get reference tests to assess the submarining ability of dummies in more realistic conditions than on rigid seat, but still in a repeatable and reproducible setup. For this purpose, a semi-rigid seat was developed, which mimics the behavior of real seats, although it is made of rigid plates and springs that are easy to reproduce and simulate with an FE model. In total, eight PMHS sled tests were performed on this semirigid seat to get data in two different configurations: first in a front seat configuration that was designed to prevent submarining, then in a rear seat configuration with adjusted spring stiffness to generate submarining. All subjects sustained extensive rib fractures from the shoulder belt loading. No pelvis fractures and no submarining were observed in the front seat configuration, but two subjects sustained lumbar vertebrae fractures. In the rear seat configuration, all subjects sustained pelvic fractures and demonstrated submarining. Corridors were constructed for the external forces and the PMHS kinematics. They are provided in this paper as new reference tests to assess the biofidelity of human surrogates in different configurations that either result in submarining or do not. In future, it is intended to analyze further seat and restraint system configurations to be able to define a submarining predictor. PMID:26660745

  15. Speeding up biomolecular interactions by molecular sledding

    SciTech Connect

    Turkin, Alexander; Zhang, Lei; Marcozzi, Alessio; Mangel, Walter F.; Herrmann, Andreas; van Oijen, Antoine M.

    2015-10-07

    In numerous biological processes associations involve a protein with its binding partner, an event that is preceded by a diffusion-mediated search bringing the two partners together. Often hindered by crowding in biologically relevant environments, three-dimensional diffusion can be slow and result in long bimolecular association times. Moreover, the initial association step between two binding partners often represents a rate-limiting step in biotechnologically relevant reactions. We also demonstrate the practical use of an 11-a.a. DNA-interacting peptide derived from adenovirus to reduce the dimensionality of diffusional search processes and speed up associations between biological macromolecules. We functionalize binding partners with the peptide and demonstrate that the ability of the peptide to one-dimensionally diffuse along DNA results in a 20-fold reduction in reaction time. We also show that modifying PCR primers with the peptide sled enables significant acceleration of standard PCR reactions.

  16. Speeding up biomolecular interactions by molecular sledding

    DOE PAGESBeta

    Turkin, Alexander; Zhang, Lei; Marcozzi, Alessio; Mangel, Walter F.; Herrmann, Andreas; van Oijen, Antoine M.

    2015-10-07

    In numerous biological processes associations involve a protein with its binding partner, an event that is preceded by a diffusion-mediated search bringing the two partners together. Often hindered by crowding in biologically relevant environments, three-dimensional diffusion can be slow and result in long bimolecular association times. Moreover, the initial association step between two binding partners often represents a rate-limiting step in biotechnologically relevant reactions. We also demonstrate the practical use of an 11-a.a. DNA-interacting peptide derived from adenovirus to reduce the dimensionality of diffusional search processes and speed up associations between biological macromolecules. We functionalize binding partners with the peptidemore » and demonstrate that the ability of the peptide to one-dimensionally diffuse along DNA results in a 20-fold reduction in reaction time. We also show that modifying PCR primers with the peptide sled enables significant acceleration of standard PCR reactions.« less

  17. 7. SHOWING METHOD OF SLEDDING WIND CABLE DOWN YAKI TRAIL ...

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

    7. SHOWING METHOD OF SLEDDING WIND CABLE DOWN YAKI TRAIL TO THE BRIDGE, WEIGHT OF CABLE AND DRUM APPROXIMATELY 2200 POUNDS - Kaibab Trail Suspension Bridge, Spanning Colorado River, Grand Canyon, Coconino County, AZ

  18. The BATSE SLED: The problem and the correction

    NASA Technical Reports Server (NTRS)

    Lestrade, John Patrick

    1991-01-01

    The Burst And Transient Source Experiment (BATSE) has been in space for 4 months and, by anyone's reckoning, is performing better than even the most optimistic pre-flight predictions. That doesn't mean there haven't been some small surprises. Because of the discreteness of gamma-ray energies available to us in pre-flight testing, we could not subject the instrument to the continuous distribution of energies it now sees in space. Therefore, it was not until the beginning of mission operations that a small non-linearity was discovered in the low energy region of the SPD spectra. The nickname for this depression is the SLED (Spectroscopy Low-Energy Depression). Sample spectra for module 6 at two gains (1X and 0.4X) are given. Note that the position of the sled is gain-independent in channel space. A further study on a non-flight module discovered the cause lay in the spectroscopy analog electronics. Above a certain energy threshold, the digital signal from the SPEC-FAST2 discriminator causes, in effect, an extra small amount of charge to be added to the SHER analog input. The laboratory measurements of SHER output energy as a function of input energy are presented. The change of slope at the point of the SLED results in narrower bin widths for the channels in that region. The SLED is approximately 5 channels wide. It should be mentioned that below the SLED and for many decades above the SLED the response is extremely linear. The proposed fix was to move the lower straight line up to match the extrapolation of the upper straight line, shown by the dotted line. In effect, this means reassigning channel numbers. All channel edges lower than the SLED are moved a fixed amount to higher channel numbers. Channel edges in the SLED are moved a different amount depending on their position. The latter obviously results in narrower channel widths in energy space.

  19. Rocket Sled Propelled Testing of a Supersonic Inflatable Aerodynamic Decelerator

    NASA Technical Reports Server (NTRS)

    Meacham, Michael B.; Kennett, Andrew; Townsend, Derik J.; Marti, Benjamin

    2013-01-01

    Decelerators (IADs) have traditionally been tested in wind tunnels. As the limitations of these test facilities are reached, other avenues must be pursued. The IAD being tested is a Supersonic IAD (SIAD), which attaches just aft of the heatshield around the perimeter of an entry body. This 'attached torus' SIAD is meant to improve the accuracy of landing for robotic class missions to Mars and allow for potentially increased payloads. The SIAD Design Verification (SDV) test aims to qualify the SIAD by applying a targeted aerodynamic load to the vehicle. While many test architectures were researched, a rocket sled track was ultimately chosen to be the most cost effective way to achieve the desired dynamic pressures. The Supersonic Naval Ordnance Research Track (SNORT) at the Naval Air Warfare Center Weapons Division (NAWCWD) China Lake is a four mile test track, traditionally used for warhead and ejection seat testing. Prior to SDV, inflatable drag bodies have been tested on this particular track. Teams at Jet Propulsion Laboratory (JPL) and NAWCWD collaborate together to design and fabricate one of the largest sleds ever built. The SDV sled is comprised of three individual sleds: a Pusher Sled which holds the solid booster rockets, an Item Sled which supports the test vehicle, and a Camera Sled that is pushed in front for in-situ footage and measurements. The JPL-designed Test Vehicle has a full-scale heatshield shape and contains all instrumentation and inflation systems necessary to inflate and test a SIAD. The first campaign that is run at SNORT tested all hardware and instrumentation before the SIAD was ready to be tested. For each of the three tests in this campaign, the number of rockets and top speed was increased and the data analyzed to ensure the hardware is safe at the necessary accelerations and aerodynamic loads.

  20. SLEDs and Swept Source Laser Technology for OCT

    NASA Astrophysics Data System (ADS)

    Duelk, Marcus; Hsu, Kevin

    EXALOS offers broadband and high-power superluminescent light-emitting diodes (SLEDs) and high-speed wavelength-swept lasers, covering various visible and near-infrared wavelength regions (390-1,700 nm). These diverse wavelengths are realized in different semiconductor material systems such as GaN, GaAs, or InP. Those light sources are used in various fields such as navigation, optical coherence tomography (OCT), metrology, sensing, and microscopy. Detailed discussions on SLED characteristics and key swept-source OCT system design parameters are presented.

  1. 7. ROCKET SLED ON DECK OF TEST STAND 15. Photo ...

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

    7. ROCKET SLED ON DECK OF TEST STAND 1-5. Photo no. "6085, G-EAFB-16 SEP 52." Looking south to machine shop. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-5, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

  2. Noise assessment of the rocket sled test track operation at Jolloman AFB, New Mexico. Final report

    SciTech Connect

    Shaffer, W.J.

    1988-10-01

    This report presents the results of noise data measurements of the Holloman AFB rocket-sled test-track operations. Impulse and community noise measurements were made to determine the impact of the rocket-sled noise on the surrounding community. A worst case sled run was measured and used to determine that the rocket sled has very little impact on the community for a worst-case rocket-sled run and little or no impact for the majority of the runs. Recommendations were made to limit the number of people exposed to the rocket sled noise and require test-track personnel to wear hearing protection. Sonic-boom measurement equipment should be purchased to document all sonic booms created by the rocket sled.

  3. Adjustable Shock Test Sled for Haversine Pulses at 250 fps

    SciTech Connect

    Troy Hartwig; Brent Hower; Aaron Seaholm

    2008-05-05

    New test requirements were developed by Sandia National Laboratory to simulate a regime of shock testing not previously performed at the Kansas City Plant operated by Honeywell Federal Manufacturing & Technologies. These environments were unique in that they involved amplitude of shock >1000g with relatively long pulse durations (greater 5 ms but less than 10 ms) and involved velocity changes up to 235 ft/sec. Ten months were available to develop, design, manufacture and prove-in this new capability. We designed a new shock sled to deliver this new family of shock environments in a laboratory test. The performance range of the new sled includes five specific shocks (1000 g – 8 ms, 1300 - 6 ms, 1500 g – 5.4 ms, 1950 g – 6 ms, 2250 g – 5.4 ms; all haversine shaped), and it also incorporates adjustability to accommodate new shocks within this range. These shock environments result in velocity changes ranging from 160 fps to 250 fps. The test sled accommodates test articles weighing up to 20 lbs and measuring up to 10” along any axis.

  4. Sonic boom measurements from accelerating supersonic tracked sleds

    NASA Technical Reports Server (NTRS)

    Reed, J. W.

    1974-01-01

    Supersonic sled tests on the Sandia 1524-m (5000-ft) track generate sonic booms of sufficient intensity to allow some airblast measurements at distance scales not obtained from wind tunnel or flight tests. During acceleration, an emitted curved boom wave propagates to a caustic, or focus. Detailed measurements around these caustics may help to clarify the overpressure magnification which can occur from real aircraft operations. Six fixed pressure gages have been operated to document the general noise field, and a mobile array of twelve gages.

  5. A Transformational Curriculum Model: A Wilderness Travel Adventure Dog Sledding in Temagami.

    ERIC Educational Resources Information Center

    Leckie, Linda

    1996-01-01

    Personal narrative links elements of a dog sledding trip with the transformational curriculum model as applied to outdoor education. Describes the physical, mental, and spiritual challenges of a seven-day winter camping and dog sledding trip, during which students learned responsibility through experience and natural consequences and realized the…

  6. Sea-Ice Thickness Monitoring from Sensor Equipped Inuit Sleds

    NASA Astrophysics Data System (ADS)

    Rodwell, Shane; Jones, Bryn; Wilkinson, Jeremy

    2013-04-01

    A novel instrumentation package capable of measuring sea-ice thickness autonomously has been designed for long-term deployment upon the dog drawn sleds of the indigenous peoples of the Arctic. The device features a range of sensors that have been integrated with an electromagnetic induction device. These include a global positioning system, temperature sensor, tilt meter and accelerometer. Taken together, this system is able to provide accurate (+/-5cm) measurements of ice thickness with spatio-temporal resolution ranging from 1m to 5m every second. Autonomous data transmission capability is provided via GSM, inspired by the fact that many of the coastal communities in Greenland possess modern cell-phone infrastructure, enabling an inexpensive means of data-retrieval. Such data is essential in quantifying the sea-ice mass balance; given that existing satellite based systems are unable to measure ice-thickness directly. Field-campaign results from a prototype device, deployed in the North West of Greenland during three consecutive seasons, have demonstrated successful proof-of-concept when compared to data provided by ice mass balance (IMB) stations provided at fixed positions along the route of the sled. This project highlights not only the use of novel polar technology, but how opportunistic deployment using an existing roving platform (Inuit sledges) can provide economical, yet highly valuable, data for instrumentation development.

  7. Evaluation of plasma inflammatory cytokine concentrations in racing sled dogs.

    PubMed

    von Pfeil, Dirsko J F; Cummings, Bethany P; Loftus, John P; Levine, Corri B; Mann, Sabine; Downey, Robert L; Griffitts, Caroline; Wakshlag, Joseph J

    2015-12-01

    In human athletes significant changes in cytokine concentrations secondary to exercise have been observed. This prospective study evaluated the effect of a multi-day stage sled dog race on plasma concentrations of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-α), interleukin-2 (IL-2), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-10 (IL-10). Samples from 20 dogs were harvested prior to and on days 2 and 8 of an 8-day race. Exercise resulted in significantly decreased TNF-α and IL-8 as well as increases of MCP-1, IL-6, and IL-10 concentrations (P-value between 0.01 and < 0.0001 for all parameters). The proportion of values for IL-2 that were below the detection limit increased from 40% on day 0 to 75% on day 2 and decreased on day 8 to 40% (P = 0.04). Racing sled dogs show cytokine-concentration changes that are different from those in humans. PMID:26663920

  8. SNR of swept SLEDs and swept lasers for OCT.

    PubMed

    Johnson, Bart; Atia, Walid; Flanders, Dale C; Kuznetsov, Mark; Goldberg, Brian D; Kemp, Nate; Whitney, Peter

    2016-05-16

    A back-to-back comparison of a tunable narrow-band-filtered SLED (TSLED) and a swept laser are made for OCT applications. The two sources are similar in terms of sweep speed, tuning range and coherence length. A fundamental issue with a TSLED is that the RIN is proportional to 1/linewidth, meaning that the longer the coherence length, the higher the RIN and clock jitter. We show that the TSLED has an SNR limit that causes noise streaks at points of high reflection in images. The laser, which is shot noise limited, does not exhibit this effect. We add noise terms proportional to the sample power times reference power to standard swept source SNR expressions to account for the SNR limit. PMID:27409939

  9. Energetic particle studies at Mars by SLED on Phobos 2.

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, S.; Afonin, V. V.; Gringauz, K. I.; Kecskemety, K.; Keppler, E.; Kirsch, E.; Richter, A.; Rusznyak, P.; Schwingenschuh, K.; O'Sullivan, D.; Somogyi, A. J.; Szabo, L.; Thompson, A.; Varga, A.; Yeroshenko, Ye.; Witte, M.

    1992-09-01

    A preliminary overview of particle records obtained by the SLED instrument on Phobos 2, Feb-Mar, 1989 during Mars encounter, is presented. Data obtained while in close elliptical orbit around the planet (pericenter <900 km), in both spin and three axis stabilised mode, display evidence of energy related particle shadowing by the body of Mars. Flux enhancements, inside the magnetopause, in the approximate range 30 - 350 keV, recorded in the same general location at <900 km above Mars over an 8 day period during three consecutive elliptical orbits, are described. Possible explanations of these enhancements include the presence of quasi-trapped radiation at the planet and the detection of the propagation of accelerated particles along the boundary of the magnetopause from the day to the night side of Mars.

  10. Energetic particle studies at Mars by SLED on PHOBOS 2

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, S.; Afonin, V. V.; Gringauz, K. I.; Kecskemety, K.; Keppler, E.; Kirsch, E.; Richter, A.; Rusznyak, P.; Schwingenschuh, K.; O'Sullivan, D.

    1992-09-01

    Data recorded by the SLED instruments on Phobos 2 while it was in the first four elliptical orbits and during 114 circular orbits about Mars (February-March, 1989) are presented. Data obtained while in close elliptical orbits around the planet display evidence of energy-related particle shadowing by the body of Mars; this effect was also sometimes observed in circular orbits at an altitude of 6330 km above the planet. Possible explanations of this phenomenon include the presence of quasi-trapped radiation of Mars and the detected propagation of accelerated particles along the boundary of the magnetopause from the dayside to the nightside of the planet. In circular orbits, many significant flux enhancement events, in the range 30-200 keV, were detected adjacent to the bow shock, indicating that the spacecraft traversed strongly anisotropic jets of energetic particles, which are suggested to contain O(+) ions.

  11. Driven microswimmers on a 2D substrate: A stochastic towed sled model

    NASA Astrophysics Data System (ADS)

    Marchegiani, Giampiero; Marchesoni, Fabio

    2015-11-01

    We investigate, both numerically and analytically, the diffusion properties of a stochastic sled sliding on a substrate, subject to a constant towing force. The problem is motivated by the growing interest in controlling transport of artificial microswimmers in 2D geometries at low Reynolds numbers. We simulated both symmetric and asymmetric towed sleds. Remarkable properties of their mobilities and diffusion constants include sidewise drifts and excess diffusion peaks. We interpret our numerical findings by making use of stochastic approximation techniques.

  12. A genetic dissection of breed composition and performance enhancement in the Alaskan sled dog

    PubMed Central

    2010-01-01

    Background The Alaskan sled dog offers a rare opportunity to investigate the development of a dog breed based solely on performance, rather than appearance, thus setting the breed apart from most others. Several established breeds, many of which are recognized by the American Kennel Club (AKC), have been introduced into the sled dog population to enhance racing performance. We have used molecular methods to ascertain the constitutive breeds used to develop successful sled dog lines, and in doing so, determined the breed origins of specific performance-related behaviors. One hundred and ninety-nine Alaskan sled dogs were genotyped using 96 microsatellite markers that span the canine genome. These data were compared to that from 141 similarly genotyped purebred dog breeds. Sled dogs were evaluated for breed composition based on a variety of performance phenotypes including speed, endurance and work ethic, and the data stratified based on population structure. Results We observe that the Alaskan sled dog has a unique molecular signature and that the genetic profile is sufficient for identifying dogs bred for sprint versus distance. When evaluating contributions of existing breeds we find that the Alaskan Malamute and Siberian Husky contributions are associated with enhanced endurance; Pointer and Saluki are associated with enhanced speed and the Anatolian Shepherd demonstrates a positive influence on work ethic. Conclusion We have established a genetic breed profile for the Alaskan sled dog, identified profile variance between sprint and distance dogs, and established breeds associated with enhanced performance attributes. These data set the stage for mapping studies aimed at finding genes that are associated with athletic attributes integral to the high performing Alaskan sled dog. PMID:20649949

  13. Driven microswimmers on a 2D substrate: A stochastic towed sled model

    SciTech Connect

    Marchegiani, Giampiero; Marchesoni, Fabio

    2015-11-14

    We investigate, both numerically and analytically, the diffusion properties of a stochastic sled sliding on a substrate, subject to a constant towing force. The problem is motivated by the growing interest in controlling transport of artificial microswimmers in 2D geometries at low Reynolds numbers. We simulated both symmetric and asymmetric towed sleds. Remarkable properties of their mobilities and diffusion constants include sidewise drifts and excess diffusion peaks. We interpret our numerical findings by making use of stochastic approximation techniques.

  14. Diet of racing sled dogs affects erythrocyte depression by stress.

    PubMed

    Adkins, T O; Kronfeld, D S

    1982-09-01

    Fourteen racing huskies were matched into pairs then assigned to two diets, a commercial stress diet and an experimental diet. Proportions of protein: fat:carbohydrate on an available energy basis were 23:57:20 in a commercial stress diet and 28:69:3 in an experimental diet. The team participated in the 1979 Iditarod Trail race and was overtaken by an episode of diarrhea. Clinical signs were suggestive of parvovirus infection; high serum titers of parvo antibodies were found after the race. Blood examination showed normal levels of metabolites, electrolytes and enzymes after the race. Erythrocyte counts were depressed significantly during the race, by 15% in dogs fed an experimental diet and by 27% in those fed a commercial stress diet. Erythrocyte parameters have also become depressed during the racing season in middle distance sled dogs fed 28% protein (energy basis) but not 32 or 39%. Depressed red blood cell production has been demonstrated previously in dogs subjected to stress induced experimentally in several ways, and its restoration has been affected by dietary protein. Erythrocyte parameters may be useful indicies of the degree of stress in a dog as well as the adequacy of its protein intake during stress. PMID:17422178

  15. Switching speed effect of phase shift keying in SLED for generating high power microwaves

    NASA Astrophysics Data System (ADS)

    Xiong, Zheng-Feng; Cheng, Cheng; Yu, Jian; Chen, Huai-Bi; Ning, Hui

    2016-01-01

    SLAC energy doubler (SLED) type radio-frequency pulse compressors are widely used in large-scale particle accelerators for converting long-duration moderate-power input pulses into short-duration high-power output pulses. Phase shift keying (PSK) is one of the key components in SLED pulse compression systems. Performance of the PSK will influence the output characteristics of the SLED, such as the rise-time of the output pulse, maximal peak power gain, and energy efficiency. In this paper, a high power microwave source based on power combining and pulse compression of conventional klystrons is introduced. The effects of nonideal PSK with slow switching speed and PSK without power output during the switching process are investigated, and the experimental results with nonideal PSK agree well with the analytical results.

  16. Simultaneous processing of photographic and accelerator array data from sled impact experiment

    NASA Astrophysics Data System (ADS)

    Ash, M. E.

    1982-12-01

    A Quaternion-Kalman filter model is derived to simultaneously analyze accelerometer array and photographic data from sled impact experiments. Formulas are given for the quaternion representation of rotations, the propagation of dynamical states and their partial derivatives, the observables and their partial derivatives, and the Kalman filter update of the state given the observables. The observables are accelerometer and tachometer velocity data of the sled relative to the track, linear accelerometer array and photographic data of the subject relative to the sled, and ideal angular accelerometer data. The quaternion constraints enter through perfect constraint observations and normalization after a state update. Lateral and fore-aft impact tests are analyzed with FORTRAN IV software written using the formulas of this report.

  17. Broadband SLED-based light source (BeST-SLEDTM) and spectrometer

    NASA Astrophysics Data System (ADS)

    Yadid-Pecht, Orly; Dattner, Yonathan

    2016-03-01

    A small footprint, low power, cost effective single mode fiber coupled broadband light source and spectrometer is presented. It is based on Super Luminescent Diode (SLED) devices and a compact design enables coverage of the 1250 nm-1750 nm region with a total optical power of 50 mW at the output of the fiber. This Broad Spectrum Tunable Super Luminescent (BeST-SLEDTM) light source can operate at temperatures ranging from -40°C to 60°C, and resides in a custom designed 26-pin package. The fiber is a polarization maintaining fiber with a FC/APC connector at the output. Three variations of the BeST-SLEDTM were developed, BEST-SLED™ Bands, BeST-SLEDTM Tunable and BeST-SLEDTM FTNIR. In the Bands version six SLEDs were packaged allowing for one SLED on at a time or any combination of the SLEDs on. In the Tunable version an Acoustic Optical Tunable Filter (AOTF) was integrated into the package allowing the user to select one wavelength at a time to pass into the fiber with resolution of ~1 nm @1550nm. In the FTNIR version, a Silicon Photonic based interferometer (the Nano-SpecTM) was integrated into the package for a Fourier Transform Near Infrared based Spectrometer and light source. The BeST-SLEDTM is being used in process control applications such as steam quality measurements, oil in water, gas composition and air quality monitoring.

  18. EVALUATION OF A TIME DOMAIN REFLECTOMETRY SLED FOR MAPPING SOIL WATER CONTENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A rapid method for mapping soil water content would be valuable for agricultural and scientific applications such as precision irrigation. A sled type measurement device with a time domain reflectometer and global positioning system was evaluated for measuring soil water content following tillage. T...

  19. Effect of the coefficient of friction of a running surface on sprint time in a sled-towing exercise.

    PubMed

    Linthorne, Nicholas P; Cooper, James E

    2013-06-01

    This study investigated the effect of the coefficient of friction of a running surface on an athlete's sprint time in a sled-towing exercise. The coefficients of friction of four common sports surfaces (a synthetic athletics track, a natural grass rugby pitch, a 3G football pitch, and an artificial grass hockey pitch) were determined from the force required to tow a weighted sled across the surface. Timing gates were then used to measure the 30-m sprint time for six rugby players when towing a sled of varied weight across the surfaces. There were substantial differences between the coefficients of friction for the four surfaces (micro = 0.21-0.58), and in the sled-towing exercise the athlete's 30-m sprint time increased linearly with increasing sled weight. The hockey pitch (which had the lowest coefficient of friction) produced a substantially lower rate of increase in 30-m sprint time, but there were no significant differences between the other surfaces. The results indicate that although an athlete's sprint time in a sled-towing exercise is affected by the coefficient offriction of the surface, the relationship relationship between the athlete's rate of increase in 30-m sprint time and the coefficient of friction is more complex than expected. PMID:23898689

  20. Head Trajectories of Restrained Child Dummy in Sled Tests Over 56 kph Delta-V

    PubMed Central

    Hauschild, Hans W.

    2000-01-01

    Child restraint devices (CRDs) have been used for many years to protect children in automotive crashes. The following data was collected to find out whether current restraints would be able to pass more stringent dynamic testing at higher changes in velocity (delta-v), such as the NHTSA NCAP program or the IIHS offset barrier test, and to look at one possible misuse mode. Three basic types of CRDs were sled tested at a delta-v between 57.5 & 61.4 kph (35.7 & 38.1 mph). Data from each test are presented and compared. Comparisons are made between each seat’s sled test results and various countries’ standards. PMID:11558089

  1. The SLED instrument on the PHOBOS mission to Mars and its moons

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, Susan M. P.

    1989-09-01

    The twin-telescope particle-detector system SLED (energy range 30 keV to 30 MeV), which was built in Ireland, is briefly described. Also, an account is given of its successful performance in space, as attested by the acquisition of unique data during the 204-day cruise phase of the Phobos mission to Mars and its moons and during Mars encounter.

  2. Performance Evaluation of Child Safety Seats in Far-Side Lateral Sled Tests at Varying Speeds

    PubMed Central

    Ghati, Yoganand; Menon, Rajiv A.; Milone, Mary; Lankarani, Hamid; Oliveres, Gerardo

    2009-01-01

    Protection of children in Child Safety Seats (CSS) in side impact crashes has been a topic of recent studies. The objective of this study was to evaluate the performance of CSS in far-side impacts through a series of sled tests conducted at varying test speeds. Forty eight sled tests were conducted at three speeds (24 km/h, 29 km/h and 36 km/h), under two different CSS attachment conditions (LATCH and seat belt attached), using rear facing and forward facing CSS from four different manufacturers. Analyses were conducted to examine head retention within the CSS, velocity of the head as it passes an imaginary plane (cross over into other occupant space or door), lateral trajectory of the head and knee; head, chest and pelvis accelerations; neck and lumbar loads and moments. In addition to these parameters, the CSS were visually inspected for structural integrity after each test. Results from these sled tests highlighted the differential performance of CSS in far-side impacts. During the tests, all CSS experienced significant lateral movement irrespective of attachment type. In rear facing CSS tests, one of the designs failed as the seat disengaged from its base. In forward facing CSS tests, it was observed that the seat belt attached CSS experienced less rotational motion than the LATCH attached CSS. ATD head retention within the seat was not achieved with either CSS attachments at any speed. The findings from this study augment the current efforts to define regulatory sled setup procedure for far-side impact crashes involving children in CSS, which currently does not exist and will eventually further the protection of children in automobiles. PMID:20184846

  3. Mercury interferes with endogenous antioxidant levels in Yukon River subsistence-fed sled dogs

    NASA Astrophysics Data System (ADS)

    Dunlap, Kriya L.; Reynolds, Arleigh J.; Gerlach, S. Craig; Duffy, Lawrence K.

    2011-10-01

    Before adopting modern corn-and-grain-based western processed diets, circumpolar people had a high fat and protein subsistence diet and exhibited a low incidence of obesity, diabetes and cardiovascular disease. Some health benefits are attributable to a subsistence diet that is rich in omega-3 fatty acids and antioxidants. Pollution, both global and local, is a threat to wild foods, as it introduces contaminants into the food system. Northern indigenous people and their sled dogs are exposed to a variety of contaminants, including mercury, that accumulate in the fish and game that they consume. The sled dogs in Alaskan villages are maintained on the same subsistence foods as their human counterparts, primarily salmon, and therefore they can be used as a food systems model for researching the impact of changes in dietary components. In this study, the antioxidant status and mercury levels were measured for village sled dogs along the Yukon River. A reference kennel, maintained on a nutritionally balanced commercial diet, was also measured for comparison. Total antioxidant status was inversely correlated with the external stressor mercury.

  4. The NIWA seamount sled: An effective epibenthic sledge for sampling epifauna on seamounts and rough seafloor

    NASA Astrophysics Data System (ADS)

    Clark, Malcolm R.; Stewart, Rob

    2016-02-01

    Epibenthic sleds, sledges and dredges have been widely used for sampling deep-sea macro and megafaunal communities, providing extensive information on benthic biodiversity and distribution patterns. Different countries and institutes have developed a variety of gear types, but these are often unsuitable for sampling rough seafloor, such as seamount and ridge topography. The NIWA seamount sled, a form of epibenthic sledge, is an inexpensive yet robust and versatile sampling device used to obtain invertebrate and rock samples. It incorporates features from a number of existing designs that have produced a versatile sled that can be used on all habitats from mud through to steep and rocky seamounts. It has been used for many research surveys around New Zealand, where it has proven an efficient sampler of target fauna (large macro- and mega-benthic epifauna). Its design has also been adopted by institutes in France and China for surveying seamounts, and it is suggested it could be used as a simple standardised design for sampling seamounts internationally.

  5. High-power rf pulse compression with SLED-II at SLAC

    SciTech Connect

    Nantista, C.; Kroll, N.M.; Farkas, Z.D.; Lavine, T.L.; Menegat, A.; Ruth, R.D.; Tantawi, S.G.; Vlieks, A.E.; Wilson, P.B.

    1993-04-01

    Increasing the peak rf power available from X-band microwave tubes by means of rf pulse compression is envisioned as a way of achieving the few-hundred-megawatt power levels needed to drive a next-generation linear collider with 50--100 MW klystrons. SLED-II is a method of pulse compression similar in principal to the SLED method currently in use on the SLC and the LEP injector linac. It utilizes low-los resonant delay lines in place of the storage cavities of the latter. This produces the added benefit of a flat-topped output pulse. At SLAC, we have designed and constructed a prototype SLED-II pulse-compression system which operates in the circular TE{sub 01} mode. It includes a circular-guide 3-dB coupler and other novel components. Low-power and initial high-power tests have been made, yielding a peak power multiplication of 4.8 at an efficiency of 40%. The system will be used in providing power for structure tests in the ASTA (Accelerator Structures Test Area) bunker. An upgraded second prototype will have improved efficiency and will serve as a model for the pulse compression system of the NLCTA (Next Linear Collider Test Accelerator).

  6. Upgrade of the SLAC SLED II Pulse Compression System Based on Recent High Power Tests

    SciTech Connect

    Vlieks, A.E.; Fowkes, W.R.; Loewen, R.J.; Tantawi, S.G.; /SLAC

    2011-09-06

    In the Next Linear Collider (NLC) it is expected that the high power rf components be able to handle peak power levels in excess of 400 MW. We present recent results of high power tests designed to investigate the RF breakdown limits of the X-band pulse compression system used at SLAC. (SLED-II). Results of these tests show that both the TE{sub 01}-TE{sub 10} mode converter and the 4-port hybrid have a maximum useful power limit of 220-250 MW. Based on these tests, modifications of these components have been undertaken to improve their peak field handling capability. Results of these modifications will be presented. As part of an international effort to develop a new 0.5-1.5 TeV electron-positron linear collider for the 21st century, SLAC has been working towards a design, referred to as 'The Next Linear Collider' (NLC), which will operate at 11.424 GHz and utilize 50-75 MW klystrons as rf power sources. One of the major challenges in this design, or any other design, is how to generate and efficiently transport extremely high rf power from a source to an accelerator structure. SLAC has been investigating various methods of 'pulse compressing' a relatively wide rf pulse ({ge} 1 {mu}s) from a klystron into a narrower, but more intense, pulse. Currently a SLED-II pulse compression scheme is being used at SLAC in the NLC Test Accelerator (NLCTA) and in the Accelerator Structures Test Area (ASTA) to provide high rf power for accelerator and component testing. In ASTA, a 1.05 {mu}s pulse from a 50 MW klystron was successfully pulse compressed to 205 MW with a pulse width of 150 ns. Since operation in NLC will require generating and transporting rf power in excess of 400 MW it was decided to test the breakdown limits of the SLED-II rf components in ASTA with rf power up to the maximum available of 400 MW. This required the combining of power from two 50 MW klystrons and feeding the summed power into the SLED-II pulse compressor. Results from this experiment demonstrated

  7. Impact of Harness Attachment Point on Kinetics and Kinematics During Sled Towing.

    PubMed

    Bentley, Ian; Atkins, Steve J; Edmundson, Christopher J; Metcalfe, John; Sinclair, Jonathan K

    2016-03-01

    Resisted sprint training is performed in a horizontal direction and involves similar muscles, velocities, and ranges of motion (ROM) to those of normal sprinting. Generally, sleds are attached to the athletes through a lead (3 m) and harness; the most common attachment points are the shoulder or waist. At present, it is not known how the different harness point's impact on the kinematics and kinetics associated with sled towing (ST). The aim of the current investigation was to examine the kinetics and kinematics of shoulder and waist harness attachment points in relation to the acceleration phase of ST. Fourteen trained men completed normal and ST trials, loaded at 10% reduction of sprint velocity. Sagittal plane kinematics from the trunk, hip, knee, and ankle were measured, together with stance phase kinetics (third footstrike). Kinetic and kinematic parameters were compared between harness attachments using one-way repeated-measures analysis of variance. The results indicated that various kinetic differences were present between the normal and ST conditions. Significantly greater net horizontal mean force, net horizontal impulses, propulsive mean force, and propulsive impulses were measured (p < 0.05). Interestingly, the waist harness also led to greater net horizontal impulse when compared with the shoulder attachment (p < 0.001). In kinematic terms, ST conditions significantly increased peak flexion in hip, knee, and ankle joints compared with the normal trials (p < 0.05). Results highlighted that the shoulder harness had a greater impact on trunk and knee joint kinematics when compared with the waist harness (p < 0.05). In summary, waist harnesses seem to be the most suitable attachment point for the acceleration phase of sprinting. Sled towing with these attachments resulted in fewer kinematic alterations and greater net horizontal impulse when compared with the shoulder harness. Future research is necessary in order to explore the long-term adaptations of

  8. High-J CO Sleds in Nearby Infrared Bright Galaxies Observed By Herschel/PACS

    NASA Astrophysics Data System (ADS)

    Mashian, N.; Sturm, E.; Sternberg, A.; Janssen, A.; Hailey-Dunsheath, S.; Fischer, J.; Contursi, A.; González-Alfonso, E.; Graciá-Carpio, J.; Poglitsch, A.; Veilleux, S.; Davies, R.; Genzel, R.; Lutz, D.; Tacconi, L.; Verma, A.; Weiß, A.; Polisensky, E.; Nikola, T.

    2015-04-01

    We report the detection of far-infrared (FIR) CO rotational emission from nearby active galactic nuclei (AGNs) and starburst galaxies, as well as several merging systems and Ultra-Luminous Infrared Galaxies (ULIRGs). Using the Herschel Photodetector Array Camera and Spectrometer (PACS), we have detected transitions in the Jupp = 14-30 range. The PACS CO data obtained here provide the first reference of well-sampled FIR extragalactic CO spectral line energy distributions (SLEDs) for this range. We find a large range in the overall SLED shape, even among galaxies of similar type, demonstrating the uncertainties in relying solely on high-J CO diagnostics to characterize the excitation source of a galaxy. Combining our data with low-J line intensities taken from the literature, we present a CO ratio-ratio diagram and discuss its value in distinguishing excitation sources and physical properties of the molecular gas. The position of a galaxy on such a diagram is less a signature of its excitation mechanism, than an indicator of the presence of warm, dense molecular gas. We then quantitatively analyze the CO emission from a subset of the detected sources with single-component and two-component large velocity gradient (LVG) radiative transfer models to fit the CO SLEDs. From these fits we derive the molecular gas mass and the corresponding CO-to-H2 conversion factor, {{α }CO}, for each respective source. For the ULIRGs we find α values in the canonical range 0.4- 5M⊙ (K km s-1 pc2)-1, while for the other objects, α varies between 0.2 and 14. Finally, we compare our best-fit LVG model results with previous studies of the same galaxies and comment on any differences. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

  9. Technical Advisory Team (TAT) report on the rocket sled test accident of October 9, 2008.

    SciTech Connect

    Stofleth, Jerome H.; Dinallo, Michael Anthony; Medina, Anthony J.

    2009-01-01

    This report summarizes probable causes and contributing factors that led to a rocket motor initiating prematurely while employees were preparing instrumentation for an AIII rocket sled test at SNL/NM, resulting in a Type-B Accident. Originally prepared by the Technical Advisory Team that provided technical assistance to the NNSA's Accident Investigation Board, the report includes analyses of several proposed causes and concludes that the most probable source of power for premature initiation of the rocket motor was the independent battery contained in the HiCap recorder package. The report includes data, evidence, and proposed scenarios to substantiate the analyses.

  10. Digital synchroballistic schlieren camera for high-speed photography of bullets and rocket sleds

    NASA Astrophysics Data System (ADS)

    Buckner, Benjamin D.; L'Esperance, Drew

    2013-08-01

    A high-speed digital streak camera designed for simultaneous high-resolution color photography and focusing schlieren imaging is described. The camera uses a computer-controlled galvanometer scanner to achieve synchroballistic imaging through a narrow slit. Full color 20 megapixel images of a rocket sled moving at 480 m/s and of projectiles fired at around 400 m/s were captured, with high-resolution schlieren imaging in the latter cases, using conventional photographic flash illumination. The streak camera can achieve a line rate for streak imaging of up to 2.4 million lines/s.

  11. Magnetic Shadowing of High Energy Ions at Mars, Comparisons Between SLED/Phobos-2 Observations and Simulations

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, S. M.; Kallio, E. J.; Jarvinen, R.; Afonin, V.

    2011-12-01

    Energetic particle data recorded by the SLED instrument aboard Phobos-2 while in circular orbit about Mars in March, 1989 showed the presence of magnetic shadowing. A 3-D, self-consistent, hybrid model (HYB-Mars) supplemented by test particle simulations was developed to study the response of the Martian plasma environment to solar disturbances and to interpret, in particular, the SLED observations. The magnetic and electric fields, as well as the properties of high energy ions, present at Mars under conditions of extreme solar disturbance can be derived from HYB-Mars. Our initial study [McKenna-Lawlor et al., EPS 2011, in press] showed that the HYB-Mars model predicted an already well-documented plasma phenomenon at the planet, namely the "solar wind-flow shadowing", identified in measurements of the ASPERA (plasma) experiment aboard Phobos-2. Furthermore, the HYB-Mars model predicted the occurrence of magnetic shadowing which is qualitatively similar to that recorded by SLED. Also, the simulations suggested that the configuration of the magnetic shadow depends on the pertaining solar wind density and velocity, and on the magnitude and direction of the interplanetary magnetic field. This study presents a more detailed investigation where upstream plasma and magnetic field conditions input to the HYB-Mars model come from measurements made aboard Phobos-2 contemporaneously with the SLED observations. In this way it is possible to realistically match the upstream interplanetary conditions with the configuration of the magnetic shadow recorded at various energies in the SLED data. One-to-one comparisons between the SLED observations and the simulated high energy H+ fluxes will be presented in this context and similarities and differences between the observations and the simulations discussed.

  12. In-vivo Kinematics of the Cervical Spine in Frontal Sled Tests

    PubMed Central

    Dehner, Christoph; Schick, Sylvia; Hell, Wolfram; Richter, Peter; Kraus, Michael; Kramer, Michael

    2013-01-01

    The description of cervical spine motion and the risk to sustain a cervical spine injury in traffic accidents is mainly based on rear-end collisions. The knowledge about frontal collisions is comparable low. Therefore the objective of this exploratory study was, to describe the in-vivo cervical spine motion and acceleration during simulated frontal sled collisions and to identify sequences of motion in which the risk of injury is increased. A frontal collision with a speed change of 10.2km/h was simulated in a sled test with ten volunteers. Cervical spine kinematics was assessed by the simultaneous analysis of the angular head motion and acceleration as well as the simultaneous analysis of the relative motion and acceleration between the head and the first thoracic vertebral body. The motion sequence was divided into five phases. The combination of peak values of the angular head acceleration to ventral and the relative horizontal head acceleration to dorsal between the time period of 90ms and 110ms (early flexion phase) included – potential injury generating – shear forces. Although a hyperflexion (late rebound phase) as injury pattern didn’t occur, dorsal soft tissue injuries due to eccentric muscle-sprain could not be ruled out completely. In conclusion the study showed under simulated test conditions that during the early flexion phase and the late rebound phase, acceleration and movement pattern occur that could lead to cervical spine injuries. PMID:23618481

  13. Low energy charged particles in near Martian space from the SLED and LET experiments aboard the Phobos-2 spacecraft

    NASA Astrophysics Data System (ADS)

    Afonin, V. V.; McKenna-Lawlor, S. M. P.; Erdos, G.; Gringauz, K. I.; Keppler, E.; Kecskemety, K.; Kirsch, E.; Marsden, R. G.; Richter, A. K.; Riedler, W.; Schwingenschuh, K.; Somogyi, A.; O'Sullivan, D.; Szabo, L.; Thompson, A.; Varga, A.; Wenzel, K.-P.; Witte, M.; Yeroshenko, Ye.; Zelenyi, L.

    1991-02-01

    The charged particle detector SLED on the Phobos-2 spacecraft has recorded, during a number of circular orbits about Mars, significant fluxes of ions with energies up to 200 keV in close spatial association with the Martian bow shock. The observed characteristics of these enhancements suggest that different shock acceleration mechanisms were operative in producing individual events.

  14. Electron-Beam Switches For A High Peak Power Sled-II Pulse Compressor

    SciTech Connect

    Hirshfield, Jay, L.

    2015-12-02

    Omega-P demonstrated triggered electron-beam switches on the L=2 m dual-delay-line X-band pulse compressor at Naval Research Laboratory (NRL). In those experiments, with input pulses of up to 9 MW from the Omega-P/NRL X-band magnicon, output pulses having peak powers of 140-165 MW and durations of 16-20 ns were produced, with record peak power gains M of 18-20. Switch designs are described based on the successful results that should be suitable for use with the existing SLAC SLED-II delay line system, to demonstrate C=9, M=7, and n>>78%, yielding 173ns compressed pulses with peak powers up to 350MW with input of a single 50-MW.

  15. Pediatric Extracorporeal Membrane Oxygenation Transport by EC-145 With a Custom-Built Sled.

    PubMed

    Holt, Philip L; Hodge, Ashley B; Ratliff, Todd; Frazier, W Joshua; Ohnesorge, David; Gee, Samantha W

    2016-01-01

    Indications for the use of extracorporeal membrane oxygenation (ECMO) in pediatrics has expanded beyond the initial historic treatment of neonates with respiratory failure. Patients with severe refractory cardiopulmonary failure may benefit from ECMO support until the primary insult has subsided or been treated. More recently, ECMO has been used by some centers as a bridge to transplant for irreversible organ failure. Nationwide Children's Hospital is a referral center that supports the use of ECMO as a bridge to transplant and is able to provide transport services for ECMO patients referred for transplant evaluation. In this report, we describe our design of a unique, custom-built sled designed specifically for the EC-145 helicopter to transport pediatric ECMO patients to our institution. This report is the first, to our knowledge, to describe the safe and successful transport of a pediatric ECMO patient in an EC-145 helicopter. PMID:27255881

  16. SNR of swept SLEDs and swept lasers for OCT (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Johnson, Bart C.; Atia, Walid; Flanders, Dale; Kuznetsov, Mark; Goldberg, Brian; Kemp, Nate; Whitney, Peter

    2016-03-01

    A back-to-back comparison of a tunable narrow-band SLED (TSLED) and a swept laser are made for OCT applications. Both are 1310 nm sources sweeping at 50 kHz over a 100 nm tuning range and have similar coherence lengths. The TSLED consists of a seed SOA and two amplification SOAs. The ASE is filtered twice by a tunable MEMS Fabry Perot in a polarization multiplexed double-pass arrangement on either side of the middle SOA. This allows very long coherence lengths to be achieved. A fundamental issue with a SLED is that the RIN is proportional to 1/Linewidth, meaning that the longer the coherence length, the higher the RIN. High RIN also leads to increased clock jitter. Most swept source SNR calculations assume that the noise is independent of the amplitude of the signal light: The higher the signal, the higher the SNR. We show that in the case of the TSLED, that the high signal RIN and clock jitter give rise to additional noises that scale with signal power. This leads to an SNR limit in the case of the TSLED: The higher the signal, the higher the noise, so the SNR reaches a limit. While the TSLED has respectable sensitivity, the SNR limit causes noise streaks in an image where the A-line has a high reflectivity point. The laser, which is shot noise limited, does not exhibit this effect. This is illustrated with SNR data and side-by-side images taken with the two sources.

  17. Effects of bracing on human kinematics in low-speed frontal sled tests.

    PubMed

    Beeman, Stephanie M; Kemper, Andrew R; Madigan, Michael L; Duma, Stefan M

    2011-12-01

    Continued development of computational models and biofidelic anthropomorphic test devices (ATDs) necessitates further analysis of the effects of bracing on an occupant's biomechanical response in automobile collisions. A total of 20 dynamic sled tests were performed, 10 low (2.5 g, Δv = 4.8 kph) and 10 medium severity (5.0 g, Δv = 9.7 kph), with five male human volunteers of approximately 50th percentile male height and weight. Each volunteer was exposed to two impulses at each severity, one relaxed and one braced prior to the impulse. A Vicon motion analysis system, 12 MX-T20 2 megapixel cameras, was used to quantify subject 3D kinematics (±1 mm) (1 kHz). Excursions of select anatomical regions were normalized to their respective initial positions and compared by test condition. At the low severity, bracing significantly reduced (p < 0.05) the forward excursion of the knees, hips, elbows, shoulders, and head (average 35-70%). At the medium severity, bracing significantly reduced (p < 0.05) the forward excursion of the elbows, shoulders, and head (average 36-69%). Although not significant, bracing at the medium severity considerably reduced the forward excursion of the knees and hips (average 18-26%). This study illustrates that bracing has a significant influence on the biomechanical response of human occupants in frontal sled tests and provides novel biomechanical data that can be used to refine and validate computational models and ATDs used to assess injury risk in automotive collisions. PMID:21870249

  18. Effects of a synbiotic on fecal quality, short-chain fatty acid concentrations, and the microbiome of healthy sled dogs

    PubMed Central

    2013-01-01

    Background Sled dogs commonly suffer from diarrhea. Although multiple etiologies exist there are limited field studies using synbiotics as a supplement to prevent or treat diarrhea. The objective of this study was to examine alterations in fecal quality, short-chain fatty acids (SCFA), and the fecal microbiome in two groups of training sled dogs fed a synbiotic or microcrystalline cellulose placebo. Twenty clinically healthy training sled dogs randomized into two cohorts (9 synbiotic-fed, 8 placebo-fed) for a 6 week prospective study were examined. Fecal pH and fecal short chain fatty acid (SCFA) concentrations were measured and tag-encoded FLX 16S rDNA amplicon pyrosequencing (bTEFAP) and quantitative real-time PCR were performed at baseline (10 d prior to the study) and after 2 weeks of treatment with a total treatment time of 6 weeks. Fecal scores for all dogs were assessed at baseline and every day for 6 wk after initiation of treatment. Results Alterations in the fecal microbiome were observed with a significant rise in Lactobacillaceae in the synbiotic group (P = 0.004) after 2 wk of treatment. A positive correlation was found between Lactobacillaceae and overall butyrate concentration (R = 0.62, p = 0.011) in all dogs. After 5 wk of treatment, there was an improved fecal score and fewer days of diarrhea (Χ2 = 5.482, P = 0.019) in the dogs given synbiotic, which coincided with a presumed contagious outbreak shared by all dogs in the study. Conclusions Use of this synbiotic results in an increase in presumed beneficial bacterial flora of the host colon which was associated with a decrease in the prevalence of diarrhea in training sled dogs. PMID:24313995

  19. Magnetic shadowing of high energy ions at Mars: Comparison of SLED/Phobos-2 observations and hybrid model simulations

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, S.; Kallio, E.; Jarvinen, R.; Alho, M.; Afonin, V. V.

    2011-10-01

    Energetic particle data recorded by the SLED instrument aboard Phobos-2 while in circular orbit about Mars in March, 1989 showed the presence of magnetic shadowing. A 3-D, self-consistent, hybrid model (HYB-Mars) supplemented by test particle simulations has been developed to study the response of the Martian plasma environment to the solar disturbances concerned and to interpret the SLED observations. During Extreme Solar Events, the magnetic and electric fields as well as the properties of high energy ions present at Mars can be derived from HYB-Mars. It has already been shown [1] that the hybrid modeling results in magnetic shadowing which is qualitatively similar to that recorded by SLED at Mars while demonstrating in addition that the size of the shadow decreases with the energy of the ions in the range analyzed (50 keV to 3.2 MeV). In this presentation the initial qualitative study outlined above has been extended to provide a more quantitative analysis by comparing the observed and the simulated fluxes of high energy ions at Mars during Extreme Flaring.

  20. Molecular sled is an eleven-amino acid vehicle facilitating biochemical interactions via sliding components along DNA

    PubMed Central

    Mangel, Walter F.; McGrath, William J.; Xiong, Kan; Graziano, Vito; Blainey, Paul C.

    2016-01-01

    Recently, we showed the adenovirus proteinase interacts productively with its protein substrates in vitro and in vivo in nascent virus particles via one-dimensional diffusion along the viral DNA. The mechanism by which this occurs has heretofore been unknown. We show sliding of these proteins along DNA occurs on a new vehicle in molecular biology, a ‘molecular sled' named pVIc. This 11-amino acid viral peptide binds to DNA independent of sequence. pVIc slides on DNA, exhibiting the fastest one-dimensional diffusion constant, 26±1.8 × 106 (bp)2 s−1. pVIc is a ‘molecular sled,' because it can slide heterologous cargos along DNA, for example, a streptavidin tetramer. Similar peptides, for example, from the C terminus of β-actin or NLSIII of the p53 protein, slide along DNA. Characteristics of the ‘molecular sled' in its milieu (virion, nucleus) have implications for how proteins in the nucleus of cells interact and imply a new form of biochemistry, one-dimensional biochemistry. PMID:26831565

  1. A Sled-Mounted Vibroseis Seismic Source for Geological Studies in Antarctica

    NASA Astrophysics Data System (ADS)

    Speece, M. A.; Luyendyk, B. P.; Harwood, D. M.; Powell, R. D.; Wilson, D. S.; Pekar, S. F.; Tulaczyk, S. M.; Rack, F. R.

    2013-12-01

    Given the success of recent vibrator seismic source (vibroseis) tests in Antarctica, we propose the purchase of a large vibroseis for dedicated use by United States Antarctic Program (USAP) projects in Antarctica. Long seismic reflection profiles across Antarctica can be accomplished efficiently by pulling a sled-mounted vibrator that in turn pulls a snow streamer of gimbaled geophones. A baseplate or pad in the center of the sled will be lowered to the ground and support most of the weight of the vibrator assembly while an actuator vibrates the ground at each source location. The vibroseis will be moved to remote locations using over-ice/snow traverses given the increased reliance on traversing for supplying remote sites in Antarctica. Total vibrator hold-down weight when fully assembled will be ~66,000 lbs. Other design features include a 475 HP Caterpillar C15 diesel engine for the hydraulic power unit. The new vibrator will use an INOVA P-wave vibrator system: new Model PLS-362 actuator with up to 60,000 lbs of peak force and frequency limit of 5 Hz to 250Hz. Antarctic research objectives that could be impacted by the use of a vibrator include: (1) mapping of sub-ice stratigraphic sequences for drilling for paleoclimate information, e.g. the deep sedimentary basins of West Antarctica (Ross and Ronne-Filchner Ice Shelves and related divides); (2) correlating offshore and onshore seismic data and complementing airborne geophysical surveys to help determine Antarctica's geologic history; (3) identifying ice-bedrock interface properties and exploring grounding-line processes for ice dynamics; (4) exploring subglacial lakes and water-routing systems; and, (5) investigating the physical properties of ice sheets. An Antarctic Vibroseis Advisory Committee (AVAC) will promote the use of the vibroseis capability among Antarctic geophysical, geological, glaciological and related scientists and groups by encouraging and facilitating the development and submission of

  2. Occupant kinematics in low-speed frontal sled tests: Human volunteers, Hybrid III ATD, and PMHS.

    PubMed

    Beeman, Stephanie M; Kemper, Andrew R; Madigan, Michael L; Franck, Christopher T; Loftus, Stephen C

    2012-07-01

    A total of 34 dynamic matched frontal sled tests were performed, 17 low (2.5g, Δv=4.8kph) and 17 medium (5.0g, Δv=9.7kph), with five male human volunteers of approximately 50th percentile height and weight, a Hybrid III 50th percentile male ATD, and three male PMHS. Each volunteer was exposed to two impulses at each severity, one relaxed and one braced prior to the impulse. A total of four tests were performed at each severity with the ATD and one trial was performed at each severity with each PMHS. A Vicon motion analysis system, 12 MX-T20 2 megapixel cameras, was used to quantify subject 3D kinematics (±1mm) (1kHz). Excursions of select anatomical regions were normalized to their respective initial positions and compared by test condition and between subject types. The forward excursions of the select anatomical regions generally increased with increasing severity. The forward excursions of relaxed human volunteers were significantly larger than those of the ATD for nearly every region at both severities. The forward excursions of the upper body regions of the braced volunteers were generally significantly smaller than those of the ATD at both severities. Forward excursions of the relaxed human volunteers and PMHSs were fairly similar except the head CG response at both severities and the right knee and C7 at the medium severity. The forward excursions of the upper body of the PMHS were generally significantly larger than those of the braced volunteers at both severities. Forward excursions of the PMHSs exceeded those of the ATD for all regions at both severities with significant differences within the upper body regions. Overall human volunteers, ATD, and PMHSs do not have identical biomechanical responses in low-speed frontal sled tests but all contribute valuable data that can be used to refine and validate computational models and ATDs used to assess injury risk in automotive collisions. PMID:22342960

  3. Misuse Study of Latch Attachment: A Series of Frontal Sled Tests

    PubMed Central

    Menon, Rajiv; Ghati, Yoganand

    2007-01-01

    This study was initiated to quantify the effects of the misuse in LATCH lower webbing. In the short period since the implementation of the LATCH system several cases of potential misuses have been reported. A series of sled tests in frontal impact mode were conducted with various misuse conditions (loose attachment of LATCH lower webbing, misrouting of LATCH lower webbing and child seat back inclination) for both forward and rearward facing child safety seats (FFCSS and RFCSS). Results from these tests are compared and discussed with that of the standard test with no misuse and showed that as the slack in the lower LATCH webbing increased, ATD injury measures exceeded the limits. The FFCSS tests in the reclined condition yielded lower injury values for all except the chest G’s when compared to the standard upright test. In the misrouting tests the ATD kinematics depended on the routing pivot point, the lower the pivot point the better the ATD kinematics. Similar findings were also observed in the RFCSS tests. The use of top tether with the FFCSS substantially improved the performance of the Hybrid III 3 year old ATD in spite of misuse conditions and the injury values were lower than the corresponding tests with no top tether. The effective reduction was 37% in the HIC values, 6% in the chest G’s, 30% in the head excursion, 22 % in the knee excursion and finally 37 % reduction in the Nij values. PMID:18184489

  4. Misuse study of latch attachment: a series of frontal sled tests.

    PubMed

    Menon, Rajiv; Ghati, Yoganand

    2007-01-01

    This study was initiated to quantify the effects of the misuse in LATCH lower webbing. In the short period since the implementation of the LATCH system several cases of potential misuses have been reported. A series of sled tests in frontal impact mode were conducted with various misuse conditions (loose attachment of LATCH lower webbing, misrouting of LATCH lower webbing and child seat back inclination) for both forward and rearward facing child safety seats (FFCSS and RFCSS). Results from these tests are compared and discussed with that of the standard test with no misuse and showed that as the slack in the lower LATCH webbing increased, ATD injury measures exceeded the limits. The FFCSS tests in the reclined condition yielded lower injury values for all except the chest G's when compared to the standard upright test. In the misrouting tests the ATD kinematics depended on the routing pivot point, the lower the pivot point the better the ATD kinematics. Similar findings were also observed in the RFCSS tests. The use of top tether with the FFCSS substantially improved the performance of the Hybrid III 3 year old ATD in spite of misuse conditions and the injury values were lower than the corresponding tests with no top tether. The effective reduction was 37% in the HIC values, 6% in the chest G's, 30% in the head excursion, 22 % in the knee excursion and finally 37 % reduction in the Nij values. PMID:18184489

  5. Energetic protons at Mars: interpretation of SLED/Phobos-2 observations by a kinetic model

    NASA Astrophysics Data System (ADS)

    Kallio, E.; McKenna-Lawlor, S.; Alho, M.; Jarvinen, R.; Dyadechkin, S.; Afonin, V. V.

    2012-11-01

    Mars has neither a significant global intrinsic magnetic field nor a dense atmosphere. Therefore, solar energetic particles (SEPs) from the Sun can penetrate close to the planet (under some circumstances reaching the surface). On 13 March 1989 the SLED instrument aboard the Phobos-2 spacecraft recorded the presence of SEPs near Mars while traversing a circular orbit (at 2.8 RM). In the present study the response of the Martian plasma environment to SEP impingement on 13 March was simulated using a kinetic model. The electric and magnetic fields were derived using a 3-D self-consistent hybrid model (HYB-Mars) where ions are modelled as particles while electrons form a massless charge neutralizing fluid. The case study shows that the model successfully reproduced several of the observed features of the in situ observations: (1) a flux enhancement near the inbound bow shock, (2) the formation of a magnetic shadow where the energetic particle flux was decreased relative to its solar wind values, (3) the energy dependency of the flux enhancement near the bow shock and (4) how the size of the magnetic shadow depends on the incident particle energy. Overall, it is demonstrated that the Martian magnetic field environment resulting from the Mars-solar wind interaction significantly modulated the Martian energetic particle environment.

  6. Evaluating the physical demands when using sled-type stair descent devices to evacuate mobility-limited occupants from high-rise buildings.

    PubMed

    Lavender, Steven A; Mehta, Jay P; Hedman, Glenn E; Park, Sanghyun; Reichelt, Paul A; Conrad, Karen M

    2015-09-01

    The physical demands on evacuators were investigated when using different types of sled-type stair descent devices designed for the emergency evacuation of high rise buildings. Twelve firefighters used six sled-type stair descent devices during simulated evacuations. The devices were evaluated under two staircase width conditions (1.12, and 1.32 m). Dependent measures included electromyographic (EMG) data, heart rates, Borg Scale ratings, and descent velocities. All stair descent speeds were below those reported during pedestrian egress trials. With the exception of the inflatable device, the devices operated by two evacuators had higher descent speeds than those operated by a single evacuator. High friction materials under the sleds facilitated control and reduced the muscle demands on stairs but increased physical demands on the landings. Usability assessments found devices with shorter overall lengths had fewer wall contacts on the landing, and handles integrated in the straps were preferred by the evacuators. PMID:25959322

  7. The low energy particle detector sled (~30 keV-3.2 MeV) and its performance on the phobos mission to mars and its moons

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, S.; Afonin, V. V.; Gringauz, K. I.; Keppler, E.; Kirsch, E.; Richter, A.; Witte, M.; O'Sullivan, D.; Thompson, A.; Somogyi, A. J.; Szabo, L.; Varga, A.

    1990-05-01

    A low energy particle detector system (SLED) is described which was designed to measure the flux densities of electrons and ions in the energy range from ~30 keV to a few MeV in (a) the varying solar aspect angles and temperatures pertaining during the Cruise Phase of the Phobos Mission and (b) in the low temperature environment (reaching -25° C) pertaining during Mars Encounter. Representative data illustrating the excellent functioning of SLED during both phases of the mission are presented.

  8. Computer simulation and sled test validation of a powerbase wheelchair and occupant subjected to frontal crash conditions.

    PubMed

    Bertocci, G E; Szobota, S; Hobson, D A; Digges, K

    1999-06-01

    The Americans with Disabilities Act (ADA) has led to an increased number of wheelchair users seeking transportation services. Many of these individuals are unable to transfer to a vehicle and are instead required to travel seated in their wheelchairs. Unfortunately, wheelchairs are not typically designed with the same occupant protection features as motor vehicle seats, and wheelchair seated occupants may be at higher risk for injury in a crash. To study the effects of crash level forces on wheelchairs and their occupants, it is useful to simulate crash conditions using computer modeling. This study has used a dynamic lumped mass crash simulator, in combination with sled impact testing, to develop a model of a secured commercial powerbase and restrained occupant subjected to a 20 g/30 mph frontal motor vehicle crash. Time histories profiles of simulation-generated wheelchair kinematics, occupant accelerations, tiedown forces and occupant restraint forces were compared to sled impact testing for model validation. Validation efforts for this model were compared to validation results found acceptable for the ISO/SAE surrogate wheelchair model. This wheelchair-occupant simulation model can be used to investigate wheelchair crash response or to evaluate the influence of various factors on occupant crash safety. PMID:10391594

  9. An SNP within the Angiotensin-Converting Enzyme Distinguishes between Sprint and Distance Performing Alaskan Sled Dogs in a Candidate Gene Analysis

    PubMed Central

    Huson, Heather J.; Byers, Alexandra M.; Runstadler, Jonathan

    2011-01-01

    The Alaskan sled dog offers a unique mechanism for studying the genetics of elite athletic performance. They are a group of mixed breed dogs, comprised of multiple common breeds, and a unique breed entity seen only as a part of the sled dog mix. Alaskan sled dogs are divided into 2 primary groups as determined by their racing skills. Distance dogs are capable of running over 1000 miles in 10 days, whereas sprint dogs run much shorter distances, approximately 30 miles, but in faster times, that is, 18–25 mph. Finding the genes that distinguish these 2 types of performers is likely to illuminate genetic contributors to human athletic performance. In this study, we tested for association between polymorphisms in 2 candidate genes; angiotensin-converting enzyme (ACE) and myostatin (MSTN) and enhanced speed and endurance performance in 174 Alaskan sled dogs. We observed 81 novel genetic variants within the ACE gene and 4 within the MSTN gene, including a polymorphism within the ACE gene that significantly (P value 2.38 × 10−5) distinguished the sprint versus distance populations. PMID:21846742

  10. Whole-body kinematic and dynamic response of restrained PMHS in frontal sled tests.

    PubMed

    Forman, Jason; Lessley, David; Kent, Richard; Bostrom, Ola; Pipkorn, Bengt

    2006-11-01

    The literature contains a wide range of response data describing the biomechanics of isolated body regions. Current data for the validation of frontal anthropomorphic test devices and human body computational models lack, however, a detailed description of the whole-body response to loading with contemporary restraints in automobile crashes. This study presents data from 14 frontal sled tests describing the physical response of postmortem human surrogates (PMHS) in the following frontal crash environments: A) (5 tests) driver position, force-limited 3-point belt plus airbag restraint (FLB+AB), 48 km/h deltaV. B) (3 tests) passenger position, FLB+AB restraint, 48 km/h deltaV. C) (3 tests) passenger position, standard (not force-limited) 3-point belt plus air bag restraint (SB+AB), 48 km/h deltaV. D) (3 tests) passenger position, standard 3-point belt restraint (SB), 29 km/h deltaV. Reported data include x-axis and z-axis (SAE occupant reference frame) accelerations of the head, spine (upper, middle, and lower), and pelvis; rate of angular rotation of the head about y-axis; displacements of the head, upper spine, pelvis and knee relative to the vehicle buck; and deformation contours of the upper and lower chest. A variety of kinematic trends are identified across the different test conditions, including a decrease in head and thorax excursion and a change in the nature of the excursion in the driver position compared to the passenger position. Despite this increase in forward excursion when compared to the driver's side FLB+AB tests, the passenger's side FLB+AB tests resulted in greater peak thoracic (T8) x-axis accelerations (passenger's side -29 g; driver's side -22 g;) and comparable maximum chest deflection (passenger's side - 23+/-3.1% of the undeformed chest depth; driver's side - 23+/-5.6%; ). In the 48 km/h passenger's side tests, the head excursion associated with the force-limiting belt system was approximately 15% greater than that for a standard belt

  11. Kinematics and dynamics of the pelvis in the process of submarining using PMHS sled tests.

    PubMed

    Luet, Carole; Trosseille, Xavier; Drazétic, Pascal; Potier, Pascal; Vallancien, Guy

    2012-10-01

    This study focused on a better understanding and characterization of the submarining phenomenon that occurs in frontal crashes when the lap belt slides over the anterior superi or iliac spine. Submarining is the consequence of the pelvis kinematics relative to the lap belt, driven by the equilibrium of forces and moments applied to the pelvis. The study had two primary purposes; the first was to provide new PMHS data in submarining test configurations, the second was to investigate the Hybrid II and Hybrid III dummies biofidelity regarding submarining. Several Post Mortem Human Subject (PMHS) studies have been published on this subject. However, the lack of information about the occupant initial positioning and the use of car seats make it difficult to reconstruct these tests. Furthermore, the two dummies are rarely compared to PMHS in submarining test configurations. A fifteen frontal sled test campaign was carried out on two Anthropomorphic Test Devices (ATDs) and nine PMHS. The test environment was designed to be reproducible. It consisted of a rigid seat, a 2-poi nts shoulder belt and a 2-points lap belt instrumented to record their 3D forces at anchorage. The subjects were instrumented with angular sensors at the sacrum, T1 and T12 levels to record their initial angles. Kinematics was measured at these three levels by means of three accelerometers and angular velocity sensors. A PMHS positioning procedure was developed to ensure repeatability. A pre-test was performed on each subject to characterize its lumbar spine static behavior. All the subjects were CT-scanned from head to toe prior to the test. The campaign was divided into three test configurations leading to different surrogates' interaction with the environment and different kinematics. This resulted in a wider range of behaviors for the dummies evaluation. The deceleration pulse, initial lap belt angle, lap belt slack, seat pan angle and footrest position varied. The Hybrid II and Hybrid III dummies

  12. Frontal sled tests comparing rear and forward facing child restraints with 1-3 year old dummies.

    PubMed

    Sherwood, C P; Crandall, J R

    2007-01-01

    Although most countries recommend transitioning children from rear facing (RF) to forward facing (FF) child restraints at one year of age, Swedish data suggests that RF restraints are more effective. The objective of this study was to compare RF and FF orientations in frontal sled tests. Four dummies (CRABI 12 mo, Q1.5, Hybrid III 3 yr, and Q3) were used to represent children from 1 to 3 years of age. Restraint systems tested included both 1) LATCH and 2) rigid ISOFIX with support leg designs. Rear facing restraints with support legs provided the best results for all injury measures, while RF restraints in general provided the lowest chest displacements and neck loads. PMID:18184491

  13. Unusual presentation of Lisfranc fracture dislocation associated with high-velocity sledding injury: a case report and review of the literature

    PubMed Central

    Benejam, Christopher E; Potaczek, Steven G

    2008-01-01

    Introduction Lisfranc fracture dislocations of the foot are rare injuries. A recent literature search revealed no reported cases of injury to the tarsometatarsal (Lisfranc) joint associated with sledding. Case presentation A 19-year-old male college student presented to the emergency department with a Lisfranc fracture dislocation of the foot as a result of a high-velocity sledding injury. The patient underwent an immediate open reduction and internal fixation. Conclusion Lisfranc injuries are often caused by high-velocity, high-energy traumas. Careful examination and thorough testing are required to identify the injury properly. Computed tomography imaging is often recommended to aid in diagnosis. Treatment of severe cases may require immediate open reduction and internal fixation, especially if the risk of compartment syndrome is present, followed by a period of immobilization. Complete recovery may take up to 1 year. PMID:18694504

  14. Responses of the Q6/Q6s ATD Positioned in Booster Seats in the Far-Side Seat Location of Side Impact Passenger Car and Sled Tests.

    PubMed

    Tylko, Suzanne; Bohman, Katarina; Bussières, Alain

    2015-11-01

    Passenger car side impact crash tests and sled tests were conducted to investigate the influence of booster seats, near-side occupant characteristics and vehicle interiors on the responses of the Q6/Q6s child ATD positioned in the rear, far-side seating location. Data from nine side impact sled tests simulating a EuroNCAP AEMD barrier test were analyzed with data obtained from 44 side impact crash tests. The crash tests included: FMVSS 214 and IIHS MDB, moving car-to-stationary car and moving car-to-moving car. A Q6 or prototype Q6s ATD was seated on the far-side, using a variety of low and high back booster seats. Head and chest responses were recorded and ATD motions were tracked with high-speed videos. The vehicle lateral accelerations resulting from MDB tests were characterized by a much earlier and more rapid rise to peak than in tests where the bullet was another car. The near-side seating position was occupied by a Hybrid III 10-year-old ATD in the sled tests, and a rear or front facing child restraint or a 5th percentile side impact ATD in the crash tests. Head impacts occurred more frequently in vehicles where a forward facing child restraint was present behind the driver seat for both the low and high back booster seats. Pretensioners were found to reduce lateral head displacements in all sled test configurations but the greatest reduction in lateral excursion was obtained with a high back booster seat secured with LATCH and tested in combination with pretensioners. PMID:26660749

  15. Influence of sustained low-efficiency diafiltration (SLED-f) on interstitial fluid concentrations of fluconazole in a critically ill patient: Use of microdialysis.

    PubMed

    Sinnollareddy, Mahipal G; Roberts, Michael S; Lipman, Jeffrey; Peake, Sandra L; Roberts, Jason A

    2015-07-01

    Acute kidney injury is a common complication in critically ill patients, and hybrid techniques including sustained low-efficiency dialysis/diafiltration (SLED-f) are being increasingly utilised in intensive care units. Most fungal infections occur in the interstitial fluid (ISF) of tissues and successful treatment of a fungal infection relies on the ability of an antifungal agent to achieve adequate concentrations at the site of infection. Tissue distribution of antimicrobials is impaired in critically ill patients owing to a variety of disease-related physiological changes, e.g. sepsis. Fluconazole is a widely used antifungal agent used to treat Candida spp. infections in critically ill patients. The implications for ISF concentrations of enhanced elimination during renal replacement therapy have not yet been reported for fluconazole. The aim of this single-patient case report was to describe the influence of SLED-f on subcutaneous (SC) ISF concentrations of fluconazole and the implications for achieving pharmacokinetic/pharmacodynamic targets. Serial blood and ISF samples were collected at pre- and post-filter ports within the SLED-f circuit and subcutaneously inserted microdialysis probe, respectively. Fluconazole concentrations were measured using a validated chromatography method. The SC ISF-to-plasma partition coefficient of fluconazole in this patient was 0.91, indicating rapid equilibrium. SC ISF fluconazole concentrations consistently decreased after initiating SLED-f. The majority of the fluconazole was eliminated from the SC ISF as a result of redistribution. Considering the extensive tissue re-distribution of fluconazole and observed elimination from tissue compartments, higher doses may be required to treat deep-seated fungal infections. PMID:25888463

  16. Injury risk of a 6-year-old wheelchair-seated occupant in a frontal motor vehicle impact--'ANSI/RESNA WC-19' sled testing analysis.

    PubMed

    Ha, DongRan; Bertocci, Gina

    2007-09-01

    Children with disabilities are transported on a daily basis to schools and developmental facilities. When they travel, they often remain seated in their wheelchairs in vehicles. To study injury risk of pediatric wheelchair users in motor vehicle crashes, three of the same pediatric manual wheelchairs were sled impact tested with a seated Hybrid III 6-year-old ATD using a 20 g/48 km/h frontal crash pulse. The sled test results were compared to kinematic limitations and injury criteria specified in the ANSI/RESNA WC-19, FMVSS 213 and FMVSS 208. All sled test results were below the limits specified in the ANSI/RESNA WC-19 standard and FMVSS 213. All tests exceeded the N(ij) limit of 1 specified in FMVSS 208, and one test exceeded the limit of peak neck tension force. Chest deflection resulting from one of three tests was at the limit specified in FMVSS 208. Our results suggest that children with disabilities who remain seated in their wheelchairs in vehicles may be at risk of neck injury in a frontal impact motor vehicle crash. However, limitations in the biofidelity of the Hybrid III ATD neck raise concern as to the translatability of these findings to the real world. Additional studies are needed to investigate the influence of neck properties and ATD neck biofidelity on injury risk of children who travel seated in their wheelchairs. PMID:17251048

  17. Molecular sled is an eleven-amino acid vehicle facilitating biochemical interactions via sliding components along DNA

    DOE PAGESBeta

    Mangel, Walter F.; McGrath, William J.; Xiong, Kan; Graziano, Vito; Blainey, Paul C.

    2016-02-02

    Recently, we showed the adenovirus proteinase interacts productively with its protein substrates in vitro and in vivo in nascent virus particles via one-dimensional diffusion along the viral DNA. The mechanism by which this occurs has heretofore been unknown. We show sliding of these proteins along DNA occurs on a new vehicle in molecular biology, a ‘molecular sled’ named pVIc. This 11-amino acid viral peptide binds to DNA independent of sequence. pVIc slides on DNA, exhibiting the fastest one-dimensional diffusion constant, 26±1.8 × 106 (bp)2 s−1. pVIc is a ‘molecular sled,’ because it can slide heterologous cargos along DNA, for example, amore » streptavidin tetramer. Similar peptides, for example, from the C terminus of β-actin or NLSIII of the p53 protein, slide along DNA. Finally, characteristics of the ‘molecular sled’ in its milieu (virion, nucleus) have implications for how proteins in the nucleus of cells interact and imply a new form of biochemistry, one-dimensional biochemistry.« less

  18. A comparison between a child-size PMHS and the Hybrid III 6 YO in a sled frontal impact

    PubMed Central

    Lopez-Valdes, Francisco J.; Forman, Jason; Kent, Richard; Bostrom, Ola; Segui-Gomez, Maria

    2009-01-01

    As pediatric PMHS data are extremely limited, evidence of kinematic differences between pediatric ATDs and live humans comes from comparison of laboratory data to field crash data. Despite the existence of regulations intended to prevent head injuries, these remain the most common serious injuries sustained by children in crashes. In this study, nine frontal sled tests using a Hybrid III 6YO and three tests performed with a child-size adult PMHS were compared, with focus on the kinematic responses (especially of the head) and the seatbelt forces generated during the impact. Two different restraint systems (a pretensioning, force-limiting seatbelt, and a non pretensioning force-limiting standard belt) and two different impact speeds (29 km/h and 48 km/h) were compared. Data from the PMHS were scaled using the erect sitting height of a 50th percentile 6YO and both scaled and unscaled data are presented. The ATD predicted correctly the peak values of the scaled displacements of the PMHS, but differences in relevant parameters such as torso angle and resultant acceleration at different locations were found between the dummy and the PMHS. The ATD’s stiffer thoracic spine is hypothesized as a major cause of these differences. PMID:20184847

  19. A comparison between a child-size PMHS and the Hybrid III 6 YO in a sled frontal impact.

    PubMed

    Lopez-Valdes, Francisco J; Forman, Jason; Kent, Richard; Bostrom, Ola; Segui-Gomez, Maria

    2009-10-01

    As pediatric PMHS data are extremely limited, evidence of kinematic differences between pediatric ATDs and live humans comes from comparison of laboratory data to field crash data. Despite the existence of regulations intended to prevent head injuries, these remain the most common serious injuries sustained by children in crashes. In this study, nine frontal sled tests using a Hybrid III 6YO and three tests performed with a child-size adult PMHS were compared, with focus on the kinematic responses (especially of the head) and the seatbelt forces generated during the impact. Two different restraint systems (a pretensioning, force-limiting seatbelt, and a non pretensioning force-limiting standard belt) and two different impact speeds (29 km/h and 48 km/h) were compared. Data from the PMHS were scaled using the erect sitting height of a 50th percentile 6YO and both scaled and unscaled data are presented. The ATD predicted correctly the peak values of the scaled displacements of the PMHS, but differences in relevant parameters such as torso angle and resultant acceleration at different locations were found between the dummy and the PMHS. The ATD's stiffer thoracic spine is hypothesized as a major cause of these differences. PMID:20184847

  20. Comparison of AIS 1990 update 98 versus AIS 2005 for describing PMHS injuries in lateral and oblique sled tests

    PubMed Central

    Yoganandan, Narayan; Pintar, Frank A.; Humm, John R.; Stadter, Gregory W.; Curry, William H.; Brasel, Karen J.

    2013-01-01

    This study analyzed skeletal and organ injuries in pure lateral and oblique impacts from 20 intact post mortem human surrogate (PMHS) sled tests at 6.7 m/s. Injuries to the shoulder, thorax, abdomen, pelvis and spine were scored using AIS 1990–1998 update and 2005. The Injury Severity Scores (ISS) were extracted for both loadings from both versions. Mean age, stature, total body mass and body mass index for pure lateral and oblique tests: 58 and 55 years, 1.7 and 1.8 m, 69 and 66 kg, and 24 and 21 kg/m2. Skeletal injuries (ribs, sternum) occurred in both impacts. However, oblique impacts resulted in more injuries. Pure lateral and oblique impacts ISS: 0 to 16 and 0 to 24, representing a greater potential for injury-related consequences in real-world situations in oblique impacts. Internal organs were more involved in oblique impacts. ISS decreased in AIS 2005, reflecting changes to scoring and drawing attention to potential effects for pre-hospital care/medical aspects. Mean AIS scores for the two load vectors and two AIS coding schemes are included. From automotive crashworthiness perspectives, decreases in injury severities might alter injury risk functions with a shift to lower metrics for the same risk level than current risk estimations. This finding influences dummy-based injury criteria and occupant safety as risk functions are used for countermeasure effectiveness and cost-benefit analyses by regulatory bodies. Increase in organ injuries in oblique loading indicate the importance of this vector as current dummies and injury criteria used in regulations are based on pure lateral impact data. PMID:24406958

  1. Comparison of AIS 1990 update 98 versus AIS 2005 for describing PMHS injuries in lateral and oblique sled tests.

    PubMed

    Yoganandan, Narayan; Pintar, Frank A; Humm, John R; Stadter, Gregory W; Curry, William H; Brasel, Karen J

    2013-01-01

    This study analyzed skeletal and organ injuries in pure lateral and oblique impacts from 20 intact post mortem human surrogate (PMHS) sled tests at 6.7 m/s. Injuries to the shoulder, thorax, abdomen, pelvis and spine were scored using AIS 1990-1998 update and 2005. The Injury Severity Scores (ISS) were extracted for both loadings from both versions. Mean age, stature, total body mass and body mass index for pure lateral and oblique tests: 58 and 55 years, 1.7 and 1.8 m, 69 and 66 kg, and 24 and 21 kg/m(2). Skeletal injuries (ribs, sternum) occurred in both impacts. However, oblique impacts resulted in more injuries. Pure lateral and oblique impacts ISS: 0 to 16 and 0 to 24, representing a greater potential for injury-related consequences in real-world situations in oblique impacts. Internal organs were more involved in oblique impacts. ISS decreased in AIS 2005, reflecting changes to scoring and drawing attention to potential effects for pre-hospital care/medical aspects. Mean AIS scores for the two load vectors and two AIS coding schemes are included. From automotive crashworthiness perspectives, decreases in injury severities might alter injury risk functions with a shift to lower metrics for the same risk level than current risk estimations. This finding influences dummy-based injury criteria and occupant safety as risk functions are used for countermeasure effectiveness and cost-benefit analyses by regulatory bodies. Increase in organ injuries in oblique loading indicate the importance of this vector as current dummies and injury criteria used in regulations are based on pure lateral impact data. PMID:24406958

  2. Effects of Sled Towing on Peak Force, the Rate of Force Development and Sprint Performance During the Acceleration Phase

    PubMed Central

    Martínez-Valencia, María Asunción; Romero-Arenas, Salvador; Elvira, José L.L.; González-Ravé, José María; Navarro-Valdivielso, Fernando; Alcaraz, Pedro E.

    2015-01-01

    Resisted sprint training is believed to increase strength specific to sprinting. Therefore, the knowledge of force output in these tasks is essential. The aim of this study was to analyze the effect of sled towing (10%, 15% and 20% of body mass (Bm)) on sprint performance and force production during the acceleration phase. Twenty-three young experienced sprinters (17 men and 6 women; men = 17.9 ± 3.3 years, 1.79 ± 0.06 m and 69.4 ± 6.1 kg; women = 17.2 ± 1.7 years, 1.65 ± 0.04 m and 56.6 ± 2.3 kg) performed four 30 m sprints from a crouch start. Sprint times in 20 and 30 m sprint, peak force (Fpeak), a peak rate of force development (RFDpeak) and time to RFD (TRFD) in first step were recorded. Repeated-measures ANOVA showed significant increases (p ≤ 0.001) in sprint times (20 and 30 m sprint) for each resisted condition as compared to the unloaded condition. The RFDpeak increased significantly when a load increased (3129.4 ± 894.6 N·s−1, p ≤ 0.05 and 3892.4 ± 1377.9 N·s−1, p ≤ 0.01). Otherwise, no significant increases were found in Fpeak and TRFD. The RFD determines the force that can be generated in the early phase of muscle contraction, and it has been considered a factor that influences performance of force-velocity tasks. The use of a load up to 20% Bm might provide a training stimulus in young sprinters to improve the RFDpeak during the sprint start, and thus, early acceleration. PMID:26240657

  3. Effects of Sled Towing on Peak Force, the Rate of Force Development and Sprint Performance During the Acceleration Phase.

    PubMed

    Martínez-Valencia, María Asunción; Romero-Arenas, Salvador; Elvira, José L L; González-Ravé, José María; Navarro-Valdivielso, Fernando; Alcaraz, Pedro E

    2015-06-27

    Resisted sprint training is believed to increase strength specific to sprinting. Therefore, the knowledge of force output in these tasks is essential. The aim of this study was to analyze the effect of sled towing (10%, 15% and 20% of body mass (Bm)) on sprint performance and force production during the acceleration phase. Twenty-three young experienced sprinters (17 men and 6 women; men = 17.9 ± 3.3 years, 1.79 ± 0.06 m and 69.4 ± 6.1 kg; women = 17.2 ± 1.7 years, 1.65 ± 0.04 m and 56.6 ± 2.3 kg) performed four 30 m sprints from a crouch start. Sprint times in 20 and 30 m sprint, peak force (Fpeak), a peak rate of force development (RFDpeak) and time to RFD (TRFD) in first step were recorded. Repeated-measures ANOVA showed significant increases (p ≤ 0.001) in sprint times (20 and 30 m sprint) for each resisted condition as compared to the unloaded condition. The RFDpeak increased significantly when a load increased (3129.4 ± 894.6 N·s-1, p ≤ 0.05 and 3892.4 ± 1377.9 N·s-1, p ≤ 0.01). Otherwise, no significant increases were found in Fpeak and TRFD. The RFD determines the force that can be generated in the early phase of muscle contraction, and it has been considered a factor that influences performance of force-velocity tasks. The use of a load up to 20% Bm might provide a training stimulus in young sprinters to improve the RFDpeak during the sprint start, and thus, early acceleration. PMID:26240657

  4. Transpulmonary thermodilution (TPTD) before, during and after Sustained Low Efficiency Dialysis (SLED). A Prospective Study on Feasibility of TPTD and Prediction of Successful Fluid Removal

    PubMed Central

    Huber, Wolfgang; Fuchs, Stephan; Minning, Andreas; Küchle, Claudius; Braun, Marlena; Beitz, Analena; Schultheiss, Caroline; Mair, Sebastian; Phillip, Veit; Schmid, Sebastian; Schmid, Roland M.; Lahmer, Tobias

    2016-01-01

    Background Acute kidney injury (AKI) is common in critically ill patients. AKI requires renal replacement therapy (RRT) in up to 10% of patients. Particularly during connection and fluid removal, RRT frequently impairs haemodyamics which impedes recovery from AKI. Therefore, “acute” connection with prefilled tubing and prolonged periods of RRT including sustained low efficiency dialysis (SLED) has been suggested. Furthermore, advanced haemodynamic monitoring using trans-pulmonary thermodilution (TPTD) and pulse contour analysis (PCA) might help to define appropriate fluid removal goals. Objectives, Methods Since data on TPTD to guide RRT are scarce, we investigated the capabilities of TPTD- and PCA-derived parameters to predict feasibility of fluid removal in 51 SLED-sessions (Genius; Fresenius, Germany; blood-flow 150mL/min) in 32 patients with PiCCO-monitoring (Pulsion Medical Systems, Germany). Furthermore, we sought to validate the reliability of TPTD during RRT and investigated the impact of “acute” connection and of disconnection with re-transfusion on haemodynamics. TPTDs were performed immediately before and after connection as well as disconnection. Results Comparison of cardiac index derived from TPTD (CItd) and PCA (CIpc) before, during and after RRT did not give hints for confounding of TPTD by ongoing RRT. Connection to RRT did not result in relevant changes in haemodynamic parameters including CItd. However, disconnection with re-transfusion of the tubing volume resulted in significant increases in CItd, CIpc, CVP, global end-diastolic volume index GEDVI and cardiac power index CPI. Feasibility of the pre-defined ultrafiltration goal without increasing catecholamines by >10% (primary endpoint) was significantly predicted by baseline CPI (ROC-AUC 0.712; p = 0.010) and CItd (ROC-AUC 0.662; p = 0.049). Conclusions TPTD is feasible during SLED. “Acute” connection does not substantially impair haemodynamics. Disconnection with re

  5. Investigation on occupant ejection in high severity rear impact based on post mortem human subject sled tests.

    PubMed

    Petit, Philippe; Luet, Carole; Potier, Pascal; Vallancien, Guy

    2011-11-01

    Occupant protection in rear impact involves two competing challenges. On one hand, allowing a deformation of the seat would act as an energy absorber in low severity impacts and would consequently decrease the risk of neck injuries. However, on the other hand, large deformations of the seat may increase the likelihood of occupant ejection in high severity cases. Green et al. 1987 analyzed a total of 919 accidents in Great Britain. They found that occupant ejection resulted in a risk of severe injuries and fatalities between 3.6 and 4.5 times higher than those cases where no ejection was observed. The sample included single front, side and rear impacts as well as multiple impacts and rollover. The rate of belt use in the sample was 50%. While this analysis included all forms of impact scenarios, nevertheless, it highlights the relative injury severity of occupant ejection. Extensive literature search has found no full-scale rear impact tests involving Post Mortem Human Subjects (PMHS) conducted in a laboratory environment and resulting in ejection. This paper describes a total of 10 sled tests conducted on 3 belted PMHS using a simplified seat design composed of rigid plates assembled such that the angular and linear stiffness of the seatback (including the foam) was modeled. The initial angular position and the range of motion of the seatback, the size of the PMHS, the slack length of the seatbelt, the angular stiffness of the seatback, and the use of headrest were varied in the test matrix while the pulse was kept constant (triangular acceleration with a peak of 17 G at 30 ms and a duration of 95 ms). In the test series, the tests were not run randomly but the likelihood of occupant ejection was increased systematically until ejection occurred. PMHS seat ejection was observed only for the 95th percentile, initially positioned with a seatback angle relative to the vertical equal to 22°, a range of seatback angular motion equal to 44° and no headrest. Repeating

  6. Evaluating the effect of ambient particulate pollution on DNA methylation in Alaskan sled dogs: Potential applications for a sentinel model of human health

    PubMed Central

    Montrose, Luke; Noonan, Curtis; Cho, Yoon Hee; Lee, Joongwon; Harley, John; O’Hara, Todd; Cahill, Catherine; Ward, Tony

    2015-01-01

    Background Exposure to ambient particulate matter (PM) is known to be associated with increased morbidity and mortality in human populations. During the winter months in Fairbanks, Alaska, severe temperature inversions lead to elevated concentrations of ambient PM smaller than 2.5 microns (PM2.5). Sled dogs represent an easily accessible environmentally exposed population that may yield findings informative for human health risk assessment. Objectives In this pilot study, we evaluated whether ambient PM was associated with markers of global methylation in sled dogs. Methods Kennels were strategically recruited to provide a wide PM2.5 exposure gradient for the Fairbanks area. Continuous monitoring of ambient PM2.5 was conducted at each kennel during the winter of 2012/13 using a DustTrak 8530. Dogs received a physical examination and assessment of standard hematology and clinical chemistries. Global methylation was determined using the LUminometric Methylation Assay (LUMA) and 5-Methycytosine (5-mC) Quantification. Results Three sled dog kennels (n ~30 dogs/kennel) were evaluated and sampled. The average PM2.5 concentrations measured for kennels A, B, and C were 90 μg/m3, 48 μg/m3, 16 μg/m3 (p< 0.0001), respectively. The average (standard deviation) global methylation percentage for each kennel measured by LUMA was 76.22 (1.85), 76.52 (1.82), and 76.72 (2.26), respectively. The average (standard deviation) global methylation percentage for each kennel measured by 5-mC was 0.16 (0.04), 0.15 (0.04), and 0.15 (0.05), respectively. There was no statistically significant difference between the three kennels and their average global methylation percentage either by LUMA or 5-mC. Conclusions In this study we evaluated global methylation using LUMA and 5-mC and found no differences between kennels, though exposure to ambient PM2.5 was significantly different between kennels. As more information becomes available regarding immunologically-related canine genes and

  7. Interplanetary variability in particle fluxes recorded by the low energy charged particle detector SLED (about 30 keV to greater than 30 MeV) during the Cruise Phase of the PHOBOS Mission to Mars and its moons

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, S. M. P.; Afonin, V. V.; Gringauz, K. I.; Keppler, E.; Kirsch, E.; Richter, A. K.; Witte, M.; O'Sullivan, D.; Thompson, A.; Kecskemety, K.

    1991-05-01

    Two lightweight telescope detector systems, codenamed SLED-1 and SLED-2, with the capability to monitor electron and ion fluxes within an energy range spanning 34 keV to a few tens of MeV, were launched on the twin spacecraft of the Soviet Phobos Mission to Mars and its moons in July 1988. Solar-related particle enhancements recorded during the Cruise Phase, and also in the near Martian environment, over the interval 19 July 1988-27 March 1989 while the interplanetary medium was in course of changing over from solar-minimum to solar-maximum dominated conditions, are presented. In particular, examples of signatures characterizing events associated with each of these phenomenological states are provided in the context of attempting to elucidate how the solar interplanetary medium evolves from one condition to the other.

  8. Pilot evaluation of physical and psychological effects of a physical trek programme including a dog sledding expedition in children and teenagers with cancer

    PubMed Central

    Vallet, Clothilde; André, Nicolas; Gentet, Jean-Claude; Verschuur, Arnauld; Michel, Gérard; Sotteau, Frédéric; Martha, Cécile; Grélot, Laurent

    2015-01-01

    Aim of the study To evaluate the feasibility and to measure the effects of a six-week-long adapted physical activity programme (APAP), including 5 days of intense dog sledding, on the physical and psychological health of children and adolescents treated for cancer. Methods Eleven children and teenagers (4 girls, 7 boys; mean age 14.3 ± 2.9 years) participated in this monocentric pilot programme of adapted physical activities from February 2013 to March 2013. Seven were still on treatment. The programme lasted 6 weeks. A series of physical tests and psychological questionnaires were carried out before and after the programme. Results All children and teenagers completed the full programme. An improvement in all physical and psychological parameters was observed. Statistically significant differences were observed for global self-esteem (6.2 ± 2.1 to 7.7 ± 1.8; p = 0.02), perceived sport competence (5.3 ± 3.2 to 7.4 ± 2; p = 0.02) and perceived physical strength (5.6 ± 2.5 to 7.1 ± 1.8; p = 0.001). Regarding physical tests, the physical training led to statistically significant improvement for sit-ups (13.8 ± 2.6 to 21.75 ± 5.4; p = 0.01), muscle tone (76 ± 23.7 to 100 ± 22.9; p = 0.01), and resting heart rate (96.1 ± 3.2 to 91.6 ± 4.5; p = 0.03). Conclusion This programme is feasible in children and adolescents even during their oncologic treatment. During the 6-week programme, children and adolescents improved their physical and psychological health, and the putative benefits of the APAP are discussed. A larger randomised trial started in 2014. PMID:26284122

  9. Kinetic and kinematic responses of post mortem human surrogates and the Hybrid III ATD in high-speed frontal sled tests.

    PubMed

    Beeman, Stephanie M; Kemper, Andrew R; Madigan, Michael L; Duma, Stefan M

    2013-06-01

    Despite improvements in vehicle design and safety technologies, frontal automotive collisions continue to result in a substantial number of injuries and fatalities each year. Although a considerable amount of research has been performed on PMHSs and ATDs, matched dynamic whole-body frontal testing with PMHSs and the current ATD aimed at quantifying both kinetic and kinematic data in a single controlled study is lacking in the literature. Therefore, a total of 4 dynamic matched frontal sled tests were performed with three male PMHSs and a Hybrid III 50th percentile male ATD (28.6g, Δv=40 kph). Each subject was restrained using a 4 kN load limiting, driver-side, 3-point seatbelt. Belt force was measured for the lap belt and shoulder belt. Reaction forces were measured at the seat pan, seat back, independent foot plates, and steering column. Linear head acceleration, angular head acceleration, and pelvic acceleration were measured for all subjects. Acceleration of C7, T7, T12, both femurs, and both tibias were also measured for the PMHSs. A Vicon motion analysis system, consisting of 12 MX-T20 2 megapixel cameras, was used to quantify subject 3D motion (±1 mm) at a rate of 1 kHz. Excursions of select anatomical regions were normalized to their respective initial positions and compared by test condition and between subject types. Notable discrepancies were observed in the responses of the PMHSs and the ATD. The reaction forces and belt loading for the ATD, particularly foot plate, seat back, steering column, and lap belt forces, were not in agreement with those of the PMHSs. The forward excursions of the ATD were consistently within those of the PMHSs with the exception of the left upper extremity. This could potentially be due to the known limitations of the Hybrid III ATD shoulder and chest. The results presented herein demonstrate that there are some limitations to the current Hybrid III ATD under the loading conditions evaluated in the current study. Overall

  10. An inflatable belt system in the rear seat occupant environment: investigating feasibility and benefit in frontal impact sled tests with a 50th percentile male ATD

    PubMed Central

    Forman, Jason L.; Lopez-Valdes, Francisco J.; Dennis, Nate; Kent, Richard W.; Tanji, Hiromasa; Higuchi, Kazuo

    2010-01-01

    Frontal-impact airbag systems have the potential to provide a benefit to rear seat occupants by distributing restraining forces over the body in a manner not possible using belts alone. This study sought to investigate the effects of incorporating a belt-integrated airbag (“airbelt”) into a rear seat occupant restraint system. Frontal impact sled tests were performed with a Hybrid III 50th percentile male anthropomorphic test device (ATD) seated in the right-rear passenger position of a 2004 mid-sized sedan buck. Tests were performed at 48 km/h (20 g, 100 ms acceleration pulse) and 29 km/h (11 g, 100 ms). The restraints consisted of a 3-point belt system with a cylindrical airbag integrated into the upper portion of the shoulder belt. The airbag was tapered in shape, with a maximum diameter of 16 cm (at the shoulder) that decreased to 4 cm at the mid-chest. A 2.5 kN force-limiter was integrated into the shoulder-belt retractor, and a 2.3 kN pretensioner was present in the out-board anchor of the lap belt. Six ATD tests (three 48 km/h and three 29 km/h) were performed with the airbelt system. These were compared to previous frontal-impact, rear seat ATD tests with a standard (not-force-limited, not-pretensioned) 3-point belt system and a progressive force-limiting (peak 4.4 kN), pretensioning (FL+PT) 3-point belt system. In the 48 km/h tests, the airbelt resulted in significantly less (p<0.05, two-tailed Student’s t-test) posterior displacement of the sternum towards the spine (chest deflection) than both the standard and FL+PT belt systems (airbelt: average 13±1.1 mm standard deviation; standard belt: 33±2.3 mm; FL+PT belt: 23±2.6 mm). This was consistent with a significant reduction in the peak upper shoulder belt force (airbelt: 2.7±0.1 kN; standard belt: 8.7±0.3 kN; FL+PT belt: 4.4±0.1 kN), and was accompanied by a small increase in forward motion of the head (airbelt: 54±0.4 cm; standard belt: 45±1.3 cm; FL+PT belt: 47±1.1 cm) The airbelt system

  11. Portable Linear Sled (PLS) for biomedical research

    NASA Technical Reports Server (NTRS)

    Vallotton, Will; Matsuhiro, Dennis; Wynn, Tom; Temple, John

    1993-01-01

    The PLS is a portable linear motion generating device conceived by researchers at Ames Research Center's Vestibular Research Facility and designed by engineers at Ames for the study of motion sickness in space. It is an extremely smooth apparatus, powered by linear motors and suspended on air bearings which ride on precision ground ceramic ways.

  12. Operations and maintenance manual for the linear accelerator (sled)

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The Linear Accelerator, a sliding chair which is pulled along a stationary platform in a horizontal axis is described. The driving force is a motor controlled by a velocity loop amplifier, and the mechanical link to the chair is a steel cable. The chair is moved in forward and reverse directions as indicated by the direction of motor rotation. The system operation is described with emphasis on the electronic control and monitoring functions. Line-by-line schematics and wire lists are included.

  13. Tradition and Technology: Sea Ice Science on Inuit Sleds

    NASA Astrophysics Data System (ADS)

    Wilkinson, Jeremy P.; Hanson, Susanne; Hughes, Nick E.; James, Alistair; Jones, Bryn; MacKinnon, Rory; Rysgaard, Søren; Toudal, Leif

    2011-01-01

    The Arctic is home to a circumpolar community of native people whose culture and traditions have enabled them to thrive in what most would perceive as a totally inhospitable and untenable environment. In many ways, sea ice can be viewed as the glue that binds these northern communities together; it is utilized in all aspects of their daily life. Sea ice acts as highways of the north; indeed, one can travel on these highways with dogsleds and snowmobiles. These travels over the frozen ocean occur at all periods of the sea ice cycle and over different ice types and ages. Excursions may be hunting trips to remote regions or social visits to nearby villages. Furthermore, hunting on the sea ice contributes to the health, culture, and commercial income of a community.

  14. Sled Dogs, Musher Math, and More: Theme Teaching and the Alaskan Iditarod.

    ERIC Educational Resources Information Center

    Park-Seldomridge, Anne

    1995-01-01

    A teacher of upper elementary deaf students describes a multidisciplinary study unit focused on the Alaskan dogsled race, the Iditarod. Activities included studying Alaskan geography and history, following specific racers (mushers) through daily updates faxed from Alaska, writing letters to mushers, calculating math facts related to the race,…

  15. An experimental meat-free diet maintained haematological characteristics in sprint-racing sled dogs.

    PubMed

    Brown, Wendy Y; Vanselow, Barbara A; Redman, Andrew J; Pluske, John R

    2009-11-01

    A dog's nutrient requirements can theoretically be met from a properly balanced meat-free diet; however, proof for this is lacking. Exercise places additional demands on the body, and dogs fed a meat-free diet may be at increased risk of developing sports anaemia. We hypothesised that exercising dogs would remain in good health and not develop anaemia when fed a nutritionally balanced meat-free diet. To this end, twelve sprint-racing Siberian huskies were fed either a commercial diet recommended for active dogs (n 6), or a meat-free diet formulated to the same nutrient specifications (n 6). The commercial diet contained 43 % poultry meal, whereas soyabean meal and maize gluten made up 43 % of the meat-free diet, as the main protein ingredients. Dogs were fed these diets as their sole nutrient intake for 16 weeks, including 10 weeks of competitive racing. Blood samples were collected at weeks 0, 3, 8 and 16, and veterinary health checks were conducted at weeks 0, 8 and 16. Haematology results for all dogs, irrespective of diet, were within normal range throughout the study and the consulting veterinarian assessed all dogs to be in excellent physical condition. No dogs in the present study developed anaemia. On the contrary, erythrocyte counts and Hb values increased significantly over time (P < 0.01) in both groups of dogs. The present study is the first to demonstrate that a carefully balanced meat-free diet can maintain normal haematological values in exercising dogs. PMID:19480731

  16. "Heavy Sledding": Barriers to Community Participation in Beaufort Sea Hydrocarbon Developments.

    ERIC Educational Resources Information Center

    Durst, Douglas

    1994-01-01

    This description of the Canadian government's assessment of the social impact of hydrocarbon exploration in the Arctic demonstrates barriers to citizen involvement: ad hoc nature, travel and child care problems, and lack of enough volunteers. Recommendations for community participation in impact assessment are given. (SK)

  17. Molecular Sleds and More: Novel Antiviral Agents via Single-Molecule Biology (441st Brookhaven Lecture)

    SciTech Connect

    Mangel, Wally

    2008-10-15

    Vaccines are effective against viruses such as polio and measles, but vaccines against other important viruses, such as HIV and flu viruses, may be impossible to obtain. These viruses change their genetic makeup each time they replicate so that the immune system cannot recognize all their variations. Hence it is important to develop new antiviral agents that inhibit virus replication. During this lecture, Dr. Mangel will discuss his group's work with a model system, the human adenovirus, which causes, among other ailments, pink eye, blindness and obesity. Mangel's team has developed a promising drug candidate that works by inihibiting adenovirus proteinase, an enzyme necessary for viral replication.

  18. Evaluation of steering control devices in adapted cars using sled deceleration tests

    NASA Astrophysics Data System (ADS)

    Eixerés, B.; Masiá, J.; Dols, J. F.; Esquerdo, T. V.

    2009-11-01

    Steering control devices used by disabled drivers can reduce passive safety, interfering with the existing systems of safety in the vehicle or causing injury to the occupants [1]. In this article, the results obtained in different dynamic tests carried out in a crash test simulator are presented. These tests were carried out on the steering devices which interfere the most with the deployment of the driver's airbag and also with the knee airbag in a Citroen C5.

  19. Dog Sleds to Satellites: Library Service in the Land of the Midnight Sun.

    ERIC Educational Resources Information Center

    Herie, Euclid J.

    The role of the Canadian National Institute for the Blind (CNIB) in serving the aboriginal (indigenous) peoples of Canada, especially those in the Northwest Territories (NWT), is described, and the possibilities for future library delivery systems are discussed. The right of these peoples, and of all blind and visually impaired persons, to…

  20. Mid-J CO Shock Tracing Observations of Infrared Dark Clouds. III. SLED Fitting

    NASA Astrophysics Data System (ADS)

    Pon, A.; Kaufman, M. J.; Johnstone, D.; Caselli, P.; Fontani, F.; Butler, M. J.; Jiménez-Serra, I.; Palau, A.; Tan, J. C.

    2016-08-01

    Giant molecular clouds contain supersonic turbulence that can locally heat small fractions of gas to over 100 K. We run shock models for low-velocity, C-type shocks propagating into gas with densities between 103 and 105 cm‑3 and find that CO lines are the most important cooling lines. Comparison to photodissociation region (PDR) models indicates that mid-J CO lines (J = 8 \\to 7 and higher) should be dominated by emission from shocked gas. In Papers I and II we presented CO J = 3 \\to 2, 8 \\to 7, and 9 \\to 8 observations toward four primarily quiescent clumps within infrared dark clouds. Here we fit PDR models to the combined spectral line energy distributions and show that the PDR models that best fit the low-J CO emission underpredict the mid-J CO emission by orders of magnitude, strongly hinting at a hot gas component within these clumps. The low-J CO data clearly show that the integrated intensities of both the CO J = 8 \\to 7 and 9 \\to 8 lines are anomalously high, such that the line ratio can be used to characterize the hot gas component. Shock models are reasonably consistent with the observed mid-J CO emission, with models with densities near {10}4.5 cm‑3 providing the best agreement. Where this mid-J CO is detected, the mean volume filling factor of the hot gas is 0.1%. Much of the observed mid-J CO emission, however, is also associated with known protostars and may be due to protostellar feedback.

  1. The AMT maglev test sled -- EML weapons technology transition to transportation

    SciTech Connect

    Schaaf, J.C. Jr.; Zowarka, R.C. Jr.; Davey, K.; Weldon, J.M.

    1997-01-01

    Technology spinoffs from prior electromagnetic launcher work enhance a magnetic levitation transportation system test bed being developed by American Maglev Technology of Florida. This project uses a series wound linear DC motor and brushes to simplify the magnetic levitation propulsion system. It takes advantage of previous related work in electromagnetic launcher technology to achieve success with this innovative design. Technology and knowledge gained from developments for homopolar generators and proposed railgun arc control are key to successful performance. This contribution supports a cost effective design that is competitive with alternative concepts. Brushes transfer power from the guideway (rail) to the vehicle (armature) in a novel design that activates the guideway only under the vehicle, reducing power losses and guideway construction costs. The vehicle carries no power for propulsion and levitation, and acts only as a conduit for the power through the high speed brushes. Brush selection and performance is based on previous EML homopolar generator research. A counterpulse circuit, first introduced in an early EML conference, is used to suppress arcing on the trailing brush and to transfer inductive energy to the next propulsion coil. Isolated static lift and preliminary propulsion tests have been completed, and integrated propulsion and lift tests are scheduled in early 1996.

  2. Haemorrhagic pneumonia in sled dogs caused by Streptococcus equi subsp. zooepidemicus - one fatality and two full recoveries: a case report

    PubMed Central

    2013-01-01

    In spite of yearly vaccination, outbreaks of canine infectious respiratory disease are periodically seen amongst domestic dogs. These infections compromise host defense mechanisms, and, when combined with other stressful events, allow opportunistic pathogens like Streptococcus equi subsp. zooepidemicus to create serious disease. Early recognition and treatment are tremendously important for a successful outcome in these cases. A polyvalent vaccine was given to 22 racing dogs three days after a competition, followed by two days of rest, and then the dogs were returned to regular training. Coughing was noticed among the dogs four days after immunisation. Three days after this outbreak one of the dogs was unusually silent and was found dead the next morning. Simultaneously two other dogs developed haemorrhagic expectorate, depression and dyspnea and were brought in to the veterinary hospital. Streptococcus equi subsp. zooepidemicus was isolated in pure culture from all three cases. They were treated and rehabilitated successfully, and won a sledge race three months later. This paper discusses the necropsy results, treatment regime, rehabilitation and the chronology of vaccination, stressful events and disease. PMID:24020788

  3. Evaluation of Sled Tests for Spacecraft Dynamic Environments using the Small Female and Large Male Hybrid III Anthropomorphic Test Devices

    NASA Technical Reports Server (NTRS)

    Wells, Jessica A.; Somers, Jeffrey T.; Newby, Nathaniel J.; Putnam, Jacob F.; Currie-Gregg, Nancy J.; Lawrence, Charles

    2016-01-01

    Anthropomorphic test devices (ATD) are widely used for military and automotive applications. These ATDs have been correlated to certain types of human injuries largely involving automotive-type energetics and directions of impact. Spacecraft dynamic events involve very different impact characteristics and, in the case of landings, require lower levels of acceptable injury risk due to the certainty of impact occurrence. This test series evaluated the small female and large male Hybrid IIII ATDs for spacecraft dynamic events.

  4. Signatures of the Martian moon PHOBOS in the fluxes of energetic particles as measured by experiment SLED onboard PHOBOS 2

    NASA Astrophysics Data System (ADS)

    Kirsch, E.; McKenna-Lawlor, S. M. P.; Afonin, V. V.; Keppler, E.; Livi, S.; Rosenbauer, H.; Witte, M.; Schwingenschuh, K.; Thompson, A.; O'Sullivan, D.

    1993-06-01

    Energetic particles Ep greater than 34 keV, E0+ greater than 55 keV), plasma ions (30 eV-6 keV) and magnetic fields have been observed onboard Phobos 2 during the approach phases of the spacecraft to the Phobos moon in February/March 1989. Water ions and protons escaping as neutral water molecules from Phobos and the Martian tail can generally be accelerated by the pickup process. The present study is concerned with the acceleration of particles at the evening side (alpha s/c = 90 deg) of the Martian bowshock, which escaped as neutrals, especially from the tail or at the front side of Phobos. Since the interplanetary magnetic field forms quasiperpendicular and quasiparallel shocks with the Martian bowshock, the shock drift and the Fermi acceleration process were considered as processes for a further acceleration. The observed particle fluxes are interpreted as protons of 34-200 keV and O(+) ions of 55-225 keV energy.

  5. 2. BUILDING 0521, SOUTH REAR AND EAST SIDE. Looking to ...

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

    2. BUILDING 0521, SOUTH REAR AND EAST SIDE. Looking to northwest from access road. - Edwards Air Force Base, South Base Sled Track, Earth Covered Bunker Types, North of Sled Track, Lancaster, Los Angeles County, CA

  6. 5. BUILDING 0503, INTERIOR WOODEN ARCHES. Looking south from entrance. ...

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

    5. BUILDING 0503, INTERIOR WOODEN ARCHES. Looking south from entrance. - Edwards Air Force Base, South Base Sled Track, Earth Covered Bunker Types, North of Sled Track, Lancaster, Los Angeles County, CA

  7. 3. BUILDING 0503, NORTH FRONT AND WEST SIDE, WITH LOADING ...

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

    3. BUILDING 0503, NORTH FRONT AND WEST SIDE, WITH LOADING DOCK AND GABLE ROOFED SHED. - Edwards Air Force Base, South Base Sled Track, Earth Covered Bunker Types, North of Sled Track, Lancaster, Los Angeles County, CA

  8. NORTH SIDE FACING TRACK, SHOWING ELECTRICAL BOX AND CONCRETE VAULT ...

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

    NORTH SIDE FACING TRACK, SHOWING ELECTRICAL BOX AND CONCRETE VAULT - Edwards Air Force Base, South Base Sled Track, Electrical Distribution Station, South side of Sled Track, Lancaster, Los Angeles County, CA

  9. Low-Density Supersonic Decelerator Test

    NASA Video Gallery

    NASA recently performed a trial run on a rocket sled test fixture, powered by rockets, to replicate the forces a supersonic spacecraft would experience prior to landing. The sled tests will allow t...

  10. 5. NORTH SIDE AND WEST REAR. Edwards Air Force ...

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

    5. NORTH SIDE AND WEST REAR. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  11. 6. OUTER BLAST DOOR, WEST REAR. Edwards Air Force ...

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

    6. OUTER BLAST DOOR, WEST REAR. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  12. 3. SOUTH SIDE. Edwards Air Force Base, South Base ...

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

    3. SOUTH SIDE. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  13. 10. ENTRY STAIRWELL TO CABLE TUNNEL, ABOUT THREE QUARTERS THE ...

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

    10. ENTRY STAIRWELL TO CABLE TUNNEL, ABOUT THREE QUARTERS THE DISTANCE TO THE SLED LAUNCHING PAD FROM THE FIRING CONTROL BLOCKHOUSE 0545. Looking west northwest. - Edwards Air Force Base, South Base Sled Track, Firing Control Blockhouse, South of Sled Track at east end, Lancaster, Los Angeles County, CA

  14. A Front-Row Seat at a Wheelchair Crash Test: EP Kicks Off Its Wheelchair Transportation Safety Series with a Visit to the University of Michigan's Transportation Research Institute

    ERIC Educational Resources Information Center

    Hollingsworth, Jan Carter

    2007-01-01

    The centerpiece of the University of Michigan's Transportation Research Institute (UMTRI) Sled Lab is "the impact sled," as it is called in the business. It's the business of conducting sled impact tests, perhaps better known as crash tests, on all types of wheelchairs and wheelchair seating systems as well as wheelchair tiedowns and…

  15. The oral [(13)C]bicarbonate technique for measurement of short-term energy expenditure of sled dogs and their physiological response to diets with different fat:carbohydrate ratios.

    PubMed

    Larsson, Caroline; Ahlstrøm, Øystein; Junghans, Peter; Jensen, Rasmus B; Blache, Dominique; Tauson, Anne-Helene

    2015-01-01

    The oral [(13)C]bicarbonate technique (o(13)CBT) was assessed for the determination of short-term energy expenditure (EE) under field conditions. A total of eight Alaskan huskies were fed two experimental diets in a cross-over experiment including two periods of 3 weeks. Effects of diets on EE, apparent total tract digestibility (ATTD) and on plasma hormones, blood lactate and glucose were furthermore investigated. The percentages of metabolisable energy derived from protein (P), fat (F) and carbohydrates (C) were 26:58:16 in the PFC diet and 24:75:1 in the PF diet. Measurements of EE were performed in the post-absorptive state during rest. Blood samples were collected during rest and exercise and ATTD was determined after days with rest and with exercise. EE was higher (P < 0·01) in period 2 than in period 1 (68 v. 48 kJ/kg body weight(0·75) per h). The ATTD of organic matter, crude protein and crude fat was higher (P < 0·01) in the PF diet compared with the PFC diet, and lower (P < 0·01) for total carbohydrates. Exercise did not affect ATTD. Higher (P < 0·01) insulin-like growth factor 1 and leptin concentrations were measured when fed the PF diet compared with the PFC diet. Concentrations of insulin decreased (P < 0·01), whereas cortisol and ghrelin increased (P < 0·05), after exercise. There was no effect of diet on blood lactate and glucose, but higher (P < 0·001) lactate concentrations were measured in period 1 than in period 2. The results suggest that the o(13)CBT can be used in the field to estimate short-term EE in dogs during resting conditions. Higher ATTD and energy density of the PF diet may be beneficial when energy requirements are high. PMID:26495123

  16. Experiments with very-high-power RF pulses at SLAC

    SciTech Connect

    Hogg, H.A.; Loew, G.A.; Price, V.G.

    1983-03-01

    Experiments in which the powers of two SLAC klystrons were combined and fed into a resonant cavity pulse-compression system (SLED) are described. Pulse powers up to 65 MW into SLED were reached. The corresponding instantaneous peak power out of SLED was 390 MW. After normal initial aging, no persistent RF breakdown problems were encountered. X-radiation at the SLED cavities was generally less than 400 mR/h after aging. The theoretical relationship between x-radiation intensity and RF electric field strength is discussed.

  17. 15. ELEVATED CAMERA STAND, SHOWING LINE OF CAMERA STANDS PARALLEL ...

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

    15. ELEVATED CAMERA STAND, SHOWING LINE OF CAMERA STANDS PARALLEL TO SLED TRACK. Looking west southwest down Camera Road. - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  18. 43 CFR 423.37 - Winter activities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ....37 Winter activities. (a) You must not tow persons on skis, sleds, or other sliding devices with a motor vehicle or snowmobile, except that you may tow sleds designed to be towed behind snowmobiles if joined to the towing snowmobile with a rigid hitching mechanism, and you may tow disabled snowmobiles...

  19. 13. WALKWAY FROM LAUNCHING PAD TO CABLE TUNNEL STAIRWELL, ALSO ...

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

    13. WALKWAY FROM LAUNCHING PAD TO CABLE TUNNEL STAIRWELL, ALSO SHOWING A PROTECTIVE BERM AT TOP LEFT, AND FIRING CONTROL BLOCKHOUSE 0545 AT TOP RIGHT. - Edwards Air Force Base, South Base Sled Track, Firing Control Blockhouse, South of Sled Track at east end, Lancaster, Los Angeles County, CA

  20. NORTH FRONT AND WEST SIDE, HIGH ENCLOSED METAL OBSERVATION TOWER ...

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

    NORTH FRONT AND WEST SIDE, HIGH ENCLOSED METAL OBSERVATION TOWER LOCATED APPROXIMATELY 1800 FEET SOUTH OF TRACK. Looking southeast - Edwards Air Force Base, South Base Sled Track, Observation Tower, South of west end of Sled Track, Lancaster, Los Angeles County, CA

  1. 11. ENTRY STAIRWELL TO CABLE TUNNEL. REMAINS OF ELECTRICAL DISTRIBUTION ...

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

    11. ENTRY STAIRWELL TO CABLE TUNNEL. REMAINS OF ELECTRICAL DISTRIBUTION STATIONS AT LEFT, TRACKSIDE CAMERA STAND AT FAR RIGHT. Looking northeast toward launch pad. - Edwards Air Force Base, South Base Sled Track, Firing Control Blockhouse, South of Sled Track at east end, Lancaster, Los Angeles County, CA

  2. 2. OBLIQUE VIEW OF WEST FRONT. The frames on an ...

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

    2. OBLIQUE VIEW OF WEST FRONT. The frames on an angle originally held mirrors for viewing the tests from inside the building. Vertical frame originally held bullet glass. - Edwards Air Force Base, South Base Sled Track, Firing Control Blockhouse, South of Sled Track at east end, Lancaster, Los Angeles County, CA

  3. 23. "GAFFTC 20 APR 60, H65A F106A; ESCAPE SYSTEM RUN ...

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

    23. "G-AFFTC 20 APR 60, H-6-5A F-106A; ESCAPE SYSTEM RUN 5A." Testing the ejection system on a Convair sled. - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  4. 24. "GAFFTC 29 SEP 60, F106B STATIC TEST 1." Test ...

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

    24. "G-AFFTC 29 SEP 60, F-106B STATIC TEST 1." Test of the Convair sled escape system at static test site east of Station "50". File no. 11,988-60. - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  5. 9. A VIEW ALONG WEST REAR WALL SHOWING CONFIGURATION FOR ...

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

    9. A VIEW ALONG WEST REAR WALL SHOWING CONFIGURATION FOR OBSERVATION MIRRORS. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  6. 7. BULLET GLASS OBSERVATION WINDOW AT GROUND LEVEL ON WEST ...

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

    7. BULLET GLASS OBSERVATION WINDOW AT GROUND LEVEL ON WEST REAR. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  7. 1. OVERVIEW SHOWING FIRING CONTROL BLOCKHOUSE 0502 AND ADJACENT OBSERVATION ...

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

    1. OVERVIEW SHOWING FIRING CONTROL BLOCKHOUSE 0502 AND ADJACENT OBSERVATION TOWER. WATER BRAKE TROUGH SEGMENT AT LOWER RIGHT. Looking north northeast. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  8. 2. WEST REAR, WITH PORTHOLE ESCAPE HATCH ABOVE ENTRY DOOR. ...

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

    2. WEST REAR, WITH PORTHOLE ESCAPE HATCH ABOVE ENTRY DOOR. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  9. 8. INTERIOR, CONTROL AND INSTRUMENTATION ROOM. Looking southwest toward entrance ...

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

    8. INTERIOR, CONTROL AND INSTRUMENTATION ROOM. Looking southwest toward entrance and inner blast door. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  10. 4. EAST FRONT. Original viewing windows on upper level have ...

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

    4. EAST FRONT. Original viewing windows on upper level have been filled in with concrete block. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  11. SOUTHWEST REAR AND SOUTHEAST SIDE. Protective berm at left shields ...

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

    SOUTHWEST REAR AND SOUTHEAST SIDE. Protective berm at left shields Air Supply building from launch pad - Edwards Air Force Base, South Base Sled Track, Air Supply Building for Building No. 0545, South of Sled Track at east end, Lancaster, Los Angeles County, CA

  12. Spacelab Life Sciences-1 electrical diagnostic expert system

    NASA Technical Reports Server (NTRS)

    Kao, C. Y.; Morris, W. S.

    1989-01-01

    The Spacelab Life Sciences-1 (SLS-1) Electrical Diagnostic (SLED) expert system is a continuous, real time knowledge-based system to monitor and diagnose electrical system problems in the Spacelab. After fault isolation, the SLED system provides corrective procedures and advice to the ground-based console operator. The SLED system updates its knowledge about the status of Spacelab every 3 seconds. The system supports multiprocessing of malfunctions and allows multiple failures to be handled simultaneously. Information which is readily available via a mouse click includes: general information about the system and each component, the electrical schematics, the recovery procedures of each malfunction, and an explanation of the diagnosis.

  13. Spacelab Life Sciences-1 electrical diagnostics expert system

    NASA Technical Reports Server (NTRS)

    Kao, Cheng Y.; Morris, William S.

    1989-01-01

    The Spacelab Life Sciences-1 (SLS-1) Electrical Diagnostic (SLED) expert system is a continuous real time knowledge-based system to monitor and diagnose electrical system problems in the Spacelab. After fault isolation, the SLED system provides corrective procedures and advice to the ground-based console operator. The SLED system updates its knowledge about the status of Spacelab every 3 seconds. The system supports multiprocessing of malfunctions and allows multiple failures to be handled simultaneously. Information which is readily available via a mouse click includes: general information about the system and each component, the electrical schematics, the recovery procedures of each malfunction, and an explanation of the diagnosis.

  14. A case for Redundant Arrays of Inexpensive Disks (RAID)

    NASA Technical Reports Server (NTRS)

    Patterson, David A.; Gibson, Garth; Katz, Randy H.

    1988-01-01

    Increasing performance of CPUs and memories will be squandered if not matched by a similar performance increase in I/O. While the capacity of Single Large Expensive Disks (SLED) has grown rapidly, the performance improvement of SLED has been modest. Redundant Arrays of Inexpensive Disks (RAID), based on the magnetic disk technology developed for personal computers, offers an attractive alternative to SLED, promising improvements of an order of magnitude in performance, reliability, power consumption, and scalability. This paper introduces five levels of RAIDs, giving their relative cost/performance, and compares RAID to an IBM 3380 and a Fujitsu Super Eagle.

  15. What's a Scab?

    MedlinePlus

    ... Words En Español What Other Kids Are Reading Movie: Digestive System Winter Sports: Sledding, Skiing, Snowboarding, Skating ... a scab forms. Scabs are usually crusty and dark red or brown. Their job is to protect ...

  16. Learning the "Wright' Way to Fly!

    NASA Video Gallery

    This lesson uses the online NASA CONNECT™™: The "Wright" Math Educator Guide, the NASA Aeronautics Activity Guide and the Sled Kite activity to help students learn how the Wright brothers developed...

  17. Scabies

    MedlinePlus

    ... Sledding, Skiing, Snowboarding, Skating Crushes What's a Booger? Scabies KidsHealth > For Kids > Scabies Print A A A ... Stop to Scabies en español Sarna What Is Scabies? Scabies (say: SKAY-beez) is an itchy skin ...

  18. Diabetes: What's True and False?

    MedlinePlus

    ... Sledding, Skiing, Snowboarding, Skating Crushes What's a Booger? Diabetes: What's True and False? KidsHealth > For Kids > Diabetes: ... True or False: Eating Too Much Sugar Causes Diabetes False: When kids get type 1 diabetes , it's ...

  19. Meal Plans: What Kids with Diabetes Need to Know

    MedlinePlus

    ... Dictionary of Medical Words En Español What Other Kids Are Reading Movie: Digestive System Winter Sports: Sledding, ... Skating Crushes What's a Booger? Meal Plans: What Kids With Diabetes Need to Know KidsHealth > For Kids > ...

  20. 19. MUELLER FIRE HYDRANT NEAR LAUNCHING PAD IN STATION "0". ...

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

    19. MUELLER FIRE HYDRANT NEAR LAUNCHING PAD IN STATION "0". - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  1. 76 FR 77552 - Certain Light-Emitting Diodes and Products Containing Same; Determination Not To Review an...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-13

    ... August 18, 2011, based on a ] complaint filed by SLED. 76 FR 51396-97 (Aug. 18, 2011). A corrected Notice... Investigations will not participate as a party in this investigation. 76 FR 52348-49 (Aug. 22, 2011)....

  2. SOUTHEAST FRONT AND NORTHEAST SIDE. Looking northwest from top of ...

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

    SOUTHEAST FRONT AND NORTHEAST SIDE. Looking northwest from top of protective berm - Edwards Air Force Base, South Base Sled Track, Water Pump Station, Area "O" at east end, northwest of fuel storage, Lancaster, Los Angeles County, CA

  3. Acne Myths

    MedlinePlus

    ... Sledding, Skiing, Snowboarding, Skating Crushes What's a Booger? Acne Myths KidsHealth > For Kids > Acne Myths Print A ... get your acne under control. Myth: Stress causes acne. Fact: Are you worried that the big test ...

  4. Cold-Weather Sports

    MedlinePlus

    ... try sledding . Or, if you prefer ice to snow, think hockey or figure skating. Runners can also ... freeze. Regardless of how you get down a snow-covered slope, always watch for obstacles such as ...

  5. Frostbite

    MedlinePlus

    ... the Cold Like We Do? Cold, Ice, and Snow Safety Cold-Weather Sports and Your Family Safety ... Frostbite How to Be Safe in Ice and Snow Stay Safe Center Winter Sports: Sledding, Skiing, Snowboarding, ...

  6. What's Spit?

    MedlinePlus

    ... Words En Español What Other Kids Are Reading Movie: Digestive System Winter Sports: Sledding, Skiing, Snowboarding, Skating ... For Kids For Parents MORE ON THIS TOPIC Movie: Tongue What Are Taste Buds? Word! Saliva What's ...

  7. Life with Lupus

    MedlinePlus

    ... Words En Español What Other Kids Are Reading Movie: Digestive System Winter Sports: Sledding, Skiing, Snowboarding, Skating ... Parents MORE ON THIS TOPIC Guillain-Barré Syndrome Movie: Immune System What Are Glands? Your Immune System ...

  8. 15. "FIRING CONTROL BLOCKHOUSE; STATION '0' AREA; PLAN, AND SECTIONS." ...

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

    15. "FIRING CONTROL BLOCKHOUSE; STATION '0' AREA; PLAN, AND SECTIONS." Specifications No. ENG-04-353-57-75; Drawing No. AF-60-09-15; sheet 40 of 96; D.O. Series No. AF 1394/60, Rev. A. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 5296 Rev. A, Date: 11/17/59. - Edwards Air Force Base, South Base Sled Track, Firing Control Blockhouse, South of Sled Track at east end, Lancaster, Los Angeles County, CA

  9. 14. "FIRING CONTROL BLOCKHOUSE; STATION '0' AREA; PLAN, ELEVATIONS, SECTION, ...

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

    14. "FIRING CONTROL BLOCKHOUSE; STATION '0' AREA; PLAN, ELEVATIONS, SECTION, DETAIL AND SCHED." Specifications No. ENG-04-353-57-75; Drawing No. AF-60-09-15; sheet 21 of 96; D.O. Series No. AF 1394/39, Rev. A. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 5296 Rev. A, Date: 11/17/59. - Edwards Air Force Base, South Base Sled Track, Firing Control Blockhouse, South of Sled Track at east end, Lancaster, Los Angeles County, CA

  10. 26. "AIR INSTALLATIONS; EDWARDS AIR FORCE BASE, CALIFORNIA; HIGH SPEED ...

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

    26. "AIR INSTALLATIONS; EDWARDS AIR FORCE BASE, CALIFORNIA; HIGH SPEED TEST TRACK." Drawing No. 10-259. One inch to 400 feet plan of original 10,000-foot sled track. No date. No D.O. series number. No headings as above. - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  11. A system for measuring bottom profile, waves and currents in the high-energy nearshore environment

    USGS Publications Warehouse

    Sallenger, A.H., Jr.; Howard, P.C.; Fletcher, C. H., III; Howd, P.A.

    1983-01-01

    A new data-acquisition system capable of measuring waves, currents and the nearshore profile in breaking waves as high as 5 m has been developed and successfully field-tested. Components of the mechanical system are a sled carrying a vertical mast, a double-drum winch placed landward of the beach, and a line that runs from one drum of the winch around three blocks, which are the corners of a right triangle, to the other drum of the winch. The sled is attached to the shore-normal side of the triangular line arrangement and is pulled offshore by one drum of the winch and onshore by the other. The profile is measured as the sled is towed along the shore-normal transect using an infrared rangefinder mounted landward of the winch and optical prisms mounted on top of the sled's mast. A pressure sensor and two-axis electromagnetic current meter are mounted on the frame of the sled. These data are encoded on the sled and telemetered to a receiving/recording station onshore. Preliminary results suggest that near-bottom offshore-flowing currents during periods of high-energy swell are important in forcing changes to the configuration of the nearshore profile. ?? 1983.

  12. Using head-on collisions to compare risk of driver death by frontal air bag generation: a matched-pair cohort study.

    PubMed

    Braver, Elisa R; Kufera, Joseph A; Alexander, Melvin T; Scerbo, Marge; Volpini, Karen; Lloyd, Joseph P

    2008-03-01

    US air bag regulations were changed in 1997 to allow tests of unbelted male dummies in vehicles mounted and accelerated on sleds, resulting in longer crash pulses than rigid-barrier crashes. This change facilitated depowering of frontal air bags and was intended to reduce air bag-induced deaths. Controversy ensued as to whether sled-certified air bags could increase adult fatality risk. A matched-pair cohort study of two-vehicle, head-on, fatal collisions between drivers involving first-generation versus sled-certified air bags during 1998-2005 was conducted by using Fatality Analysis Reporting System data. Sled certification was ascertained from public information and a survey of automakers. Conditional Poisson regression for matched-pair cohorts was used to estimate risk ratios adjusted for age, seat belt status, vehicle type, passenger car size, and model year for driver deaths in vehicles with sled-certified air bags versus first-generation air bags. For all passenger-vehicle pairs, the adjusted risk ratio was 0.87 (95% confidence interval: 0.77, 0.98). In head-on collisions involving only passenger cars, the adjusted risk ratio was 1.04 (95% confidence interval: 0.85, 1.29). Increased fatality risk for drivers with sled-certified air bags was not observed. A borderline significant interaction between vehicle type and air bag generation suggested that sled-certified air bags may have reduced the risk of dying in head-on collisions among drivers of pickup trucks. PMID:18079131

  13. Implementation and validation of thoracic side impact injury prediction metrics in a human body model.

    PubMed

    Golman, Adam J; Danelson, Kerry A; Gaewsky, James P; Stitzel, Joel D

    2015-08-01

    This study's purpose was to implement injury metrics into the Total Human Model for Safety (THUMS) mirroring the spinal accelerometers, rib accelerometers and chest band instrumentation from two lateral post-mortem human subject sled test configurations. In both sled configurations, THUMS contacted a flat rigid surface (either a wall or beam) at 6.7 m/s. Sled A maximum simulated wall forces for the thorax, abdomen and pelvis were 7.1, 5.0 and 10.0 kN versus 5.7 ± 0.8, 3.4 ± 1.2 and 6.2 ± 2.7 kN experimentally. Sled B maximum simulated beam forces for the torso and pelvis were 8.0 and 7.6 kN versus 8.5 ± 0.2 and 7.9 ± 2.5 kN experimentally. Quantitatively, force magnitude contributed more to variation between simulated and experimental forces than phase shift. Acceleration-based injury metrics were within one standard deviation of experimental means except for the lower spine in the rigid wall sled test. These validated metrics will be useful for quantifying occupant loading conditions and calculating injury risks in various loading configurations. PMID:24520849

  14. Development and validation of a computer crash simulation model of an occupied adult manual wheelchair subjected to a frontal impact.

    PubMed

    Dsouza, R; Bertocci, G

    2010-04-01

    Wheelchairs are primarily designed for mobility and are not necessarily intended for use as motor vehicle seats. However, many wheelchairs serve as vehicle seats for individuals unable to transfer to a vehicle seat. Subjecting wheelchairs to sled testing, in part establishes the crashworthiness of wheelchairs used as motor vehicle seats. Computer simulations provide a supplemental approach for sled testing, to assess wheelchair response and loading under crash conditions. In this study a nonlinear, dynamic, computer model was developed and validated to simulate a wheelchair and occupant subjected to a frontal impact test (ANSI/RESNA WC19). This simulation model was developed utilizing data from two frontal impact 20 g/48 km/h sled tests, which consisted of identical, adult manual wheelchairs secured with 4-point tiedowns, occupied with a 50th percentile adult male anthropomorphic test device (ATD), restrained with a 3-point occupant restraint system. Additionally, the model was validated against sled data using visual comparisons of wheelchair and occupant kinematics, along with statistical assessments of outcome measures. All statistical evaluations were found to be within the acceptance criteria, indicating the model's high predictability of the sled tests. This model provides a useful tool for the development of crashworthy wheelchair design guidelines, as well as the development of transit-safe wheelchair technologies. PMID:19251461

  15. Realistic warhead and blast shield testing of chemical energy tandem warhead systems for advanced antitank missiles

    SciTech Connect

    Fradkin, D.B.; Hull, L.M.; Laabs, G.W.

    1990-01-01

    The results of dynamic sled track performance testing of advanced tandem configuration shaped-charge warheads against multiple-reactive-element tank armors are presented. Tandem configurations utilizing both currently fielded and experimental shaped-charge warheads were tested. Sled velocities used were between 400 and 1100 ft/s (Mach number 0.35 to 0.95), typical of the terminal approach velocity of TOW-type antitank missiles. High-speed motion pictures (5000 frames/s) of the sled in operation and a typical mock missile'' warhead package approaching the target are shown. Details of the sled design and fabrication and of the warhead package design and fabrication are presented. Sled track instrumentation is discussed. This instrumentation includes foil make/break switches and associated time interval meters (TIM) and digital delay units (DDU), magnetic Hall-effect transistors for measuring sled trajectory, and flash x-rays (FXR). Methods for timing the x-rays are presented. Schematic functional diagrams of the experimental setups are also given. Evidence of the ability to accurately time the delay between precursor and main warheads for even very long time delays are presented. FXR pictures illustrate the dynamics of the interaction of the jets with various target elements. The interaction dynamics of the jets is discussed in relation to the overall penetration performance of the tandem warhead. The use of x-ray fluorescence spectroscopy to help diagnose interaction dynamics is illustrated. The results of a test utilizing the missile propulsion rocket motor as a blast shield is presented in this paper. 2 refs., 22 figs.

  16. Comparisons between in situ measurements of the magnetic shadowing of high energy ions at Mars and hybrid model simulations, using contemporary particle and field measurements to define the upstream interplanetary conditions

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, S.; Kallio, E.; Alho, M.; Jarvinen, R.; Afonin, V.

    2012-04-01

    Energetic particle data recorded by the SLED instrument aboard Phobos-2 while in circular orbit about Mars in March, 1989 showed the presence of magnetic shadowing. A 3-D, self consistent, hybrid model (HYB-Mars) supplemented by test particle simulations was developed to study the response of the Martian plasma environment to solar disturbances and to interpret, in particular, the SLED observations. The magnetic and electric fields, as well as the properties of high energy ions, present at Mars under conditions of extreme solar disturbance can be derived from HYB-Mars. Our initial study [McKenna-Lawlor et al., EPS 2011, in press] showed that the HYB-Mars model predicted an already well-documented plasma phenomenon at the planet, namely 'sw-flow shadowing (identified in the measurements of the ASPERA (plasma) experiment aboard Phobos-2). HYB further, importantly, predicted the occurrence of magnetic shadowing which is qualitatively similar to that recorded by SLED. The simulations in addition suggested that the configuration of a magnetic shadow depends on the pertaining solar wind density and velocity, and on the magnitude and direction of the interplanetary magnetic field. The present work presents a more detailed study where plasma and magnetic field inputs to the HYB model come from measurements made aboard Phobos-2 contemporaneously with the SLED observations. In this way it is possible to realistically match the upstream interplanetary conditions with the configuration of the magnetic shadow recorded at various energies in the SLED data. One-to-one comparisons between the SLED observations and simulated high energy H+ fluxes will be presented in this context and similarities and differences between the observations and simulations discussed.

  17. A theory for the excitation of CO in star-forming galaxies

    NASA Astrophysics Data System (ADS)

    Narayanan, Desika; Krumholz, Mark R.

    2014-08-01

    Observations of molecular gas in high-z star-forming galaxies typically rely on emission from CO lines arising from states with rotational quantum numbers J > 1. Converting these observations to an estimate of the CO J = 1-0 intensity, and thus inferring H2 gas masses, requires knowledge of the CO excitation ladder or spectral line energy distribution (SLED). The few available multi-J CO observations of galaxies show a very broad range of SLEDs, even at fixed galaxy mass and star formation rate (SFR), making the conversion to J = 1-0 emission and hence molecular gas mass highly uncertain. Here, we combine numerical simulations of disc galaxies and galaxy mergers with molecular line radiative transfer calculations to develop a model for the physical parameters that drive variations in CO SLEDs in galaxies. An essential feature of our model is a fully self-consistent computation of the molecular gas temperature and excitation structure. We find that, while the shape of the SLED is ultimately determined by difficult-to-observe quantities such as the gas density, temperature and optical depth distributions, all of these quantities are well correlated with the galaxy's mean star formation rate surface density (ΣSFR), which is observable. We use this result to develop a model for the CO SLED in terms of ΣSFR, and show that this model quantitatively reproduces the SLEDs of galaxies over a dynamic range of ˜200 in SFR surface density, at redshifts from z = 0 to 6. This model should make it possible to significantly reduce the uncertainty in deducing molecular gas masses from observations of high-J CO emission.

  18. Planned investigation of energetic particle populations (approximately 20-500 keV) in the close Martian environment

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, S.; Rusznyak, P.; Gringauz, K.; Klimenko, I.; Lutsenko, V.; Verigin, M.; Korth, A.; Richter, A.; Fischer, S.; Polasek, C.

    1995-04-01

    Energetic particle observations made by the Irish SLED instrument on the Phobos 2 spacecraft in 1989 have revealed the presence, within the overall energy range less than 30 keV - greater than 3.2 MeV, of variously located energetic particle populations in the close Marian environment. The signatures of characteristic boundaries have also been recorded for the first time in energetic particles in the distant Martian magnetotail. The new SLED-II instrument on the Mars-94 Mission is designed to study in detail, with 4 pi measurement capability, these and other energetic particle phenomena at Mars, while operating, over an extended period, at low altitudes above the planet.

  19. Alaska Women in the Iditarod.

    ERIC Educational Resources Information Center

    Stout, Peg

    This instructional booklet features biographical stories of Alaskan women who have raced and participated in the annual Iditarod Sled Dog Race. The Iditarod race covers over 1,049 miles from Anchorage to Nome and attracts racers from all over the world. A team consists of 12 to 18 dogs and their trainer or musher. The first Iditarod took place in…

  20. HABITAT ASSOCIATIONS OF LARVAL FISH IN A LAKE SUPERIOR COASTAL WETLAND

    EPA Science Inventory

    Habitat associations of larval fishes in Great Lakes coastal wetlands (GLCW) are not well documented. To determine the distribution of larval fish in coastal wetlands with regard to location and vegetation characteristics, we used a larval tow-sled to sample four macrohabitat typ...

  1. Premature ignition of a rocket motor.

    SciTech Connect

    Moore, Darlene Ruth

    2010-10-01

    During preparation for a rocket sled track (RST) event, there was an unexpected ignition of the zuni rocket motor (10/9/08). Three Sandia staff and a contractor were involved in the accident; the contractor was seriously injured and made full recovery. The data recorder battery energized the low energy initiator in the rocket.

  2. 75 FR 50958 - Federal Motor Vehicle Safety Standards; Motorcoach Definition; Occupant Crash Protection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ... dummies during the crash, and the structural integrity of the seats, floor and bus. The sled tests (crash... total cost of adding belts and making structural changes to the motorcoach floor would be approximately... weight to the motorcoach. Weight would vary depending upon the needed structural changes, and...

  3. It's Time to Play

    MedlinePlus

    ... on a sled. Make snow angels. When It's Hot, Hot, Hot Yikes — it's hot outside, everyone is sweaty, and your legs are ... water , even if you don't feel thirsty. Hot temperatures make you sweat more when you're ...

  4. 14. ELEVATED CAMERA STAND IN FOREGROUND, FIRING CONTROL BLOCKHOUSE (BLDG. ...

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

    14. ELEVATED CAMERA STAND IN FOREGROUND, FIRING CONTROL BLOCKHOUSE (BLDG. 0545) IN CENTER, AIR SUPPLY BUILDING AND PROTECTIVE BERM IN BACKGROUND. Looking north northeast from Camera Road. - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  5. Hey! A Louse Bit Me!

    MedlinePlus

    ... Sledding, Skiing, Snowboarding, Skating Crushes What's a Booger? Hey! A Louse Bit Me! KidsHealth > For Kids > Hey! A Louse Bit Me! Print A A A ... For Kids For Parents MORE ON THIS TOPIC Hey! A Gnat Bit Me! Hey! A Flea Bit ...

  6. Hey! A Chigger Bit Me!

    MedlinePlus

    ... Sledding, Skiing, Snowboarding, Skating Crushes What's a Booger? Hey! A Chigger Bit Me! KidsHealth > For Kids > Hey! A Chigger Bit Me! Print A A A ... For Kids For Parents MORE ON THIS TOPIC Hey! A Fire Ant Stung Me! Hey! A Gnat ...

  7. COMPARISON OF TRANSFER OF SURFACE CHLORPYRIFOS RESIDUES FROM CARPET BY THREE DISLODGEABLE RESIDUE METHODS

    EPA Science Inventory

    After chlorpyrifos, which was broadcast-sprayed on carpet, had dried, transfers by the Dow drag sled, the California cloth roller, and the Southwest Research Institute polyurethane foam (PUF) roller were compared. n plush nylon carpet, mean chlorpyrifos transfers were 4.5% by the...

  8. Head impact mechanisms of a child occupant seated in a child restraint system as determined by impact testing.

    PubMed

    Yoshida, Ryoichi; Okada, Hiroshi; Nomura, Mitsunori; Mizuno, Koji; Tanaka, Yoshinori; Hosokawa, Naruyuki

    2011-11-01

    In side collision accidents, the head is the most frequently injured body region for child occupants seated in a child restraint system (CRS). Accident analyses show that a child's head can move out of the CRS shell, make hard contact with the vehicle interior, and thus sustain serious injuries. In order to improve child head protection in side collisions, it is necessary to understand the injury mechanism of a child in the CRS whose head makes contact with the vehicle interior. In this research, an SUV-to-car oblique side crash test was conducted to reconstruct such head contacts. A Q3s child dummy was seated in a CRS in the rear seat of the target car. The Q3s child dummy's head moved out beyond the CRS side wing, moved laterally, and made contact with the side window glass and the doorsill. It was demonstrated that the hard head contact, which produced a high HIC value, could occur in side collisions. A series of sled tests was carried out to reproduce the dummy kinematic behavior observed in the SUV-to-car crash test, and the sled test conditions such as sled angle, ECE seat slant angle and velocity-time history that duplicated the kinematic behavior were determined. A parametric study also was conducted with the sled tests; and it was found that the impact angle, harness slack, chest clip, and the CRS side wing shape affected the torso motion and head contact with the vehicle interior. PMID:22869307

  9. Denakenaga' for Children. Lesson Plans for Teaching Denakenaga' (Minto-Nenana Tanana) to Children in Elementary Grades.

    ERIC Educational Resources Information Center

    Thompson, Chad; Frank, Ellen

    This curriculum for elementary school-level instruction in Denakenaga' is intended for development of oral native language skills. Included are plans for 60 25-minute lessons, arranged in 11 units: basic conversation; food and eating; hunting and animals; clothing and morning routine; weather; body parts; dogs and sleds; numbers; the village;…

  10. The ESTER particle and plasma analyzer complex for the phobos mission

    NASA Astrophysics Data System (ADS)

    Afonin, V. V.; McKenna-Lawlor, S.; Kiraly, P.; Marsden, R.; Richter, A.; Rusznyak, P.; Shutte, N. M.; Szabo, L.; Szalai, S.; Szucs, I. T.; Varhalmi, L.; Witte, M.

    1990-05-01

    The ESTER particle and plasma analyzer system for the Phobos Mission comprised a complex of three instruments (LET, SLED and HARP) serviced by a common Data Processing Unit. An account is provided of this complex, its objectives and excellent performance in space.

  11. Doggone Good Lessons.

    ERIC Educational Resources Information Center

    Raack, Lenaya

    1999-01-01

    Describes a teacher's experiences developing and implementing a three-week interdisciplinary unit for fourth grade students that revolves around the Alaskan Iditarod sled dog race. Students read about the race history, figure out a racing budget, learn about animal breeding and care, and follow the actual progress of the racing teams via Internet…

  12. Space adaptation syndrome experiments (8-IML-1)

    NASA Technical Reports Server (NTRS)

    Watt, D.

    1992-01-01

    A set of seven experiments will study adaptation of the human nervous system to weightlessness. Particular emphasis will be placed on the vestibular and proprioceptive systems. The experiments are as follows: the sled/H-reflex; rotation/vestibulo-ocular reflex; the visual stimulator experiment; proprioception (relaxed) experiment; proprioception (active) experiment; proprioception (illusion) experiment; and tactile acuity.

  13. 36 CFR 1002.19 - Winter activities.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Winter activities. 1002.19 Section 1002.19 Parks, Forests, and Public Property PRESIDIO TRUST RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 1002.19 Winter activities. (a) Skiing, snowshoeing, ice skating, sledding,...

  14. 36 CFR 1002.19 - Winter activities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Winter activities. 1002.19 Section 1002.19 Parks, Forests, and Public Property PRESIDIO TRUST RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 1002.19 Winter activities. (a) Skiing, snowshoeing, ice skating, sledding,...

  15. Understanding Complex Ecologies: An Investigation of Student Experiences in Adventure Learning Programs

    ERIC Educational Resources Information Center

    Koseoglu, Suzan; Doering, Aaron

    2011-01-01

    The GoNorth! Adventure Learning (AL) Series delivered educational programs about global climate change and sustainability from 2006 to 2010 via a hybrid-learning environment that included a curriculum designed with activities that worked in conjunction with the travels of Team GoNorth! as they dog sledded throughout the circumpolar Arctic. This…

  16. Development and validation of a frontal impact 6-year-old occupant and wheelchair computer model.

    PubMed

    Ha, DongRan; Bertocci, Gina; Jategaonkar, Rohit

    2007-01-01

    Many children with disabilities use their wheelchair as a vehicle seat when traveling. To date, few studies have focused on pediatric wheelchair users in transit. A computer model representing a manual pediatric wheelchair seated with a Hybrid III 6-year-old anthropomorphic test device subjected to a 20-g/48-kph (30-mph) frontal crash was developed in MADYMO. The wheelchair was secured using a 4-point tiedown system, and the occupant was restrained using a 3-point belt system. The time history profiles of the computer model were tuned to those of the sled tests. The peak value for key variables was compared between the sled tests and the model. To evaluate model variable time histories, Pearson's correlation coefficients (r) between the sled test and the model outcome measures were determined. The correlation coefficients ranged from .86 to .95, with an average r of .91. This indicates that there are "high" correlations between the model and sled tests across all variables. The pediatric wheelchair model developed and validated in this study will provide a foundation for studying the response of a manual pediatric wheelchair in frontal impacts and associated injury risks for pediatric wheelchair users. PMID:18335711

  17. STEMEdhub: Supporting STEM Education Initiatives via the HUBzero Platform

    ERIC Educational Resources Information Center

    Lehman, James D.; Ertmer, Peggy A.; Bessenbacher, Ann M.

    2015-01-01

    Built as one of 60+ hubs on the HUBzero platform, STEMEdhub was developed in 2011 as a resource for research, education, and collaboration in STEM education. The hub currently supports 82 different groups. In this article, the authors describe two specific groups (SLED and AAU) that are taking advantage of numerous communication and resource tools…

  18. Hemodiafiltration Decreases Serum Levels of Inflammatory Mediators in Severe Leptospirosis: A Prospective Study

    PubMed Central

    Cleto, Sérgio Aparecido; Rodrigues, Camila Eleutério; Malaque, Ceila Maria; Sztajnbok, Jaques; Seguro, Antônio Carlos; Andrade, Lúcia

    2016-01-01

    Background Leptospirosis is a health problem worldwide. Its most severe form is a classic model of sepsis, provoking acute respiratory distress syndrome (ARDS) and acute kidney injury (AKI), with associated mortality that remains unacceptably high. We previously demonstrated that early initiation of sustained low-efficiency dialysis (SLED) followed by daily SLED significantly decreases mortality. However, the mode of clearance can also affect dialysis patient outcomes. Therefore, the objective of this study was to compare the effects of SLED with traditional (diffusive) clearance, via hemodialysis, and SLED with convective clearance, via hemodiafiltration (SLEDf), in patients with severe leptospirosis. Methods In this prospective study, conducted in the intensive care unit (ICU) from 2009 through 2012, we compared two groups—SLED (n = 19) and SLEDf (n = 20)—evaluating demographic, clinical, and biochemical parameters, as well as serum levels of interleukins, up to the third day after admission. All patients received dialysis early and daily thereafter. Results During the study period, 138 patients were admitted to our ICU with a diagnosis of leptospirosis; 39 (36 males/3 females) met the criteria for ARDS and AKI. All patients were on mechanical ventilation and were comparable in terms of respiratory parameters. Mortality did not differ between the SLEDf and SLED groups. However, post-admission decreases in the serum levels of interleukin (IL)-17, IL-7, and monocyte chemoattractant protein-1 were significantly greater in the SLEDf group. Direct bilirubin and the arterial oxygen tension/fraction of inspired oxygen ratio were significantly higher in the SLED group. We identified the following risk factors (sensitivities/specificities) for mortality in severe leptospirosis: age ≥ 55 years (67%/91%); serum urea ≥ 204 mg/dl (100%/70%); creatinine ≥ 5.2 mg/dl (100%/58%); Acute Physiology and Chronic Health Evaluation II score ≥ 39.5 (67%/88%); Sequential

  19. The effect of gait approach velocity on the broken escalator phenomenon.

    PubMed

    Tang, K-S; Kaski, D; Allum, J H J; Bronstein, A M

    2013-05-01

    Walking onto a stationary surface previously experienced as moving generates an after-effect commonly known as the "broken escalator" after-effect (AE). This AE represents an inappropriate expression of the locomotor adaptation necessary to step onto the moving platform (or escalator). It is characterised by two main biomechanical components, an increased gait approach velocity (GAV) and a forward trunk overshoot on gait termination. We investigated whether the trunk overshoot and other biomechanical measures are the direct inertial consequence of the increased GAV or whether these are the result of an independent adaptive mechanism. Forty-eight healthy young adults walked onto a movable sled. They performed 5 trials with the sled stationary at their preferred walking velocity (BEFORE trials), 5 with the sled moving (MOVING or adaptation trials), and 5 with the sled stationary again (AFTER trials). For the AFTER trials, subjects were divided into four groups. One group was instructed to walk slowly ("slower"), another with cueing at the BEFORE pace ("metronome"). The third group walked without cueing at the BEFORE pace ("normal"), and the fourth, fast ("faster"). We measured trunk pitch angle, trunk linear horizontal displacement, left shank pitch angular velocity and surface EMG from lower leg and trunk muscles. In the AFTER trials, an AE was observed in these biomechanical measures for all gait speeds, but these were not strongly dependent on GAV. An AE was present even when GAV was not different from that of BEFORE trials. Therefore, we conclude that, although contributary, the trunk overshoot is not the direct consequence of the increased GAV. Instead, it appears to be generated by anticipatory motor activity "just in case" the sled moves, herewith termed a "pre-emptive" postural adjustment. PMID:23468158

  20. Warm molecular gas temperature distribution in six local infrared bright Seyfert galaxies

    NASA Astrophysics Data System (ADS)

    Pereira-Santaella, Miguel; Spinoglio, Luigi; van der Werf, Paul P.; Piqueras López, Javier

    2014-06-01

    We simultaneously analyze the spectral line energy distributions (SLEDs) of CO and H2 of six local luminous infrared (IR) Seyfert galaxies. For the CO SLEDs, we used new Herschel/SPIRE FTS data (from J = 4-3 to J = 13-12) and ground-based observations for the lower-J CO transitions. The H2 SLEDs were constructed using archival mid-IR Spitzer/IRS and near-IR VLT/SINFONI data for the rotational and ro-vibrational H2 transitions, respectively. In total, the SLEDs contain 26 transitions with upper level energies between 5 and 15 000 K. A single, constant density, model (nH2 ~ 104.5-6 cm-3) with a broken power-law temperature distribution reproduces well both the CO and H2 SLEDs. The power-law indices are β1 ~ 1-3 for warm molecular gas (20 K 100 K). We show that the steeper temperature distribution (higher β) for hot molecular gas can be explained by shocks and photodissociation region (PDR) models; however, the exact β values are not reproduced by PDR or shock models alone and a combination of both is needed. We find that the three major mergers among our targets have shallower temperature distributions for warm molecular gas than the other three spiral galaxies. This can be explained by a higher relative contribution of shock excitation, with respect to PDR excitation, for the warm molecular gas in these mergers. For only one of the mergers, IRASF 05189-2524, the shallower H2 temperature distribution differs from that of the spiral galaxies. The presence of a bright active galactic nucleus in this source might explain the warmer molecular gas observed. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

  1. Molecular Gas Heating Mechanisms, and Star Formation Feedback in Merger/Starbursts: NGC 6240 and Arp 193 as Case Studies

    NASA Astrophysics Data System (ADS)

    Papadopoulos, Padelis P.; Zhang, Zhi-Yu; Xilouris, E. M.; Weiss, Axel; van der Werf, Paul; Israel, F. P.; Greve, T. R.; Isaak, Kate G.; Gao, Y.

    2014-06-01

    We used the SPIRE/FTS instrument aboard the Herschel Space Observatory to obtain the Spectral Line Energy Distributions (SLEDs) of CO from J = 4-3 to J = 13-12 of Arp 193 and NGC 6240, two classical merger/starbursts selected from our molecular line survey of local Luminous Infrared Galaxies (L IR >= 1011 L ⊙). The high-J CO SLEDs are then combined with ground-based low-J CO, 13CO, HCN, HCO+, CS line data and used to probe the thermal and dynamical states of their large molecular gas reservoirs. We find the two CO SLEDs strongly diverging from J = 4-3 onward, with NGC 6240 having a much higher CO line excitation than Arp 193, despite their similar low-J CO SLEDs and L FIR/L CO, 1 - 0, L HCN/L CO (J = 1-0) ratios (proxies of star formation efficiency and dense gas mass fraction). In Arp 193, one of the three most extreme starbursts in the local universe, the molecular SLEDs indicate a small amount (~5%-15%) of dense gas (n >= 104 cm-3) unlike NGC 6240 where most of the molecular gas (~60%-70%) is dense (n ~ (104-105) cm-3). Strong star-formation feedback can drive this disparity in their dense gas mass fractions, and also induce extreme thermal and dynamical states for the molecular gas. In NGC 6240, and to a lesser degree in Arp 193, we find large molecular gas masses whose thermal states cannot be maintained by FUV photons from Photon-Dominated Regions. We argue that this may happen often in metal-rich merger/starbursts, strongly altering the initial conditions of star formation. ALMA can now directly probe these conditions across cosmic epoch, and even probe their deeply dust-enshrouded outcome, the stellar initial mass function averaged over galactic evolution.

  2. Interrelationships between different loads in resisted sprints, half-squat 1 RM and kinematic variables in trained athletes.

    PubMed

    Martínez-Valencia, María Asunción; González-Ravé, José M; Santos-García, Daniel Juárez; Alcaraz Ramón, Pedro E; Navarro-Valdivielso, Fernando

    2014-01-01

    Resisted sprint running is a common training method for improving sprint-specific strength. It is well-known that an athlete's time to complete a sled-towing sprint increases linearly with increasing sled load. However, to our knowledge, the relationship between the maximum load in sled-towing sprint and the sprint time is unknown, The main purpose of this research was to analyze the relationship between the maximum load in sled-towing sprint, half-squat maximal dynamic strength and the velocity in the acceleration phase in 20-m sprint. A second aim was to compare sprint performance when athletes ran under different conditions: un-resisted and towing sleds. Twenty-one participants (17.86 ± 2.27 years; 1.77 ± 0.06 m and 69.24 ± 7.20 kg) completed a one repetition maximum test (1 RM) from a half-squat position (159.68 ± 22.61 kg) and a series of sled-towing sprints with loads of 0, 5, 10, 15, 20, 25, 30% body mass (Bm) and the maximum resisted sprint load. No significant correlation (P<0.05) was found between half-squat 1 RM and the sprint time in different loaded conditions. Conversely, significant correlations (P<0.05) were found between maximum load in resisted sprint and sprint time (20-m sprint time, r=-0.71; 5% Bm, r=-0.73; 10% Bm, r=-0.53; 15% Bm, r=-0.55; 20% Bm, r=-0.65; 25% Bm, r=-0.44; 30% Bm, r=-0.63; MaxLoad, r= 0.93). The sprinting velocity significantly decreased by 4-22% with all load increases. Stride length (SL) also decreased (17%) significantly across all resisted conditions. In addition, there were significant differences in stride frequency (SF) with loads over 15% Bm. It could be concluded that the knowledge of the individual maximal load in resisted sprint and the effects on the sprinting kinematic with different loads, could be interesting to determinate the optimal load to improve the acceleration phase at sprint running. PMID:24444204

  3. Gastritis and Gastric Ulcers in Working Dogs

    PubMed Central

    Davis, Michael S.; Williamson, Katherine K.

    2016-01-01

    Gastritis and gastric ulcers are an important cause of morbidity and mortality in canine athletes. Although the majority of scientific work on this condition has been performed in ultraendurance racing sled dogs, this condition has been identified in other canine athletes, including sled dogs competing in shorter events and dogs performing off-leash explosive detection duties. The cause of the syndrome is unknown, but current hypotheses propose a link between exercise-induced hyperthermia and loss of gastric mucosal barrier function as an early event in the pathogenesis. Treatment is focused on prevention of clinical disease using acid secretion inhibitors, such as omeprazole, which has excellent efficacy in controlled clinical studies. PMID:27092307

  4. Technology evaluation of man-rated acceleration test equipment for vestibular research

    NASA Technical Reports Server (NTRS)

    Taback, I.; Kenimer, R. L.; Butterfield, A. J.

    1983-01-01

    The considerations for eliminating acceleration noise cues in horizontal, linear, cyclic-motion sleds intended for both ground and shuttle-flight applications are addressed. the principal concerns are the acceleration transients associated with change in direction-of-motion for the carriage. The study presents a design limit for acceleration cues or transients based upon published measurements for thresholds of human perception to linear cyclic motion. The sources and levels for motion transients are presented based upon measurements obtained from existing sled systems. The approaches to a noise-free system recommends the use of air bearings for the carriage support and moving-coil linear induction motors operating at low frequency as the drive system. Metal belts running on air bearing pulleys provide an alternate approach to the driving system. The appendix presents a discussion of alternate testing techniques intended to provide preliminary type data by means of pendulums, linear motion devices and commercial air bearing tables.

  5. Analysis of ocular torsion data from Space Labs D-1 and SL-1

    NASA Technical Reports Server (NTRS)

    Oman, C. M.

    1990-01-01

    A series of preflight, inflight, and postflight vestibular experiments were conducted on Spacelab missions SL-1 and D-1. Two portions of the investigation, the 'sled' and 'dome' functional objectives, involved recording the torsional motion of human subject's eyes. In the SL-1 sled and dome experiments, preflight and postflight ocular torsion was recorded on 35 mm film using a Nikon motor driven camera (2.6 frames/sec). The film was to be analyzed by measuring the motion of contact lens landmarks using a Hermes senior film scanner. However, an inflight failure of the dome experiment camera flash unit led the crew to utilize the Spacelab video camera as an alternative contingency method for imaging the eye in this FO. A suitable method for analysis of the video data was developed. Results of the analysis are presented.

  6. A new look at deep-sea video

    USGS Publications Warehouse

    Chezar, H.; Lee, J.

    1985-01-01

    A deep-towed photographic system with completely self-contained recording instrumentation and power can obtain color-video and still-photographic transects along rough terrane without need for a long electrically conducting cable. Both the video- and still-camera systems utilize relatively inexpensive and proven off-the-shelf hardware adapted for deep-water environments. The small instrument frame makes the towed sled an ideal photographic tool for use on ship or small-boat operations. The system includes a temperature probe and altimeter that relay data acoustically from the sled to the surface ship. This relay enables the operator to monitor simultaneously water temperature and the precise height off the bottom. ?? 1985.

  7. Mid-J CO Emission in Nearby Seyfert Galaxies

    NASA Astrophysics Data System (ADS)

    Pereira-Santaella, Miguel; Spinoglio, Luigi; Busquet, Gemma; Glenn, Jason; Isaak, Kate; Kamenetzky, Julia; Rangwala, Naseem; Schirm, Maximilien R. P.; Baes, Maarten; Barlow, Michael J.; Boselli, Alessandro; Cooray, Asantha; Cormier, Diane

    2012-12-01

    We study for the first time the complete sub-millimeter spectra (450 GHz to 1550 GHz) of a sample of nearby active galaxies observed with the SPIRE Fourier Transform Spectrometer (SPIRE/FTS) onboard Herschel. The CO ladder (from Jup = 4 to 12) is the most prominent spectral feature in this range. These CO lines probe warm molecular gas that can be heated by ultraviolet photons, shocks, or X-rays originated in the active galactic nucleus or in young star-forming regions. In these proceedings we investigate the physical origin of the CO emission using the averaged CO spectral line energy distribution (SLED) of six Seyfert galaxies. We use a radiative transfer model assuming an isothermal homogeneous medium to estimate the molecular gas conditions. We also compare this CO SLED with the predictions of photon and X-ray dominated region (PDR and XDR) models.

  8. A Herschel Spectroscopic Survey of Warm Molecular Gas in Local Luminous Infrared Galaxies

    NASA Astrophysics Data System (ADS)

    Lu, Nanyao Y.; Zhao, Y.; Xu, C. K.; Gao, Y.; Armus, L.; Appleton, P. N.; Charmandaris, V.; Diaz Santos, T.; Evans, A. S.; Howell, J.; Issak, K.; Iwasawa, K.; Leech, J.; Lord, S. D.; Mazzarella, J. M.; Petric, A.; Sanders, D. B.; Schulz, B.; Surace, J. A.; Van der Werf, P.

    2013-01-01

    We describe an on-going Herschel 194-671 micron spectroscopic survey of a flux-limited sample of 125 local luminous infrared galaxies (LIRGs), targeting primarily at the spectral line energy distribution (SLED) of the CO rotational line emission (from J=4-3 up to J=13-12) from warm and dense molecular gas, the [NII] 205 micron line from ionized gas, and the [CI] 370 and 609 micron lines arising mainly from less dense and colder molecular gas where the CO (J=1-0) line is also strong. We present observational results for the first set of 65 sample galaxies that are more or less point sources with respect to the Herschel beams, and show statistical correlations among the shape of the CO SLED, CO line luminosities, IR dust luminosity, and whether a target is known to harbor AGN or not.

  9. Simultaneous drag and flow measurements of Olympic skeleton athletes

    NASA Astrophysics Data System (ADS)

    Moon, Yae Eun; Digiulio, David; Peters, Steve; Wei, Timothy

    2009-11-01

    The Olympic sport of skeleton involves an athlete riding a small sled face first down a bobsled track at speeds up to 130 km/hr. In these races, the difference between gold and missing the medal stand altogether can be hundredths of a second per run. As such, reducing aerodynamic drag through proper body positioning is of first order importance. To better study the flow behavior and to improve the performance of the athletes, we constructed a static force balance system on a mock section of a bobsled track. Athlete and the sled are placed on the force balance system which is positioned at the exit of an open loop wind tunnel. Simultaneous drag force and DPIV velocity field measurements were made along with video recordings of body position to aid the athletes in determining their optimal aerodynamic body position.

  10. RF modulation studies on an S band pulse compressor

    NASA Astrophysics Data System (ADS)

    Guan, Shu; Feng-Li, Zhao; Shi-Lun, Pei; Ou-Zheng, Xiao

    2016-03-01

    An S band SLED-type pulse compressor has been manufactured by the Institute of High Energy Physics, Beijing, trying to reach 100 MW maximum input power, which means the output peak power is about 500 MW at the phase reversal time. To improve the reliability at very high power, amplitude modulation and phase modulation with flat-top output are considered, and RF modulation studies on the S-band SLED are presented in this paper. Furthermore, a method is developed using the CST Microwave Studio transient solver to simulate the time response of the pulse compressor, which can verify the modulation theory. In addition, the experimental setup was constructed and the flat-top output obtained in low power tests. Both amplitude modulation and phase modulation methods can give flat-top output, and the average power gain for both methods is almost the same. Supported by National Natural Science Foundation of China (11475201)

  11. Transonic and supersonic ground effect aerodynamics

    NASA Astrophysics Data System (ADS)

    Doig, G.

    2014-08-01

    A review of recent and historical work in the field of transonic and supersonic ground effect aerodynamics has been conducted, focussing on applied research on wings and aircraft, present and future ground transportation, projectiles, rocket sleds and other related bodies which travel in close ground proximity in the compressible regime. Methods for ground testing are described and evaluated, noting that wind tunnel testing is best performed with a symmetry model in the absence of a moving ground; sled or rail testing is ultimately preferable, though considerably more expensive. Findings are reported on shock-related ground influence on aerodynamic forces and moments in and accelerating through the transonic regime - where force reversals and the early onset of local supersonic flow is prevalent - as well as more predictable behaviours in fully supersonic to hypersonic ground effect flows.

  12. 28. "CONSTRUCTION PHASING, STATION '0' AREA." Specifications No. OC15775, Drawing ...

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

    28. "CONSTRUCTION PHASING, STATION '0' AREA." Specifications No. OC1-57-75, Drawing No. AF-45-02-19, sheet 3 of 5, D.O. Series No. AF 1439/25, Rev. B. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 5296 Rev. B, Date: 11/13/59. - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  13. 30. "CONSTRUCTION PHASING, STATION '50' AREA." Specifications No. ENG043535775, Drawing ...

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

    30. "CONSTRUCTION PHASING, STATION '50' AREA." Specifications No. ENG-04-353-57-75, Drawing No. AF-4502-19, sheet 4 of 5, D.O. Series No. AF 1439/26. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 5296, Date: 10 NOV. 59. - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  14. Description of a mathematical model and computer simulation of separation of the nose cap from the solid rocket booster

    NASA Technical Reports Server (NTRS)

    Schwaniger, A. J., Jr.; Murphree, H. I.

    1982-01-01

    A system of equations which models the motion of the Solid Rocket Booster Nose Cap upon separation is described. The computer program which utilizes these equations to generate nose cap trajectories is described in detail. Application of the program to simulate a rocket sled test of the nose cap separation is discussed and the results of the applications are presented. With the information given a user should be able to exercise the computer program with a minimum of effort.

  15. 20. HIGH OBLIQUE AERIAL VIEW OF 10,000FOOT HIGH SPEED TRACK, ...

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

    20. HIGH OBLIQUE AERIAL VIEW OF 10,000-FOOT HIGH SPEED TRACK, LOOKING TO SOUTHEAST. THE FIRING CONTROL BUILDING (BUILDING 0502) CAN BE SEEN NEAR THE TRACK AT LOWER RIGHT. (See also HAER NO. CA-234-G). - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  16. NASA satellite to track North Pole expedition

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The proposed expedition of a lone explorer and the use of Nimbus 6 (NASA meteorological research satellite) to track his journey is reported. The journey is scheduled to start March 4, 1978, and will cover a distance of 6.000 Km (3,728 miles) from northern Canada to the North Pole and return, traveling the length of Greenland's isolated interior. The mode of transportation for the explorer will be by dog sled. Instrumentation and tracking techniques are discussed.

  17. Effects of Frequency and Motion Paradigm on Perception of Tilt and Translation During Periodic Linear Acceleration

    NASA Technical Reports Server (NTRS)

    Beaton, K. H.; Holly, J. E.; Clement, G. R.; Wood, Scott J.

    2009-01-01

    Previous studies have demonstrated an effect of frequency on the gain of tilt and translation perception. Results from different motion paradigms are often combined to extend the stimulus frequency range. For example, Off-Vertical Axis Rotation (OVAR) and Variable Radius Centrifugation (VRC) are useful to test low frequencies of linear acceleration at amplitudes that would require impractical sled lengths. The purpose of this study was to compare roll-tilt and lateral translation motion perception in 12 healthy subjects across four paradigms: OVAR, VRC, sled translation and rotation about an earth-horizontal axis. Subjects were oscillated in darkness at six frequencies from 0.01875 to 0.6 Hz (peak acceleration equivalent to 10 deg, less for sled motion below 0.15 Hz). Subjects verbally described the amplitude of perceived tilt and translation, and used a joystick to indicate the direction of motion. Consistent with previous reports, tilt perception gain decreased as a function of stimulus frequency in the motion paradigms without concordant canal tilt cues (OVAR, VRC and Sled). Translation perception gain was negligible at low stimulus frequencies and increased at higher frequencies. There were no significant differences between the phase of tilt and translation, nor did the phase significantly vary across stimulus frequency. There were differences in perception gain across the different paradigms. Paradigms that included actual tilt stimuli had the larger tilt gains, and paradigms that included actual translation stimuli had larger translation gains. In addition, the frequency at which there was a crossover of tilt and translation gains appeared to vary across motion paradigm between 0.15 and 0.3 Hz. Since the linear acceleration in the head lateral plane was equivalent across paradigms, differences in gain may be attributable to the presence of linear accelerations in orthogonal directions and/or cognitive aspects based on the expected motion paths.

  18. EERE's State & Local Energy Data Tool

    ScienceCinema

    Shambarger, Erick; DeCesaro, Jennifer

    2014-06-26

    EERE's State and Local Energy Data (SLED) Tool provides basic energy market information that can help state and local governments plan and implement clean energy projects, including electricity generation; fuel sources and costs; applicable policies, regulations, and financial incentives; and renewable energy resource potential. Watch this video to learn more about the tool and hear testimonials from real users about the benefits of using this tool.

  19. Automatic circuit interrupter

    NASA Technical Reports Server (NTRS)

    Dwinell, W. S.

    1979-01-01

    In technique, voice circuits connecting crew's cabin to launch station through umbilical connector disconnect automatically unused, or deadened portion of circuits immediately after vehicle is launched, eliminating possibility that unused wiring interferes with voice communications inside vehicle or need for manual cutoff switch and its associated wiring. Technique is applied to other types of electrical actuation circuits, also launch of mapped vehicles, such as balloons, submarines, test sleds, and test chambers-all requiring assistance of ground crew.

  20. Practical use of high-speed cameras for research and development within the automotive industry: yesterday and today

    NASA Astrophysics Data System (ADS)

    Steinmetz, Klaus

    1995-05-01

    Within the automotive industry, especially for the development and improvement of safety systems, we find a lot of high accelerated motions, that can not be followed and consequently not be analyzed by human eye. For the vehicle safety tests at AUDI, which are performed as 'Crash Tests', 'Sled Tests' and 'Static Component Tests', 'Stalex', 'Hycam', and 'Locam' cameras are in use. Nowadays the automobile production is inconceivable without the use of high speed cameras.

  1. Pickup ions near Mars associated with escaping oxygen atoms

    NASA Astrophysics Data System (ADS)

    Cravens, T. E.; Hoppe, A.; Ledvina, S. A.; McKenna-Lawlor, S.

    2002-08-01

    Ions produced by ionization of Martian neutral atoms or molecules and picked up by the solar wind flow are expected to be an important ingredient of the Martian plasma environment. Significant fluxes of energetic (55-72 keV) oxygen ions were recorded in the wake of Mars and near the bow shock by the solar low-energy detector (SLED) charged particle detector onboard the Phobos 2 spacecraft. Also, copious fluxes of oxygen ions in the ranges 0.5-25 and 0.01-6 keV/q were detected in the Martian wake by the Automatic Space Plasma Experiment with Rotating Analyzer (ASPERA) instrument on Phobos 2. This paper provides a quantitative analysis of the SLED energetic ion data using a test particle model in which one million ion trajectories were numerically calculated. These trajectories were used to determine the ion flux as a function of energy in the vicinity of Mars for conditions appropriate for Circular Orbit 42 of Phobos 2. The electric and magnetic fields required by the test particle model were taken from a three-dimensional magnetohydrodynamic (MHD) model of the solar wind interaction with Mars. The ions were started at rest with a probability proportional to the density expected for exospheric hot oxygen. The test particle model supports the identification of the ions observed in channel 1 of the SLED instrument as pick-up oxygen ions that are created by the ionization of oxygen atoms in the distant part of the exosphere. The flux of 55-72 keV oxygen ions near the orbit of the Phobos 2 should be proportional to the oxygen density at radial distances from Mars of about 10 Rm (Martian radii) and hence proportional to the direct oxygen escape rate from Mars that is an important part of the overall oxygen loss rate at Mars. The modeled energetic oxygen fluxes also exhibit a spin modulation as did the SLED fluxes during Circular Orbit 42.

  2. EERE's State & Local Energy Data Tool

    SciTech Connect

    Shambarger, Erick; DeCesaro, Jennifer

    2014-06-23

    EERE's State and Local Energy Data (SLED) Tool provides basic energy market information that can help state and local governments plan and implement clean energy projects, including electricity generation; fuel sources and costs; applicable policies, regulations, and financial incentives; and renewable energy resource potential. Watch this video to learn more about the tool and hear testimonials from real users about the benefits of using this tool.

  3. 25. "GAFFTC 19 OCT 60, BLAST EFFECTS ON AIRFOILS, STATIC ...

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

    25. "G-AFFTC 19 OCT 60, BLAST EFFECTS ON AIRFOILS, STATIC RUN 5." View of track rail mounting and the water brake trough at 20,000-foot track. Looking northeast. File no. 12,358-60. - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  4. The development of a flight termination parachute system for a 1900 lb payload

    SciTech Connect

    Waye, D.E.

    1997-04-01

    A 30-ft-diameter ringslot/solid parachute was designed, developed, and tested at Sandia National Laboratories as the major component of a flight termination system required for a 1900-lb gliding delivery platform. Four full-scale sled tests were performed to validate the design models of the parachute, determine reefing line length, demonstrate structural adequacy of the parachute materials, and demonstrate that performance met the design requirements.

  5. Development of the parachute recovery system for the LBRV-2 reentry vehicle

    SciTech Connect

    Pepper, W.B.

    1983-10-01

    A 6.44-ft-dia ribbon parachute with no reefing has been developed for recovery for the 130-lb LBRV-2 reentry nose cone. This report presents the results of five sled-launched, free-flight tests and of an operational recovery at velocities of 600 to 875 ft/s with corresponding dynamic pressures of 340 to 766 lb/ft/sup 2/.

  6. Design and characterization of a mixed-signal PCB for digital-to-analog conversion in a modular and scalable infrared scene projector

    NASA Astrophysics Data System (ADS)

    Benedict, Jacob

    Infra-red (IR) sensors have proven instrumental in a wide variety of fields from military to industrial applications. The proliferation of IR sensors has spawned an intense push for technologies that can test and calibrate the multitudes of IR sensors. One such technology, IR scene projection (IRSP), provides an inexpensive and safe method for the testing of IR sensor devices. Previous efforts have been conducted to develop IRSPs based on super-lattice light emitting diodes (SLEDS). A single-color 512x512 SLEDs system has been developed, produced, and tested as documented in Corey Lange's Master's thesis, and a GOMAC paper by Rodney McGee [1][2]. Current efforts are being undergone to develop a two-color 512x512 SLEDs system designated (TCSA). The following thesis discusses the design and implementation of a custom printed circuit board (PCB), known as the FMC 4DAC, that contains both analog and digital signals. Utilizing two 16-bit digital-to-analog converters (DAC) the purpose of the board is to provide four analog current output channels for driving the TCSA system to a maximum frame rate of 1 kHz. In addition, the board supports a scalable TCSA system architecture. Several copies of the board can be run in parallel to achieve a range of analog channels between 4 and 32.

  7. Impact loading of the lumbar spine during football blocking.

    PubMed

    Gatt, C J; Hosea, T M; Palumbo, R C; Zawadsky, J P

    1997-01-01

    The purpose of our study was to determine the impact force to the lumbar spine when football players hit a blocking sled. We quantified the loads at the L4-5 motion segment throughout the blocking sequence. Five Division I-A college football linemen were subjects for our study. Kinematic data were obtained while the subjects hit a blocking sled instrumented with a force plate. Three plane forces were then calculated from these data. The average impact force measured at the blocking sled was 3013 +/- 598 N. The average peak compression force at the L4-5 motion segment was 8679 +/- 1965 N. The average peak anteroposterior shear force was 3304 +/- 1116 N, and the average peak lateral shear force was 1709 +/- 411 N. The magnitude of the loads on the L4-5 motion segment during football blocking exceed those determined during fatigue studies to cause pathologic changes in both the lumbar disk and the pars interarticularis. These data suggest that the mechanics of repetitive blocking may be responsible for the increased incidence of lumbar spine injury incurred by football linemen. PMID:9167810

  8. Miscible and immiscible experiments on the Rayleigh-Taylor instability using simultaneous planar laser induced fluorescence and backlight visualization.

    NASA Astrophysics Data System (ADS)

    Mokler, Matthew; Roberts, Michael; Jacobs, Jeffrey

    2012-11-01

    Incompressible Rayleigh-Taylor instability experiments are presented in which two stratified liquids having Atwood number of 0.2 are accelerated in a vertical linear induction motor driven drop tower. A test sled having only vertical freedom of motion contains the experiment tank and visualization equipment. The sled is positioned at the top of the tower within the linear motors and accelerated downward causing the initially stable interface to be unstable and allowing the Rayleigh-Taylor instability to develop. Experiments are presented with and without forced initial perturbations produced by vertically oscillating the test sled prior to the start of acceleration. Half of the experimental tank is visualized using a 445nm laser light source that illuminates a fluorescent dye mixed in one of the fluids. The other half is illuminated with a white backlight. The resulting images are recorded using a monochromatic high speed video camera allowing for the measurement of spike and bubble mixing layer growth rates for both visualization techniques in a single experiment.

  9. Miscible and immiscible experiments on the Rayleigh-Taylor instability using planar laser induced fluorescence visualization

    NASA Astrophysics Data System (ADS)

    Mokler, Matthew; Roberts, Michael; Jacobs, Jeffrey

    2013-11-01

    Incompressible Rayleigh-Taylor instability experiments are presented in which two stratified liquids having Atwood number of 0.2 are accelerated in a vertical linear induction motor driven drop tower. A test sled having only vertical freedom of motion contains the experiment tank and visualization equipment. The sled is positioned at the top of the tower within the linear induction motors and accelerated downward causing the initially stable interface to be unstable and allowing the Rayleigh-Taylor instability to develop. Forced and unforced experiments are conducted using both immiscible and miscible liquid combinations. Forced initial perturbations are produced by vertically oscillating the test sled prior to the start of acceleration. The interface is visualized using a 445 nm laser light source that illuminates a fluorescent dye mixed in one of the fluids. The resulting fluorescent images are recorded using a monochromatic high speed video camera. The laser beam is synchronously swept across the fluorescent fluid, at the frame rate of the camera, exposing a single plane of the interface allowing for the measurement of spike and bubble growth. Comparisons between miscible and immiscible mixing layer distributions are made from the resulting interface concentration profiles.

  10. Mapping and characterisation of the inter-reefal benthic assemblages of the Torres Strait

    NASA Astrophysics Data System (ADS)

    Haywood, M. D. E.; Pitcher, C. R.; Ellis, N.; Wassenberg, T. J.; Smith, G.; Forcey, K.; McLeod, I.; Carter, A.; Strickland, C.; Coles, R.

    2008-09-01

    A comprehensive survey of the benthic assemblages of the Torres Strait was conducted in order to provide critical baseline information for regional marine planning, assessing the environmental sustainability of fisheries and understanding the ecosystems of the region. Over 150 sites throughout the region were sampled with a modified prawn trawl, towed underwater video, pipe dredge and epibenthic sled. This manuscript provides a broad overview of the activities undertaken and data collected. Two thousand three hundred and seventy-two different nominal species were sampled by the trawl and sled, only 728 by both gears. The towed video was not able to provide the same level of taxonomic resolution of epibenthic taxa, but was particularly useful in areas where the seabed was too rough to be sampled. Data from the trawl, sled and video were combined to characterise the epibenthic assemblages of the region. Data from the towed video was also used to provide a characterisation of the inter-reefal benthic habitats, which was then analysed in combination with physical covariate data to examine relationships between the two. Levels of mud and gravel in the sediments, trawling effort and seabed current stress were the covariates most significantly correlated with the nature of the seabed habitats.

  11. Comparative Performance of Rear Facing Child Restraint Systems on the CMVSS 213 Bench and Vehicle Seats

    PubMed Central

    Tylko, Suzanne; Locey, Caitlin M.; Garcia-Espana, J. Felipe; Arbogast, Kristy B.; Maltese, Matthew R.

    2013-01-01

    The purpose of this study was to compare the dynamic response of rear-facing child restraint systems (RFCRS) installed on the CMVSS 213 sled bench and a selection of vehicle seats. Thirty-six sled tests were conducted: three models of rear facing CRS with an anthropomorphic test device (ATD) representing a 12 month old child (CRABI) were affixed via lower anchors (LATCH), 3 point belt without CRS base, and 3 point belt with CRS base to one of three vehicle seats or the CMVSS 213 bench seat. All CRS were subjected to an identical sled acceleration pulse. Two types of matched pair analysis: “bench-to-vehicle” and “method of attachment” were conducted. Statistically significant differences were observed in the kinematic responses of the ATD and the CRS. This is the first study to quantify differences between the regulatory bench and vehicle seats on a system level and evaluate the influence of attachment method. Our results show that the difference in RFCRS forward excursion between 3-point belt with base and LATCH installations was between 1 and 7 percent on the bench and 22 to 76 percent on the vehicle seats. When evaluating the dynamic performance of RFCRS, the use of real vehicle seats from vehicles that commonly carry children may provide valuable insight. The findings would require further confirmation using a broader selection of RFCRS and vehicle seats, before generalizable conclusions can be drawn. PMID:24406967

  12. Herschel-SPIRE spectroscopy of nearby Seyfert galaxies

    NASA Astrophysics Data System (ADS)

    Sacchi, N.; Spinoglio, L.; Wilson, C. D.; Kamenetzky, J.; Rangwala, N.; Rykala, A.; Isaak, K. G.; Bendo, G. J.; Bradford, M.; Glenn, J.; Maloney, P. R.; Schirm, M. R. P.; Auld, R.; Baes, M.; Barlow, M. J.; Bock, J. J.; Boselli, A.; Buat, V.; Castro-Rodriguez, N.; Chanial, P.; Charlot, S.; Ciesla, L.; Clements, D. L.; Cooray, A.; Cormier, D.; Cortese, L.; Davies, J. I.; Dwek, E.; Eales, S. A.; Elbaz, D.; Galametz, M.; Galliano, F.; Gear, W. K.; Gomez, H. L.; Griffin, M.; Hony, S.; Levenson, L. R.; Lu, N.; Madden, S.; O'Halloran, B.; Okumura, K.; Oliver, S.; Page, M. J.; Panuzzo, P.; Papageorgiou, A.; Parkin, T. J.; Perez-Fournon, I.; Pohlen, M.; Rigby, E. E.; Roussel, H.; Sauvage, M.; Schulz, B.; Smith, M. W. L.; Stevens, J. A.; Sundar, S.; Symeonidis, M.; Trichas, M.; Vaccari, M.; Vigroux, L.; Wozniak, H.; Wright, G. S.; Zeilinger, W. W.

    2011-05-01

    We present the 450-1550 GHz spectra of three nearby Seyfert galaxies (NGC1068, NGC7130 and NGC7582) taken with the Herschel SPIRE FTS. For the case of NGC1068 we reconstruct the nuclear spectral line energy distribution (SLED) of the CO lines, applying nonLTE radiative transfer and a Bayesian likelihood analysis to estimate the physical properties of the molecular gas in the circumnuclear region. Groundbased observations of the low-J transitions with high (few arcsec) angular resolution are required to reconstruct the nuclear SLED avoiding contamination from colder molecular gas on larger galactic scales. We find evidence for a very warm molecular gas component with a density ~10^3.9 cm-3, similar to that found in previous works (Papadopoulos & Seaquist 1999, Usero et al. 2004, Kamenetzky et al. 2011), but with a much higher temperature (~ 550 K instead of 20-160 K). The higher-J transitions of CO are compatible with being excited in X-ray dissociation regions (XDR). However, in order to explain the entire CO SLED a comparable contribution from photodissociation regions (PDR) is required.

  13. The CO-H2 conversion factor and the CO excitation ladder

    NASA Astrophysics Data System (ADS)

    Christian, Joel Robert; Narayanan, Desika

    2015-01-01

    Indirect measurements of molecular hydrogen mass are can be made using the CO line intensity. Previous work has shown that the star formation rate surface density can be used to parameterize the conversion factor (XCO). There is further evidence to suggest that the physical conditions which determine the CO spectral line energy distribution (SLED) also determine the conversion factor from CO line intensity to molecular gas mass conversion factor (XCO). Here, we present a series of SPH simulations of idealized galaxies in evolution, focusing on their Giant Molecular Cloud properties. We simulate a range of both disk galaxies and galaxy mergers with a wide range of star formation rates, velocity dispersions, gas metallicities and temperatures. From these varying simulations we perform full radiative transfer calculations with conditions derived from the simulated GMCs. These calculations will determine theoretical values of the conversion factor (XCO) as well as CO SLEDs. We aim to find a relationship between XCO and the CO SLED that will help inform observers in the era of ALMA.

  14. Preferred movement patterns during a simple bouncing task.

    PubMed

    Raburn, Caroline E; Merritt, Kristen J; Dean, Jesse C

    2011-11-15

    Elastic tissues in the human body can store and return mechanical energy passively, reducing the metabolic cost of cyclical movements. However, it is not clear whether humans prefer movement patterns that optimize this storage and return. We investigated the preferred movement pattern during a bouncing task for which non-invasive techniques can identify the resonant frequency, which is the least metabolically costly. We quantified the preferred and resonant bounce frequencies for three mechanical conditions. During 'normal' trials, subjects bounced while reclined on a sled that moves along a track. During 'added mass' trials, mass was added to the sled. During 'added stiffness' trials, a spring was attached between the sled and the supporting frame, parallel to the track. Subsequently, we quantified the preferred bounce frequencies during ischemia, a technique that disrupts the available sensory feedback. Mechanical condition had a significant effect on both the preferred and resonant frequencies. Changes in preferred frequency scaled with resonant frequency, but the preferred frequency was significantly lower than the resonant frequency. These results indicate that humans adapt their preferred bouncing pattern in response to changes in mechanical condition. Humans may prefer a lower than resonant frequency because of an inability to sense metabolic cost during our relatively short trials. In contrast, during ischemia the preferred bounce frequency remained constant even when mechanical condition was varied, indicating that feedback is necessary to adapt the preferred frequency to changes in mechanics. These findings suggest that disrupted sensory feedback may prevent humans from choosing the optimal movement pattern. PMID:22031741

  15. A wireless time synchronized event control system

    NASA Astrophysics Data System (ADS)

    Klug, Robert; Williams, Jonathan; Scheffel, Peter

    2014-05-01

    McQ has developed a wireless, time-synchronized, event control system to control, monitor, and record events with precise timing over large test sites for applications such as high speed rocket sled payload testing. Events of interest may include firing rocket motors and launch sleds, initiating flares, ejecting bombs, ejecting seats, triggering high speed cameras, measuring sled velocity, and triggering events based on a velocity window or other criteria. The system consists of Event Controllers, a Launch Controller, and a wireless network. The Event Controllers can be easily deployed at areas of interest within the test site and maintain sub-microsecond timing accuracy for monitoring sensors, electronically triggering other equipment and events, and providing timing signals to other test equipment. Recorded data and status information is reported over the wireless network to a server and user interface. Over the wireless network, the user interface configures the system based on a user specified mission plan and provides real time command, control, and monitoring of the devices and data. An overview of the system, its features, performance, and potential uses is presented.

  16. Immiscible experiments on the Rayleigh-Taylor instability using simultaneous particle image velocimetry and planar laser induced fluorescence concentration measurements

    NASA Astrophysics Data System (ADS)

    Mokler, Matthew; Jacobs, Jeffrey

    2014-11-01

    Incompressible Rayleigh-Taylor instability experiments are presented in which two stratified liquids having Atwood number of 0.2 are accelerated in a vertical linear induction motor driven drop tower. A test sled having only vertical freedom of motion contains the experiment tank and visualization equipment. The sled is positioned at the top of the tower within the linear induction motors and accelerated downward causing the initially stable interface to be unstable and allowing the Rayleigh-Taylor instability to develop. Forced and unforced experiments are conducted using an immiscible liquid combination. Forced initial perturbations are produced by vertically oscillating the test sled prior to the start of acceleration. The interface is visualized using a 445 nm laser light source that illuminates a fluorescent dye mixed in one of the fluids and aluminum oxide particles dispersed in both fluids. The laser beam is synchronously swept across the fluorescent fluid, at the frame rate of the camera, exposing a single plane of the interface. The resulting images are recorded using a monochromatic high speed video camera. Time dependent velocity and density fields are obtained from the recorded images allowing for 2D full field measurements of turbulent kinetic energy and turbulent mass transport.

  17. Crash simulations of wheelchair-occupant systems in transport.

    PubMed

    Kang, W; Pilkey, W D

    1998-01-01

    A nonlinear multirigid body dynamic computer model has been developed to simulate the dynamic responses of a wheelchair-occupant system in a vehicle during a crash. The occupant, restrained by safety belts, is seated in a wheelchair that is, in turn, tied down in a vehicle. Validated extensively by crash sled tests at three laboratories, this model has been used to predict the responses of wheelchair-occupant systems in various crash environments. To evaluate the crashworthiness of different wheelchair tie-downs, the sensitivity of several design parameters, such as tiedown stiffness, wheel stiffness, and tiedown positions, has been studied using this model, and optimal values of these parameters for the wheelchair-occupant system have been obtained. Moreover, the model has been used to study the sensitivity of crash sled test pulse corridors in an effort to develop a sled test standard. It has been found that an existing ISO corridor allows large variation and should be "tightened." The model was implemented using a version of the multibody dynamic simulator, the Articulated Total Body program. PMID:9505255

  18. Molecular gas heating mechanisms, and star formation feedback in merger/starbursts: NGC 6240 and Arp 193 as case studies

    SciTech Connect

    Papadopoulos, Padelis P.; Zhang, Zhi-Yu; Weiss, Axel; Van der Werf, Paul; Israel, F. P.; Greve, T. R.; Isaak, Kate G.; Gao, Y. E-mail: zyzhang@pmo.ac.cn E-mail: aweiss@mpifr-bonn.mpg.de E-mail: israel@strw.leidenuniv.nl E-mail: kisaak@rssd.esa.int

    2014-06-20

    We used the SPIRE/FTS instrument aboard the Herschel Space Observatory to obtain the Spectral Line Energy Distributions (SLEDs) of CO from J = 4-3 to J = 13-12 of Arp 193 and NGC 6240, two classical merger/starbursts selected from our molecular line survey of local Luminous Infrared Galaxies (L {sub IR} ≥ 10{sup 11} L {sub ☉}). The high-J CO SLEDs are then combined with ground-based low-J CO, {sup 13}CO, HCN, HCO{sup +}, CS line data and used to probe the thermal and dynamical states of their large molecular gas reservoirs. We find the two CO SLEDs strongly diverging from J = 4-3 onward, with NGC 6240 having a much higher CO line excitation than Arp 193, despite their similar low-J CO SLEDs and L {sub FIR}/L {sub CO,} {sub 1} {sub –0}, L {sub HCN}/L {sub CO} (J = 1-0) ratios (proxies of star formation efficiency and dense gas mass fraction). In Arp 193, one of the three most extreme starbursts in the local universe, the molecular SLEDs indicate a small amount (∼5%-15%) of dense gas (n ≥ 10{sup 4} cm{sup –3}) unlike NGC 6240 where most of the molecular gas (∼60%-70%) is dense (n ∼ (10{sup 4}-10{sup 5}) cm{sup –3}). Strong star-formation feedback can drive this disparity in their dense gas mass fractions, and also induce extreme thermal and dynamical states for the molecular gas. In NGC 6240, and to a lesser degree in Arp 193, we find large molecular gas masses whose thermal states cannot be maintained by FUV photons from Photon-Dominated Regions. We argue that this may happen often in metal-rich merger/starbursts, strongly altering the initial conditions of star formation. ALMA can now directly probe these conditions across cosmic epoch, and even probe their deeply dust-enshrouded outcome, the stellar initial mass function averaged over galactic evolution.

  19. Biomechanical and injury response to posterolateral loading from torso side airbags.

    PubMed

    Hallman, Jason J; Yoganandan, Narayan; Pintar, Frank A

    2010-11-01

    This study characterized thoracoabdominal response to posterolateral loading from a seat-mounted side airbag. Seven unembalmed post-mortem human subjects were exposed to ten airbag deployments. Subjects were positioned such that the deploying airbag first contacted the posterolateral thorax between T6 and L1 while stationary (n = 3 x 2 aspects) or while subjected to left lateral sled impact at ΔV = 6.7 m/s (n = 4). Chestband contours were analyzed to quantify deformation direction in the thoracic x-y plane (zero degrees indicating anterior and 180° indicating posterior), magnitude, rate, and viscous response. Skeletal injuries were consistent with posterolateral contact; visceral injuries consisted of renal (n = 1) or splenic (n = 3) lacerations. Deformation direction was transient during sled impact, progressing from 122 ± 5° at deformation onset to 90° following maximum deflection. Angles from stationary subjects progressed from 141 ± 9° to 120°. Peak normalized deflections, peak rates, and VCmax ranges were 0.075 - 0.171, 3.7 - 12.7 m/s, and 0.3 - 0.6 m/s with stationary airbag, respectively; ranges were 0.167 - 0.297, 7.4 - 18.3 m/s, and 0.7 - 3.0 m/s with airbag sled impact, respectively. Peak deflections were measured at angles between 99° - 135° and 98° - 125° for stationary and dynamic conditions, respectively. Because of deflection angle transience and localized injury response, both posterolateral and lateral injury metrics may be required for this boundary condition. Contrasted with flat rigid or anterolateral loading, biomechanical response to side airbag interaction may be augmented by peak normalized deflection or VCmax at 130°. PMID:21512911

  20. Molecular gas properties of the giant molecular cloud complexes in the arms and inter-arms of the spiral galaxy NGC 6946

    NASA Astrophysics Data System (ADS)

    Topal, Selçuk; Bayet, Estelle; Bureau, Martin; Davis, Timothy A.; Walsh, Wilfred

    2014-01-01

    Combining observations of multiple CO lines with radiative transfer modelling is a very powerful tool to investigate the physical properties of the molecular gas in galaxies. Using new observations and literature data, we provide the most complete CO ladders ever generated for eight star-forming regions in the spiral arms and inter-arms of the spiral galaxy NGC 6946, with observations of the CO(1-0), CO(2-1), CO(3-2), CO(4-3), CO(6-5), 13CO(1-0) and 13CO(2-1) transitions. For each region, we use the large velocity gradient assumption to derive beam-averaged molecular gas physical properties, namely the gas kinetic temperature (TK), H2 number volume density (n(H2)) and CO number column density (N(CO)). Two complementary approaches are used to compare the observations with the model predictions: χ2 minimization and likelihood. The physical conditions derived vary greatly from one region to the next: TK = 10-250 K, n(H2) = 102.3-107.0 cm-3 and N(CO) = 1015.0-1019.3 cm-2. The spectral line energy distribution (SLED) in some of these extranuclear regions indicate a star formation activity that is more intense than that at the centre of our own Milky Way. The molecular gas in regions with a large SLED turnover transition (Jmax > 4) is hot but tenuous with a high CO column density, while that in regions with a low SLED turnover transition (Jmax ≤ 4) is cold but dense with a low CO column density. We finally discuss and find some correlations between the physical properties of the molecular gas in each region and the presence of young stellar population indicators (supernova remnants, H II regions, H I holes, etc.).

  1. Molecular and Atomic Line Surveys of Galaxies. I. The Dense, Star-Forming Gas Phase as a Beacon

    NASA Astrophysics Data System (ADS)

    Geach, James E.; Papadopoulos, Padelis P.

    2012-10-01

    We predict the space density of molecular gas reservoirs in the universe and place a lower limit on the number counts of carbon monoxide (CO), hydrogen cyanide (HCN) molecular, and [C II] atomic emission lines in blind redshift surveys in the submillimeter-centimeter spectral regime. Our model uses (1) recently available HCN spectral line energy distributions (SLEDs) of local luminous infrared galaxies (LIRGs, L IR > 1011 L ⊙), (2) a value for epsilonsstarf = SFR/M dense(H2) provided by new developments in the study of star formation feedback on the interstellar medium, and (3) a model for the evolution of the infrared luminosity density. Minimal "emergent" CO SLEDs from the dense gas reservoirs expected in all star-forming systems in the universe are then computed from the HCN SLEDs since warm, HCN-bright gas will necessarily be CO-bright, with the dense star-forming gas phase setting an obvious minimum to the total molecular gas mass of any star-forming galaxy. We include [C II] as the most important of the far-infrared cooling lines. Optimal blind surveys with the Atacama Large Millimeter Array (ALMA) could potentially detect very distant (z ~ 10-12) [C II] emitters in the >=ULIRG galaxy class at a rate of ~0.1-1 hr-1 (although this prediction is strongly dependent on the star formation and enrichment history at this early epoch), whereas the (high-frequency) Square Kilometer Array will be capable of blindly detecting z > 3 low-J CO emitters at a rate of ~40-70 hr-1. The [C II] line holds special promise for detecting metal-poor systems with extensive reservoirs of CO-dark molecular gas where detection rates with ALMA can reach up to 2-7 hr-1 in Bands 4-6.

  2. Predictions for the CO emission of galaxies from a coupled simulation of galaxy formation and photon-dominated regions

    NASA Astrophysics Data System (ADS)

    Lagos, Claudia del P.; Bayet, Estelle; Baugh, Carlton M.; Lacey, Cedric G.; Bell, Tom A.; Fanidakis, Nikolaos; Geach, James E.

    2012-11-01

    We combine the galaxy formation model GALFORM with the photon-dominated region code ucl-pdr to study the emission from the rotational transitions of 12CO (CO) in galaxies from z = 0 to z = 6 in the Λcold dark matter framework. GALFORM is used to predict the molecular (H2) and atomic hydrogen (H I) gas contents of galaxies using the pressure-based empirical star formation relation of Blitz & Rosolowsky. From the predicted H2 mass and the conditions in the interstellar medium, we estimate the CO emission in the rotational transitions 1-0 to 10-9 by applying the ucl-pdr model to each galaxy. We find that deviations from the Milky Way CO-H2 conversion factor come mainly from variations in metallicity, and in the average gas and star formation rate surface densities. In the local universe, the model predicts a CO(1-0) luminosity function (LF), CO-to-total infrared (IR) luminosity ratios for multiple CO lines and a CO spectral line energy distribution (SLED) which are in good agreement with observations of luminous and ultra-luminous IR galaxies. At high redshifts, the predicted CO SLED of the brightest IR galaxies reproduces the shape and normalization of the observed CO SLED. The model predicts little evolution in the CO-to-IR luminosity ratio for different CO transitions, in good agreement with observations up to z ≈ 5. We use this new hybrid model to explore the potential of using colour-selected samples of high-redshift star-forming galaxies to characterize the evolution of the cold gas mass in galaxies through observations with the Atacama Large Millimetre Array.

  3. Biomechanical and Injury Response to Posterolateral Loading from Torso Side Airbags

    PubMed Central

    Hallman, Jason J.; Yoganandan, Narayan; Pintar, Frank A.

    2013-01-01

    This study characterized thoracoabdominal response to posterolateral loading from a seat-mounted side airbag. Seven unembalmed post-mortem human subjects were exposed to ten airbag deployments. Subjects were positioned such that the deploying airbag first contacted the posterolateral thorax between T6 and L1 while stationary (n = 3 × 2 aspects) or while subjected to left lateral sled impact at ΔV = 6.7 m/s (n = 4). Chestband contours were analyzed to quantify deformation direction in the thoracic x–y plane (zero degrees indicating anterior and 180° indicating posterior), magnitude, rate, and viscous response. Skeletal injuries were consistent with posterolateral contact; visceral injuries consisted of renal (n = 1) or splenic (n = 3) lacerations. Deformation direction was transient during sled impact, progressing from 122 ± 5° at deformation onset to 90° following maximum deflection. Angles from stationary subjects progressed from 141 ± 9° to 120°. Peak normalized deflections, peak rates, and VCmax ranges were 0.075 – 0.171, 3.7 – 12.7 m/s, and 0.3 – 0.6 m/s with stationary airbag, respectively; ranges were 0.167 – 0.297, 7.4 – 18.3 m/s, and 0.7 – 3.0 m/s with airbag sled impact, respectively. Peak deflections were measured at angles between 99° – 135° and 98° – 125° for stationary and dynamic conditions, respectively. Because of deflection angle transience and localized injury response, both posterolateral and lateral injury metrics may be required for this boundary condition. Contrasted with flat rigid or anterolateral loading, biomechanical response to side airbag interaction may be augmented by peak normalized deflection or VCmax at 130°. PMID:21512911

  4. Occupant kinematics and shoulder belt retention in far-side lateral and oblique collisions: a parametric study.

    PubMed

    Forman, Jason L; Lopez-Valdes, Francisco; Lessley, David J; Riley, Patrick; Sochor, Mark; Heltzel, Sara; Ash, Joseph; Perz, Rafal; Kent, Richard W; Seacrist, Thomas; Arbogast, Kristy B; Tanji, Hiromasa; Higuchi, Kazuo

    2013-11-01

    In far-side impacts, head contact with interior components is a key injury mechanism. Restraint characteristics have a pronounced influence on head motion and injury risk. This study performed a parametric examination of restraint, positioning, and collision factors affecting shoulder belt retention and occupant kinematics in far-side lateral and oblique sled tests with post mortem human subjects (PMHS). Seven PMHS were subjected to repeated tests varying the D-ring position, arm position, pelvis restraint, pre-tensioning, and impact severity. Each PMHS was subjected to four low-severity tests (6.6 g sled acceleration pulse) in which the restraint or position parameters were varied and then a single higher-severity test (14 g) with a chosen restraint configuration (total of 36 tests). Three PMHS were tested in a purely lateral (90° from frontal) impact direction; 4 were tested in an oblique impact (60° from frontal). All subjects were restrained by a 3-point seatbelt. Occupant motion was tracked with a 3D optoelectric high speed motion capture system. For all restraint configurations, the 60° oblique impact angle was associated with greater lateral head excursion than the 90° impact angle. This unexpected result reflects the increased axial rotation of the torso in the oblique impacts, which allowed the shoulder to displace more relative to the shoulder belt and thus the head to displace more relative to the sled buck. Restraint engagement of the torso and shoulder was actually greater in the purely lateral impacts than in the oblique impacts. Pretensioning significantly reduced lateral head excursion (175 mm average in the low-severity tests across all restraint configurations). PMID:24435738

  5. Autonomous Underwater Vehicle(AUV) and Towed Vehicle Technologies for Under-Ice Hydrothermal Vent Studies at the Gakkel Ridge

    NASA Astrophysics Data System (ADS)

    Singh, H.; Akin, D.; Reves-Sohn, R.; Humphris, S.; Shank, T.; Edmonds, H.

    2006-12-01

    The extreme polar environment presents a unique challenge to the use of the otherwise mature oceanographic technologies associated with Autonomous Underwater Vehicles (AUVs), Remotely Operated Vehicles (ROVs) and towed vehicles. For deep water mapping and sampling applications, ice cover in the arctic is a formidable obstacle. In pursuing our goals to locate, map and sample hydrothermal vents on the Gakkel Ridge, we have built and plan to deploy two AUVs named JAGUAR and PUMA and a towed sampling sled with hydraulically actuated sampling chambers. Our methodologies for working with AUVs in the Arctic differ significantly from standard blue-water operations. Specifically, we have focused on, deploying and calibrating acoustic transponders with the limited mobility imposed by multi-year ice; a far more robust system architecture for dealing with component failures underwater; an autonomous manipulation system on the AUV for capturing sessile biological organisms and geological samples; and a low bandwidth acoustic tether for vehicle status, navigation and mission redirection. Our sampling sled was designed with the premise that the limited mobility associated with working in ice will at best provide us with a few, short opportunities to image and sample on a hydrothermal vent site. To this end our sled is equipped with a suite of imaging and chemical sensors as well as devices for quickly obtaining multiple samples of both sessile and motile biological organisms. We plan to deploy these new technologies during the International Polar Year in 2007 as part of a collaborative international effort to characterize the biological and geological characteristics of hydrothermal venting on the ultra-slow spreading Gakkel Ridge in the eastern Arctic basin.

  6. MOLECULAR AND ATOMIC LINE SURVEYS OF GALAXIES. I. THE DENSE, STAR-FORMING GAS PHASE AS A BEACON

    SciTech Connect

    Geach, James E.; Papadopoulos, Padelis P. E-mail: padelis@mpifr-bonn.mpg.de

    2012-10-01

    We predict the space density of molecular gas reservoirs in the universe and place a lower limit on the number counts of carbon monoxide (CO), hydrogen cyanide (HCN) molecular, and [C II] atomic emission lines in blind redshift surveys in the submillimeter-centimeter spectral regime. Our model uses (1) recently available HCN spectral line energy distributions (SLEDs) of local luminous infrared galaxies (LIRGs, L{sub IR} > 10{sup 11} L{sub Sun }), (2) a value for {epsilon}{sub *} = SFR/M{sub dense}(H{sub 2}) provided by new developments in the study of star formation feedback on the interstellar medium, and (3) a model for the evolution of the infrared luminosity density. Minimal 'emergent' CO SLEDs from the dense gas reservoirs expected in all star-forming systems in the universe are then computed from the HCN SLEDs since warm, HCN-bright gas will necessarily be CO-bright, with the dense star-forming gas phase setting an obvious minimum to the total molecular gas mass of any star-forming galaxy. We include [C II] as the most important of the far-infrared cooling lines. Optimal blind surveys with the Atacama Large Millimeter Array (ALMA) could potentially detect very distant (z {approx} 10-12) [C II] emitters in the {>=}ULIRG galaxy class at a rate of {approx}0.1-1 hr{sup -1} (although this prediction is strongly dependent on the star formation and enrichment history at this early epoch), whereas the (high-frequency) Square Kilometer Array will be capable of blindly detecting z > 3 low-J CO emitters at a rate of {approx}40-70 hr{sup -1}. The [C II] line holds special promise for detecting metal-poor systems with extensive reservoirs of CO-dark molecular gas where detection rates with ALMA can reach up to 2-7 hr{sup -1} in Bands 4-6.

  7. Whole-body response to pure lateral impact.

    PubMed

    Lessley, David; Shaw, Greg; Parent, Daniel; Arregui-Dalmases, Carlos; Kindig, Matthew; Riley, Patrick; Purtsezov, Sergey; Sochor, Mark; Gochenour, Thomas; Bolton, James; Subit, Damien; Crandall, Jeff; Takayama, Shinichi; Ono, Koshiro; Kamiji, Koichi; Yasuki, Tsuyoshi

    2010-11-01

    The objective of the current study was to provide a comprehensive characterization of human biomechanical response to whole-body, lateral impact. Three approximately 50th-percentile adult male PMHS were subjected to right-side pure lateral impacts at 4.3 ± 0.1 m/s using a rigid wall mounted to a rail-mounted sled. Each subject was positioned on a rigid seat and held stationary by a system of tethers until immediately prior to being impacted by the moving wall with 100 mm pelvic offset. Displacement data were obtained using an optoelectronic stereophotogrammetric system that was used to track the 3D motions of the impacting wall sled; seat sled, and reflective targets secured to the head, spine, extremities, ribcage, and shoulder complex of each subject. Kinematic data were also recorded using 3-axis accelerometer cubes secured to the head, pelvis, and spine at the levels of T1, T6, T11, and L3. Chest deformation in the transverse plane was recorded using a single chestband. Following the impact the subject was captured in an energy-absorbing net that provided a controlled non-injurious deceleration. The wall maintained nearly constant velocity throughout the impact event. One of the tested subjects sustained 16 rib fractures as well as injury to the struck shoulder while the other two tested subjects sustained no injuries. The collected response data suggest that the shoulder injury may have contributed to the rib fractures in the injured subject. The results suggest that the shoulder presents a substantial load path and may play an important role in transmitting lateral forces to the spine, shielding and protecting the ribcage. This characterization of whole-body, lateral impact response provides quantified subject responses and boundary condition interactions that are currently unavailable for whole-body, lateral impacts at impact speeds less than 6.7 m/s. PMID:21512913

  8. Determination of peak deflections from human surrogates using chestbands in side impact tests.

    PubMed

    Yoganandan, Narayan; Humm, John R; Pintar, Frank A; Maiman, Dennis J

    2013-08-01

    To understand the biomechanics of the human body in motor vehicle environments, physical models including anthropomorphic test devices (ATD) and biological models (postmortem human surrogates) are used, and sled tests are conducted. Deflection is often used as a biomechanical variable to characterize the effects of impact loading and derive injury criteria. The objective of the present study was to evaluate different techniques and recommend a methodology to determine the peak thorax and abdominal deflections from temporal contours using chestbands in oblique lateral impacts. The side impact ATD WorldSID representing human surrogates was positioned on a seat. The seat was rigidly fixed to the platform of an acceleration sled. The oblique load-wall fixed to the sled consisted of separate and adjustable plates to contact the shoulder, thorax, abdomen, and pelvis. Two 59-gage chestbands were wrapped on the thorax and abdomen. Tests were conducted at low, medium, and high velocities (3.4, 6.7, and 7.5m/s) and three methods, termed the spine-sternum, bilateral, and spine-box, were used to determine the global peak deflection and its angulation. Results indicated that all three methods produced very similar angulations, for all velocity tests, and at both thorax and abdominal regions. However, maximum deflections were the lowest in the spine-sternum, followed by bilateral and spine-box methods, with one exception. Based on the development of deflection contours, locations used in the definitions of the origin, and accuracy in identifying critical locations/points in time-varying contours, results of the present study indicate that the bilateral method is the optimum procedure to determine the oblique peak deflection vector in biomechanical tests. PMID:23357337

  9. Replacing 16 mm film cameras with high definition digital cameras

    SciTech Connect

    Balch, K.S.

    1995-12-31

    For many years 16 mm film cameras have been used in severe environments. These film cameras are used on Hy-G automotive sleds, airborne gun cameras, range tracking and other hazardous environments. The companies and government agencies using these cameras are in need of replacing them with a more cost effective solution. Film-based cameras still produce the best resolving capability, however, film development time, chemical disposal, recurring media cost, and faster digital analysis are factors influencing the desire for a 16 mm film camera replacement. This paper will describe a new camera from Kodak that has been designed to replace 16 mm high speed film cameras.

  10. Operational vibroseis system for long-distance traverses

    NASA Astrophysics Data System (ADS)

    Eisen, Olaf; Hofstede, Coen; Diez, Anja; Kristoffersen, Yngve; Lambrecht, Astrid; Mayer, Christoph; Blenkner, Rick; Hilmarsson, Sverrir

    2014-05-01

    This poster presents results and performance of an operational vibroseis system used in Antarctica on the Ekströmisen and its catchment area. The about 500 km long overland traverse covered very different surface regimes in the elevation range from sea level up to 1000 m in the austral season 2013/14. The presentation is the successful culmination of a six-year effort to develop an operational vibroseis system for Antarctica and Greenland. Over three weeks the campaign acquired: • 407 km of seismic profiles in total, thereof • 110 km in 6-fold resolution with 125 m shot spacing • 25 km in 3-fold resolution with 250 m shot spacing. The remaining distance was covered in single-fold with 750 m shot spacing. The traverse used a well-established 60 channel 1.5 km streamer and a new setup with a vibroseis Buggy "EnviroVibe" with Mattracks on a polyethylen sled. The sled had a hole in the center to lower the vibrator pad directly onto the snow surface. With this setup data production varied between 20 km/day for 6-fold and 40 km/day for single fold for a decent 9h day of measurements. The combination of Mattracks with the PE-sled was especially advantageous on hard and rough surfaces because of the flexibility of each and the relatively lose mounting by cargo straps and wooden blocks. Production speeds were limited by the snow streamer, which had an increasing damage rate of geophone groups for velocities above 6 km/h. The source system itself could easily accommodate transfer velocities of 15 km/h. In combination with the streamer winch mounted in front of the source on a separate freight sled the channel spacing could be reduced to fractions of the 25 m spacing interval by combining several sweeps at the same location, thus increasing spatial resolution. The vibrator source was operated with a 10-250 Hz sweep over 10 s with 80% of the peak force of 66 kN. On soft surfaces a setup-sweep was utilized. Preliminary data analysis shows that sea floor geomorphology

  11. 27. "SITE PLAN." Specifications No. OC15775, Drawing No. AF600915, sheet ...

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

    27. "SITE PLAN." Specifications No. OC1-57-75, Drawing No. AF-60-09-15, sheet 1 of 96, D.O. Series No. AF 1394/20, Rev. B. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 5296 Rev. B, Date: 11/17/59. Site plan of 20,000-foot track, including construction phasing notes. - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  12. The Effect of Obesity on the Restraint of Automobile Occupants

    PubMed Central

    Forman, Jason; Lopez-Valdes, Francisco J.; Lessley, David; Kindig, Matthew; Kent, Richard; Bostrom, Ola

    2009-01-01

    As obesity rates increase, the protection of obese occupants will become increasingly important in vehicle and restraint design. As a first step in this effort, this study seeks to compare the kinematics, dynamics, and injuries of obese post mortem human surrogates (PMHS) to (approximately) 50th percentile adult male PMHS in frontal impact sled tests with a force-limiting, pre-tensioning restraint system. Forty-eight km/h, frontal impact sled tests were performed with a sled buck representing the rear seat occupant compartment of a 2004 mid-sized sedan. The restraint system consisted of a 3-point belt with a pretensioner and a progressive force-limiter at the retractor. The test subjects were either obese PMHS or approximately 50th percentile adult male PMHS. Instrumentation included accelerometer packages on the spine. Deformation of the subjects' chests were measured using chestbands placed nominally at the superior-inferior locations of the 4th and 8th ribs. Tension in the restraint system was measured at the upper shoulder belt, lower shoulder belt, and the lap belt. Motion of the head, shoulder, pelvis, and knee were recorded using high-speed video. Two obese PMHS (average mass 137 kg, average stature 186 cm) and three approximately mid-sized male PMHS (average mass 68 kg, average stature 176 cm) were tested. The obese PMHS exhibited significantly greater forward motion of the head and the pelvis compared to the mid-sized PMHS. The obese PMHS also exhibited backwards torso rotation at the time of maximum forward excursion, whereas the mid-sized PMHS did not. The obese PMHS exhibited average maximum chest compressions of approximately 44% (± 9% standard deviation) of their initial chest depths, and exhibited 26 g (± 2 g) average 3 ms clip maximum chest resultant acceleration. In comparison, the mid-sized PMHS exhibited averages of 29% (± 9%) maximum chest compression and 35 g (± 4 g) maximum 3 ms clip chest acceleration. The obese PMHS exhibited 7 and 2 rib

  13. Fast energy and energy spectrum feedback in the SLC Linac

    SciTech Connect

    Abrams, G.S.; Soderstrom, E.; Seeman, J.T.; Campisi, I.E.; Herrmannsfeldt, W.; Lee, M.; Petersen, A.; Phinney, N.; Ross, M.; Thompson, K.

    1987-01-01

    The energies and energy spectra of the positron and electron beams emerging from the SLC Linac must be carefully maintained so that the beams can be transported through the Arcs to the Final Focus without phase space dilution and also to specify the collision energy. A fastback system has been designed and constructed to control these parameters. The energies and energy spectra are measured nondestructively using position monitors and synchrotron radiation width monitors. The controls consist of rf phases in the Damping Rings, SLED timing, and rf amplitude. Theoretical aspects of the feedback process, algorithms, and operational experience are discussed.

  14. Ultrawide-bandwidth, superluminescent light-emitting diodes using InAs quantum dots of tuned height.

    PubMed

    Haffouz, S; Barrios, P J; Normandin, R; Poitras, D; Lu, Z

    2012-03-15

    An ultrawide-bandwidth, superluminescent light-emitting diode (SLED) utilizing multiple layers of dots of tuned height is reported. Due to thermal effect, the superluminescent phenomenon is observed only under pulse-mode operation. The device exhibits a 3 dB bandwidth of 190 nm with central wavelength of 1020 nm under continuous-wave (cw) conditions. The maximum corresponding output power achieved in this device under cw and pulsed operation conditions are 0.54 mW and 17 mW, respectively. PMID:22446239

  15. The comparative analysis of various aerospace system concepts

    NASA Astrophysics Data System (ADS)

    Shkadov, L. M.; Denisov, V. Ye.; Lazarev, V. V.; Plokhikh, V. P.; Buzuluk, V. I.; Volodin, S. V.; Chervonenko, K. A.; Skipenko, V. V.

    1995-01-01

    Consideration is given to fully reusable winged two- and single-stage systems powered by hydrogen/oxygen rocket engines, which differ in types of takeoff [horizontal takeoff (HTO) using an undercarriage; ground sled-assisted takeoff; air launch from a subsonic carrier; and launching-pad vertical takeoff (VTO)]. The systems have been optimized and compared using two criteria: payload mass and "dry mass to payload mass" ratio. The influence of the gross weight of a system and the technological level on the criteria involved is being investigated.

  16. Replacing 16-mm film cameras with high-definition digital cameras

    NASA Astrophysics Data System (ADS)

    Balch, Kris S.

    1995-09-01

    For many years 16 mm film cameras have been used in severe environments. These film cameras are used on Hy-G automotive sleds, airborne gun cameras, range tracking and other hazardous environments. The companies and government agencies using these cameras are in need of replacing them with a more cost effective solution. Film-based cameras still produce the best resolving capability, however, film development time, chemical disposal, recurring media cost, and faster digital analysis are factors influencing the desire for a 16 mm film camera replacement. This paper will describe a new camera from Kodak that has been designed to replace 16 mm high speed film cameras.

  17. 29. "TEST TRACK, STATION '0' THROUGH '200' AREA." Specifications No. ...

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

    29. "TEST TRACK, STATION '0' THROUGH '200' AREA." Specifications No. ENG-OC-1-57-75, Drawing No. AF-6009-15, sheet 53 of 96, D.O. Series No. AF 1394/73, Rev. C. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 5296 Rev. C, Date: 19 NOV 59. Drawing includes plan, section, and details of track. - Edwards Air Force Base, South Base Sled Track, Edwards Air Force Base, North of Avenue B, between 100th & 140th Streets East, Lancaster, Los Angeles County, CA

  18. Designing for aircraft structural crashworthiness

    NASA Technical Reports Server (NTRS)

    Thomson, R. G.; Caiafa, C.

    1981-01-01

    This report describes structural aviation crash dynamics research activities being conducted on general aviation aircraft and transport aircraft. The report includes experimental and analytical correlations of load-limiting subfloor and seat configurations tested dynamically in vertical drop tests and in a horizontal sled deceleration facility. Computer predictions using a finite-element nonlinear computer program, DYCAST, of the acceleration time-histories of these innovative seat and subfloor structures are presented. Proposed application of these computer techniques, and the nonlinear lumped mass computer program KRASH, to transport aircraft crash dynamics is discussed. A proposed FAA full-scale crash test of a fully instrumented radio controlled transport airplane is also described.

  19. NASA general aviation crashworthiness seat development

    NASA Technical Reports Server (NTRS)

    Fasanella, E. L.; Alfaro-Bou, E.

    1979-01-01

    Three load limiting seat concepts for general aviation aircraft designed to lower the deceleration of the occupant in the event of a crash were sled tested and evaluated with reference to a standard seat. Dummy pelvis accelerations were reduced up to 50 percent with one of the concepts. Computer program MSOMLA (Modified Seat Occupant Model for Light Aircraft) was used to simulate the behavior of a dummy passenger in a NASA full-scale crash test of a twin engine light aircraft. A computer graphics package MANPLOT was developed to pictorially represent the occupant and seat motion.

  20. Pickup ions (E/O+/ greater than 55 keV) measured near Mars by Phobos-2 in February/March 1989

    NASA Astrophysics Data System (ADS)

    Kirsch, E.; Keppler, E.; Witte, M.; Rosenbauer, H.; Livi, S.; Schwingenschuh, K.; Afonin, V. V.; O'Sullivan, D.; Thompson, A.; McKenna-Lawlor, S.

    1991-11-01

    The Soviet spacecraft Phobos 2 reached Mars on January 29, 1989. The onboard SLED recorded particles of solar and planetary origin while in elliptical and circular orbits about the planet. Enhanced fluxes were identified, particularly during periods of spin stabilization, superimposed on the general particle intensity time profile. These latter fluxes are interpreted here, using backup evidence from simultaneous solar wind and magnetic field measurements recorded on the same spacecraft, to have constituted pickup ions (/O+/,/O2+/) with E/O+/ not less than 55 keV.

  1. Future ESA Missions in Biology

    NASA Astrophysics Data System (ADS)

    Bonting, Sjoerd L.

    1984-12-01

    A survey is given of the life sciences research program sponsored by the European Space Agency (ESA). This program rests on a number of facilities originated by ESA: Spacelab, Space sled, Biorack, Anthrorack, Eureca and its Botany — and Protein Crystallization facilities. They are all to be brough into space and returned by one of the NASA Space Shuttles. With these facilities a wide range of space biology research will be covered: cell biology, developmental biology, botany, human physiology, radio-biology, exobiology and biotechnology. Information is given on how to prepare, submit and execute an experiment proposal.

  2. Ireland's contribution to deep space missions

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, Susan M. P.

    1988-03-01

    Irish contributions to the Giotto mission, the Phobos mission, and the planned International Solar Terrestrial Physics (ISTP) program are discussed. Results are presented from the Energetic Particle Onset Admonitor (Epona) experiment, which flew on the Giotto mission. The Epona instruments detected electrons, protons, alpha particles, and pickup ions associated with Comet Halley. Other topics examined include the SLED experiment to study energetic-particle populations as part of the Phobos mission and expectations for Irish participation in the ISTP program, including the construction of a plasma and radio wave receiver.

  3. An overview of energetic particles (from 55 keV to > 30 MeV) recorded in the close Martian environment, and their energization in local and external processes

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, S.; Afonin, V. V.; Kirsch, E.; Schwingenschuh, K.; Slavin, J. A.; Trotignon, J. G.

    1998-01-01

    Observations made by the SLED particle detector on Phobos-2 in the close Martian environment from 29 January to 27 March, 1989 during the early rising phase of Solar Cycle 22, show the frequent presence close to the planet, under reasonably "quiet" interplanetary conditions, of particles with energies ( E) in the range from several tens of, to several hundred, keV. Under disturbed interplanetary circumstances, particles reaching energies of several tens of MeV were recorded close to Mars. Those particles in the keV range were observed at well-defined locations, i.e. at the Terminator Shocks ( E up to ≈600 keV); just inside the subsolar Planetopause ( E up to ≈225 keV), and travelling down the Tail, E≥55 keV. These three populations are herein suggested, instancing various candidate mechanisms, to have been energized by processes local to the planet. Since the seed particles for ions accelerated at the Terminator Shocks may comprise ambient, pre-accelerated, solar particles, the energies of ions detected by SLED during Bow Shock transits was observed (during two months) to vary between ≈50 keV and ≈600 keV. Particles with energies up to several tens of MeV which were found to suffuse the close planetary environment over extended periods, are interpreted to have been produced in association with solar processes external to Mars (Co-rotating Interaction Regions; Gradual and Impulsive Solar Events). Particle enhancements in the keV range recorded by SLED (under favourable magnetic conditions) during Bow Shock traversals, provide topographical information concerning the location of the Martian subsolar and distant shock surfaces. These observations constitute a new data set, complementary to those determinations of key boundaries derived from plasma and magnetic field measurements made aboard various American and Russian spacecraft at Mars which, for more than thirty years now, have been generally used in modelling the Solar Wind interaction with the planet

  4. View looks south southeast at North Base, from a point ...

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

    View looks south southeast at North Base, from a point near the rocket sled test track. From left to right, the most prominent buildings on the skyline are Building 4505 with its ancillary buildings; Building 4500, Control Tower; followed by Buildings 4402 (Hangar No. 2), 4401 (Hangar No. 1), and 4305 (Unicon Portable Hangar) with their respective ancillary structures. The large structure in the distance at the far right of the view is the Test Support Facility at South Base. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

  5. An Rf-gun-driven recirculated linac as injector and FEL driver.

    SciTech Connect

    Andersson, A.; Biedron, S.; Eriksson, M.; Freund, H.; Werin, S.

    1999-08-23

    A new pre-injector for the MAX-Laboratory is under design and construction. A thermionic rf gun, designed to operate at medium currents with low back bombardment power, is under construction. The gun will, via a magnetic compressor and energy filter, feed a recirculated linac consisting of two SLED-equipped structures giving 125 MeV each. The first will be delivered in 1999. The system is aimed as a pre-injector for the existing storage rings at MAX-Lab, but will also open up possibilities for a SASE FEL in the UV reaching above 100 MW below 100 run.

  6. Determination of the availability of appropriate aged flight rocket motors. [captive tests to determine case bond separation and grain bore cracking

    NASA Technical Reports Server (NTRS)

    Martin, P. J.

    1974-01-01

    A program to identify surplus solid rocket propellant engines which would be available for a program of functional integrity testing was conducted. The engines are classified as: (1) upper stage and apogee engines, (2) sounding rocket and launch vehicle engines, and (3) jato, sled, and tactical engines. Nearly all the engines were available because their age exceeds the warranted shelf life. The preference for testing included tests at nominal flight conditions, at design limits, and to establish margin limits. The principal failure modes of interest were case bond separation and grain bore cracking. Data concerning the identification and characteristics of each engine are tabulated. Methods for conducting the tests are described.

  7. Vehicle Interior Interactions and Kinematics of Rear Facing Child Restraints in Frontal Crashes

    PubMed Central

    Sherwood, C. P.; Gopalan, S.; Abdelilah, Y.; Marshall, R. J.; Crandall, J. R.

    2005-01-01

    The performance of rear facing child restraints in frontal crashes can be determined by controlling a) the child’s kinematics and b) interactions with vehicle structures. Twelve sled tests were performed to analyze the effect of the location and structural properties of vehicle interior components. The role of restraint kinematics was studied by developing computational models which underwent idealized motions. Stiff structures originally offset from the restraint, but which contact the restraint late in the test, cause increased injury values. Attachment methods which reduce child restraint rotation and more rigidly couple the restraint to the vehicle result in the best safety performance. PMID:16179150

  8. Easily constructed, economical seawater intake and supply system

    USGS Publications Warehouse

    Bouck, G.R.

    1981-01-01

    A water intake system was designed and installed in Admiralty Inlet, Puget Sound, Washington. The dual system consisted of polyvinylchloride (PVC) pipes, a concrete pit and pumps located on shore at zero tide; and cables attached laterally to the pipelines and terminally between a shoreward anchor and to a seaward intake sled held in place with an 1800 kg Dansforth anchor. The overall construction costs were much lower than those for concrete-lined ductile iron pipe. Nearly three years after its construction, this system has withstood tides and storms without apparent adverse effect. Its application to lakes or rivers is equally possible.

  9. The Inductrack concept: A new approach to magnetic levitation

    SciTech Connect

    Post, R.F.; Ryutov, D.

    1996-05-01

    This report describes theoretical and experimental investigations of a new approach to the problem of the magnetic levitation of a moving object. By contrast with previously studied levitation approaches, the Inductrack concept concept represents a simpler, potentially less expensive, and totally passive means of levitating a high-speed train. It may also be applicable to other areas where simpler magnetic levitation systems are needed, for example, high-speed test sleds for crash testing applications, or low-friction conveyer systems for industrial use.

  10. Polymer infiltration studies

    NASA Technical Reports Server (NTRS)

    Marchello, Joseph M.

    1994-01-01

    During the past three months, significant progress has been made on the preparation of carbon fiber composites using advanced polymer resins. The results are set forth in recent reports and publications, and will be presented at forthcoming national and international meetings. Current and ongoing research activities reported herein include: textile composites from powder-coated towpreg - role of surface coating in braiding; prepregger hot sled operation in making tape from powder coated tow; ribbonizing powder-impregnated towpreg; textile composites from powder-coated towpreg - role of bulk factor in consolidation; powder curtain prepreg process improvements in doctoring of powder; and hot/cold shoe for ATP open-section part warpage control.

  11. Assessment of the pubic force as a pelvic injury criterion in side impact.

    PubMed

    Leport, Tiphaine; Baudrit, Pascal; Trosseille, Xavier; Petit, Philippe; Palisson, Anna; Vallancien, Guy

    2007-10-01

    In the literature, injuries at the ischio or ilio pubic ramus level are reported to occur to approximately (3/4) of the occupants injured at the pelvis during side impact. Assuming that the load going through the pubis was a good indicator of the ramus stress, the pubic force was widely accepted as a protection criterion for pelvic fractures on side impact dummies. However, no data regarding the actual loads going through the pubis is currently available in the literature for Post Mortem Human Subjects (PMHS) in dynamic conditions. The goal of this study was to determine pelvic biofidelity specifications in terms of load path, to evaluate the pertinence of the pubic force as a criterion, and to develop a pelvic injury risk curve as a function of the pubic force. For that purpose, a pubic load cell was developed for PMHS use, and 16 side impact tests were performed on 8 PMHS using boundary conditions similar to impactor tests and sled tests reported in the literature. One kind of impact was applied on one side of a subject and the other kind of impact was then applied on the other side of the same subject, at non injury severities. The ratio between the peak external force and the peak pubic force was calculated for each subject, and a mean ratio was then calculated for each of the test conditions. These ratios were finally used to calculate the pubic forces from the external pelvic forces for 90 PMHS side impact test data available in the literature. Injury risk curves as a function of the pubic force were developed from these data. Two normalized pubic force corridors from the 16 tests are presented, the first one for the impactor tests, the second one for the sled-like tests. The test results show statistically different ratios between the peak external force and the peak pubic force, for the two configurations (an average ratio of 3.3 for impactor tests and 4.6 for sled-like tests). The PMHS injury risk curves based on the external pelvic force were observed to

  12. Construction of an unyielding target for large horizontal impacts.

    SciTech Connect

    Ammerman, Douglas James; Davie, Neil Thomas; Kalan, Robert J.

    2010-10-01

    Sandia National Laboratories has constructed an unyielding target at the end of its 2000-foot rocket sled track. This target is made up of approximately 5 million pounds of concrete, an embedded steel load spreading structure, and a steel armor plate face that varies from 10 inches thick at the center to 4 inches thick at the left and right edges. The target/track combination will allow horizontal impacts at regulatory speeds of very large objects, such as a full-scale rail cask, or high-speed impacts of smaller packages. The load-spreading mechanism in the target is based upon the proven design that has been in use for over 20 years at Sandia's aerial cable facility. That target, with a weight of 2 million pounds, has successfully withstood impact forces of up to 25 million pounds. It is expected that the new target will be capable of withstanding impact forces of more than 70 million pounds. During construction various instrumentation was placed in the target so that the response of the target during severe impacts can be monitored. This paper will discuss the construction of the target and provide insights on the testing capabilities at the sled track with this new target.

  13. Unicompartmental knee prostheses: in vitro wear assessment of the menisci tibial insert after two different fixation methods

    NASA Astrophysics Data System (ADS)

    Affatato, S.; Spinelli, M.; Zavalloni, M.; Carmignato, S.; Lopomo, N.; Marcacci, M.; Viceconti, M.

    2008-10-01

    Knee osteoarthritis is a complex clinical scenario where many biological and mechanical factors influence the severity of articular degenerative changes. Minimally invasive knee prosthetic surgery, with only a compartment replacement (unicompartmental knee replacement), might be a good compromise between osteotomy and total knee prosthesis. The focus of this study was to develop and validate a protocol to assess the fixation method of the femoral components in mechanical simulation, for pre-clinical validation; the wear behaviour of two different fixation frames was quantified and compared. In particular, two different wear tests were conducted using the same knee simulator, the same load profiles and the same kinematics; two different fixation methods were applied to the femoral sleds (synthetic femur and metal block). Surface characterization on both articulating bearings was performed by a roughness measuring machine and coordinate measuring machine. The wear produced by the tibial inserts using the synthetic femur was considerably higher than the wear registered by the metal-block holder. Roughness measurements on femoral sleds showed a limited number of scratches with high Rt values for the metal-block set-up; the damaged surface broadened in the case of femoral condyles and tibial inserts mounted on composite bone, but lower Rt and linear penetration values were measured. The two holding frames showed different wear activities as a consequence of dissimilar dynamic performance. Further observations should be made in vivo to prove the actual importance of synthetic bone simulations and specific material behaviour.

  14. First identification in energetic particles of characteristic plasma boundaries at Mars and an account of various energetic particle populations close to the planet

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, S. M. P.; Afonin, V.; Yeroshenko, Ye.; Keppler, E.; Kirsch, E.; Schwingenschuh, K.

    1993-05-01

    Signatures of characteristic boundaries, interpreted to be the bow shock and magnetopause with, between them, the magnetosheath, were recorded for the first time in energetic particles (between 30 keV and 3.2 MeV) in the downstream nightside Martian environment by the SLED instrument aboard Phobos 2. Also, energetic particles, interpreted to be oxygen ions, were recorded by SLED at four distinct locations close to Mars. These include (a) anisotropic fluxes at the terminator shocks with energies of up to at least 72 keV; (b) anisotropic fluxes with energies of up to at least 225 keV inside the magnetopause, at a height above the planet of approximately 900 km in the subsolar part of the magnetosphere; (c) fluxes with energies of up to at least 3.2 MeV in the flanks of the magnetosheath displaying quasi-periodic variations (period approximately 45 min) which are synchronous across the recorded energy spectrum and correlated in time with changes in the local magnetic field; and (d) beams of oxygen ions with energies of up to at least 55 keV traveling out along open field lines in the magnetotail with, in some cases, a suggestion of confinement close to the neutral sheet. A preliminary discussion is provided concerning the energization of the various populations of particles identified.

  15. Wheelchair caster loading during frontal impact.

    PubMed

    Bertocci, Gina E; van Roosmalen, Linda

    2003-01-01

    Many wheelchair users are required or choose to use their wheelchairs as a motor vehicle seat during transport. It is therefore key that the wheelchair components be designed to tolerate crash-level loading conditions. Casters are particularly prone to failure under crash loading conditions. Our study evaluated wheelchair caster loading during 20g/48 kph frontal sled impact testing using an 85-kg surrogate wheelchair base (SWCB) with casters positioned on a load-measuring platform. A Hybrid III 50th percentile male test dummy was seated in the SWCB, which simulated a power wheelchair and was secured using four-point tiedowns. Various rear securement point heights and wheelchair seating systems were used to study their effect on caster loading. Caster normal loading was found to vary from 769 to 7,209 N depending on rear securement location and integrity of the seating system. Dynamic sled impact test results showed that normal loading of the front wheelchair casters was influenced by wheelchair seating system integrity and rear wheelchair securement height. Shear loading varied from 781 to 1,589 N and did not appear to be dependent on seat integrity or rear securement height. The load/time histories measured during dynamic impact testing can be used to guide the development of transit-safe caster design. PMID:15137727

  16. Adaptation of the phase of the human linear vestibulo-ocular reflex (LVOR) and effects on the oculomotor neural integrator

    NASA Technical Reports Server (NTRS)

    Hegemann, S.; Shelhamer, M.; Kramer, P. D.; Zee, D. S.

    2000-01-01

    The phase of the translational linear VOR (LVOR) can be adaptively modified by exposure to a visual-vestibular mismatch. We extend here our earlier work on LVOR phase adaptation, and discuss the role of the oculomotor neural integrator. Ten subjects were oscillated laterally at 0.5 Hz, 0.3 g peak acceleration, while sitting upright on a linear sled. LVOR was assessed before and after adaptation with subjects tracking the remembered location of a target at 1 m in the dark. Phase and gain were measured by fitting sine waves to the desaccaded eye movements, and comparing sled and eye position. To adapt LVOR phase, the subject viewed a computer-generated stereoscopic visual display, at a virtual distance of 1 m, that moved so as to require either a phase lead or a phase lag of 53 deg. Adaptation lasted 20 min, during which subjects were oscillated at 0.5 Hz/0.3 g. Four of five subjects produced an adaptive change in the lag condition (range 4-45 deg), and each of five produced a change in the lead condition (range 19-56 deg), as requested. Changes in drift on eccentric gaze suggest that the oculomotor velocity-to-position integrator may be involved in the phase changes.

  17. Computing body segment trajectories in the Hybrid III dummy using linear accelerometer data.

    PubMed

    Shea, R T; Viano, D C

    1994-02-01

    An analytical method was developed and tested using several mini-sled and Hyge sled tests to calculate the planar trajectory of a Hybrid III dummy head. Aimed at expediting the Hybrid III test analyses, it may provide an opportunity for cost savings through reduced hardware and manpower on film analyses. Transformation from the moving coordinate to the laboratory coordinate is based on the angular positions integrated from the derived angular accelerations. Gravitational correction of the linear accelerometers was found to be insignificant. The computed head trajectories were compared to the ones obtained from the high speed film images. Accuracy of the calculated head trajectory relies heavily on the accuracy of the computed angular acceleration. Strain-gaged accelerometers are not dependable at all times during an impact and an ill-behaved signal for a very short period may create a significant drift in computed displacement due to double integrations. Accuracy of the currently available accelerometers is not high enough for an angular displacement calculation. A new generation of accelerometers with higher accuracy, or an angular velocity sensor may provide more accurate angular displacement for trajectory analyses. The redundancy of the in-line accelerations helps improve the isolation of erroneous outputs and improve accuracy of the procedure. PMID:8189712

  18. Spatial and temporal variation in the abundance, distribution and population structure of epibenthic megafauna in Port Foster, Deception Island

    NASA Astrophysics Data System (ADS)

    Cranmer, T. L.; Ruhl, H. A.; Baldwin, R. J.; Kaufmann, R. S.

    2003-06-01

    Abundance and spatial distribution of epibenthic megafauna were examined at Port Foster, Deception Island, five times between March 1999 and November 2000. Camera sled surveys and bottom trawls were used to identify and collect specimens, and camera sled photographs also were used to determine abundances and spatial distributions for each species. The ophiuroid Ophionotus victoriae, the regular echinoid Sterechinus neumayeri, and one or more species of Porifera were the most abundant taxa during this sampling period. Abundances of O. victoriae varied throughout the annual cycle, peaking in June 2000, and were correlated positively with sedimentation rates. In contrast, abundances of S. neumayeri were consistent throughout the sampling period, except for a peak in June 2000, during austral winter. Peak abundances for both species coincided with a large number of small individuals, indicating apparent recruitment events for O. victoriae and S. neumayeri during this time period. Poriferans, as a group, had statistically similar abundances during each sampling period. Low-abundance species tended to be aggregated on both small and large spatial scales, their distributions probably influenced by reproductive method, gregarious settlement, and food availability. The spatial distribution of S. neumayeri in June 2000 and O. victoriae was random across multiple spatial scales, perhaps in response to food availability and broad environmental tolerances, respectively.

  19. Upper and Lower Neck Loads in Belted Human Surrogates in Frontal Impacts

    PubMed Central

    Yoganandan, Narayan; Pintar, Frank A.; Moore, Jason; Rinaldi, James; Schlick, Michael; Maiman, Dennis J.

    2012-01-01

    The upper and lower neck loads in the restrained Hybrid III dummy and Test Device for Human Occupant Restraint (THOR) were computed in simulated frontal impact sled tests at low, medium, and high velocities; repeatability performance of the two dummies were evaluated at all energy inputs; peak forces and moments were compared with computed loads at the occipital condyles and cervical-thoracic junctions from tests using post mortem human surrogates (PMHS). A custom sled buck was used to position the surrogates. Repeated tests were conducted at each velocity for each dummy and sufficient time was allowed to elapse between the two experiments. The upper and lower neck forces and moments were determined from load cell measures and its locations with respect to the ends of the neck. Both dummies showed good repeatability for axial and shear forces and bending moments at all changes in velocity inputs. Morphological characteristics in the neck loading responses were similar in all surrogates, although the peak magnitudes of the variables differed. In general, the THOR better mimicked the PMHS response than the Hybrid III dummy, and factors such as neck design and chest compliance were attributed to the observed variations. While both dummies were not designed for use at the two extremes of the tested velocities, results from the present study indicate that, currently the THOR may be the preferred anthropomorphic testing device in crashworthiness research studies and full-scale vehicle tests at all velocities. PMID:23169123

  20. Upper and lower neck loads in belted human surrogates in frontal impacts.

    PubMed

    Yoganandan, Narayan; Pintar, Frank A; Moore, Jason; Rinaldi, James; Schlick, Michael; Maiman, Dennis J

    2012-01-01

    The upper and lower neck loads in the restrained Hybrid III dummy and Test Device for Human Occupant Restraint (THOR) were computed in simulated frontal impact sled tests at low, medium, and high velocities; repeatability performance of the two dummies were evaluated at all energy inputs; peak forces and moments were compared with computed loads at the occipital condyles and cervical-thoracic junctions from tests using post mortem human surrogates (PMHS). A custom sled buck was used to position the surrogates. Repeated tests were conducted at each velocity for each dummy and sufficient time was allowed to elapse between the two experiments. The upper and lower neck forces and moments were determined from load cell measures and its locations with respect to the ends of the neck. Both dummies showed good repeatability for axial and shear forces and bending moments at all changes in velocity inputs. Morphological characteristics in the neck loading responses were similar in all surrogates, although the peak magnitudes of the variables differed. In general, the THOR better mimicked the PMHS response than the Hybrid III dummy, and factors such as neck design and chest compliance were attributed to the observed variations. While both dummies were not designed for use at the two extremes of the tested velocities, results from the present study indicate that, currently the THOR may be the preferred anthropomorphic testing device in crashworthiness research studies and full-scale vehicle tests at all velocities. PMID:23169123

  1. Towards a Natural Theory of Dark Energy: Supersymmetric Large Extra Dimensions

    SciTech Connect

    Burgess, C.P.

    2004-12-10

    The first part of this article summarizes the evidence for Dark Energy and Dark Matter, as well as the naturalness issues which plague current theories of Dark Energy. The main point of this part is to argue why these naturalness issues should provide the central theoretical guidance for the search for a successful theory. The second part of the article describes the present status of what I regard as being the best mechanism yet proposed for addressing this issue: Six-dimensional Supergravity with submillimetre-sized Extra Dimensions (Supersymmetric Large Extra Dimensions, or SLED for short). Besides summarizing the SLED proposal itself, this section also describes the tests which this model has passed, the main criticisms which have been raised, and the remaining challenges which remain to be checked. The bottom line is that the proposal survives the tests which have been completed to date, and predicts several distinctive experimental signatures for cosmology, tests of gravity and for accelerator-based particle physics.

  2. Evaluation of chest injury mechanisms in nearside oblique frontal impacts.

    PubMed

    Iraeus, Johan; Lindquist, Mats; Wistrand, Sofie; Sibgård, Elin; Pipkorn, Bengt

    2013-01-01

    Despite the use of seat belts and modern safety systems, many automobile occupants are still seriously injured or killed in car crashes. Common configurations in these crashes are oblique and small overlap frontal impacts that often lead to chest injuries.To evaluate the injury mechanism in these oblique impacts, an investigation was carried out using mathematical human body model simulations. A model of a simplified vehicle interior was developed and validated by means of mechanical sled tests with the Hybrid III dummy. The interior model was then combined with the human body model THUMS and validated by means of mechanical PMHS sled tests. Occupant kinematics as well as rib fracture patterns were predicted with reasonable accuracy.The final model was updated to conform to modern cars and a simulation matrix was run. In this matrix the boundary conditions, ΔV and PDOF, were varied and rib fracture risk as a function of the boundary conditions was evaluated using a statistical framework.In oblique frontal impacts, two injury producing mechanisms were found; (i) diagonal belt load and (ii) side structure impact. The second injury mechanism was found for PDOFs of 25°-35°, depending on ΔV. This means that for larger PDOFs, less ΔV is needed to cause a serious chest injury. PMID:24406957

  3. Evaluation of Chest Injury Mechanisms in Nearside Oblique Frontal Impacts

    PubMed Central

    Iraeus, Johan; Lindquist, Mats; Wistrand, Sofie; Sibgård, Elin; Pipkorn, Bengt

    2013-01-01

    Despite the use of seat belts and modern safety systems, many automobile occupants are still seriously injured or killed in car crashes. Common configurations in these crashes are oblique and small overlap frontal impacts that often lead to chest injuries. To evaluate the injury mechanism in these oblique impacts, an investigation was carried out using mathematical human body model simulations. A model of a simplified vehicle interior was developed and validated by means of mechanical sled tests with the Hybrid III dummy. The interior model was then combined with the human body model THUMS and validated by means of mechanical PMHS sled tests. Occupant kinematics as well as rib fracture patterns were predicted with reasonable accuracy. The final model was updated to conform to modern cars and a simulation matrix was run. In this matrix the boundary conditions, ΔV and PDOF, were varied and rib fracture risk as a function of the boundary conditions was evaluated using a statistical framework. In oblique frontal impacts, two injury producing mechanisms were found; (i) diagonal belt load and (ii) side structure impact. The second injury mechanism was found for PDOFs of 25°–35°, depending on ΔV. This means that for larger PDOFs, less ΔV is needed to cause a serious chest injury. PMID:24406957

  4. M.I.T./Canadian vestibular experiments on the Spacelab-1 mission: 6. Vestibular reactions to lateral acceleration following ten days of weightlessness

    NASA Technical Reports Server (NTRS)

    Arrott, A. P.; Young, L. R.

    1986-01-01

    Tests of otolith function were performed pre-flight and post-flight on the science crew of the first Spacelab Mission with a rail-mounted linear acceleration sled. Four tests were performed using horizontal lateral (y-axis) acceleration: perception of linear motion, a closed loop nulling task, dynamic ocular torsion, and lateral eye deviations. The motion perception test measured the time to detect the onset and direction of near threshold accelerations. Post-flight measures of threshold and velocity constant obtained during the days immediately following the mission showed no consistent pattern of change among the four crewmen compared to their pre-flight baseline other than an increased variability of response. In the closed loop nulling task, crewmen controlled the motion of the sled and attempted to null a computer-generated random disturbance motion. When performed in the light, no difference in ability was noted between pre-flight and post-flight. In the dark, however, two of the four crewmen exhibited somewhat enhanced performance post-flight. Dynamic ocular torsion was measured in response to sinusoidal lateral acceleration which produces a gravitionertial stimulus equivalent to lateral head tilt without rotational movement of the head. Results available for two crewmen suggest a decreased amplitude of sinusoidal ocular torsion when measured on the day of landing (R+0) and an increasing amplitude when measured during the week following the mission.

  5. OT1_rmeijeri_1: Gas excitation through black hole accretion and star formation in the centers of active galaxies.

    NASA Astrophysics Data System (ADS)

    Meijerink, R.

    2010-07-01

    Stunning observations with SPIRE FTS of Mrk 231 have shown that CO lines are very bright up to J=13-12, and there is no sign of a decline in the CO Spectral Line Energy Distribution (SLED). Our SPIRE FTS spectra show that this is a common feature of AGN type galaxies. Therefore, we propose to observe a set of 4 very high-J CO line transitions using the PACS spectrometer, for 5 of these well studied proto-typical (Ultra-)Luminous Infrared Galaxies ((U)LIRGs) and one starburst galaxy. The question of the relative role and contribution of AGN to the far-infrared luminosities of local (U)LIRG systems has long been a problem in our understanding of the evolutionary path of these objects, and as well for the interpretation of deep far-infrared surveys. Our SPIRE FTS and our ground-based CO line observations together with the PACS observations in this program will allow us, for the first time, to complete a full CO SLED for a set of (U)LIRGs. Combining this with our models of Photon Dominated Regions (PDRs) and X-ray Dominated Regions (XDRs), we will then be able to determine the physical state of the interstellar medium and estimate the starburst/AGN contribution to the total energetics of these systems.

  6. Co Spectral Line Energy Distributions in Orion Sources: Templates for Extragalactic Observations

    NASA Astrophysics Data System (ADS)

    Indriolo, Nick; Bergin, Edwin

    2015-06-01

    The Herschel Space Observatory has enabled the observation of CO emission lines originating in the J=5 through J=48 rotational levels. Surveys of active galaxies (e.g., starbursts, Seyferts, ULIRGs) detect emission from levels as high as J=30, but the precise excitation mechanisms responsible for producing the observed CO SLEDs (Spectral Line Energy Distribution) remain ambiguous. To better constrain the possible excitation mechanisms in extragalactic sources, we investigate the CO SLEDs arising from sources with known characteristics in the nearby Orion region. Targets include Orion-KL (high-mass star forming region containing a hot core, embedded protostars, outflows, and shocks), Orion South (high-mass star forming region containing embedded protostars, outflows, and a photodissociation region), Orion H_2 Peak 1 (molecular shock), and the Orion Bar (a photodissociation region). Emission lines from complex sources are decomposed using velocity information from high spectral resolution observations made with Herschel-HIFI (Heterodyne Instrument for the Far-Infrared). Each source and/or component is taken as a template for a particular excitation mechanism, and then applied to interpret excitation in more distant regions within the Galaxy, as well as external galaxies.

  7. Towards a Natural Theory of Dark Energy: Supersymmetric Large Extra Dimensions

    NASA Astrophysics Data System (ADS)

    Burgess, C. P.

    2004-12-01

    The first part of this article summarizes the evidence for Dark Energy and Dark Matter, as well as the naturalness issues which plague current theories of Dark Energy. The main point of this part is to argue why these naturalness issues should provide the central theoretical guidance for the search for a successful theory. The second part of the article describes the present status of what I regard as being the best mechanism yet proposed for addressing this issue: Six-dimensional Supergravity with submillimetre-sized Extra Dimensions (Supersymmetric Large Extra Dimensions, or SLED for short). Besides summarizing the SLED proposal itself, this section also describes the tests which this model has passed, the main criticisms which have been raised, and the remaining challenges which remain to be checked. The bottom line is that the proposal survives the tests which have been completed to date, and predicts several distinctive experimental signatures for cosmology, tests of gravity and for accelerator-based particle physics.

  8. Modelling the Sub-mm Emission of Galaxies Over Cosmic Time

    NASA Astrophysics Data System (ADS)

    Popping, G.; Pérez-Beaupuits, J. P.

    2015-12-01

    At redshift z˜ 1-3 the star-formation rate density (SFRD) of the Universe reached its peak, after which it dropped towards its current day value. ALMA allows us to observe atoms and molecules like C, C+, [OI], CO, and HCN for large groups of star- forming (SF) galaxies during this cosmic epoch. Emission lines from these species are good tracers of the properties of the interstellar medium (ISM) out of which new stars form. This proceeding describes our efforts to model the sub-mm line emission of these elements in SF galaxies, using the combination of a semi-analytic model of galaxy formation and a radiative transfer code. The presented model successfully reproduces CO scaling relations for local and high-redshift galaxies. Here we use this model to make predictions for the CO Spectral Line Energy Distribution (CO SLED) of galaxies at redshift z=0.0, z=1.2, and z=2.0. We discuss what physical processes drive the change in CO SLED shape with redshift and discuss future strategies to observe this.

  9. Magnetic shadowing of high energy ions at Mars and how this effect can be simulated using a hybrid model

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, S.; Kallio, E.; Jarvinen, R.; Afonin, V. V.

    2012-02-01

    Energetic particle data recorded by the SLED instrument aboard Phobos-2 while in circular orbit about Mars (6-26 March, 1989) showed the presence of magnetic shadowing. A 3-D, self consistent, hybrid model (HYB-Mars) supplemented by test particle simulations was developed to study the response of the Martian plasma environment to solar disturbances and to reproduce, in particular, the magnetic shadowing effect. The pertaining magnetic and electric fields as well as the properties of high energy ions present at Mars under conditions of extreme solar disturbances, can be derived from HYB-Mars. This model predicted a plasma phenomenon at the planet, named here `solar wind-flow shadowing', which was earlier identified in the measurements of the ASPERA (plasma) experiment aboard Phobos-2. HYB also predicted magnetic shadowing which is qualitatively similar to that recorded by SLED. The simulations suggest that the configuration of a magnetic shadow depends on the pertaining solar wind density and velocity, and on the magnitude and direction of the interplanetary magnetic field. It is currently planned to input to the HYB model plasma and magnetic field data measured contemporaneously with the particle measurements aboard Phobos-2 so as to more realistically match the simulated results with the in situ observations.

  10. CO Spectral Line Energy Distributions in Orion Sources: Templates for Extragalactic Observations

    NASA Astrophysics Data System (ADS)

    Indriolo, Nick; Bergin, Edwin A.; Goicoechea, Javier; Schilke, Peter

    2016-01-01

    Relative populations in the excited rotational levels of CO are sensitive to conditions in the interstellar medium. Emission lines originating in these levels can thus be used in constraining parameters such as density, temperature, and radiation field. The Herschel Space Observatory has enabled the observation of CO emission lines arising from the J=4 through J=48 rotational levels, many of which are detected in different sources within the Orion star-forming region. We present observations of CO emission toward Orion KL, Orion H2 Peak 1, Orion South, and the Orion Bar, all of which show distinctive CO spectral line energy distributions (SLEDs) indicating the different excitation mechanisms at work. Using the high spectral resolution HIFI observations, we decompose emission line profiles into multiple components (e.g., shock, outflow, photodissociation region, ambient cloud) in order to characterize the CO SLED associated with each component. In doing so, we generate templates for the various excitation mechanisms that can be applied toward understanding the processes occurring in unresolved star-forming regions where CO observations have been made.

  11. Abundant box jellyfish, Chironex sp. (Cnidaria: Cubozoa: Chirodropidae), discovered at depths of over 50 m on western Australian coastal reefs

    PubMed Central

    Keesing, John K.; Strzelecki, Joanna; Stowar, Marcus; Wakeford, Mary; Miller, Karen J.; Gershwin, Lisa-Ann; Liu, Dongyan

    2016-01-01

    Box jellyfish cause human fatalities and have a life cycle and habit associated with shallow waters (<5 m) in mangrove creeks, coastal beaches, embayments. In north-western Australia, tow video and epibenthic sled surveys discovered large numbers (64 in a 1500 m tow or 0.05 m−2) of Chironex sp. very near to the benthos (<50 cm) at depths of 39–56 m. This is the first record of a population of box jellyfish closely associated with the benthos at such depths. Chironex were not widespread, occurring only in 2 of 33 tow videos and 3 of 41 epibenthic sleds spread over 2000 km2. All Chironex filmed or captured were on low to medium relief reefs with rich filter feeder communities. None were on soft sediment habitat despite these habitats comprising 49% of all sites. The importance of the reef habitat to Chironex remains unclear. Being associated with filter feeder communities might represent a hazard, and other studies have shown C. fleckeri avoid habitats which represent a risk of entanglement of their tentacles. Most of our observations were made during the period of lowest tidal current flow in the morning. This may represent a period favourable for active hunting for prey close to the seabed. PMID:26924604

  12. A rapid method to characterize seabed habitats and associated macro-organisms

    USGS Publications Warehouse

    Anderson, T.J.; Cochrane, G.R.; Roberts, D.A.; Chezar, H.; Hatcher, G.

    2007-01-01

    This study presents a method for rapidly collecting, processing, and interrogating real-time abiotic and biotic seabed data to determine seabed habitat classifications. This is done from data collected over a large area of an acoustically derived seabed map, along multidirectional transects, using a towed small camera-sled. The seabed, within the newly designated Point Harris Marine Reserve on the northern coast of San Miguel Island, California, was acoustically imaged using sidescan sonar then ground-truthed using a towed small camera-sled. Seabed characterizations were made from video observations, and were logged to a laptop computer (PC) in real time. To ground-truth the acoustic mosaic, and to characterize abiotic and biotic aspects of the seabed, a three-tiered characterization scheme was employed that described the substratum type, physical structure (i.e., bedform or vertical relief), and the occurrence of benthic macrofauna and flora. A crucial advantage of the method described here, is that preliminary seabed characterizations can be interrogated and mapped over the sidescan mosaic and other seabed information within hours of data collection. This ability to rapidly process seabed data is invaluable to scientists and managers, particularly in modifying concurrent or planning subsequent surveys.

  13. Corrosion of Uranium in Desert Soil, with Application to GCD Source Term M

    SciTech Connect

    ANDERSON, HOWARD L.; BACA, JULIANNE; KRUMHANSL, JAMES L.; STOCKMAN, HARLAN W.; THOMPSON, MOLLIE E.

    1999-09-01

    Uranium fragments from the Sandia Sled Track were studied as analogues for weapons components and depleted uranium buried at the Greater Confinement Disposal (GCD) site in Nevada. The Sled Track uranium fragments originated as weapons mockups and counterweights impacted on concrete and soil barriers, and experienced heating and fragmentation similar to processes thought to affect the Nuclear Weapons Accident Residues (NWAR) at GCD. Furthermore, the Sandia uranium was buried in unsaturated desert soils for 10 to 40 years, and has undergone weathering processes expected to affect the GCD wastes. Scanning electron microscopy, X-ray diffraction and microprobe analyses of the fragments show rapid alteration from metals to dominantly VI-valent oxy-hydroxides. Leaching studies of the samples give results consistent with published U-oxide dissolution rates, and suggest longer experimental periods (ca. 1 year) would be required to reach equilibrium solution concentrations. Thermochemical modeling with the EQ3/6 code indicates that the uranium concentrations in solutions saturated with becquerelite could increase as the pore waters evaporate, due to changes in carbonate equilibria and increased ionic strength.

  14. Abundant box jellyfish, Chironex sp. (Cnidaria: Cubozoa: Chirodropidae), discovered at depths of over 50 m on western Australian coastal reefs.

    PubMed

    Keesing, John K; Strzelecki, Joanna; Stowar, Marcus; Wakeford, Mary; Miller, Karen J; Gershwin, Lisa-Ann; Liu, Dongyan

    2016-01-01

    Box jellyfish cause human fatalities and have a life cycle and habit associated with shallow waters (<5 m) in mangrove creeks, coastal beaches, embayments. In north-western Australia, tow video and epibenthic sled surveys discovered large numbers (64 in a 1500 m tow or 0.05 m(-2)) of Chironex sp. very near to the benthos (<50 cm) at depths of 39-56 m. This is the first record of a population of box jellyfish closely associated with the benthos at such depths. Chironex were not widespread, occurring only in 2 of 33 tow videos and 3 of 41 epibenthic sleds spread over 2000 km(2). All Chironex filmed or captured were on low to medium relief reefs with rich filter feeder communities. None were on soft sediment habitat despite these habitats comprising 49% of all sites. The importance of the reef habitat to Chironex remains unclear. Being associated with filter feeder communities might represent a hazard, and other studies have shown C. fleckeri avoid habitats which represent a risk of entanglement of their tentacles. Most of our observations were made during the period of lowest tidal current flow in the morning. This may represent a period favourable for active hunting for prey close to the seabed. PMID:26924604

  15. Preliminary Design of a Ramjet for Integration with Ground-Based Launch Assist

    NASA Technical Reports Server (NTRS)

    Sayles, Emily L.

    2008-01-01

    This viewgraph presentation reviews the preliminary design of a ramjet for integration with a ground based launch assist. The reasons for the use of ground-based launch assist and the proposed mechanism for a system are reviewed. The use of a Optimal Trajectory by Implicit Simulation (OTIS), to model the flight and comparison with an actual rocket trajectory is given. The OTIS system is reviewed, The benefits of a launch assist system are analyzed concluding that a launch assist can provide supersonic speeds thus allowing ignition of ramjet without an onboard compressor. This means a further reduction in total launch weight. The Ramjet study is reviewed next. This included a review of the ONX simulations, the verification of the ONX results with the use of Holloman Sled experiment data as derived from the Feasibility of Ramjet Engine Test Capability on The Holloman AFB Sled Track. The conclusion was that the ONX system was not sufficient to meet the needs for the modeling required. The GECAT (Graphical Engine Cycle Analysis Tool) is examined. The results of the GECAT simulations was verified with data from Stataltex and D21 flights. The Next steps are: to create a GECAT Model of a launch assist ramjet, to adjust the geometry to produce the desired thrust, and to survey the ramjet's performance over a range of Mach numbers. The assumptions and requirements of a launch assist ramjet are given, and the acceptable flight regimes are reviewed.

  16. Near-shore sand thickness and stratigraphy mapping with a submerged GPR antenna system; southeast Lake Michigan

    SciTech Connect

    Sauck, W.A.; Seng, D.L. )

    1994-04-01

    Twenty-one shore perpendicular profiles, spaced at nominal 5 km intervals, have been surveyed with a bottom-sled mounted Ground Penetrating Radar (GPR) antenna system between Benton Harbor, MI, and Gary, IN. Either a commercial 500 MHz or a custom 145 MHz antenna were used. The bottom sled also carried an upward looking SONAR transducer to give concurrent water depth, and was towed from the beach out to water depths of 6 meters or more, usually ending about 500 meters from shore. Bedding structures and details are clearly visible on the GPR sections within the sand bars and sand blankets. Bottom morphology and the nature of the sand bodies change markedly from the NE to the SW limits of the survey area. At the NE profiles there are multiple, pronounced (or high amplitude) offshore bars, with the substrate (glacial clay, shale, or silty sand) exposed or nearly exposed between bars. Internal structure is generally foreset or cross bedding in the bars. Sand was thin or missing immediately to the Sw of several other jetty structures in addition to the one at St. Joseph. In general the sand bars became much less pronounced to the SW, and internal structures were dominated by parallel bedding and subtle angular unconformities. Near St. Joseph, the exposed substrate is almost certainly being eroded, even to water depths as great as 6 meters. Thus, the equilibrium bottom profile continues to deepen shoreward, causing the continued threat of bluff erosion in spite of annual beach nourishment efforts at this site.

  17. ER Consolidated Qtrly Rpt_July-September 2015_January 2016

    SciTech Connect

    Cochran, John R.

    2016-01-01

    This Environmental Restoration Operations (ER) Consolidated Quarterly Report (ER Quarterly Report) provides the status of ongoing corrective action activities being implemented by Sandia National Laboratories, New Mexico (SNL/NM) for the July, August, and September 2015 quarterly reporting period. The Solid Waste Management Units (SWMUs) and Areas of Concern (AOCs) identified for corrective action at SNL/NM are listed in Table I-1. The work completed during this quarter is reported below in Sections I.2.1 and I.2.2. Section I.2.1 summarizes the quarterly activities at sites undergoing corrective action field activities (SWMUs 8 and 58, 68, 149, 154, and 502, and three groundwater AOCs). Section I.2.2 summarizes quarterly activities at sites where the New Mexico Environment Department (NMED) has issued a certificate of completion and the site is in the corrective action complete (CAC) regulatory process. Currently, the Mixed Waste Landfill (MWL, SWMU 76) is the only site in the CAC regulatory process. Corrective action activities have been deferred at the Long Sled Track (SWMU 83), the Gun Facilities (SWMU 84), and the Short Sled Track (SWMU 240) because these are active mission facilities.

  18. Motion perception during tilt and translation after space flight

    NASA Astrophysics Data System (ADS)

    Clément, Gilles; Wood, Scott J.

    2013-11-01

    Preliminary results of an ongoing study examining the effects of space flight on astronauts' motion perception induced by independent tilt and translation motions are presented. This experiment used a sled and a variable radius centrifuge that translated the subjects forward-backward or laterally, and simultaneously tilted them in pitch or roll, respectively. Tests were performed on the ground prior to and immediately after landing. The astronauts were asked to report about their perceived motion in response to different combinations of body tilt and translation in darkness. Their ability to manually control their own orientation was also evaluated using a joystick with which they nulled out the perceived tilt while the sled and centrifuge were in motion. Preliminary results confirm that the magnitude of perceived tilt increased during static tilt in roll after space flight. A deterioration in the crewmember to control tilt using non-visual inertial cues was also observed post-flight. However, the use of a tactile prosthesis indicating the direction of down on the subject's trunk improved manual control performance both before and after space flight.

  19. Study of cervical muscle response and injury of driver during a frontal vehicle collision.

    PubMed

    Gao, Zhenhai; Li, Chuzhao; Hu, Hongyu; Zhao, Hui; Chen, Chaoyang; Yu, Huili

    2015-01-01

    Frontal vehicle collisions can cause injury to a driver's cervical muscles resulting from intense changes in muscle strain and muscle load. This study investigated the influence of collision forces in a sled test environment using a modified Hybrid III 50th percentile dummy equipped with simulated spring-type muscles. Cervical muscle responses including strain and load of the sternocleidomastoid (SCM), splenius capitis (SPL), and trapezius (TRP) were analyzed, and muscle injury was assessed. The SCM, SPL, and TRP suffered average peak muscle strains of 21%, 40%, and 23%, respectively, exceeding the injury threshold. The average peak muscle loads of the SCM, SPL and TRP were 11 N, 25 N, and 25 N, respectively, lower than the ultimate failure load. The SPL endured the largest injury, while the injuries to the SCM and TRP were relatively small. This is a preliminary study to assess the cervical muscle of driver during a frontal vehicle collision. This study provides a foundation for investigating the muscle response and injury in sled test environments, which can lead to the improvement of occupant protections. PMID:26406056

  20. A system for the study of visuomotor coordination during reaching for moving targets.

    PubMed

    Schenk, T; Philipp, J; Häussler, A; Hauck, A; Hermsdörfer, J; Mai, N

    2000-07-31

    Prehensile behavior is a popular task in current research on human motor control. Most studies on reaching used stationary target objects and, therefore, most models do not address the challenges the motor system must respond to when reaching for moving objects. The machines used in earlier studies to produce object motion offered a limited range of trajectories and restricted control over various movement parameters. We have developed a device that allows a great variety of object trajectories along a flat-table surface and gives the experimenter full control over all movement parameters. A linear positioning system is used to move a sled beneath the table surface. Magnetic coupling transfers the sled's movement to the target object on the tabletop. This arrangement allows fast movements of the object (up to 5 m/s) and at the same time protects subjects from any harm due to the moving parts. The system is connected to LC shutter glasses, a 3-D movement registration device, and a switch that detects the onset of hand motion. This allows the selective withdrawal of vision during the reaching task or the introduction of changes in the object motion depending on the subject's reactions. PMID:11040360

  1. Glaciologist studies Greenland snow conditions and helps calibrate CryoSat instrument

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2011-08-01

    GREENLAND—On a typically frigid mid-July day at Summit Station, almost smack in the middle of Greenland, with the temperature hovering around -10°C, Elizabeth Morris and John Sweeny were bundled up against the cold atop their black Ski-Doo snowmobiles, which Morris described as being similar to motorcycles on ski tracks. They drove the vehicles—without yet attaching three wooden sleds that would be pulled during their summer scientific traverse across part of central Greenland—on a practice spin along the perimeter of Summit's groomed, approximately 4600-meter × 60-meter snow runway. One of the longest runways in the world, it lies atop 3.2 kilometers of ice, with the horizon stretching in every direction. Morris, a glaciologist who is a senior associate at the Scott Polar Research Institute at Cambridge University, United Kingdom, and Sweeny, her polar guide, were taking advantage of an unexpected extra day at Summit, a scientific research station sponsored by the U.S. National Science Foundation (NSF), before the traverse began. They hoped that the socked-in visibility just a few hours earlier that morning, 16 July, would not be repeated the following day so that a U.S. Air National Guard 109th Airlift Wing C-130 cargo plane would be cleared to fly to Summit from Kangerlussuaq on Greenland's west coast with needed supplies. Morris and Sweeny would load up each sled with about 270 kilograms of gear.

  2. The molecular gas in luminous infrared galaxies - I. CO lines, extreme physical conditions and their drivers

    NASA Astrophysics Data System (ADS)

    Papadopoulos, Padelis P.; van der Werf, Paul P.; Xilouris, E. M.; Isaak, K. G.; Gao, Yu; Mühle, S.

    2012-11-01

    We report results from a large molecular line survey of luminous infrared galaxies (LIRGs; L IR ≳1011 L) in the local Universe (z ≤ 0.1), conducted during the last decade with the James Clerk Maxwell Telescope and the IRAM 30-m telescope. This work presents the CO and 13CO line data for 36 galaxies, further augmented by multi-J total CO line luminosities available for other infrared (IR) bright galaxies from the literature. This yields a combined sample of N = 70 galaxies with the star formation (SF) powered fraction of their IR luminosities spanning L IR (*)˜(1010-2×1012) L and a wide range of morphologies. Simple comparisons of their available CO spectral line energy distributions (SLEDs) with local ones, as well as radiative transfer models, discern a surprisingly wide range of average interstellar medium (ISM) conditions, with most of the surprises found in the high-excitation regime. These take the form of global CO SLEDs dominated by a very warm (Tkin ≳100 K) and dense (n ≥ 104 cm-3) gas phase, involving galaxy-sized (˜(few) × 109 M⊙) gas mass reservoirs under conditions that are typically found only for ˜(1-3) per cent of mass per typical SF molecular cloud in the Galaxy. Furthermore, some of the highest excitation CO SLEDs are found in ultraluminous infrared galaxies (ULIRGs; LIR ≥ 1012 L⊙) and surpass even those found solely in compact SF-powered hot spots in Galactic molecular clouds. Strong supersonic turbulence and high cosmic ray energy densities rather than far-ultraviolet/optical photons or supernova remnant induced shocks from individual SF sites can globally warm the large amounts of dense gas found in these merger-driven starbursts and easily power their extraordinary CO line excitation. This exciting possibility can now be systematically investigated with Herschel and the Atacama Large Milimeter Array (ALMA). As expected for an IR-selected (and thus SF rate selected) galaxy sample, only few 'cold' CO SLEDs are found, and for

  3. [Continuous renal replacement therapies (CRRT) will remain the most widely adopted dialysis modality in the critically ill].

    PubMed

    Morabito, S; Pistolesi, V; Cibelli, L; Pierucci, A

    2009-01-01

    In the last 10-15 years, user-friendly continuous renal replacement therapy (CRRT) machines have played a major role in increasing the popularity of these techniques in intensive care settings. At present it is not clear which modality of renal replacement therapy (RRT) is optimal for critically ill patients with acute kidney injury (AKI). The choice between different modalities should therefore not be based on unproven ''outcome'' advantages but on evaluation of the clinical picture and logistical circumstances. In hypercatabolic patients, CRRT and sustained low-efficiency dialysis (SLED) have been shown to provide similar metabolic control, but uncontrolled studies suggested a better hemodynamic stability during CRRT, intended as a higher mean arterial pressure and/or less frequent need to increase inotropic or vasoactive drugs. The incidence of hemorrhagic complications is higher with CRRT; however, in particular conditions, such as in patients at high risk of bleeding, CRRT can be performed without anticoagulation or with the use of alternative anticoagulation protocols. Among the different modalities, regional anticoagulation with citrate appears to be the most promising, and the continuous development of simplified protocols for citrate CRRT might facilitate the more extensive use of this technique in the near future. The presence of a mismatch between prescribed and delivered dialysis dose is frequently reported as an important drawback of CRRT. However, data from a recent study designed to evaluate the prognostic impact of the intensity of renal support in critically ill patients with AKI showed that the target Kt/V was obtained in only 67-69% of intermittent hemodialysis (IHD) sessions. Data from several studies comparing the costs of different RRT modalities showed that CRRT is more expensive than IHD or SLED. However, the costs related to SLED can fluctuate within a wide range and in particular settings the higher costs of CRRT could be partially

  4. The molecular gas in Luminous Infrared Galaxies: a new emergent picture

    NASA Astrophysics Data System (ADS)

    Papadopoulos, Padelis P.; Zhang, Zhi-Yu; Weiss, Axel; van der Werf, Paul; Isaak, Kate; Gao, Yu; Xilouris, Manolis; Greve, Thomas R.

    2013-03-01

    Results from a large, multi-J CO, 13CO, and HCN line survey of Luminous Infrared Galaxies (LIRGs: LIR≥ 1010 L⊙) in the local Universe (z≤0.1), complemented by CO J=4-3 up to J=13-12 observations from the Herschel Space Observatory (HSO), paints a new picture for the average conditions of the molecular gas of the most luminous of these galaxies with turbulence and/or large cosmic ray (CR) energy densities UCR rather than far-UV/optical photons from star-forming sites as the dominant heating sources. Especially in ULIRGs (LIR>1012 L⊙) the Photon Dominated Regions (PDRs) can encompass at most a few % of their molecular gas mass while the large UCR˜ 103 UCR, Galaxy, and the strong turbulence in these merger/starbursts, can volumetrically heat much of their molecular gas to Tkin˜ (100-200) K, unhindered by the high dust extinctions. Moreover the strong supersonic turbulence in ULIRGs relocates much of their molecular gas at much higher average densities (≥104 cm-3) than in isolated spirals (˜ 102-103 cm-3). This renders low-J CO lines incapable of constraining the properties of the bulk of the molecular gas in ULIRGs, with substantial and systematic underestimates of its mass possible when only such lines are used. Finally a comparative study of multi-J HCN lines and CO SLEDs from J=1-0 up to J=13-12 of NGC 6240 and Arp 193 offers a clear example of two merger/starbursts whose similar low-J CO SLEDs, and LIR/LCO,1-0 and LHCN, 1-0/LCO,1-0 ratios (proxies of the so-called SF efficiency and dense gas mass fraction), yield no indications about their strongly diverging CO SLEDs beyond J=4-3, and ultimately the different physical conditions in their molecular ISM. The much larger sensitivity of ALMA and its excellent site in the Atacama desert now allows the observations necessary to assess the dominant energy sources of the molecular gas and its mass in LIRGs without depending on the low-J CO lines.

  5. CO Spectral Line Energy Distributions of Infrared-Luminous Galaxies and Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Papadopoulos, Padeli P.; van der Werf, Paul; Isaak, Kate; Xilouris, Emmanuel M.

    2010-06-01

    We report on new sensitive CO J = 6-5 line observations of several luminous infrared galaxies (LIRGs; L IR(8-1000 μm) >~ 1011 L sun), 36% (8/22) of them ultraluminous infrared galaxies (ULIRGs) (L IR>1012 L sun), and two powerful local active galactic nuclei (AGNs)—the optically luminous QSO PG 1119+120 and the powerful radio galaxy 3C 293—using the James Clerk Maxwell Telescope on Mauna Kea in Hawaii. We combine these observations with existing low-J CO data and dust emission spectral energy distributions in the far-infrared-submillimeter from the literature to constrain the properties of the star-forming interstellar medium (ISM) in these systems. We then build the first local CO spectral line energy distributions (SLEDs) for the global molecular gas reservoirs that reach up to high J-levels. These CO SLEDs are neither biased by strong lensing (which affects many of those constructed for high-redshift galaxies), nor suffer from undersampling of CO-bright regions (as most current high-J CO observations of nearby extended systems do). We find: (1) a significant influence of dust optical depths on the high-J CO lines, suppressing the J = 6-5 line emission in some of the most IR-luminous LIRGs, (2) low global CO line excitation possible even in vigorously star-forming systems, (3) the first case of a shock-powered high-excitation CO SLED in the radio galaxy 3C 293 where a powerful jet-ISM interaction occurs, and (4) unusually highly excitated gas in the optically powerful QSO PG 1119+120. In Arp 220 and possibly other (U)LIRGs very faint CO J = 6-5 lines can be attributed to significant dust optical depths at short submillimeter wavelengths immersing those lines in a strong dust continuum, and also causing the C+ line luminosity deficit often observed in such extreme starbursts. Re-analysis of the CO line ratios available for submillimeter galaxies suggests that similar dust opacities also may be present in these high-redshift starbursts, with genuinely low

  6. Genomic deletion of CNGB3 is identical by descent in multiple canine breeds and causes achromatopsia

    PubMed Central

    2013-01-01

    Background Achromatopsia is an autosomal recessive disease characterized by the loss of cone photoreceptor function that results in day-blindness, total colorblindness, and decreased central visual acuity. The most common causes for the disease are mutations in the CNGB3 gene, coding for the beta subunit of the cyclic nucleotide-gated channels in cones. CNGB3-achromatopsia, or cone degeneration (cd), is also known to occur in two canine breeds, the Alaskan malamute (AM) and the German shorthaired pointer. Results Here we report an in-depth characterization of the achromatopsia phenotype in a new canine breed, the miniature Australian shepherd (MAS). Genotyping revealed that the dog was homozygous for a complete genomic deletion of the CNGB3 gene, as has been previously observed in the AM. Identical breakpoints on chromosome 29 were identified in both the affected AM and MAS with a resulting deletion of 404,820 bp. Pooled DNA samples of unrelated purebred Australian shepherd, MAS, Siberian husky, Samoyed and Alaskan sled dogs were screened for the presence of the affected allele; one Siberian husky and three Alaskan sled dogs were identified as carriers. The affected chromosomes from the AM, MAS, and Siberian husky were genotyped for 147 SNPs in a 3.93 Mb interval within the cd locus. An identical shared affected haplotype, 0.5 Mb long, was observed in all three breeds and defined the minimal linkage disequilibrium (LD) across breeds. This supports the idea that the mutated allele was identical by descent (IBD). Conclusion We report the occurrence of CNGB3-achromatopsia in a new canine breed, the MAS. The CNGB3-deletion allele previously described in the AM was also observed in a homozygous state in the affected MAS, as well as in a heterozygous carrier state in a Siberian husky and Alaskan sled dogs. All affected alleles were shown to be IBD, strongly suggesting an affected founder effect. Since the MAS is not known to be genetically related to the AM, other

  7. Consideration of wear rates at high velocity

    NASA Astrophysics Data System (ADS)

    Hale, Chad S.

    The development of the research presented here is one in which high velocity relative sliding motion between two bodies in contact has been considered. Overall, the wear environment is truly three-dimensional. The attempt to characterize three-dimensional wear was not economically feasible because it must be analyzed at the micro-mechanical level to get results. Thus, an engineering approximation was carried out. This approximation was based on a metallographic study identifying the need to include viscoplasticity constitutive material models, coefficient of friction, relationships between the normal load and velocity, and the need to understand wave propagation. A sled test run at the Holloman High Speed Test Track (HHSTT) was considered for the determination of high velocity wear rates. In order to adequately characterize high velocity wear, it was necessary to formulate a numerical model that contained all of the physical events present. The experimental results of a VascoMax 300 maraging steel slipper sliding on an AISI 1080 steel rail during a January 2008 sled test mission were analyzed. During this rocket sled test, the slipper traveled 5,816 meters in 8.14 seconds and reached a maximum velocity of 1,530 m/s. This type of environment was never considered previously in terms of wear evaluation. Each of the features of the metallography were obtained through micro-mechanical experimental techniques. The byproduct of this analysis is that it is now possible to formulate a model that contains viscoplasticity, asperity collisions, temperature and frictional features. Based on the observations of the metallographic analysis, these necessary features have been included in the numerical model, which makes use of a time-dynamic program which follows the movement of a slipper during its experimental test run. The resulting velocity and pressure functions of time have been implemented in the explicit finite element code, ABAQUS. Two-dimensional, plane strain models

  8. On-ice vibroseis and snowstreamer systems for geoscientific research

    NASA Astrophysics Data System (ADS)

    Eisen, Olaf; Hofstede, Coen; Diez, Anja; Kristoffersen, Yngve; Lambrecht, Astrid; Mayer, Christoph; Blenkner, Rick; Hilmarsson, Sverrir

    2015-03-01

    We present implementations of vibroseis system configurations with a snowstreamer for over-ice long-distance seismic traverses (>100 km). The configurations have been evaluated in Antarctica on ice sheet and ice shelf areas in the period 2010-2014. We discuss results of two different vibroseis sources: Failing Y-1100 on skis with a peak force of 120 kN in the frequency range 10-110 Hz; IVI EnviroVibe with a nominal peak force of 66 kN in the nominal frequency range 10-300 Hz. All measurements used a well-established 60 channel 1.5 km snowstreamer for the recording. Employed forces during sweeps were limited to less than 80% of the peak force. Maximum sweep frequencies, with a typical duration of 10 s, were 100 and 250 Hz for the Failing and EnviroVibe, respectively. Three different concepts for source movement were employed: the Failing vibrator was mounted with wheels on skis and pulled by a Pistenbully snow tractor. The EnviroVibe was operated self-propelled on Mattracks on the Antarctic plateau. This lead to difficulties in soft snow. For later implementations the EnviroVibe with tracks was put on a polyethylene (PE) sled. The sled had a hole in the center to lower the vibrator baseplate directly onto the snow surface. With the latter setup, data production varied between 20 km/day for 6-fold and 40 km/day for single fold for 9 h/day of measurements. The combination of tracks with the PE-sled was especially advantageous on hard and rough surfaces because of the flexibility of each component and the relatively lose mounting. The systems presented here are suitable to obtain data of subglacial and sub-seabed sediment layers and englacial layering in comparable quality as obtained from marine geophysics and land-based explosive surveys. The large offset aperture of the streamer overcomes limitations of radar systems for imaging of steep along-track subglacial topography. With joint international scientific and logistic efforts, large-scale mapping of Antarctica

  9. Helium and neon isotopes in deep Pacific Ocean sediments

    NASA Technical Reports Server (NTRS)

    Nier, A. O.; Schlutter, D. J.; Brownlee, D. E.

    1990-01-01

    Helium and neon concentration measurements, along with isotope ratio determinations, have been made for particles collected in the deep Pacific with a magnetic sled, and they are believed to be of extraterrestrial origin. Analyses were made for samples consisting of composites of many extremely fine particles and for several individual particles large enough to contain sufficient gas for analysis but small enough to escape melting in their passage through the atmosphere. Step-heating was employed to extract the gas. Cosmic-ray spallation products or solar-wind helium and neon, if present, were not abundant enough to account for the isotopic compositions measured. In the case of the samples of magnetic fines, the low temperature extractions provided elemental and isotopic ratios in the general range found for the primordial gas in carbonaceous chondrites and gas-rich meteorites. The isotopic ratios found in the high temperature extractions suggest the presence of solar-flare helium and neon.

  10. Experiments on the Richtmyer-Meshkov Instability of Incompressible Fluids

    NASA Technical Reports Server (NTRS)

    Jacobs, J.; Niederhaus, C.

    2000-01-01

    Richtmyer-Meshkov (R-M) instability occurs when two different density fluids are impulsively accelerated in the direction normal to their nearly planar interface. The instability causes small perturbations on the interface to grow and possibly become turbulent given the proper initial conditions. R-M instability is similar to the Rayleigh-Taylor (R-T) instability, which is generated when the two fluids undergo a constant acceleration. R-M instability is a fundamental fluid instability that is important to fields ranging from astrophysics to high-speed combustion. For example, R-M instability is currently the limiting factor in achieving a net positive yield with inertial confinement fusion. The experiments described here utilize a novel technique that circumvents many of the experimental difficulties previously limiting the study of the R-M instability. A Plexiglas tank contains two unequal density liquids and is gently oscillated horizontally to produce a controlled initial fluid interface shape. The tank is mounted to a sled on a high speed, low friction linear rail system, constraining the main motion to the vertical direction. The sled is released from an initial height and falls vertically until it bounces off of a movable spring, imparting an impulsive acceleration in the upward direction. As the sled travels up and down the rails, the spring retracts out of the way, allowing the instability to evolve in free-fall until impacting a shock absorber at the end of the rails. The impulsive acceleration provided to the system is measured by a piezoelectric accelerometer mounted on the tank, and a capacitive accelerometer measures the low-level drag of the bearings. Planar Laser-Induced Fluorescence is used for flow visualization, which uses an Argon ion laser to illuminate the flow and a CCD camera, mounted to the sled, to capture images of the interface. This experimental study investigates the instability of an interface between incompressible, miscible liquids

  11. Polymer Infiltration Studies

    NASA Technical Reports Server (NTRS)

    Marchello, Joseph M.

    1993-01-01

    Significant progress has been made on the preparation of carbon fiber composites using advanced polymer resins during the past three months. Current and ongoing research activities reported herein include: (1) Prepregger Hot Sled Operation; (2) Ribbonizing Powder-Impregnated Towpreg; (3) Textile Composites from Powder-Coated Towpreg: Role of Bulk Factor; and (4) Powder Curtain Prepreg Process. During the coming months research will be directed toward further development of the new powder curtain prepregging method and on ways to customize dry powder towpreg for textile and robotic applications in aircraft part fabrication. Studies of multi-tow powder prepregging and ribbon preparation will be conducted in conjunction with continued development of prepegging technology and the various aspects of composite part fabrication using customized towpreg. Also, work will continue on the analysis of the new solution prepegger.

  12. Risk assessment and its application to flight safety analysis

    SciTech Connect

    Keese, D.L.; Barton, W.R.

    1989-12-01

    Potentially hazardous test activities have historically been a part of Sandia National Labs mission to design, develop, and test new weapons systems. These test activities include high speed air drops for parachute development, sled tests for component and system level studies, multiple stage rocket experiments, and artillery firings of various projectiles. Due to the nature of Sandia's test programs, the risk associated with these activities can never be totally eliminated. However, a consistent set of policies should be available to provide guidance into the level of risk that is acceptable in these areas. This report presents a general set of guidelines for addressing safety issues related to rocket flight operations at Sandia National Laboratories. Even though the majority of this report deals primarily with rocket flight safety, these same principles could be applied to other hazardous test activities. The basic concepts of risk analysis have a wide range of applications into many of Sandia's current operations. 14 refs., 1 tab.

  13. GIF Animation of Mode Shapes and Other Data on the Internet

    NASA Technical Reports Server (NTRS)

    Pappa, Richard S.

    1998-01-01

    The World Wide Web abounds with animated cartoons and advertisements competing for our attention. Most of these figures are animated Graphics Interchange Format (GIF) files. These files contain a series of ordinary GIF images plus control information, and they provide an exceptionally simple, effective way to animate on the Internet. To date, however, this format has rarely been used for technical data, although there is no inherent reason not to do so. This paper describes a procedure for creating high-resolution animated GIFs of mode shapes and other types of structural dynamics data with readily available software. The paper shows three example applications using recent modal test data and video footage of a high-speed sled run. A fairly detailed summary of the GIF file format is provided in the appendix. All of the animations discussed in the paper are posted on the Internet available through the following address: http://sdb-www.larc.nasa.gov/.

  14. The aerodynamic challenges of SRB recovery

    NASA Technical Reports Server (NTRS)

    Bacchus, D. L.; Kross, D. A.; Moog, R. D.

    1985-01-01

    Recovery and reuse of the Space Shuttle solid rocket boosters was baselined to support the primary goal to develop a low cost space transportation system. The recovery system required for the 170,000-lb boosters was for the largest and heaviest object yet to be retrieved from exoatmospheric conditions. State-of-the-art design procedures were ground-ruled and development testing minimized to produce both a reliable and cost effective system. The ability to utilize the inherent drag of the boosters during the initial phase of reentry was a key factor in minimizing the parachute loads, size and weight. A wind tunnel test program was devised to enable the accurate prediction of booster aerodynamic characteristics. Concurrently, wind tunnel, rocket sled and air drop tests were performed to develop and verify the performance of the parachute decelerator subsystem. Aerodynamic problems encountered during the overall recovery system development and the respective solutions are emphasized.

  15. 7. View of interior of Lock No. 2 on George ...

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

    7. View of interior of Lock No. 2 on George washington 'Potowmack' Canal at Great Falls, Virginia. This lock is about 15 ft. in depth and possibly 70 or 60 ft. in length. Some 15 or 20 years ago, when a restoration was crudely attempted, the old oaken flooring, which was invariably placed at the bottom of canal locks, was roughly torn up and destroyed. The trunks and stumps of gigantic trees still remain from this restorative effort, and their girth indicates again the antiquity of this evidence of George Washington's work as an engineer. The stones are of the red Seneca type and were evidently ferried from the Maryland side above the dam and then brought by sled or rollers to this location. These stones were beautifully hand-cut and fitted with ... - Potowmack Company: Great Falls Canal, Lock No. 2, Great Falls, Fairfax County, VA

  16. Performance evaluation of a redundant inertial measurement unit

    NASA Astrophysics Data System (ADS)

    Bletsos, N. A.; Blair, W. P.

    A description is given of the redundant inertial measurement unit (RIMU) developed for the Inertial Upper Stage. The RIMU is a high-performance strapped-down system, which is internally redundant to the extent that the navigation system will continue to operate past any single-point failure; all single-point failures are detectable and isolated by failure detection and isolation algorithms incorporated in the navigation computers. The performance of the RIMU was evaluated in a sled test in a highly dynamic environment prior to first flight. The results showed: no failures of the RIMU/computer in RST4; overall performance as designed; navigation accuracy within requirements; and redundancy management performed as designed.

  17. 3. Credit USAF, ca. 1945. Original housed in the Records ...

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

    3. Credit USAF, ca. 1945. Original housed in the Records of the Defense Intelligence Agency. Record Group 373. National Archives. Cartographic and Architectural Branch. Washington, D.C. Aerial orthophoto map 16PS5M79-IV23 of Muroc Flight Test Base (North Base), north faces up with runway at the top and Rogers Dry Lake at the lower right. Ammunition huts (not extant in 1995) appear in a cluster just south of the west end of the runway. Note runway markings on lakebed. Linear feature at very top of image is rocket sled test track designed and built 1944-1945. - Edwards Air Force Base, North Base, North Base Road, Boron, Kern County, CA

  18. Thresholds for the perception of whole-body linear sinusoidal motion in the horizontal plane

    NASA Technical Reports Server (NTRS)

    Mah, Robert W.; Young, Laurence R.; Steele, Charles R.; Schubert, Earl D.

    1989-01-01

    An improved linear sled has been developed to provide precise motion stimuli without generating perceptible extraneous motion cues (a noiseless environment). A modified adaptive forced-choice method was employed to determine perceptual thresholds to whole-body linear sinusoidal motion in 25 subjects. Thresholds for the detection of movement in the horizontal plane were found to be lower than those reported previously. At frequencies of 0.2 to 0.5 Hz, thresholds were shown to be independent of frequency, while at frequencies of 1.0 to 3.0 Hz, thresholds showed a decreasing sensitivity with increasing frequency, indicating that the perceptual process is not sensitive to the rate change of acceleration of the motion stimulus. The results suggest that the perception of motion behaves as an integrating accelerometer with a bandwidth of at least 3 Hz.

  19. Observation of particle bursts in the tail of planet Mars onboard the PHOBOS 2 spacecraft

    NASA Astrophysics Data System (ADS)

    Kirsch, E.; McKenna-Lawlor, S.; Afonin, V. V.; Schwingenschuh, K.; Keppler, E.; Witte, M.; Osullivan, D.; Thompson, A.

    1992-09-01

    Particle and magnetic field measurements obtained onboard the Phobos 2 spacecraft near planet Mars in Feb./Mar. 1989 are used to study particle bursts generated in the tail of Mars. The Phobos 2 spacecraft reached planet Mars on 29 Jan. 1989 and performed elliptical and circular orbits until 26 Mar. 1989. Especially during the circular orbits, particle bursts (Ep = 35 to 200 keV) were observed by the Solar Low Energy Detector (SLED) in the tail region of Mars. Simultaneously, the magnetic field was measured by the MAGMA experiment. It was found that the particle bursts appeared during short term directional changes of the Bx component which can be interpreted as an indication of the formation on an X-line. The bursts appear to be similar to those found in the geomagnetic field and are likely to have originated by reconnection processes in the Mars tail.

  20. Radar sensor for an autonomous Antarctic explorer

    NASA Astrophysics Data System (ADS)

    Foessel, Alex; Apostolopoulos, Dimi; Whittaker, William L.

    1999-01-01

    The localization and identification of antarctic meteorites is a task of great scientific interest and with implications to planetary exploration. Autonomous search for antarctic meteorites presents a profound technical challenge. Ground Penetrating Radar (GPR) holds the prospect to safeguard antarctic robot from terrain dangers and detect subsurface objects. In January 1998, we validated a 500 MHz GPR sensor as part of a field robotic technology demonstration at Patriot Hills, Antarctica. We deployed the sensor from a sled and integrate with position and attitude instruments to perform field measurements. Data was acquired under different conditions and in multiple locations. The radar detected hidden crevasses from 50 cm. distance, thus showing its merit as a rover safeguarding device. It also localized 5 cm. rocks ins now and ice. Moreover, the radar data was used to characterize snow/ice/bedrock stratigraphy. GPR position measurements enabled ground truth and mapping of the location of hazards and interesting subsurface objects and features.

  1. Practical geological comparison of some seafloor survey instruments

    NASA Astrophysics Data System (ADS)

    Kleinrock, Martin C.; Hey, R. N.; Theberge, A. E., Jr.

    1992-07-01

    Seafloor survey instruments are integral to the study of marine geology. Because understanding their resolution and limitations is critical, we compare how different survey systems represent the seafloor. Coincident data collected at the Galapagos propagator (GLORIA, SeaMARC II, Sea Beam, Deep-Tow, camera sled, and Alvin) allow comparisons of how well seafloor features (e.g., faults and volcanoes) observed and characterized in high resolution data are represented in lower resolution, coarser-scale data sets. Our reported values for the minimum sizes of detected and well-represented features show that practical geological resolutions are generally ˜2-10 times lower than theoretical resolutions; care must be taken in evaluating which system to use to address a particular problem.

  2. The Molecular Gas in Luminous Infrared Galaxies. II. Extreme Physical Conditions and Their Effects on the X co Factor

    NASA Astrophysics Data System (ADS)

    Papadopoulos, Padelis P.; van der Werf, Paul; Xilouris, E.; Isaak, Kate G.; Gao, Yu

    2012-05-01

    In this work, we conclude the analysis of our CO line survey of luminous infrared galaxies (LIRGs: L IR >~ 1011 L ⊙) in the local universe (Paper I) by focusing on the influence of their average interstellar medium (ISM) properties on the total molecular gas mass estimates via the so-called X co = M(H2)/L co, 1-0 factor. One-phase radiative transfer models of the global CO spectral line energy distributions (SLEDs) yield an X co distribution with langX corang ~ (0.6 ± 0.2) M ⊙ (K km s-1 pc2)-1 over a significant range of average gas densities, temperatures, and dynamic states. The latter emerges as the most important parameter in determining X co, with unbound states yielding low values and self-gravitating states yielding the highest ones. Nevertheless, in many (U)LIRGs where available higher-J CO lines (J = 3-2, 4-3, and/or J = 6-5) or HCN line data from the literature allow a separate assessment of the gas mass at high densities (>=104 cm-3) rather than a simple one-phase analysis, we find that near-Galactic X co ~ (3-6) M ⊙ (K km s-1 pc2)-1 values become possible. We further show that in the highly turbulent molecular gas in ULIRGs, a high-density component will be common and can be massive enough for its high X co to dominate the average value for the entire galaxy. Using solely low-J CO lines to constrain X co in such environments (as has been the practice up until now) may have thus resulted in systematic underestimates of molecular gas mass in ULIRGs, as such lines are dominated by a warm, diffuse, and unbound gas phase with low X co but very little mass. Only well-sampled high-J CO SLEDs (J = 3-2 and higher) and/or multi-J observations of heavy rotor molecules (e.g., HCN) can circumvent such a bias, and the latter type of observations may have actually provided early evidence of it in local ULIRGs. The only way that the global X co of such systems could be significantly lower than Galactic is if the average dynamic state of the dense gas is strongly

  3. Colloquium on Phobos-Mars Mission, Paris, France, Oct. 23-27, 1989, Proceedings

    NASA Astrophysics Data System (ADS)

    Blamont, J. E.

    1991-02-01

    A preliminary analysis of results obtained from the Phobos-Mars missions is presented. Topics include solar X-ray observation with the RF-15 instrument, new insights on cosmic gamma-ray bursts from the APEX experiment, EUV observations of solar flares from Mars, short term variability of the power spectrum of 5-min oscillations of the sun, and results of the LET experiment. Plasma waves around Mars, tails of Phobos and Deimos in the solar wind and in the Martian magnetosphere, the HARP plasma experiment onboard the Phobos 2 spacecraft, Martian atmosphere studies from the ISM experiment, low-energy charged particles in near Martian space from SLED and LET experiments aboard the Phobos 2 spacecraft, and submillimeter observations of CO in Mars' atmosphere are also discussed. Results of TV imaging of Phobos, color decorrelation for the Phobos mission camera experiment, slope variations on the surface of Phobos, and an interpretation of the surface brightness of Phobos are given.

  4. A Herschel Spectroscopic Survey of Warm Molecular Gas in Local Infrared Luminous Galaxies

    NASA Astrophysics Data System (ADS)

    Lu, N.; Zhao, Y.; Xu, C. K.; Gao, Y.; GOALS FTS Team

    2013-03-01

    We describe an on-going 194-671 μm spectroscopic survey of a flux-limited sample of 125 local luminous infrared galaxies (LIRGs) with Herschel SPIRE Fourier Transform Spectrometer (FTS). The survey targets primarily the CO spectral line energy distribution (SLED), from J = 4-3 up to J = 13-12, to probe dense and warm molecular gas that should play an intimate role in star formation and/or active galactic nuclear activities in these galaxies. The program is about 75% finished. At S/N > 5, besides the CO lines, we also detected [N ii] 205 μm and [C i] 370 μm (3 P 2 - 3P1) lines in every target observed. In about half of the observed targets, we also detected [C i] 609 μm (3 P 1 - 3P0).

  5. Bioscience experiments in the German Spacelab mission D-1: Introduction and summary

    NASA Astrophysics Data System (ADS)

    Horneck, G.; Greger, G.; Sahm, P. R.

    The German Spacelab mission D-1 was performed from 30 October through 6 November 1985. Payload operation in orbit was managed by DFVLR for the Federal Ministry of Research and Technology. The scientific program of the mission placed emphasis on microgravity research. In bioscience, the role of gravity in vital functions of biological systems was investigated, such as intracellular and intercellular interactions, developmental processes as well as regulation and adaptation in highly organized systems including human beings. In addition, the biological significance of cosmic radiation or altered zeitgeber within the complex matrix of all relevant spaceflight components were studied. Most of the experiments were accommodated in the following three payload elements: The Bioscience Experiment Package, and the ESA facilities Vestibular Sled and BIORACK. The information gained from the individual experiments will be compiled to help answer pending questions of space bioscience.

  6. Energetic particles (greater than 34 KeV - 3.2 MeV) in the deep Martian magnetotail (X = 15.5 RM), modeling of the Martian bow shock and the influence of low solar wind pressure on Mars as an obstacle

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, S. M. P.; Afonin, V. V.

    1992-09-01

    The first observations of energetic particles (range greater than 34 KeV to less than 3.2 MeV) in the tailward part of the Martian magnetosheath, as well as during crossings of the Martian bow shock within the deep magnetotail (X = 15.5 RM), are reported. This was done by using data from the SLED (Solar Low Energy Detector) instrument on Phobos 2. The energies observed cannot be attained by the pickup process acting alone. Sporadic field line merging at the dayside of the planet would conceivably accelerate the particles to the observed energies. The presence of an unusually weak dynamic solar wind pressure during orbits 3 and 4 suggests that a weak intrinsic field could have expanded outwards under these conditions to provide a dayside obstacle radius for Mars of up to about 2000 km.

  7. Keck Interferometer autoaligner: algorithms and techniques

    NASA Astrophysics Data System (ADS)

    Hrynevych, Michael A.; Tsubota, Kevin; Smythe, Robert F.; Dahl, Wayne; Bell, James; Colavita, M. M.; Gathright, John; Meggars, Forrest; Neyman, Christopher R.; Rudeen, Andy C.; van Belle, Gerard T.; Wizinowich, Peter L.

    2004-10-01

    The Keck Interferometer includes an autoalignment system consisting of pop-up targets located at strategic locations along the beam trains of each arm of the instrument along with a sensor and control system. We briefly describe the hardware of the system and then proceed to a description of the two operational modes of the system. These are: 1) to provide an initial alignment of the coude paths in each arm, and 2) to recover coude alignments between changes of the static delay sled positions. For the initial alignment mode, we review the system performance requirements along with the software used for image acquisition and centroiding. For coudé alignment recovery, we describe beam-train surveys through the static delay (Long Delay Line) and criteria for a successful recovery of a coudé alignment. Finally, we describe the results of testing of the autoalignment system.

  8. Prediction of the effect of an extreme solar event on the Martian environment using a 3-D, self consistent hybrid model supplemented by test particle simulations.

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, Susan; Kallio, Esa; Dyadechkin, Sergey; Jarvinen, Riku; Janhunen, Pekka

    2010-05-01

    Energetic particle data recorded by the SLED and LET instruments aboard the Phobos-2 spacecraft while in circular orbit about Mars showed the presence from 6 > 26 March, 1989, in association with an extreme solar event, of intense ambient particle radiation (> 30 MeV) punctuated by traveling interplanetary shocks. The response of the Martian environment to the March 1989 solar disturbances is modeled using a 3-D, self-consistent, hybrid model (HYB-Mars) supplemented by test particle simulations. In HYB-Mars ions are modeled as particles while electrons form a massless, charge neutralizing, fluid. The magnetic and electric fields present during the March 1989 activity are each derived from HYB- Mars while the high energy ion populations are analyzed using test particle simulations. Finally, the predictions of the model are validated by comparing the simulated properties of the disturbed Martian environment with the in situ observations.

  9. Energetic ions in the close environment of Mars and particle shadowing by the planet

    NASA Astrophysics Data System (ADS)

    Afonin, V.; Gringauz, K.; McKenna-Lawlor, S.; Kecskemety, K.; Keppler, E.

    1989-10-01

    The twin-telescope particle-detector system, SLED, aboard Phobos 2 recorded flux enhancements in the range 30-350 keV in the same general location in the close environment of Mars, over eight days at about 900 km altitude in three successive elliptical orbits. Here, possible interpretations of these observations are presented. Energy-related particle shadowing by the body of Mars was also detected, and the data indicate that this effect occurred in less than 20 percent of the 114 circular orbits around Mars because of the nutation of the spacecraft. The influence of magnetic fields in allowing particles to reach the detector under potentially screened conditions is discussed.

  10. Technology requirements for advanced earth-orbital transportation systems: Summary report. [single stage to orbit vehicles

    NASA Technical Reports Server (NTRS)

    Haefeli, R. C.; Littler, E. G.; Hurley, J. B.; Winter, M. G.

    1977-01-01

    Areas of advanced technology that are either critical or offer significant benefits to the development of future Earth-orbit transportation systems were identified. Technology assessment was based on the application of these technologies to fully reusable, single-state-to-orbit (SSTO) vehicle concepts with horizontal landing capability. Study guidelines included mission requirements similar to space shuttle, an operational capability beginning in 1995, and main propulsion to be advanced hydrogen-fueled rocket engines. The technical and economic feasibility of this class of SSTO concepts were evaluated as well as the comparative features of three operational take-off modes, which were vertical boost, horizontal sled launch, and horizontal take-off with subsequent inflight fueling. Projections of both normal and accelerated technology growth were made. Figures of merit were derived to provide relative rankings of technology areas. The influence of selected accelerated areas on vehicle design and program costs was analyzed by developing near-optimum point designs.

  11. Deployment loads data from a free-flight investigation of all flexible parawings having 371.612 sq meters (4000 sq feet) of wing area

    NASA Technical Reports Server (NTRS)

    Croom, D. R.

    1971-01-01

    A free-flight test program to determine the deployment characteristics of all-flexible parawings was conducted. Both single-keel and twin-keel parawings having a wing area of 4000 square feet with a five-stage reefing system were tested by use of a bomb-type instrumented test vehicle. Several twin-keel-parawing tests were also made by using an instrumented controllable sled-type test vehicle. The systems were launched from either a C-130 or a C-119 carrier airplane, and a programer parachute was used to bring the test vehicle to a proper dynamic pressure and near-vertical flight path prior to deployment of the parawing system. The free-flight deployment loads data are presented in the form of time histories of individual suspension-line loads and total loads.

  12. MIT-KSC space life sciences telescience testbed

    NASA Technical Reports Server (NTRS)

    1989-01-01

    A Telescience Life Sciences Testbed is being developed. The first phase of this effort consisted of defining the experiments to be performed, investigating the various possible means of communication between KSC and MIT, and developing software and hardware support. The experiments chosen were two vestibular sled experiments: a study of ocular torsion produced by Y axis linear acceleration, based on the Spacelab D-1 072 Vestibular Experiment performed pre- and post-flight at KSC; and an optokinetic nystagmus (OKN)/linear acceleration interaction experiment. These two experiments were meant to simulate actual experiments that might be performed on the Space Station and to be representative of space life sciences experiments in general in their use of crew time and communications resources.

  13. Results from Sandia National Laboratories/Lockheed Martin Electromagnetic Missile Launcher (EMML).

    SciTech Connect

    Lockner, Thomas Ramsbeck; Skurdal, Ben; Gaigler, Randy; Basak, L; Root, G; Aubuchon, Matthew S.; Turman, Bobby N.; Floyd, Mendel D.

    2005-05-01

    Sandia national laboratories (SNL) and lockheed martin MS2 are designing an electromagnetic missile launcher (EMML) for naval applications. The EMML uses an induction coilgun topology with the requirement of launching a 3600 lb. missile up to a velocity of 40 m/s. To demonstrate the feasibility of the electromagnetic propulsion design, a demonstrator launcher was built that consists of approximately 10% of the propulsion coils needed for a tactical design. The demonstrator verified the design by launching a 1430 lb weighted sled to a height of 24 ft in mid-December 2004 (Figure 1). This paper provides the general launcher design, specific pulsed power system component details, system operation, and demonstration results.

  14. S-Band Loads for SLAC Linac

    SciTech Connect

    Krasnykh, A.; Decker, F.-J.; LeClair, R.; /INTA Technologies, Santa Clara

    2012-08-28

    The S-Band loads on the current SLAC linac RF system were designed, in some cases, 40+ years ago to terminate 2-3 MW peak power into a thin layer of coated Kanthal material as the high power absorber [1]. The technology of the load design was based on a flame-sprayed Kanthal wire method onto a base material. During SLAC linac upgrades, the 24 MW peak klystrons were replaced by 5045 klystrons with 65+ MW peak output power. Additionally, SLED cavities were introduced and as a result, the peak power in the current RF setup has increased up to 240 MW peak. The problem of reliable RF peak power termination and RF load lifetime required a careful study and adequate solution. Results of our studies and three designs of S-Band RF load for the present SLAC RF linac system is discussed. These designs are based on the use of low conductivity materials.

  15. Review of analytical projectors and systems used in high-speed photography (Extended Abstract)

    NASA Astrophysics Data System (ADS)

    Lawrence, Robert H.

    1997-05-01

    The use of motion picture cameras and film in analyzing moving objects, particular] high speed motion, has played an important role in the access of information. Not only does film furnish a picture with high resolution, it is relatively inexpensive and easy to use. Various situations where film has been used successfu include missile firings, sled track runs, rocket lift-offs, automobile crash studie radiology studies, sports analysis, with emplasis on football, and various industri motion applications. More specifically, in research applications, the study of Met Attitude, Failure, and Position. This presentation is directed primarily to the history and development of analytica projectors used in viewing motion picture film with emphasis on high speed moving pictures in the 100 to 10,000 frames per second mode. Various types of film have been used. Cameras such as Fairchid, Fastax, PhotoSonics, Askania, Red Lake, Milliken, Bell Howell, Eastman Kodak, etc.

  16. Computer simulation of occupant neck response to airbag deployment in frontal impacts.

    PubMed

    Yang, K H; Latouf, B K; King, A I

    1992-08-01

    A mathematical simulation was performed to study the potential of head and neck injury to an unbelted driver restrained by an airbag. The baseline study represented a 50th percentile male dummy driving in a compact car with the steering wheel perpendicular to the floor. The vehicle was moving at 48 km/hour at the time of impact. Model predictions were compared with sled test results. The data agreed reasonably well. A parametric study was performed to study the effect of changing the steering wheel angle and the size of the airbag. It was found that when the standard 20 degrees angle steering wheel was used, neck joint torques were decreased by 22 percent while the resultant head acceleration increased 41 percent from the base line study. When the vertical dimension of the airbag was reduced by 10 percent, neck joint torques were increased by 14 percent, while head acceleration showed a slight decrease of 9 percent. PMID:1522726

  17. Technology requirements for advanced earth-orbital transportation systems

    NASA Technical Reports Server (NTRS)

    Haefeli, R. C.; Littler, E. G.; Hurley, J. B.; Winter, M. G.

    1977-01-01

    Areas of advanced technology that are either critical or offer significant benefits to the development of future Earth-orbit transportation systems were identified. Technology assessment was based on the application of these technologies to fully reusable, single-stage-to-orbit (SSTO) vehicle concepts with horizontal landing capability. Study guidelines included mission requirements similar to space shuttle, an operational capability begining in 1995, and main propulsion to be advanced hydrogen-fueled rocket engines. Also evaluated was the technical and economic feasibility of this class of SSTO concepts and the comparative features of three operational take-off modes, which were vertical boost, horizontal sled launch, and horizontal take-off with subsequent inflight fueling. Projections of both normal and accelerated technology growth were made. Figures of merit were derived to provide relative rankings of technology areas. The influence of selected accelerated areas on vehicle design and program costs was analyzed by developing near-optimum point designs.

  18. [The first to go--physicians who experimented on themselves].

    PubMed

    Rugstad, Hans Erik

    2005-09-01

    Since ancient times, there have been rules for experiments on humans. Some have claimed that if one thinks an experiment might involve danger, it should first be tried out on oneself. There are, in fact, numerous examples of doctors who have undergone daring experiments on themselves. Among them are Max von Pettenkofer, who drank cholera bacteria, Werner Forssmann who catheterized his own heart, John Paul Stapp, who sat in a rocket sled at almost the speed of sound, and then made an abrupt stop. Doctors from Walter Reed's research team infected themselves with yellow fever, Erik Jacobsen demonstrated the effect of antabuse and alcohol on himself, Barry J. Marshall drank helicobacter pylori bacteria, Klaus Hansen drank heavy water, and Ole Jakob Malm transplanted foreign tissue onto his own skin in order to discern among different tissue types. This article describes these various experiments, why they were done, and their consequences. The perspective of ethics in such experimental research is briefly discussed. PMID:16151505

  19. Design and Factory Test of the E /E- Frascati Linear Accelerator for DAFNE

    SciTech Connect

    Anamkath, H.; Lyons, S.; Nett, D.; Treas, P.; Whitham, K.; Zante, T.; Miller, R.; Boni, R.; Hsieh, H.; Sannibale, F.; Vescovi, M.; Vignola, G.; /Frascati

    2011-11-28

    The electron-positron accelerator for the DAFNE project has been built and is in test at Titan Beta in Dublin, CA. This S-Band RF linac system utilizes four 45 MW sledded klystrons and 16-3 m accelerating structures to achieve the required performance. It delivers a 4 ampere electron beam to the positron converter and accelerates the resulting positrons to 550 MeV. The converter design uses a 4.3T pulsed tapered flux compressor along with a pseudo-adiabatic tapered field to a 5 KG solenoid over the first two positron accelerating sections. Quadrupole focusing is used after 100 MeV. The system performance is given in Table 1. This paper briefly describes the design and development of the various subassemblies in this system and gives the initial factory test data.

  20. Status of Constellation Pressure Garment Development

    NASA Technical Reports Server (NTRS)

    Ross, Amy; Aitchison, Lindsay; Daniel, Brian

    2009-01-01

    The Constellation Program requires the development of a space suit system to meet new requirements for launch, entry, and abort crew survival functions, microgravity intravehicular and extravehicular activities, and lunar surface exploration. This paper summarizes recent work and the current status of the NASA Constellation Space Suit Element Pressure Garment and Crew Survival Subsystem (PG/CS). The emphasis of the work by the PGS/CS team has been in the areas of feasibility studies toward PGS/CS architecture definition, risk mitigation, and requirements development. Included are results from component level engineering studies, testing in the Orion Vehicle and Orion seat mockups, microgravity testing on the Reduced Gravity Aircraft, occupant protection sled testing, analyses and studies, and their implications on Constellation PG/CS subsystem.

  1. Perception of linear acceleration in weightlessness

    NASA Technical Reports Server (NTRS)

    Arrott, Anthony P.; Young, Laurence R.; Merfeld, Daniel M.

    1991-01-01

    Tests of the perception and use of linear acceleration sensory information were performed on the science crews of the Spacelab 1 (SL-1) and D-1 missions using linear 'sleds' in-flight (D-1) and pre-post flight. The time delay between the acceleration step stimulus and the subjective response was consistently reduced during weightlessness, but was neither statistically significant nor of functional importance. Increased variability of responses when going from one environment to the other was apparent from measurements on the first day of the mission and in the first days post-flight. Subjective reports of perceived motion during sinusoidal oscillation in weightlessness were qualitatively similar to reports on earth. In a closed-loop motion nulling task, enhanced performance was observed post-flight in all crewmembers tested in the Y or Z axes.

  2. Perception of linear acceleration in weightlessness

    NASA Technical Reports Server (NTRS)

    Arrott, A. P.; Young, L. R.; Merfeld, D. M.

    1990-01-01

    Tests of the perception and use of linear acceleration sensory information were performed on the science crews of the Spacelab 1 (SL-1) and D-1 missions using linear "sleds" in-flight (D-1) and pre-post flight. The time delay between the acceleration step stimulus and the subjective response was consistently reduced during weightlessness, but was neither statistically significant nor of functional importance. Increased variability of responses when going from one environment to the other was apparent from measurements on the first day of the mission and in the first days post-flight. Subjective reports of perceived motion during sinusoidal oscillation in weightlessness were qualitatively similar to reports on earth. In a closed-loop motion nulling task, enhanced performance was observed post-flight in all crewmembers tested in the Y or Z axes.

  3. Sports Training

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Practitioners of martial arts have long seen a need for a precise method of measuring the power of a karate kick or a boxer's punch in training and competition. Impax sensor is a piezoelectric film less than one thousandth of an inch thick, yet extremely durable. They give out a voltage impulse when struck, the greater the force of impact, the higher the voltage. The impulse is transmitted to a compact electronics package where voltage is translated into a force-pounds reading shown on a digital display. Impax, manufactured by Impulse Technology, Inc. is used by martial arts instructors, practitioners, U.S. Olympic Committee Training Center, football blocking sleds, and boxers as well as police defensive tactics, providing a means of evaluating the performance of recruits.

  4. Measuring aberrations in the rat brain by coherence-gated wavefront sensing using a Linnik interferometer

    PubMed Central

    Wang, Jinyu; Léger, Jean-François; Binding, Jonas; Boccara, A. Claude; Gigan, Sylvain; Bourdieu, Laurent

    2012-01-01

    Aberrations limit the resolution, signal intensity and achievable imaging depth in microscopy. Coherence-gated wavefront sensing (CGWS) allows the fast measurement of aberrations in scattering samples and therefore the implementation of adaptive corrections. However, CGWS has been demonstrated so far only in weakly scattering samples. We designed a new CGWS scheme based on a Linnik interferometer and a SLED light source, which is able to compensate dispersion automatically and can be implemented on any microscope. In the highly scattering rat brain tissue, where multiply scattered photons falling within the temporal gate of the CGWS can no longer be neglected, we have measured known defocus and spherical aberrations up to a depth of 400 µm. PMID:23082292

  5. Improved temperature regulation of APS linac RF components.

    SciTech Connect

    Dortwegt, R.

    1998-09-21

    The temperature of the APS S-Band linac's high-power rf components is regulated by water from individual closed-loop deionized (DI) water systems. The rf components are all made of oxygen-free high-conductivity copper and respond quickly to temperature changes. The SLED cavities are especially temperature-sensitive and cause beam energy instabilities when the temperature is not well regulated. Temperature regulation better than {+-} 0.1 F is required to achieve good energy stability. Improvements in the closed-loop water systems have enabled them to achieve a regulation of {+-} 0.05 F over long periods. Regulation philosophy and equipment are discussed and numerical results are presented.

  6. THE MOLECULAR GAS IN LUMINOUS INFRARED GALAXIES. II. EXTREME PHYSICAL CONDITIONS AND THEIR EFFECTS ON THE X{sub co} FACTOR

    SciTech Connect

    Papadopoulos, Padelis P.; Van der Werf, Paul; Xilouris, E.; Isaak, Kate G.; Gao, Yu E-mail: pvdwerf@strw.leidenuniv.nl E-mail: kisaak@rssd.esa.int

    2012-05-20

    In this work, we conclude the analysis of our CO line survey of luminous infrared galaxies (LIRGs: L{sub IR} {approx}> 10{sup 11} L{sub Sun }) in the local universe (Paper I) by focusing on the influence of their average interstellar medium (ISM) properties on the total molecular gas mass estimates via the so-called X{sub co} = M(H{sub 2})/L{sub co,1-0} factor. One-phase radiative transfer models of the global CO spectral line energy distributions (SLEDs) yield an X{sub co} distribution with (X{sub co}) {approx} (0.6 {+-} 0.2) M{sub Sun} (K km s{sup -1} pc{sup 2}){sup -1} over a significant range of average gas densities, temperatures, and dynamic states. The latter emerges as the most important parameter in determining X{sub co}, with unbound states yielding low values and self-gravitating states yielding the highest ones. Nevertheless, in many (U)LIRGs where available higher-J CO lines (J = 3-2, 4-3, and/or J = 6-5) or HCN line data from the literature allow a separate assessment of the gas mass at high densities ({>=}10{sup 4} cm{sup -3}) rather than a simple one-phase analysis, we find that near-Galactic X{sub co} {approx} (3-6) M{sub Sun} (K km s{sup -1} pc{sup 2}){sup -1} values become possible. We further show that in the highly turbulent molecular gas in ULIRGs, a high-density component will be common and can be massive enough for its high X{sub co} to dominate the average value for the entire galaxy. Using solely low-J CO lines to constrain X{sub co} in such environments (as has been the practice up until now) may have thus resulted in systematic underestimates of molecular gas mass in ULIRGs, as such lines are dominated by a warm, diffuse, and unbound gas phase with low X{sub co} but very little mass. Only well-sampled high-J CO SLEDs (J = 3-2 and higher) and/or multi-J observations of heavy rotor molecules (e.g., HCN) can circumvent such a bias, and the latter type of observations may have actually provided early evidence of it in local ULIRGs. The only

  7. Design and testing of an energy-absorbing crewseat for the F/FB-111 aircraft, volume 1

    NASA Technical Reports Server (NTRS)

    Shane, S. J.

    1985-01-01

    A program to determine if the injury potential could be reduced by replacing the existing crewseats with energy absorbing crewseats is explored. An energy-absorbing test seat was designed using much of the existing seat hardware. An extensive dynamic seat test series, designed to duplicate various crew module ground impact conditions, was conducted at a sled test facility. Comparative tests with operational F-111 crewseats were also conducted. After successful dynamic testing of the seat, more testing was conducted with the seats mounted in an F-111 crew module. Both swing tests and vertical drop tests were conducted. The vertical drop tests were used to obtain comparative data between the energy-absorbing and operational seats. Volume 1 describes the energy absorbing test seat and testing conducted, and evaluates the data from both test series.

  8. The 'W' prawn-trawl with emphasised drag-force transfer to its centre line to reduce overall system drag.

    PubMed

    Balash, Cheslav; Sterling, David; Binns, Jonathan; Thomas, Giles; Bose, Neil

    2015-01-01

    For prawn trawling systems, drag reduction is a high priority as the trawling process is energy intensive. Large benefits have occurred through the use of multiple-net rigs and thin twine in the netting. An additional positive effect of these successful twine-area reduction strategies is the reduced amount of otter board area required to spread the trawl systems, which leads to further drag reduction. The present work investigated the potential of redirecting the drag-strain within a prawn trawl away from the wings and the otter boards to the centre line of the trawl, where top and bottom tongues have been installed, with an aim to minimise the loading/size of the otter boards required to spread the trawl. In the system containing the new 'W' trawl, the drag redirected to the centre-line tongues is transferred forward through a connected sled and towing wires to the trawler. To establish the extent of drag redirection to the centre-line tongues and the relative drag benefits of the new trawl system, conventional and 'W' trawls of 3.65 m headline length were tested firstly over a range of spread ratios in the flume tank, and subsequently at optimum spread ratio in the field. The developed 'W' trawl effectively directed 64% of netting-drag off the wings and onto the centre tongues, which resulted in drag savings in the field of ∼20% for the associated 'W' trawl/otter-board/sled system compared to the traditional trawl/otter-board arrangement in a single trawl or twin rig configuration. Furthermore, based on previously published data, the new trawl when used in a twin rig system is expected to provide approximately 12% drag reduction compared to quad rig. The twin 'W' trawl system also has benefits over quad rig in that a reduced number of cod-end/By-catch Reduction Device units need to be installed and attended each tow. PMID:25751251

  9. WARM MOLECULAR GAS IN LUMINOUS INFRARED GALAXIES

    SciTech Connect

    Lu, N.; Zhao, Y.; Xu, C. K.; Mazzarella, J. M.; Howell, J.; Appleton, P.; Lord, S.; Schulz, B.; Gao, Y.; Armus, L.; Díaz-Santos, T.; Surace, J.; Isaak, K. G.; Petric, A. O.; Charmandaris, V.; Evans, A. S.; Inami, H.; Iwasawa, K.; Leech, J.; Sanders, D. B.; and others

    2014-06-01

    We present our initial results on the CO rotational spectral line energy distribution (SLED) of the J to J–1 transitions from J = 4 up to 13 from Herschel SPIRE spectroscopic observations of 65 luminous infrared galaxies (LIRGs) in the Great Observatories All-Sky LIRG Survey. The observed SLEDs change on average from one peaking at J ≤ 4 to a broad distribution peaking around J ∼ 6 to 7 as the IRAS 60-to-100 μm color, C(60/100), increases. However, the ratios of a CO line luminosity to the total infrared luminosity, L {sub IR}, show the smallest variation for J around 6 or 7. This suggests that, for most LIRGs, ongoing star formation (SF) is also responsible for a warm gas component that emits CO lines primarily in the mid-J regime (5 ≲ J ≲ 10). As a result, the logarithmic ratios of the CO line luminosity summed over CO (5–4), (6–5), (7–6), (8–7) and (10–9) transitions to L {sub IR}, log R {sub midCO}, remain largely independent of C(60/100), and show a mean value of –4.13 (≡log R{sub midCO}{sup SF}) and a sample standard deviation of only 0.10 for the SF-dominated galaxies. Including additional galaxies from the literature, we show, albeit with a small number of cases, the possibility that galaxies, which bear powerful interstellar shocks unrelated to the current SF, and galaxies, in which an energetic active galactic nucleus contributes significantly to the bolometric luminosity, have their R {sub midCO} higher and lower than R{sub midCO}{sup SF}, respectively.

  10. Wheelchair integrated occupant restraints: feasibility in frontal impact.

    PubMed

    VanRoosmalen, L; Bertocci, G E; Ha, D; Karg, P

    2001-12-01

    Individuals often use their wheelchair as a motor vehicle seat when traveling in motor vehicles. The current use of fixed vehicle-mounted wheelchair occupant restraint systems (FWORSs) often results in poor belt fit and discomfort. Additionally, satisfaction, usability and usage rate of FWORSs during transit use are often low. The automotive industry has shown improved occupant restraint usage, belt fit and injury protection when integrating the upper torso and pelvic restraint in a motor vehicle seat. This study compared occupant injury measures of a FWORS to a concept wheelchair integrated restraint system (WIRS) using a 20g frontal sled impact test with a 30 mph change in velocity. Neck loads, neck moments, head, pelvis and chest acceleration, sternum compression and knee and head excursion data were recorded from the wheelchair seated 50th percentile male hybrid III anthropomorphic test dummy (ATD). The WIRS resulted in a lower head injury criteria (HIC) value, lower sternum compression and a lower upper-torso restraint load than the FWORS. Compared with the FWORS, increased head, knee and wheelchair excursions and higher neck loads and moments were measured in the WIRS test. Both restraint scenario injury parameters were complied with occupant injury criteria based on General Motors Injury Assessment Reference Values (GM-IARVs) and occupant kinematic requirements defined by the Society of Automotive Engineers (SAE) voluntary standard, J2249. A higher motion criteria index was calculated for the WIRS scenario and a comparable combined injury criteria index was calculated for both restraint scenarios. The sled impact test showed WIRS concept feasibility, facilitating further development by industrial manufacturers who might further want to pursue this restraint principle to increase wheelchair occupant safety and comfort during transport in motor vehicles. PMID:11801410

  11. Echinococcus canadensis transmission in the North.

    PubMed

    Oksanen, Antti; Lavikainen, Antti

    2015-10-30

    The Echinococcus granulosus complex (EG) is the causative agent of cystic echinococcosis (CE). Northern cervid Echinococcus was previously suggested to be the ancestor of the entire EG. During the last century, it was regarded to have three (or four) different, but often overlapping, transmission cycles in the circumpolar North: the original wolf-wild cervid (reindeer or elk)-cycle; the semi-synanthropic cycle involving sled and hunting dogs and wild cervids; and the synanthropic cycle involving herding dogs and semi-domesticated reindeer. Human infections mainly derived from the latter two cycles. In Fennoscandia, the synanthropic cycle has been eliminated during the last 50 years due to changes in reindeer husbandry methods; machinery making herding dogs largely redundant. Typical to human CE in the North has been the relatively benign nature of the disease compared with CE caused by E. granulosus sensu stricto. The metacestodes in humans and in the natural cervid hosts predominantly appear in the lungs. The causative agents have been identified as EG mitochondrial genotypes G8 and G10, now together with G6 (camel), G7 (pig) and G9 genotypes constituting the Echinococcus canadensis species. Based on recent findings in reindeer in Yakutia, G6 might also be recognised among cervid genotypes. The geographical distribution of both G8 and G10 is circumpolar, with G10 currently apparently more prevalent both in the Palearctic and Nearctic. Because of the disappearance of the working dog, E. canadensis in Fennoscandia is again highly dependent on the wolf, as it was before domestication of the dog. Pet and sled dogs, if their number further increases, may to a minor part participate in the life cycle. Human CE in the North was mostly diagnosed by mass chest tuberculosis radiography campaigns, which have been discontinued. PMID:26264249

  12. The Effect of Upper Body Mass and Initial Knee Flexion on the Injury Outcome of Post Mortem Human Subject Pedestrian Isolated Legs.

    PubMed

    Petit, Philippe; Trosseille, Xavier; Dufaure, Nicolas; Dubois, Denis; Potier, Pascal; Vallancien, Guy

    2014-11-01

    In the ECE 127 Regulation on pedestrian leg protection, as well as in the Euro NCAP test protocol, a legform impactor hits the vehicle at the speed of 40 kph. In these tests, the knee is fully extended and the leg is not coupled to the upper body. However, the typical configuration of a pedestrian impact differs since the knee is flexed during most of the gait cycle and the hip joint applies an unknown force to the femur. This study aimed at investigating the influence of the inertia of the upper body (modelled using an upper body mass fixed at the proximal end of the femur) and the initial knee flexion angle on the lower limb injury outcome. In total, 18 tests were conducted on 18 legs from 9 Post Mortem Human Subjects (PMHS). The principle of these tests was to impact the leg at 40 kph using a sled equipped with 3 crushing steel tubes, the stiffness of which were representative of the front face of a European sedan (bonnet leading edge, bumper and spoiler). The mass of the equipped sled was 74.5 kg. The test matrix was designed to perform 4 tests in 4 configurations combining two upper body masses (either 0 or 3 kg) and two knee angles (0 or 20 degrees) at 40 kph (11 m/s) plus 2 tests at 9 m/s. Autopsies were performed on the lower limbs and an injury assessment was established. The findings of this study were first that the increase of the upper body mass resulted in more severe injuries, second that an initial flexion of the knee, corresponding to its natural position during the gait cycle, decreased the severity of the injuries, and third that based on the injury outcome, a test conducted with no upper body mass and the knee fully extended was as severe as a test conducted with a 3 kg upper body mass and an initial knee flexion of 20°. PMID:26192955

  13. Experimental Study of the Richtmyer-Meshkov Instability of Incompressible Fluids

    NASA Technical Reports Server (NTRS)

    Niederhaus, Charles; Jacobs, Jeffrey W.

    2002-01-01

    The Richtmyer-Meshkov instability of a low Atwood number, miscible, two-liquid system is investigated experimentally. The initially stratified fluids are contained within a rectangular tank mounted to a sled that rides on a vertical set of rails. The instability is generated by dropping the sled onto a coil spring, producing a nearly impulsive upward acceleration. The subsequent freefall that occurs as the container travels upward and then downward on the rails allows the instability to evolve in the absence of gravity. The interface separating the two liquids initially has a well-defined, sinusoidal perturbation that quickly inverts and then grows in amplitude after undergoing the impulsive acceleration. Disturbance amplitudes are measured and compared to theoretical predictions. Linear stability theory gives excellent agreement with the measured initial growth rate, a(sub 0), for single-mode perturbations with the predicted amplitudes differing by less than 10% from experimental measurements up to a nondimensional time ka(sub 0)t = 0.7, where k is the wavenumber. Linear stability theory also provides excellent agreement for the individual mode amplitudes of multi-mode initial perturbations up until the interface becomes multi-valued. Comparison with previously published weakly nonlinear single-mode models shows good agreement up to ka(sub 0)t = 3, while published nonlinear single-mode models provide good agreement up to ka(sub 0)t = 30. The effects of Reynolds number on the vortex core evolution and overall growth rate of the interface are also investigated. Measurements of the overall amplitude are found to be unaffected by the Reynolds number for the range of values studied here. However, experiments carried out at lower values of Reynolds numbers were found to have decreased vortex core rotation rates. In addition, an instability in the vortex cores is observed.

  14. Thoracic injury metrics with side airbag: Stationary and dynamic occupants

    PubMed Central

    Hallman, Jason J; Yoganandan, N; Pintar, Frank A

    2010-01-01

    Objective Injury risk from side airbag deployment has been assessed using stationary out-of-position occupant test protocols. However, stationary conditions may not always represent real world environments. Therefore, the objective of the present study was to evaluate the effects of torso side airbag deployment on close-proximity occupants, comparing a stationary test protocol with dynamic sled conditions. Methods Chest compression and viscous metrics were quantified from sled tests utilizing post-mortem human specimens and computational simulations with three boundary conditions: rigid wall, ideal airbag interaction, and close-proximity airbag deployment. PMHS metrics were quantified from chestband contour reconstructions. The parametric effect of ΔV on close-proximity occupant was examined with the computational model. Results PMHS injuries suggested close-proximity occupants may sustain visceral trauma, which was not observed in occupants subjected to rigid wall or ideal airbag boundary conditions. Peak injury metrics were also elevated with close-proximity occupant relative to other boundary conditions. The computational model indicated decreasing influence of airbag on compression metrics with increasing ΔV. Airbag influence on viscous metric was greatest with close-proximity occupant at ΔV = 7.0 m/s, at which the response magnitude was greater than linear summation of metrics resulting from rigid impact and stationary close-proximity interaction. Conclusions These results suggest that stationary close-proximity occupants may not represent the only scenario of side airbag deployment harmful to the thoracoabdominal region. The sensitivity of the viscous metric and implications for visceral trauma are also discussed. PMID:20730691

  15. Online X-ray Fluorescence (XRF) Analysis of Heavy Metals in Pulverized Coal on a Conveyor Belt.

    PubMed

    Yan, Zhang; XinLei, Zhang; WenBao, Jia; Qing, Shan; YongSheng, Ling; DaQian, Hei; Da, Chen

    2016-02-01

    Heavy metals in haze episode will continue to threaten the quality of public health around the world. In order to decrease the emission of heavy metals produced from coal burning, an online X-ray fluorescence (XRF) analyzer system, consisting of an XRF analyzer with data acquisition software and a laser rangefinder, was developed to carry out the measurement of heavy metals in pulverized coal. The XRF analyzer was mounted on a sled, which can effectively smooth the surface of pulverized coal and reduce the impact of surface roughness during online measurement. The laser rangefinder was mounted over the sled for measuring the distance between a pulverized coal sample and the analyzer. Several heavy metals and other elements in pulverized coal were online measured by the XRF analyzer directly above a conveyor belt. The limits of detection for Hg, Pb, Cr, Ti, Fe, and Ca by the analyzer were 44 ± 2, 34 ± 2, 17 ± 3, 41 ± 4, 19 ± 3, and 65 ± 2 mg·kg(-1), respectively. The relative standard deviation (%RSD) for the elements mentioned was less than 7.74%. By comparison with the results by inductively-coupled plasma mass spectrometry (ICP-MS), relative deviation (%D) of the online XRF analyzer was less than 10% for Cr, Ti, and Ca, in the range of 0.8-24.26% for Fe, and greater than 20% for Hg and Pb. PMID:26787706

  16. Tilt perception during dynamic linear acceleration.

    PubMed

    Seidman, S H; Telford, L; Paige, G D

    1998-04-01

    Head tilt is a rotation of the head relative to gravity, as exemplified by head roll or pitch from the natural upright orientation. Tilt stimulates both the otolith organs, owing to shifts in gravitational orientation, and the semicircular canals in response to head rotation, which in turn drive a variety of behavioral and perceptual responses. Studies of tilt perception typically have not adequately isolated otolith and canal inputs or their dynamic contributions. True tilt cannot readily dissociate otolith from canal influences. Alternatively, centrifugation generates centripetal accelerations that simulate tilt, but still entails a rotatory (canal) stimulus during important periods of the stimulus profiles. We reevaluated the perception of head tilt in humans, but limited the stimulus to linear forces alone, thus isolating the influence of otolith inputs. This was accomplished by employing a centrifugation technique with a variable-radius spinning sled. This allowed us to accelerate the sled to a constant angular velocity (128 degrees/s), with the subject centered, and then apply dynamic centripetal accelerations after all rotatory perceptions were extinguished. These stimuli were presented in the subjects' naso-occipital axis by translating the subjects 50 cm eccentrically either forward or backward. Centripetal accelerations were thus induced (0.25 g), which combined with gravity to yield a dynamically shifting gravitoinertial force simulating pitch-tilt, but without actually rotating the head. A magnitude-estimation task was employed to characterize the dynamic perception of pitch-tilt. Tilt perception responded sluggishly to linear acceleration, typically reaching a peak after 10-30 s. Tilt perception also displayed an adaptation phenomenon. Adaptation was manifested as a per-stimulus decline in perceived tilt during prolonged stimulation and a reversal aftereffect upon return to zero acceleration (i.e., recentering the subject). We conclude that otolith

  17. OT1_nlu_1: Herschel Spectroscopic Survey of Warm Molecular Gas in Local Luminous Infrared Galaxies

    NASA Astrophysics Data System (ADS)

    Lu, N.

    2010-07-01

    We propose to survey CO spectral line energy distribution (SLED), from J=4-3 up to J=13-12, on 93 local luminous infrared galaxies (LIRGs; L_{IR} > 1.0E11 L_{sun}) with Herschel SPIRE FTS spectrometer. These galaxies, plus 32 additional LIRGs that will have similar data from existing Herschel programs (mainly the HerCULES project), form a flux-limited subset of the Great Observatories All-Sky LIRGs Survey (GOALS) sample. Our proposal is built on the legacy of GOALS and extends beyond the existing Herschel HerCULES program, which emphasizes more on ULIRGs, to a much needed sample coverage of the more numerous and diverse population of less luminous LIRGs. The data from the proposed observations will not only provide much needed local LIRG templates for future ALMA studies of high-redshift counterparts, but also lend us a powerful diagnostic tool to probe the warm and dense molecular gas that are more closely related to the starburst or AGN activity in the nuclei of LIRGs. The data from this proposal will provide important statistical clues to the interplay between the cold and warm molecular gas, IR luminosity, star formation rate and efficiency, and the diverse properties of LIRGs. Specifically, using the homogeneous CO SLED data from this proposal, together with ground-base, low-order CO line data (mainly J=1-0) and other data that have been compiled for the GOALS sample, we will address the following questions: (1) What is the dominant nuclear power source in individual sample galaxy: starburst or AGN? (2) What are the typical physical properties of warm molecular gas in the nuclei of LIRGs? (3) How do the nuclear warm gas components correlate to the cold gas component, star formation rate and efficiency, dust temperature, etc? and (4) How does molecular gas excitation change along a merger sequence?

  18. Predicting the intensity mapping signal for multi-J CO lines

    NASA Astrophysics Data System (ADS)

    Mashian, Natalie; Sternberg, Amiel; Loeb, Abraham

    2015-11-01

    We present a novel approach to estimating the intensity mapping signal of any CO rotational line emitted during the Epoch of Reionization (EoR). Our approach is based on large velocity gradient (LVG) modeling, a radiative transfer modeling technique that generates the full CO spectral line energy distribution (SLED) for a specified gas kinetic temperature, volume density, velocity gradient, molecular abundance, and column density. These parameters, which drive the physics of CO transitions and ultimately dictate the shape and amplitude of the CO SLED, can be linked to the global properties of the host galaxy, mainly the star formation rate (SFR) and the SFR surface density. By further employing an empirically derived SFR-M relation for high redshift galaxies, we can express the LVG parameters, and thus the specific intensity of any CO rotational transition, as functions of the host halo mass M and redshift z. Integrating over the range of halo masses expected to host CO-luminous galaxies, we predict a mean CO(1-0) brightness temperature ranging from ~ 0.6 μK at z = 6 to ~ 0.03 μK at z = 10 with brightness temperature fluctuations of ΔCO2 ~ 0.1 and 0.005 μK respectively, at k = 0.1 Mpc-1. In this model, the CO emission signal remains strong for higher rotational levels at z = 6, with langle TCO rangle ~ 0.3 and 0.05 μK for the CO J = 6arrow5 and CO J = 10arrow9 transitions respectively. Including the effects of CO photodissociation in these molecular clouds, especially at low metallicities, results in the overall reduction in the amplitude of the CO signal, with the low- and high-J lines weakening by 2-20% and 10-45%, respectively, over the redshift range 4 < z < 10.

  19. First CO J = 6-5 and J = 4-3 Detections in Local ULIRGs: The Dense Gas in Markarian 231 and Its Cooling Budget

    NASA Astrophysics Data System (ADS)

    Papadopoulos, Padeli P.; Isaak, Kate G.; van der Werf, Paul P.

    2007-10-01

    We report on detections of the high-excitation CO J=6-5 and J=4-3 lines in Mrk 231, a prototypical ultraluminous infrared galaxy (ULIRG) and Seyfert 1 QSO. These observations are combined with CO J=3-2 and HCN J=4-3 measurements from this work and CO J=2-1, CO J=1-0, 13CO J=2-1, and HCN J=1-0 measurements taken from the literature to provide better constraints on the properties of the molecular gas in an extreme starburst/QSO in the local universe. We find that the CO J=4-3 and J=6-5 transitions trace a different gas phase from that dominating the lower three CO transitions, with n(H2)~(1-3)×104 cm-3 and Tk~40-70 K. This phase is responsible for the luminous HCN emission and contains most of the H2 gas mass of this galaxy. The total CO line cooling emanating from this dense phase is found similar to that of the [C II] line at 158 μm, suggesting a very different thermal balance to that seen in lower IR luminosity galaxies, and one likely dominated by dense photon-dominated regions. Our dense ``sampling'' of the CO rotational ladder and the HCN lines enables us to produce well-constrained spectral line energy distributions (SLEDs) for the dense molecular gas in Mrk 231 and compare them to those of high-redshift starbursts, many of which have SLEDs that may be affected by strong lensing. Finally, we use our local molecular line excitation template to assess the capabilities of future centimeter and millimeter/submillimeter arrays in detecting CO and HCN transitions in similar systems throughout the local and distant universe.

  20. CO Line Emission from Compact Nuclear Starburst Disks around Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Armour, J. N.; Ballantyne, D. R.

    2012-06-01

    There is substantial evidence for a connection between star formation in the nuclear region of a galaxy and growth of the central supermassive black hole. Furthermore, starburst activity in the region around an active galactic nucleus (AGN) may provide the obscuration required by the unified model of AGNs. Molecular line emission is one of the best observational avenues to detect and characterize dense, star-forming gas in galactic nuclei over a range of redshift. This paper presents predictions for the carbon monoxide (CO) line features from models of nuclear starburst disks around AGNs. These small-scale (lsim 100 pc), dense and hot starbursts have CO luminosities similar to scaled-down ultra-luminous infrared galaxies and quasar host galaxies. Nuclear starburst disks that exhibit a pc-scale starburst and could potentially act as the obscuring torus show more efficient CO excitation and higher brightness temperature ratios than those without such a compact starburst. In addition, the compact starburst models predict strong absorption when J Upper >~ 10, a unique observational signature of these objects. These findings allow for the possibility that CO spectral line energy distributions (SLEDs) could be used to determine if starburst disks are responsible for the obscuration in z <~ 1 AGNs. Directly isolating the nuclear CO line emission of such compact regions around AGNs from galactic-scale emission will require high-resolution imaging or selecting AGN host galaxies with weak galactic-scale star formation. Stacking individual CO SLEDs will also be useful in detecting the predicted high-J features.

  1. Warm Molecular Gas in Luminous Infrared Galaxies

    NASA Astrophysics Data System (ADS)

    Lu, N.; Zhao, Y.; Xu, C. K.; Gao, Y.; Armus, L.; Mazzarella, J. M.; Isaak, K. G.; Petric, A. O.; Charmandaris, V.; Díaz-Santos, T.; Evans, A. S.; Howell, J.; Appleton, P.; Inami, H.; Iwasawa, K.; Leech, J.; Lord, S.; Sanders, D. B.; Schulz, B.; Surace, J.; van der Werf, P. P.

    2014-06-01

    We present our initial results on the CO rotational spectral line energy distribution (SLED) of the J to J-1 transitions from J = 4 up to 13 from Herschel SPIRE spectroscopic observations of 65 luminous infrared galaxies (LIRGs) in the Great Observatories All-Sky LIRG Survey. The observed SLEDs change on average from one peaking at J <= 4 to a broad distribution peaking around J ~ 6 to 7 as the IRAS 60-to-100 μm color, C(60/100), increases. However, the ratios of a CO line luminosity to the total infrared luminosity, L IR, show the smallest variation for J around 6 or 7. This suggests that, for most LIRGs, ongoing star formation (SF) is also responsible for a warm gas component that emits CO lines primarily in the mid-J regime (5 <~ J <~ 10). As a result, the logarithmic ratios of the CO line luminosity summed over CO (5-4), (6-5), (7-6), (8-7) and (10-9) transitions to L IR, log R midCO, remain largely independent of C(60/100), and show a mean value of -4.13 (\\equiv log R^SF_midCO) and a sample standard deviation of only 0.10 for the SF-dominated galaxies. Including additional galaxies from the literature, we show, albeit with a small number of cases, the possibility that galaxies, which bear powerful interstellar shocks unrelated to the current SF, and galaxies, in which an energetic active galactic nucleus contributes significantly to the bolometric luminosity, have their R midCO higher and lower than R^SF_midCO, respectively. Based on Herschel observations. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

  2. Parachute Compartment Drop Test Vehicle for Testing the Crew Exploration Vehicle's Parachute Assembly System

    NASA Technical Reports Server (NTRS)

    Lubey, Daniel P.; Thiele, Sara R.; Gruseck, Madelyn L.; Evans, Carol T.

    2010-01-01

    Though getting astronauts safely into orbit and beyond has long been one of NASA?s chief goals, their safe return has always been equally as important. The Crew Exploration Vehicle?s (CEV) Parachute Assembly System (CPAS) is designed to safely return astronauts to Earth on the next-generation manned spacecraft Orion. As one means for validating this system?s requirements and testing its functionality, a test article known as the Parachute Compartment Drop Test Vehicle (PC-DTV) will carry a fully-loaded yet truncated CPAS Parachute Compartment (PC) in a series of drop tests. Two aerodynamic profiles for the PC-DTV currently exist, though both share the same interior structure, and both have an Orion-representative weight of 20,800 lbf. Two extraction methods have been developed as well. The first (Cradle Monorail System 2 - CMS2) uses a sliding rail technique to release the PC-DTV midair, and the second (Modified DTV Sled; MDS) features a much less constrained separation method though slightly more complex. The decision as to which aerodynamic profile and extraction method to use is still not finalized. Additional CFD and stress analysis must be undertaken in order to determine the more desirable options, though at present the "boat tail" profile and the CMS2 extraction method seem to be the favored options in their respective categories. Fabrication of the PC-DTV and the selected extraction sled is set to begin in early October 2010 with an anticipated first drop test in mid-March 2011.

  3. Multiple case studies of STEM teachers' orientations to science teaching through engineering design

    NASA Astrophysics Data System (ADS)

    Rupp, Madeline

    The following master's thesis is composed of two manuscripts describing STEM teachers' orientations to science teaching through engineering within the context of the Science Learning through Engineering Design (SLED) partnership. The framework guiding both studies was science teaching orientations, a component of pedagogical content knowledge. Data were collected via semi-structured interviews, multi-day classroom observations, pre- and post-observation interviews, implementation plans, and written reflections. Data sources were analyzed to generate two orientations to science teaching through engineering design for each participant. The first manuscript illustrates a single case study conducted with a sixth grade STEM teacher. Results of this study revealed a detailed picture of the teacher's goals, practices, assessments, and general views when teaching science through engineering design. Common themes across the teacher's instruction were used to characterize her orientations to science teaching through engineering design. Overall, the teacher's orientations showed a shift in her practice from didactic to student-centered methods of teaching as a result of integrating engineering design-based curriculum. The second manuscript describes a comparative case study of two sixth grade SLED participants. Results of this study revealed more complex and diverse relationships between the teachers' orientations to teaching science through engineering design and their instruction. Participants' orientations served as filters for instruction, guided by their divergent purposes for science teaching. Furthermore, their orientations and resulting implementation were developed from knowledge gained in teacher education, implying that teacher educators and researchers can use this framework to learn more about how teachers' knowledge is used to integrate engineering and science practices in the K-12 classroom.

  4. Evaluation of Mid-Size Male Hybrid III Models for use in Spaceflight Occupant Protection Analysis

    NASA Technical Reports Server (NTRS)

    Putnam, Jacob B.; Sommers, Jeffrey T.; Wells, Jessica A.; Newby, Nathaniel J.; Currie-Gregg, Nancy J.; Lawrence, Chuck

    2016-01-01

    In an effort to improve occupant safety during dynamic phases of spaceflight, the National Aeronautics and Space Administration (NASA) has worked to develop occupant protection standards for future crewed spacecraft. One key aspect of these standards is the identification of injury mechanisms through anthropometric test devices (ATDs). Within this analysis, both physical and computational ATD evaluations are required to reasonably encompass the vast range of loading conditions any spaceflight crew may encounter. In this study the accuracy of publically available mid-size male HIII ATD finite element (FE) models are evaluated within applicable loading conditions against extensive sled testing performed on their physical counterparts. Methods: A series of sled tests were performed at the Wright Patterson Air force Base (WPAFB) employing variations of magnitude, duration, and impact direction to encompass the dynamic loading range for expected spaceflight. FE simulations were developed to the specifications of the test setup and driven using measured acceleration profiles. Both fast and detailed FE models of the mid-size male HIII were ran to quantify differences in their accuracy and thus assess the applicability of each within this field. Results: Preliminary results identify the dependence of model accuracy on loading direction, magnitude, and rate. Additionally the accuracy of individual response metrics are shown to vary across each model within evaluated test conditions. Causes for model inaccuracy are identified based on the observed relationships. Discussion: Computational modeling provides an essential component to ATD injury metric evaluation used to ensure the safety of future spaceflight occupants. The assessment of current ATD models lays the groundwork for how these models can be used appropriately in the future. Identification of limitations and possible paths for improvement aid in the development of these effective analysis tools.

  5. Reaction of a human head/neck/torso system to shock.

    PubMed

    Luo, Z P; Goldsmith, W

    1991-01-01

    The purpose of this study is to predict human response to, and potential damage from, impact loading by using numerical and physical models to monitor the head and thoracic reactions, intervertebral disk pressures, muscle elongations, and some internal organ pressures. The numerical model consists of a three-dimensional lumped-parameter system of ten rigid bodies connected by nine intervertebral joints and 28 muscle pairs. The masses represent the head; cervical vertebrae C1-C2, C3-C4, C5-C6, C7-T1 (the first thoracic vertebra); the entire thorax; lumbar vertebrae L1-L2, L3, L4-L5; and the pelvis. The physical model consists of: a water-filled cadaver skull, held in position by attached ligaments; plastic skeletal components involving vertebrae, sternum, ribs and pelvis; silicon rubber intervertebral disks; fabric muscles and ligaments; and water-filled containers replicating the liver, spleen and kidneys. The pelvis of the model is affixed to a plate mounted on a sled that runs on a track. Loading is applied by deceleration from a given velocity that occurs due to the impact of the sled with a fixed aluminum block. Results from the numerical model are compared with corresponding experimental information from the physical structure. Good correlation was obtained in these comparisons up to about 200-250 ms after impact. The results indicate that the head, cervical muscles and disks in the lumbar region are subjected to the greatest force changes and thus are most likely to be injured. PMID:1880135

  6. Water Vapor in nearby Infrared Galaxies as Probed by Herschel

    NASA Astrophysics Data System (ADS)

    Yang, Chentao; Gao, Yu; Omont, A.; Liu, Daizhong; Isaak, K. G.; Downes, D.; van der Werf, P. P.; Lu, Nanyao

    2013-07-01

    We report the first systematic study of the submillimeter water vapor rotational emission lines in infrared (IR) galaxies based on the Fourier Transform Spectrometer (FTS) data of Herschel SPIRE. Among the 176 galaxies with publicly available FTS data, 45 have at least one H2O emission line detected. The H2O line luminosities range from ~1 × 105 L ⊙ to ~5 × 107 L ⊙ while the total IR luminosities (L IR) have a similar spread (~1-300 × 1010 L ⊙). In addition, emission lines of H2O+ and H_2^{18}O are also detected. H2O is found, for most galaxies, to be the strongest molecular emitter after CO in FTS spectra. The luminosity of the five most important H2O lines is near-linearly correlated with L IR, regardless of whether or not strong active galactic nucleus signature is present. However, the luminosity of H2O(211-202) and H2O(220-211) appears to increase slightly faster than linear with L IR. Although the slope turns out to be slightly steeper when z ~ 2-4 ULIRGs are included, the correlation is still closely linear. We find that L_{H_2O}/L IR decreases with increasing f 25/f 60, but see no dependence on f 60/f 100, possibly indicating that very warm dust contributes little to the excitation of the submillimeter H2O lines. The average spectral line energy distribution (SLED) of the entire sample is consistent with individual SLEDs and the IR pumping plus collisional excitation model, showing that the strongest lines are H2O(202-111) and H2O(321-312). Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

  7. Field Micrometeorological Measurements, Process-Level Studies and Modeling of Methane and Carbon Dioxide Fluxes in a Boreal Wetland Ecosystem

    NASA Technical Reports Server (NTRS)

    Verma, S. B.; Arkebauer, T. J.; Ullman, F. G.; Valentine, D. W.; Parton, W. J.; Schimel, D. S.

    1998-01-01

    The main instrumentation platform consisted of eddy correlation sensors mounted on a scaffold tower at a height of 4.2 m above the peat surface. The sensors were attached to a boom assembly which could be rotated into the prevailing winds. The boom assembly was mounted on a movable sled which, when extended, allowed sensors to be up to 2 m away from the scaffolding structure to minimize flow distortion. When retracted, the sensors could easily be installed, serviced or rotated. An electronic level with linear actuators allowed the sensors to be remotely levelled once the sled was extended. Two instrument arrays were installed. A primary (fast-response) array consisted of a three-dimensional sonic anemometer, a methane sensor (tunable diode laser spectrometer), a carbon dioxide/water vapor sensor, a fine wire thermocouple and a backup one-dimensional sonic anemometer. The secondary array consisted of a one-dimensional sonic anemometer, a fine wire thermocouple and a Krypton hygrometer. Descriptions of these sensors may be found in other reports (e.g., Verma; Suyker and Verma). Slow-response sensors provided supporting measurements including mean air temperature and humidity, mean horizontal windspeed and direction, incoming and reflected solar radiation, net radiation, incoming and reflected photosynthetically active radiation (PAR), soil heat flux, peat temperature, water-table elevation and precipitation. A data acquisition system (consisting of an IBM compatible microcomputer, amplifiers and a 16 bit analog-to-digital converter), housed in a small trailer, was used to record the fast response signals. These signals were low-pass filtered (using 8-pole Butterworth active filters with a 12.5 Hz cutoff frequency) and sampled at 25 Hz. Slow-response signals were sampled every 5 s using a network of CR21X (Campbell Scientific, Inc., Logan Utah) data loggers installed in the fen. All signals were averaged over 30-minute periods (runs).

  8. The characteristics of the outdoor school environment associated with physical activity

    PubMed Central

    Haug, Ellen; Torsheim, Torbjørn; Sallis, James F.; Samdal, Oddrun

    2010-01-01

    The school is an important setting for physical activity. The purpose of the present study was to examine the association between physical environmental characteristics and participation in daily physical activity during school breaks. Data from 130 schools and 16 471 students (Grades 4–10) in Norway were obtained in 2004 through self-administered questionnaires to principals and students. Multilevel logistic regression models revealed that boys at secondary level with a larger number of outdoor facilities at school had 2.69 times [95% confidence interval (CI) = 1.21–5.98] and girls 2.90 times (95% CI = 1.32–6.37) higher odds of being physically active compared with students in schools with fewer facilities. Boys at secondary level with areas for hopscotch/skipping rope had 2.53 times (95% CI = 1.55–4.13), with a soccer field 1.68 times (95% CI = 1.15–2.45), with playground equipment 1.66 times (95% CI = 1.16–2.37) and with a sledding hill 1.70 times (95% CI = 1.23–2.35) higher odds to be physically active compared with students in schools without these facilities. A sledding hill was also associated with girls’ physical activity participation in secondary school (odds ratio = 1.58, 95% CI = 1.11–2.24). Outdoor facilities in secondary schools are associated with students’ daily physical activity participation during school breaks. Therefore, improving the outdoor environment should be considered in physical activity promotion school programs in secondary schools. PMID:18936270

  9. Evaluation of the hybrid III and Q-series pediatric ATD upper neck loads as compared to pediatric volunteers in low-speed frontal crashes.

    PubMed

    Seacrist, Thomas; Mathews, Emily A; Balasubramanian, Sriram; Maltese, Matthew R; Arbogast, Kristy B

    2013-11-01

    Debate exists in the automotive community regarding the validity of the pediatric ATD neck response and corresponding neck loads. Previous research has shown that the pediatric ATDs exhibit hyper-flexion and chin-to-chest contact resulting in overestimations of neck loads and neck injury criteria. Our previous work comparing the kinematics of the Hybrid III and Q-series 6 and 10-year-old ATDs to pediatric volunteers in low-speed frontal sled tests revealed decreased ATD cervical and thoracic spine excursions. These kinematic differences may contribute to the overestimation of upper neck loads by the ATD. The current study compared upper neck loads of the Hybrid III and Q-series 6 and 10-year-old ATDs against size-matched male pediatric volunteers in low-speed frontal sled tests. A 3-D near-infrared target tracking system quantified the position of markers on the ATD and pediatric volunteers (head top, nasion, bilateral external auditory meatus). Shear force (F x ), axial force (F z ), bending moment (M y ), and head angular acceleration ([Formula: see text]) were calculated about the upper neck using standard equations of motion. In general, the ATDs underestimated axial force and overestimated bending moment compared to the human volunteers. The Hybrid III 6, Q6, and Q10 exhibited reduced head angular acceleration and modest increases in upper neck shear compared to the pediatric volunteers. The reduction in axial force and bending moment has important implications for neck injury predictions as both are used when calculating N ij . These analyses provide insight into the biofidelity of the pediatric ATD upper neck loads in low-speed crash environments. PMID:23780472

  10. Effects of rectilinear acceleration, caloric and optokinetic stimulation of human subjects in the Spacelab D-1 mission

    NASA Astrophysics Data System (ADS)

    Wetzig, J.; von Baumgarten, R.

    A set of vestibular experiments was performed during the course of the German Spacelab D-1 mission from 30 October to 6 November 1985 by a consortium of experimenters from various european countries. Similar to the Spacelab SL-1 mission all of the scientific crew members were theoretically and practically trained for the experiments. Baseline measurements for all tests were collected 113, 86, 44, 30 and 18 days prior to the mission and compared with data taken inflight, on the landing day and the consecutive 7 to 14 days. The hardware comprised mainly a motordriven accelerating platform, the SPACE SLED, and the vestibular helmet, a multi-purpose instrument in support of a variety of vestibular experiments including air-calorisation of the ears, optokinetic stimulation pattern presentation and optical and nystagmographic recording of eye movements. Measurements of the threshold for the perception of detection of whole body movement did not reveal any dramatic changes in the 2 measured axes inflight when compared to preflight values. Early postflight values show a significantly elevated threshold for all axes in 3 out of 4 subjects. The caloric nystagmus, already found during the SL-1 mission, was confirmed on all three tested subjects during the D-1 mission. It's amplitude and in some instances it's direction were influenced by horizontal acceleration on the SLED. The amplitude of optokinetic nystagmus increased when subjects were allowed to free-float over that seen when subjects were fixed. Stimulation of the neck receptors by roll movements of the body against the fixated head resulted in illusory object motion to the contralateral side. Torsional movements of the eyes during such neck receptor stimulation was present inflight and postflight, while it had not been observed preflight. Most results point to a reduction of otolithic effects in favour of visual and proprioceptive influences for spatial orientation.

  11. Decisions in motion: vestibular contributions to saccadic target selection.

    PubMed

    Rincon-Gonzalez, L; Selen, L P J; Halfwerk, K; Koppen, M; Corneil, B D; Medendorp, W P

    2016-09-01

    The natural world continuously presents us with many opportunities for action, and thus a process of target selection must precede action execution. While there has been considerable progress in understanding target selection in stationary environments, little is known about target selection when we are in motion. Here we investigated the effect of self-motion signals on saccadic target selection in a dynamic environment. Human subjects were sinusoidally translated (f = 0.6 Hz, 30-cm peak-to-peak displacement) along an interaural axis with a vestibular sled. During the motion two visual targets were presented asynchronously but equidistantly on either side of fixation. Subjects had to look at one of these targets as quickly as possible. With an adaptive approach, the time delay between these targets was adjusted until the subject selected both targets equally often. We determined this balanced time delay for different phases of the motion in order to distinguish the effects of body acceleration and velocity on saccadic target selection. Results show that acceleration (or position, as these are indistinguishable during sinusoidal motion), but not velocity, affects target selection for saccades. Subjects preferred to look at targets in the direction of the acceleration-the leftward target was preferred when the sled accelerated to the left, and vice versa. Saccadic reaction times mimicked this selection bias by being reliably shorter to targets in the direction of acceleration. Our results provide evidence that saccade target selection mechanisms are modulated by self-motion signals, which could be derived directly from the otolith system. PMID:27281751

  12. Estimation of muscle response using three-dimensional musculoskeletal models before impact situation: a simulation study.

    PubMed

    Bae, Tae Soo; Loan, Peter; Choi, Kuiwon; Hong, Daehie; Mun, Mu Seong

    2010-12-01

    When car crash experiments are performed using cadavers or dummies, the active muscles' reaction on crash situations cannot be observed. The aim of this study is to estimate muscles' response of the major muscle groups using three-dimensional musculoskeletal model by dynamic simulations of low-speed sled-impact. The three-dimensional musculoskeletal models of eight subjects were developed, including 241 degrees of freedom and 86 muscles. The muscle parameters considering limb lengths and the force-generating properties of the muscles were redefined by optimization to fit for each subject. Kinematic data and external forces measured by motion tracking system and dynamometer were then input as boundary conditions. Through a least-squares optimization algorithm, active muscles' responses were calculated during inverse dynamic analysis tracking the motion of each subject. Electromyography for major muscles at elbow, knee, and ankle joints was measured to validate each model. For low-speed sled-impact crash, experiment and simulation with optimized and unoptimized muscle parameters were performed at 9.4 m/h and 10 m/h and muscle activities were compared among them. The muscle activities with optimized parameters were closer to experimental measurements than the results without optimization. In addition, the extensor muscle activities at knee, ankle, and elbow joint were found considerably at impact time, unlike previous studies using cadaver or dummies. This study demonstrated the need to optimize the muscle parameters to predict impact situation correctly in computational studies using musculoskeletal models. And to improve accuracy of analysis for car crash injury using humanlike dummies, muscle reflex function, major extensor muscles' response at elbow, knee, and ankle joints, should be considered. PMID:21142325

  13. Self-tuning at large (distances): 4D description of runaway dilaton capture

    NASA Astrophysics Data System (ADS)

    Burgess, C. P.; Diener, Ross; Williams, M.

    2015-10-01

    We complete here a three-part study (see also arXiv:1506.08095 and arXiv:1508.00856) of how codimension-two objects back-react gravitationally with their environment, with particular interest in situations where the transverse `bulk' is stabilized by the interplay between gravity and flux-quantization in a dilaton-Maxwell-Einstein system such as commonly appears in higher-dimensional supergravity and is used in the Supersymmetric Large Extra Dimensions (SLED) program. Such systems enjoy a classical flat direction that can be lifted by interactions with the branes, giving a mass to the would-be modulus that is smaller than the KK scale. We construct the effective low-energy 4D description appropriate below the KK scale once the transverse extra dimensions are integrated out, and show that it reproduces the predictions of the full UV theory for how the vacuum energy and modulus mass depend on the properties of the branes and stabilizing fluxes. In particular we show how this 4D theory learns the news of flux quantization through the existence of a space-filling four-form potential that descends from the higher-dimensional Maxwell field. We find a scalar potential consistent with general constraints, like the runaway dictated by Weinberg's theorem. We show how scale-breaking brane interactions can give this potential minima for which the extra-dimensional size, ℓ, is exponentially large relative to underlying physics scales, r B , with ℓ 2 = r B 2 e - φ where - φ ≫ 1 can be arranged with a small hierarchy between fundamental parameters. We identify circumstances where the potential at the minimum can (but need not) be parametrically suppressed relative to the tensions of the branes, provide a preliminary discussion of the robustness of these results to quantum corrections, and discuss the relation between what we find and earlier papers in the SLED program.

  14. The effects of physical contact type on the internal and external demands during a rugby league match simulation protocol.

    PubMed

    Norris, Jonathan P; Highton, Jamie; Hughes, Stephen F; Twist, Craig

    2016-10-01

    The aim of this study was to investigate how the type of contact influences physiological, perceptual and locomotive load during a simulated rugby league match. Eleven male university rugby league players performed two trials of the rugby league movement simulation protocol for interchange forwards with a traditional soft tackle bag and a weighted tackle sled to replicate contact demands. The interchange forward-specific simulation was chosen given the contact frequency is higher for this group of players compared to whole match players. Locomotive rate, sprint speed, tackle intensity, heart rate (HR) and rating of perceived exertion were analysed during the first and second bouts that replicated two ~23 min on-field passages. Countermovement jump (CMJ) was measured before and immediately after each trial. More time was spent in heart rate zone between 91 and 100% HRpeak during the first (effect size ± 90% confidence interval: 0.44 ± 0.49) and second bouts (0.44 ± 0.43), and larger (0.6 ± 0.69) decrements in CMJ performance were observed during the sled trial (5.9, s = 4.9%) compared to the bag trial (2.6, s = 5.4%). Changing the type of contact during the match simulation subtly altered both the internal and external loads on participants. Using a standard tackle bag results in faster sprint speed to contact, but lower overall high-intensity running. Conversely, a heavier tackle object increases the internal load and results in greater lower limb neuromuscular fatigue as reflected by the decrease in CMJ performance. PMID:26860532

  15. CO SPECTRAL LINE ENERGY DISTRIBUTIONS OF INFRARED-LUMINOUS GALAXIES AND ACTIVE GALACTIC NUCLEI

    SciTech Connect

    Papadopoulos, Padeli P.; Van der Werf, Paul; Isaak, Kate; Xilouris, Emmanuel M. E-mail: pvdwerf@strw.leidenuniv.n E-mail: xilouris@astro.noa.g

    2010-06-01

    We report on new sensitive CO J = 6-5 line observations of several luminous infrared galaxies (LIRGs; L {sub IR}(8-1000 {mu}m) {approx}> 10{sup 11} L {sub sun}), 36% (8/22) of them ultraluminous infrared galaxies (ULIRGs) (L {sub IR}>10{sup 12} L {sub sun}), and two powerful local active galactic nuclei (AGNs)-the optically luminous QSO PG 1119+120 and the powerful radio galaxy 3C 293-using the James Clerk Maxwell Telescope on Mauna Kea in Hawaii. We combine these observations with existing low-J CO data and dust emission spectral energy distributions in the far-infrared-submillimeter from the literature to constrain the properties of the star-forming interstellar medium (ISM) in these systems. We then build the first local CO spectral line energy distributions (SLEDs) for the global molecular gas reservoirs that reach up to high J-levels. These CO SLEDs are neither biased by strong lensing (which affects many of those constructed for high-redshift galaxies), nor suffer from undersampling of CO-bright regions (as most current high-J CO observations of nearby extended systems do). We find: (1) a significant influence of dust optical depths on the high-J CO lines, suppressing the J = 6-5 line emission in some of the most IR-luminous LIRGs, (2) low global CO line excitation possible even in vigorously star-forming systems, (3) the first case of a shock-powered high-excitation CO SLED in the radio galaxy 3C 293 where a powerful jet-ISM interaction occurs, and (4) unusually highly excitated gas in the optically powerful QSO PG 1119+120. In Arp 220 and possibly other (U)LIRGs very faint CO J = 6-5 lines can be attributed to significant dust optical depths at short submillimeter wavelengths immersing those lines in a strong dust continuum, and also causing the C{sup +} line luminosity deficit often observed in such extreme starbursts. Re-analysis of the CO line ratios available for submillimeter galaxies suggests that similar dust opacities also may be present in these

  16. Observing Radiative Properties of a Thinner, Seasonal Arctic Ice Pack

    NASA Astrophysics Data System (ADS)

    Hudson, S. R.; Nicolaus, M.; Granskog, M.; Gerland, S.; Wang, C.

    2011-12-01

    variability. For this, we have developed a radiation sled for measuring the full radiation budget of sea ice at a grid of locations to observe the variability within an area similar to a satellite pixel or model grid cell. Based on a modified dog sled, it carries upward and downward looking longwave and shortwave broadband radiometers, a spectral radiometer (350 to 2500 nm) for measuring spectral albedo, cameras to record surface and ground conditions at each measurement site, a thermometer, hygrometer, and GPS. Small enough to be deployed from a ship at short ice stations, it can also be used at longer stations to observe the effect of the spatial variability on the temporal variability. When combined with measurements or estimates of the sensible and latent heat fluxes, a full picture of the large-scale energy budget and its small-scale variations is obtained, valuable insight for parameterization and remote sensing product development. Surface profiles with the sled can be complemented by under-ice profiles made with a spectral radiometer mounted on an ROV or carried by a diver, providing a measure of the spatial variability of the partitioning of the absorbed solar energy into the ice and water.

  17. Methods to mitigate injury to toddlers in near-side impact crashes.

    PubMed

    Kapoor, Tanya; Altenhof, William; Howard, Andrew; Rasico, Jim; Zhu, Fuchun

    2008-11-01

    This research focuses on the injury potential of children seated in forward-facing child safety seats during side impact crashes in a near-side seated position. Side impact dynamic sled tests were conducted by NHTSA at Transportation Research Center Inc. (TRC) using a Hybrid III 3-year-old child dummy seated in a convertible forward/rearward child safety seat. The seat was equipped with a LATCH and a top tether and the dummy was positioned in forward-facing/near-side configuration. The test was completed using an acceleration pulse with a closing speed of 24.1 km/h, in the presence of a rigid wall and absence of a vehicle body. A fully deformable finite element model of a child restraint seat, for side impact crash investigations, has been developed which has also been previously validated for frontal and far side impacts. A numerical model utilizing a Hybrid III 3-year-old dummy, employing a similar set-up as the experimental sled test was generated and simulated using LS DYNA. The numerical model was validated by comparing the head and the chest accelerations, resultant upper and lower neck forces and moments from the experimental and numerical tests. The simulation results were observed to be in good agreement to the experimental observations. A numerical model of the near-side laboratory tests, utilizing a Q3s child dummy, was also created for parametric studies regarding different ISOFIX configurations. Further, numerical simulations were completed for both the dummy models with rectangular and cross-shaped sections of rigid ISOFIX systems. In addition, studies were conducted to confine lateral movement of the dummy's head by adding energy absorbing foam on the side wings in the vicinity of the contact region of the CRS. It was observed that the use of rigid ISOFIX system reduced the lateral displacement of the CRS and different injury parameters. Addition of energy absorbing foam blocks was effective in further reducing the lateral displacement of the dummy

  18. WATER VAPOR IN NEARBY INFRARED GALAXIES AS PROBED BY HERSCHEL

    SciTech Connect

    Yang Chentao; Gao Yu; Liu Daizhong; Isaak, K. G.; Downes, D.; Van der Werf, P. P.; Lu Nanyao

    2013-07-10

    We report the first systematic study of the submillimeter water vapor rotational emission lines in infrared (IR) galaxies based on the Fourier Transform Spectrometer (FTS) data of Herschel SPIRE. Among the 176 galaxies with publicly available FTS data, 45 have at least one H{sub 2}O emission line detected. The H{sub 2}O line luminosities range from {approx}1 Multiplication-Sign 10{sup 5} L{sub Sun} to {approx}5 Multiplication-Sign 10{sup 7} L{sub Sun} while the total IR luminosities (L{sub IR}) have a similar spread ({approx}1-300 Multiplication-Sign 10{sup 10} L{sub Sun }). In addition, emission lines of H{sub 2}O{sup +} and H{sub 2}{sup 18}O are also detected. H{sub 2}O is found, for most galaxies, to be the strongest molecular emitter after CO in FTS spectra. The luminosity of the five most important H{sub 2}O lines is near-linearly correlated with L{sub IR}, regardless of whether or not strong active galactic nucleus signature is present. However, the luminosity of H{sub 2}O(2{sub 11}-2{sub 02}) and H{sub 2}O(2{sub 20}-2{sub 11}) appears to increase slightly faster than linear with L{sub IR}. Although the slope turns out to be slightly steeper when z {approx} 2-4 ULIRGs are included, the correlation is still closely linear. We find that L{sub H{sub 2O}}/L{sub IR} decreases with increasing f{sub 25}/f{sub 60}, but see no dependence on f{sub 60}/f{sub 100}, possibly indicating that very warm dust contributes little to the excitation of the submillimeter H{sub 2}O lines. The average spectral line energy distribution (SLED) of the entire sample is consistent with individual SLEDs and the IR pumping plus collisional excitation model, showing that the strongest lines are H{sub 2}O(2{sub 02}-1{sub 11}) and H{sub 2}O(3{sub 21}-3{sub 12}).

  19. Characterization of an erbium-doped fiber amplifier as a light source and development of a near-infrared spectrophotometer based on the EDFA and an acoustooptic tunable filter.

    PubMed

    Tran, C D; Gao, G H

    1996-07-01

    A novel light source for the near-infrared region which has the highest intensity and widest spectral bandwidth of all near-IR light sources has been developed. The system is based on a single-mode fiber (about 18 m long) doped with Er3+ ion. The doped ion produces amplified spontaneous emission (ASE) in the near-IR region (from 1500 to 1600 nm) when it is excited by a diode laser at 980 nm. Because the diode laser is fusion-spliced directly to the doped fiber, the system is compact, all-solid-state, reliable, and stable and requires little maintenance. Its ASE output intensity was found to be comparable with those of diode lasers currently available for this near-IR region and is much higher than those of conventional halogen-tungsten lamps and the so-called (high-intensity) superluminescent light emitting diodes (SLEDs). Its spectral bandwidth is, however, much wider than those of the diode lasers and the SLEDs. Even higher intensity can be obtained from the doped fiber when a low-intensity (1 mW) light from a 1550-nm laser diode is introduced into the doped fiber. The intensity is enhanced (up to 7 times compared to the ASE) because the input light is amplified by the doped fiber. Furthermore, the output intensity of this erbium-doped fiber amplifier (EDFA) can be appropriately adjusted to provide relatively higher output intensity at any range of wavelengths (within this 1500-1600-nm region) by simply changing the temperature and/or the driven current of the input diode laser. Subsequently, an acoustooptic tunable filter was used to provide a means to spectrally tune the EDFA rapidly and to develop an all-solid-state, compact near-IR spectrophotometer which not only is very sensitive, stable, and reliable but also has a very high throughput. This spectrophotometer can detect water in ethanol at a limit of detection of 10 ppm. More importantly, the high through-put makes it possible to use the instrument to measure spectra of highly absorbing samples (e

  20. Antenna Measurements: Test & Analysis of the Radiated Emissions/Immunity of the NASA/Orion Spacecraft Dart Parachute Simulator & Prototype Capsule - The Crew Exploration Vehicle

    NASA Technical Reports Server (NTRS)

    Norgard, John D.

    2012-01-01

    For future NASA Manned Space Exploration of the Moon and Mars, a blunt body capsule, called the Orion Crew Exploration Vehicle (CEV), composed of a Crew Module (CM) and a Service Module (SM), with a parachute decent assembly is planned for reentry back to Earth. A Capsule Parachute Assembly System (CPAS) is being developed for preliminary prototype parachute drop tests at the Yuma Proving Ground (YPG) to simulate high-speed reentry to Earth from beyond Low-Earth-Orbit (LEO) and to provide measurements of position, velocity, acceleration, attitude, temperature, pressure, humidity, and parachute loads. The primary and secondary (backup) avionics systems on CPAS also provide mission critical firing events to deploy, reef, and release the parachutes in three stages (extraction, drogues, mains) using mortars and pressure cartridge assemblies. In addition, a Mid-Air Delivery System (MDS) is used to separate the capsule from the sled that is used to eject the capsule from the back of the drop plane. Also, high-speed and high-definition cameras in a Video Camera System (VCS) are used to film the drop plane extraction and parachute landing events. Intentional and unintentional radiation emitted from and received by antennas and electronic devices on/in the CEV capsule, the MDS sled, and the VCS system are being tested for radiated emissions/immunity (susceptibility) (RE/RS). To verify Electromagnetic Compatibility (EMC) of the Orion capsule, Electromagnetic Interference (EMI) measurements are being made inside a semi-anechoic chamber at NASA/JSC on the components of the CPAS system. Measurements are made at 1m from the components-under-test (CUT). In addition, EMI measurements of the integrated CEV system are being made inside a hanger at YPG. These measurements are made in a complete circle, at 30? angles or less, around the Orion Capsule, the spacecraft system under-test (SUT). Near-field B-Dot probe measurements on the surface of the Orion capsule are being extrapolated

  1. Submillimeter H2O emission in infrared bright galaxies near and far

    NASA Astrophysics Data System (ADS)

    Yang, Chentao

    2015-08-01

    We conduct the first systematic study of the submillimeter H2O rotational emission lines in the infrared bright galaxies from local to high redshift universe observed by FTS/Herschel and PdBI. Among the 176 local galaxies, 45 have at least one H2O emission line detected. And H2O is found to be the strongest molecular emitter after CO in FTS spectra. For the five most detected H2O lines, the luminosity is near-linearly correlated with LIR no matter strong AGN signature is present or not. However, the luminosity of H2O (211-202) and H2O (220-211) appears to increase slightly faster than linear with LIR. Although the slope turns out to be slightly steeper when z˜2-4 ULIRGs (Ultra-Luminous InfraRed Galaxies) are included, the correlation is still not far from linear. We find that LH2O/LIR decreases with increasing infrared color f25/f60, but nearly no dependence on f60/f100, possibly indicating that very warm dust contributes little to the excitation of submillimeter H2O lines, and this is consistent with later modeling studies. The average spectral line energy distribution (SLED) of entire sample is consistent with individual SLEDs and the IR pumping plus collisional excitation model, showing that the strongest lines are H2O (202-111) and H2O (321-312). Moreover, we have detected J=2 and J=3 H2O lines in 17 high-z lensed ULIRGs that picked from H-ATLAS survey. Most of their line profiles are similar to those of the high-J CO lines, indicating the similar location. By comparing the map of H2O and dust continuum emission, the emission from H2O is more compact than dust. A slightly faster than linear correlation has been found in these high-z ULIRGs. However, high resolution study by the telescopes, e.g., NOEMA and ALMA, is still need for studying the spatial distribution of the water vapor.

  2. A method for quantitatively estimating diffuse and discrete hydrothermal discharge

    NASA Astrophysics Data System (ADS)

    Baker, Edward T.; Massoth, Gary J.; Walker, Sharon L.; Embley, Robert W.

    1993-07-01

    Submarine hydrothermal fluids discharge as undiluted, high-temperature jets and as diffuse, highly diluted, low-temperature percolation. Estimates of the relative contribution of each discharge type, which are important for the accurate determination of local and global hydrothermal budgets, are difficult to obtain directly. In this paper we describe a new method of using measurements of hydrothermal tracers such as Fe/Mn, Fe/heat, and Mn/heat in high-temperature fluids, low-temperature fluids, and the neutrally buoyant plume to deduce the relative contribution of each discharge type. We sampled vent fluids from the north Cleft vent field on the Juan de Fuca Ridge in 1988, 1989 and 1991, and plume samples every year from 1986 to 1991. The tracers were, on average, 3 to 90 times greater in high-temperature than in low-temperature fluids, with plume values intermediate. A mixing model calculates that high-temperature fluids contribute only ˜ 3% of the fluid mass flux but > 90% of the hydrothermal Fe and > 60% of the hydrothermal Mn to the overlying plume. Three years of extensive camera-CTD sled tows through the vent field show that diffuse venting is restricted to a narrow fissure zone extending for 18 km along the axial strike. Linear plume theory applied to the temperature plumes detected when the sled crossed this zone yields a maximum likelihood estimate for the diffuse heat flux of8.9 × 10 4 W/m, for a total flux of 534 MW, considering that diffuse venting is active along only one-third of the fissure system. For mean low- and high-temperature discharge of 25°C and 319°C, respectively, the discrete heat flux must be 266 MW to satisfy the mass flux partitioning. If the north Cleft vent field is globally representative, the assumption that high-temperature discharge dominates the mass flux in axial vent fields leads to an overestimation of the flux of many non-conservative hydrothermal species by about an order of magnitude.

  3. The ‘W’ Prawn-Trawl with Emphasised Drag-Force Transfer to Its Centre Line to Reduce Overall System Drag

    PubMed Central

    Balash, Cheslav; Sterling, David; Binns, Jonathan; Thomas, Giles; Bose, Neil

    2015-01-01

    For prawn trawling systems, drag reduction is a high priority as the trawling process is energy intensive. Large benefits have occurred through the use of multiple-net rigs and thin twine in the netting. An additional positive effect of these successful twine-area reduction strategies is the reduced amount of otter board area required to spread the trawl systems, which leads to further drag reduction. The present work investigated the potential of redirecting the drag-strain within a prawn trawl away from the wings and the otter boards to the centre line of the trawl, where top and bottom tongues have been installed, with an aim to minimise the loading/size of the otter boards required to spread the trawl. In the system containing the new ‘W’ trawl, the drag redirected to the centre-line tongues is transferred forward through a connected sled and towing wires to the trawler. To establish the extent of drag redirection to the centre-line tongues and the relative drag benefits of the new trawl system, conventional and ‘W’ trawls of 3.65 m headline length were tested firstly over a range of spread ratios in the flume tank, and subsequently at optimum spread ratio in the field. The developed ‘W’ trawl effectively directed 64% of netting-drag off the wings and onto the centre tongues, which resulted in drag savings in the field of ∼20% for the associated ‘W’ trawl/otter-board/sled system compared to the traditional trawl/otter-board arrangement in a single trawl or twin rig configuration. Furthermore, based on previously published data, the new trawl when used in a twin rig system is expected to provide approximately 12% drag reduction compared to quad rig. The twin ‘W’ trawl system also has benefits over quad rig in that a reduced number of cod-end/By-catch Reduction Device units need to be installed and attended each tow. PMID:25751251

  4. The Next Linear Collider Test Accelerator's RF Pulse Compression And Transmission

    SciTech Connect

    Tantawi, S.G.; Adelphson, C.; Holmes, S.; Lavine, Theodore L.; Loewen, R.J.; Nantista, C.; Pearson, C.; Pope, R.; Rifkin, J.; Ruth, R.D.; Vlieks, A.E.; /SLAC

    2011-09-14

    The overmoded rf transmission and pulsed power compression system for SLAC's Next Linear Collider (NLC) program requires a high degree of transmission efficiency and mode purity to be economically feasible. To this end, a number of new, high power components and systems have been developed at X-band, which transmit rf power in the low loss, circular TE01 mode with negligible mode conversion. In addition, a highly efficient SLED-II* pulse compressor has been developed and successfully tested at high power. The system produced a 200 MW, 250 ns wide pulse with a near-perfect flat-top. In this paper we describe the design and test results of the high power pulse compression system using SLED-II. The NLC rf systems use low loss highly over-moded circular waveguides operating in the TE01 mode. The efficiency of the systems is sensitive to the mode purity of the mode excited inside these guides. We used the so called flower petal mode transducer [2] to excite the TE01 mode. This type of mode transducer is efficient, compact and capable of handling high levels of power. To make more efficient systems, we modified this device by adding several mode selective chokes to act as mode purifiers. To manipulate the rf signals we used these modified mode converters to convert back and forth between over-moded circular waveguides and single-moded WR90 rectangular waveguides. Then, we used the relatively simple rectangular waveguide components to do the actual manipulation of rf signals. For example, two mode transducers and a mitered rectangular waveguide bend comprise a 90 degree bend. Also, a magic tee and four mode transducers would comprise a four-port-hybrid, etc. We will discuss the efficiency of an rf transport system based on the above methodology. We also used this methodology in building the SLEDII pulse compression system. At SLAC we built 4 of these pulse systems. In this paper we describe the SLEDII system and compare the performance of these 4 systems at SLAC. We

  5. Study of the suit inflation effect on crew safety during landing using a full-pressure IVA suit for new-generation reentry space vehicles

    NASA Astrophysics Data System (ADS)

    Wataru, Suzuki

    Recently, manned space capsules have been recognized as beneficial and reasonable human space vehicles again. The Dragon capsule already achieved several significant successes. The Orion capsule is going to be sent to a high-apogee orbit without crews for experimental purposes in September 2014. For such human-rated space capsules, the study of acceleration impacts against the human body during splashdown is essential to ensure the safety of crews. Moreover, it is also known that wearing a full pressure rescue suit significantly increases safety of a crew, compared to wearing a partial pressure suit. This is mainly because it enables the use of a personal life support system independently in addition to that which installed in the space vehicle. However, it is unclear how the inflation of the full pressure suit due to pressurization affects the crew safety during splashdown, especially in the case of the new generation manned space vehicles. Therefore, the purpose of this work is to investigate the effect of the suit inflation on crew safety against acceleration impact during splashdown. For this objective, the displacements of the safety harness in relation with the suit, a human surrogate, and the crew seats during pressurizing the suit in order to determine if the safety and survivability of a crew can be improved by wearing a full pressure suit. For these tests, the DL/H-1 full pressure IVA suit, developed by Pablo de Leon and Gary L. Harris, will be used. These tests use image analysis techniques to determine the displacements. It is expected, as a result of these tests, that wearing a full pressure suit will help to mitigate the impacts and will increase the safety and survivability of a crew during landing since it works as a buffer to mitigate impact forces during splashdown. This work also proposes a future plan for sled test experiments using a sled facility such as the one in use by the Civil Aerospace Medical Institute (CAMI) for experimental validation

  6. Broadband Lidar Technique for Precision CO2 Measurement

    NASA Technical Reports Server (NTRS)

    Heaps, William S.

    2008-01-01

    Presented are preliminary experimental results, sensitivity measurements and discuss our new CO2 lidar system under development. The system is employing an erbium-doped fiber amplifier (EDFA), superluminescent light emitting diode (SLED) as a source and our previously developed Fabry-Perot interferometer subsystem as a detector part. Global measurement of carbon dioxide column with the aim of discovering and quantifying unknown sources and sinks has been a high priority for the last decade. The goal of Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) mission is to significantly enhance the understanding of the role of CO2 in the global carbon cycle. The National Academy of Sciences recommended in its decadal survey that NASA put in orbit a CO2 lidar to satisfy this long standing need. Existing passive sensors suffer from two shortcomings. Their measurement precision can be compromised by the path length uncertainties arising from scattering within the atmosphere. Also passive sensors using sunlight cannot observe the column at night. Both of these difficulties can be ameliorated by lidar techniques. Lidar systems present their own set of problems however. Temperature changes in the atmosphere alter the cross section for individual CO2 absorption features while the different atmospheric pressures encountered passing through the atmosphere broaden the absorption lines. Currently proposed lidars require multiple lasers operating at multiple wavelengths simultaneously in order to untangle these effects. The current goal is to develop an ultra precise, inexpensive new lidar system for precise column measurements of CO2 changes in the lower atmosphere that uses a Fabry-Perot interferometer based system as the detector portion of the instrument and replaces the narrow band laser commonly used in lidars with the newly available high power SLED as the source. This approach reduces the number of individual lasers used in the system from three or more

  7. Energy absorption capability of foam-based composite materials and their applications as seat cushions in aircraft crashworthiness

    NASA Astrophysics Data System (ADS)

    Kh. Beheshti, Hamid

    This study is focusing on the application of foam materials in aviation. These materials are being used for acoustic purposes, as padding in the finished interior panels of the aircraft, and as seat cushions. Foams are mostly used in seating applications. Since seat cushion is directly interacting with the body of occupant, it has to be ergonomically comfortable beside of absorbing the energy during the impact. All the seats and seat cushions have to pass regulations defined by Federal Aviation Administration (FAA). In fact, all airplane companies are required to certify the subcomponents of aircrafts before installing them on the main structure, fuselage. Current Federal Aviation Administration Regulations require a dynamic sled test of the entire seat system for certifying the seat cushions. This dynamic testing is required also for replacing the deteriorated cushions with new cushions. This involves a costly and time-consuming certification process. AGATE group has suggested a procedure based on quasi-static testing in order to certify new seat cushions without conducting full-scale dynamic sled testing. AGATE subcomponent methodology involves static tests of the energy-absorbing foam cushions and design validation by conducting a full-scale dynamic seat test. Microscopic and macroscopic studies are necessary to provide a complete understanding about performance of foams during the crash. Much investigation has been done by different sources to obtain the reliable modeling in terms of demonstration of mechanical behavior of foams. However, rate sensitivity of foams needs more attention. A mathematical hybrid dynamic model for the cushion underneath of the human body will be taken into consideration in this research. Analytical and finite element codes such as MADYMO and LS-DYNA codes have the potential to greatly speed up the crashworthy design process, to help certify seats and aircraft to dynamic crash loads, to predict seat and occupant response to impact

  8. Evaluation of Human and Anthropomorphic Test Device Finite Element Models under Spaceflight Loading Conditions

    NASA Technical Reports Server (NTRS)

    Putnam, Jacob P.; Untaroiu, Costin; Somers. Jeffrey

    2014-01-01

    In an effort to develop occupant protection standards for future multipurpose crew vehicles, the National Aeronautics and Space Administration (NASA) has looked to evaluate the test device for human occupant restraint with the modification kit (THOR-K) anthropomorphic test device (ATD) in relevant impact test scenarios. With the allowance and support of the National Highway Traffic Safety Administration, NASA has performed a series of sled impact tests on the latest developed THOR-K ATD. These tests were performed to match test conditions from human volunteer data previously collected by the U.S. Air Force. The objective of this study was to evaluate the THOR-K finite element (FE) model and the Total HUman Model for Safety (THUMS) FE model with respect to the tests performed. These models were evaluated in spinal and frontal impacts against kinematic and kinetic data recorded in ATD and human testing. Methods: The FE simulations were developed based on recorded pretest ATD/human position and sled acceleration pulses measured during testing. Predicted responses by both human and ATD models were compared to test data recorded under the same impact conditions. The kinematic responses of the models were quantitatively evaluated using the ISO-metric curve rating system. In addition, ATD injury criteria and human stress/strain data were calculated to evaluate the risk of injury predicted by the ATD and human model, respectively. Results: Preliminary results show well-correlated response between both FE models and their physical counterparts. In addition, predicted ATD injury criteria and human model stress/strain values are shown to positively relate. Kinematic comparison between human and ATD models indicates promising biofidelic response, although a slightly stiffer response is observed within the ATD. Conclusion: As a compliment to ATD testing, numerical simulation provides efficient means to assess vehicle safety throughout the design process and further improve the

  9. Cystic echinococcosis in the Arctic and Sub-Arctic.

    PubMed

    Rausch, R L

    2003-01-01

    The northern biotype of Echinococcus granulosus occurs throughout the holarctic zones of tundra and taiga, from eastern Fennoscandia to the Bering Strait in Eurasia and in North America from arctic Alaska approximately to the northern border of the United States. The cycle of the cestode is complex in taiga at lower latitudes, because of the greater diversity of potential hosts. In the Arctic and Subarctic, however, four patterns of predator/prey relationships may be discerned. Two natural cycles involve the wolf and wild reindeer and the wolf and elk (moose), respectively. Where deer of the two species coexist, both are prey of the wolf; the interactions of the wolf and elk are here described on the basis of long-term observations made on Isle Royale (in Lake Superior near the southern limit of taiga), where only the wolf and elk serve as hosts for E. granulosus. A synanthropic cycle involving herding-dogs and domesticated reindeer caused hyperendemicity of cystic echinococcosis in arctic Eurasia, mainly in northeastern Siberia. The 4th pattern, a semi-synanthropic cycle, formerly existed in Alaska, wherein sled-dogs of the indigenous hunters became infected by consuming the lungs of wild reindeer. The sequence of changes in life-style inherent in the process of acculturation affected the occurrence of cystic echinococcosis among nomadic Iñupiat in arctic Alaska. When those people became sedentary, the environs of their early villages soon became severely contaminated by faeces of dogs, and cases of cystic echinococcosis occurred. Compared to cystic echinococcosis caused by E. granulosus adapted to synanthropic hosts (dog and domestic ungulates), the infection produced by the northern biotype is relatively benign. Nearly all diagnosed cases of cystic echinococcosis (> 300) in Alaska have occurred in indigenous people; only one fatality has been recorded (in a non-indigenous person). After sled-dogs were replaced by machines, cases have become rare in Alaska. A

  10. High-Power Multimode X-Band RF Pulse Compression System for Future Linear Colliders

    SciTech Connect

    Tantawi, S.G.; Nantista, C.D.; Dolgashev, V.A.; Pearson, C.; Nelson, J.; Jobe, K.; Chan, J.; Fant, K.; Frisch, J.; Atkinson, D.; /LLNL, Livermore

    2005-08-10

    We present a multimode X-band rf pulse compression system suitable for a TeV-scale electron-positron linear collider such as the Next Linear Collider (NLC). The NLC main linac operating frequency is 11.424 GHz. A single NLC rf unit is required to produce 400 ns pulses with 475 MW of peak power. Each rf unit should power approximately 5 m of accelerator structures. The rf unit design consists of two 75 MW klystrons and a dual-moded resonant-delay-line pulse compression system that produces a flat output pulse. The pulse compression system components are all overmoded, and most components are designed to operate with two modes. This approach allows high-power-handling capability while maintaining a compact, inexpensive system. We detail the design of this system and present experimental cold test results. We describe the design and performance of various components. The high-power testing of the system is verified using four 50 MW solenoid-focused klystrons run off a common 400 kV solid-state modulator. The system has produced 400 ns rf pulses of greater than 500 MW. We present the layout of our system, which includes a dual-moded transmission waveguide system and a dual-moded resonant line (SLED-II) pulse compression system. We also present data on the processing and operation of this system, which has set high-power records in coherent and phase controlled pulsed rf.

  11. Windfield and trajectory models for tornado-propelled objects. Final report

    SciTech Connect

    Redmann, G.H.; Radbill, J.R.; Marte, J.E.; Dergarabedian, P.; Fendell, F.E.

    1983-03-01

    This is the final report of a three-phased research project to develop a six-degree-of-freedom mathematical model to predict the trajectories of tornado-propelled objects. The model is based on the meteorological, aerodynamic, and dynamic processes that govern the trajectories of missiles in a tornadic windfield. The aerodynamic coefficients for the postulated missiles were obtained from full-scale wind tunnel tests on a 12-inch pipe and car and from drop tests. Rocket sled tests were run whereby the 12-inch pipe and car were injected into a worst-case tornado windfield in order to verify the trajectory model. To simplify and facilitate the use of the trajectory model for design applications without having to run the computer program, this report gives the trajectory data for NRC-postulated missiles in tables based on given variables of initial conditions of injection and tornado windfield. Complete descriptions of the tornado windfield and trajectory models are presented. The trajectory model computer program is also included for those desiring to perform trajectory or sensitivity analyses beyond those included in the report or for those wishing to examine other missiles and use other variables.

  12. Joint helmet-mounted cueing system (JHMCS) helmet qualification testing requirements

    NASA Astrophysics Data System (ADS)

    Orf, Garry W.

    1998-08-01

    The Joint Helmet-Mounted Cueing System (JHMCS) program will provide capability to cue high off-boresight (HOBS) weapons to the operator's line of sight and to confirm weapon sensor LOS for the US Air Force and US Navy (USN) aircrew. This capability will ensure the USAF and USN pilots a first shot opportunity. The JHMCS incorporates an ejection-compatible helmet-mounted display system that will be installed on F- 15, F-16, F/A-18, and F-22 aircraft. The JHMCS includes a flight helmet with display optics, miniature cathode ray tube, magnetic receiver unit, miniature camera, automatic brightness control sensor, and microcontroller. The flight helmet for JHMCS is based on the new lightweight HGU-55A/P. This paper describes the requirements for the helmet qualification tests including: windblast, ejection tower, hanging harness, centrifuge, mass properties, energy attenuation and penetration resistance, noise attenuation, visor characteristics, compatibility demonstration, sled/in- flight ejection, water survival, standard conditions and environment. The test objective, success criteria, equipment configuration, and data collection requirements for each test is discussed.

  13. Polymer infiltration studies

    NASA Technical Reports Server (NTRS)

    Marchello, Joseph M.

    1993-01-01

    During the past three months, significant progress has been made on the preparation of carbon fiber composites using advanced polymer resins. The results are set forth in recent reports and publications, and will be presented at forthcoming national and international meetings. Current and ongoing research activities reported herein include: textile composites from powder-coated towpreg; role of surface coating in braiding; prepregger hot sled operation; ribbonizing powder-impregenated towpreg; textile composites from powder-coated towpreg; role of bulk factor powder curtain prepreg process advanced tow placement (ATP) open-section part warpage control. During the coming months research will be directed toward further development of the new powder curtain prepregging method and on ways to customize dry powder towpreg for textile and robotic applications in aircraft part fabrication. Studies of multi-tow powder prepregging and ribbon preparation will be conducted in conjunction with continued development of prepregging technology and the various aspects of composite part fabrication using customized towpreg. Also, during the period ahead work will continue on the analysis of the performance of the new solution prepregger.

  14. Magnetic levitation systems for future aeronautics and space research and missions

    NASA Technical Reports Server (NTRS)

    Blankson, Isaiah M.; Mankins, John C.

    1996-01-01

    The objectives, advantages, and research needs for several applications of superconducting magnetic levitation to aerodynamics research, testing, and space-launch are discussed. Applications include very large-scale magnetic balance and suspension systems for high alpha testing, support interference-free testing of slender hypersonic propulsion/airframe integrated vehicles, and hypersonic maglev. Current practice and concepts are outlined as part of a unified effort in high magnetic fields R&D within NASA. Recent advances in the design and construction of the proposed ground-based Holloman test track (rocket sled) that uses magnetic levitation are presented. It is protected that ground speeds of up to Mach 8 to 11 at sea-level are possible with such a system. This capability may enable supersonic combustor tests as well as ramjet-to-scramjet transition simulation to be performed in clean air. Finally a novel space launch concept (Maglifter) which uses magnetic levitation and propulsion for a re-usable 'first stage' and rocket or air-breathing combined-cycle propulsion for its second stage is discussed in detail. Performance of this concept is compared with conventional advanced launch systems and a preliminary concept for a subscale system demonstration is presented.

  15. Dramatic decline of unionid bivalves in offshore waters of western Lake Erie after infestation by the zebra mussel, Dreissena polymorpha

    USGS Publications Warehouse

    Schloesser, Don W.; Nalepa, Thomas F.

    1994-01-01

    Unionid bivalves and attached epizoic zebra mussels (Dreissena polymorpha) were collected at one index station in 1989, 1990, and 1991 and at 17 stations in 1991 in offshore waters of western Lake Erie of the Laurentian Great Lakes. Sampling at the index station revealed that the proportion of live unionids declined from 53% in September 1989 to 17% in May–June 1990 and to 0% in September 1990: this 100% mortality coincided with heavy infestation by zebra mussels. Quantitative sampling with a Ponar grab at the 17 stations in 1991 revealed a widespread and dramatic reduction in unionid populations. In 1982, five unionid species occurred at 35% of the stations at a density of 4/m2, whereas in 1991, no live unionid species were found. Qualitative sampling with an epibenthic sled at the 17 stations in 1991 yielded only 4 live specimens of 2 species (Amblema plicata plicata and Fusconaia flava) and 187 dead specimens of 10 species. These and other results indicate that unionid populations are being negatively affected by zebra mussels in the Great Lakes. Similar impacts on unionids are expected to occur where zebra mussels become abundant throughout North America.

  16. The effects of temperature dependent recombination rates on performance of InGaN/GaN blue superluminescent light emitting diodes

    NASA Astrophysics Data System (ADS)

    Moslehi Milani, N.; Mohadesi, V.; Asgari, A.

    2015-07-01

    The effects of temperature dependent radiative and nonradiative recombination (Shockley-Read-Hall, spontaneous radiative, and Auger coefficients) on the spectral and power characteristics of a blue multiple quantum well (MQW) superluminescent light emitting diode (SLD or SLED) have been studied. The study is based on the rate equations model, where three rate equations corresponding to MQW active region, separate confinement heterostructure (SCH) layer, and spectral density of optical power are solved self-consistently with no k-selection energy dependent gain and quasi-Fermi level functions at steady state. We have taken into account the temperature effects on Shockley-Read-Hall (SRH), spontaneous radiative, and Auger recombination in the rate equations and have investigated the effects of temperature rising from 300 K to 375 K at a fixed current density. We examine this procedure for a moderate current density and interpret the spectral radiation power and light output power diagrams. The investigation reveals that the main loss due to temperature is related to Auger coefficient.

  17. Dynamic sagittal flexibility coefficients of the human cervical spine.

    PubMed

    Ivancic, Paul C; Ito, Shigeki; Panjabi, Manohar M

    2007-07-01

    The goal of the present study was to determine the dynamic sagittal flexibility coefficients, including coupling coefficients, throughout the human cervical spine using rear impacts. A biofidelic whole cervical spine model (n=6) with muscle force replication and surrogate head was rear impacted at 5 g peak horizontal accelerations of the T1 vertebra within a bench-top mini-sled. The dynamic main and coupling sagittal flexibility coefficients were calculated at each spinal level, head/C1 to C7/T1. The average flexibility coefficients were statistically compared (p<0.05) throughout the cervical spine. To validate the coefficients, the average computed displacement peaks, obtained using the average flexibility matrices and the measured load vectors, were statistically compared to the measured displacement peaks. The computed and measured displacement peaks showed good overall agreement, thus validating the computed flexibility coefficients. These peaks could not be statistically differentiated, with the exception of extension rotation at head/C1 and posterior shear translation at C7/T1. Head/C1 was significantly more flexible than all other spinal levels. The cervical spine was generally more flexible in posterior shear, as compared to axial compression. The coupling coefficients indicated that extension moment caused coupled posterior shear translation while posterior shear force caused coupled extension rotation. The present results may be used towards the designs of anthropometric test dummies and mathematical models that better simulate the cervical spine response during dynamic loading. PMID:17140545

  18. Variations in brightness temperature over cold first-year sea ice near Tuktoyaktuk, Northwest Territories

    NASA Technical Reports Server (NTRS)

    Lohanick, A. W.; Grenfell, T. C.

    1986-01-01

    Microwave radiometric temperature T(B) profiles of first-year sea ice were obtained along 70- to 100-m traverses, with sled-mounted radiometers at 10, 18.7, 33.6, and 37 GHz and an effective spot size of 30 cm. Measurements of T(B) as a function of nadir angle were obtained at selected sites along the traverses. Snow and ice properties were recorded and correlated with the T(B) measurements to infer the effect of snow cover and ice conditions on the radiometric temperature. T(B) correlated positively with the brine volume profile in the ice at several sites, suggesting that brine volume has a strong effect on T(B) under these conditions. An overall statistical comparison of snow thickness with T(B), when compared with previously published models, suggests that the effect of snow cover on the microwave transmission coefficient of the snow/ice interface may be an important contribution to the radiometric temperature at these frequencies. A model is proposed to explain the data.

  19. An integrated helmet and neck support (iHANS) for racing car drivers: a biomechanical feasibility study.

    PubMed

    Newman, James A; Withnall, Christopher; Wonnacott, Michael

    2012-10-01

    A new form of head and neck protection for racing car drivers is examined. The concept is one whereby the helmet portion of the system is attached, by way of a quick release clamp, to a collar-like platform which is supported on the driver's shoulders. The collar, which encircles the back and sides of the driver's neck, is held in place by way of the on-board restraint belts. The interior of the helmet portion of the assembly is large enough to provide adequate volitional head motion. The overall objective of the design is to remove the helmet from the wearer's head and thereby to mitigate the deleterious features of helmet wearing such as neck fatigue, poor ventilation and aerodynamic buffeting. Just as importantly, by transferring the weight of the helmet and all attendant reaction forces associated with inertial and impact loads to the shoulder complex (instead of to the neck), reduced head and neck injury probability should be achievable. This paper describes the concept development and the evolution of various prototype designs. Prototypes have been evaluated on track and sled tested in accordance with contemporary head neck restraint systems practice. Also discussed is a series of direct impact tests. In addition, low mass high velocity ballistic tests have been conducted and are reviewed herein. It is concluded that this new concept indeed does address most of the drawbacks of the customary helmet and that it generally can reduce the probability of head and neck injury. PMID:23625570

  20. Kinematics of the unrestrained vehicle occupants in side-impact crashes.

    PubMed

    Riley, P O; Arregui-Dalmases, C; Purtserov, S; Parent, D; Lessley, D J; Shaw, G; Crandall, J; Takayama, Shinichi; Ono, Koshiro; Kamiji, Koichi; Yasuki, Tsuyoshi

    2012-01-01

    A test series involving direct right-side impact of a moving wall on unsupported, unrestrained cadavers with no arms was undertaken to better understand human kinematics and injury mechanisms during side impact at realistic speeds. The tests conducted provided a unique opportunity for a detailed analysis of the kinematics resulting from side impact. Specifically, this study evaluated the 3-dimensional (3D) kinematics of 3 unrestrained male cadavers subjected to lateral impact by a multi-element load wall carried by a pneumatically propelled rail-mounted sled reproducing a conceptual side crash impact. Three translations and 3 rotations characterize the movement of a solid body in the space, the 6 degrees of freedom (6DoF) kinematics of 15 bone segments were obtained from the 3D marker motions and computed tomography (CT)-defined relationships between the maker array mounts and the bones. The moving wall initially made contact with the lateral aspect of the pelvis, which initiated lateral motion of the spinal segments beginning with the pelvis and moving sequentially up through the lumbar spine to the thorax. Analyzing the 6DoF motions kinematics of the ribs and sternum followed right shoulder contact with the wall. Overall thoracic motion was assessed by combining the thoracic bone segments as a single rigid body. The kinematic data presented in this research provides quantified subject responses and boundary condition interactions that are currently unavailable for lateral impact. PMID:22458795

  1. A new NASA LaRC Multi-Purpose Prepregging Unit

    NASA Technical Reports Server (NTRS)

    Wilkinson, S. P.; Marchello, J. M.; Dixon, D.; Johnston, N. J.

    1993-01-01

    A multi-purpose prepregging machine has been designed and built for NASA Langley Research Center. The machine has numerous advantages over existing units due to its various modular components. Each of these can be used individually or simultaneously depending on the required prepregging method. A reverse roll coater provides the ability to prepare thin films from typical hot-melt thermoset formulations. Also, if necessary, the design allows direct fiber impregnation within the reverse roll coater gap. Included in the impregnation module is a solution dip tank allowing the fabrication of thermoplastic prepregs from solution. The proceeding modules within the unit consist of four nip stations, two hot-plates, a hot-sled option and a high temperature oven. This paper describes the advantages of such a modular construction and discusses the various processing combinations available to the prepregger. A variety of high performance prepreg material systems were produced on IM7 (Hercules) carbon fiber. These included LaRC RP46, a PMR-type resin processed from methanol and two polyamide acids, LaRC IA and LaRC ITPI, prpregged from N-methyl pyrrolidinone (NMP). Parameters involved in the production of these prepreg materials are presented as are the mechanical properties of the resulting good quality laminates. A brief introduction into the existing prepregging science is presented. Topics relating to solution prepregging are identified with a focus on the current research effort and its future development.

  2. Development and validation of a modified Hybrid-III six-year-old dummy model for simulating submarining in motor-vehicle crashes.

    PubMed

    Hu, Jingwen; Klinich, Kathleen D; Reed, Matthew P; Kokkolaras, Michael; Rupp, Jonathan D

    2012-06-01

    In motor-vehicle crashes, young school-aged children restrained by vehicle seat belt systems often suffer from abdominal injuries due to submarining. However, the current anthropomorphic test device, so-called "crash dummy", is not adequate for proper simulation of submarining. In this study, a modified Hybrid-III six-year-old dummy model capable of simulating and predicting submarining was developed using MADYMO (TNO Automotive Safety Solutions). The model incorporated improved pelvis and abdomen geometry and properties previously tested in a modified physical dummy. The model was calibrated and validated against four sled tests under two test conditions with and without submarining using a multi-objective optimization method. A sensitivity analysis using this validated child dummy model showed that dummy knee excursion, torso rotation angle, and the difference between head and knee excursions were good predictors for submarining status. It was also shown that restraint system design variables, such as lap belt angle, D-ring height, and seat coefficient of friction (COF), may have opposite effects on head and abdomen injury risks; therefore child dummies and dummy models capable of simulating submarining are crucial for future restraint system design optimization for young school-aged children. PMID:21925918

  3. Advanced RF power sources for linacs

    SciTech Connect

    Wilson, P.B.

    1996-10-01

    In order to maintain a reasonable over-all length at high center-of-mass energy, the main linac of an electron-positron linear collider must operate at a high accelerating gradient. For copper (non-superconducting) accelerator structures, this implies a high peak power per unit length and a high peak power per RF source, assuming a limited number of discrete sources are used. To provide this power, a number of devices are currently under active development or conceptual consideration: conventional klystrons with multi-cavity output structures, gyroklystrons, magnicons, sheet-beam klystrons, multiple-beam klystrons and amplifiers based on the FEL principle. To enhance the peak power produced by an rf source, the SLED rf pulse compression scheme is currently in use on existing linacs, and new compression methods that produce a flatter output pulse are being considered for future linear colliders. This paper covers the present status and future outlook for the more important rf power sources and pulse compression systems. It should be noted that high gradient electron linacs have applications in addition to high-energy linear colliders; they can, for example, serve as compact injectors for FEL`s and storage rings.

  4. Cinephotogrammetric Evaluation Of Thoracic Deformation Due To Safety Belt Action During A Crash Test

    NASA Astrophysics Data System (ADS)

    Verriest, J. P.

    1983-07-01

    In order to estimate the thoracic injury tolerance of a belted automobile occupant and to get a better knowledge about the mechanical behaviour of the belt/torso system, the dynamic deformation of the thorax is evaluated under the action of a safety belt load. Therefore, during the whole duration of a crash test (about 120 ms) the relative displacement of a set of points drawn on the thorax surface is measured by cinephotogrammetry. Five 16 mm cine-photo cameras (3 fix around the impact area and 2 on board the sled) filming at 500 frames per second permit to cover the whole trunk surface. Synchronization of film data is done by interpolating on a common time base. The three-dimensional coordinates of the measurement points enable the reconstruction of the thorax surface as a set of contiguous triangular plane facets which can be projected on various reference planes for display purposes. For clarity of drawings, an algorithm determines hidden lines not to be plotted. Cuts parallel to the projection plane are performed. By changing the orientation of this plane and the number and the pace of the cuts, either contour maps or transversal cuts are obtained providing a visualization of deformation which can then be related to compressive forces and resulting injuries.

  5. Microgravity acceleration modeling for orbital systems

    NASA Technical Reports Server (NTRS)

    Knabe, Walter; Baugher, Charles R. (Editor)

    1990-01-01

    In view of the decisive importance of a disturbance-free environment on the Space Station, and on other orbital systems, for materials processing experiments, a theoretical and semi-experimental analysis of the acceleration environment to be expected on large orbiting spacecraft was undertaken. A unified model of such spacecraft cannot be established; therefore, a number of sub-models representing major components of typical large spacecraft must be investigated. In order to obtain experimental data of forces, a typical spacecraft - an engineering model of the Spacelab - was suspended on long ropes in a high-bay hangar, and equipped with a number of accelerometers. Active components on the Spacelab (fans, pumps, air conditioners, valves, levers) were operated, and astronautics moved boxes, drawers, sleds, and their own bodies. Generally speaking, the response of the Spacelab structure was very similar to the environment measured on Spacelabs SL-1, SL-2, and D-1. At frequencies in the broad range between 1 and about 100 Hz, acceleration peaks reached values of 10(exp -3) and 10(exp -2) g sub o, and even higher.

  6. Dynamics of the human linear vestibulo-ocular reflex at medium frequency and modification by short-term training

    NASA Technical Reports Server (NTRS)

    Shelhamer, M.; Roberts, D. C.; Zee, D. S.

    2000-01-01

    We study here the effect of a short-term training paradigm on the gain and phase of the human translational VOR (the linear VOR: LVOR). Subjects were exposed to lateral sinusoidal translations on a sled, at 0.5 Hz, 0.3 g peak acceleration. With subjects tracking a remembered target at 1.2 m, the LVOR (slow-phase) under these conditions typically has a phase lead or lag, and a gain that falls short of compensatory. To induce short-term adaptation (training), we presented an earth-fixed visual scene at 1.2 m during sinusoidal translation (x 1 viewing) for 20 minutes, so as to drive the LVOR toward compensatory phase and gain. We examined both the slow-phase and the saccadic responses to these stimuli. Testing after training showed changes in slow-component gain and phase which were mostly but not always in the compensatory direction. These changes were more consistent in naive subjects than in subjects who had previous LVOR experience. Changes in gain were seen with step as well as sinusoidal test stimuli; gain changes were not correlated with vergence changes. There was a strong correlation between gain changes and phase changes across subjects. Fast phases (catch-up saccades) formed a large component of the LVOR under our testing conditions (approximately 30% of the changes in gain but not in phase due to training.

  7. The design research of a spinel dome

    NASA Astrophysics Data System (ADS)

    Zhao, Hongwei; Hou, Tianjin; Zhu, Bin; Huang, Qiu; Gao, Zhifeng

    2011-08-01

    Based on the aerodynamic heating simulated results of a spinel middle-infrared (Mid IR) image guide missile dome flying at supersonic speed, a series of experiments are made and some methods of eliminating aero-heating effect are carried out successfully. First, a simulation experiment on the ground discarding an outside protective shell of a spinel dome is accomplished in order to inspect the withstanding impact ability of the dome. Second, an arc wind tunnel experiment is fulfilled to obtain thermal mechanics characteristic of the spinel dome, and a method to buildup obviously mechanics intensity is approved which is coating diamond protective layer on the external wall of the spinel dome. Third, two heated dome imaging experiments on the ground are made to study the aero-optical phenomenon. Finally, a rocket sled experiment of a guide missile head is made successfully. Experimental results show that when the guide missile head flies in a supersonic, by adjusting the frame integration time of detector etc. the aero-optic effect would decrease greatly.

  8. Oblique Loading in Post Mortem Human Surrogates from Vehicle Lateral Impact Tests using Chestbands.

    PubMed

    Yoganandan, Narayan; Humm, John R; Pintar, Frank A; Arun, Mike W J; Rhule, Heather; Rudd, Rodney; Craig, Matthew

    2015-11-01

    While numerous studies have been conducted to determine side impact responses of Post Mortem Human Surrogates (PMHS) using sled and other equipment, experiments using the biological surrogate in modern full-scale vehicles are not available. The present study investigated the presence of oblique loading in moving deformable barrier and pole tests. Threepoint belt restrained PMHS were positioned in the left front and left rear seats in the former and left front seat in the latter condition and tested according to consumer testing protocols. Three chestbands were used in each specimen (upper, middle and lower thorax). Accelerometers were secured to the skull, shoulder, upper, middle and lower thoracic vertebrae, sternum, and sacrum. Chestband signals were processed to determine magnitudes and angulations of peak deflections. The magnitude and timing of various signal peaks are given. Vehicle accelerations, door velocities, and seat belt loads are also given. Analysis of deformation contours, peak deflections, and angulations indicated that the left rear seated specimen were exposed to anterior oblique loading while left front specimens in both tests sustained essentially pure lateral loading to the torso. These data can be used to validate human body computational models. The occurrence of oblique loading in full-scale testing, hitherto unrecognized, may serve to stimulate the exploration of its role in injuries to the thorax and lower extremities in modern vehicles. It may be important to continue research in this area because injury metrics have a lower threshold for angled loading. PMID:26660738

  9. A turbojet-boosted two-stage-to-orbit space transportation system design study

    NASA Technical Reports Server (NTRS)

    Hepler, A. K.; Zeck, H.; Walker, W.; Scharf, W.

    1979-01-01

    The concept to use twin turbo-powered boosters for acceleration to supersonic staging speed followed by an all rocket powered orbiter stage was proposed. A follow-on design study was then made of the concept with the performance objective of placing a 29,483 Kg payload into a .2.6 X 195.3 km orbit. The study was performed in terms of analysis and trade studies, conceptual design, utility and economic analysis, and technology assessment. Design features of the final configuration included: strakes and area rule for improved take off and low transonic drag, variable area inlets, exits and turbine, and low profile fixed landing gear for turbojet booster stage. The payload required an estimated GLOW of 1,270,000 kg for injection in orbit. Each twin booster required afterburning turbojet engines each with a static sea level thrust rating of 444,800 N. Life cycle costs for this concept were comparable to a SSTO/SLED concept except for increased development cost due to the turbojet engine propulsion system.

  10. The Sanger-concept - A fully reusable winged launch vehicle

    NASA Astrophysics Data System (ADS)

    Lo, R. E.; Wolf, D. M.

    The present study compares winged space transportation systems with horizontal take-off (HTO) and vertical take-off (VTO), respectively. HTO vehicles were investigated at various take-off speeds and with various types of gear. While the type of acceleration till lift-off is a dominant factor for single-stage-to-orbit (SSTO) vehicles, its influence on two-stage-to-orbit (TSTO) vehicles is of lesser importance. This finding holds for lift-off velocity as well as for the type of gear. Among SSTO vehicles, a comparison of payload capability with HTO and VTO proves to be in favor of VTO in nearly all ranges. The only exceptions are at lift-off velocity Mach 0.6 in the range of lower GLOW and in a certain range for the sled-propelled vehicles. Concerning TSTO vehicles no essential differences between VTO and HTO can be discerned. Finally, different launch vehicles (SSTO and SANGER) with 20 Mg payload were compared, resulting in a definite advantage of the TSTO-SANGER solution in terms of performance and lower developmental risks.

  11. Design and testing of an energy-absorbing crewseat for the F/FB-111 aircraft. Volume 2: Data from seat testing

    NASA Technical Reports Server (NTRS)

    Shane, S. J.

    1985-01-01

    The unacceptably high injury rate during the escape sequence (including the ejection and ground impact) of the crew module for F/FB-111 aircraft is reviewed. A program to determine if the injury potential could be reduced by replacing the existing crewseats with energy absorbing crewseats is presented. An energy absorbing test seat is designed using much of the existing seat hardware. An extensive dynamic seat test series, designed to duplicate various crew module ground impact conditions is conducted at a sled test facility. Comparative tests with operational F-111 crewseats are also conducted. After successful dynamic testing of the seat, more testing is conducted with the seats mounted in an F-111 crew module. Both swing tests and vertical drop tests are conducted. The vertical drop tests are used to obtain comparative data between the energy absorbing and operational seats. Volume 1 describes the energy absorbing test seat and testing conducted, and evaluates the data from both test series. Volume 2 presents the data obtained during the seat test series, while Volume 3 presents the data from the crew module test series.

  12. Spatially resolved physical conditions of molecular gas: a zoom-in from circumnuclear region of M83 to Carina nebula.

    NASA Astrophysics Data System (ADS)

    Wu, Ronin; Madden, Suzanne; Galliano, Frédéric; Wilson, Christine; Onaka, Takashi; Nakamura, Tomohiko

    2015-08-01

    Since the launch of the Herschel Space Observatory, our understanding about the photo-dissociation regions (PDR) has taken a step forward. In the bandwidth of the Fourier Transform Spectrometer (FTS) of the Spectral and Photometric Imaging REceiver (SPIRE) on board Herschel, ten CO rotational transitions, including J=4-3 to J=13-12, and three fine structure lines, including [CI] 609, [CI] 370, and [NII] 250 micron, are covered. This presentation focuses on the physical conditions of molecular gas probed by the Herschel SPIRE/FTS.Based on the spatially resolved physical parameters derived from the CO spectral line energy distribution (SLED) map and the comparisons with the dust properties and star-formation tracers, I will first present our findings at the circumnuclear region of M83, and then zoom in toward the young open cluster, Trumpler 14, in Carina nebula. I will discuss (1) the potential of using [NII] 250 and [CI] 370 micron as star-formation tracers; (2) the reliability of tracing molecular gas with CO; (3) the excitation mechanisms of warm CO; (4) the possibility of studying stellar feedback by tracing the thermal pressure of intersetllar molecular gas.

  13. Bathyal suprabenthic assemblages from the southern margin of the Capbreton Canyon (“Kostarrenkala” area), SE Bay of Biscay

    NASA Astrophysics Data System (ADS)

    Frutos, Inmaculada; Sorbe, Jean Claude

    2014-06-01

    The bathyal suprabenthic fauna of the Kostarrenkala area (Capbreton Canyon, SE Bay of Biscay) was sampled during daytime at eight stations located on a bathymetric transect between 175 and 1000 m depth using a multinet suprabenthic sled. Two hundred and five suprabenthic taxa were recorded in this area, mainly amphipods, cumaceans, isopods and mysids. Total abundances ranged from 752 to 2640 ind./100 m2, showing a decreasing trend with depth. Diversity values (H‧) ranged between 3.83 and 5.72, increasing significantly with depth. Multivariate analysis of abundance data discriminated three assemblages according to depth: shelf break (72 sp., 1924 ind./100 m2), upper slope (93 sp., 1485 ind./100 m2) and mid slope (135 sp., 857 ind./100 m2) assemblages. Each assemblage was characterised by a distinct dominant species: the shelf amphipod Westwoodilla caecula at the shelf break, the isopod Munnopsurus atlanticus on muddy sand bottoms of the upper bathyal, and the amphipod Rhachotropis gracilis on mid-slope muddy bottoms below the mud line. Such a structure of bathyal assemblages seems to be generalised for the whole margin of the Bay of Biscay.

  14. Temporal changes in the structure of a slope suprabenthic community from the Bay of Biscay (NE Atlantic Ocean)

    NASA Astrophysics Data System (ADS)

    Sorbe, Jean Claude; Elizalde, Marta

    2014-08-01

    The suprabenthic community of the upper slope off Arcachon (site A at about 400 m depth on a muddy sand substratum) was sampled monthly from February 1991 to January 1992 with a suprabenthic sled towed over the sea bottom. The fauna collected in the 0-50 cm water layer above the bottom was classified into 9 major groups and 109 species (56 amphipods, 12 mysids, 10 isopods, 10 decapods, 9 cumaceans, 6 euphausiids, 4 fishes, 1 lophogastrid and 1 tanaid). The total abundance of the community fluctuated between a maximum of 3199 ind./100 m2 in July and a minimum of 82 ind./100 m2 in November, with an annual mean value of 969±601 ind./100 m2. The community structure was mainly affected by the temporal abundance fluctuations of the asellote isopod Munnopsurus atlanticus. This species was numerically dominant during the first part of the year and showed a drastic decrease in August, followed by the dominance of the mysids Erythrops neapolitana or Parapseudomma calloplura in autumn and early winter. Such structural changes in the dominance of major taxa are discussed with respect to the feeding behaviour of species and food availability in the near-bottom environment. We conclude that the population dynamics of M. atlanticus in the upper bathyal was mainly governed by the seasonal development of its major prey, the benthic foraminifers, favoured by the spring phytodetritus deposition on the sea floor.

  15. Precision 0.5 GW X-band rf system for advanced Compton scattering source

    NASA Astrophysics Data System (ADS)

    Chu, T. S.; Anderson, G.; Gibson, D.; Hartemann, F. V.; Barty, C. P. J.; Vlieks, A.; Tantawi, S.; Jongewaard, E.; Anderson, S. G.

    2009-11-01

    A Mono-Energetic Gamma-Ray (MEGa-Ray) Compton scattering light source is being developed at LLNL. The electron beam for the Compton scattering interaction will be generated by a X-band RF gun and a X-band LINAC at the frequency of 11.424 GHz. High power RF in excess of 500 MW is needed to accelerate the electrons to energy of 250 MeV or greater for the interaction. Two high power klystron amplifiers, each capable of generating 50 MW, 1.5 msec pulses, will be the main high power RF sources for the system. These klystrons will be powered by state of the art solid-state high voltage modulators. A RF pulse compressor, similar to the SLED II pulse compressor, will compress the klystron output pulse with a power gain factor of five. This will give us 500 MW (0.5 GW) at output of the compressor. The compressed pulse will then be distributed to the RF gun and to the LINAC with specific phase and amplitude control points to allow for parameter control during operation. This high power RF system is being designed and constructed. In this paper, we will present the design, layout, and status of this RF system.

  16. Bicycle helmet use and non-use - recently published research.

    PubMed

    Uibel, Stefanie; Müller, Daniel; Klingelhoefer, Doris; Groneberg, David A

    2012-01-01

    Bicycle traumata are very common and especially neurologic complications lead to disability and death in all stages of the life. This review assembles the most recent findings concerning research in the field of bicycle traumata combined with the factor of bicycle helmet use. The area of bicycle trauma research is by nature multidisciplinary and relevant not only for physicians but also for experts with educational, engineering, judicial, rehabilitative or public health functions. Due to this plurality of global publications and special subjects, short time reviews help to detect recent research directions and provide also information from neighbour disciplines for researchers. It can be stated that to date, that although a huge amount of research has been conducted in this area more studies are needed to evaluate and improve special conditions and needs in different regions, ages, nationalities and to create successful prevention programs of severe head and face injuries while cycling.Focus was explicit the bicycle helmet use, wherefore sledding, ski and snowboard studies were excluded and only one study concerning electric bicycles remained due to similar motion structures within this review. The considered studies were all published between January 2010 and August 2011 and were identified via the online databases Medline PubMed and ISI Web of Science. PMID:22632628

  17. Endocrine-disrupting compounds in reclaimed water and residential ponds and exposure potential for dislodgeable residues in turf irrigated with reclaimed water.

    PubMed

    Sidhu, Harmanpreet S; Wilson, Patrick C; O'Connor, George A

    2015-07-01

    Endocrine-disrupting chemicals (EDCs) occur in reclaimed water (RW), which may serve as an exposure source for humans. The presence of EDCs in RW used to irrigate turf and in nearby water-retention ponds was determined. In addition, the total dislodgeable mass of each EDC was determined after irrigation (using RW) to simulate exposure of a 3-year-child playing in turf grass recently irrigated with RW. Five EDCs (estrone, 17β-estradiol, 17α-ethynylestradiol, bisphenol A, and 4-n-nonylphenol) were quantified in 28 samples of RWs (wastewater-treatment plant effluents) and 88 samples from residential surface water-retention ponds. St. Augustine variety of turf grass was irrigated with spiked RW to study dislodgement of the five EDCs overtime using a drag-sled method. Grass clippings were analyzed to relate masses of EDC on grass with masses dislodged. EDCs were detected in both RW and ponds at ng/L concentrations. Maximum EDC masses were dislodged immediately after irrigation. Dislodged masses of estrone and 17β-estradiol are two separate EDCs, 17β-estradiol and 17α-ethynylestradiol decreased rapidly and were lower than detection limits 4 h after application. Dislodged bisphenol-A and nonylphenol decreased more slowly but were not detected 6 h after application. Avoiding contact with recently irrigated turf grass should decrease the risks of exposure to these EDCs. PMID:25758534

  18. Crashworthiness of Aluminium Tubes; Part 2: Improvement of Hydroforming Operation to Increase Absorption Energy

    SciTech Connect

    D'Amours, Guillaume; Rahem, Ahmed; Mayer, Robert; Williams, Bruce; Worswick, Michael

    2007-05-17

    The motivation to reduce overall vehicle weight within the automotive sector drives the substitution of lightweight materials such as aluminium alloys for structural components. Such a substitution requires a significant amount of development to manufacture structurally parts such that the energy absorption characteristics are not sacrificed in the event of crash. The effects of the manufacturing processes on the crash performance of automotive structural components must be better understood to ensure improved crashworthiness. This paper presents results of an experimental and numerical investigation of the crash response and energy absorption properties of impacted hydroformed aluminium alloy tubes. Crash experiments on hydroformed tubes were performed using a deceleration sled test at the General Motors Technical Center. Results from axial crush testing showed that an important parameter that influences the energy absorption characteristics during crash was the thickness reduction caused by circumferential expansion of the tube during hydroforming. It was found that that the energy absorption decreased as the corner radius decreased, which results because of increased thinning. Sensitivity studies of end feeding parameters, such as end feed level and profile, were carried out to evaluate their impact on the energy absorption of the aluminium tubes.

  19. Door Velocity and Occupant Distance Affect Lateral Thoracic Injury Mitigation with Side Airbag

    PubMed Central

    Hallman, Jason J; Yoganandan, Narayan; Pintar, Frank A

    2010-01-01

    The relationship between thoracic injury risk and parameters of door velocity and occupant distance was delineated in blunt lateral impact with side airbag deployment. A sled impact model was exercised with the validated MADYMO fiftieth percentile facet occupant model and a generalized finite element torso side airbag. Impact velocity was incremented from 4.0 to 9.0 m/s; occupant-airbag distance (at time of airbag activation) was incremented from 2.0 to 24.0 cm; simulations without airbag were also examined. Using compression, deflection rate, and the Viscous Criterion, airbag performance was characterized with respect to occupant injury risk at three points of interest: occupant distance of most protection, distance of greatest injury risk, and the newly defined critical distance. The occupant distance which demonstrated the most airbag protection, i.e., lowest injury risk, increased with increasing impact velocity. Greatest injury risk resulted when the occupant was nearest the airbag regardless of impact velocity. The critical distance was defined as the farthest distance at which airbag deployment exacerbated injury risk. This critical distance only varied considering chest compression, between 3 and 10 cm from the airbag, but did not vary when the Viscous Criterion were evaluated. At impact velocities less than or equal to 6 m/s, the most protective occupant location was within 2 cm of the critical distance at which the airbag became harmful. Therefore, injury mitigation with torso airbag may be more difficult to achieve at lower ΔV. PMID:21376873

  20. Single-shot depth-resolved displacement field measurement using phase-contrast polychromatic speckle interferometry

    NASA Astrophysics Data System (ADS)

    Ruiz, Pablo D.; de la Torre-Ibarra, Manuel; Huntley, Jonathan M.

    2006-09-01

    We describe a system for measuring sub-surface displacement fields within a scattering medium using a broadband super-luminescent light emitting diode (SLED) source and spectral imaging. The use of phase information in the backscattered speckle pattern offers displacement sensitivity in the range of a few tens of nm, some two to three orders of magnitude better than the depth resolution of state-of-the-art Optical Coherence Tomography systems. The system is based on low cost components and has no moving parts. It provides displacement maps within a 2-D slice extending into the sample, and the fact that all the data for a given deformation state are acquired in a single shot is a highly attractive feature for in-vivo investigations in the biological sciences. The theoretical basis for the system is presented along with experimental results from a simple well-controlled geometry consisting of independently-tilting glass sheets. Results are validated using standard two-beam interferometry. Scattering samples were also studied and we show a wrapped phase map through the thickness of a pig ex-vivo cornea. The phase change was due to viscoelastic creep in the cornea after a change in the intraocular pressure.

  1. Bicycle helmet use and non-use – recently published research

    PubMed Central

    2012-01-01

    Bicycle traumata are very common and especially neurologic complications lead to disability and death in all stages of the life. This review assembles the most recent findings concerning research in the field of bicycle traumata combined with the factor of bicycle helmet use. The area of bicycle trauma research is by nature multidisciplinary and relevant not only for physicians but also for experts with educational, engineering, judicial, rehabilitative or public health functions. Due to this plurality of global publications and special subjects, short time reviews help to detect recent research directions and provide also information from neighbour disciplines for researchers. It can be stated that to date, that although a huge amount of research has been conducted in this area more studies are needed to evaluate and improve special conditions and needs in different regions, ages, nationalities and to create successful prevention programs of severe head and face injuries while cycling. Focus was explicit the bicycle helmet use, wherefore sledding, ski and snowboard studies were excluded and only one study concerning electric bicycles remained due to similar motion structures within this review. The considered studies were all published between January 2010 and August 2011 and were identified via the online databases Medline PubMed and ISI Web of Science. PMID:22632628

  2. Feasibility study on conducting overflight measurements of shaped sonic boom signatures using the Firebee BQM-34E RPV

    NASA Technical Reports Server (NTRS)

    Maglieri, Domenic J.; Sothcott, Victor E.; Keefer, Thomas N., Jr.

    1993-01-01

    A study was performed to determine the feasibility of establishing if a 'shaped' sonic boom signature, experimentally shown in wind tunnel models out to about 10 body lengths, will persist out to representative flight conditions of 200 to 300 body lengths. The study focuses on the use of a relatively large supersonic remotely-piloted and recoverable vehicle. Other simulation methods that may accomplish the objective are also addressed and include the use of nonrecoverable target drones, missiles, full-scale drones, very large wind tunnels, ballistic facilities, whirling-arm techniques, rocket sled tracks, and airplane nose probes. In addition, this report will also present a background on the origin of the feasibility study including a brief review of the equivalent body concept, a listing of the basic sonic boom signature characteristics and requirements, identification of candidate vehicles in terms of desirable features/availability, and vehicle characteristics including geometries, area distributions, and resulting sonic boom signatures. A program is developed that includes wind tunnel sonic boom and force models and tests for both a basic and modified vehicles and full-scale flight tests.

  3. Brain Injury Differences in Frontal Impact Crash Using Different Simulation Strategies

    PubMed Central

    Li, Dao; Ma, Chunsheng; Shen, Ming; Li, Peiyu; Zhang, Jinhuan

    2015-01-01

    In the real world crashes, brain injury is one of the leading causes of deaths. Using isolated human head finite element (FE) model to study the brain injury patterns and metrics has been a simplified methodology widely adopted, since it costs significantly lower computation resources than a whole human body model does. However, the degree of precision of this simplification remains questionable. This study compared these two kinds of methods: (1) using a whole human body model carried on the sled model and (2) using an isolated head model with prescribed head motions, to study the brain injury. The distribution of the von Mises stress (VMS), maximum principal strain (MPS), and cumulative strain damage measure (CSDM) was used to compare the two methods. The results showed that the VMS of brain mainly concentrated at the lower cerebrum and occipitotemporal region close to the cerebellum. The isolated head modelling strategy predicted higher levels of MPS and CSDM 5%, while the difference is small in CSDM 10% comparison. It suggests that isolated head model may not equivalently reflect the strain levels below the 10% compared to the whole human body model. PMID:26495029

  4. Reproductive hormones during 42 days of maximal physical effort, low temperatures and general hardship.

    PubMed

    Johansen, A T; Norman, N

    1991-01-01

    Four well trained men crossed the inland glacier of Greenland in 1988, retracing the route of the famous arctic explorer Fridtjof Nansen from 1888. They used true copies of Nansen's equipment in all details. Each pulled at sled weighing 130 kg at the start. The expedition lasted 42 days, covered 500 km, highest point 2800 m above see level, coldest temperature -50 degrees C. Serum testosterone, sex hormone bindings globulin (SHBG), luteinizing hormone (LH), follicle stimulating hormone (FSH) and prolactine (PRL) were determined at weekly intervals, before, during and after this exceptionally long lasting, physically exhausting and stressful exercise. Testosterone fell to a mean level of 1.8, 2.8 and 3.8 nmol/l during the last two weeks of the expedition (p less than 0.001), and SHBG increased correspondingly from 26.7 nmol/l before start to more than 50 nmol/l (p less than 0.05). PRL levels were significantly decreased (p less than 0.005) at the time point when testosterone was maximally reduced. The normalization of testosterone following the expedition was associated with a significant increase in LH (p less than 0.05). In spite of low testosterone levels, lean body mass increased during the expedition in 3 of the participants. PMID:1811570

  5. Full-scale turbine-missile-casing tests. Final report. [PWR; BWR

    SciTech Connect

    Yoshimura, H.R.; Schamaun, J.T.

    1983-01-01

    Results are presented of two full-scale tests simulating the impact of turbine disk fragments on simple ring and shell structures that represent the internal stator blade ring and the outer housing of an 1800-rpm steam turbine casing. The objective was to provide benchmark data on both the energy-absorbing mechanisms of the impact process and, if breakthrough occured, the exit conditions of the turbine missile. A rocket sled was used to accelerate a 1527-kg (3366-lb) segment of a turbine disk, which impacted a steel ring 12.7 cm (5 in.) thick and a steel shell 3.2 cm (1.25 in.) thick. The impact velocity of about 150 m/s (492 ft/s) gave a missile kinetic energy corresponding to the energy of a fragment from a postulated failure at the design overspeed (120% of operating speed). Depending on the orientation of the missile at impact, the steel test structure either slowed the missile to 60% of its initial translational velocity or brought it almost to rest (an energy reduction of 65 and 100%, respectively). The report includes structural and finite element analysis and data interpretation, estimates of energy during impact, missile displacement and velocity histories, and selected strain gage data.

  6. A 12 GHz RF Power Source for the CLIC Study

    SciTech Connect

    Schirm, Karl; Curt, Stephane; Dobert, Steffen; McMonagle, Gerard; Rossat, Ghislain; Syratchev, Igor; Timeo, Luca; Haase, Andrew Jensen, Aaron; Jongewaard, Erik; Nantista, Christopher; Sprehn, Daryl; Vlieks, Arnold; Hamdi, Abdallah; Peauger, Franck; Kuzikov, Sergey; Vikharev, Alexandr; /Nizhnii Novgorod, IAP

    2012-07-03

    The CLIC RF frequency has been changed in 2008 from the initial 30 GHz to the European X-band 11.9942 GHz permitting beam independent power production using klystrons for CLIC accelerating structure testing. A design and fabrication contract for five klystrons at that frequency has been signed by different parties with SLAC. France (IRFU, CEA Saclay) is contributing a solid state modulator purchased in industry and specific 12 GHz RF network components to the CLIC study. RF pulses over 120 MW peak at 230 ns length will be obtained by using a novel SLED-I type pulse compression scheme designed and fabricated by IAP, Nizhny Novgorod, Russia. The X-band power test stand is being installed in the CLIC Test Facility CTF3 for independent structure and component testing in a bunker, but allowing, in a later stage, for powering RF components in the CTF3 beam lines. The design of the facility, results from commissioning of the RF power source and the expected performance of the Test Facility are reported.

  7. Influence of Active Muscle Contribution on the Injury Response of Restrained Car Occupants

    PubMed Central

    Bose, Dipan; Crandall, Jeff R.

    2008-01-01

    Optimal performance of adaptive restraint systems requires an accurate assessment of occupant parameters including physical properties and pre-collision behavior of the occupant. Muscle bracing, one of the key reflexive actions adopted by car occupants to mitigate the severity of an impending collision, is ignored in restraint designing since conventional human surrogate tools used for injury assessment due to collision loading provide limited insight into this effect. This study is aimed at evaluating the effect of pre-collision muscle bracing on the injury outcome of an occupant using a simplified numerical musculoskeletal model. The activation levels for 12 major muscle groups loading the ankle, knee, hip and elbow joints, were determined using an optimization routine with data collected from previously reported volunteer sled tests. A whole body injury metric, weighted to the severity of injury and the injured body region, was used to evaluate the potential risk of injuries estimated for different levels of bracing. The musculoskeletal model was further used to determine the requirements on the restraint system properties to minimize overall injuries for an occupant in a relaxed and a braced condition. Significant variation was observed in the load-limiting value and pre-tensioner firing time, as the restraint properties were optimized to account for the bracing behavior. The results of the study provide a framework for improving the performance of adaptive restraint systems, currently designed for passive anthropometric tests devices, by taking into account realistic response of the occupant involved in a collision. PMID:19026223

  8. Factors Influencing Occupant-To-Seat Belt Interaction in Far-Side Crashes

    PubMed Central

    Douglas, C.A.; Fildes, B.N.; Gibson, T.J.; Boström, O.; Pintar, F.A.

    2007-01-01

    Seat belt interaction with a far-side occupant’s shoulder and thorax is critical to governing excursion towards the struck-side of the vehicle in side impact. In this study, occupant-to-belt interaction was simulated using a modified MADYMO human model and finite element belts. Quasi-static tests with volunteers and dynamic sled tests with PMHS and WorldSID were used for model validation and comparison. Parameter studies were then undertaken to quantify the effect of impact direction, seat belt geometry and pretension on occupant-to-seat belt interaction. Results suggest that lowering the D-ring and increasing pretension reduces the likelihood of the belt slipping off the shoulder. Anthropometry was also shown to influence restraint provided by the shoulder belt. Furthermore, the belt may slip off the occupant’s shoulder at impact angles greater than 40 degrees from frontal when no pretension is used. However, the addition of pretension allowed the shoulder to engage the belt in all impacts from 30 to 90 degrees. PMID:18184500

  9. Biomechanical impact response of the human chin and manubrium.

    PubMed

    Stammen, Jason A; Bolte, John H; Shaw, Joshua

    2012-03-01

    Chin-to-chest impact commonly occurs in frontal crash simulations with restrained anthropomorphic test devices (ATDs) in non-airbag situations. This study investigated the biofidelity of this contact by evaluating the impact response of both the chin and manubrium of adult post-mortem human subjects (PMHSs). The adult PMHS data were scaled to a 10-year-old (YO) human size and then compared with the Hybrid III 10YO child (HIII-10C) ATD response with the same test configurations. For both the chin and manubrium, the responses of the scaled PMHS had different characteristics than the HIII-10C ATD responses. Elevated energy impact tests to the PMHS mandible provided a mean injury tolerance value for chin impact force. Chin contact forces in the HIII-10C ATD were calculated in previously conducted HYGE sled crash simulation tests, and these contact forces were strongly correlated with the Head Injury Criterion (HIC(36 ms)). The mean injurious force from the PMHS tests corresponded to a HIC(36 ms) value that would predict an elevated injury risk if it is assumed that fractures of the chin and skull are similarly correlated with HIC(36 ms). Given the rarity of same occupant-induced chin injury in booster-seated occupants in real crash data and the disparity in chin and manubrium stiffnesses between scaled PMHS and HIII-10C ATD, the data from this study can be made use of to improve biofidelity of chin-to-manubrium contact in ATDs. PMID:21971966

  10. Effects of Droplet Size on Intrusion of Sub-Surface Oil Spills

    NASA Astrophysics Data System (ADS)

    Adams, Eric; Chan, Godine; Wang, Dayang

    2014-11-01

    We explore effects of droplet size on droplet intrusion and transport in sub-surface oil spills. Negatively buoyant glass beads released continuously to a stratified ambient simulate oil droplets in a rising multiphase plume, and distributions of settled beads are used to infer signatures of surfacing oil. Initial tests used quiescent conditions, while ongoing tests simulate currents by towing the source and a bottom sled. Without current, deposited beads have a Gaussian distribution, with variance increasing with decreasing particle size. Distributions agree with a model assuming first order particle loss from an intrusion layer of constant thickness, and empirically determined flow rate. With current, deposited beads display a parabolic distribution similar to that expected from a source in uniform flow; we are currently comparing observed distributions with similar analytical models. Because chemical dispersants have been used to reduce oil droplet size, our study provides one measure of their effectiveness. Results are applied to conditions from the `Deep Spill' field experiment, and the recent Deepwater Horizon oil spill, and are being used to provide ``inner boundary conditions'' for subsequent far field modeling of these events. This research was made possible by grants from Chevron Energy Technology Co., through the Chevron-MITEI University Partnership Program, and BP/The Gulf of Mexico Research Initiative, GISR.

  11. The impact of relative intensity noise on the signal in multiple reference optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Neuhaus, Kai; Subhash, Hrebesh; Alexandrov, Sergey; Dsouza, Roshan; Hogan, Josh; Wilson, Carol; Leahy, Martin; Slepneva, Svetlana; Huyet, Guillaume

    2016-03-01

    Multiple reference optical coherence tomography (MR-OCT) applies a unique low-cost solution to enhance the scanning depth of standard time domain OCT by inserting an partial mirror into the reference arm of the interferometric system. This novel approach achieves multiple reflections for different layers and depths of an sample with minimal effort of engineering and provides an excellent platform for low-cost OCT systems based on well understood production methods for micro-mechanical systems such as CD/DVD pick-up systems. The direct integration of a superluminescent light-emitting diode (SLED) is a preferable solution to reduce the form- factor of an MR-OCT system. Such direct integration exposes the light source to environmental conditions that can increase fluctuations in heat dissipation and vibrations and affect the noise characteristics of the output spectrum. This work describes the impact of relative intensity noise (RIN) on the quality of the interference signal of MR-OCT related to a variety of environmental conditions, such as temperature.

  12. Dorsal light response and changes of its responses under varying acceleration conditions

    NASA Astrophysics Data System (ADS)

    Watanabe, S.; Takabayashi, A.; Takagi, S.; von Baumgarten, R.; Wetzig, J.

    In order to improve our understanding about functions of the gravity sensors, we have conducted four experiments in goldfish: 1) To define the effect of visual information influx on the static labyrinthine response, the dorsal light response (DLR) which had been proposed by von Holst as a model for postural adjustment in fish was reexamined with a newly designed, rotatory illumination device. The fish responded to illumination from the upper half of the visual field and a narrow range around 180 degrees of the lower half visual field. The maximal tilting angle of normal fish was about 40 degrees under horizontal illumination. 2) Under the changes of the gravito-inertial force level produced by a linear sled, the threshold of the gravity sensors was determined from postural adjustment responses. 3) Under hypogravic conditions during the parabolic flight of an airplane, the light-dependent behavior was investigated in intact and labyrinthectomized goldfish. 4) As one of the most likely candidates of the neural centers for the DLR, the valvula cerebelli, which receives its visual information not through the optic tectum but through the pretectal areas, is confirmed by the brain lesion experiments.

  13. Redshift Determination and 12CO Line Excitation Modeling for the Multiply-Lensed Submillimeter Galaxy SMM 1057+5730

    NASA Astrophysics Data System (ADS)

    Scott, Kimberly S.; Z-Spec Team; HerMES Consortium; IRAM PdBI Team; CARMA Team

    2011-01-01

    We report a redshift of z=2.956 for SMM 1057+5730, a multiply-lensed sub-millimeter galaxy detected with Herschel/SPIRE in the HerMES Lockman-SWIRE field. With the 100 GHz instantaneous bandwidth of the Z-Spec instrument on the Caltech Submillimeter Observatory, we robustly identify the redshift of this source from the simultaneous detection of four 12CO emission lines (J = 7-6, J = 8-7, J = 9-8, and J = 10-9). Combining the measured line fluxes for these high-J transitions with the J = 3-2 and J = 5-4 line fluxes measured with CARMA and the IRAM PdBI, respectively, we model the physical properties of the molecular gas in this galaxy. We find that the full 12CO spectral line energy distribution is best described by warm, low-density gas (T 400 K, n 102.7 cm-3). However, it is possible that the highest J transitions are radiatively excited by warm gas (potentially close to an AGN), or alternatively are tracing a small fraction of very dense gas in molecular cloud cores, which in either case a single gas component model would not describe the full SLED. Future observations of lower J transitions for this source will aid in distinguishing between these scenarios.

  14. Multi-color coronagraph experiments with binary-shaped pupil masks

    NASA Astrophysics Data System (ADS)

    Haze, Kanae; Enya, Keigo; Kotani, Takayuki; Abe, Lyu; Nakagawa, Takao; Higuchi, Shin; Sato, Toshimichi; Wakayama, Takayuki; Yamamuro, Tomoyasu

    We present results of our laboratory experiment on a binary-shaped pupil mask coronagraph for the direct observation of exoplanets. One of the methods to improve the enormous contrast between the central star and the planet is a stellar coronagraph. The coronagraph can change the PSF and reduce the gap of luminosity between an extra-solar planet and its central star. We focused on binary shaped pupil coronagraph that is planned to be installed in next-generation infrared space telescope SPICA. We are now conducting demonstration experiments to verify the effectiveness of the coronagraph. A contrast of 7.8 × 10-9 was achieved by the PSF sub-traction as the results of our laboratory experiments using He-Ne laser on the coronagraph which was implemented inside a vacuum chamber in order to achieve higher thermal stability and to avoid air turbulence. Furthermore, we carried out multi-color experiment using a Super luminescent Light Emitting Diode (SLED), with wavelengths of 650nm, 750nm, 800nm and 850nm. Additionally, we undertake development of the low-temperature vacuum chamber for the laboratory coronagraph experiment with mid-infrared range.

  15. Completing the CO spectral line energy distribution for luminous starburst galaxies discovered with the SPT

    NASA Astrophysics Data System (ADS)

    Aravena, Manuel; Weiss, Axel; de Breuck, Carlos; Stark, Antony A.; Marrone, Dan; McIntyre, Vince; Vieira, Joaquin; Greve, Thomas; Chapman, Scott; Murphy, Eric; Aguirre, James; Bothwell, Matt; Gullberg, Bitten

    2013-04-01

    We propose to use ATCA to observe the CO J=3-2 line emission in three gravitationally lensed, highly magnified dusty star-forming galaxies at z~2.5 discovered by the South Pole Telescope (SPT) millimeter survey. The redshifts of all targets were identified by the detection of several J>6 CO emission lines with APEX/Z-Spec and confirmed with VLT optical spectroscopy. Two of the sources have significant detections of the CO 1-0 line with ATCA, while CO 1-0 observations of the other source are being requested in a companion proposal. The proposed observations are critical to complete the CO spectral energy distribution (SLED) of these sources and thus "fill the gap" between the high-J CO observed with APEX/Z-Spec and the CO 1-0 line detected with ATCA. This will allow us to constrain the physical conditions of the interstellar medium by comparing the line strengths with large velocity gradient models. The strong magnification is key, allowing us to characterize the CO emission in galaxies that would be otherwise hard to detect.

  16. OT1_ppapadop_1: Strong AGN feedback onto the ISM and its effects: A SPIRE FTS view of the molecular gas in 3C293

    NASA Astrophysics Data System (ADS)

    Papadopoulos, P.

    2010-07-01

    We propose to use the SPIRE FTS to study the large molecular gas reservoir of the powerful radio galaxy 3C293, the scene of a very strong AGN jet-gas interaction, and the first known case of shock-powered luminous mid-J/high-J CO lines. These were discovered during our large ground-based CO line survey of Luminous Infrared Galaxies (LIRGs) and AGN hosts, and set this object apart as that with the most excited molecular gas of the entire survey, yet with its large gas reservoir (~2x10^9Msol) surprisingly idle in terms of star formation rate (SFR~4Msol/yr). A deep SPIRE FTS spectrum will complete our ground-based CO Spectral Line Energy Distribution (SLED) of this remarkable system and allow excellent constraints to be placed on the thermal state of its molecular gas reservoir and possible suppressing effects of the AGN on star formation in the host galaxy. It will also be the first opportunity to study, locally, powerful AGN mechanical feedback onto the interstellar medium of host galaxies, which will occur frequently in the Early Universe during galaxy formation in the deep gravitational wells of proto-clusters marked by such powerful radio galaxies.

  17. [CI] and CO in local galaxies from the Beyond the Peak Project

    NASA Astrophysics Data System (ADS)

    Crocker, Alison F.; Pellegrini, E. W.; Smith, J. T.; Beyond The Peak Team

    2014-01-01

    From simple plane-parallel photodissociation region (PDR) models, neutral carbon ([CI]) is predicted to exist in a thin layer between C+ and CO on the surface of molecular clouds (e.g. (Hollenbach & Tielens 1999, Kaufman et al. 1999). However, observations of the Milky Way and the Magellanic Clouds indicate that [CI] may instead be a better tracer of the entire cold gas reservoir, often very well correlated with emission from 12CO(1-0) or 13CO(1-0) (e.g. Keene et al. 1996, Bolatto et al. 2000, Shimajiri et al. 2013). Here, we present the observed [CI] fluxes from the Beyond the Peak sample of 22 nearby galaxies observed with the Herschel FTS spectrometer. We first attempt to model all CO transitions and the [CI] lines as a single plane-parallel PDR, but this fails in all cases. Instead, a two-component PDR model is able to fit the CO SLED of nearly all galaxies. We investigate correlations of the [CI] fluxes and line ratio with properties of the cooler component determined from the PDR fits.

  18. RLV Hopper: Consolidated System Concept

    NASA Astrophysics Data System (ADS)

    Spies, J.

    2002-01-01

    The Hopper, a concept for a reusable launch system was developed and found attractive in the frame of FESTIP, ESA's Future European Space Transportation Initiation Programme. Later, in the national German ASTRA programme the Hopper concept was adapted to newly emerged requirements and subjected to a detailed design loop. Taking off horizontally and staging at high sub-orbital velocity, the Hopper needs a rail-guided launch sled, downrange landing, re-transportation back to the launch site, and one, but only one upper stage. Horizontal take-off is used to improve safety and to reduce thrust requirement, and number mass and cost of main engines, and also problems with vehicle centring. Transportation of the cargo (e.g. payload and expendable upper stage) in the RLV reduces the number of the aerodynamically affected flight configurations to one. Staging at high sub-orbital velocity above the sensible atmosphere enables the use of only one standardised upper stage for all missions. Using a cryogenic upper stage the Hopper system is nearly optimally staged for the dimensioning GTO mission. The paper describes the consolidated Hopper system concept and highlights areas of special interest, evolution potential, and further steps.

  19. Highly Reusable Space Transportation System Concept Evaluation (The Argus Launch Vehicle)

    NASA Technical Reports Server (NTRS)

    Olds, John R.; Bellini, Peter X.

    1998-01-01

    This paper summarizes the results of a conceptual design study that was performed in support of NASA's recent Highly Reusable Space Transportation study. The Argus concept uses a Maglifter magnetic-levitation sled launch assist system to accelerate it to a takeoff ground speed of 800 fps on its way to delivering a payload of 20,000 lb. to low earth orbit. Main propulsion is provided by two supercharged ejector rocket engines. The vehicle is autonomous and is fully reusable. A conceptual design exercise determined the vehicle gross weight to be approximately 597,250 lb. and the dry weight to be 75,500 lb. Aggressive weight and operations cost assumptions were used throughout the design process consistent with a second-generation reusable system that might be deployed in 10-15 years. Drawings, geometry, and weight of the concept are included. Preliminary development, production, and operations costs along with a business scenario assuming a price-elastic payload market are also included. A fleet of three Argus launch vehicles flying a total of 149 flights per year is shown to have a financial internal rate of return of 28%. At $169/lb., the recurring cost of Argus is shown to meet the study goal of $100/lb.-$200/lb., but optimum market price results in only a factor of two to five reduction compared to today's launch systems.

  20. FERROELECTRIC SWITCH FOR A HIGH-POWER Ka-BAND ACTIVE PULSE COMPRESSOR

    SciTech Connect

    Hirshfield, Jay L.

    2013-12-18

    Results are presented for design of a high-power microwave switch for operation at 34.3 GHz, intended for use in an active RF pulse compressor. The active element in the switch is a ring of ferroelectric material, whose dielectric constant can be rapidly changed by application of a high-voltage pulse. As envisioned, two of these switches would be built into a pair of delay lines, as in SLED-II at SLAC, so as to allow 30-MW μs-length Ka-band pulses to be compressed in time by a factor-of-9 and multiplied in amplitude to generate 200 MW peak power pulses. Such high-power pulses could be used for testing and evaluation of high-gradient mm-wave accelerator structures, for example. Evaluation of the switch design was carried out with an X-band (11.43 GHz) prototype, built to incorporate all the features required for the Ka-band version.

  1. Head and neck response of a finite element anthropomorphic test device and human body model during a simulated rotary-wing aircraft impact.

    PubMed

    White, Nicholas A; Danelson, Kerry A; Gayzik, F Scott; Stitzel, Joel D

    2014-11-01

    A finite element (FE) simulation environment has been developed to investigate aviator head and neck response during a simulated rotary-wing aircraft impact using both an FE anthropomorphic test device (ATD) and an FE human body model. The head and neck response of the ATD simulation was successfully validated against an experimental sled test. The majority of the head and neck transducer time histories received a CORrelation and analysis (CORA) rating of 0.7 or higher, indicating good overall correlation. The human body model simulation produced a more biofidelic head and neck response than the ATD experimental test and simulation, including change in neck curvature. While only the upper and lower neck loading can be measured in the ATD, the shear force, axial force, and bending moment were reported for each level of the cervical spine in the human body model using a novel technique involving cross sections. This loading distribution provides further insight into the biomechanical response of the neck during a rotary-wing aircraft impact. PMID:25085863

  2. Tracing the origin of Geodynamics: The Alfred Wegener Memorial Expedition 2014

    NASA Astrophysics Data System (ADS)

    Stüwe, Kurt

    2015-04-01

    2012 marked the 100st anniversary of the seminal publications on Continental Drift Theory by Alfred Wegener. These publications (and Wegener's book "On the origin of the continents", published three years later) are widely accepted to be the fundamental breakthrough that opened the path to the Theory of Plate Tectoncis and ultimately the path to modern Geodynamics some 50 years later. In the same historic year of the 1912 publications, Alfred Wegener set off for what was to become the most dramatic of his three Greenland expeditions. On this expedition Wegener and Koch crossed the entire northern icecap of Greenland. In honour of the hundreds anniversary of Wegener's publications, the Austrian Academy of Sciences funded an expedition to trace the footsteps of the 1912 expedition in the spirit of Alfred Wegener, while also conducting modern Earth Science. This expedition that was conducted in summer 2014. For the expedition, a 1952 Cessna180 was acquired in Alaska, adapted with bush wheels, wing extensions and extra tanks and was flown by the author and one of the worlds most renown bush pilots from Alaska in a 10 day effort to Greenland. There, the entire NE Greenland Caledonides were covered and photographed. Field work for a masters projects was conducted and samples were collected from a series of some of the most remote locations in the Caledonides ever visited. Most spectacularly, the original sled of Wegeners 1912 expedition was found some 30 kilometers from its expected location in the Dove Bugt Region of northeastern Greenland.

  3. Feasibility study on linear-motor-assisted take-off (LMATO) of winged launch vehicle

    NASA Astrophysics Data System (ADS)

    Nagatomo, Makoto; Kyotani, Yoshihiro

    1987-11-01

    Application of technology of magnetically levitated transportation to horizontal take-off of an experimental space vehicle has been studied. An experimental system of linear-motor-assisted take-off (LMATO) consists of the HIMES space vehicle and a magnetically levitated and propelled sled which is a modified MLU model developed by the JNR. The original MLU model is a train of three cars which weighs 30 tons and is driven by a thrust of 15 tons. The maximum speed is 400 km/h. The highest speed of 517 km/h has been obtained by the first JNR linear motor car. Since the take-off speed of the HIMES vehicle with the initial mass of 14 tons is 470 km/h, the existing technology can be used for the LMATO of the vehicle. The concept of the HIMES/LMATO is to use the MLU vehicles to accelerate the HIMES vehicle at 0.33 g on a 5 km guide track until the speed reaches 300 km/h, when the rocket engines of the space vehicle are started to increase the acceleration up to 1 g. The total system will take the final checkout for take-off during the acceleration phase and the speed exceeds 470 km/h which is large enough to aerodynamically lift the space vehicle, then the fastening mechanism is unlocked to separate the vehicles. The experimental system can be applied for initial acceleration of a vehicle with air-breathing propulsion.

  4. [The inversion processing of vegetation biomass along Yongding River based on multispectral information].

    PubMed

    He, Cheng; Feng, Zhong-Ke; Han, Xu; Sun, Meng-Ying; Gong, Yin-Xi; Gao, Yuan; Dong, Bin

    2012-12-01

    Researching on vegetation biomass using the traditional measurement method is time-consuming and hard sledding, and prediction precision of biomass is always not good because of uncertain influencing factors. The present article aims at the current situation of Hebei-Beijing reach along Yongding River, using the Thematic Mapper data in this place on 20th July 2009 as source data, with the 30 meters Digital Elevation Model data in Beijing and other auxiliary information, meanwhile through field observation data, to find out the possible functional relationship along vegetation biomass and remote sensing image factor. The authros sorted out the vegetation biomass and remote sensing image factor on the sample plot, then set up an inverse model through multiple linear regression analysis, and analyzed the precision of inverse model. After calculating the measured value and predicted value, the authors got the global relative error is -0.025%, the average relative error is -0.016%, and the general predictive precision is 84.56%. The establishment of this model is able to investigate eco-environmental factors on large range timely, quickly and accurately, also can provide the experimental base for the eco-environmental survey on river basin, and make the foundation for the problem diagnosis of ecological environment and the research on ecosystem degradation mechanism of Yongding River. PMID:23427566

  5. Brain Injury Differences in Frontal Impact Crash Using Different Simulation Strategies.

    PubMed

    Li, Dao; Ma, Chunsheng; Shen, Ming; Li, Peiyu; Zhang, Jinhuan

    2015-01-01

    In the real world crashes, brain injury is one of the leading causes of deaths. Using isolated human head finite element (FE) model to study the brain injury patterns and metrics has been a simplified methodology widely adopted, since it costs significantly lower computation resources than a whole human body model does. However, the degree of precision of this simplification remains questionable. This study compared these two kinds of methods: (1) using a whole human body model carried on the sled model and (2) using an isolated head model with prescribed head motions, to study the brain injury. The distribution of the von Mises stress (VMS), maximum principal strain (MPS), and cumulative strain damage measure (CSDM) was used to compare the two methods. The results showed that the VMS of brain mainly concentrated at the lower cerebrum and occipitotemporal region close to the cerebellum. The isolated head modelling strategy predicted higher levels of MPS and CSDM 5%, while the difference is small in CSDM 10% comparison. It suggests that isolated head model may not equivalently reflect the strain levels below the 10% compared to the whole human body model. PMID:26495029

  6. A search for the effects exerted by a possible Martian intrinsic magnetic field on its SEP environment

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, Susan; Alho, Markku; Kallio, Esa; Jarvinen, Riku; Dyadechkin, Sergey; Wedlund, Cyril Simon

    2014-05-01

    Present-day Mars does not have a significant global intrinsic magnetic field although it displays surface magnetic anomalies. In the past 'young Mars' may have had a strong intrinsic magnetic field. Induced Martian magnetic fields affect the properties of Solar Energetic Particles, (SEPs), near the planet. Recent Martian SEP environment studies, made using self-consistent global plasma simulations [McKenna-Lawlor et al. 2012; Kallio et al., 2012], have shown that piled up magnetic fields in the Martian magnetosheath/magnetosphere affect the behaviour of SEPs, resulting, for instance, in dramatic magnetic shadowing. In these studies when correlating the simulations with in situ measurements made by the SLED instrument aboard the Phobos spacecraft, Mars was not assumed to have an intrinsic magnetic field, which raises the question as to whether, and how, a residual Martian intrinsic magnetic field may have contributed to affecting the disturbed solar energetic particles (SEPs) recorded near the planet. In the present work we have extended our hybrid modelling of SEPs by assuming that Mars has an intrinsic magnetic field. Then, we compare a non-magnetized Mars with a magnetized Mars in terms of SEP measurements. We also discuss the consequences of the results, keeping in mind the forthcoming in situ SEP instrument measurements which are scheduled to start near Mars at the end of 2014 on-board the MAVEN spacecraft.

  7. Environmental assessment of general-purpose heat source safety verification testing

    SciTech Connect

    1995-02-01

    This Environmental Assessment (EA) was prepared to identify and evaluate potential environmental, safety, and health impacts associated with the Proposed Action to test General-Purpose Heat Source (GPHS) Radioisotope Thermoelectric Generator (RTG) assemblies at the Sandia National Laboratories (SNL) 10,000-Foot Sled Track Facility, Albuquerque, New Mexico. RTGs are used to provide a reliable source of electrical power on board some spacecraft when solar power is inadequate during long duration space missions. These units are designed to convert heat from the natural decay of radioisotope fuel into electrical power. Impact test data are required to support DOE`s mission to provide radioisotope power systems to NASA and other user agencies. The proposed tests will expand the available safety database regarding RTG performance under postulated accident conditions. Direct observations and measurements of GPHS/RTG performance upon impact with hard, unyielding surfaces are required to verify model predictions and to ensure the continual evolution of the RTG designs that perform safely under varied accident environments. The Proposed Action is to conduct impact testing of RTG sections containing GPHS modules with simulated fuel. End-On and Side-On impact test series are planned.

  8. The ecosystem service value of living versus dead biogenic reef

    NASA Astrophysics Data System (ADS)

    Sheehan, E. V.; Bridger, D.; Attrill, M. J.

    2015-03-01

    Mixed maerl beds (corralline red algae) comprise dead thalli with varying amounts of live maerl fragments, but previously it was not known whether the presence of the live maerl increases the ecosystem service 'habitat provision' of the dead maerl for the associated epibenthos. A 'flying array' towed sled with high definition video was used to film transects of the epibenthos in dead maerl and mixed maerl beds in two locations to the north and south of the English Channel (Falmouth and Jersey). Mixed maerl beds supported greater number of taxa and abundance than dead beds in Falmouth, while in Jersey, mixed and dead beds supported similar number of taxa and dead beds had a greater abundance of epifauna. Scallops tended to be more abundant on mixed beds than dead beds. Tube worms were more abundant on mixed beds in Falmouth and dead beds in Jersey. An increasing percentage occurrence of live maerl thalli correlated with increasing number of taxa in Falmouth but not Jersey. It was concluded that while live thalli can increase the functional role of dead maerl beds for the epibenthos, this is dependent on location and response variable. As a result of this work, maerl habitat in SE Jersey has been protected from towed demersal fishing gear.

  9. HEGRS: Mechanical design of a high-energy, gamma-ray spectrometer

    SciTech Connect

    Pedersen, K.B.

    1993-06-04

    A large, 3200-kg (7000-lb) gamma-ray spectrometer was designed to move in a 1500 arc with an arc accuracy of 0.50, and to move radially over a distance of 650 mm (25 in.). The entire structure is aluminum rather than steel because of the high neutron background. The two-layer support accommodates rapid, accurate positioning of the spectrometer in both the rotational and radial directions within 0.1 mm (0.004 in.). All movements and positioning are computer-controlled. The centerline deviation over the entire surface is 0.25 mm (0.0100 in.). The bottom layer, called the table, permits arc motion. The table is a baseplate consisting of two 3.6-m {times} 1.2-m (12-ft {times} 4-ft) cast-aluminum jig plates. The top layer, called the sled, is an aluminum plate 2.12-m {times} 1.22-m (83.38-in. {times} 48-in.) wide, which provides for radial motion. Due to the large mass of the spectrometer and the accurate positioning required, air pads are used to facilitate movement. Hydraulic brakes are applied when the detector is in its rest position to comply with the seismic requirements of the installation.

  10. Mission planning for space based satellite surveillance experiments with the MSX

    NASA Technical Reports Server (NTRS)

    Sridharan, R.; Fishman, T.; Robinson, E.; Viggh, H.; Wiseman, A.

    1994-01-01

    The Midcourse Space Experiment is a BMDO-sponsored scientific satellite set for launch within the year. The satellite will collect phenomenology data on missile targets, plumes, earth limb backgrounds and deep space backgrounds in the LWIR, visible and ultra-violet spectral bands. It will also conduct functional demonstrations for space-based space surveillance. The Space-Based Visible sensor, built by Lincoln Laboratory, Massachusetts Institute of Technology, is the primary sensor on board the MSX for demonstration of space surveillance. The SBV Processing, Operations and Control Center (SPOCC) is the mission planning and commanding center for all space surveillance experiments using the SBV and other MSX instruments. The guiding principle in the SPOCC Mission Planning System was that all routine functions be automated. Manual analyst input should be minimal. Major concepts are: (I) A high level language, called SLED, for user interface to the system; (2) A group of independent software processes which would generally be run in a pipe-line mode for experiment commanding but can be run independently for analyst assessment; (3) An integrated experiment cost computation function that permits assessment of the feasibility of the experiment. This paper will report on the design, implementation and testing of the Mission Planning System.

  11. Design, integration, and testing of a compact FBG interrogator, based on an AWG spectrometer

    NASA Astrophysics Data System (ADS)

    Trita, Andrea; Vickers, Garrie; Mayordomo, Iker; van Thourhout, Dries; Vermeiren, Jan

    2014-05-01

    Fiber Bragg Grating or FBG sensors are gaining more and more interest in structural health monitoring of composite materials. Often, the weakest point in such a system is the ingress point of the fiber sensing chain into the composite material. For this reason we have developed a strongly miniaturized FBG interrogator unit with wireless power and data transmission, which can be incorporated in the composite structure. The interrogator is based on an arrayed waveguide grating (AWG) filter fabricated in a SOI technology, which is tailored in such a way to give large cross-talk between neighboring channels. The AWG signals are read by a linear 128 pixel InGaAs array flip-chipped on top of the Photonic Circuit (PIC). The spectrometer unit is completed with a ROIC mounted on the same substrate. The SLED and remaining electronics are integrated on a small and thin substrate and surrounded by the wireless antenna. The interrogator has an overall dimension of 100 mm diameter by max 7 mm height. The power dissipation of the electronics unit is limited to 1.5 W. The unit is capable of measuring strain values as low as 5 micro-strain.

  12. Illustrations of the importance of mass wasting in the evolution of continental margins

    SciTech Connect

    Pratson, L.; Ryan, W. ); Twichell, D. )

    1990-05-01

    Side-looking sonar imagery and swath bathymetry from a variety of contemporary continental slopes all display erosional scars and debris aprons, illustrating the importance of mass wasting in the evolution of continental margins. The continental slopes examined include slopes fed directly from the fronts of ice sheets, slopes adjacent to continental shelves that were the sites of glacial outwash, slopes supplied exclusively by fluvial drainage, slopes at carbonate platforms, and slopes on accretionary prisms. Examples are drawn from the Atlantic Ocean, the Gulf of Mexico, and the Mediterranean Sea in both passive and active continental margin settings. The sonar imagery and bathymetry used in this study indicate that continental slopes in different tectonic and climatic environments show similar forms of mass wasting. However, in some cases the dominant mode of erosion and/or the overall degree of mass wasting appears to be distinct to particular sedimentary environments. Timing of both recent and older exhumed erosional surfaces identified in the imagery and in seismic reflection profiles is obtained by ground truth observations using submersibles, towed camera sleds, drilling, and coring. These observations suggest that eustatic fluctuations common to all the margins examined do not explain the range in magnitude and areal density of the observed mass wasting. More localized factors such as lithology, diagenesis, pore fluid conditions, sediment supply rates, and seismic ground motion appear to have a major influence in the evolution of erosional scars and their corresponding unconformities.

  13. Test Report for Perforated Metal Air Transportable Package (PMATO) Prototype.

    SciTech Connect

    Bobbe, Jeffery G.; Pierce, Jim Dwight

    2003-06-01

    A prototype design for a plutonium air transport package capable of carrying 7.6 kg of plutonium oxide and surviving a ''worst-case'' plane crash has been developed by Sandia National Laboratories (SNL) for the Japan Nuclear Cycle Development Institute (JNC). A series of impact tests were conducted on half-scale models of this design for side, end, and comer orientations at speeds close to 282 m/s onto a target designed to simulate weathered sandstone. These tests were designed to evaluate the performance of the overpack concept and impact-limiting materials in critical impact orientations. The impact tests of the Perforated Metal Air Transportable Package (PMATP) prototypes were performed at SNL's 10,000-ft rocket sled track. This report describes test facilities calibration and environmental testing methods of the PMATP under specific test conditions. The tests were conducted according to the test plan and procedures that were written by the authors and approved by SNL management and quality assurance personnel. The result of these tests was that the half-scale PMATP survived the ''worst-case'' airplane crash conditions, and indicated that a full-scale PMATP, utilizing this overpack concept and these impact-limiting materials, would also survive these crash conditions.

  14. Long-term change in benthopelagic fish abundance in the abyssal northeast Pacific Ocean.

    PubMed

    Bailey, D M; Ruhl, H A; Smith, K L

    2006-03-01

    Food web structure, particularly the relative importance of bottom-up and top-down control of animal abundances, is poorly known for the Earth's largest habitats: the abyssal plains. A unique 15-yr time series of climate, productivity, particulate flux, and abundance of primary consumers (primarily echinoderms) and secondary consumers (fish) was examined to elucidate the response of trophic levels to temporal variation in one another. Towed camera sled deployments in the abyssal northeast Pacific (4100 m water depth) showed that annual mean numbers of the dominant fish genus (Coryphaenoides spp.) more than doubled over the period 1989-2004. Coryphaenoides spp. abundance was significantly correlated with total abundance of mobile epibenthic megafauna (echinoderms), with changes in fish abundance lagging behind changes in the echinoderms. Direct correlations between surface climate and fish abundances, and particulate organic carbon (POC) flux and fish abundances, were insignificant, which may be related to the varied response of the potential prey taxa to climate and POC flux. This study provides a rare opportunity to study the long-term dynamics of an unexploited marine fish population and suggests a dominant role for bottom-up control in this system. PMID:16602284

  15. Mission planning for space based satellite surveillance experiments with the MSX

    NASA Astrophysics Data System (ADS)

    Sridharan, R.; Fishman, T.; Robinson, E.; Viggh, H.; Wiseman, A.

    1994-11-01

    The Midcourse Space Experiment is a BMDO-sponsored scientific satellite set for launch within the year. The satellite will collect phenomenology data on missile targets, plumes, earth limb backgrounds and deep space backgrounds in the LWIR, visible and ultra-violet spectral bands. It will also conduct functional demonstrations for space-based space surveillance. The Space-Based Visible sensor, built by Lincoln Laboratory, Massachusetts Institute of Technology, is the primary sensor on board the MSX for demonstration of space surveillance. The SBV Processing, Operations and Control Center (SPOCC) is the mission planning and commanding center for all space surveillance experiments using the SBV and other MSX instruments. The guiding principle in the SPOCC Mission Planning System was that all routine functions be automated. Manual analyst input should be minimal. Major concepts are: (I) A high level language, called SLED, for user interface to the system; (2) A group of independent software processes which would generally be run in a pipe-line mode for experiment commanding but can be run independently for analyst assessment; (3) An integrated experiment cost computation function that permits assessment of the feasibility of the experiment. This paper will report on the design, implementation and testing of the Mission Planning System.

  16. 500 MW X-Band RF System of a 0.25 GeV Electron LINAC for Advanced Compton Scattering Source Application

    SciTech Connect

    Chu, Tak Sum; Anderson, Scott; Barty, Christopher; Gibson, David; Hartemann, Fred; Marsh, Roark; Siders, Craig; Adolphsen, Chris; Jongewaard, Erik; Raubenheimer, Tor; Tantawi, Sami; Vlieks, Arnold; Wang, Juwen; /SLAC

    2012-07-03

    A Mono-Energetic Gamma-Ray (MEGa-Ray) Compton scattering light source is being developed at LLNL in collaboration with the SLAC National Accelerator Laboratory. The electron beam for the Compton scattering interaction will be generated by a X-band RF gun and a X-band LINAC at the frequency of 11.424 GHz. High power RF in excess of 500 MW is needed to accelerate the electrons to energy of 250 MeV or greater for the interaction. Two high power klystron amplifiers, each capable of generating 50 MW, 1.5 msec pulses, will be the main high power RF sources for the system. These klystrons will be powered by state of the art solid-state high voltage modulators. A RF pulse compressor, similar to the SLED II pulse compressor, will compress the klystron output pulse with a power gain factor of five. For compactness consideration, we are looking at a folded waveguide setup. This will give us 500 MW at output of the compressor. The compressed pulse will then be distributed to the RF gun and to six traveling wave accelerator sections. Phase and amplitude control are located at the RF gun input and additional control points along the LINAC to allow for parameter control during operation. This high power RF system is being designed and constructed. In this paper, we will present the design, layout, and status of this RF system.

  17. 500 MW X-BAND RF SYSTEM OF A 0.25 GEV ELECTRON LINAC FOR ADVANCED COMPTON SCATTERING SOURCE APPLICATION

    SciTech Connect

    Chu, T S; Anderson, S G; Gibson, D J; Hartemann, F V; Marsh, R A; Siders, C; Barty, C P; Adolphsen, C; Jongewaard, E; Tantawi, S; Vlieks, A; Wang, J W; Raubenheimer, T

    2010-05-12

    A Mono-Energetic Gamma-Ray (MEGa-Ray) Compton scattering light source is being developed at LLNL in collaboration with SLAC National Accelerator Laboratory. The electron beam for the Compton scattering interaction will be generated by a X-band RF gun and a X-band LINAC at the frequency of 11.424 GHz. High power RF in excess of 500 MW is needed to accelerate the electrons to energy of 250 MeV or greater for the interaction. Two high power klystron amplifiers, each capable of generating 50 MW, 1.5 msec pulses, will be the main high power RF sources for the system. These klystrons will be powered by state of the art solid-state high voltage modulators. A RF pulse compressor, similar to the SLED II pulse compressor, will compress the klystron output pulse with a power gain factor of five. For compactness consideration, we are looking at a folded waveguide setup. This will give us 500 MW at output of the compressor. The compressed pulse will then be distributed to the RF gun and to six traveling wave accelerator sections. Phase and amplitude control are located at the RF gun input and additional control points along the LINAC to allow for parameter control during operation. This high power RF system is being designed and constructed. In this paper, we will present the design, layout, and status of this RF system.

  18. Development and Validation of an Older Occupant Finite Element Model of a Mid-Sized Male for Investigation of Age-related Injury Risk.

    PubMed

    Schoell, Samantha L; Weaver, Ashley A; Urban, Jillian E; Jones, Derek A; Stitzel, Joel D; Hwang, Eunjoo; Reed, Matthew P; Rupp, Jonathan D; Hu, Jingwen

    2015-11-01

    The aging population is a growing concern as the increased fragility and frailty of the elderly results in an elevated incidence of injury as well as an increased risk of mortality and morbidity. To assess elderly injury risk, age-specific computational models can be developed to directly calculate biomechanical metrics for injury. The first objective was to develop an older occupant Global Human Body Models Consortium (GHBMC) average male model (M50) representative of a 65 year old (YO) and to perform regional validation tests to investigate predicted fractures and injury severity with age. Development of the GHBMC M50 65 YO model involved implementing geometric, cortical thickness, and material property changes with age. Regional validation tests included a chest impact, a lateral impact, a shoulder impact, a thoracoabdominal impact, an abdominal bar impact, a pelvic impact, and a lateral sled test. The second objective was to investigate age-related injury risks by performing a frontal US NCAP simulation test with the GHBMC M50 65 YO and the GHBMC M50 v4.2 models. Simulation results were compared to the GHBMC M50 v4.2 to evaluate the effect of age on occupant response and risk for head injury, neck injury, thoracic injury, and lower extremity injury. Overall, the GHBMC M50 65 YO model predicted higher probabilities of AIS 3+ injury for the head and thorax. PMID:26660751

  19. Reliability-Based Weighting of Visual and Vestibular Cues in Displacement Estimation

    PubMed Central

    ter Horst, Arjan C.; Koppen, Mathieu; Selen, Luc P. J.; Medendorp, W. Pieter

    2015-01-01

    When navigating through the environment, our brain needs to infer how far we move and in which direction we are heading. In this estimation process, the brain may rely on multiple sensory modalities, including the visual and vestibular systems. Previous research has mainly focused on heading estimation, showing that sensory cues are combined by weighting them in proportion to their reliability, consistent with statistically optimal integration. But while heading estimation could improve with the ongoing motion, due to the constant flow of information, the estimate of how far we move requires the integration of sensory information across the whole displacement. In this study, we investigate whether the brain optimally combines visual and vestibular information during a displacement estimation task, even if their reliability varies from trial to trial. Participants were seated on a linear sled, immersed in a stereoscopic virtual reality environment. They were subjected to a passive linear motion involving visual and vestibular cues with different levels of visual coherence to change relative cue reliability and with cue discrepancies to test relative cue weighting. Participants performed a two-interval two-alternative forced-choice task, indicating which of two sequentially perceived displacements was larger. Our results show that humans adapt their weighting of visual and vestibular information from trial to trial in proportion to their reliability. These results provide evidence that humans optimally integrate visual and vestibular information in order to estimate their body displacement. PMID:26658990

  20. Microhabitat and shrimp abundance within a Norwegian cold-water coral ecosystem

    NASA Astrophysics Data System (ADS)

    Purser, A.; Ontrup, J.; Schoening, T.; Thomsen, L.; Tong, R.; Unnithan, V.; Nattkemper, T. W.

    2013-09-01

    Cold-water coral (CWC) reefs are heterogeneous ecosystems comprising numerous microhabitats. A typical European CWC reef provides various biogenic microhabitats (within, on and surrounding colonies of coral species such as Lophelia pertusa, Paragorgia arborea and Primnoa resedaeformis, or formed by their remains after death). These microhabitats may be surrounded and intermixed with non-biogenic microhabitats (soft sediment, hard ground, gravel/pebbles, steep walls). To date, studies of distribution of sessile fauna across CWC reefs have been more numerous than those investigating mobile fauna distribution. In this study we quantified shrimp densities associated with key CWC microhabitat categories at the Røst Reef, Norway, by analysing image data collected by towed video sled in June 2007. We also investigated shrimp distribution patterns on the local scale (<40 cm) and how these may vary with microhabitat. Shrimp abundances at the Røst Reef were on average an order of magnitude greater in biogenic reef microhabitats than in non-biogenic microhabitats. Greatest shrimp densities were observed in association with live Paragorgia arborea microhabitat (43 shrimp m-2, SD = 35.5), live Primnoa resedaeformis microhabitat (41.6 shrimp m-2, SD = 26.1) and live Lophelia pertusa microhabitat (24.4 shrimp m-2, SD = 18.6). In non-biogenic microhabitat, shrimp densities were <2 shrimp m-2. CWC reef microhabitats appear to support greater shrimp densities than the surrounding non-biogenic microhabitats at the Røst Reef, at least at the time of survey.

  1. Microhabitat and shrimp abundance within a Norwegian cold-water coral ecosystem

    NASA Astrophysics Data System (ADS)

    Purser, A.; Ontrup, J.; Schoening, T.; Thomsen, L.; Tong, R.; Unnithan, V.; Nattkemper, T. W.

    2013-02-01

    Cold-water coral reefs are highly heterogeneous ecosystems comprising of a range of diverse microhabitats. In a typical European cold-water coral reef various biogenic habitats (live colonies of locally common coral species such as Lophelia pertusa, Paragorgia arborea and Primnoa resedaeformis, dead coral structure, coral rubble) may be surrounded and intermixed with non-biogenic habitats (soft sediment, hardground, gravel/pebbles, steep walls). To date, studies of distribution of sessile fauna across these microhabitats have been more numerous than those investigating mobile fauna distribution. In this study we quantified shrimp densities associated with key CWC habitat categories at the Røst reef, Norway, by analysing image data collected by towed video sled. We also investigated shrimp distribution patterns on the local scale (<40 cm) and how these may vary with habitat. We found shrimp abundances at the Røst reef to be on average an order of magnitude greater in biogenic reef habitats than in non-biogenic habitats. Greatest shrimp densities were observed in association with live Paragorgia arborea habitats (43 shrimp m-2, SD = 35.5), live Primnoa resedaeformis habitats (41.6 shrimp m-2, SD = 26.1) and live Lophelia pertusa habitats (24.4 shrimp m-2, SD = 18.6). In non-biogenic habitats shrimp densities were <2 shrimp m-2. We conclude that CWC reef habitats clearly support greater shrimp densities than the surrounding non-biogenic habitats on the Norwegian margin.

  2. Streamlined Approach for Environmental Restoration Plan for Corrective Action Unit 425: Area 9 Main Lake Construction Debris Disposal Area, Tonopah Test Range, Nevada

    SciTech Connect

    K. B. Campbell

    2002-04-01

    This Streamlined Approach for Environmental Restoration (SAFER) Plan addresses the action necessary for the closure of Corrective Action Unit (CAU) 425, Area 9 Main Lake Construction Debris Disposal Area. This CAU is currently listed in Appendix III of the Federal Facility Agreement and Consent Order (FFACO, 1996). This site will be cleaned up under the SAFER process since the volume of waste exceeds the 23 cubic meters (m{sup 3}) (30 cubic yards [yd{sup 3}]) limit established for housekeeping sites. CAU 425 is located on the Tonopah Test Range (TTR) and consists of one Corrective Action Site (CAS) 09-08-001-TA09, Construction Debris Disposal Area (Figure 1). CAS 09-08-001-TA09 is an area that was used to collect debris from various projects in and around Area 9. The site is located approximately 81 meters (m) (265 feet [ft]) north of Edwards Freeway northeast of Main Lake on the TTR. The site is composed of concrete slabs with metal infrastructure, metal rebar, wooden telephone poles, and concrete rubble from the Hard Target and early Tornado Rocket sled tests. Other items such as wood scraps, plastic pipes, soil, and miscellaneous nonhazardous items have also been identified in the debris pile. It is estimated that this site contains approximately 2280 m{sup 3} (3000 yd{sup 3}) of construction-related debris.

  3. a Study on the Mechanism of OCCUPANT'S Cervical Injury by Low Speed Rear-End Collision of Automobiles

    NASA Astrophysics Data System (ADS)

    Cho, Wonhak; Kim, Yongchul; Choi, Hyeonki

    Neck injury in rear-end car collisions is an increasing concern in the field of traffic safety. This injury commonly occurs at rear-end impact, however the injury mechanisms for whiplash remain a mystery. The purpose of this study is to quantitatively analyze the head and neck kinematics during the low-speed rear-end impact of automobiles. It is important to produce data that is related as closely as possible to the in vivo situation. So, we performed a sled test which simulated rear-end impacts with a velocity of 0.6 m/s with five normal healthy male subjects. 3-D motion analysis system was used to document motion data of two situations. When we compare the values of angular velocity and acceleration of head and neck, the peak magnitudes of inclined seated posture were smaller than those of upright seated posture. The result of this study is expected to provide insight that will aid in determining the mechanism of whiplash which is crucial to the identification of possible injury mechanisms.

  4. A constitutive model for layered wire mesh and aramid cloth fabric

    SciTech Connect

    Neilsen, M.K.; Pierce, J.D.; Krieg, R.D.

    1993-09-01

    A new package for the air transport of hazardous materials is currently being developed in the Transportation Systems Department at Sandia National Laboratories. The baseline design has a unique impact limiter which uses layers of aluminum screen wire and aramid cloth fabric. A primary motivation for selecting this unusual combination of materials is the need for the impact limiter to not only limit the amount of load transmitted to the primary container but also remain in place during impact events so that it provides a thermal barrier during a subsequent fire. A series of uniaxial and confined compression tests indicated that the layered material does not behave like other well characterized materials. No existing constitutive models were able to satisfactorily capture the behavior of the layered material; thus, a new plasticity model was developed. The new material model was then used to characterize the response of air transport packages with layered impact limiters to hypothetical accidental impact events. Responses predicted by these analyses compared favorably with experiments at Sandia`s rocket sled test facility in which a one-fourth scale package was subjected to side and end impacts at velocities of 428 and 650 fps, respectively.

  5. Conceptual Design and Analysis of Cold Mass Support of the CS3U Feeder for the ITER

    NASA Astrophysics Data System (ADS)

    Zhu, Yinfeng; Song, Yuntao; Zhang, Yuanbin; Wang, Zhongwei

    2013-06-01

    In the International Thermonuclear Experimental Reactor (ITER) project, the feeders are one of the most important and critical systems. To convey the power supply and the coolant for the central solenoid (CS) magnet, 6 sets of CS feeders are employed, which consist mainly of an in-cryostat feeder (ICF), a cryostat feed-through (CFT), an S-bend box (SBB), and a coil terminal box (CTB). To compensate the displacements of the internal components of the CS feeders during operation, sliding cold mass supports consisting of a sled plate, a cylindrical support, a thermal shield, and an external ring are developed. To check the strength of the developed cold mass supports of the CS3U feeder, electromagnetic analysis of the two superconducting busbars is performed by using the CATIA V5 and ANSYS codes based on parametric technology. Furthermore, the thermal-structural coupling analysis is performed based on the obtained results, except for the stress concentration, and the max. stress intensity is lower than the allowable stress of the selected material. It is found that the conceptual design of the cold mass support can satisfy the required functions under the worst case of normal working conditions. All these performed activities will provide a firm technical basis for the engineering design and development of cold mass supports.

  6. Crashworthiness of Aluminium Tubes; Part 2: Improvement of Hydroforming Operation to Increase Absorption Energy

    NASA Astrophysics Data System (ADS)

    D'Amours, Guillaume; Rahem, Ahmed; Mayer, Robert; Williams, Bruce; Worswick, Michael

    2007-05-01

    The motivation to reduce overall vehicle weight within the automotive sector drives the substitution of lightweight materials such as aluminium alloys for structural components. Such a substitution requires a significant amount of development to manufacture structurally parts such that the energy absorption characteristics are not sacrificed in the event of crash. The effects of the manufacturing processes on the crash performance of automotive structural components must be better understood to ensure improved crashworthiness. This paper presents results of an experimental and numerical investigation of the crash response and energy absorption properties of impacted hydroformed aluminium alloy tubes. Crash experiments on hydroformed tubes were performed using a deceleration sled test at the General Motors Technical Center. Results from axial crush testing showed that an important parameter that influences the energy absorption characteristics during crash was the thickness reduction caused by circumferential expansion of the tube during hydroforming. It was found that that the energy absorption decreased as the corner radius decreased, which results because of increased thinning. Sensitivity studies of end feeding parameters, such as end feed level and profile, were carried out to evaluate their impact on the energy absorption of the aluminium tubes.

  7. Simulation of car impact to pedestrian lower extremity: influence of different car-front shapes and dummy parameters on test results.

    PubMed

    Ishikawa, H; Kajzer, J; Ono, K; Sakurai, M

    1994-04-01

    Sled impact tests on mechanical substitutes for a pedestrian were conducted as a preliminary study for the purpose of developing a subsystem test procedure for the assessment of car-front aggressiveness to pedestrian legs. Four mechanical substitutes for a pedestrian were used in the test: the leg of a rotationally symmetrical pedestrian dummy (RSPD) as the representation of a subsystem, a HYBRID-II pedestrian dummy, a modified HYBRID-II pedestrian dummy equipped with a steel bar serving as knee joint, and a RSPD - HYBRID-IIP combined dummy in which the lower part of the RSPD and the upper part of the HYBRID-IIP were connected by a joint in such a way that the movements of the upper part were similar to those in cadaver tests. In the tests the following were evaluated: (i) the influence of vehicle shape on knee response and on vehicle impact force; (ii) the influence of the upper body mass on knee response and on vehicle impact forces; (iii) the influence of the bumper system on knee response, the kinematics of pedestrian mechanical substitute, and on vehicle impact forces; (iv) the influence of pedestrian mechanical substitute characteristics on its kinematics and knee response, and on vehicle impact forces. This paper describes a primary concept when subsystem test methods for the assessment of car-front aggressiveness to pedestrian legs in a car-pedestrian collision are considered. PMID:8198692

  8. Feasibility study on conducting overflight measurements of shaped sonic boom signatures using the Firebee BQM-34E RPV

    NASA Astrophysics Data System (ADS)

    Maglieri, Domenic J.; Sothcott, Victor E.; Keefer, Thomas N., Jr.

    1993-02-01

    A study was performed to determine the feasibility of establishing if a 'shaped' sonic boom signature, experimentally shown in wind tunnel models out to about 10 body lengths, will persist out to representative flight conditions of 200 to 300 body lengths. The study focuses on the use of a relatively large supersonic remotely-piloted and recoverable vehicle. Other simulation methods that may accomplish the objective are also addressed and include the use of nonrecoverable target drones, missiles, full-scale drones, very large wind tunnels, ballistic facilities, whirling-arm techniques, rocket sled tracks, and airplane nose probes. In addition, this report will also present a background on the origin of the feasibility study including a brief review of the equivalent body concept, a listing of the basic sonic boom signature characteristics and requirements, identification of candidate vehicles in terms of desirable features/availability, and vehicle characteristics including geometries, area distributions, and resulting sonic boom signatures. A program is developed that includes wind tunnel sonic boom and force models and tests for both a basic and modified vehicles and full-scale flight tests.

  9. Fracture of the lateral process of the talus: a report of two cases.

    PubMed

    Lunebourg, Alexandre; Zermatten, Philippe

    2014-01-01

    Fracture of the lateral process of the talus is a rare lesion commonly described in snowboarding injuries. Nevertheless, several conditions can lead to this injury, which is often misdiagnosed as a severe ankle sprain because of the difficulty in detecting it on standard radiographic views. Computed tomography is very helpful for the assessment of this injury. The type of treatment will depend on the size and degree of the displacement of the fracture. This injury can also lead to subtalar joint osteoarthritis. We report 2 cases of fracture of the lateral process of the talus. In the first case, a young male sustained a combined inversion and dorsiflexion strain of his right foot when he fell from a ladder. In the second case, a woman broke the lateral process of her right talus by the same mechanism when she was sledding. In the 2 situations, we opted for an open reduction and internal fixation using 2.4-mm cannulated screws. Both patients were allowed walking with partial weightbearing with a walker boot (VACOped(®)) for 6 weeks. At 1 year, both showed a consolidated fracture and had regained their preinjury level of activity. PMID:24618244

  10. Advanced instrument system for real-time and time-series microbial geochemical sampling of the deep (basaltic) crustal biosphere

    NASA Astrophysics Data System (ADS)

    Cowen, James P.; Copson, David A.; Jolly, James; Hsieh, Chih-Chiang; Lin, Huei-Ting; Glazer, Brian T.; Wheat, C. Geoffrey

    2012-03-01

    Integrated Ocean Drilling Program borehole CORK (Circulation Obviation Retrofit Kit) observatories provide long-term access to hydrothermal fluids circulating within the basaltic crust (basement), providing invaluable opportunities to study the deep biosphere. We describe the design and application parameters of the GeoMICROBE instrumented sled, an autonomous sensor and fluid sampling system. The GeoMICROBE system couples with CORK fluid delivery lines to draw large volumes of fluids from crustal aquifers to the seafloor. These fluids pass a series of in-line sensors and an in situ filtration and collection system. GeoMICROBE's major components include a primary valve manifold system, a positive displacement primary pump, sensors (e.g., fluid flow rate, temperature, dissolved O2, electrochemistry-voltammetry analyzer), a 48-port in situ filtration and fluid collection system, computerized controller, seven 24 V-40 A batteries and wet-mateable (ODI) communications with submersibles. This constantly evolving system has been successfully connected to IODP Hole 1301A on the eastern flank of the Juan de Fuca Ridge. Also described here is a mobile pumping system (MPS), which possesses many of the same components as the GeoMICROBE (e.g., pump, sensors, controller), but is directly powered and controlled in real time via submersible operations; the MPS has been employed repeatedly to collect pristine basement fluids for a variety of geochemical and microbial studies.

  11. Modeling spatial trajectories in dynamics testing using basis splines: application to tracking human volunteers in low-speed frontal impacts.

    PubMed

    Samuels, Marina A; Reed, Matthew P; Arbogast, Kristy B; Seacrist, Thomas

    2016-01-01

    Designing motor vehicle safety systems requires knowledge of whole body kinematics during dynamic loading for occupants of varying size and age, often obtained from sled tests with postmortem human subjects and human volunteers. Recently, we reported pediatric and adult responses in low-speed (<4 g) automotive-like impacts, noting reductions in maximum excursion with increasing age. Since the time-based trajectory shape is also relevant for restraint design, this study quantified the time-series trajectories using basis splines and developed a statistical model for predicting trajectories as a function of body dimension or age. Previously collected trajectories of the head, spine, and pelvis were modeled using cubic basis splines with eight control points. A principal component analysis was conducted on the control points and related to erect seated height using a linear regression model. The resulting statistical model quantified how trajectories became shorter and flatter with increasing body size, corresponding to the validation data-set. Trajectories were then predicted for erect seated heights corresponding to pediatric and adult anthropomorphic test devices (ATDs), thus generating performance criteria for the ATDs based on human response. This statistical model can be used to predict trajectories for a subject of specified anthropometry and utilized in subject-specific computational models of occupant response. PMID:26428257

  12. The Clock Is Ticking

    NASA Technical Reports Server (NTRS)

    Gundo, Dan

    2003-01-01

    Recently, I worked on creating a one-of-a-kind device for a Space Station group studying exercise physiology at another NASA Center. They approached my department at Ames Research Center to design and build an exercise bed that allowed users to perform the motions that they needed for ground-based research. The real challenge was that they needed the device designed, built, and delivered in just one month. The bed was intended to simulate doing squats while in a horizontal position as if on a moving sled. They wanted to incorporate a resistant device called an Interim Resistive Exercise Device (IRED), an adjustable cable tied into a reel to provide a measured amount of resistance. This device was used on the Station for exercising in space; we were taking the same resistant reel and incorporating it in this bed. In the early stages of a design project, I communicate with a customer as much as I can and as often as they will tolerate. There s a lot of learning that needs to go on, and I prefer to spend a little bit of extra time here because that can save a lot of time later. In the beginning, you need to volley the information back-and-forth, so that you understand the customer s requirements and they know what you re capable of doing.

  13. Reliability-Based Weighting of Visual and Vestibular Cues in Displacement Estimation.

    PubMed

    ter Horst, Arjan C; Koppen, Mathieu; Selen, Luc P J; Medendorp, W Pieter

    2015-01-01

    When navigating through the environment, our brain needs to infer how far we move and in which direction we are heading. In this estimation process, the brain may rely on multiple sensory modalities, including the visual and vestibular systems. Previous research has mainly focused on heading estimation, showing that sensory cues are combined by weighting them in proportion to their reliability, consistent with statistically optimal integration. But while heading estimation could improve with the ongoing motion, due to the constant flow of information, the estimate of how far we move requires the integration of sensory information across the whole displacement. In this study, we investigate whether the brain optimally combines visual and vestibular information during a displacement estimation task, even if their reliability varies from trial to trial. Participants were seated on a linear sled, immersed in a stereoscopic virtual reality environment. They were subjected to a passive linear motion involving visual and vestibular cues with different levels of visual coherence to change relative cue reliability and with cue discrepancies to test relative cue weighting. Participants performed a two-interval two-alternative forced-choice task, indicating which of two sequentially perceived displacements was larger. Our results show that humans adapt their weighting of visual and vestibular information from trial to trial in proportion to their reliability. These results provide evidence that humans optimally integrate visual and vestibular information in order to estimate their body displacement. PMID:26658990

  14. Context-specific adaptation of the gain of the oculomotor response to lateral translation using roll and pitch head tilts as contexts

    NASA Technical Reports Server (NTRS)

    Shelhamer, Mark; Peng, Grace C Y.; Ramat, Stefano; Patel, Vivek

    2002-01-01

    Previous studies established that vestibular and oculomotor behaviors can have two adapted states (e.g., gain) simultaneously, and that a context cue (e.g., vertical eye position) can switch between the two states. The present study examined this phenomenon of context-specific adaptation for the oculomotor response to interaural translation (which we term "linear vestibulo-ocular reflex" or LVOR even though it may have extravestibular components). Subjects sat upright on a linear sled and were translated at 0.7 Hz and 0.3 gpeak acceleration while a visual-vestibular mismatch paradigm was used to adaptively increase (x2) or decrease (x0) the gain of the LVOR. In each experimental session, gain increase was asked for in one context, and gain decrease in another context. Testing in darkness with steps and sines before and after adaptation, in each context, assessed the extent to which the context itself could recall the gain state that was imposed in that context during adaptation. Two different contexts were used: head pitch (26 degrees forward and backward) and head roll (26 degrees or 45 degrees, right and left). Head roll tilt worked well as a context cue: with the head rolled to the right the LVOR could be made to have a higher gain than with the head rolled to the left. Head pitch tilt was less effective as a context cue. This suggests that the more closely related a context cue is to the response being adapted, the more effective it is.

  15. Early observations on an emerging Great Lakes invader Hemimysis anomala in Lake Ontario

    USGS Publications Warehouse

    Walsh, Maureen G.; Lantry, Brian F.; Boscarino, Brent; Bowen, Kelly; Gerlofsma, Jocelyn; Schaner, Ted; Back, Richard; Questel, Jennifer; Smythe, A. Garry; Cap, Roberta; Goehle, Michael; Young, Bryan; Chalupnicki, Marc A.; Johnson, James H.; McKenna, James E.

    2010-01-01

    Hemimysis anomala, a Ponto-Caspian littoral mysid, is an emerging Great Lakes invader that was discovered in Lakes Michigan and Ontario in 2006. Similar to the native mysid Mysis diluviana, Hemimysis exhibits a diel vertical migration pattern but generally inhabits shallower and warmer waters than M. diluviana. Because basic information on the distribution, habitat use, and biology of Hemimysis in the Great Lakes is scarce, the potential for food web disruption by Hemimysis cannot easily be predicted. Preliminary observations indicate widespread invasion of Hemimysis in Lake Ontario. In this study, we confirm the presence of Hemimysis at sites spanning the northern and southern shores of Lake Ontario and the presence of the individuals during winter months. In one horizontal tow in November 2007, over 26,000 individuals were collected with a length range of 4.4 to 9.0. mm and an average caloric density of 611. cal/g wet weight. The most effective methods for sampling Hemimysis were horizontal tows with either a zooplankton net in the water column or a benthic sled near the lake bottom. Although more quantitative data on the life history and distribution of this species is necessary, our preliminary observations support the prediction that the potential for Hemimysis to impact the nearshore food web in Lake Ontario appears high.

  16. Passive flooding of paranasal sinuses and middle ears as a method of equalisation in extreme breath-hold diving.

    PubMed

    Germonpré, Peter; Balestra, Costantino; Musimu, Patrick

    2011-06-01

    Breath-hold diving is both a recreational activity, performed by thousands of enthusiasts in Europe, and a high-performance competitive sport. Several 'disciplines' exist, of which the 'no-limits' category is the most spectacular: using a specially designed heavy 'sled,' divers descend to extreme depths on a cable, and then reascend using an inflatable balloon, on a single breath. The current world record for un-assisted descent stands at more than 200 m of depth. Equalising air pressure in the paranasal sinuses and middle-ear cavities is a necessity during descent to avoid barotraumas. However, this requires active insufflations of precious air, which is thus unavailable in the pulmonary system. The authors describe a diver who, by training, is capable of allowing passive flooding of the sinuses and middle ear with (sea) water during descent, by suppressing protective (parasympathetic) reflexes during this process. Using this technique, he performed a series of extreme-depth breath-hold dives in June 2005, descending to 209 m of sea water on one breath of air. PMID:20961916

  17. Splenic Trauma as an Adverse Effect of Torso-Protecting Side Airbags: Biomechanical and Case Evidence

    PubMed Central

    Hallman, Jason J.; Brasel, Karen J.; Yoganandan, Narayan; Pintar, Frank A.

    2009-01-01

    Injury mechanisms from frontal airbags, first identified in anecdotal reports, are now well documented for pediatric, small female, and out-of-position occupants. In contrast, torso side airbags have not yet been consistently associated with specific injury risks in field assessments. To determine possible torso side airbag-related injuries, the present study identified crashes involving side airbags from reports within the CIREN, NASS, and SCI databases. Injury patterns were compared to patterns from lateral crashes in absence of side airbag. Splenic trauma (AIS 3+) was found present in five cases of torso side airbag deployment at lower impact severity (as measured by velocity change and compartment intrusion) than cases of splenic trauma without side airbag. Five additional cases were found to contain similar injury patterns but occurred with greater crash severity. To supplement case analyses, full scale sled tests were conducted with a THOR-NT dummy and cadaveric specimen. Four THOR tests with door- and seat-mounted torso side airbags confirmed that out-of-position (early inflation stage) airbag contact elevated thoracic injury metrics compared to optimal (fully inflated) contact. Out-of-position seat-mounted airbag deployment also produced AIS 3 splenic trauma in the cadaveric specimen. Due to potentially sudden or delayed onset of intraperitoneal hemorrhage and hypovolemic shock following splenic trauma, further biomechanical investigation of this anecdotal evidence is essential to identify injury mechanisms, prevention techniques, and methods for early diagnosis. PMID:20184829

  18. Acoustic Doppler velocity measurement system using capacitive micromachined ultrasound transducer array technology.

    PubMed

    Shin, Minchul; Krause, Joshua S; DeBitetto, Paul; White, Robert D

    2013-08-01

    This paper describes the design, fabrication, modeling, and characterization of a small (1 cm(2) transducer chip) acoustic Doppler velocity measurement system using microelectromechanical systems capacitive micromachined ultrasound transducer (cMUT) array technology. The cMUT sensor has a 185 kHz resonant frequency to achieve a 13° beam width for a 1 cm aperture. A model for the cMUT and the acoustic system which includes electrical, mechanical, and acoustic components is provided. Furthermore, this paper shows characterization of the cMUT sensor with a variety of testing procedures including Laser Doppler Vibrometry (LDV), beampattern measurement, reflection testing, and velocity testing. LDV measurements demonstrate that the membrane displacement at the center point is 0.4 nm/V(2) at 185 kHz. The maximum range of the sensor is 60 cm (30 cm out and 30 cm back). A velocity sled was constructed and used to demonstrate measureable Doppler shifts at velocities from 0.2 to 1.0 m/s. The Doppler shifts agree well with the expected frequency shifts over this range. PMID:23927100

  19. Closure Report for Corrective Action Unit 425: Area 9 Main Lake Construction Debris Disposal Area, Tonopah Test Range, Nevada

    SciTech Connect

    K. B. Campbell

    2003-03-01

    Corrective Action Unit (CAU) 425 is located on the Tonopah Test Range, approximately 386 kilometers (240 miles) northwest of Las Vegas, Nevada. CAU 425 is listed in the Federal Facility Agreement and Consent Order (FFACO, 1996) and is comprised of one Corrective Action Site (CAS). CAS 09-08-001-TA09 consisted of a large pile of concrete rubble from the original Hard Target and construction debris associated with the Tornado Rocket Sled Tests. CAU 425 was closed in accordance with the FFACO and the Nevada Division of Environmental Protection-approved Streamlined Approach for Environmental Restoration Plan for CAU 425: Area 9 Main Lake Construction Debris Disposal Area, Tonopah Test Range, Nevada (U.S. Department of Energy, Nevada Operations Office, 2002). CAU 425 was closed by implementing the following corrective actions: The approved corrective action for this unit was clean closure. Closure activities included: (1) Removal of all the debris from the site. (2) Weighing each load of debris leaving the job site. (3) Transporting the debris to the U.S. Air Force Construction Landfill for disposal. (4) Placing the radioactive material in a U.S. Department of Transportation approved container for proper transport and disposal. (5) Transporting the radioactive material to the Nevada Test Site for disposal. (6) Regrading the job site to its approximate original contours/elevation.

  20. Ambiguous Tilt and Translation Motion Cues in Astronauts after Space Flight

    NASA Technical Reports Server (NTRS)

    Clement, G.; Harm, D. L.; Rupert, A. H.; Beaton, K. H.; Wood, S. J.

    2008-01-01

    Adaptive changes during space flight in how the brain integrates vestibular cues with visual, proprioceptive, and somatosensory information can lead to impaired movement coordination, vertigo, spatial disorientation, and perceptual illusions following transitions between gravity levels. This joint ESA-NASA pre- and post-flight experiment is designed to examine both the physiological basis and operational implications for disorientation and tilt-translation disturbances in astronauts following short-duration space flights. The first specific aim is to examine the effects of stimulus frequency on adaptive changes in eye movements and motion perception during independent tilt and translation motion profiles. Roll motion is provided by a variable radius centrifuge. Pitch motion is provided by NASA's Tilt-Translation Sled in which the resultant gravitoinertial vector remains aligned with the body longitudinal axis during tilt motion (referred to as the Z-axis gravitoinertial or ZAG paradigm). We hypothesize that the adaptation of otolith-mediated responses to these stimuli will have specific frequency characteristics, being greatest in the mid-frequency range where there is a crossover of tilt and translation. The second specific aim is to employ a closed-loop nulling task in which subjects are tasked to use a joystick to null-out tilt motion disturbances on these two devices. The stimuli consist of random steps or sum-of-sinusoids stimuli, including the ZAG profiles on the Tilt-Translation Sled. We hypothesize that the ability to control tilt orientation will be compromised following space flight, with increased control errors corresponding to changes in self-motion perception. The third specific aim is to evaluate how sensory substitution aids can be used to improve manual control performance. During the closed-loop nulling task on both devices, small tactors placed around the torso vibrate according to the actual body tilt angle relative to gravity. We hypothesize

  1. Feasibility Study of a Lunar Analog Bed Rest Model

    NASA Technical Reports Server (NTRS)

    Cromwell, Ronita L.; Platts, Steven H.; Yarbough, Patrice; Buccello-Stout, Regina

    2010-01-01

    The purpose of this study was to determine the feasibility of using a 9.5deg head-up tilt bed rest model to simulate the effects of the 1/6 g load to the human body that exists on the lunar surface. The lunar analog bed rest model utilized a modified hospital bed. The modifications included mounting the mattress on a sled that rolled on bearings to provide freedom of movement. The weight of the sled was off-loaded using a counterweight system to insure that 1/6 body weight was applied along the long axis (z-axis) of the body. Force was verified through use of a force plate mounted at the foot of the bed. A seating assembly was added to the bed to permit periods of sitting. Subjects alternated between standing and sitting positions throughout the day. A total of 35% of the day was spent in the standing position and 65% was spent sitting. In an effort to achieve physiologic fluid shifts expected for a 1/6 G environment, subjects wore compression stockings and performed unloaded foot and ankle exercises. Eight subjects (3 females and 5 males) participated in this study. Subjects spent 13 days in the pre-bed rest phase, 6 days in bed rest and 3 days post bed rest. Subjects consumed a standardized diet throughout the study. To determine feasibility, measures of subject comfort, force and plasma volume were collected. Subject comfort was assessed using a Likert scale. Subjects were asked to assess level of comfort (0-100) for 11 body regions and provide an overall rating. Results indicated minimal to no discomfort as most subjects reported scores of zero. Force measures were performed for each standing position and were validated against subject s calculated 1/6 body weight (r(sup 2) = 0.993). The carbon monoxide rebreathing technique was used to assess plasma volume during pre-bed rest and on the last day of bed rest. Plasma volume results indicated a significant decrease (p = 0.001) from pre to post bed rest values. Subjects lost on average 8.3% (sd = 6.1%) during the

  2. A Fine-Resolution Radar for Mapping Near-Surface Isochronous Layers

    NASA Astrophysics Data System (ADS)

    Rink, T. P.; Kanagaratnam, P.; Braaten, D.; Zimmerman, K.; Akins, T.; Gogineni, S.

    2005-12-01

    Information on the spatial and temporal variation of snow accumulation is required for interpreting satellite-based radar and laser surface elevation measurements made by CryoSAT and ICESAT altimeters. Current methods of using ice cores and analyzing snow pit stratigraphy is time consuming and prone to errors in spatial representation due to the sparse sampling. Remote sensing methods that can map near-surface internal layers for estimating spatial and temporal variation are required. To accomplish this, we developed a 12-18 GHz FMCW radar to map near-surface layers with 3 cm vertical resolution to a depth of about 10 m. We developed the system to be mobile and self-contained so that spatial variability of the accumulation over a large area can be characterized. The fine resolution of this radar is achieved by its wide bandwidth and by illuminating the target area with a plane-wave, which is implemented using an offset-fed parabolic reflector. Traditional wide-beamwidth antennas are susceptible to spherical wave scattering from off-vertical targets that can potentially mask weaker reflections from internal layers. The radar features a fast transmit waveform synthesizer implemented using a voltage controlled oscillator (VCO) and a phase-locked loop (PLL) using a linear chirp as the reference. The highly linear reference chirp was generated by a direct digital synthesis (DDS) waveform generator and compared against the instantaneous output of the VCO to create a highly linear 12 to 18 GHz transmit chirp. The waveform synthesizer can be swept from 12 to 18 GHz in 500 microseconds. The antenna was mounted on a sled and the radar system was integrated with the antenna feed. We designed and built the sled with a gimbaled antenna mount and sensing control system to ensure that the antenna points at nadir. The radar system was successfully tested at the Summit camp, Greenland, in July 2005. We collected a large amount of data from various locations around Summit camp. The

  3. Type-II InAs/GaSb superlattice LEDs: Applications for infrared scene projector systems

    NASA Astrophysics Data System (ADS)

    Norton, Dennis Thomas, Jr.

    multiple active regions, coupled by tunnel junctions. Tunnel junctions must provide adequate barriers to prevent carrier leakage, while at the same time remain low in tunneling resistance to prevent unwanted heating. The performance of two tunnel junction designs are compared in otherwise identical four stage InAs/GaSb superlattice LED (SLED) devices for application in IRSP systems. This research culminated in the development of a 48 mum pitch, 512 x 512 individually addressable mid-wave IR LED array based on a sixteen stage, InAs/GaSb T2SL device design. This array was hybridized to a read-in integrated circuit and exhibited a pixel yield greater than 95 %. Projections based on single element emitter results predict this array will be able to achieve a peak apparent temperature of 1350 K within the entire 3-5 mum band. These results demonstrate the feasibility of emitter arrays intended for IRSP systems based on InAs/GaSb SLED devices. Additionally, a dual wavelength 48 mum pitch, 8 x 8 emitter array based on InAs/GaSb T2SL LEDs was developed and demonstrated. This design incorporates two separate, 16 stage InAs/GaSb SL active regions with varying InAs layer thicknesses built into a single vertical heterostructure. The device architecture is a three terminal device allowing for independent control of the intensity of each emission region. Each emitter region creates a contiguous pixel, capable of being planarized and mated to drive electronics.

  4. Archive of side scan sonar and swath bathymetry data collected during USGS cruise 10CCT01 offshore of Cat Island, Gulf Islands National Seashore, Mississippi, March 2010

    USGS Publications Warehouse

    DeWitt, Nancy T.; Flocks, James G.; Pfeiffer, William R.; Wiese, Dana S.

    2010-01-01

    activity for that project in that calendar year. Refer to http://walrus.wr.usgs.gov/infobank/programs/html/definition/activity.html for a detailed description of the method used to assign the field activity ID. Data were collected using a 26-foot (ft) Glacier Bay Catamaran. Side scan sonar and interferometric swath bathymetry data were collected simultaneously along the tracklines. The side scan sonar towfish was towed off the port side just slightly behind the vessel, close to the seafloor. The interferometric swath transducer was sled-mounted on a rail attached between the catamaran hulls. During the survey the sled is secured into position. Navigation was acquired with a CodaOctopus Octopus F190 Precision Attitude and Positioning System and differentially corrected with OmniSTAR. See the digital FACS equipment log for details about the acquisition equipment used. Both raw datasets were stored digitally and processed using CARIS HIPS and SIPS software at the USGS St. Petersburg Coastal and Marine Science Center. For more information on processing refer to the Equipment and Processing page. Post-processing of the swath dataset revealed a motion artifact that is attributed to movement of the pole that the swath transducers are attached to in relation to the boat. The survey took place in the winter months, in which strong winds and rough waves contributed to a reduction in data quality. The rough seas contributed to both the movement of the pole and the very high noise base seen in the raw amplitude data of the side scan sonar. Chirp data were also collected during this survey and are archived separately.

  5. Analysis of spinal motion and loads during frontal impacts. Comparison between PMHS and ATD.

    PubMed

    Lopez-Valdes, Francisco J; Lau, Anthony; Lamp, John; Riley, Patrick; Lessley, David J; Damon, Andrew; Kindig, Matthew; Kent, Richard; Balasubramanian, Sriram; Seacrist, Thomas; Maltese, Matthew R; Arbogast, Kristy B; Higuchi, Kazuo; Tanji, Hiro

    2010-01-01

    Quantifying the kinematics of the human spine during a frontal impact is a challenge due to the multi-degree-of-freedom structure of the vertebral column. This papers reports on a series of six frontal impacts sled tests performed on three Post Mortem Human Surrogates (PMHS). Each subject was exposed first to a low-speed, non-injurious frontal impact (9 km/h) and then to a high-speed one (40 km/h). Five additional tests were performed using the Hybrid III 50(th) percentile male ATD for comparison with the PMHS. A 3D motion capture system was used to record the 6-degree-of-freedom motion of body segments (head, T1, T8, L2, L4 and pelvis). The 3D trajectories of individual bony structures in the PMHS were determined using bone-mounted marker arrays, thus avoiding skin-attached markers and their potential measurements artifacts. The PMHS spines showed different behavior between low and high speed. While at low speed the head and upper spinal segments lagged the lower portion of the spine and pelvis in reaching their maximum forward displacement (time for maximum forward head excursion was 254.3±31.9 ms and 140.3±9 ms for the pelvis), these differences were minimal at high speed (127±2.6 ms for the head vs. 116.7±3.5 ms for the pelvis). The ATD did not exhibit this speed-dependant behavior. Furthermore, the ATD's forward displacements were consistently less than those exhibited by the PMHS, regardless of the speed. Neck loads at the atlanto-occipital joint were estimated for the PMHS using inverse dynamics techniques and compared to those measured in the ATD. It was found that the axial and shear forces and the flexion moment at the upper neck of the PMHS were higher than those measured in the ATD. PMID:21050592

  6. Flatfish-habitat associations in Alaska nursery grounds: Use of continuous video records for multi-scale spatial analysis

    NASA Astrophysics Data System (ADS)

    Stoner, Allan W.; Spencer, Mara L.; Ryer, Clifford H.

    2007-02-01

    Flatfish distributions have traditionally been described in terms of depth, temperature, and sediment characteristics, but other environmental variables may be important depending upon spatial scale. Surveys for age-0 northern rock sole ( Lepidopsetta polyxystra) were conducted in five near-shore nursery sites at Kodiak Island, Alaska, using a towed camera sled integrated with navigational data. The continuous record of fish density and habitat features made possible a spatially comprehensive analysis of fish-habitat associations at several spatial scales, ranging from tens of kilometres to less than 1 m. A combination of multivariate statistical interpretation and geographic information systems (GIS) revealed that the distribution of juvenile rock sole was associated with environmental variables and spatial scales that are not normally detectable with usual flatfish— and habitat—sampling methods (i.e., trawls and grabs). Generalized additive models (GAM) incorporating habitat variables determined from video provided large improvements over models using only the traditional variables such as depth and sediment type. At the broadest (regional) scale of analysis, combinations of sediment composition, surface bedform, temperature, and density of worm tubes provided the best model for rock sole density. Within-nursery variation in fish density was modelled best with depth, habitat structural complexity created by emergent fauna and macroalgae, and worm tube density. At the microhabitat scale (< 1 m), there was little evidence of direct contact between rock sole and structures such as shell or algae. Rather, they were loosely associated on a scale tens of metres. This study showed that spatially comprehensive surveys can be conducted with towed camera systems and without the need for sediment grab samples. This approach yields detailed habitat information for fishes and the opportunity for landscape analysis of spatial patterns that will be important in conserving

  7. Analysis of the stability of PTW riders in autonomous braking scenarios.

    PubMed

    Symeonidis, Ioannis; Kavadarli, Gueven; Erich, Schuller; Graw, Matthias; Peldschus, Steffen

    2012-11-01

    While fatalities of car occupants in the EU decreased remarkably over the last decade, Powered Two Wheelers (PTWs) fatalities still increase following the increase of PTW ownership. Autonomous braking systems have been implemented in several types of vehicles and are presently addressed by research in the field of PTWs. A major concern in this context is the rider stability. Experiments with volunteers were performed in order to find out whether autonomous braking for PTWs will produce a greater instability of the rider in comparison to manual braking. The PTW's braking conditions were simulated in a laboratory with a motorcycle mock-up mounted on a sled, which was accelerated with an average of 0.35 g. The motion of the rider was captured in autonomous braking scenarios with and without pre-warning as well as in manual braking scenarios. No significant differences between the scenarios were found with respect to maximum forward displacement of the volunteer's torso and head (p<0.05). By performing clustering analysis on two kinematic parameters, two different strategies of the volunteers were identified. They were not related to the braking scenarios. A relation of the clusters with the initial posture represented by the elbow angle was revealed (p<0.05). It is concluded that autonomous braking at low deceleration will not cause significant instabilities of the rider in comparison to manual braking in idealized laboratory conditions. Based on this, further research into the development and implementation of autonomous braking systems for PTWs, e.g. by extensive riding tests, seems valuable. PMID:23036398

  8. Bryozoan faunal composition and community structure from the continental shelf off Cap de Creus (Northwestern Mediterranean)

    NASA Astrophysics Data System (ADS)

    Madurell, T.; Zabala, M.; Dominguez-Carrió, C.; Gili, J. M.

    2013-10-01

    Bryozoan specimens obtained in 2009-2010 from the continental shelf off Cap de Creus (Northwestern Mediterranean) were studied. Samples were collected using a Rauschert sled at depths ranging from 61 to 225 m. Bryozoans were present in all 26 samples examined, although they were only abundant in 20 of them. A total of 113 species of Bryozoa were identified (2 Ctenostomata, 90 Cheilostomata and 21 Cyclostomata), most of them are well known to science, although a few of the species have barely or never been cited in the Mediterranean Sea (Hincksinoflustra octodon, Alderina imbellis, Escharella immersa, Neolagenipora collaris and Escharina johnstoni), or are currently poorly described (Lagenipora lepralioides). The species Palmicellaria aff. aviculifera (sensu Gautier, 1957) is redescribed, for which the new name of Palmiskenea gautieri is proposed. Species richness, abundance and biomass were linked to the availability of suitable substrates. Multivariate analysis in relation to environmental data showed that the spatial distribution of the bryozoan species was related to the sediment type. Samples from areas dominated by silt and sandy sediments showed few or no bryozoans, whereas coarse sands and gravels presented higher diversity, abundance and biomass. Within the depth range studied, the faunistic composition of the bryozoan assemblages was similar for the whole continental shelf off Cap de Creus. The bulk of bryozoans was found near the canyon rim. This is related to the proximity of the submarine canyon and its associated hydrological processes. The high diversity and abundance of the bryozoan community located on the circalittoral and shelf-edge off Cap de Creus reflect the presence of critical habitats that are essential for the design of marine protected areas.

  9. Improvement of brain segmentation accuracy by optimizing non-uniformity correction using N3.

    PubMed

    Zheng, Weili; Chee, Michael W L; Zagorodnov, Vitali

    2009-10-15

    Smoothly varying and multiplicative intensity variations within MR images that are artifactual, can reduce the accuracy of automated brain segmentation. Fortunately, these can be corrected. Among existing correction approaches, the nonparametric non-uniformity intensity normalization method N3 (Sled, J.G., Zijdenbos, A.P., Evans, A.C., 1998. Nonparametric method for automatic correction of intensity nonuniformity in MRI data. IEEE Trans. Med. Imag. 17, 87-97.) is one of the most frequently used. However, at least one recent study (Boyes, R.G., Gunter, J.L., Frost, C., Janke, A.L., Yeatman, T., Hill, D.L.G., Bernstein, M.A., Thompson, P.M., Weiner, M.W., Schuff, N., Alexander, G.E., Killiany, R.J., DeCarli, C., Jack, C.R., Fox, N.C., 2008. Intensity non-uniformity correction using N3 on 3-T scanners with multichannel phased array coils. NeuroImage 39, 1752-1762.) suggests that its performance on 3 T scanners with multichannel phased-array receiver coils can be improved by optimizing a parameter that controls the smoothness of the estimated bias field. The present study not only confirms this finding, but additionally demonstrates the benefit of reducing the relevant parameter values to 30-50 mm (default value is 200 mm), on white matter surface estimation as well as the measurement of cortical and subcortical structures using FreeSurfer (Martinos Imaging Centre, Boston, MA). This finding can help enhance precision in studies where estimation of cerebral cortex thickness is critical for making inferences. PMID:19559796

  10. Finding of a huge coral reef sliding down to the bottom of the Palau Trench

    NASA Astrophysics Data System (ADS)

    Fujioka, K.; Kitazato, H.; Wada, H.

    2006-12-01

    We found a huge limestone block from the Palau Trench bottom, southern Philippine Sea by submersible Shinkai 6500. The limestone consists of the shallow marine coral reef similar with that of the present coral reefs of the Palau Islands. The site of a huge limestone body is located at the southern part of the Palau Trench at the water depth of 6400 m. The size of coral reef is confirmed to be of 2km x 2 km x 1 km by submersible observation but bathymetric survey confirm the distribution of the coral reef to be of 20 km x 10 km x 3 km. The limestone of the coral reef shows striations by the fall down blocks. The surface of the limestone is dissolved nature because of the depth being deeper than that of the Carbonate Compensation Depth (CCD), ca. 4200 m in the western Pacific. The limestone body is intercalated by a black sediment and is covered by both calcareous planktonic and benthic foraminifers which indicate the very shallow marine environment. Age of the limestone is middle Miocene by the Sr isotope age determination as well as fossils in the limestone itself. The bathymetric survey revealed a huge horseshoe morphology now forming a submarine canyon structure nearby the limestone site. Gravity and magnetic survey show the notable anomaly for several seamounts on the Caroline Plate. We had a scenario that the coral reef was once exposed on land along the Palau arc then collapsed and sledded down to the trench bottom by the tectonic erosion of the forearc of the Palau Trench due to the subduction of seamounts on the Caroline Plate at sometime during Pleistocene. In the Palauan people have legends of their history making storyboards which tell us a story that the Palau Island was sinking.

  11. Effects of Short- and Long-Duration Space Flight on Neuromuscular Function

    NASA Technical Reports Server (NTRS)

    Buxton, Roxanne E.; Spiering, Barry A.; Ryder, Jeffrey W.; Ploutz-Snyder, Lori L.; Bloomberg, Jacob J.

    2010-01-01

    The Functional Task Tests (FTT) is an interdisciplinary study designed to correlate the changes in functional tasks (such as emergency egress, ladder climbing, and hatch opening) with changes in neuromuscular, cardiovascular, and sensorimotor function. One aspect of the FTT, the neuromuscular function test, is used to investigate the neuromuscular component underlying changes in the ability of astronauts to perform functional tasks (representative of critical mission tasks) safely and quickly after flight. PURPOSE: To describe neuromuscular function after short- and long-duration space flight. METHODS: To date, 5 crewmembers on short-duration (10- to 15-day) missions and 3 on long-duration missions have participated. Crewmembers were assessed 30 days before flight, on landing day (short-duration subjects only) and 1, 6, and 30 days after landing. The interpolated twitch technique, which utilizes a combination of maximal voluntary contractions and electrically evoked contractions, was used to assess the maximal voluntary isometric force (MIF) and central activation capacity of the knee extensors. Leg-press and bench-press devices were used to assess MIF and maximal dynamic power of the lower and upper body respectively. Specifically, power was measured during concentric-only ballistic throws of the leg-press sled and bench-press bar loaded to 40% and 30% of MIF respectively. RESULTS: Data are currently being collected from both Shuttle and ISS crewmembers. Emerging data indicate that measures of knee extensor muscle function are decreased with long-duration flight. DISCUSSION: The relationships between flight duration, neural drive, and muscle performance are of particular interest. Ongoing research will add to the current sample size and will focus on defining changes in muscle performance measures after long-duration space flight.

  12. Sandia National Laboratories/New Mexico Facilities and Safety Information Document [NOTE: Volume I, Chapter 1

    SciTech Connect

    March, F.; Guerrero, J.V.; Johns, W.H.; Schetnan, R.; Bayliss, L.S.; Kuzio, K.A.; White, B.B.

    1999-09-01

    Sandia National Laboratories (SNL) began in 1945 as the ''Z'' Division of what was then Los Alamos Scientific Laboratory on Oxnard Field, which was owned by the Air Technical Service Command, as a base of operations to store materials and house personnel. Oxnard Field was transferred to the U.S. Engineers, Manhattan District, on July 21, 1945, who converted several wood frame structures to serve functions that were transferred from Los Alamos. Development of the SNL/New Mexico (SNL/NM) site began in 1946 and 1947 with construction of the first four buildings in what is now Tech Area I. Construction of another 14 permanent buildings in Tech Area I began in 1948. SNL constructed a high-explosive assembly area in Tech Area II, a half mile south of Tech Area I, and started plans for several outdoor testing facilities for Tech Area III, about seven miles to the south of Tech Area I, in 1952. By 1953, SNL completed and put into operation the first group of Tech Area III facilities, which included a rocket sled track, a large centrifuge, a vibration facility, and an instrument control center. Tech Area IV and Tech Area V were developed later to provide facilities for pulsed power and high-energy experiments. As the need developed for outdoor testing facilities remote from the public and other work areas, SNL added many facilities on U.S. Air Force and other federal property in the area known as Coyote Test Field (Sandia National Laboratories, 1997b). Most recently, DOE leased U.S. Air Force facilities in the Manzano Area for SNL to use for storage of low-level radioactive waste, mixed waste (a combination of radioactive and hazardous waste), and transuranic waste (Sandia National Laboratories, 1997a).

  13. Survey report of NOAA Ship McArthur II cruises AR-04-04, AR-05-05 and AR-06-03: habitat classification of side scan sonar imagery in support of deep-sea coral/sponge explorations at the Olympic Coast National Marine Sanctuary

    USGS Publications Warehouse

    Intelmann, Steven S.; Cochrane, Guy R.; Bowlby, C. Edward; Brancato, Mary Sue; Hyland, Jeffrey

    2007-01-01

    Habitat mapping and characterization has been defined as a high-priority management issue for the Olympic Coast National Marine Sanctuary (OCNMS), especially for poorly known deep-sea habitats that may be sensitive to anthropogenic disturbance. As a result, a team of scientists from OCNMS, National Centers for Coastal Ocean Science (NCCOS), and other partnering institutions initiated a series of surveys to assess the distribution of deep-sea coral/sponge assemblages within the sanctuary and to look for evidence of potential anthropogenic impacts in these critical habitats. Initial results indicated that remotely delineating areas of hard bottom substrate through acoustic sensing could be a useful tool to increase the efficiency and success of subsequent ROV-based surveys of the associated deep-sea fauna. Accordingly, side scan sonar surveys were conducted in May 2004, June 2005, and April 2006 aboard the NOAA Ship McArthur II to: (1) obtain additional imagery of the seafloor for broader habitat-mapping coverage of sanctuary waters, and (2) help delineate suitable deep-sea coral-sponge habitat, in areas of both high and low commercial-fishing activities, to serve as sites for surveying-in more detail using an ROV on subsequent cruises, Several regions of the sea floor throughout the OCNMS were surveyed and mosaicked at 1-meter pixel resolution. Imagery from the side scan sonar mapping efforts was integrated with other complementary data from a towed camera sled, ROVs, sedentary samples, and bathymetry records to describe geological and biological (where possible) aspects of habitat. Using a hierarchical deep-water marine benthic classification scheme (Greene et al. 1999), we created a preliminary map of various habitat polygon features for use in a geographical information system (GIS). This report provides a description of the mapping and groundtruthing efforts as well as results of the image classification procedure for each of the areas surveyed.

  14. Comparison of the whiplash injury criteria.

    PubMed

    Ivancic, Paul C; Sha, Daohang

    2010-01-01

    Whiplash injury criteria are based upon the hypothesis that neck injuries are caused by excessive loads, displacements, or head/T1 relative acceleration and velocity. The objectives of this study were to evaluate and compare the whiplash injury criteria (IV-NIC, NIC, Nkm, Nij, and NDC) during simulated rear impacts of a new Human Model of the Neck (HUMON) with and without an active head restraint (AHR). HUMON consisted of a neck specimen mounted to the torso of BioRID II and carrying an anthropometric head stabilized with muscle force replication. HUMON was seated and secured in a Kia Sedona seat with AHR on a sled. Rear impacts (7.1 and 11.1g) were simulated with the AHR in five different positions followed by an impact with no HR. Statistical differences (P < 0.05) were determined in the peak NIC and NDC due to the AHR, as compared to no HR, and in the peak IV-NIC relative to physiologic limits. Linear regression analyses identified correlation between IV-NIC and NIC, Nkm, Nij, and NDC (R(2) > or = 0.35 and P < 0.001). The AHR caused significant decreases in peak NIC and NDC as compared to no HR. The IV-NIC identified significantly increased motion above the physiologic limit at the middle and lower cervical spine with and without the AHR. Correlation was observed between IV-NIC and NIC, Nkm, Nij, and NDC. Extrapolation using the present correlations and the IV-NIC injury thresholds suggests neck injuries may occur at peak NIC of 14.4m(2)/s(2), Nkm of 0.33, or Nij of 0.09. Nonphysiologic spinal rotation at one or more spinal levels may occur even if head/T1 motions are small. PMID:19887145

  15. Negative differential resistance devices for generation of terahertz radiation

    NASA Astrophysics Data System (ADS)

    Eisele, H.

    2015-08-01

    This paper discusses the principles of operation, state of the art, and future potential of active two-terminal devices for generation of low-noise, continuous-wave terahertz radiation. These devices use transit-time, transferred-electron, and quantum-mechanical effects (or a combination of them) to create a negative differential resistance (NDR) at the frequency of interest. Many different types of NDR devices have been proposed since the earliest days of semiconductor devices and studied in detailed simulations for their power generation potential, but have yet to be demonstrated experimentally. The paper focuses on NDR devices that not only yielded significant output powers at millimeter waves frequencies and higher, but also have the strong potential of generating radiation at terahertz frequencies. Examples of such NDR devices are resonant tunneling diodes (RTDs), superlattice electronic devices (SLEDs), and InP Gunn devices. Examples of their state-of-the-art results are output powers of 0.2 mW at 443 GHz and 5 μW at 1.53 THz from InGaAs/AlAs double barrier RTDs on InP substrate; 5.0 mW at 123.3 GHz, 1.1 mW at 155.1 GHz, and 0.52 mW at 252.8 GHz from GaAs/AlAs superlattice electronic devices on GaAs substrate; and 330 μW at 412 GHz, 86 μW at 479 GHz, and 18 μW at 502 GHz from InP Gunn devices.

  16. Analysis of spinal motion and loads during frontal impacts. Comparison between PMHS and ATD

    PubMed Central

    Lopez-Valdes, Francisco J.; Lau, Anthony; Lamp, John; Riley, Patrick; Lessley, David J.; Damon, Andrew; Kindig, Matthew; Kent, Richard; Balasubramanian, Sriram; Seacrist, Thomas; Maltese, Matthew R.; Arbogast, Kristy B.; Higuchi, Kazuo; Tanji, Hiro

    2010-01-01

    Quantifying the kinematics of the human spine during a frontal impact is a challenge due to the multi-degree-of-freedom structure of the vertebral column. This papers reports on a series of six frontal impacts sled tests performed on three Post Mortem Human Surrogates (PMHS). Each subject was exposed first to a low-speed, non-injurious frontal impact (9 km/h) and then to a high-speed one (40 km/h). Five additional tests were performed using the Hybrid III 50th percentile male ATD for comparison with the PMHS. A 3D motion capture system was used to record the 6-degree-of-freedom motion of body segments (head, T1, T8, L2, L4 and pelvis). The 3D trajectories of individual bony structures in the PMHS were determined using bone-mounted marker arrays, thus avoiding skin-attached markers and their potential measurements artifacts. The PMHS spines showed different behavior between low and high speed. While at low speed the head and upper spinal segments lagged the lower portion of the spine and pelvis in reaching their maximum forward displacement (time for maximum forward head excursion was 254.3±31.9 ms and 140.3±9 ms for the pelvis), these differences were minimal at high speed (127±2.6 ms for the head vs. 116.7±3.5 ms for the pelvis). The ATD did not exhibit this speed-dependant behavior. Furthermore, the ATD’s forward displacements were consistently less than those exhibited by the PMHS, regardless of the speed. Neck loads at the atlanto-occipital joint were estimated for the PMHS using inverse dynamics techniques and compared to those measured in the ATD. It was found that the axial and shear forces and the flexion moment at the upper neck of the PMHS were higher than those measured in the ATD. PMID:21050592

  17. Deflections from two types of Human Surrogates in Oblique Side Impacts

    PubMed Central

    Yoganandan, Narayan; Pintar, Frank A.

    2008-01-01

    The objective of the study was to obtain time-dependent thoracic and abdominal deflections of an anthropomorphic test device, the WorldSID dummy, in oblique impact using sled tests, and compare with post mortem human subject (PMHS) data. To simulate the oblique loading vector, the load wall was configured such that the thorax and abdominal plates were offset by twenty or thirty degrees. Deflections were obtained from a chestband placed at the middle thoracic level and five internal deflection transducers. Data were compared from the chestband and the transducer located at the same level of the thorax. In addition, data were compared with deflections from similar PMHS tests obtained using chestbands placed at the level of the axilla, xyphoid process, and tenth rib, representing the upper thorax, middle thorax, and abdominal region of the biological specimen. Peak deflections ranged from 30 to 85 mm in the dummy tests. Peak deflections ranged from 60 to 115 mm in PMHS. Under both obliquities, dummy deflection-time histories at the location along the chestband in close proximity to the internal deflection transducer demonstrated similar profiles. However, the peak deflection magnitudes from the chestband were approximately 20 mm greater than those from the internal transducer. Acknowledging that the chestband measures external deflections in contrast to the transducer which records internal ribcage deformations, peak deflections match from the two sensors. Deflection time histories were also similar between the dummy and PMHS in terms of morphology, although thoracic deflection magnitudes from the dummy matched more closely with PMHS than abdominal deflection magnitudes. The dummy deformed in such a way that peak deflections occurred along the lateral vector. This was in contrast to PMHS tests wherein maximum deflections occurred along the antero-lateral direction, suggesting differing deformation responses in the two models. In addition, peak deflections occurred

  18. Deflection measurement system for the hybrid iii six-year-old biofidelic abdomen.

    PubMed

    Gregory, T Stan; Howes, Meghan K; Rouhana, Stephen W; Hardy, Warren N

    2012-01-01

    Motor vehicle collisions are the leading cause of death for children ages 5 to 14. Enhancement of child occupant protection is partly dependent on the ability to accurately assess the interaction of child-size occupants with restraint systems. Booster seat design and belt fit are evaluated using child anthropomorphic test devices, such as the Hybrid III 6-year-old dummy., A biofidelic abdomen for the Hybrid III 6-year-old dummy is being developed by the Ford Motor Company to enhance the dummy’s ability to assess injury risk and further quantify submarining risk by measuring abdominal deflection. A practical measurement system for the biofidelic abdominal insert has been developed and demonstrated for three dimensional determination of abdominal deflection. Quantification of insert deflection is achieved via differential signal measurement using electrodes mounted within a conductive medium. Signal amplitude is proportional to the distance between the electrodes. A microcontroller is used to calculate distances between ventral electrodes and a dorsal electrode in three dimensions. This system has been calibrated statically, and its performance demonstrated in a series of sled tests. Deflection measurements from the instrumented abdominal insert indicate performance differences between two booster seat designs, yielding an average peak anterior to posterior displacement of the abdomen of 1.0 ± 3.4 mm and 31.2 ± 7.2 mm for the seats, respectively. Implementation of a 6-year-old abdominal insert with the ability to evaluate submarining potential will likely help safety researchers further enhance booster seat design and interaction with vehicle restraint systems , and help to further understand child occupant injury risk in automobile collisions. PMID:22846277

  19. Validation of the 5th and 95th Percentile Hybrid III Anthropomorphic Test Device Finite Element Model

    NASA Technical Reports Server (NTRS)

    Lawrence, C.; Somers, J. T.; Baldwin, M. A.; Wells, J. A.; Newby, N.; Currie, N. J.

    2014-01-01

    NASA spacecraft design requirements for occupant protection are a combination of the Brinkley criteria and injury metrics extracted from anthropomorphic test devices (ATD's). For the ATD injury metrics, the requirements specify the use of the 5th percentile female Hybrid III and the 95th percentile male Hybrid III. Furthermore, each of these ATD's is required to be fitted with an articulating pelvis and a straight spine. The articulating pelvis is necessary for the ATD to fit into spacecraft seats, while the straight spine is required as injury metrics for vertical accelerations are better defined for this configuration. The requirements require that physical testing be performed with both ATD's to demonstrate compliance. Before compliance testing can be conducted, extensive modeling and simulation are required to determine appropriate test conditions, simulate conditions not feasible for testing, and assess design features to better ensure compliance testing is successful. While finite element (FE) models are currently available for many of the physical ATD's, currently there are no complete models for either the 5th percentile female or the 95th percentile male Hybrid III with a straight spine and articulating pelvis. The purpose of this work is to assess the accuracy of the existing Livermore Software Technology Corporation's FE models of the 5th and 95th percentile ATD's. To perform this assessment, a series of tests will be performed at Wright Patterson Air Force Research Lab using their horizontal impact accelerator sled test facility. The ATD's will be placed in the Orion seat with a modified-advanced-crew-escape-system (MACES) pressure suit and helmet, and driven with loadings similar to what is expected for the actual Orion vehicle during landing, launch abort, and chute deployment. Test data will be compared to analytical predictions and modelling uncertainty factors will be determined for each injury metric. Additionally, the test data will be used to

  20. Kinematic Comparison of the Hybrid III and Q-Series Pediatric ATDs to Pediatric Volunteers in Low-Speed Frontal Crashes

    PubMed Central

    Seacrist, Thomas; Mathews, Emily A.; Samuels, Marina; García-España, J. Felipe; Longhitano, Douglas; St. Lawrence, Schuyler; Balasubramanian, Sriram; Maltese, Matthew R.; Arbogast, Kristy B.

    2012-01-01

    Previous research has suggested that the rigid pediatric ATD spine may not adequately represent the relatively mobile, multi-segmented spine of the child and thus may lead to important differences in the head trajectory of the ATD relative to a human. Recently we compared the responses of size-matched child volunteers to the Hybrid III 6-year-old ATD in low-speed frontal sled tests, illustrating differences in head, spinal, and pelvic kinematics as well as seating environment reaction loads. This paper expands this line of work to include comparisons between size-matched restrained child volunteers to the Hybrid III 10-year-old and the Q-series 6 and 10-year-old ATDs tested in the same low speed frontal environment. A 3-D near-infrared video target tracking system quantified the position of markers on the ATDs and volunteers(head top, nasion, external auditory meatus, C4, T1, and pelvis). Angular velocity of the head, seat belt forces, and reaction loads on the seat pan and foot rest were also measured. The Hybrid III 6 and Q6 exhibited significantly greater belt reaction loads compared to the pediatric volunteers, which exhibited greater seat pan shear. Compared to children, the Hybrid III 6 exhibited increased head rotation and similar head top and pelvic excursion, whereas the Q6 exhibited reductions in all three metrics. The Hybrid III 10 and Q10 ATDs exhibited reaction loads similar to the volunteers; however, excursions and head rotation were significantly reduced compared to volunteers. All pediatric ATDs exhibited significant reductions in C4 and T1excursions compared to the volunteers, likely due to the rigidity of the ATD thoracic spine. These analyses provide insight into aspects of ATD biofidelity in low-speed crash environments and illustrate differences in responses of the Hybrid III and Q-series pediatric ATDs. PMID:23169138

  1. Motion Perception and Manual Control Performance During Passive Tilt and Translation Following Space Flight

    NASA Technical Reports Server (NTRS)

    Clement, Gilles; Wood, Scott J.

    2010-01-01

    This joint ESA-NASA study is examining changes in motion perception following Space Shuttle flights and the operational implications of post-flight tilt-translation ambiguity for manual control performance. Vibrotactile feedback of tilt orientation is also being evaluated as a countermeasure to improve performance during a closed-loop nulling task. METHODS. Data has been collected on 5 astronaut subjects during 3 preflight sessions and during the first 8 days after Shuttle landings. Variable radius centrifugation (216 deg/s) combined with body translation (12-22 cm, peak-to-peak) is utilized to elicit roll-tilt perception (equivalent to 20 deg, peak-to-peak). A forward-backward moving sled (24-390 cm, peak-to-peak) with or without chair tilting in pitch is utilized to elicit pitch tilt perception (equivalent to 20 deg, peak-to-peak). These combinations are elicited at 0.15, 0.3, and 0.6 Hz for evaluating the effect of motion frequency on tilt-translation ambiguity. In both devices, a closed-loop nulling task is also performed during pseudorandom motion with and without vibrotactile feedback of tilt. All tests are performed in complete darkness. PRELIMINARY RESULTS. Data collection is currently ongoing. Results to date suggest there is a trend for translation motion perception to be increased at the low and medium frequencies on landing day compared to pre-flight. Manual control performance is improved with vibrotactile feedback. DISCUSSION. The results of this study indicate that post-flight recovery of motion perception and manual control performance is complete within 8 days following short-duration space missions. Vibrotactile feedback of tilt improves manual control performance both before and after flight.

  2. Aqueous glucose measurement using differential absorption-based frequency domain optical coherence tomography at wavelengths of 1310 nm and 1625 nm

    NASA Astrophysics Data System (ADS)

    John, Pauline; Manoj, Murali; Sujatha, N.; Vasa, Nilesh J.; Rao, Suresh R.

    2015-07-01

    This work presents a combination of differential absorption technique and frequency domain optical coherence tomography for detection of glucose, which is an important analyte in medical diagnosis of diabetes. Differential absorption technique is used to detect glucose selectively in the presence of interfering species especially water and frequency domain optical coherence tomography (FDOCT) helps to obtain faster acquisition of depth information. Two broadband super-luminescent diode (SLED) sources with centre wavelengths 1586 nm (wavelength range of 1540 to 1640 nm) and 1312 nm (wavelength range of 1240 to 1380 nm) and a spectral width of ≍ 60 nm (FWHM) are used. Preliminary studies on absorption spectroscopy using various concentrations of aqueous glucose solution gave promising results to distinguish the absorption characteristics of glucose at two wavelengths 1310 nm (outside the absorption band of glucose) and 1625 nm (within the absorption band of glucose). In order to mimic the optical properties of biological skin tissue, 2% and 10% of 20% intralipid with various concentrations of glucose (0 to 4000 mg/dL) was prepared and used as sample. Using OCT technique, interference spectra were obtained using an optical spectrum analyzer with a resolution of 0.5 nm. Further processing of the interference spectra provided information on reflections from the surfaces of the cuvette containing the aqueous glucose sample. Due to the absorption of glucose in the wavelength range of 1540 nm to 1640 nm, a trend of reduction in the intensity of the back reflected light was observed with increase in the concentration of glucose.

  3. The ecology of xenophyophores (Protista) on eastern Pacific seamounts

    NASA Astrophysics Data System (ADS)

    Levin, Lisa A.; Thomas, Cynthia L.

    1988-12-01

    Large, agglutinating protozoans of the class Xenophyophorea are the dominant epifaunal organisms on soft and hard substrates of many bathyal seamounts in the eastern Pacific Ocean off Mexico. Observations made with the submersible Alvin and remotely towed camera sleds on 17 seamounts at 31°, 20°, 13° and 10°N revealed more than ten distinct xenophyophore test morphologies. Most of these appear to represent previously undescribed species. Reticulate forms are numerically dominant at 20°, 13° and 10°N. Xenophyophore abundances increase with decreasing latitude, being rare at 30°N, present at densities of 0.1-1.0 m -2 at 20° and 13°N and often exceeding 1.0 m -2 at 10°N, occasionally reaching 10-18 m -2. Highest concentrations are observed on caldera floors near the base of steep caldera walls, at depths between 1700 and 2500 m. Most individuals select sand-size pelagic foraminiferan tests (63-500 μm) and exclude pebble, silt and clay-size particles for test construction. Xenophyophore on seamounts modify the structure of metazoan communities and may play a role in maintenance of infaunal diversity. Twenty-seven xenophyophore tests were found to provide habitat for 16 major macrofaunal taxa (152 individuals) and three meiofaunal taxa (333 individuals). The presence of xenophyophores also enhances the abundance of isopods, tanaids, ophiuroids, nematodes and harpacticoid copepods dwelling in sediments surrounding the tests. Mobile megafauna are attracted to sediment beneath and adjacent to xenophyophores. We suggest that xenophyophores, which are abundant on many topographic features in deep water (e.g. guyots, trenches, canyons and continental slopes), are a functionally important component of deep-sea benthic communities and require further autecological and synecological investigation.

  4. The effect of stanozolol on 15nitrogen retention in the dog.

    PubMed Central

    Olson, M E; Morck, D W; Quinn, K B

    2000-01-01

    The objective of the study was to determine the influence of either oral or intramuscular administration of stanozolol on nitrogen retention in dogs by using a non-invasive 15N-amino acid tracer technique. Ten healthy, intact, adult male sled dogs received either stanozolol tablets, 2 mg/dog PO, q12h, for 25 days (Group 1, n = 5) or an intramuscular injection of 25 mg of stanozolol on Days 7, 14, 21, and 28 (Group 2, n = 5). A 15N amino acid (5.27 mmol) was infused intravenously into each dog on Day 0 (before stanozolol treatment) and on Day 31 (after stanozolol treatment). Urine was collected by catheterization from each animal 3 times daily for 3 consecutive days. The 15N-urea enrichment in urine was determined by high-resolution mass spectrometry and the total amount of urea in the urine was determined. Both oral and injectable stanozolol resulted in significant (P < 0.05) increases in amino acid nitrogen retention compared to pretreatment values. Oral stanozolol increased nitrogen retention from 29.2 +/- 8.2% to 50.3 +/- 9.2%, while stanozolol injection increased nitrogen retention from 26.6 +/- 9.9% to 67.0 +/- 7.5%. The response to intramuscular administration was significantly greater than the response to the oral dosing regime. Stanozolol increases amino acid nitrogen retention in dogs, as has been previously observed in rats. This action of stanozolol may be beneficial in dogs under stress of surgical trauma and chronic disease. PMID:11041505

  5. Management of fluid mud in estuaries, bays, and lakes. II: Measurement, modeling, and management

    USGS Publications Warehouse

    McAnally, W.H.; Teeter, A.; Schoellhamer, D.; Friedrichs, C.; Hamilton, D.; Hayter, E.; Shrestha, P.; Rodriguez, H.; Sheremet, A.; Kirby, R.

    2007-01-01

    Techniques for measurement, modeling, and management of fluid mud are available, but research is needed to improve them. Fluid mud can be difficult to detect, measure, or sample, which has led to new instruments and new ways of using existing instruments. Multifrequency acoustic fathometers sense neither density nor viscosity and are, therefore, unreliable in measuring fluid mud. Nuclear density probes, towed sleds, seismic, and drop probes equipped with density meters offer the potential for accurate measurements. Numerical modeling of fluid mud requires solving governing equations for flow velocity, density, pressure, salinity, water surface, plus sediment submodels. A number of such models exist in one-, two-, and three-dimensional form, but they rely on empirical relationships that require substantial site-specific validation to observations. Management of fluid mud techniques can be classified as those that accomplish: Source control, formation control, and removal. Nautical depth, a fourth category, defines the channel bottom as a specific fluid mud density or alternative parameter as safe for navigation. Source control includes watershed management measures to keep fine sediment out of waterways and in-water measures such as structures and traps. Formation control methods include streamlined channels and structures plus other measures to reduce flocculation and structures that train currents. Removal methods include the traditional dredging and transport of dredged material plus agitation that contributes to formation control and/or nautical depth. Conditioning of fluid mud by dredging and aerating offers the possibility of improved navigability. Two examples-the Atchafalaya Bar Channel and Savannah Harbor-illustrate the use of measurements and management of fluid mud. ?? 2007 ASCE.

  6. Laser tracker TSPI uncertainty quantification via centrifuge trajectory

    NASA Astrophysics Data System (ADS)

    Romero, Edward; Paez, Thomas; Brown, Timothy; Miller, Timothy

    2009-08-01

    Sandia National Laboratories currently utilizes two laser tracking systems to provide time-space-position-information (TSPI) and high speed digital imaging of test units under flight. These laser trackers have been in operation for decades under the premise of theoretical accuracies based on system design and operator estimates. Advances in optical imaging and atmospheric tracking technology have enabled opportunities to provide more precise six degree of freedom measurements from these trackers. Applying these technologies to the laser trackers requires quantified understanding of their current errors and uncertainty. It was well understood that an assortment of variables contributed to laser tracker uncertainty but the magnitude of these contributions was not quantified and documented. A series of experiments was performed at Sandia National Laboratories large centrifuge complex to quantify TSPI uncertainties of Sandia National Laboratories laser tracker III. The centrifuge was used to provide repeatable and economical test unit trajectories of a test-unit to use for TSPI comparison and uncertainty analysis. On a centrifuge, testunits undergo a known trajectory continuously with a known angular velocity. Each revolution may represent an independent test, which may be repeated many times over for magnitudes of data practical for statistical analysis. Previously these tests were performed at Sandia's rocket sled track facility but were found to be costly with challenges in the measurement ground truth TSPI. The centrifuge along with on-board measurement equipment was used to provide known ground truth position of test units. This paper discusses the experimental design and techniques used to arrive at measures of laser tracker error and uncertainty.

  7. Crash pulse recorder--validation in full scale crash tests.

    PubMed

    Kullgren, A; Lie, A; Tingvall, C

    1995-10-01

    Estimation of the accident severity is a fundamental requirement in accident reconstruction and analysis. Accident severity can be measured in many different ways, but in frontal collisions change of velocity, energy equivalent speed or equivalent barrier speed are frequently used parameters. These parameters are most often estimated from vehicle deformation. It is known, however, that the quality of these estimates is limited if compared with these obtained in laboratory test conditions. To be able to achieve almost the same measurements and measurement accuracy in real-life accidents as in the laboratory, where the acceleration time history is measured, an on-board measurement technique is required. This presentation gives results of tests of a low cost device for measuring the crash pulse for a car involved in an accident, concerning systematic and random error. The device, called the Crash Pulse Recorder (CPR), has been tested previously in several sled tests. The CPR is based on measurement of the movement of the mass in a spring mass system in a collision. A brief description of its construction is also included. The CPR is an integral part of a large accident data collection system including interior and exterior deformation measurements and evaluation of injury outcome. This report presents the results of several full-scale crash tests, undertaken to evaluate the accuracy and precision of the CPR in cars in different impact modes. The tests comprised both offset and angled collisions. Most of the tests were car to car collisions, but barrier tests were also performed. The random error of the CPR was found to be 2.2 km/hr for the delta V measurements and 0.6 g for mean acceleration. PMID:8579702

  8. Importance of physical and hydraulic characteristics to unionid mussels: A retrospective analysis in a reach of large river

    USGS Publications Warehouse

    Zigler, S.J.; Newton, T.J.; Steuer, J.J.; Bartsch, M.R.; Sauer, J.S.

    2008-01-01

    Interest in understanding physical and hydraulic factors that might drive distribution and abundance of freshwater mussels has been increasing due to their decline throughout North America. We assessed whether the spatial distribution of unionid mussels could be predicted from physical and hydraulic variables in a reach of the Upper Mississippi River. Classification and regression tree (CART) models were constructed using mussel data compiled from various sources and explanatory variables derived from GIS coverages. Prediction success of CART models for presence-absence of mussels ranged from 71 to 76% across three gears (brail, sled-dredge, and dive-quadrat) and 51% of the deviance in abundance. Models were largely driven by shear stress and substrate stability variables, but interactions with simple physical variables, especially slope, were also important. Geospatial models, which were based on tree model results, predicted few mussels in poorly connected backwater areas (e.g., floodplain lakes) and the navigation channel, whereas main channel border areas with high geomorphic complexity (e.g., river bends, islands, side channel entrances) and small side channels were typically favorable to mussels. Moreover, bootstrap aggregation of discharge-specific regression tree models of dive-quadrat data indicated that variables measured at low discharge were about 25% more predictive (PMSE = 14.8) than variables measured at median discharge (PMSE = 20.4) with high discharge (PMSE = 17.1) variables intermediate. This result suggests that episodic events such as droughts and floods were important in structuring mussel distributions. Although the substantial mussel and ancillary data in our study reach is unusual, our approach to develop exploratory statistical and geospatial models should be useful even when data are more limited. ?? 2007 Springer Science+Business Media B.V.

  9. Postural responses exhibit multisensory dependencies with discordant visual and support surface motion.

    PubMed

    Keshner, Emily A; Kenyon, Robert V; Langston, Jessica

    2004-01-01

    The purpose of this study was to identify how the postural system weights coincident yet discordant disturbances of the visual and proprioceptive/vestibular systems. Eleven healthy subjects (25-38 yrs) received either fore-aft translations of an immersive, wide field-of-view visual environment (0.1 Hz, +/- 3.7 m/sec), or anterior-posterior translations of the support surface (0.25 Hz, +/- 15 cm/sec), or both concurrently. Kinematics of the head, trunk, and shank were collected with an Optotrak system and angular motion of each segment plotted across time. With only support surface translation, segmental responses were small (1 degrees -2 degrees ) and mostly opposed the direction of sled translation. When only the visual scene was moving, segmental responses increased as the trial progressed. When the inputs were presented coincidentally, response amplitudes were large even at the onset of the trial. Mean RMS values across subjects were significantly greater with combined stimuli than for either stimulus presented alone and areas under the power curve across subjects were significantly increased at the frequency of the visual input when both inputs were presented. Thus, intra-modality dependencies were observed, such that responses to the visual inputs significantly increased and responses to the somatosensory signals reflected the stimulus amplitude only when the two inputs were combined. We believe it unlikely that the role of any single pathway contributing to postural control can be accurately characterized in a static environment if the function of that pathway is context dependent. PMID:15328445

  10. Analysis of towed camera images to determine the effects of disposed mustard-filled bombs on the deep water benthic community off south Oahu

    NASA Astrophysics Data System (ADS)

    Kelley, Christopher; Carton, Geoffrey; Tomlinson, Michael; Gleason, Arthur

    2016-06-01

    Still images from a towed camera sled were used to evaluate the potential ecological effects of M47A2 mustard-filled (1,1‧-thiobis[2-chloroethane]) bombs disposed of in over 500 m of water off the south coast of Oahu in 1944. The types of munitions and munitions debris in the images were identified by an ordnance and explosives safety specialist. To the extent feasible, non-munitions related debris were also identified. Biologists then examined the images and identified the types and numbers of animals: (1) on or near (<1 m) the M47A2 bombs; (2) on other manmade debris, including other munitions; and (3) on the natural substrate that was predominantly sediment with little, if any, topographic relief. Multivariate statistical techniques were used to analyze these data to identify differences between the biota inhabiting the three substrates. The analysis indicated that the types and numbers of animals associated with the M47A2 bombs were not significantly different from those observed on other types of munitions and other manmade debris; however they were significantly different from the animals found only on the natural sediment. Based on these results, it appears that the mustard-filled bombs are providing hard substrate similar to other disposed objects, attracting "hard substrate species" that would not have otherwise colonized the area. Even though it is apparent that many of the mustard-filled bombs have breached and their contents exposed, the analysis did not find any evidence of animals avoiding the mustard-filled bombs.

  11. Headless submarine canyons and fluid flow on the toe of the Cascadia accretionary complex

    USGS Publications Warehouse

    Orange, D.L.; McAdoo, B.G.; Moore, J.C.; Tobin, H.; Screaton, E.; Chezar, H.; Lee, H.; Reid, M.; Vail, R.

    1997-01-01

    Headless submarine canyons with steep headwalls and shallowly sloping floors occur on both the second and third landward vergent anticlines on the toe of the Cascadia accretionary complex off central Oregon (45 ??N, 125?? 30??W). In September 1993, we carried out a series of nine deep tow camera sled runs and nine ALVIN dives to examine the relationship between fluid venting, structure and canyon formation. We studied four canyons on the second and third landward vergent anticlines, as well as the apparently unfailed intercanyon regions along strike. All evidence of fluid expulsion is associated with the canyons; we found no evidence of fluid flow between canyons. Even though all fluid seeps are related to canyons, we did not find seeps in all canyons, and the location of the seeps within the canyons differed. On the landward facing limb of the second landward vergent anticline a robust cold seep community occurs at the canyon's inflection point. This seep is characterized by chemosynthetic vent clams, tube worms and extensive authigenic carbonate. Fluids for this seep may utilize high-permeability flow paths either parallel to bedding within the second thrust ridge or along the underlying thrust fault before leaking into the overriding section. Two seaward facing canyons on the third anticlinal ridge have vent clam communities near the canyon mouths at approximately the intersection between the anticlinal ridge and the adjacent forearc basin. No seeps were found along strike at the intersection of the slope basin and anticlinal ridge. We infer that the lack of seepage along strike and the presence of seeps in canyons may be related to fluid flow below the forearc basin/slope unconformity (overpressured by the impinging thrust fault to the west?) directed toward canyons at the surface.

  12. Developing an Algorithm for Finding Deep-Sea Corals on Seamounts Using Bathymetry and Photographic Data

    NASA Astrophysics Data System (ADS)

    Fernandez, D. P.; Adkins, J. F.; Scheirer, D. P.

    2006-12-01

    Over the last three years we have conducted several cruises on seamounts in the North Atlantic to sample and characterize the distribution of deep-sea corals in space and time. Using the deep submergence vehicle Alvin and the ROV Hercules we have spent over 80 hours on the seafloor. With the autonomous vehicle ABE and a towed camera sled, we collected over 10,000 bottom photographs and over 60 hours of micro- bathymetry over 120 km of seafloor. While there are very few living scleractinia (Desmophyllum dianthus, Solenosmilia sp. and, Lophilia sp.), we recovered over 5,000 fossil D. dianthus and over 60 kg of fossil Solenosmilia sp. The large numbers of fossil corals mean that a perceived lack of material does not have to limit the use of this new archive of the deep ocean. However, we need a better strategy for finding and returning samples to the lab. Corals clearly prefer to grow on steep slopes and at the tops of scarps of all scales. They are preferentially found along ridges and on small knolls flanking a larger edifice. There is also a clear preference for D. dianthus to recruit onto carbonate substrate. Overall, our sample collection, bathymetry and bottom photographs allow us to create an algorithm for finding corals based only on knowledge of the seafloor topography. We can test this algorithm against known sampling locations and visual surveys of the seafloor. Similar to the way seismic data are used to locate ideal coring locations, we propose that high-resolution bathymetry can be used to predict the most likely locations for finding fossil deep-sea corals.

  13. Strong Depth-Related Zonation of Megabenthos on a Rocky Continental Margin (∼700–4000 m) off Southern Tasmania, Australia

    PubMed Central

    Thresher, Ronald; Althaus, Franziska; Adkins, Jess; Gowlett-Holmes, Karen; Alderslade, Phil; Dowdney, Jo; Cho, Walter; Gagnon, Alex; Staples, David; McEnnulty, Felicity; Williams, Alan

    2014-01-01

    Assemblages of megabenthos are structured in seven depth-related zones between ∼700 and 4000 m on the rocky and topographically complex continental margin south of Tasmania, southeastern Australia. These patterns emerge from analysis of imagery and specimen collections taken from a suite of surveys using photographic and in situ sampling by epibenthic sleds, towed video cameras, an autonomous underwater vehicle and a remotely operated vehicle (ROV). Seamount peaks in shallow zones had relatively low biomass and low diversity assemblages, which may be in part natural and in part due to effects of bottom trawl fishing. Species richness was highest at intermediate depths (1000–1300 m) as a result of an extensive coral reef community based on the bioherm-forming scleractinian Solenosmilia variabilis. However, megabenthos abundance peaked in a deeper, low diversity assemblage at 2000–2500 m. The S. variabilis reef and the deep biomass zone were separated by an extensive dead, sub-fossil S. variabilis reef and a relatively low biomass stratum on volcanic rock roughly coincident with the oxygen minimum layer. Below 2400 m, megabenthos was increasingly sparse, though punctuated by occasional small pockets of relatively high diversity and biomass. Nonetheless, megabenthic organisms were observed in the vast majority of photographs on all seabed habitats and to the maximum depths observed - a sandy plain below 3950 m. Taxonomic studies in progress suggest that the observed depth zonation is based in part on changing species mixes with depth, but also an underlying commonality to much of the seamount and rocky substrate biota across all depths. Although the mechanisms supporting the extraordinarily high biomass in 2000–2500 m depths remains obscure, plausible explanations include equatorwards lateral transport of polar production and/or a response to depth-stratified oxygen availability. PMID:24465758

  14. Predicting rib fracture risk with whole-body finite element models: development and preliminary evaluation of a probabilistic analytical framework.

    PubMed

    Forman, Jason L; Kent, Richard W; Mroz, Krystoffer; Pipkorn, Bengt; Bostrom, Ola; Segui-Gomez, Maria

    2012-01-01

    This study sought to develop a strain-based probabilistic method to predict rib fracture risk with whole-body finite element (FE) models, and to describe a method to combine the results with collision exposure information to predict injury risk and potential intervention effectiveness in the field. An age-adjusted ultimate strain distribution was used to estimate local rib fracture probabilities within an FE model. These local probabilities were combined to predict injury risk and severity within the whole ribcage. The ultimate strain distribution was developed from a literature dataset of 133 tests. Frontal collision simulations were performed with the THUMS (Total HUman Model for Safety) model with four levels of delta-V and two restraints: a standard 3-point belt and a progressive 3.5-7 kN force-limited, pretensioned (FL+PT) belt. The results of three simulations (29 km/h standard, 48 km/h standard, and 48 km/h FL+PT) were compared to matched cadaver sled tests. The numbers of fractures predicted for the comparison cases were consistent with those observed experimentally. Combining these results with field exposure informantion (ΔV, NASS-CDS 1992-2002) suggests a 8.9% probability of incurring AIS3+ rib fractures for a 60 year-old restrained by a standard belt in a tow-away frontal collision with this restraint, vehicle, and occupant configuration, compared to 4.6% for the FL+PT belt. This is the first study to describe a probabilistic framework to predict rib fracture risk based on strains observed in human-body FE models. Using this analytical framework, future efforts may incorporate additional subject or collision factors for multi-variable probabilistic injury prediction. PMID:23169122

  15. Predicting Rib Fracture Risk With Whole-Body Finite Element Models: Development and Preliminary Evaluation of a Probabilistic Analytical Framework

    PubMed Central

    Forman, Jason L.; Kent, Richard W.; Mroz, Krystoffer; Pipkorn, Bengt; Bostrom, Ola; Segui-Gomez, Maria

    2012-01-01

    This study sought to develop a strain-based probabilistic method to predict rib fracture risk with whole-body finite element (FE) models, and to describe a method to combine the results with collision exposure information to predict injury risk and potential intervention effectiveness in the field. An age-adjusted ultimate strain distribution was used to estimate local rib fracture probabilities within an FE model. These local probabilities were combined to predict injury risk and severity within the whole ribcage. The ultimate strain distribution was developed from a literature dataset of 133 tests. Frontal collision simulations were performed with the THUMS (Total HUman Model for Safety) model with four levels of delta-V and two restraints: a standard 3-point belt and a progressive 3.5–7 kN force-limited, pretensioned (FL+PT) belt. The results of three simulations (29 km/h standard, 48 km/h standard, and 48 km/h FL+PT) were compared to matched cadaver sled tests. The numbers of fractures predicted for the comparison cases were consistent with those observed experimentally. Combining these results with field exposure informantion (ΔV, NASS-CDS 1992–2002) suggests a 8.9% probability of incurring AIS3+ rib fractures for a 60 year-old restrained by a standard belt in a tow-away frontal collision with this restraint, vehicle, and occupant configuration, compared to 4.6% for the FL+PT belt. This is the first study to describe a probabilistic framework to predict rib fracture risk based on strains observed in human-body FE models. Using this analytical framework, future efforts may incorporate additional subject or collision factors for multi-variable probabilistic injury prediction. PMID:23169122

  16. The INAF/IAPS Plasma Chamber for ionospheric simulation experiment

    NASA Astrophysics Data System (ADS)

    Diego, Piero

    2016-04-01

    The plasma chamber is particularly suitable to perform studies for the following applications: - plasma compatibility and functional tests on payloads envisioned to operate in the ionosphere (e.g. sensors onboard satellites, exposed to the external plasma environment); - calibration/testing of plasma diagnostic sensors; - characterization and compatibility tests on components for space applications (e.g. optical elements, harness, satellite paints, photo-voltaic cells, etc.); - experiments on satellite charging in a space plasma environment; - tests on active experiments which use ion, electron or plasma sources (ion thrusters, hollow cathodes, field effect emitters, plasma contactors, etc.); - possible studies relevant to fundamental space plasma physics. The facility consists of a large volume vacuum tank (a cylinder of length 4.5 m and diameter 1.7 m) equipped with a Kaufman type plasma source, operating with Argon gas, capable to generate a plasma beam with parameters (i.e. density and electron temperature) close to the values encountered in the ionosphere at F layer altitudes. The plasma beam (A+ ions and electrons) is accelerated into the chamber at a velocity that reproduces the relative motion between an orbiting satellite and the ionosphere (≈ 8 km/s). This feature, in particular, allows laboratory simulations of the actual compression and depletion phenomena which take place in the ram and wake regions around satellites moving through the ionosphere. The reproduced plasma environment is monitored using Langmuir Probes (LP) and Retarding Potential Analyzers (RPA). These sensors can be automatically moved within the experimental space using a sled mechanism. Such a feature allows the acquisition of the plasma parameters all around the space payload installed into the chamber for testing. The facility is currently in use to test the payloads of CSES satellite (Chinese Seismic Electromagnetic Satellite) devoted to plasma parameters and electric field

  17. A Microseismometer for Penetrometer Deployment in the Jupiter System

    NASA Astrophysics Data System (ADS)

    Pike, William; Standley, Ian; Karl, Werner; Delahunty, Aifric; Calcutt, Simon

    2010-05-01

    The internal structure of the moons of Jupiter is an area of great interest. Seismic investigations, either in the long-period band of 0.1 to 1 Hz, or at shorter periods of 1 to 100 Hz, have been studied as a means to determine the depth of subsurface liquid water with a single, triaxial seismometer. A penetrometer would be an ideal deployment for such an instrument as it would ensure excellent coupling, minimise thermal variations, and substantially reduce the radiation environment during operation. A microseismometer is under development which combines the required sensitivity for identification of the ambient seismicity with the robustness to survive the shock of deployment. At the heart of the instrument is a single-crystal silicon suspension machined through the full thickness of a wafer resulting in a very high quality factor. The movement of the proof mass is determined by extremely sensitive capacitive array transducer. This transducer is coupled to readout and feedback electronics which are designed for very low power operation. A unique combination of open and closed loop feedback enables the instrument to operate over a wide range of tilt angles, a vital consideration for a penetrometer deployment. The current measured noise is 3 ng/sqrtHz at 20 s, with the capability of a further order of magnitude improvement. The suspension has been tested on rocket-sled impacts to simulate a penetrometer deployment, surviving shocks up to 14,000 g with suitable encapsulation. Such an instrument would have the capability for deployment on the surface of Europa or Ganymede and should provide vital information on the internal structure of these bodies.

  18. High-precision beam shaper for coherent and incoherent light using a DLP spatial light modulator

    NASA Astrophysics Data System (ADS)

    Liang, Jinyang; Kohn, Rudolph N., Jr.; Becker, Michael F.; Heinzen, Daniel J.

    2011-03-01

    We designed a precision laser beam shaper using a Texas Instruments digital micromirror device (DMD) with a telescope system containing a pinhole low-pass filter. The performance of the beam shaper was measured by comparing the intensity and wave-front uniformity to the target function and by the energy conversion efficiency. We demonstrated flattop and other laser beam profiles with 1-1.5% root-mean-square (RMS) error for a raw camera image and nearly flat phase. A noise analysis of the system revealed that lower error is possible and that most of the error came from coherent speckle noise in the camera. A previous experiment using a 1064 nm single-mode fiber (SMF) laser produced around 7% beam power conversion efficiency. Here we report improvements in system automation and laser source flexibility that result in increasing both the speed of the system to calculate and produce a beam, and the beam uniformity and energy conversion efficiency. A LabVIEW program was written to accelerate the speed of the iterative process for beam profile refinement. A 760 nm super-luminescent light emitting diode (SLED) and a 781 nm Laser Diode (LD) were used as light sources in order to reduce the beam coherence and approach the ultimate performance of the shaper. Both sources greatly reduced the speckle noise and increased measured intensity uniformity. Experiments achieved less than 0.9% RMS error over the entire flattop area with a diameter of 1.32 mm. In addition, simulations were conducted to determine the optimized wavelengths for different types of DMDs. For the .7XGA DMD, the 5th diffraction order matches 750-800 nm. Matching the laser diode to this wavelength increased the power conversion efficiency (input beam to output beam) to 19.8%.

  19. Modelling the Backscatter Response of Different Zones Within a Polar Glacier

    NASA Astrophysics Data System (ADS)

    Langley, K.; Meuller, K.; Brandt, O.; Hamran, E.

    2005-12-01

    In order to better quantify the causes of backscatter in glaciers, we model the backscatter response of a polar glacier to C-band GPR imaging. The motivation for such modeling is the need to develop improved algorithms for glacier parameter retrieval from SAR data, including snow facies type, accumulation rate, etc.. These efforts require a better understanding of C-band scattering mechanisms in relation to snow physical processes and determining more accurate quantitive relationships between backscatter and snow physical parameters. Profiling was done on Kongsvegen glacier, northwest Svalbard using a sled-mounted radar towed behind a skidoo. Averaged traces are taken from each of three key zones of the glacier: ablation area; superimposed ice zone; and the firn area. We define a model for each of the areas based on information from ice cores and velocity profiles from CMPs, obtained at the same time as the GPR profiles. Model variables such as air bubble and ice inclusion size, shape, orientation and fractional volume, and interface roughness are varied within limits set by the field observation. Our model builder `modelGPR' allows fast creation of complex subsurface models including multiple rough layers and statistically distributed inhomogeneities. The response of the models to an electromagnetic wave is calculated by the FDTD software GprMax. We calculate the backscatter energy and compare the resultant trace to the measured GPR trace. A systematic trial and error approach is taken to find the best fit between the synthetic scans and the real data. Comparing response due to volume scattering from air bubbles with scattering from rough snow/ice or ice/ice interfaces provides new perspectives for long-term monitoring of polar glaciers.

  20. High energy particles at Mars and Venus: Phobos-2, Mars Express and Venus Express observations and their interpretation by hybrid model simulations

    NASA Astrophysics Data System (ADS)

    McKenna-Lawlor, Susan; Kallio, Esa; Fram, Rudy A.; Alho, Markku; Jarvinen, Riku; Dyadechkin, Sergey; Wedlund, Cyril Simon; Zhang, Tielong; Collinson, Glyn A.; Futaana, Yoshifumi

    2013-04-01

    Mars and Venus can both be reached by Solar Energetic Particles (SEPs). Such high energy particles (protons, multiply charged heavy ions, electrons) penetrate the upper atmospheres of Mars and Venus because, in contrast to Earth, these bodies do not have a significant, global, intrinsic magnetic field to exclude them. One especially well documented, complex and prolonged SEP took in place in early 1989 (Solar Cycle 23) when the Phobos-2 spacecraft was orbiting Mars. This spacecraft had a dedicated high energy particle instrument onboard (SLED), which measured particles with energies in the keV range up to a few tens of MeV. There was in addition a magnetometer as well as solar wind plasma detectors onboard which together provided complementary data to support contemporaneous studies of the background SEP environment. Currently, while the Sun is displaying maximum activity (Solar Cycle 24), Mars and Venus are being individually monitored by instrumentation flown onboard the Mars Express (MEX) and Venus Express (VEX) spacecraft. Neither of these spacecraft carry a high energy particle instrument but their Analyzer of Space Plasmas and Energetic Atoms (ASPERA) experiments (ASPERA-3 on MEX and ASPERA-4 on VEX), can be used to study SEPs integrated over E ≥ ~30 MeV which penetrate the instrument hardware and form background counts in the plasma data. In the present work we present SEP events measured at Mars and Venus based on Phobos-2, 1989 data and on, more recent, MEX and VEX (identified from particle background) observations. We further introduce numerical global SEP simulations of the measured events based on 3-D self-consistent hybrid models (HYB-Mars and HYB-Venus). Through comparing the in situ SEP observations with these simulations, new insights are provided into the properties of the measured SEPs as well as into how their individual planetary bow shocks and magnetospheres affect the characteristics of their ambient Martian and Venusian SEP environments.