WorldWideScience

Sample records for absolute plate motion

  1. New Reference Models for Pacific Absolute Plate Motion

    Science.gov (United States)

    Wessel, P.

    2012-12-01

    Absolute plate motion (APM) models are commonly derived by assuming that age-progressive seamount chains represent the surface expressions of mantle plumes; the chain geometries thus record the relative motion between plumes and plates. Traditionally, plumes have been assigned zero motion (i.e., the fixed hotspot hypothesis), and with this assumption the trails directly reflect plate motion. However, since the early 1970s arguments from sedimentary facies and marine magnetics have been marshaled against the fixity of hotspots, perhaps culminating with more recent and direct inferences of anomalous paleolatitudes for several seamounts in both the Emperor and Louisville chains. These data can broadly be explained by drifting plumes, but paleomagnetic data remain scarce and may allow for some true polar wander; furthermore, several age progressions are incomplete or inconsistent and the present locations of some hotspots are uncertain. Finally, APM models with moving hotspots derive largely from mantle flow modeling whose predictions do not match observations directly. Here, I present new absolute plate motion models for the Pacific plate back to 150 Ma. The first model assumes fixed hotspots and is meant to serve as a reference model representing the classic fixed hotspot hypothesis. It is an updated version of the Wessel and Kroenke [2008] model but now including all available chains, recently published age data and processed using improved modeling techniques. The second model uses the same data but also attempts to honor available data on hotspot mobility. It is intended to be a "work in progress" model that will be updated as additional paleolatitude or age data become available. These models can serve as test beds for tectonic hypothesis and be used to identify seamount chain segments where additional paleomagnetic or age observations would have the most impact.

  2. Hybrid method for consistent model of the Pacific absolute plate motion and a test for inter-hotspot motion since 70Ma

    Science.gov (United States)

    Harada, Y.; Wessel, P.; Sterling, A.; Kroenke, L.

    2002-12-01

    Inter-hotspot motion within the Pacific plate is one of the most controversial issues in recent geophysical studies. However, it is a fact that many geophysical and geological data including ages and positions of seamount chains in the Pacific plate can largely be explained by a simple model of absolute motion derived from assumptions of rigid plates and fixed hotspots. Therefore we take the stand that if a model of plate motion can explain the ages and positions of Pacific hotspot tracks, inter-hotspot motion would not be justified. On the other hand, if any discrepancies between the model and observations are found, the inter-hotspot motion may then be estimated from these discrepancies. To make an accurate model of the absolute motion of the Pacific plate, we combined two different approaches: the polygonal finite rotation method (PFRM) by Harada and Hamano (2000) and the hot-spotting technique developed by Wessel and Kroenke (1997). The PFRM can determine accurate positions of finite rotation poles for the Pacific plate if the present positions of hotspots are known. On the other hand, the hot-spotting technique can predict present positions of hotspots if the absolute plate motion is given. Therefore we can undertake iterative calculations using the two methods. This hybrid method enables us to determine accurate finite rotation poles for the Pacific plate solely from geometry of Hawaii, Louisville and Easter(Crough)-Line hotspot tracks from around 70 Ma to present. Information of ages can be independently assigned to the model after the poles and rotation angles are determined. We did not detect any inter-hotspot motion from the geometry of these Pacific hotspot tracks using this method. The Ar-Ar ages of Pacific seamounts including new age data of ODP Leg 197 are used to test the newly determined model of the Pacific plate motion. The ages of Hawaii, Louisville, Easter(Crough)-Line, and Cobb hotspot tracks are quite consistent with each other from 70 Ma to

  3. ITRF2014 plate motion model

    Science.gov (United States)

    Altamimi, Zuheir; Métivier, Laurent; Rebischung, Paul; Rouby, Hélène; Collilieux, Xavier

    2017-06-01

    For various geodetic and geophysical applications, users need to have access to a plate motion model (PMM) that is consistent with the ITRF2014 frame. This paper describes the approach used for determining a PMM from the horizontal velocities of a subset of the ITRF2014 sites away from plate boundaries, Glacial Isostatic Adjustment regions and other deforming zones. In theory it would be necessary to include in the inversion model a translational motion vector (called in this paper origin rate bias, ORB) that would represent the relative motion between the ITRF2014 origin (long-term averaged centre of mass of the Earth as sensed by SLR) and the centre of tectonic plate motion. We show that in practice, the magnitude of the estimated ORB is strongly dependent on the selection of ITRF2014 sites used for the PMM adjustment. Its Z-component can in particular range between 0 and more than 1 mm yr-1 depending on the station network used, preventing any geophysical interpretation of the estimated value. Relying on rigorous statistical criteria, the site selection finally adopted for the ITRF2014-PMM adjustment leads to a relatively small ORB (0.30 ± 0.18 mm yr-1 in the Z-component), which is statistically insignificant at the 2-sigma level, but also according to an F-ratio test. Therefore we opted for an ITRF2014-PMM without estimating the ORB, which in turn accommodates geodetic applications that require access to the ITRF2014 frame through pure plate rotation poles.

  4. The PMA Catalogue: 420 million positions and absolute proper motions

    Science.gov (United States)

    Akhmetov, V. S.; Fedorov, P. N.; Velichko, A. B.; Shulga, V. M.

    2017-07-01

    We present a catalogue that contains about 420 million absolute proper motions of stars. It was derived from the combination of positions from Gaia DR1 and 2MASS, with a mean difference of epochs of about 15 yr. Most of the systematic zonal errors inherent in the 2MASS Catalogue were eliminated before deriving the absolute proper motions. The absolute calibration procedure (zero-pointing of the proper motions) was carried out using about 1.6 million positions of extragalactic sources. The mean formal error of the absolute calibration is less than 0.35 mas yr-1. The derived proper motions cover the whole celestial sphere without gaps for a range of stellar magnitudes from 8 to 21 mag. In the sky areas where the extragalactic sources are invisible (the avoidance zone), a dedicated procedure was used that transforms the relative proper motions into absolute ones. The rms error of proper motions depends on stellar magnitude and ranges from 2-5 mas yr-1 for stars with 10 mag < G < 17 mag to 5-10 mas yr-1 for faint ones. The present catalogue contains the Gaia DR1 positions of stars for the J2015 epoch. The system of the PMA proper motions does not depend on the systematic errors of the 2MASS positions, and in the range from 14 to 21 mag represents an independent realization of a quasi-inertial reference frame in the optical and near-infrared wavelength range. The Catalogue also contains stellar magnitudes taken from the Gaia DR1 and 2MASS catalogues. A comparison of the PMA proper motions of stars with similar data from certain recent catalogues has been undertaken.

  5. Early breakup of Gondwana: constraints from global plate motion models

    Science.gov (United States)

    Seton, Maria; Zahirovic, Sabin; Williams, Simon; Whittaker, Joanne; Gibbons, Ana; Muller, Dietmar; Brune, Sascha; Heine, Christian

    2015-04-01

    motions during supercontinent break-up and subsequent dispersal. For example, a global analysis of absolute plate velocities over the past 200 million years shows that plates dominated by continental material and bounded by transforms and mid-ocean ridge segments, as is characteristic of plates involved in Gondwana break-up, have average speeds of ~2.6-2.8 cm/yr RMS. In contrast, oceanic plates surrounded by subduction have average speeds of ~8.5 cm/yr RMS. An exception, however, is the rapid motion of India (~18 cm/yr RMS) in the Paleocene preceding its collision with Eurasia, which suggests that plates with continental and cratonic keels can exhibit short-lived (~10 Myr) accelerations resulting from a combination of plume head arrival effects and other complementary plate boundary forces (i.e., slab pull and ridge push). In another example, our reconstructions illustrate that a spectrum of rifting styles from orthogonal to oblique is present during rifting, rather than dominantly orthogonal as often assumed. Although our approach has so far been limited to one supercontinent cycle, these types of models can be extended to cover the entire Phanerozoic, capturing continental rifting and plate behavior over several supercontinent cycles.

  6. An Alternative Estimate of the Motion of the Capricorn Plate

    Science.gov (United States)

    Burris, S. G.; Gordon, R. G.

    2013-12-01

    Diffuse plate boundaries cover ~15% of Earth's surface and can exceed 1000 km in across-strike width. Deforming oceanic lithosphere in the equatorial Indian Ocean accommodates the motion between the India and Capricorn plates and serves as their mutual diffuse plate boundary. This deforming lithosphere lies between the Central Indian Ridge to the west and the Sumatra trench to the east; the plates diverge to the west of ≈74°E and converge to the east of it. Many data have shown that the pole of rotation between the India and Capricorn plates lies within this diffuse plate boundary [1,2]. Surprisingly, however, the recently estimated angular velocity in the MORVEL global set of angular velocities [3] places this pole of rotation north of prior poles by several degrees, and north of the diffuse plate boundary. The motion between the India and Capricorn plates can only be estimated indirectly by differencing the motion of the India plate relative to the Somalia plate, on the one hand, and the motion of the Capricorn plate relative to Somalia plate, on the other. While the MORVEL India-Somalia angular velocity is similar to prior estimates, the MORVEL Capricorn-Somalia pole of rotation lies northwest of its predecessors. The difference is not caused by new transform azimuth data incorporated into MORVEL or by the new application of a correction to spreading rates for outward displacement. Instead the difference appears to be caused by a few anomalous spreading rates near the northern end of the Capricorn-Somalia plate boundary along the Central Indian Ridge. Rejecting these data leads to consistency with prior results. Implications for the motion of the Capricorn plate relative to Australia will be discussed. [1] DeMets, C., R. G. Gordon, and J.-Y. Royer, 2005. Motion between the Indian, Capricorn, and Somalian plates since 20 Ma: implications for the timing and magnitude of distributed deformation in the equatorial Indian ocean, Geophys. J. Int., 161, 445-468. [2

  7. Changes in Plate Motion During Quaternary and Neogene Time (Invited)

    Science.gov (United States)

    Gordon, R. G.; Demets, C.; Argus, D.; Royer, J.

    2009-12-01

    We review some of the evidence for significant changes in plate motion during the past 25 Ma. We will review plate motions estimated over the past 0.78 to 3.2 Ma in the MORVEL set of relative plate angular velocities [DeMets, Gordon, and Argus, 2009], which are derived mainly from spreading rates from marine magnetic anomalies and from the azimuths of well-surveyed transform faults. We will also review plate relative angular velocities estimated from geodetic data while focusing on the GEODVEL set of relative plate angular velocities [Argus et al. 2009], which is determined from a combination of GPS, VLBI, SLR, and DORIS data. We will compare these two data sets to search for recent statistically significant changes in plate motion and, in some cases, discuss possible causes of these changes. We will also review Neogene changes in plate motion with a focus on the change in plate motion in the Indian and Pacific Oceans at about 6 to 8 Ma ago [e.g., Cande et al. 1995; DeMets, Gordon, and Royer 2005; Merkouriev and DeMets, 2006], which includes the onset of lithospheric folding in the equatorial Indian Ocean.

  8. Pacific plate motion change caused the Hawaiian-Emperor Bend

    NARCIS (Netherlands)

    Torsvik, Trond H.; Doubrovine, Pavel V.; Steinberger, Bernhard; Gaina, Carmen; Spakman, Wim; Domeier, Mathew

    2017-01-01

    A conspicuous 60° bend of the Hawaiian-Emperor Chain in the north-western Pacific Ocean has variously been interpreted as the result of an abrupt Pacific plate motion change in the Eocene (∼47 Ma), a rapid southward drift of the Hawaiian hotspot before the formation of the bend, or a combination of

  9. Plate motions and deformations from geologic and geodetic data

    Science.gov (United States)

    Jordan, T. H.

    1986-06-01

    Research effort on behalf of the Crustal Dynamics Project focused on the development of methodologies suitable for the analysis of space-geodetic data sets for the estimation of crustal motions, in conjunction with results derived from land-based geodetic data, neo-tectonic studies, and other geophysical data. These methodologies were used to provide estimates of both global plate motions and intraplate deformation in the western U.S. Results from the satellite ranging experiment for the rate of change of the baseline length between San Diego and Quincy, California indicated that relative motion between the North American and Pacific plates over the course of the observing period during 1972 to 1982 were consistent with estimates calculated from geologic data averaged over the past few million years. This result, when combined with other kinematic constraints on western U.S. deformation derived from land-based geodesy, neo-tectonic studies, and other geophysical data, places limits on the possible extension of the Basin and Range province, and implies significant deformation is occurring west of the San Andreas fault. A new methodology was developed to analyze vector-position space-geodetic data to provide estimates of relative vector motions of the observing sites. The algorithm is suitable for the reduction of large, inhomogeneous data sets, and takes into account the full position covariances, errors due to poorly resolved Earth orientation parameters and vertical positions, and reduces baises due to inhomogeneous sampling of the data. This methodology was applied to the problem of estimating the rate-scaling parameter of a global plate tectonic model using satellite laser ranging observations over a five-year interval. The results indicate that the mean rate of global plate motions for that interval are consistent with those averaged over several million years, and are not consistent with quiescent or greatly accelerated plate motions. This methodology was also

  10. Motion transitions of falling plates via quasisteady aerodynamics.

    Science.gov (United States)

    Hu, Ruifeng; Wang, Lifeng

    2014-07-01

    In this paper, we study the dynamics of freely falling plates based on the Kirchhoff equation and the quasisteady aerodynamic model. Motion transitions among fluttering, tumbling along a cusp-like trajectory, irregular, and tumbling along a straight trajectory are obtained by solving the dynamical equations. Phase diagrams spanning between the nondimensional moment of inertia and aerodynamic coefficients or aspect ratio are built to identify regimes for these falling styles. We also investigate the stability of fixed points and bifurcation scenarios. It is found that the transitions are all heteroclinic bifurcations and the influence of the fixed-point stability is local.

  11. An Assay in Microtitre Plates for Absolute Abundance of Chicken Interferon Alpha Transcripts

    Directory of Open Access Journals (Sweden)

    Renata Novak Kujundžić

    2010-01-01

    Full Text Available Immunosuppression of commercial chickens is a serious animal health and economic problem in the poultry industry. The major causes of the immunosuppression are viruses that suppress transcription of interferon genes, especially interferon alpha. There is a need for monitoring immunosuppression in commercially bred chickens. For this purpose, the absolute abundance of interferon alpha transcripts can be measured in blood of chickens by a suitable assay. Such an assay was used to estimate abundance of chicken interferon alpha in a sample of splenic cells induced with polyinosinic polycytidylic acid. The abundance measured was 29 ± 2 attomoles/µg total RNA. This assay can be performed in microtitre plates using samples collected from chickens in poultry houses.

  12. Rapid Procedure for Determining Present Plate Motion at Any Point on the Earth's Surface.

    Science.gov (United States)

    Christofferson, Eric

    1986-01-01

    Presents a procedure for calculating the compass direction and velocity of present plate motions at any geographical point of interest. Includes a table of the relative and geographic motion of the 11 largest plates and a flow chart for determining their present motion. Also offers suggestions for classroom instruction. (ML)

  13. Plate motion changes drive Eastern Indian Ocean microcontinent formation

    Science.gov (United States)

    Whittaker, J. M.; Williams, S.; Halpin, J.; Wild, T.; Stilwell, J.; Jourdan, F.; Daczko, N. R.

    2016-12-01

    The roles of plate tectonic or mantle dynamic forces in rupturing continental lithosphere remain controversial. Particularly enigmatic is the rifting of microcontinents from mature continental rifted margin - several well-studied microcontinent calving events coincide in space and time with mantle plume activity, but the significance of plumes in driving microcontinent formation remains controversial, and a role for plate-driven processes has also been suggested. In 2011, our team discovered two new microcontinents in the eastern Indian Ocean, the Batavia and Gulden Draak microcontinents. These microcontinents are unique as they are the only surviving remnants of the now-destroyed or highly deformed Greater Indian margin and provide us with an opportunity to test existing models of microcontinent formation against new observations. Here, we explore models for microcontinent formation using our new data from the Eastern Indian Ocean in a plate tectonic reconstruction framework. We use Argon dating and paleontology results to constrain calving from greater India at 101-104 Ma. This region had been proximal to the active Kerguelen plume for 30 Myrs but we demonstrate that calving did not correspond with a burst of volcanic activity. Rather, it is likely that plume-related thermal weakening of the Indian passive margin preconditioned it for microcontinent formation but calving was triggered by changes in plate tectonic boundary forces. Changes in the relative motions between Indian and Australia led to increasing compressive forces along the long-offset Wallaby-Zenith Fracture Zone, which was eventually abandoned during the jump of the spreading ridge into the Indian continental margin.

  14. Active Deformation in the Overriding Plate Associated with Temporal Changes of the Philippine Sea Plate Motion

    Science.gov (United States)

    Ishiyama, T.; Sato, H.; Van Horne, A.

    2015-12-01

    We present detailed geologic evidence linking changes over time in Philippine Sea plate (PHS) motion and intracontinental deformation in central and southwest (SW) Japan during the Pliocene and after. In the early Pliocene, subduction of the PHS plate under SW Japan restarted in a northerly direction after period of deceleration or cessation. Later, motion changed to a more westerly direction. Corresponding geological changes found in the overriding plate include unconformities in the forearc basins, changes in slip sense on faults, depocenter migration, re-organization of drainage systems and volcanism. Quaternary intraplate deformation is prominent north of the Median Tectonic Line (MTL) inactive segment, above a shallow flat slab. In contrast, less Quaternary tectonic activity is found north of the MTL active segment which lies over a steadily-slipping portion of the subducting slab that behaves as a less-deformed rigid block. Depocenters and active thrusting have migrated north/northwestward over the past 5 My above the shallow flat slab segment of the PHS. We reconstructed the Plio-Pleistocene migration history using Neogene stratigraphy and shallow seismic reflection profiles. We see shallow PHS slab contact with the lower continental crust in our deep seismic reflection profiles, which may explain its enhanced downward drag of the overriding plate and synchronous strong compression in the crust. We find evidence of more westerly PHS plate subduction since the middle Pleistocene in (1) unconformities in the Kumano forearc basin deposits in SW Japan, (2) drastic stream captures in Shikoku, and (3) concordant changes in fault slip sense from thrust to dextral slip along the MTL. Oblique subduction could have induced stronger horizontal stress in the overriding plate above the shallow flat slab which could account for the increasing geologic slip rate observed on active structures. During four repetitions of megathrust earthquake sequences since the 17th century

  15. Absolute Calibration of Image Plate for electrons at energy between 100 keV and 4 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H; Back, N L; Eder, D C; Ping, Y; Song, P M; Throop, A

    2007-12-10

    The authors measured the absolute response of image plate (Fuji BAS SR2040) for electrons at energies between 100 keV to 4 MeV using an electron spectrometer. The electron source was produced from a short pulse laser irradiated on the solid density targets. This paper presents the calibration results of image plate Photon Stimulated Luminescence PSL per electrons at this energy range. The Monte Carlo radiation transport code MCNPX results are also presented for three representative incident angles onto the image plates and corresponding electron energies depositions at these angles. These provide a complete set of tools that allows extraction of the absolute calibration to other spectrometer setting at this electron energy range.

  16. The HST Large Programme on ω Centauri. III. Absolute Proper Motion

    Science.gov (United States)

    Libralato, Mattia; Bellini, Andrea; Bedin, Luigi R.; Moreno D., Edmundo; Fernández-Trincado, José G.; Pichardo, Barbara; van der Marel, Roeland P.; Anderson, Jay; Apai, Dániel; Burgasser, Adam J.; Fabiola Marino, Anna; Milone, Antonino P.; Rees, Jon M.; Watkins, Laura L.

    2018-02-01

    In this paper, we report a new estimate of the absolute proper motion (PM) of the globular cluster NGC 5139 (ω Cen) as part of the HST large program GO-14118+14662. We analyzed a field 17 arcmin southwest of the center of ω Cen and computed PMs with epoch spans of ∼15.1 years. We employed 45 background galaxies to link our relative PMs to an absolute reference-frame system. The absolute PM of the cluster in our field is ({μ }α \\cos δ ,{μ }δ )=(-3.341+/- 0.028,-6.557+/- 0.043) mas yr‑1. Upon correction for the effects of viewing perspective and the known cluster rotation, this implies that for the cluster center of mass ({μ }α \\cos δ ,{μ }δ )=(-3.238+/- 0.028,-6.716+/- 0.043) mas yr‑1. This measurement is direct and independent, has the highest random and systematic accuracy to date, and will provide an external verification for the upcoming Gaia Data Release 2. It also differs from most reported PMs for ω Cen in the literature by more than 5σ, but consistency checks compared to other recent catalogs yield excellent agreement. We computed the corresponding Galactocentric velocity, calculated the implied orbit of ω Cen in two different Galactic potentials, and compared these orbits to the orbits implied by one of the PM measurements available in the literature. We find a larger (by about 500 pc) perigalactic distance for ω Cen with our new PM measurement, suggesting a larger survival expectancy for the cluster in the Galaxy.

  17. Sensitivity analysis of the GNSS derived Victoria plate motion

    Science.gov (United States)

    Apolinário, João; Fernandes, Rui; Bos, Machiel

    2014-05-01

    Fernandes et al. (2013) estimated the angular velocity of the Victoria tectonic block from geodetic data (GNSS derived velocities) only.. GNSS observations are sparse in this region and it is therefore of the utmost importance to use the available data (5 sites) in the most optimal way. Unfortunately, the existing time-series were/are affected by missing data and offsets. In addition, some time-series were close to the considered minimal threshold value to compute one reliable velocity solution: 2.5-3.0 years. In this research, we focus on the sensitivity of the derived angular velocity to changes in the data (longer data-span for some stations) by extending the used data-span: Fernandes et al. (2013) used data until September 2011. We also investigate the effect of adding other stations to the solution, which is now possible since more stations became available in the region. In addition, we study if the conventional power-law plus white noise model is indeed the best stochastic model. In this respect, we apply different noise models using HECTOR (Bos et al. (2013), which can use different noise models and estimate offsets and seasonal signals simultaneously. The seasonal signal estimation is also other important parameter, since the time-series are rather short or have large data spans at some stations, which implies that the seasonal signals still can have some effect on the estimated trends as shown by Blewitt and Lavellee (2002) and Bos et al. (2010). We also quantify the magnitude of such differences in the estimation of the secular velocity and their effect in the derived angular velocity. Concerning the offsets, we investigate how they can, detected and undetected, influence the estimated plate motion. The time of offsets has been determined by visual inspection of the time-series. The influence of undetected offsets has been done by adding small synthetic random walk signals that are too small to be detected visually but might have an effect on the

  18. The difference between the perception of absolute and relative motion: A reaction time study

    NARCIS (Netherlands)

    J.B.J. Smeets (Jeroen); E. Brenner (Eli)

    1994-01-01

    textabstractWe used a reaction-time paradigm to examine the extent to which motion detection depends on relative motion. In the absence of relative motion, the responses could be described by a simple model based on the detection of a fixed change in position. If relative motion was present, the

  19. A New Light-Speed Anisotropy Experiment: Absolute Motion and Gravitational Waves Detected

    Directory of Open Access Journals (Sweden)

    Cahill R. T.

    2006-10-01

    Full Text Available Data from a new experiment measuring the anisotropy of the one-way speed of EM waves in a coaxial cable, gives the speed of light as 300,000 +/- 400 (+/- 20 km/s in a measured direction RA=5.5 +/- 2 hrs, Dec=70 +/- 10 Deg S, is shown to be in excellent agreement with the results from seven previous anisotropy experiments, particularly those of Miller (1925/26, and even those of Michelson and Morley (1887. The Miller gas-mode interferometer results, and those from the RF coaxial cable experiments of Torr and Kolen (1983, De Witte (1991 and the new experiment all reveal the presence of gravitational waves, as indicated by the last +/- variations above, but of a kind different from those supposedly predicted by General Relativity. Miller repeated the Michelson-Morley 1887 gas-mode interferometer experiment and againdetected the anisotropy of the speed of light, primarily in the years 1925/1926 atop Mt.Wilson, California. The understanding of the operation of the Michelson interferometer in gas-mode was only achieved in 2002 and involved a calibration for the interferometer that necessarily involved Special Relativity effects and the refractive index of the gas in the light paths. The results demonstrate the reality of the Fitzgerald-Lorentz contraction as an observer independent relativistic effect. A common misunderstanding is that the anisotropy of the speed of light is necessarily in conflict with Special Relativity and Lorentz symmetry - this is explained. All eight experiments and theory show that we have both anisotropy of the speed of light and relativistic effects, and that a dynamical 3-space exists - that absolute motion through that space has been repeatedly observed since 1887. These developments completely change fundamental physics and our understanding of reality. Modern vacuum-mode Michelson interferometers, particularly the long baseline terrestrial versions, are, by design flaw, incapable of detecting the anisotropy effect and the

  20. Contemporary plate motions from Lageos - A decade later

    Science.gov (United States)

    Christodoulidis, D. C.; Smith, D. E.; Klosko, S. M.; Dunn, P. J.; Robbins, J. W.

    1986-01-01

    Progress made due to Lageos tracking and the participation of over 20 countries in the acquisition and analysis of precise range measurements is reviewed. Results of both the observed global and regional plate kinematics are presented. Mission accomplishments include the following: (1) laser technology advancements of more than an order of magnitude in single point range precision over the last ten years, (2) station positioning at the few centimeter accuracy level for annual solutions, and (3) the emergence of a global picture of plate kinematics.

  1. Australian plate motion and topography linked to fossil New Guinea slab below Lake Eyre

    NARCIS (Netherlands)

    Schellart, W. P.; Spakman, W.

    2015-01-01

    Unravelling causes for absolute plate velocity change and continental dynamic topography change is challenging because of the interdependence of large-scale geodynamic driving processes. Here, we unravel a clear spatio-temporal relation between latest Cretaceous-Early Cenozoic subduction at the

  2. 2D Traveling Wave Driven Piezoelectric Plate Robot for Planar Motion

    OpenAIRE

    Hariri , Hassan; Bernard , Yves; Razek , Adel

    2018-01-01

    International audience; —In this paper, a concept design of a novel Traveling Wave Driven Piezoelectric Plate Robot (TWDPPR) for planar motion is presented. The TWDPPR consists of an aluminium plate structure, with four non-collocated piezoelectric patches bonded on its surface. A two dimensions modeling of non-collocated piezoelectric patches bonded on thin structures developed and validated in previous work is used in this paper to model the TWDPPR based on the " two modes excitation " meth...

  3. Motion of a thin elliptic plate under symmetric and asymmetric orthotropic friction forces

    Science.gov (United States)

    Silantyeva, O.; Dmitriev, N.

    2018-03-01

    The anisotropy of a friction force is proved to be an important factor in various contact problems. We study the dynamical behavior of thin plates with respect to symmetric and asymmetric orthotropic friction. The terminal motion of plates with circular and elliptic contact areas is analyzed. The evaluation of friction forces for both symmetric and asymmetric orthotropic cases is shown using an analytic approach. Regular pressure distribution is considered. Differential equations are formulated and solved numerically for a number of initial conditions. The method used gives more accurate results compared to the previous study. Examples show the significant influence of friction force asymmetry on motion.

  4. Determination of Proper Motions of Circumpolar Stars by Using Images from Ukrvo Plate Archives

    Science.gov (United States)

    Protsyuk, Yu.; Andruk, V.; Mazhaev, A.; Kovylianska, O.; Protsyuk, S.; Golovnya, V.

    UkrVO plate archives contain informationobtained at different time periods and in different observatories for the same regions of the sky [3, 5, 6, 7, 8]. It allows us to carry out joint processing of plates and to receive new results for interesting objects. To obtain proper motions of stars in circumpolar areas, we selected 34 photographic plates from the RI NAO archive and 161 plates from the archive of the MAO NAS. A mean epoch difference between the plates from these archives is 55 years. Scanning of the plates and data processing were independently carried out by both observatories. A catalog of equatorial positions for 195 thousand stars up to 15m was compiled in the RI NAO (black dots in Fig. 1). A catalog of equatorial positions for 1050 thousand stars up to 16.5m was compiled in MAO (gray dots in Fig. 1). A comparison of positions for common stars contained in these catalogs was conducted. A catalog of proper motions for 30 thousand common stars up to 15m was compiled using these two input catalogs. The obtained result suggests the advisability of processing of all observations to receive proper motions of stars up to 14-15m in the declination zone of 65° to 90°.

  5. Anomalous Late Jurassic motion of the Pacific Plate with implications for true polar wander

    Science.gov (United States)

    Fu, R. R.; Kent, D.

    2017-12-01

    True polar wander, or TPW, is the rotation of the entire mantle-crust system that results in simultaneous change in latitude and orientation for all lithospheric plates. One of the most recent candidate TPW events consists of a 30˚ rotation during Late Jurassic time (160 - 145 Ma). However, existing paleomagnetic documentation of this event derives exclusively from continental studies. Because all major landmasses except China were connected directly or via spreading centers in the Late Jurassic, the velocities of these continents were mutually constrained and their motion as a group over the underlying mantle would be indistinguishable from TPW using only continental data. On the other hand, plates of the Pacific Basin constituted a kinematically independent domain, interfacing with continents at subduction zones and slip-strike boundaries. Coherent motion of both Pacific Basin and continental plates would therefore indicate uniform motion of virtually the entire lithosphere, providing a means to distinguish TPW from continental drift. We performed thermal demagnetization on remaining samples from Ocean Drilling Program (ODP) Site 801B, which were cored from the oldest sampled oceanic crust in the Western Pacific, to determine its change in paleolatitude during the Late Jurassic and Early Cretaceous (167 - 134 Ma). We find that the Pacific Plate likely underwent a steady southward drift during this time period, consistent with previous results from magnetic anomalies, except for an episode of northward motion between Oxfordian and Tithonian time (161 - 147 Ma). Although the amplitude of this northward shift is subject to significant uncertainty due to the sparse recovery of core samples, the trajectory of the Pacific Plate is most simply explained by TPW in the 160 - 145 Ma interval as inferred from continental data. Furthermore, such an interpretation is consistent with the sense of shear inferred at the Farallon-North American Plate boundary, whereas uniform

  6. Impact of uncertain reference-frame motions in plate kinematic reconstructions

    DEFF Research Database (Denmark)

    Iaffaldano, Giampiero; Stein, Seth

    2017-01-01

    Geoscientists infer past plate motions, which serve as fundamental constraints for a range of studies, from observations of magnetic isochrons as well as hotspots tracks on the ocean floor and, for stages older than the Cretaceous, from paleomagnetic data. These observations effectively represent...

  7. Past plate and mantle motion from new ages for the Hawaiian-Emperor Seamount Chain

    Science.gov (United States)

    O'Connor, John; Steinberger, Bernhard; Regelous, Marcel; Koppers, Anthony; Wijbrans, Jan; Haase, Karsten; Stoffers, Peter; Jokat, Wilfried; Garbe-Schoenberg, C.-Dieter

    2014-05-01

    Estimates of the relative motion between the Hawaiian and Louisville hotspots have consequences for understanding the role and character of deep Pacific-mantle return flow. The relative motion between these primary hotspots can be inferred by comparing the age records for their seamount trails. Our new 40Ar/39Ar ages for 18 lavas from 10 seamounts along the Hawaiian-Emperor Seamount Chain (HESC) show that volcanism started in the sharp portion of the Hawaiian-Emperor Bend (HEB) at ≥47.5 Ma and continued for ≥5 Myr (O'Connor et al., 2013). The slope of the along-track distance from the currently active Hawaiian hotspot plotted versus age is remarkably linear between ~57 and 25 Ma in the central ˜1900 km of the seamount chain, including the HEB. This model predicts an age for the oldest Emperor Seamounts that matches published ages, implying that a linear age-distance relationship might extend back to at least 82 Ma. In contrast, Hawaiian age progression was much faster since at least ~15 Ma and possibly as early as ~27 Ma. Linear age-distance relations for the Hawaii-Emperor and Louisville seamount chains predict ~300 km overall hotspot relative motion between 80 and 47.5 Ma, in broad agreement with numerical models of plumes in a convecting mantle, and paleomagnetic data. We show that a change in hotspot relative motion may also have occurred between ~55 Ma and ~50 Ma. We interpret this change in hotspot motion as evidence that the HEB reflects a combination of hotspot and plate motion changes driven by the same plate/mantle reorganization. O'Connor et al. (2013), Constraints on past plate and mantle motion from new ages for the Hawaiian-Emperor Seamount Chain, Geochem. Geophys. Geosyst., 14, 4564-4584, doi:10.1002/ggge.20267.

  8. Comparing the role of absolute sea-level rise and vertical tectonic motions in coastal flooding, Torres Islands (Vanuatu).

    Science.gov (United States)

    Ballu, Valérie; Bouin, Marie-Noëlle; Siméoni, Patricia; Crawford, Wayne C; Calmant, Stephane; Boré, Jean-Michel; Kanas, Tony; Pelletier, Bernard

    2011-08-09

    Since the late 1990s, rising sea levels around the Torres Islands (north Vanuatu, southwest Pacific) have caused strong local and international concern. In 2002-2004, a village was displaced due to increasing sea incursions, and in 2005 a United Nations Environment Programme press release referred to the displaced village as perhaps the world's first climate change "refugees." We show here that vertical motions of the Torres Islands themselves dominate the apparent sea-level rise observed on the islands. From 1997 to 2009, the absolute sea level rose by 150 + /-20 mm. But GPS data reveal that the islands subsided by 117 + /-30 mm over the same time period, almost doubling the apparent gradual sea-level rise. Moreover, large earthquakes that occurred just before and after this period caused several hundreds of mm of sudden vertical motion, generating larger apparent sea-level changes than those observed during the entire intervening period. Our results show that vertical ground motions must be accounted for when evaluating sea-level change hazards in active tectonic regions. These data are needed to help communities and governments understand environmental changes and make the best decisions for their future.

  9. A new GPS velocity field for the Pacific Plate - Part 1: constraints on plate motion, intraplate deformation, and the viscosity of Pacific basin asthenosphere

    Science.gov (United States)

    DeMets, C.; Márquez-Azúa, Bertha; Cabral-Cano, Enrique

    2014-12-01

    We combine new, well-determined GPS velocities from Clarion, Guadalupe and Socorro islands on young seafloor in the eastern Pacific basin with newly estimated velocities for 26 GPS sites from older seafloor in the central, western and southern parts of the Pacific Plate to test for deformation within the interior of the Pacific Plate and estimate the viscosity of the asthenosphere below the plate. Relative to a Pacific Plate reference frame defined from the velocities of the 26 GPS sites in other areas of the Pacific Plate, GPS sites on Clarion and Guadalupe islands in the eastern Pacific move 1.2 ± 0.6 mm yr-1 (1σ) towards S09°W ± 38° and 1.9 ± 0.3 mm yr-1 towards S19°E ± 10°, respectively. The two velocities, which are consistent within their 95 per cent uncertainties, both differ significantly from Pacific Plate motion. Transient volcanic deformation related to a 1993-1996 eruption of the Socorro Island shield volcano renders our GPS velocity from that island unreliable for the tectonic analysis although its motion is also southward like those of Clarion and Guadalupe islands. We test but reject the possibilities that drift of Earth's origin in ITRF2008 or unmodelled elastic offsets due to large-magnitude earthquakes around the Pacific rim since 1993 can be invoked to explain the apparent slow southward motions of Clarion and Guadalupe islands. Similarly, corrections to the Pacific Plate GPS velocity field for possible viscoelastic deformation triggered by large-magnitude earthquakes since 1950 also fail to explain the southward motions of the two islands. Viscoelastic models with prescribed asthenospheric viscosities lower than 1 × 1019 Pa s instead introduce statistically significant inconsistencies into the Pacific Plate velocity field, suggesting that the viscosity of the asthenosphere below the plate is higher than 1 × 1019 Pa s. Elastic deformation from locked Pacific-North America Plate boundary faults is also too small to explain the southward

  10. The benefits of extended plate motion history in mantle circulation models

    Science.gov (United States)

    Webb, Peter; Davies, Huw; Davies, Rhodri; Hochard, Cyril; Stampfli, Gerard

    2010-05-01

    Mantle Circulation Models (MCMs) are mantle convection simulations conditioned with plate motion history. Due to difficulties in reconstructing plate motions beyond ≈ 120 Ma, MCMs often only incorporate the most recent 120 Myr of plate tectonic evolution. We find that such models are strongly influenced by initial conditions. The development of a new series of tectonic reconstructions extending back to the Triassic (230 Ma) and including careful reconstruction of the oceanic parts of the plates (modified from Stampfli and Borel, 2004, Stampfli et al. 2008 and references therein) should prove to be of huge importance to MCMs. In this study we present a comparison between the traditionally used 120 Myr and the latest 230 Myr plate motion histories. We use the three-dimensional spherical mantle convection code TERRA (Bunge et al., 2003) to simulate convection at Earth like vigour. Here we apply the plate motion history as a surface velocity boundary condition to drive the internal convection of an already well-mixed system. The forward models from a chosen starting point to present day yield information on mantle temperature (as well as pressure, velocity and material properties) throughout the volume. One of the ways to validate our results is to compare these with tomographic models. Seismic tomography provides us with a snapshot of Earth's mantle at present day. Assuming that the mantle is driven largely by thermal convection, we can assume that the seismically fast regions are associated with cooler, denser material. The most significant of these can be interpreted as remnants of subducted slabs (Hafkenscheid et al 2006, van der Meer et al. 2010). We convert the temperatures predicted by the MCM to seismic velocities using the latest techniques (e.g. Cobden et al., 2008) and compare the calculated velocities to a range of seismic tomography models (both P and S wave). This way we can examine the validity of the surface velocity boundary condition and identify

  11. A revised kinematic model for the relative motion between Pacific oceanic plates and North America since the Late Cretaceous

    Science.gov (United States)

    Doubrovine, Pavel V.; Tarduno, John A.

    2008-12-01

    The convergence between the Pacific, Farallon, and Kula oceanic plates and the North American plate has provided a driving force for tectonic processes that have shaped the western margin of North America. Yet reconstructions of plate motion in the Pacific basin have traditionally relied on the assumption of fixed hot spots. In the last decade, substantial Cretaceous to Paleogene motion between the Pacific and Atlantic hot spots has been recognized, providing motivation to reevaluate the history of relative motion between Pacific oceanic plates and North America by means of plate circuit reconstructions. This paper presents new kinematic models based on two alternative plate circuits linking the Pacific plate to North America since Late Cretaceous time. When compared to models relying on fixity of Pacific and Indo-Atlantic hot spots, our reconstructions suggest that the Pacific-Kula and Pacific-Farallon ridges were ˜600-1000 km closer to the western margin of North America and hence that the Farallon and Kula plates were smaller in Late Cretaceous to middle Eocene time. These findings cast significant doubt on the viability of a configuration of the Farallon-Kula ridge that juxtaposes the Kula plate with the southern part of the paleo-North American margin during this time interval. The results of our new reconstructions also suggest more oblique convergence between the Farallon (or Kula) plate and North America from the Late Cretaceous to the middle Eocene related to the combination of dominantly northwest motion of the Pacific plate and steady southwest motion of North America. This provides an efficient mechanism for the coast-parallel translation of some accreted terranes of North America. It may also explain the structure of geological units in western North America, such as the Central Belt of the Franciscan Complex, which show a dominant coast-parallel fabric formed during an interval coeval with the episode of oblique convergence.

  12. Evolution of the Walvis Ridge-Rio Grande Rise Hot Spot System: Implications for African and South American Plate motions over plumes

    Science.gov (United States)

    O'Connor, John M.; Duncan, Robert A.

    1990-10-01

    Crystallization ages of volcanic rocks, dredged or drilled from the Walvis Ridge (ten sites) and the Rio Grande Rise (one site), have been determined by the 40Ar/39Ar incremental heating technique. The fundamentally age-progressive distribution of these basement ages suggests a common hot spot source for volcanism on the island of Tristan da Cunha, along the Walvis Ridge and Rio Grande Rise, and for the formation of the continental flood basalts located in Namibia (Africa) and Brazil (South America). The Walvis Ridge-Rio Grande Rise volcanic system evolved along a section of the South Atlantic spreading-axis, as the African and South American plates migrated apart, astride, or in close proximity to, an upwelling plume. Reconstructions of the spatial relationship between the spreading-axis, the Tristan hot spot, and the evolving Walvis Ridge-Rio Grande Rise volcanic feature show that, at about 70 Ma, the spreading-axis began to migrate westward, away from the hot spot. The resulting transition to intraplate hot spot volcanism along the Walvis Ridge (and associated termination of Rio Grande Rise formation) also involved a northward migration of previously formed African seafloor over the hot spot. Rotation parameters for African motion over fixed hot spots (i.e., absolute motion) have been recalculated such that the predicted trail of the Tristan hot spot agrees with the distribution of radiometric and fossil basement ages along the Walvis Ridge. African absolute motion has been extended to the South and North American plates, by the addition of relative motion reconstruction poles.

  13. Anomalous Late Jurassic motion of the Pacific Plate with implications for true polar wander

    Science.gov (United States)

    Fu, Roger R.; Kent, Dennis V.

    2018-05-01

    True polar wander, or TPW, is the rotation of the entire mantle-crust system about an equatorial axis that results in a coherent velocity contribution for all lithospheric plates. One of the most recent candidate TPW events consists of a ∼30° rotation during Late Jurassic time (160-145 Ma). However, existing paleomagnetic documentation of this event derives exclusively from continents, which compose less than 50% of the Earth's surface area and may not reflect motion of the entire mantle-crust system. Additional paleopositional information from the Pacific Basin would significantly enhance coverage of the Earth's surface and allow more rigorous testing for the occurrence of TPW. We perform paleomagnetic analyses on core samples from Ocean Drilling Program (ODP) Site 801B, which were taken from the oldest available Pacific crust, to determine its paleolatitude during the Late Jurassic and Early Cretaceous (167-133 Ma). We find that the Pacific Plate underwent a steady southward drift of 0.49°-0.74° My-1 except for an interval between Kimmeridgian and Tithonian time (157-147 Ma), during which it underwent northward motion at 1.45° ± 0.76° My-1 (1σ). This trajectory indicates that the plates of the Pacific Basin participated in the same large-amplitude (∼30°) rotation as continental lithosphere in the 160-145 Ma interval. Such coherent motion of a large majority of the Earth's surface strongly supports the occurrence of TPW, suggesting that a combination of subducting slabs and rising mantle plumes was sufficient to significantly perturb the Earth's inertia tensor in the Late Jurassic.

  14. Environmental dosimetry of radon-222 and daughters: measurement of absolute calibration factors of CR-39 considering the plate-out effects and environmental factors

    International Nuclear Information System (INIS)

    Paulo, S.R. de.

    1991-08-01

    The subject of this work concerns with the measurement of absolute calibration factors for the use of CR-39 as an absolute detector in indoor and daughters monitoring. Up to now the usefulness of calibration factors was restricted to environmental conditions equal (or very close) to those worthing during their determinations. This fact is consequence of the difficulties related to the understanding of the plate-out properties of radon daughters activity in the air. The plate-out effects on radon daughters monitoring performed by SSNTDs are studied. Our experimental results are in agreement with those of other authors about the great sensitivity of CR-39 to the plate-out effects, fact that recommended its use in this work. Being succeeded in the employment of CR-39 as an alpha-spectrometer we concluded that some important information (like the radon daughters deposition rates on the walls of an environment) can be achieved. The knowledge about the behavior of plate-out made possible the determination of the ranges in zenithal angle and energy where CR-39 can detect alpha-particles with efficiency of 100%, at our conditions of track observation. In this way, we obtained calibration factors for CR-39 that are weakly dependent on environmental conditions. We think that these results can contribute to the improvement of RD (Radiation Detector) detection techniques. (author). 159 refs, 106 figs, 05 tabs

  15. Rigidity and definition of Caribbean plate motion from COCONet and campaign GPS observations

    Science.gov (United States)

    Mattioli, G. S.; Miller, J. A.; DeMets, C.; Jansma, P. E.

    2015-12-01

    The kinematic model of the Caribbean plate presented by DeMets et al. (2007) is based on velocities from 6 continuous and 14 campaign GPS sites. COCONet is a multi-hazard GPS-Met observatory, which extends the existing infrastructure of the PBO in North America into the Caribbean basin. In 2010, UNAVCO in collaboration with UCAR, was funded by NSF to design, build, and initially maintain a network of 50 new cGPS/Met sites and include data from another 50 existing sites in the Caribbean region. The COCONet siting plan is for 46 new stations, 21 refurbished stations, and 77 existing stations across 26 nations in the Caribbean region. Data from all COCONet sites flow into the UNAVCO archive and are processed by the PBO analysis centers and are also processed independently by the UTA Geodesy Lab using GIPSY-OASISII (v.6.3) using an APP strategy and final, precise orbits, clocks, and EOP from JPL in the IGS08r frame. We present a refined estimate of Caribbean plate motion by evaluating data from an expanded number of stations with an improved spatial distribution. In order to better constrain the eastern margin of the plate near the Lesser Antilles subduction interface, campaign GPS observations have been collected on the island of Dominica over the last decade. These are combined with additional campaign observations from the western Caribbean, specifically from Honduras and Nicaragua. We have analyzed a total of 117 sites from the Caribbean region, including campaign data and the data from the cGPS stations that comprise COCONet. An updated velocity field for the Caribbean plate is presented and an inversion of the velocities for 24 sites yields a plate angular velocity that differs from previously published models. Our best fitting inversion to GPS velocities from these 24 sites suggests that 2-plate model for the Caribbean is required to fit the GPS observations, which implies that the Caribbean is undergoing modest (1-3 mm/yr) deformation within its interior. Some

  16. Coupling Motion and Energy Harvesting of Two Side-by-Side Flexible Plates in a 3D Uniform Flow

    Directory of Open Access Journals (Sweden)

    Dibo Dong

    2016-05-01

    Full Text Available The fluid-structure interaction problems of two side-by-side flexible plates with a finite aspect ratio in a three-dimensional (3D uniform flow are numerically studied. The plates’ motions are entirely passive under the force of surrounding fluid. By changing the aspect ratio and transverse distance, the coupling motions, drag force and energy capture performance are analyzed. The mechanisms underlying the plates’ motion and flow characteristics are discussed systematically. The adopted algorithm is verified and validated by the simulation of flow past a square flexible plate. The results show that the plate’s passive flapping behavior contains transverse and spanwise deformation, and the flapping amplitude is proportional to the aspect ratio. In the side-by-side configuration, three distinct coupling modes of the plates’ motion are identified, including single-plate mode, symmetrical flapping mode and decoupled mode. The plate with a lower aspect ratio may suffer less drag force and capture less bending energy than in the isolated situation. The optimized selection for obtaining higher energy conversion efficiency is the plate flapping in single-plate mode, especially the plate with a higher aspect ratio. The findings of this work provide several new physical insights into the understanding of fish schooling and are expected to inspire the developments of underwater robots or energy harvesters.

  17. Determination of Absolute Plate Spacing for the Fabry-Perot Subassembly of the Thermosphere Imager for Global Observations

    Data.gov (United States)

    National Aeronautics and Space Administration — We will rad test a commercial Capacitive to Digital Converter for potential use in geostationary orbit, develop an algorithm to determine absolute spacing using a...

  18. High-resolution Neogene reconstructions of Eurasia-North America Plate motion

    Science.gov (United States)

    Merkouriev, S.; DeMets, C.

    2014-07-01

    We estimate Eurasia-North America Plate motion rotations at ˜1-Myr intervals for the past 20 Myr from more than 11 000 crossings of 21 magnetic reversals from Chron 1n (0.78 Ma) to C6no (19.72 Ma) and flow lines digitized from the Charlie Gibbs, Bight and Molloy fracture zones and transform faults. Adjusted for outward displacement, the 21 best-fitting rotations determined from a simultaneous inversion of the numerous kinematic data reconstruct the reversal crossings with weighted root mean square misfits of only 1-2 km and 0.2-7 km for the transform fault and fracture zone crossings. The new rotations clearly define a ˜1000 km southward shift of the rotation pole and 20 per cent slowdown in seafloor spreading rates between 7 and 6 Ma, preceded by apparently steady plate motion from 19.7 to ˜7 Ma. Data for times since C3An.2 (6.7 Ma) are well fit by a stationary pole of rotation and constant rate of angular opening, consistent with steady motion since 6.7 Ma. The southward shift of the rotation pole at 7-6 Ma implies that Eurasia-North America motion in northeastern Asia changed from slowly convergent before 7 Ma to slowly divergent afterward. Crossings of magnetic reversals C1n through C3An.1 (6.0 Ma) are well fit everywhere in the Arctic basin and south to the Azores triple junction, indicating that the Eurasia and North America plates have not deformed along their mutual boundary since at least 6.0 Ma. However, the new rotations systematically overrotate magnetic lineations older than C3An.1 (6.0 Ma) within 200 km of the Azores triple junction and also overrotate lineations older than C5n along the Gakkel Ridge in the Arctic Basin. Barring misidentifications of the magnetic anomalies in those areas, the pattern and magnitude of the systematic misfits imply that slow (˜1 mm yr-1) distributed or microplate deformation occurred in one or both regions.

  19. Pressure-Driven Poiseuille Flow: A Major Component of the Torque-Balance Governing Pacific Plate Motion

    Science.gov (United States)

    Stotz, I. L.; Iaffaldano, G.; Davies, D. R.

    2018-01-01

    The Pacific Plate is thought to be driven mainly by slab pull, associated with subduction along the Aleutians-Japan, Marianas-Izu-Bonin, and Tonga-Kermadec trenches. This implies that viscous flow within the sub-Pacific asthenosphere is mainly generated by overlying plate motion (i.e., Couette flow) and that the associated shear stresses at the lithosphere's base are resisting such motion. Recent studies on glacial isostatic adjustment and lithosphere dynamics provide tighter constraints on the viscosity and thickness of Earth's asthenosphere and, therefore, on the amount of shear stress that asthenosphere and lithosphere mutually exchange, by virtue of Newton's third law of motion. In light of these constraints, the notion that subduction is the main driver of present-day Pacific Plate motion becomes somewhat unviable, as the pulling force that would be required by slabs exceeds the maximum available from their negative buoyancy. Here we use coupled global models of mantle and lithosphere dynamics to show that the sub-Pacific asthenosphere features a significant component of pressure-driven (i.e., Poiseuille) flow and that this has driven at least 50% of the Pacific Plate motion since, at least, 15 Ma. A corollary of our models is that a sublithospheric pressure difference as high as ±50 MPa is required across the Pacific domain.

  20. [Virtual simulation for optimizing the range of motion in hip alloarthroplasty using an adapted thrust-plate prosthesis model].

    Science.gov (United States)

    Jerosch, J; Wetzel, R; Aldinger, G; Weipert, A; Hanusek, S; Filler, T J; Peuker, E T

    2000-07-01

    The purpose of the present study was to increase the free range of motion in conventional trust-plate prosthesis design and to optimize the trust-plate contact as well as the osteointegration area below the trust-plate. For the first part of the study, the two-dimensional geometry of the osteotomy plane was demonstrated in 25 CT-reconstructed femora after performing a virtual cut at a CCD angle of 135 degrees. In the second part, we constructed a prototype of an anatomic adapted trust-plate prosthesis (A-TPP) with an optimized trust-plate and corpus geometry based on the three-dimensional data of three human cadaveric femurs (age 67-75 years). In the final step, we documented the range of motion with computer-aided movement-mapping and compared the conventional TPP with the A-TPP. The results showed a wide variance in osteotomy geometry in the 12 femurs. With the A-TPP, we were able to obtain a much better fit in the trust plate surface. The movement-mapping showed a much higher range of motion in the A-TPP implant. With the A-TPP, the implant surface area for osteointegration could also be significantly increased.

  1. Evidences for recent plume-induced subduction, microplates and localized lateral plate motions on Venus

    Science.gov (United States)

    Davaille, Anne; Smrekar, Suzanne

    2017-04-01

    Using laboratory experiments and theoretical modeling, we recently showed that plumes could induce roll-back subduction around large coronae. When a hot plume rises under a brittle and visco-elasto-plastic skin/lithosphere, the latter undergoes a flexural deformation which puts it under tension. Radial cracks and rifting of the skin then develop, sometimes using pre-existing weaknesses. Plume material upwells through the cracks (because it is more buoyant) and spreads as a axisymmetric gravity current above the broken denser skin. The latter bends and sinks under the combined force of its own weight and that of the plume gravity current. However, due to the brittle character of the upper part of the experimental lithosphere, it cannot deform viscously to accomodate the sinking motions. Instead, the plate continues to tear, as a sheet of paper would do upon intrusion. Several slabs are therefore produced, associated with trenches localized along partial circles on the plume, and strong roll-back is always observed. Depending on the lithospheric strength, roll-back can continue and triggers a complete resurfacing, or it stops when the plume stops spreading. Two types of microplates are also observed. First, the upwelling plume material creates a set of new plates interior to the trench segments. These plates move rapidly and expand through time, but do not subduct.. In a few cases, we also observe additional microplates exterior to the trenches. This happens when the subducting plate contains preexisting heterogeneities (e.g. fractures) and the subducted slab is massive enough for slab pull to become efficient and induce horizontal plate motions. Scalings derived from the experiments suggest that Venus lithosphere is soft enough to undergo such a regime. And indeed, at least two candidates can be identified on Venus, where plume-induced subduction could have operated. (1) Artemis Coronae is the largest (2300 km across) coronae on Venus and is bounded over 270° of

  2. Dynamic Linkages Between the Transition Zone & Surface Plate Motions in 2D Models of Subduction

    Science.gov (United States)

    Arredondo, K.; Billen, M. I.

    2013-12-01

    While slab pull is considered the dominant force controlling plate motion and speed, its magnitude is controlled by slab behavior in the mantle, where tomographic studies show a wide range of possibilities from direct penetration to folding, or stagnation directly above the lower mantle (e.g. Fukao et al., 2009). Geodynamic studies have investigated various parameters, such as plate age and two phase transitions, to recreate observed behavior (e.g. Běhounková and Cízková, 2008). However, past geodynamic models have left out known slab characteristics that may have a large impact on slab behavior and our understanding of subduction processes. Mineral experiments and seismic observations have indicated the existence of additional phase transitions in the mantle transition zone that may produce buoyancy forces large enough to affect the descent of a subducting slab (e.g. Ricard et al., 2005). The current study systematically tests different common assumptions used in geodynamic models: kinematic versus free-slip boundary conditions, the effects of adiabatic heating, viscous dissipation and latent heat, compositional layering and a more complete suite of phase transitions. Final models have a complete energy equation, with eclogite, harzburgite and pyrolite lithosphere compositional layers, and seven composition-dependent phase transitions within the olivine, pyroxene and garnet polymorph minerals. Results show important feedback loops between different assumptions and new behavior from the most complete models. Kinematic models show slab weakening or breaking above the 660 km boundary and between compositional layers. The behavior in dynamic models with a free-moving trench and overriding plate is compared to the more commonly found kinematic models. The new behavior may have important implications for the depth distribution of deep earthquakes within the slab. Though the thermodynamic parameters of certain phase transitions may be uncertain, their presence and

  3. A subduction zone reference frame based on slab geometry and subduction partitioning of plate motion and trench migration

    NARCIS (Netherlands)

    Schellart, W. P.

    2011-01-01

    The geometry of subducted slabs that interact with the transition zone depends critically on the partitioning of the subduction velocity (v S⊥) at the surface into its subducting plate motion component (vSP⊥) and trench migration component (vT⊥). Geodynamic models of progressive subduction

  4. Numerical and Experimental Study of the Rotational Behaviour of Flat Plates Falling Freely with Periodic Oscillating Motion

    DEFF Research Database (Denmark)

    Hærvig, Jakob; Jensen, Anna Lyhne; Pedersen, Marie Cecilie

    2017-01-01

    -dimensional flow with Reynolds number Re ≈ 10,000 and non-dimensional moment of inertia I* = 0.115. To validate the free fall trajectory obtained by computational fluid dynamics, video recordings are used. Based on the validated free fall computational fluid dynamics simulation, the instantaneous fluid forces......When a flat plate falls freely in periodic oscillating motion regime, unsteady fluid forces create additional lift force contributions due to the rotational behaviour. Computational fluid dynamics is used to simulate the free fall behaviour of a flat plate with aspect ratio β = 20 falling in two...... and torques on the plate are obtained. The validated simulations show significant deviations in per-pendicular and tangential force coefficients at the same angle of attack depending on the trajectory history of the plate. At low angles of attack below 5 deg, the tangential force differs significantly...

  5. Constraints on Past Plate and Mantle Motion from New Ages for the Hawaiian-Emperor Seamount Chain

    Science.gov (United States)

    O'Connor, J. M.; Steinberger, B. M.; Regelous, M.; Koppers, A. A.; Wijbrans, J. R.; Haase, K. M.; Stoffers, P.; Jokat, W.; Garbe-Schoenberg, C.

    2013-12-01

    Estimates of the relative motion between the Hawaiian and Louisville hotspots have consequences for understanding the role and character of deep Pacific-mantle return flow. The relative motion between these primary hotspots can be inferred by comparing the age records for their seamount trails. Our new 40Ar/39Ar ages for 18 lavas from 10 seamounts along the Hawaiian-Emperor Seamount Chain (HESC) show that volcanism started in the sharp portion of the Hawaiian-Emperor Bend (HEB) at ≥47.5 Ma and continued for ≥5 Myr (O'Connor et al., 2013). The slope of the along-track distance from the currently active Hawaiian hotspot plotted versus age is remarkably linear between ~57 and 25 Ma in the central ˜1900 km of the seamount chain, including the HEB. This model predicts an age for the oldest Emperor Seamounts that matches published ages, implying that a linear age-distance relationship might extend back to at least 82 Ma. In contrast, Hawaiian age progression was much faster since at least ~15 Ma and possibly as early as ~27 Ma. Linear age-distance relations for the Hawaii-Emperor and Louisville seamount chains predict ~300 km overall hotspot relative motion between 80 and 47.5 Ma, in broad agreement with numerical models of plumes in a convecting mantle, and paleomagnetic data. We show that a change in hotspot relative motion may also have occurred between ~55 Ma and ~50 Ma. We interpret this change in hotspot motion as evidence that the HEB reflects a combination of hotspot and plate motion changes driven by the same plate/mantle reorganization. O'Connor et al. (2013), Constraints on past plate and mantle motion from new ages for the Hawaiian-Emperor Seamount Chain. Geochem. Geophys. Geosyst., in press.

  6. Focusing of relative plate motion at a continental transform fault: Cenozoic dextral displacement >700 km on New Zealand's Alpine Fault, reversing >225 km of Late Cretaceous sinistral motion

    Science.gov (United States)

    Lamb, Simon; Mortimer, Nick; Smith, Euan; Turner, Gillian

    2016-03-01

    The widely accepted ˜450 km Cenozoic dextral strike-slip displacement on New Zealand's Alpine Fault is large for continental strike-slip faults, but it is still less than 60% of the Cenozoic relative plate motion between the Australian and Pacific plates through Zealandia, with the remaining motion assumed to be taken up by rotation and displacement on other faults in a zone up to 300 km wide. We show here that the 450 km total displacement across the Alpine Fault is an artifact of assumptions about the geometry of New Zealand's basement terranes in the Eocene, and the actual Cenozoic dextral displacement across the active trace is greater than 665 km, with more than 700 km (and 94%) of the relative plate motion in the last 25 Ma at an average rate in excess of 28 mm/yr. It reverses more than 225 km (and Zealandia in the Late Cretaceous, when Zealandia lay on the margin of Gondwana, providing a direct constraint on the kinematics of extension between East and West Antarctica at this time.

  7. Understanding plate-motion changes over the past 100 Myr with quantitative models of the coupled lithosphere/mantle system

    Science.gov (United States)

    Stotz, Ingo; Iaffaldano, Giampiero; Rhodri Davies, D.

    2015-04-01

    The volume of geophysical datasets has grown substantially over recent decades. Our knowledge of continental evolution has increased due to advances in interpreting the records of orogeny and sedimentation. Ocean-floor observations now allow one to resolve past plate motions (e.g. in the North Atlantic and Indian Ocean over the past 20 Myr) at temporal resolutions of about 1 Myr. Altogether, these ever-growing datasets allow us to reconstruct the past evolution of Earth's lithospheric plates in greater detail. This is key to unravelling the dynamics of geological processes, because plate motions and their temporal changes are powerful probe into the evolving force balance between shallow- and deep-rooted processes. However, such progress is not yet matched by the ability to quantitatively model past plate-motion changes and, therefore, to test hypotheses on the dominant controls. The main technical challenge is simulating the rheological behaviour of the lithosphere/mantle system, which varies significantly from viscous to brittle. Traditionally computer models for viscous mantle flow on the one hand, and for the motions of the brittle lithosphere on the other hand, have been developed separately. Coupling of these two independent classes of models has been accomplished only for neo-tectonic scenarios, without accounting for the impact of time-evolving mantle-flow (e.g. Iaffaldano and Bunge 2009). However, we have built a coupled model to simulate the lithosphere/mantle system (using SHELLS and TERRA, respectively) through geological time, and to exploit the growing body of geophysical data as a primary constraint on these quantitative models. TERRA is a global spherical finite-element code for mantle convection (e.g. Baumgardner 1985, Bunge et al. 1996, Davies et al. 2013), whilst SHELLS is a thin-sheet finite-element code for lithosphere dynamics (e.g. Bird 1998). Our efforts are focused, in particular, on achieving the technical ability to: (i) simulate the

  8. PLATE

    DEFF Research Database (Denmark)

    Kling, Joyce; Hjulmand, Lise-Lotte

    2008-01-01

    ’s level of English is sufficient for the increasing number of courses offered in English each semester. This paper addresses these concerns and describes a pilot project initiated in 2003 at CBS to gauge the overall English language proficiency of those teaching content courses in English. Through...... the Project in Language Assessment for Teaching in English (PLATE) language professionals from CBS’s Language Center observe teachers and provide feedback using evaluation criteria from the Common European Framework for Reference (CEFR) supplemented by some additional criteria which take the LSP nature...... of academic teaching and lecturing into account....

  9. Post-20 Ma Motion of the Adriatic Plate: New Constraints From Surrounding Orogens and Implications for Crust-Mantle Decoupling

    Science.gov (United States)

    Le Breton, Eline; Handy, Mark R.; Molli, Giancarlo; Ustaszewski, Kamil

    2017-12-01

    A new kinematic reconstruction that incorporates estimates of post-20 Ma shortening and extension in the Apennines, Alps, Dinarides, and Sicily Channel Rift Zone (SCRZ) reveals that the Adriatic microplate (Adria) rotated counterclockwise as it subducted beneath the European Plate to the west and to the east, while indenting the Alps to the north. Minimum and maximum amounts of rotation are derived by using, respectively, estimates of crustal extension along the SCRZ (minimum of 30 km) combined with crustal shortening in the Eastern Alps (minimum of 115 km) and a maximum amount (140 km) of convergence between Adria and Moesia across the southern Dinarides and Carpatho-Balkan orogens. When combined with Neogene convergence in the Western Alps, the best fit of available structural data constrains Adria to have moved 113 km to the NW (azimuth 325°) while rotating 5 ± 3° counterclockwise relative to Europe since 20 Ma. Amounts of plate convergence predicted by our new model exceed Neogene shortening estimates of several tens of kilometers in both the Apennines and Dinarides. We attribute this difference to crust-mantle decoupling (delamination) during rollback in the Apennines and to distributed deformation related to the northward motion of the Dacia Unit between the southern Dinarides and Europe (Moesia). Neogene motion of Adria resulted from a combination of Africa pushing from the south, the Adriatic-Hellenides slab pulling to the northeast, and crustal wedging in the Western Alps, which acted as a pivot and stopped farther northwestward motion of Adria relative to Europe.

  10. What drives microplate motion and deformation in the northeastern Caribbean plate boundary region?

    NARCIS (Netherlands)

    van Benthem, S.A.C.; Govers, R.; Wortel, R.

    2014-01-01

    The north Caribbean plate boundary zone is a broad deformation zone with several fault systems and tectonic blocks that move with different velocities. The indentation by the Bahamas Platform (the “Bahamas Collision”) is generally invoked as a cause of this fragmentation. We propose that a second

  11. Structure design and motion simulation of the pin-cycloid gear planetary reducer with ring-plate-type

    Science.gov (United States)

    Duan, Hongjie; Li, Lijun; Tao, Junyi

    2017-06-01

    The pin-cycloid gear planetary reducer with ring-plate-type is a new type of reducers. It has high transmission ratio range and high efficiency. In this paper the working principle of pin-cycloid gear planetary reducer is discussed, and the structure of the reducer is designed. Especially for the complexity and the difficulty in modelling of the cycloid gear tooth profile, the parametric design module of cycloid gear is developed to solve the cycloid gear modelling problem through the second development of Solid Works. At last, the speed schemes of the input shaft and output shaft of the reducer are obtained by the motion simulation. Through the analysis of the simulation curves, the rationality of the structure design is proved, which provides a theoretical basis for the design and manufacture of the reducer.

  12. Reconstructing mantle heterogeneity with data assimilation based on the back-and-forth nudging method: Implications for mantle-dynamic fitting of past plate motions

    Science.gov (United States)

    Glišović, Petar; Forte, Alessandro

    2016-04-01

    The paleo-distribution of density variations throughout the mantle is unknown. To address this question, we reconstruct 3-D mantle structure over the Cenozoic era using a data assimilation method that implements a new back-and-forth nudging algorithm. For this purpose, we employ convection models for a compressible and self-gravitating mantle that employ 3-D mantle structure derived from joint seismic-geodynamic tomography as a starting condition. These convection models are then integrated backwards in time and are required to match geologic estimates of past plate motions derived from marine magnetic data. Our implementation of the nudging algorithm limits the difference between a reconstruction (backward-in-time solution) and a prediction (forward-in-time solution) on over a sequence of 5-million-year time windows that span the Cenozoic. We find that forward integration of reconstructed mantle heterogeneity that is constrained to match past plate motions delivers relatively poor fits to the seismic-tomographic inference of present-day mantle heterogeneity in the upper mantle. We suggest that uncertainties in the past plate motions, related for example to plate reorganization episodes, could partly contribute to the poor match between predicted and observed present-day heterogeneity. We propose that convection models that allow tectonic plates to evolve freely in accord with the buoyancy forces and rheological structure in the mantle could provide additional constraints on geologic estimates of paleo-configurations of the major tectonic plates.

  13. Motion

    CERN Document Server

    Graybill, George

    2007-01-01

    Take the mystery out of motion. Our resource gives you everything you need to teach young scientists about motion. Students will learn about linear, accelerating, rotating and oscillating motion, and how these relate to everyday life - and even the solar system. Measuring and graphing motion is easy, and the concepts of speed, velocity and acceleration are clearly explained. Reading passages, comprehension questions, color mini posters and lots of hands-on activities all help teach and reinforce key concepts. Vocabulary and language are simplified in our resource to make them accessible to str

  14. Effects of parabolic motion on an isothermal vertical plate with constant mass flux

    Directory of Open Access Journals (Sweden)

    R. Muthucumaraswamy

    2014-12-01

    Full Text Available An analytical study of free convection flow near a parabolic started infinite vertical plate with isothermal in the presence of uniform mass flux was considered. The mathematical model is reduced to a system of linear partial differential equations for the velocity, the concentration and the temperature; the closed form exact solutions were obtained by the Laplace transform technique. The velocity, temperature and concentration profiles for the different parameters as thermal Grashof number Gr, mass Grashof number Gc, Prandtl number Pr, Schmidt number Sc and time t were graphed and the numerical values for the skin friction were as tabulated. It is observed that the velocity is enhanced as the time increased and the velocity is decreased as the Prandtl number increased.

  15. Motion

    CERN Document Server

    Rivera, Andrea

    2017-01-01

    Motion is all around us. Learn how it is used in art, technology, and engineering. Five easy-to-read chapters explain the science behind motion, as well as its real-world applications. Vibrant, full-color photos, bolded glossary words, and a key stats section let readers zoom in even deeper. Aligned to Common Core Standards and correlated to state standards. Abdo Zoom is a division of ABDO.

  16. Global paleo-lithospheric models for geodynamical analysis of plate reconstructions

    Science.gov (United States)

    Quevedo, L.; Morra, G.; Müller, R. D.

    2012-12-01

    We present a general framework to generate time-dependent global subduction history models from kinematic plate reconstructions and explore their associated coupled plate-mantle dynamic behaviour. Slabs are constructed by advecting material into the mantle by prescribing its radial velocity and following the absolute tangential motion of the subducting plate. A simple geodynamic scenario where plates and slabs define isopycnic and isoviscous regions in an homogeneous or layered mantle was explored using the boundary element method-based software BEMEarth. The resulting dynamic behaviour was used to predict the absolute plate motion directions for the present day and a particular mid-cretaceous (125 Ma) kinematic model. We show how the methodology can be used to compare and revise kinematic reconstructions based on their effect on the balance of plate driving forces and the resulting Euler poles of subducting plates. As an example we compare the Farallon plate dynamics at 125 Ma in a global model with two reconstructions in the context of the evolution of the Western North American Cordillera. Our results suggest a method to identify episodes of absolute plate motions that are inconsistent with the expected plate dynamics.

  17. Magma production rate along the Ninetyeast Ridge and its relationship to Indian plate motion and Kerguelen hot spot activity

    Digital Repository Service at National Institute of Oceanography (India)

    Sreejith, K.M.; Krishna, K.S.

    constraints such as change in the plate velocity, thickness and rheology of the lithosphere, and ridge-plume interactions. Plate reconstruction studies suggest that the Indian plate had significant variations in its speed during the Cretaceous - Paleocene... time (Cande and Stegman 2011, van Hinsbergen et al., 2011, Eagles and Wibisono, 2013, Cande and Patriat, 2015). We observe that onset of rapid movement of the Indian plate under influence of the Reunion Plume at 67 Ma coincides with the decreasing...

  18. Segmentation along the Queen Charlotte Fault: The long-lived influence of plate-motion rotation and Explorer Ridge fracture zones

    Science.gov (United States)

    Miller, N. C.; Walton, M. A. L.; Brothers, D. S.; Haeussler, P. J.; Ten Brink, U. S.; Conrad, J. E.; Kluesner, J.; Andrews, B. D.

    2017-12-01

    The Queen Charlotte Fault (QCF) generally tracks the flow line for Pacific/North America (Pa/NA) relative motion since 20 Ma, indicating that the plate boundary localized along an optimally oriented small circle geometry. Rotation in Pa/NA motion at 10—12 Ma caused the QCF south of 53 N to be oblique to plate motion by 10—20. This oblique convergence appears to be accommodated in part by underthrusting of the Pacific Plate beneath Haida Gwaii and in part by slip on faults west of the QCF. On the west side of the QCF, a series of ridges and small basins oriented subparallel to either the QCF or relative plate motion form a 40-km-wide terrace. New high-resolution seismic reflection data image the seaward edge of the ridges as a vertical contact between horizontal or sometimes downwarped deep-sea sediments and west-vergent anticlinal structures within the ridges, supporting earlier interpretations that these ridges have accommodated some component of oblique motion. We argue that the ridges originated as step overs from fracture zones on Explorer Ridge, analogous to the current fault geometry at the southernmost end of the QCF. There, the Revere-Dellwood Fracture Zone (RDFZ) overlaps the QCF for 120 km and connects to the QCF via a more-optimally oriented extensional right step. 3.9—6.4 Mw strike-slip earthquakes along the RDFZ and a lack of contractional seafloor morphologies along the QCF south of the RDFZ-QCF right step suggest that the step over and reactivation along the RDFZ accommodates a majority of plate motion in this region. Kinematic reconstruction of ridges from 54—56 N indicates that they also originated in a similar location, potentially as right steps from either the RDFZ or Sovanco Fracture Zone. Similarly, the RDFZ flow path is coincident with a truncation of seafloor magnetic anomalies and the outer edge of the ridge-bounded terrace, which both parallel the QCF since at least the onset of Explorer Ridge spreading at 8 Ma. The RDFZ-QCF right

  19. Two-dimensional laser servoing for precision motion control of an ODV robotic license plate recognition system

    Science.gov (United States)

    Song, Zhen; Moore, Kevin L.; Chen, YangQuan; Bahl, Vikas

    2003-09-01

    As an outgrowth of series of projects focused on mobility of unmanned ground vehicles (UGV), an omni-directional (ODV), multi-robot, autonomous mobile parking security system has been developed. The system has two types of robots: the low-profile Omni-Directional Inspection System (ODIS), which can be used for under-vehicle inspections, and the mid-sized T4 robot, which serves as a ``marsupial mothership'' for the ODIS vehicles and performs coarse resolution inspection. A key task for the T4 robot is license plate recognition (LPR). For a successful LPR task without compromising the recognition rate, the robot must be able to identify the bumper locations of vehicles in the parking area and then precisely position the LPR camera relative to the bumper. This paper describes a 2D-laser scanner based approach to bumper identification and laser servoing for the T4 robot. The system uses a gimbal-mounted scanning laser. As the T4 robot travels down a row of parking stalls, data is collected from the laser every 100ms. For each parking stall in the range of the laser during the scan, the data is matched to a ``bumper box'' corresponding to where a car bumper is expected, resulting in a point cloud of data corresponding to a vehicle bumper for each stall. Next, recursive line-fitting algorithms are used to determine a line for the data in each stall's ``bumper box.'' The fitting technique uses Hough based transforms, which are robust against segmentation problems and fast enough for real-time line fitting. Once a bumper line is fitted with an acceptable confidence, the bumper location is passed to the T4 motion controller, which moves to position the LPR camera properly relative to the bumper. The paper includes examples and results that show the effectiveness of the technique, including its ability to work in real-time.

  20. Morphology and kinematics of the rifted margin of West Antarctica in relation to separation from Zealandia and Bellingshausen plate motion

    Science.gov (United States)

    Wobbe, F.; Gohl, K.; Chambord, A.; Sutherland, R.

    2012-04-01

    The final breakup of Gondwana occurred during Late Cretaceous time as rifted continental crust of New Zealand separated from West Antarctica. Geophysical data acquired using R/V Polarstern constrain the structure and age of Antarctica's rifted oceanic margin. The Marie Byrd Land sector resembles a typical magma-poor margin with a narrow steep slope and a 145 km wide continent-ocean transition zone (COTZ). Our transect modelled from gravity and seismic reflection data indicates initial continental crust of thickness 24 km that was stretched 90 km. The Bellingshausen sector, east of the Antipodes Fault, is broad and complex with abundant evidence for later volcanism. The COTZ is ~670 km wide and substantial uncertainty remains as to the nature of crust within the COTZ. Extension estimates fall in the range of 106-304 km for this sector. Seafloor magnetic anomalies adjacent to the Marie Byrd Land sector at the longitude of the Pahemo Fracture Zone indicate a full-spreading rate during c33-c31 (80-68 Myr) of 60 mm/yr, increasing to 74 mm/yr at c27 (62 Myr), and then dropping to 22 mm/yr by c22 (50 Myr). Spreading rates were lower to the west. Extrapolation towards the continental margin indicates that initial oceanic crust formation was at ~c34y (84 Myr). The high extension rate of 30-60 mm/yr during the initial margin formation is consistent with the relatively sharp and symmetrical margin morphology, but subsequent motion of the Bellingshausen plate relative to Antarctica was slow and complex, and modified the rift morphology through migrating deformation and volcanic centres to create a broad and complex COTZ.

  1. HEAT AND MASS TRANSFER EFFECTS ON FLOW PAST PARABOLIC STARTING MOTION OF ISOTHERMAL VERTICAL PLATE IN THE PRESENCE OF FIRST ORDER CHEMICAL REACTION

    Directory of Open Access Journals (Sweden)

    R. Muthucumaraswamy

    2013-06-01

    Full Text Available An exact solution of unsteady flow past a parabolic starting motion of the infinite isothermal vertical plate with uniform mass diffusion, in the presence of a homogeneous chemical reaction of the first order, has been studied. The plate temperature and the concentration level near the plate are raised uniformly. The dimensionless governing equations are solved using the Laplace transform technique. The effect of velocity profiles are studied for different physical parameters, such as chemical reaction parameter, thermal Grashof number, mass Grashof number, Schmidt number, and time. It is observed that velocity increases with increasing values of thermal Grashof number or mass Grashof number. The trend is reversed with respect to the chemical reaction parameter.

  2. Absolute Summ

    Science.gov (United States)

    Phillips, Alfred, Jr.

    Summ means the entirety of the multiverse. It seems clear, from the inflation theories of A. Guth and others, that the creation of many universes is plausible. We argue that Absolute cosmological ideas, not unlike those of I. Newton, may be consistent with dynamic multiverse creations. As suggested in W. Heisenberg's uncertainty principle, and with the Anthropic Principle defended by S. Hawking, et al., human consciousness, buttressed by findings of neuroscience, may have to be considered in our models. Predictability, as A. Einstein realized with Invariants and General Relativity, may be required for new ideas to be part of physics. We present here a two postulate model geared to an Absolute Summ. The seedbed of this work is part of Akhnaton's philosophy (see S. Freud, Moses and Monotheism). Most important, however, is that the structure of human consciousness, manifest in Kenya's Rift Valley 200,000 years ago as Homo sapiens, who were the culmination of the six million year co-creation process of Hominins and Nature in Africa, allows us to do the physics that we do. .

  3. Escape of Sierra Nevada-Great Valley Block Motion Contributes to Upper-Plate Contraction Within the Southern Cascadia Margin Near Humboldt Bay, CA.

    Science.gov (United States)

    Williams, T. B.; Kelsey, H. M.; Freymueller, J. T.

    2002-12-01

    Recent GPS-derived site velocities (1993-2002) in northwestern California reveal that an additional mechanism other than subduction is in part accountable for observed upper plate contraction north of the migrating Mendocino triple junction. Sites at and near Cape Mendocino are moving approximately 30 mm/yr and are consistently oriented approximately N 10° W, sub-parallel to the southern Cascadia trench. Sites just north of latitude 40.4° N begin to be oriented east of north, sub-parallel to the Gorda-North America plate convergence direction. The transition from west-of-north to east-of-north site azimuths occurs 20 km north of the Mendocino Fault. The change in site azimuths is abrupt, with an eastward swing of 25°-30° occurring over a distance of approximately 8 km across the Eel River valley. North and east of Cape Mendocino, sites 50-300 km inland have velocities oriented west of north, consistent with the direction of northern Sierra Nevada-Great Valley (SNGV) block and Pacific-North America (P-NA) relative motion. Northern SNGV block motion is 11 mm/yr directed to the northwest. This velocity persists northwestward to within 50 km of the coast at the latitude of Humboldt Bay. Approximately 20 mm/yr of distributed P-NA motion occurs inland of Cape Mendocino across the northern projections of the Ma'acama and Bartlett Springs fault zones, and continues northward into the Humboldt Bay region. The direction of observed SNGV motion is obliquely convergent to the P-NA relative motion direction. The observed convergence between SNGV and the Coast Ranges begins approximately 130 km inland of the coast near Weaverville, CA. We observe 3-6 mm/yr of roughly east-west contraction in that area, which is near the location of the highest topography in the northern Coast Ranges. Near Humboldt Bay, NE-SW convergence of 16+/-2 mm/yr occurs from the coast to approximately 50 km inland. After removing an estimate of the interseismic subduction zone signal from the

  4. A New Global Model Of Plates Motion Over The Mantle For The Last 300MA: Link Between Mantle Structures, Volcanism and Plate Tectonics.

    Science.gov (United States)

    Jean, B.; Sophie, V. D. G.; Greff-Lefftz, M.; Frizon de Lamotte, D.; Lescanne, M.; Leparmentier, F.

    2017-12-01

    We compare several models of hot spot reference frames published in the litterature retracing the kinematics of the lithosphere over the mantle for the last 120Ma. We then propose a new model between 130 and 300Ma, based on the comparison of various surface indicators (geological, thermal data from boreholes and compilation of global surface volcanism), a reassessment of hot spots classification and paleomagnetic data. We discuss the implication of our model on the location and timing of several types of surface volcanism (subductions, intracontinental volcanism, rifting and LIPS, kimberlites) that we link to deep structures interpreted from tomographic images. A clear degree two permanent organization of mantle convection during this period of time is obvious, and the subduction rate appears to be episodic. We finally deduce from our model mantle TPW (True Polar Wander), the shifting of the entire mantle relative to the earth's spin axis over the last 300 million years. The inferred global motion of the mantle deduced occurs around a Euler pole which axis is close to the earth equator but varies significantly in longitude with respect to time showing complex tridimensional mass reorganizations in the mantle, probably linked to both LLSVPs and slabs effect.

  5. GPS-determination of along-strike variation in Cascadia margin kinematics: Implications for relative plate motion, subduction zone coupling, and permanent deformation

    Science.gov (United States)

    Miller, M. Meghan; Johnson, Daniel J.; Rubin, Charles M.; Dragert, Herb; Wang, Kelin; Qamar, Anthony; Goldfinger, Chris

    2001-04-01

    High-precision GPS geodesy in the Pacific Northwest provides the first synoptic view of the along-strike variation in Cascadia margin kinematics. These results constrain interfering deformation fields in a region where typical earthquake recurrence intervals are one or more orders of magnitude longer than the decades-long history of seismic monitoring and where geologic studies are sparse. Interseismic strain accumulation contributes greatly to GPS station velocities along the coast. After correction for a simple elastic dislocation model, important residual motions remain, especially south of the international border. The magnitude of northward forearc motion increases southward from western Washington (3-7 mm/yr) to northern and central Oregon (˜9 mm/yr), consistent with oblique convergence and geologic constraints on permanent deformation. The margin-parallel strain gradient, concentrated in western Washington across the populated Puget Lowlands, compares in magnitude to shortening across the Los Angeles Basin. Thus crustal faulting also contributes to seismic hazard. Farther south in southern Oregon, north-westward velocities reflect the influence of Pacific-North America motion and impingement of the Sierra Nevada block on the Pacific Northwest. In contrast to previous notions, some deformation related to the Eastern California shear zone crosses northernmost California in the vicinity of the Klamath Mountains and feeds out to the Gorda plate margin.

  6. Crustal movement and plate motion as observed by GPS baseline ranging - trial to make teaching materials for middle- and high-school earth science education by teachers

    Science.gov (United States)

    Matsumoto, T.

    2009-12-01

    Japanese government established the system for renewing educational personnel certificates in 2007 and mandated the adoption of it in April 2009 (cf. “2007 White Paper on Education, Culture, Sports, Science and Technology”, available at http://www.mext.go.jp/english/). The new system shows that the valid period for each regular certificate after the renewal system adoption (April 1, 2009) is until the end of the fiscal year after ten years from satisfying the qualifications required for the certificate. Only persons who have attended over 30 hours and passed the examination in the certificate renewal courses before the expiration of the valid period can renew their certificate which is valid for next ten years. The purpose of this system is for teachers to acquire the latest knowledge and skills. Certificate renewal courses authorized by Ministry of Education, Culture, Sports, Science and Technology of Japan are offered by universities. Attendees will choose based on their specialty and awareness of issues from the various courses with education curriculums and. To renew their certificates, they should include (1) items regarding the latest trends and issues in education (12 hours) and (2) items regarding their speciality and other educational enhancement (three 6-hours course: total 18 hours). In 2008, before the adoption, provisional certificate renewal courses were offered for trial by more than 100 universities. The author offered a 6-hour course titled by “Development of teaching materials for school pupils to make understand the dynamic motion of the earth - utilising the results of the GPS ranging”. This course was targeted mainly for science teachers of middle- and high-schools. The goal of this course was for the attendees to understand the role of GPS ranging for the direct observation of the crustal movement and plate motion, and to produce the teaching materials possibly used in the classrooms. The offering of this course is aiming finally at

  7. Jerks as Guiding Influences on the Global Environment: Effects on the Solid Earth, Its Angular Momentum and Lithospheric Plate Motions, the Atmosphere, Weather, and Climate

    Science.gov (United States)

    Quinn, J. M.; Leybourne, B. A.

    2010-12-01

    modulated. These parameters in turn affect the weather and climate (e.g., the Dust Bowl Era, El Ninos, La Ninas, and hurricanes). The stress/strain within the Earth leads to Earth torsion, vibration, and mass redistribution, which leads to tectonic plate motion, seismicity, volcanism, and gravity waves, which drive atmospheric circulation and the teleconnection processes (i.e., a redistribution of magma beneath the plates) via surge tectonics. Various other connections among these processes and parameters will be discussed.

  8. Structure and breakup history of the rifted margin of West Antarctica in relation to Cretaceous separation from Zealandia and Bellingshausen plate motion

    Science.gov (United States)

    Wobbe, F.; Gohl, K.; Chambord, A.; Sutherland, R.

    2012-04-01

    Geophysical data acquired using R/V Polarstern constrain the structure and age of the rifted oceanic margin of West Antarctica. West of the Antipodes Fracture Zone, the 145 km wide continent-ocean transition zone (COTZ) of the Marie Byrd Land sector resembles a typical magma-poor margin. New gravity and seismic reflection data indicates initial continental crust of thickness 24 km, that was stretched 90 km. Farther east, the Bellingshausen sector is broad and complex with abundant evidence for volcanism, the COTZ is ˜670 km wide, and the nature of crust within the COTZ is uncertain. Margin extension is estimated to be 106-304 km in this sector. Seafloor magnetic anomalies adjacent to Marie Byrd Land near the Pahemo Fracture Zone indicate full-spreading rate during c33-c31 (80-68 Myr) of 60 mm yr-1, increasing to 74 mm yr-1 at c27 (62 Myr), and then dropping to 22 mm yr-1 by c22 (50 Myr). Spreading rates were lower to the west. Extrapolation towards the continental margin indicates initial oceanic crust formation at around c34y (84 Myr). Subsequent motion of the Bellingshausen plate relative to Antarctica (84-62 Myr) took place east of the Antipodes Fracture Zone at rates <40 mm yr-1, typically 5-20 mm yr-1. The high extension rate of 30-60 mm yr-1 during initial margin formation is consistent with steep and symmetrical margin morphology, but subsequent motion of the Bellingshausen plate was slow and complex, and modified rift morphology through migrating deformation and volcanic centers to create a broad and complex COTZ.

  9. Plate tectonics drive tropical reef biodiversity dynamics

    Science.gov (United States)

    Leprieur, Fabien; Descombes, Patrice; Gaboriau, Théo; Cowman, Peter F.; Parravicini, Valeriano; Kulbicki, Michel; Melián, Carlos J.; de Santana, Charles N.; Heine, Christian; Mouillot, David; Bellwood, David R.; Pellissier, Loïc

    2016-05-01

    The Cretaceous breakup of Gondwana strongly modified the global distribution of shallow tropical seas reshaping the geographic configuration of marine basins. However, the links between tropical reef availability, plate tectonic processes and marine biodiversity distribution patterns are still unknown. Here, we show that a spatial diversification model constrained by absolute plate motions for the past 140 million years predicts the emergence and movement of diversity hotspots on tropical reefs. The spatial dynamics of tropical reefs explains marine fauna diversification in the Tethyan Ocean during the Cretaceous and early Cenozoic, and identifies an eastward movement of ancestral marine lineages towards the Indo-Australian Archipelago in the Miocene. A mechanistic model based only on habitat-driven diversification and dispersal yields realistic predictions of current biodiversity patterns for both corals and fishes. As in terrestrial systems, we demonstrate that plate tectonics played a major role in driving tropical marine shallow reef biodiversity dynamics.

  10. Engineering applications and analysis of vibratory motion fourth order fluid film over the time dependent heated flat plate

    Science.gov (United States)

    Mohmand, Muhammad Ismail; Mamat, Mustafa Bin; Shah, Qayyum

    2017-07-01

    This article deals with the time dependent analysis of thermally conducting and Magneto-hydrodynamic (MHD) liquid film flow of a fourth order fluid past a vertical and vibratory plate. In this article have been developed for higher order complex nature fluids. The governing-equations have been modeled in the terms of nonlinear partial differential equations with the help of physical boundary circumstances. Two different analytical approaches i.e. Adomian decomposition method (ADM) and the optimal homotopy asymptotic method (OHAM), have been used for discoveryof the series clarification of the problems. Solutions obtained via two diversemethods have been compared using the graphs, tables and found an excellent contract. Variants of the embedded flow parameters in the solution have been analysed through the graphical diagrams.

  11. Absolute Gravimetry in Fennoscandia

    DEFF Research Database (Denmark)

    Pettersen, B. R; TImmen, L.; Gitlein, O.

    away from this central location. An oval shaped zero uplift isoline tracks the general western and northern coastline of Norway and the Kola peninsula. It returns southwest through Russian Karelia and touches the southern tip of Sweden and northern Denmark. The uplift area (as measured by present day...... motions) has its major axis in the direction of southwest to northeast and covers a distance of about 2000 km. Absolute gravimetry was made in Finland and Norway in 1976 with a rise-and fall instrument. A decade later the number of gravity stations was expanded by JILAg-5, in Finland from 1988, in Norway...... acquired by IfE (FG5-220), FGI (FG5-221), and UMB (FG5-226). New absolute gravity stations were established by the national mapping agencies in Denmark, Norway, and Sweden. The total number of prepared sites in Fennoscandia is now about 30. Most of them are co-located with permanent GPS, for many of which...

  12. Bounds on geologically current rates of motion of groups of hotspots.

    Science.gov (United States)

    Wang, C.; Gordon, R. G.; Zhang, T.

    2017-12-01

    It is widely believed that groups of hotspots in different regions of the world are in relative motion at rates of 10 to 30 mm a-1 or more. Here we present a new method for analyzing geologically current motion between groups of hotspots beneath different plates. In an inversion of 56 globally distributed, equally weighted trends of hotspot tracks, the dispersion is dominated by differences in trend between different plates rather than differences within plates. Nonetheless the rate of hotspot motion perpendicular to the direction of absolute plate motion, vperp, differs significantly from zero for only three of ten plates and then by merely 0.3 to 1.4 mm a-1. The global mean upper bound on |vperp| is 3.2 ±2.7 mm a-1. Therefore, groups of hotspots move slowly and can be used to define a global reference frame for plate motions. Further implications for uncertainties in hotspot trends and current plate motion relative to hotspots will be discussed.

  13. Line Heat-Source Guarded Hot Plate

    Data.gov (United States)

    Federal Laboratory Consortium — Description:The 1-meter guarded hot-plate apparatus measures thermal conductivity of building insulation. This facility provides for absolute measurement of thermal...

  14. Global plate boundary evolution and kinematics since the late Paleozoic

    Science.gov (United States)

    Matthews, Kara J.; Maloney, Kayla T.; Zahirovic, Sabin; Williams, Simon E.; Seton, Maria; Müller, R. Dietmar

    2016-11-01

    Many aspects of deep-time Earth System models, including mantle convection, paleoclimatology, paleobiogeography and the deep Earth carbon cycle, require high-resolution plate motion models that include the evolution of the mosaic of plate boundaries through time. We present the first continuous late Paleozoic to present-day global plate model with evolving plate boundaries, building on and extending two previously published models for the late Paleozoic (410-250 Ma) and Mesozoic-Cenozoic (230-0 Ma). We ensure continuity during the 250-230 Ma transition period between the two models, update the absolute reference frame of the Mesozoic-Cenozoic model and add a new Paleozoic reconstruction for the Baltica-derived Alexander Terrane, now accreted to western North America. This 410-0 Ma open access model provides a framework for deep-time whole Earth modelling and acts as a base for future extensions and refinement. We analyse the model in terms of the number of plates, predicted plate size distribution, plate and continental root mean square (RMS) speeds, plate velocities and trench migration through time. Overall model trends share many similarities to those for recent times, which we use as a first order benchmark against which to compare the model and identify targets for future model refinement. Except for during the period 260-160 Ma, the number of plates (16-46) and ratio of "large" plates (≥ 107.5 km2) to smaller plates ( 2.7-6.6) are fairly similar to present-day values (46 and 6.6, respectively), with lower values occurring during late Paleozoic assembly and growth of Pangea. This temporal pattern may also reflect difficulties in reconstructing small, now subducted oceanic plates further back in time, as well as whether a supercontinent is assembling or breaking up. During the 260-160 Ma timeframe the model reaches a minima in the number of plates, in contrast to what we would expect during initial Pangea breakup and thus highlighting the need for refinement

  15. Absolute nuclear material assay

    Science.gov (United States)

    Prasad, Manoj K [Pleasanton, CA; Snyderman, Neal J [Berkeley, CA; Rowland, Mark S [Alamo, CA

    2010-07-13

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  16. Absolute nuclear material assay

    Science.gov (United States)

    Prasad, Manoj K [Pleasanton, CA; Snyderman, Neal J [Berkeley, CA; Rowland, Mark S [Alamo, CA

    2012-05-15

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  17. ABSOLUTE NEUTRINO MASSES

    DEFF Research Database (Denmark)

    Schechter, J.; Shahid, M. N.

    2012-01-01

    We discuss the possibility of using experiments timing the propagation of neutrino beams over large distances to help determine the absolute masses of the three neutrinos.......We discuss the possibility of using experiments timing the propagation of neutrino beams over large distances to help determine the absolute masses of the three neutrinos....

  18. Pacific plate slab pull and intraplate deformation in the early Cenozoic

    Science.gov (United States)

    Butterworth, N. P.; Müller, R. D.; Quevedo, L.; O'Connor, J. M.; Hoernle, K.; Morra, G.

    2014-08-01

    Large tectonic plates are known to be susceptible to internal deformation, leading to a~range of phenomena including intraplate volcanism. However, the space and time dependence of intraplate deformation and its relationship with changing plate boundary configurations, subducting slab geometries, and absolute plate motion is poorly understood. We utilise a buoyancy-driven Stokes flow solver, BEM-Earth, to investigate the contribution of subducting slabs through time on Pacific plate motion and plate-scale deformation, and how this is linked to intraplate volcanism. We produce a series of geodynamic models from 62 to 42 Ma in which the plates are driven by the attached subducting slabs and mantle drag/suction forces. We compare our modelled intraplate deformation history with those types of intraplate volcanism that lack a clear age progression. Our models suggest that changes in Cenozoic subduction zone topology caused intraplate deformation to trigger volcanism along several linear seafloor structures, mostly by reactivation of existing seamount chains, but occasionally creating new volcanic chains on crust weakened by fracture zones and extinct ridges. Around 55 Ma, subduction of the Pacific-Izanagi ridge reconfigured the major tectonic forces acting on the plate by replacing ridge push with slab pull along its northwestern perimeter, causing lithospheric extension along pre-existing weaknesses. Large-scale deformation observed in the models coincides with the seamount chains of Hawaii, Louisville, Tokelau and Gilbert during our modelled time period of 62 to 42 Ma. We suggest that extensional stresses between 72 and 52 Ma are the likely cause of large parts of the formation of the Gilbert chain and that localised extension between 62 and 42 Ma could cause late-stage volcanism along the Musicians volcanic ridges. Our models demonstrate that early Cenozoic changes in Pacific plate driving forces only cause relatively minor changes in Pacific absolute plate motion

  19. Pacific plate slab pull and intraplate deformation in the early Cenozoic

    Directory of Open Access Journals (Sweden)

    N. P. Butterworth

    2014-08-01

    Full Text Available Large tectonic plates are known to be susceptible to internal deformation, leading to a~range of phenomena including intraplate volcanism. However, the space and time dependence of intraplate deformation and its relationship with changing plate boundary configurations, subducting slab geometries, and absolute plate motion is poorly understood. We utilise a buoyancy-driven Stokes flow solver, BEM-Earth, to investigate the contribution of subducting slabs through time on Pacific plate motion and plate-scale deformation, and how this is linked to intraplate volcanism. We produce a series of geodynamic models from 62 to 42 Ma in which the plates are driven by the attached subducting slabs and mantle drag/suction forces. We compare our modelled intraplate deformation history with those types of intraplate volcanism that lack a clear age progression. Our models suggest that changes in Cenozoic subduction zone topology caused intraplate deformation to trigger volcanism along several linear seafloor structures, mostly by reactivation of existing seamount chains, but occasionally creating new volcanic chains on crust weakened by fracture zones and extinct ridges. Around 55 Ma, subduction of the Pacific-Izanagi ridge reconfigured the major tectonic forces acting on the plate by replacing ridge push with slab pull along its northwestern perimeter, causing lithospheric extension along pre-existing weaknesses. Large-scale deformation observed in the models coincides with the seamount chains of Hawaii, Louisville, Tokelau and Gilbert during our modelled time period of 62 to 42 Ma. We suggest that extensional stresses between 72 and 52 Ma are the likely cause of large parts of the formation of the Gilbert chain and that localised extension between 62 and 42 Ma could cause late-stage volcanism along the Musicians volcanic ridges. Our models demonstrate that early Cenozoic changes in Pacific plate driving forces only cause relatively minor changes in Pacific

  20. Absolute local sea surface in the Vanuatu Archipelago from GPS, satellite altimetry and pressure gauge data

    Science.gov (United States)

    Cheng, K. K.; Ballu, V.; Bouin, M.; Calmant, S.; Shum, C.

    2004-12-01

    Water height measurements provided by seafloor tide gauges are a combination of sea level variation and local ground motion. Both signals are of scientific interest, but they must be separated in order to be useful. A reliable estimation of the vertical ground motion is important in very seismically areas such as the Pacific Ocean rim. One promising method to separate the two contributions is to use satellite altimetry which gives absolute water height that is independent of the local ground motion. However, the altimeter data must be calibrated using ground truth measurements. Once different components of the signal are separated, bottom pressure gauges can be used to detect vertical movements of the seafloor. The Vanuatu Archipelago is part of the Pacific "ring of fire", where plates are quickly converging. In this area, movements are very rapid and the seismic activity is intense, which gives a good opportunity to study deformation and seismic cycle. To get an integrate picture of vertical deformation over one plate and between the two plates, one needs to be able to monitor vertical movements on both underwater and emerged areas. We conducted an experiment in this area to compare measurements from bottom pressure gauges located beneath altimetry satellite tracks with sea surface altitude measurements from GPS. Two bottom pressure gauge are immerged since Nov. 1999 in this region. In order to perform absolute calibration for multiple satellite altimeters that overfly the region, we conducted 2 campaigns of GPS measurements of instantaneous sea surface height onboard the R/V Alis and using a GPS buoy. We present results of GPS computations for the March 2003 and March 2004 campaigns. These sea level GPS measurements are compared with multiple altimeter-measured sea surface heights, and sampling differences and high frequency variations were removed using continuous pressure gauge data. The observed discrepancies are likely to be explained by local geoid

  1. Revised Macquarie-Antarctic plate motion during the last 6 Ma using magnetic anomalies of Australian-Antarctic Ridge near 156°-161°E

    Science.gov (United States)

    Choi, H.; Kim, S. S.; Park, S. H.

    2015-12-01

    The longest segment of Australian-Antarctic Ridge (AAR), located near 156°-161°E, is the tectonic boundary between the Australian and the Antarctic plates, and meets the Macquarie Triple Junction of Australian-Antarctic-Pacific plates at the eastern end of the segment. In 2011 and 2013, the multidisciplinary mid-ocean ridge program of Korea Polar Research Institute (KOPRI) conducted a series of geological, geochemical, geophysical, and hydrothermal studies at the segment. Especially, in order to determine the detailed location of the ridge axis, a number of short magnetic cross lines were observed in 2013. In 2015, we additionally collected the magnetic data and the high-resolution shipboard bathymetric data for two 400-km long lines across the ridge segment. Here we utilize the observed magnetic data to estimate spreading rates and its temporal changes along the ridge segment. The half-spreading rates computed using MODMAG with our magnetic data range mostly between 28~34 mm/yr. The southern flank of this ridge segment, which has been added to the Antarctic plate as a trailing side between the Australian and the Antarctic plate, tends to have faster spreading rates compared to the northern flank. According to the previous studies, the Macquarie plate, which is regarded as the intra-plate inside the Australian plate and bounded by the northern flank of the ridge segment in this study, has been rotated relative to the Antarctic plate since about 6 Ma. We revised rotation poles between the Macquarie-Antarctic plates for the chron C2Ay (2.58 Ma), chron C3Ay (6.04 Ma) and the other ages additionally, using Hellinger. In this study, we employed the observed magnetic data with additional constraints from the available shipboard measurements. The synthetic flow-line of Balleny Fracture Zone is used as an input to Hellinger, because the region between the Tasman Fracture Zone and the Macquarie Triple Junction is supposed to be included to the Macquarie plate. We examine

  2. NGS Absolute Gravity Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NGS Absolute Gravity data (78 stations) was received in July 1993. Principal gravity parameters include Gravity Value, Uncertainty, and Vertical Gradient. The...

  3. Decoherence at absolute zero

    OpenAIRE

    Sinha, Supurna

    2005-01-01

    We present an analytical study of the loss of quantum coherence at absolute zero. Our model consists of a harmonic oscillator coupled to an environment of harmonic oscillators at absolute zero. We find that for an Ohmic bath, the offdiagonal elements of the density matrix in the position representation decay as a power law in time at late times. This slow loss of coherence in the quantum domain is qualitatively different from the exponential decay observed in studies of high temperature envir...

  4. Present-day intra-plate deformation of the Eurasian plate

    Science.gov (United States)

    Garcia-Sancho, Candela; Govers, Rob; Warners-Ruckstuhl, Karin N.; Tesauro, Magdala

    2014-05-01

    We build on the results of two recent, yet independent, studies. In the first (Warners-Ruckstuhl et al., 2013) the forces on, and stresses within the Eurasian plate were established. In the second (Tesauro et al., 2012) the distribution of mechanically strong and weak parts of the Eurasian plate was found. The aim of our work is to predict lithospheric deformation of the Eurasian plate and to compare it with observations. This constitutes a test of both the force/stress results and of the strength results. Specific questions are to which extent stresses localize in specific regions and whether micro-plates as identified by geodesists arise naturally from the results. Importantly, Warners-Ruckstuhl et al. (2013) found an ensemble of mechanically consistent force models based on plate interaction forces, lithospheric body forces and convective tractions. Each of these force sets is in mechanical equilibrium. A subset drives Eurasia in the observed direction of absolute motion and generates a stress field in a homogeneous elastic plate that fits observed horizontal stress directions to first order. Deformation models constitute a further test and a possibility to discriminate between the remaining force sets. Following Tesauro et al. (2012) we assume five different compositions for the upper and lower crust. We use their geotherms and crustal thickness maps to estimate vertical distributions of strength at any location within the Eurasian plate. Based on the assumption that horizontal strain rates do not vary with depth allows us to estimate the vertically averaged viscosity of each point. We include major active faults in our mechanical model. We compare our results with GPS velocities, InSAR, seismic, and paleomagnetic observations, which capture present-day and long-term deformation. We discuss various causes for differences.

  5. 40Ar/39Ar geochronology and volume estimates of the Tasmantid Seamounts: Support for a change in the motion of the Australian plate

    Science.gov (United States)

    Crossingham, Tracey J.; Vasconcelos, Paulo M.; Cunningham, Toby; Knesel, Kurt M.

    2017-09-01

    New volume estimates and 40Ar/39Ar ages for the Tasmantid Seamounts are reported to investigate the origin of volcanism and potential links between volcanism and changes in the speed and direction of migration of the Australian plate during the Cenozoic. The results show that the average extrusive volume of individual volcanoes along the seamount chain is 2587 ± 3078 km3 (1 s), and that volumes generally increase towards the south. An exception, the Britannia Guyot, located in the middle of the seamount chain, is the most voluminous (11,374 km3). Nineteen new 40Ar/39Ar ages, from Wreck to Gascoyne, show that the emplacement of the Tasmantid Seamounts occurred between 33.2 ± 1.5 and 6.5 ± 0.6 Ma. A single linear regression applied to the age versus latitude data, assuming volcanism to be caused by plate migration over a stationary hotspot, reveals a plate migration rate of 62 ± 2 kmMa- 1 (R2 = 0.97; n = 27) between 33 and 6 Ma. However, the bend in the seamount track, corresponding with the period of largest eruptive volumes, suggests three distinct segments in the Tasmantid age versus latitude data. The northern segment is consistent with a plate migration rate of 75 ± 10 kmMa- 1 (R2 = 0.88; n = 10) and the southern segment reveals a plate migration rate of 64 ± 4 kmMa- 1 (R2 = 0.94; n = 17). The period between these two segments, from 25 to 19 Ma, overlaps with the period of slow migration and change in the direction of the Australian plate derived from the age versus latitude distribution of continental central volcanoes. The new Tasmantid Seamount results support the interpretation that there were changes in the velocity and direction to Australia's northward trajectory, possibly resulting from a series of collisional events.

  6. Global change and the measurement of absolute sea-level

    Science.gov (United States)

    Diamante, John M.; Pyle, Thomas E.; Carter, William E.; Scherer, Wolfgang

    To quantify properly the long-term response of sea-level to climate change, land motions must be separated from the apparent or relative sea-level change recorded by conventional tide/sea-level gauges. Here we present a concept for global measurement of the true or “absolute” sea-level change, which combines recent advances in space-based geodetic techniques with plans for a global sea-level network under the World Climate Research Programme (WCRP). Data from initial feasibility tests show that land motion, due to global (plate tectonic), regional (glacial rebound), or local (fluid withdrawal) effects, can probably be measured to ±1cm (on a single measurement basis) by an innovative combination of Very Long Baseline Interferometry (VLBI) and Global Positioning System (GPS) tevhniques. By making repeated observations of position at a number of tide gauges using portable, economical GPS receivers in a differential mode relative to the fewer, more stable, but more expensive VLBI observatories, it will be possible to subtract land motion from the relative sea-level signal. Decadal to century scale trends at the 1-2mm y -1 level will be resolvable in the sea-level and vertical land motion time series within about a decade. Detection of subsidence or uplift at specific gauges will allow correction for land motion or deletion of bad data when computing regional or global, i.e. eustatic, sea-level changes. In addition to their applications in oceanography and climate studies, such data will test models by Peltier and other that relate mantle viscosity and deglaciation history to present rates of crustal subsidence or uplift. If the predicted crustal motions are confirmed, we can also have more confidence in the use of historical tide/sea-level gauge records in retrospective studies of sea-level change related to climate variability on decadal or longer time scales. It is concluded that as few as one-third (about 100) of the total number of tide/sea-level gauges (250

  7. Incorporating Cutting Edge Scientific Results from the Margins-Geoprisms Program into the Undergraduate Curriculum, Rupturing Continental Lithosphere Part II: Introducing Euler Poles Using Baja-North America Relative Plate Motion Across the Gulf of California

    Science.gov (United States)

    Loveless, J. P.; Bennett, S. E. K.; Cashman, S. M.; Dorsey, R. J.; Goodliffe, A. M.; Lamb, M. A.

    2014-12-01

    The NSF-MARGINS Program funded a decade of research on continental margin processes. The NSF-GeoPRISMS Mini-lesson Project, funded by NSF-TUES, is designed to integrate the significant findings from the MARGINS program into open-source college-level curriculum. The Gulf of California (GOC) served as the focus site for the Rupturing Continental Lithosphere (RCL) initiative, which addressed several scientific questions: What forces drive rift initiation, localization, propagation and evolution? How does deformation vary in time and space, and why? How does crust evolve, physically and chemically, as rifting proceeds to sea-floor spreading? What is the role of sedimentation and magmatism in continental extension? We developed two weeks of curriculum, including lectures, labs, and in-class activities that can be used as a whole or individually. This component of the curriculum introduces students to the Euler pole description of relative plate motion (RPM) by examining the tectonic interactions of the Baja California microplate and North American plate. The plate boundary varies in rift obliquity along strike, from highly oblique and strike-slip dominated in the south to slightly less oblique and with a larger extensional component in the north. This Google Earth-based exercise provides students with a visualization of RPM using small circle contours of the local direction and magnitude of Baja-North America movement on a spherical Earth. Students use RPM to calculate the fault slip rates on transform, normal, and oblique-slip faults and examine how the varying faulting styles combine to accommodate RPM. MARGINS results are integrated via comparison of rift obliquity with the structural style of rift-related faults around the GOC. We find this exercise to fit naturally into courses about plate tectonics, geophysics, and especially structural geology, given the similarity between Euler pole rotations and stereonet-based rotations of structural data.

  8. Calibration with Absolute Shrinkage

    DEFF Research Database (Denmark)

    Øjelund, Henrik; Madsen, Henrik; Thyregod, Poul

    2001-01-01

    In this paper, penalized regression using the L-1 norm on the estimated parameters is proposed for chemometric je calibration. The algorithm is of the lasso type, introduced by Tibshirani in 1996 as a linear regression method with bound on the absolute length of the parameters, but a modification...

  9. Approach to Absolute Zero

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 6. Approach to Absolute Zero 0.3 K. to a Few Milli-Kelvin. R Srinivasan. Series Article Volume 2 Issue 6 June 1997 pp 6-14. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/002/06/0006-0014 ...

  10. Approach to Absolute Zero

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 2. Approach to Absolute Zero From 4. 22 K. to 0. 3 K. R Srinivasan. Series Article Volume 2 Issue 2 February 1997 pp 8-16. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/002/02/0008-0016 ...

  11. Approach to Absolute Zero

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 10. Approach to Absolute Zero Below 10 milli-Kelvin. R Srinivasan. Series Article Volume 2 Issue 10 October 1997 pp 8-16. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/002/10/0008-0016 ...

  12. Approach to Absolute Zero

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 10. Approach to Absolute Zero Below 10 milli-Kelvin. R Srinivasan. Series Article Volume 2 Issue 10 October 1997 pp 8-16. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/002/10/0008-0016 ...

  13. Absolute Height of Sea Surface by Trajectory of GPS Antennae Over Submerged Pressure Gauges

    Science.gov (United States)

    Bouin, M.; Calmant, S.; Cheng, K.; Ballu, V.; Shum, C. K.; Testut, L.

    2003-12-01

    Water height data provided by seafloor tide gauges is a combination of sea-level variations and ground motion. Both of these signals are of scientific interest, but they must be separated in order to be useful. Estimating ground motion is specially important in very tectonically active areas such as the Pacific Ocean rim. One promising method to separate the two contributions is to use satellite altimetry data which gives absolute water height, but these data must be calibrated using ground truth measurements. Once different components of the signal are separated, bottom pressure gauges can be used to detect vertical movements of the seafloor such as co-seismic or slow inter-seismic motions. The Vanuatu archipelago is part of the Pacific ring of fire, where plates are rapidly converging. In the area, movements are very rapid and the seismic activity is intense, which gives a good opportunity to study deformation and seismic cycle. To get an integrate picture of vertical deformation over one plate and between the two plates, one needs to be able to monitor vertical movements on both underwater and emerged areas. We conducted an experiment in the Vanuatu archipelago, South-West Pacific, to compare measurements from bottom pressure gauges located beneath altimetry satellite tracks with sea surface altitude measurements from GPS. Two bottom pressure gauges are immerged since Nov. 1999 on Sabine bank (15.90° S, 166.14° E) and Wusi Bank (15.34° S, 166.55° E), West of Santo island, Vanuatu. In order to perform absolute calibrations of JASON and ENVISAT altimeters that overfly the Wusi and Sabine banks, respectively, we performed GPS measurements of instantaneous sea surface altitude. The GPS antennae were fixed on top of the 30m long R/V Alis. An inertial unit also recorded the high frequency vessel motions. The height of the antennae over the sea surface was measured using a laser distancemeter in calibration sessions during particularly calm sea states. We present

  14. Calibration with Absolute Shrinkage

    DEFF Research Database (Denmark)

    Øjelund, Henrik; Madsen, Henrik; Thyregod, Poul

    2001-01-01

    In this paper, penalized regression using the L-1 norm on the estimated parameters is proposed for chemometric je calibration. The algorithm is of the lasso type, introduced by Tibshirani in 1996 as a linear regression method with bound on the absolute length of the parameters, but a modification...... to the lasso. The lasso is applied both directly as a calibration method and as a method to select important variables/wave lengths. It is demonstrated that the lasso algorithm, in general, leads to parameter estimates of which some are zero while others are quite large (compared to e.g. the traditional PLS...

  15. The impulsive motion of a flat plate in a viscoelastic fluid in the presence of a transverse magnetic field and porous medium

    International Nuclear Information System (INIS)

    Varshney, A.K.; Varshney, N.K.

    1995-01-01

    In this paper the magnetohydrodynamic (MHD) flow in porous medium near a wall suddenly set in motion has been studied for a particular class of non-Newtonian viscoelastic fluids. For the description of such a fluid one has used the Rivlin-Ericksen constitutive equation, only the first three material constants have been taken into consideration. It is observed that velocity increases with increasing of porosity constant. Due to the presence of elastic property of these elasticoviscous fluids smaller velocities are observed in a thin liquid layer than that for the Newtonian fluids whereas effect of elastic forces beyond this thin liquid layer is just reverse but decreases with the increases of elasticity in the presence of constant magnetic field. (author). 5 refs., 1 fig

  16. Cold plate

    Energy Technology Data Exchange (ETDEWEB)

    Marroquin, Christopher M.; O' Connell, Kevin M.; Schultz, Mark D.; Tian, Shurong

    2018-02-13

    A cold plate, an electronic assembly including a cold plate, and a method for forming a cold plate are provided. The cold plate includes an interface plate and an opposing plate that form a plenum. The cold plate includes a plurality of active areas arranged for alignment over respective heat generating portions of an electronic assembly, and non-active areas between the active areas. A cooling fluid flows through the plenum. The plenum, at the non-active areas, has a reduced width and/or reduced height relative to the plenum at the active areas. The reduced width and/or height of the plenum, and exterior dimensions of cold plate, at the non-active areas allow the non-active areas to flex to accommodate surface variations of the electronics assembly. The reduced width and/or height non-active areas can be specifically shaped to fit between physical features of the electronics assembly.

  17. Plating laboratory

    International Nuclear Information System (INIS)

    Seamster, A.G.; Weitkamp, W.G.

    1984-01-01

    The lead plating of the prototype resonator has been conducted entirely in the plating laboratory at SUNY Stony Brook. Because of the considerable cost and inconvenience in transporting personnel and materials to and from Stony Brook, it is clearly impractical to plate all the resonators there. Furthermore, the high-beta resonator cannot be accommodated at Stony Brook without modifying the set up there. Consequently the authors are constructing a plating lab in-house

  18. Thermodynamics of negative absolute pressures

    International Nuclear Information System (INIS)

    Lukacs, B.; Martinas, K.

    1984-03-01

    The authors show that the possibility of negative absolute pressure can be incorporated into the axiomatic thermodynamics, analogously to the negative absolute temperature. There are examples for such systems (GUT, QCD) processing negative absolute pressure in such domains where it can be expected from thermodynamical considerations. (author)

  19. A new numerical method for investigation of thermophoresis and Brownian motion effects on MHD nanofluid flow and heat transfer between parallel plates partially filled with a porous medium

    Science.gov (United States)

    Sayehvand, Habib-Olah; Basiri Parsa, Amir

    Numerical investigation the problem of nanofluid heat and mass transfer in a channel partially filled with a porous medium in the presence of uniform magnetic field is carried out by a new computational iterative approach known as the spectral local linearization method (SLLM). The similarity solution is used to reduce the governing system of partial differential equations to a set of nonlinear ordinary differential equations which are then solved by SLLM and validity of our solutions is verified by the numerical results (fourth-order Runge-Kutta scheme with the shooting method). In modeling the flow in the channel, the effects of flow inertia, Brinkman friction, nanoparticles concentration and thickness of the porous region are taken into account. The results are obtained for velocity, temperature, concentration, skin friction, Nusselt number and Sherwood number. Also, effects of active parameters such as viscosity parameter, Hartmann number, Darcy number, Prandtl number, Schmidt number, Eckert number, Brownian motion parameter, thermophoresis parameter and the thickness of porous region on the hydrodynamics, heat and mass transfer behaviors are investigated.

  20. A new numerical method for investigation of thermophoresis and Brownian motion effects on MHD nanofluid flow and heat transfer between parallel plates partially filled with a porous medium

    Directory of Open Access Journals (Sweden)

    Habib-Olah Sayehvand

    Full Text Available Numerical investigation the problem of nanofluid heat and mass transfer in a channel partially filled with a porous medium in the presence of uniform magnetic field is carried out by a new computational iterative approach known as the spectral local linearization method (SLLM. The similarity solution is used to reduce the governing system of partial differential equations to a set of nonlinear ordinary differential equations which are then solved by SLLM and validity of our solutions is verified by the numerical results (fourth-order Runge-Kutta scheme with the shooting method. In modeling the flow in the channel, the effects of flow inertia, Brinkman friction, nanoparticles concentration and thickness of the porous region are taken into account. The results are obtained for velocity, temperature, concentration, skin friction, Nusselt number and Sherwood number. Also, effects of active parameters such as viscosity parameter, Hartmann number, Darcy number, Prandtl number, Schmidt number, Eckert number, Brownian motion parameter, thermophoresis parameter and the thickness of porous region on the hydrodynamics, heat and mass transfer behaviors are investigated. Keywords: Brownian, Nanofluid, Porous medium, Spectral local linearization method, Thermophoresis

  1. Static and Monoharmonic Acoustic Impact on a Laminated Plate

    Science.gov (United States)

    Paimushin, V. N.; Gazizullin, R. K.

    2017-07-01

    A discrete layered damping model of a multilayer plate at small displacements and deformations, with account of the internal damping of layers according to the Thompson-Kelvin-Voight model, is presented. Based on the equations derived, an analytical solution to the static deformation problem for single-layer rectangular plate hinge-supported along its contour and subjected of a uniformly distributed pressure applied to one of its boundary planes is obtained. Its convergence to the three-dimensional solution is analyzed in relation to the dimension of mesh in the thickness direction of the plate. It is found that, for thin plates, the dimension of the problem formulated can be reduced on the basis of simplified hypotheses applied to each layer. An analytical solutions is also constructed for the forced vibrations of two- and three-layer rectangular plates hinged in the opening of an absolutely stiff dividing wall upon transmission of a monoharmonic sound wave through them. It was assumed that the dividing wall is situated between two absolutely stiff barriers; one of them, owing to the harmonic vibration with a given displacement amplitude of the plate, forms an incident sound wave, and the other is stationary and is coated by a energy-absorbing material with high damping properties. Behavior of the acoustic media in spaces between the deformable plate and the barriers is described by the classical wave equations based on the model of an ideal compressible fluid. To describe the process of dynamic deformation of the energy-absorbing coating of the fixed barrier, two-dimensional equations of motion are derived based on the model of a transversely soft layer, a linear approximation of displacement fields in the thickness direction of the coating, and the account of damping properties of its material by using the hysteresis model. The effect of physical and mechanical parameters of the mechanical system considered and of frequency of the incident sound wave on the

  2. Absolute risk, absolute risk reduction and relative risk

    Directory of Open Access Journals (Sweden)

    Jose Andres Calvache

    2012-12-01

    Full Text Available This article illustrates the epidemiological concepts of absolute risk, absolute risk reduction and relative risk through a clinical example. In addition, it emphasizes the usefulness of these concepts in clinical practice, clinical research and health decision-making process.

  3. Biomechanical comparison of 4 different lateral plate constructs for distal fibula fractures.

    Science.gov (United States)

    Eckel, Tobin T; Glisson, Richard R; Anand, Prashanth; Parekh, Selene G

    2013-11-01

    Displaced lateral malleolar fractures are often treated with reduction and surgical stabilization. However, there has not been a comprehensive laboratory comparison to determine the most appropriate device for treating these patients. This study subjected a range of contemporary lateral fibular plates to a series of mechanical tests designed to reveal performance differences. Forty fresh frozen lower extremities were divided into 4 groups. A Weber B distal fibula fracture was simulated with an osteotomy and stabilized using 1 of 4 plate systems: a standard Synthes one-third tubular plate with interfragmentary lag screw, a Synthes LCP locking plate with lag screw, an Orthohelix MaxLock Extreme low-profile locking plate with lag screw, or a TriMed Sidewinder nonlocking plate. Controlled monotonic bending and cyclic torsional loading were applied and bending stiffness, torsional stiffness, and fracture site motion were quantified. Resistance to cyclic torsional loading was determined by quantifying the number of loads withstood before excessive rotation occurred. Correlation between bone mineral density and each of the mechanical measures was determined. There was no difference in angulation or bending stiffness between plates. All plates except the LCP showed greater lateral deflection than in the other bending directions. Bending stiffness was lowest in lateral distal fragment deflection for all 4 plates. There was a positive correlation between bone mineral density and bending stiffness for all plate types. There was no difference in fracture site rotation between plate types in internal or external torsion, but internal rotation of the distal fragment consistently exceeded external rotation. Torsional stiffness in external rotation exceeded stiffness in internal rotation in nearly all specimens. LCP plates performed relatively poorly under cyclic torsion. Significant differences in plate performance were not demonstrated. The effects of bone quality variability

  4. Searching for the Lost Jurassic and Cretaceous Ocean Basins of the Circum-Arctic Linking Plate Models and Seismic Tomography

    Science.gov (United States)

    Shephard, G. E.; Müller, R.

    2012-12-01

    The tectonic evolution of the circum-Arctic since the breakup of Pangea involves the opening and closing of ocean basins including the Oimyakon, Angayucham, South Anuyi, Amerasia and Eurasia basins. The time-dependent configurations and kinematic history of the basins, adjacent continental terranes, and subduction zones involved are not well understood, and many published tectonic models for particular regions are inconsistent with models for adjacent areas. The age, location, geometry and convergence rates of the subduction zones associated with these ancient ocean basins since at least the Late Jurassic have implications for mantle structure, which can be used as an additional constraint for building plate and plate boundary models. Here we integrate an analysis of both surface and deep mantle observations back to 200 Ma. Based on a digitized set of tectonic features with time-dependent rotational histories we present a refined plate model with topologically closed plate polygons for the circum-Arctic with particular focus on the northern Pacific, Siberian and Alaskan margins (Fig 1). We correlate the location, geometry and timing of subduction zones with associated seismic velocities anomalies from global P and S wave tomography models across different depths. We design a plate model that best matches slabs imaged in seismic tomography in an iterative fashion. This match depends on a combination of relative and absolute plate motions. Therefore we test two end-member absolute plate motion models, evaluating a paleomagnetic model and a model based on hotspot tracks and large igneous provinces. This method provides a novel approach to deciphering the Arctic tectonic history in a global context. Fig 1:Plate reconstruction at 200Ma and 140Ma, visualized using GPlates software. Present-day topography raster (ETOPO2) segmented into major tectonic elements of the circum-Arctic. Plate boundaries delineated in black and selected subduction and arc features labeled in

  5. Earth's Decelerating Tectonic Plates

    Energy Technology Data Exchange (ETDEWEB)

    Forte, A M; Moucha, R; Rowley, D B; Quere, S; Mitrovica, J X; Simmons, N A; Grand, S P

    2008-08-22

    Space geodetic and oceanic magnetic anomaly constraints on tectonic plate motions are employed to determine a new global map of present-day rates of change of plate velocities. This map shows that Earth's largest plate, the Pacific, is presently decelerating along with several other plates in the Pacific and Indo-Atlantic hemispheres. These plate decelerations contribute to an overall, globally averaged slowdown in tectonic plate speeds. The map of plate decelerations provides new and unique constraints on the dynamics of time-dependent convection in Earth's mantle. We employ a recently developed convection model constrained by seismic, geodynamic and mineral physics data to show that time-dependent changes in mantle buoyancy forces can explain the deceleration of the major plates in the Pacific and Indo-Atlantic hemispheres.

  6. Absolute migration of Pacific basin mid-ocean ridges since 85 Ma ...

    African Journals Online (AJOL)

    Mid-ocean ridges are major physiographic features that dominate the world seafloor. Their absolute motion and tectonics are recorded in magnetic lineations they created. The absolute migration of mid-ocean ridges in the Pacific basin since 85 Ma and their tectonic implications was investigated in this work and the results ...

  7. Indonesian Landforms and Plate Tectonics

    Directory of Open Access Journals (Sweden)

    Herman Th. Verstappen

    2014-06-01

    Full Text Available DOI: 10.17014/ijog.v5i3.103The horizontal configuration and vertical dimension of the landforms occurring in the tectonically unstable parts of Indonesia were resulted in the first place from plate tectonics. Most of them date from the Quaternary and endogenous forces are ongoing. Three major plates – the northward moving Indo-Australian Plate, the south-eastward moving SE-Asian Plate and the westward moving Pacific Plate - meet at a plate triple-junction situated in the south of New Guinea’s Bird’s Head. The narrow North-Moluccan plate is interposed between the Asia and Pacific. It tapers out northward in the Philippine Mobile Belt and is gradually disappearing. The greatest relief amplitudes occur near the plate boundaries: deep ocean trenches are associated with subduction zones and mountain ranges with collision belts. The landforms of the more stable areas of the plates date back to a more remote past and, where emerged, have a more subdued relief that is in the first place related to the resistance of the rocks to humid tropical weathering Rising mountain ranges and emerging island arcs are subjected to rapid humid-tropical river erosions and mass movements. The erosion products accumulate in adjacent sedimentary basins where their increasing weight causes subsidence by gravity and isostatic compensations. Living and raised coral reefs, volcanoes, and fault scarps are important geomorphic indicators of active plate tectonics. Compartmental faults may strongly affect island arcs stretching perpendicular to the plate movement. This is the case on Java. Transcurrent faults and related pull-apart basins are a leading factor where plates meet at an angle, such as on Sumatra. The most complicated situation exists near the triple-junction and in the Moluccas. Modern research methods, such as GPS measurements of plate movements and absolute dating of volcanic outbursts and raised coral reefs are important tools. The mega-landforms resulting

  8. Present-day deformation of the intra-Eurasian plate regions

    Science.gov (United States)

    Garcia Sancho, Candela; Govers, Rob; Tesauro, Magdala

    2015-04-01

    We build on the results of two recent, yet independent, studies. In the first (Warners-Ruckstuhl et al., 2013) the forces on, and stresses within the Eurasian plate were established. In the second (Tesauro et al., 2012) the distribution of mechanically strong and weak parts of the Eurasian plate was found. We predict lithospheric deformation of the Eurasian plate, mainly focused on the Tibetan Plateau and in a lesser scale, on the Zagros Mountains and Anatolia, and compare it with observations. This constitutes a test of both the force/stress results and of the strength results. Specific questions are to which extent stresses localize in specific regions and whether micro-plates as identified by geodesists arise naturally from the results. Importantly, Warners-Ruckstuhl et al. (2013) found an ensemble of mechanically consistent force models based on plate interaction forces, lithospheric body forces and convective tractions. Each of these force sets is in mechanical equilibrium. A subset drives Eurasia in the observed direction of absolute motion and generates a stress field in a homogeneous elastic plate that fits observed horizontal stress directions to first order. Deformation models constitute a further test to discriminate between the remaining force sets. Following Tesauro et al. (2012) we assume five different compositions for the upper and lower crust. We use their geotherms and crustal thickness maps to estimate vertical distributions of strength at any location within the Eurasian plate. From the power-law relationship between strength and viscosity, and based on the assumption that horizontal strain rates do not vary with depth, we estimate the vertically averaged viscosity of each element of the domain. The combination of forces and averaged viscosities, and the inclusion of major active faults in our mechanical model allow us to predict deformation (velocities, strain rates and rotation rates). We compare our results with GPS velocities, InSAR, seismic

  9. Estimates of the Basal-Strength Torques and Tractions That Drive the Plates From Below

    Science.gov (United States)

    Bird, P.; Liu, Z.; Rucker, W. K.

    2008-12-01

    We divide the torques on each surface plate into 3 parts: lithostatic-pressure, side-strength, and basal- strength. (The strength tensor is the stress tensor minus lithostatic pressure.) We compute each part for 52 plates using a thin-shell finite-element model of the lithosphere with: topography, variable heat-flow, variable crust and lithosphere thicknesses from seismic data, transient geotherms, nonlinear rheology, and weak faults. We iterate solutions, adjusting boundary conditions to get correct plate velocities without the need for any model of deep mantle flow. Uncertainty remains because side-strength torques and inferred basal- strength torques depend on the effective friction of faults. Therefore, we compute a suite of models with differing trench resistance and differing fault friction, and evaluate their misfits relative to: seafloor spreading rates, geodetic velocities, intraplate stress directions, and azimuths of seismic anisotropy. The minimum misfit occurs at effective fault friction of 0.1 and trench resistance 2x1012 N/m. Unfortunately, computed values of mean basal-strength traction systematically increase for smaller plates. We analyze error sources and find that the largest is unmodeled variation in effective friction of plate- boundary faults. Discounting highly uncertain results, we find mean basal shear tractions of no more than 1 MPa for the 6 largest slabless plates: AF 0.2 MPa; AN 0.1 MPa; NA 0.6 MPa; EU 1.0 MPa; SA 1.0 MPa; SO 0.9 MPa. The directions of basal shear traction on these plates are generally forward, meaning subparallel to absolute velocity. Basal-strength torques on plates with subducting slabs represent the sum of net slab-pull and distributed basal shear traction; if these torques are attributed to net slab-pull alone, net slab-pull is generally toward the trench and of order 5x1012 N/m. However, our attempts to correlate these inferred net slab- pull values with objective measures like trench depth or plate age have

  10. The Biggest Plates on Earth. Submarine Ring of Fire--Grades 5-6. Plate Tectonics.

    Science.gov (United States)

    National Oceanic and Atmospheric Administration (DOC), Rockville, MD.

    This activity is designed to teach how tectonic plates move, what some consequences of this motion are, and how magnetic anomalies document the motion at spreading centers do. The activity provides learning objectives, a list of needed materials, key vocabulary words, background information, day-to-day procedures, internet connections, career…

  11. Using GPS, tide gauge and altimetry data to constrain subduction parameters at the Vanuatu plate boundary.

    Science.gov (United States)

    Ballu, V.; Bouin, M.; Baillard, C.; Calmant, S.; Pelletier, B.; Crawford, W. C.; Kanas, T.; Garaebiti, E.

    2012-12-01

    The Vanuatu subduction zone, Southwest Pacific, combines several features that makes it a particularly useful place to study seismic cycles. The convergence rate is high - approximately 12 cm/yr - and the seismic cycle relatively short. Measurements of interseismic motions are helped by relatively high vertical rates, the close proximity of some islands to the plate interface and the existence of very shallow seamounts on either side of the plate interface. The Vanuatu archipelago is part of the Pacific Ring of Fire: the Australian plate subducts eastward beneath the North Fiji basin, on the western border of the Pacific Plate. High topographic features on the diving plate may contribute to locking of the plates, which can play a major role in the genesis of destructive earthquakes. GPS network points were installed in the early 1990s and the geodesy network has been densified through the years, enabling us to map interseismic horizontal and vertical deformation rates throughout the archipelago. More recently, 8 continuous GPS stations were installed, along with 3 continuous seafloor pressure gauges very near to the plate interface. We show results from GPS data collected from 1996 to 2011, that we re-processed and combined into the ITRF2008 reference frame, and altimetry and seafloor pressure data from 1999 to 2010. The GPS results show that vertical deformation rates vary both across and along the archipelago. We believe that these variations result from variable distance to the plate limit and variable locking parameters. In some areas, subsidence rates are close to one centimeter per year. In the Torres islands (at the northern end of the archipelago) where villagers face recurrent coastal flooding, we showed that this flooding is due more to ground motion than to rise in the absolute sea level, even though the sea-level rise rates are locally high and the islands uplift over the long term. In the Central area of Vanuatu, we augmented the on-land network with

  12. Motion sickness

    NARCIS (Netherlands)

    Bles, Willem; Bos, Jelte E.; Kruit, Hans

    2000-01-01

    The number of recently published papers on motion sickness may convey the impression that motion sickness is far from being understood. The current review focusses on a concept which tends to unify the different manifestations and theories of motion sickness. The paper highlights the relations

  13. Absolute metrology for space interferometers

    Science.gov (United States)

    Salvadé, Yves; Courteville, Alain; Dändliker, René

    2017-11-01

    The crucial issue of space-based interferometers is the laser interferometric metrology systems to monitor with very high accuracy optical path differences. Although classical high-resolution laser interferometers using a single wavelength are well developed, this type of incremental interferometer has a severe drawback: any interruption of the interferometer signal results in the loss of the zero reference, which requires a new calibration, starting at zero optical path difference. We propose in this paper an absolute metrology system based on multiplewavelength interferometry.

  14. First order sensitivity analysis of flexible multibody systems using absolute nodal coordinate formulation

    International Nuclear Information System (INIS)

    Pi Ting; Zhang Yunqing; Chen Liping

    2012-01-01

    Design sensitivity analysis of flexible multibody systems is important in optimizing the performance of mechanical systems. The choice of coordinates to describe the motion of multibody systems has a great influence on the efficiency and accuracy of both the dynamic and sensitivity analysis. In the flexible multibody system dynamics, both the floating frame of reference formulation (FFRF) and absolute nodal coordinate formulation (ANCF) are frequently utilized to describe flexibility, however, only the former has been used in design sensitivity analysis. In this article, ANCF, which has been recently developed and focuses on modeling of beams and plates in large deformation problems, is extended into design sensitivity analysis of flexible multibody systems. The Motion equations of a constrained flexible multibody system are expressed as a set of index-3 differential algebraic equations (DAEs), in which the element elastic forces are defined using nonlinear strain-displacement relations. Both the direct differentiation method and adjoint variable method are performed to do sensitivity analysis and the related dynamic and sensitivity equations are integrated with HHT-I3 algorithm. In this paper, a new method to deduce system sensitivity equations is proposed. With this approach, the system sensitivity equations are constructed by assembling the element sensitivity equations with the help of invariant matrices, which results in the advantage that the complex symbolic differentiation of the dynamic equations is avoided when the flexible multibody system model is changed. Besides that, the dynamic and sensitivity equations formed with the proposed method can be efficiently integrated using HHT-I3 method, which makes the efficiency of the direct differentiation method comparable to that of the adjoint variable method when the number of design variables is not extremely large. All these improvements greatly enhance the application value of the direct differentiation

  15. Role of the overriding plate in the subduction process: Insights from numerical models

    NARCIS (Netherlands)

    van Dinther, Ylona; Morra, G.; Funiciello, F.; Faccenna, C.

    2010-01-01

    Active convergent margins are primarily shaped by the interplay among the subducting plate, overriding plate, and mantle. The effect of important forces, like far-field mantle flow, overriding plate motion, and inter-plate coupling, however, remains partially ambiguous. In a preliminary attempt to

  16. Absolute pitch--electrophysiological evidence.

    Science.gov (United States)

    Barnea, A; Granot, R; Pratt, H

    1994-02-01

    People who have the ability to label or to produce notes without any reference are considered to possess Absolute Pitch (AP). Others, who need a reference in order to identify the notes, possess Relative Pitch (RP). The AP ability is assumed to reflect a unique, language-like representation of non-lexical musical notes in memory. The purpose of this study was to examine this assumption by comparing Event Related Potentials (ERP) of musicians with and without AP, to lexical and non-lexical representation of musical material. Subjects were eighteen young adult musicians. Seven were AP and eleven RP. Auditory stimuli, presented through earphones, were piano notes (non-lexical) or a voice saying the note's name (lexical). Visual stimuli, presented on a computer display were note symbols (non-lexical) or letters (lexical). Subjects performed a number of tasks, combining the two modalities (visual and auditory) and stimulus types (lexical and non-lexical), and reaction times (RT), performance accuracy and evoked potentials were recorded. The tasks forced the subjects to transfer mental representations of musical material from one mode to another. Our most important findings were the differences, between groups, in the scalp distribution of P300 amplitudes. We conclude that absolute pitch possessors use the same internal language as relative pitch possessors, when possible, but the distribution of the underlying brain activity is different between AP and RP subjects.

  17. Absolute MR thermometry using nanocarriers.

    Science.gov (United States)

    Deckers, Roel; Sprinkhuizen, Sara M; Crielaard, Bart J; Ippel, Johannes H; Boelens, Rolf; Bakker, Chris J G; Storm, Gert; Lammers, Twan; Bartels, Lambertus W

    2014-01-01

    Accurate time-resolved temperature mapping is crucial for the safe use of hyperthermia-mediated drug delivery. We here propose a magnetic resonance imaging temperature mapping method in which drug delivery systems serve not only to improve tumor targeting, but also as an accurate and absolute nano-thermometer. This method is based on the temperature-dependent chemical shift difference between water protons and the protons in different groups of drug delivery systems. We show that the chemical shift of the protons in the ethylene oxide group in polyethylene glycol (PEG) is temperature-independent, whereas the proton resonance of water decreases with increasing temperature. The frequency difference between both resonances is linear and does not depend on pH and physiological salt conditions. In addition, we show that the proton resonance of the methyl group in N-(2-hydroxypropyl)-methacrylamide (HPMA) is temperature-independent. Therefore, PEGylated liposomes, polymeric mPEG-b-pHPMAm-Lac2 micelles and HPMA copolymers can provide a temperature-independent reference frequency for absolute magnetic resonance (MR) thermometry. Subsequently, we show that multigradient echo MR imaging with PEGylated liposomes in situ allows accurate, time-resolved temperature mapping. In conclusion, nanocarrier materials may serve as highly versatile tools for tumor-targeted drug delivery, acting not only as hyperthermia-responsive drug delivery systems, but also as accurate and precise nano-thermometers. Copyright © 2014 John Wiley & Sons, Ltd.

  18. Absolute calibration of space-resolving soft X-ray spectrograph for plasma diagnostics

    CERN Document Server

    Yoshikawa, M; Kawamori, E; Watanabe, Y; Watabe, C; Yamaguchi, N; Tamano, T

    2001-01-01

    A grazing incidence flat-field soft X-ray (20-350 A) spectrograph was constructed and applied for impurity diagnostics in the GAMMA 10 fusion plasma. The spectrograph consisted of a limited height entrance slit, an aberration-corrected concave grating, a microchannel-plate intensified detector and an instant camera/a high speed solid state camera. An absolute calibration experiment for the SX spectrograph was performed at the Photon Factory in the High Energy Accelerator Research Organization with monitoring the incident synchrotron beam intensity by using an absolutely calibrated XUV silicon photodiode. From the results of absolute calibration of the spectrograph, the radiation loss from the plasma was obtained.

  19. Absolute calibration of space-resolving soft X-ray spectrograph for plasma diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, M. E-mail: yosikawa@prc.tsukuba.ac.jp; Okamoto, Y.; Kawamori, E.; Watanabe, Y.; Watabe, C.; Yamaguchi, N.; Tamano, T

    2001-07-21

    A grazing incidence flat-field soft X-ray (20-350 A) spectrograph was constructed and applied for impurity diagnostics in the GAMMA 10 fusion plasma. The spectrograph consisted of a limited height entrance slit, an aberration-corrected concave grating, a microchannel-plate intensified detector and an instant camera/a high speed solid state camera. An absolute calibration experiment for the SX spectrograph was performed at the Photon Factory in the High Energy Accelerator Research Organization with monitoring the incident synchrotron beam intensity by using an absolutely calibrated XUV silicon photodiode. From the results of absolute calibration of the spectrograph, the radiation loss from the plasma was obtained.

  20. Reducing risk where tectonic plates collide

    Science.gov (United States)

    Gomberg, Joan S.; Ludwig, Kristin A.

    2017-06-19

    Most of the world’s earthquakes, tsunamis, landslides, and volcanic eruptions are caused by the continuous motions of the many tectonic plates that make up the Earth’s outer shell. The most powerful of these natural hazards occur in subduction zones, where two plates collide and one is thrust beneath another. The U.S. Geological Survey’s (USGS) “Reducing Risk Where Tectonic Plates Collide—A USGS Plan to Advance Subduction Zone Science” is a blueprint for building the crucial scientific foundation needed to inform the policies and practices that can make our Nation more resilient to subduction zone-related hazards.

  1. "Absolute" sterility and "absolute" freedom from particle contamination.

    Science.gov (United States)

    Knapp, J Z

    1998-01-01

    Until the recent past, sterility of an injectable product was only discussed in absolute terms. Any description of sterility other than as an absolute could simply not be envisioned. While dealing in absolute yes/no statements is philosophically satisfying, these yes/no statements can't accommodate all real world scientific problems. Among these problems is the sterility problems faced in the mass production of injectable compounds. Many descriptions of procedures employed to achieve sterility in parenteral production batches were reported in the literature. The theoretical framework that could unite the widespread observations and practices into practical methodology was missing until recently. Production line control of the sterility of injectable products was essentially based on gut evaluations. The present achievement of rational, production line control of product sterility is based on the recognition that product sterility could not be simply regarded as a sharply edged yes/no affair. The present rational control is based on the fact that the sterility of a product is determined by the degree of contamination in the product prior to sterilization and to the parameters of the sterilization process. The end result of the sterilization process is now described as a probabalistic reduction of the initial contamination. The essential laboratory measurements on which this conclusion was based is due to Pflug (1-3). He assembled a theoretical framework, based on experimental data, that characterizes the sterility achieved in an injectable product with a single number. The end result of the sterilization process is now described as a probabalistic reduction of the initial contamination. As in many disciplines, the ability to achieve an objective evaluation of this important attribute provided the basis for scientific analysis, improved control and thus improved production and reduced cost. An equivalent framework is essential for the communication and

  2. Create Your Plate

    Medline Plus

    Full Text Available ... Pacific Islanders American Indian/Alaska Native Programs Older Adults Family Link Diabetes EXPO Upcoming Diabetes EXPOs EXPO ... Plate! Click on the plate sections below to add your food choices. Reset Plate Share Create Your ...

  3. Isla Guadalupe, Mexico (GUAX, SCIGN/PBO) a Relative Constraint for California Borderland and Northern Gulf of California Motions.

    Science.gov (United States)

    Gonzalez-Garcia, J. J.

    2004-12-01

    Using ITRF2000 as a common reference frame link, I analyzed survey mode and permanent GPS published results, together with SOPAC public data and results (http://sopac.ucsd.edu), in order to evaluate relative present day crustal deformation in California and northern Mexico. The crustal velocity field of Mexico (Marquez-Azua and DeMets, 2003) obtained from continuous GPS measurements conducted by Instituto Nacional de Geografia e Informatica (INEGI) for 1993-2001, was partially used. The preferred model for an instantaneous rigid motion between North-America and Pacific plates (NAPA), is obtained using results of Isla Guadalupe GPS surveys (1991-2002) giving a new constraint for Pacific plate (PA) motion (Gonzalez-Garcia et al., 2003). It produces an apparent reduction of 1 mm/yr in the absolute motion in the border zone between PA and North-America (NA) plates in this region, as compared with other GPS models (v.g. Prawirodirdjo and Bock, 2004); and it is 3 mm/yr higher than NNRNUVEL-1A. In the PA reference frame, westernmost islands from San Francisco (FARB), Los Angeles (MIG1), and Ensenada (GUAX); give current residuals of 1.8, 1.7 and 0.9 mm/yr and azimuths that are consistent with local tectonic setting, respectively. In the NA reference frame, besides the confirmation of 2 mm/yr E-W extension for the southern Basin and Range province in northern Mexico; a present day deformation rate of 40.5 mm/yr between San Felipe, Baja California (SFBC) and Hermosillo, Sonora, is obtained. This rate agrees with a 6.3 to 6.7 Ma for the "initiation of a full sea-floor spreading" in the northern Gulf of California. SFBC has a 7 mm/yr motion in the PA reference frame, giving then, a full NAPA theoretical absolute motion of 47.5 mm/yr. For Puerto Penasco, Sonora (PENA) there is a NAPA motion of 46.2 mm/yr and a residual of 1.2 mm/yr in the NA reference frame, this site is located only 75 km to the northeast from the Wagner basin center. For southern Isla Guadalupe (GUAX) there

  4. Periodic Boundary Motion in Thermal Turbulence

    International Nuclear Information System (INIS)

    Zhang, Jun; Libchaber, Albert

    2000-01-01

    A free-floating plate is introduced in a Benard convection cell with an open surface. It partially covers the cell and distorts the local heat flux, inducing a coherent flow that in turn moves the plate. Remarkably, the plate can be driven to a periodic motion even under the action of a turbulent fluid. The period of the oscillation depends on the coverage ratio, and on the Rayleigh number of the convective system. The plate oscillatory behavior observed in this experiment may be related to a geological model, in which continents drift in a quasiperiodic fashion. (c) 2000 The American Physical Society

  5. High accuracy absolute distance metrology

    Science.gov (United States)

    Swinkels, Bas L.; Bhattacharya, Nandini; Verlaan, Ad L.; Braat, Joseph J. M.

    2017-11-01

    One of ESA's future missions is the Darwin Space Interferometer, which aims to detect planets around nearby stars using optical aperture synthesis with free-flying telescopes. Since this involves interfering white (infra-red) light over large distances, the mission is not possible without a complex metrology system that monitors various speeds, distances and angles between the satellites. One of its sub-systems should measure absolute distances with an accuracy of around 70 micrometer over distances up to 250 meter. To enable such measurements, we are investigating a technique called frequency sweeping interferometry, in which a single laser is swept over a large known frequency range. Central to our approach is the use of a very stable, high finesse Fabry-Ṕerot cavity, to which the laser is stabilized at the endpoints of the frequency sweep. We will discuss the optical set-up, the control system that controls the fast sweeping, the calibration and the data analysis. We tested the system using long fibers and achieved a repeatability of 50 micrometers at a distance of 55 meters. We conclude with some recommendations for further improvements and the adaption for use in space.

  6. Global crustal movement and tectonic plate boundary deformation constrained by the ITRF2008

    Directory of Open Access Journals (Sweden)

    Zhu Ze

    2012-08-01

    Full Text Available On the basis of the newly released International Terrestrial Reference Frame(ITRF2008 by the International Earth Rotation Service (IERS, a new global plate model ITRF2008 plate for the major plates is established. This ITRF2008-derived model is analyzed in comparison with NNR-NUVEL1A model, which is mainly based on geological and geophysical data. The Eurasia and Pacific plates display obvious differences in terms of the velocity fields derived from the two plate motion models. Plate acceleration is also introduced to characterize the differences of the two velocity fields which obtained from ITRF2008 -plate and NNR-NUVEL1A models for major individual plates. The results show that the Africa, South America and Eurasia plates are undergoing acceleration, while the North America and Australia plates are in the state of deceleration motion.

  7. Absolute and convective instabilities in combined Couette-Poiseuille flow past a neo-Hookean solid

    Science.gov (United States)

    Patne, Ramkarn; Shankar, V.

    2017-12-01

    Temporal and spatio-temporal stability analyses are carried out to characterize the occurrence of convective and absolute instabilities in combined Couette-Poiseuille flow of a Newtonian fluid past a deformable, neo-Hookean solid layer in the creeping-flow limit. Plane Couette flow of a Newtonian fluid past a neo-Hookean solid becomes temporally unstable in the inertia-less limit when the parameter Γ = V η/(GR) exceeds a critical value. Here, V is the velocity of the top plate, η is the fluid viscosity, G is the shear modulus of the solid layer, and R is the fluid layer thickness. The Kupfer-Bers method is employed to demarcate regions of absolute and convective instabilities in the Γ-H parameter space, where H is the ratio of solid to fluid thickness in the system. For certain ranges of the thickness ratio H, we find that the flow could be absolutely unstable, and the critical Γ required for absolute instability is very close to that for temporal instability, thus making the flow absolutely unstable at the onset of temporal instability. In some cases, there is a gap in the parameter Γ between the temporal and absolute instability boundaries. The present study thus shows that absolute instabilities are possible, even at very low Reynolds numbers in flow past deformable solid surfaces. The presence of absolute instabilities could potentially be exploited in the enhancement of mixing at low Reynolds numbers in flow through channels with deformable solid walls.

  8. 242Pu absolute neutron-capture cross section measurement

    Science.gov (United States)

    Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; Bucher, B.; Chyzh, A.; Bredeweg, T. A.; Baramsai, B.; Couture, A.; Jandel, M.; Mosby, S.; O'Donnell, J. M.; Ullmann, J. L.

    2017-09-01

    The absolute neutron-capture cross section of 242Pu was measured at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array along with a compact parallel-plate avalanche counter for fission-fragment detection. During target fabrication, a small amount of 239Pu was added to the active target so that the absolute scale of the 242Pu(n,γ) cross section could be set according to the known 239Pu(n,f) resonance at En,R = 7.83 eV. The relative scale of the 242Pu(n,γ) cross section covers four orders of magnitude for incident neutron energies from thermal to ≈ 40 keV. The cross section reported in ENDF/B-VII.1 for the 242Pu(n,γ) En,R = 2.68 eV resonance was found to be 2.4% lower than the new absolute 242Pu(n,γ) cross section.

  9. 242Pu absolute neutron-capture cross section measurement

    Directory of Open Access Journals (Sweden)

    Buckner M.Q.

    2017-01-01

    Full Text Available The absolute neutron-capture cross section of 242Pu was measured at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array along with a compact parallel-plate avalanche counter for fission-fragment detection. During target fabrication, a small amount of 239Pu was added to the active target so that the absolute scale of the 242Pu(n,γ cross section could be set according to the known 239Pu(n,f resonance at En,R = 7.83 eV. The relative scale of the 242Pu(n,γ cross section covers four orders of magnitude for incident neutron energies from thermal to ≈ 40 keV. The cross section reported in ENDF/B-VII.1 for the 242Pu(n,γ En,R = 2.68 eV resonance was found to be 2.4% lower than the new absolute 242Pu(n,γ cross section.

  10. Absolutely summing multilinear operators: a Panorama | Pellegrino ...

    African Journals Online (AJOL)

    This paper has a twofold purpose: to present an overview of the theory of absolutely summing operators and its different generalizations for the multilinear setting, and to sketch the beginning of a research project related to an objective search of “perfect” multilinear extensions of the ideal of absolutely summing operators.

  11. MEAN OF MEDIAN ABSOLUTE DERIVATION TECHNIQUE MEAN ...

    African Journals Online (AJOL)

    eobe

    The accurate estimation of noise variance in an image is the first important stage ... lung image was lung image was developed. developed. developed. The development of mean of median absolute derivation technique development of mean of median absolute .... that are non-real numbers during initial processing.

  12. Quantum nonequilibrium equalities with absolute irreversibility

    Science.gov (United States)

    Funo, Ken; Murashita, Yûto; Ueda, Masahito

    2015-07-01

    We derive quantum nonequilibrium equalities in absolutely irreversible processes. Here by absolute irreversibility we mean that in the backward process the density matrix does not return to the subspace spanned by those eigenvectors that have nonzero weight in the initial density matrix. Since the initial state of a memory and the postmeasurement state of the system are usually restricted to a subspace, absolute irreversibility occurs during the measurement and feedback processes. An additional entropy produced in absolutely irreversible processes needs to be taken into account to derive nonequilibrium equalities. We discuss a model of a feedback control on a qubit system to illustrate the obtained equalities. By introducing N heat baths each composed of a qubit and letting them interact with the system, we show how the entropy reduction via feedback control can be converted into work. An explicit form of extractable work in the presence of absolute irreversibility is given.

  13. Litho-tectonic mapping of the North Afar region from Sentinel-2A multispectral imagery and ALOS AW3D30 digital elevation data: Controls on Danakil-Nubia plate motion between the Erta'Ale ridge and the Gulf of Zula

    Science.gov (United States)

    Hartnady, Chris; Hartnady, Michael; Wise, Edward; Blake, Dylan; McGibbon, David; Hay, E. Rowena

    2017-04-01

    The Danakil Depression in the North Afar region of Ethiopia reaches elevations deeper than 120 m below sea level and contains a Pleistocene-Holocene evaporite sequence currently investigated for potash mineral deposits. Separated from the main Ethiopian escarpment by the Dogua horst mountains, the asymmetric half-graben is bordered on its western (Nubian) side by the active, normal Main Danakil Rift-border Fault (MDRF). Above the MDRF, a series of piedmont alluvial fans (bajadas) fringes the Dogua Horst, emanating from a series of wadi catchments between the larger perennial rivers (Ragali, Saba) that drain from the high (>2000 m) Ethiopian Plateau. On its eastern side, the Danakil block contains Proterozoic-Palaeozoic sequences correlated with similar units in the Dogua range, and forms a microplate rotating independently between the larger Nubian and Arabian plates (McClusky et al., 2010). An understanding of the sedimentary and tectonic evolution of the Danakil-Nubia (DA-NU) plate system is crucial to the beneficial development of fresh groundwater resources and to an assessment of seismotectonic and volcanic geohazards in the area. Between the Mt Alid caldera in the Dandeiro graben and the Erta'Ale crater in the south Danakil, the rate of present-day DA-NU motion is 10.9 - 13.5 mm/yr, with direction azimuths N106E- N096E (after Schettino et al., 2016). DA-NU relative motion is focussed along the east-dipping MDRF in the Danakil but switches to an eastern (west-dipping) rift-border normal fault in the Dandiero, a northward extension of the Renda-Maglalla-Coma graben, separating the Dogua Horst from the main part of the NU plate. This change in rifting asymmetry occurs across a WNW/ESE-striking zone of basement faulting that terminates the Dogua Horst and functions as a left-stepping proto-transform fault zone, across the NNW direction of DA-NU proto-rift propagation. From 13-channel multispectral data of the European Space Agency satellite Sentinel-2A, a false

  14. Nonlinear vibration of thick FGM plates on elastic foundation subjected to thermal and mechanical loads using the first-order shear deformation plate theory

    OpenAIRE

    Nguyen Dinh Duc; Pham Hong Cong

    2015-01-01

    This paper presents an analytical approach to investigate the nonlinear dynamic response and vibration of thick functionally graded material (FGM) plates using both of the first-order shear deformation plate theory and stress function with full motion equations (not using Volmir’s assumptions). The FGM plate is assumed to rest on elastic foundation and subjected to mechanical, thermal, and damping loads. Numerical results for dynamic response of the FGM plate are obtained by Runge–Kutta metho...

  15. Comparison of pressure plate and force plate gait kinetics in sound Warmbloods at walk and trot.

    Science.gov (United States)

    Oosterlinck, Maarten; Pille, Frederik; Huppes, Tsjester; Gasthuys, Frank; Back, Willem

    2010-12-01

    Modern pressure plates (PP) could be an alternative to traditional force plates (FP) for quantitative equine gait analysis, thereby providing the clinician with objective data on the horse's gait while unravelling the loading of different regions of the hoof during the stance phase. The aim of this study was to determine whether a stand-alone PP allows reliable measurement of gait kinetics, compared to simultaneously recorded FP variables. Six sound Warmblood horses were walked and trotted over a combined PP and FP system for collection of a set of five valid kinetic measurements for each forelimb. A measurement was considered valid if the horse was moving in a straight line at a constant pace while gait velocity was within a preset range and the hoof fully contacted the plate surface. Significant differences between FP and PP data were seen for peak vertical force (PVF), vertical impulse (VI), time at which the PVF occurs (tPVF) and forelimb symmetry ratios (SymPVF and SymVI) (P 20%). The results indicate that a stand-alone pressure plate can be used to measure absolute (ST) and relative (tPVF) temporal variables and loading symmetry ratios and offers equine veterinarians a mobile, cost-efficient and quick gait evaluation method for routine clinical use. However, the system cannot be used interchangeably with a force plate to measure absolute values of limb loading. Copyright © 2009 Elsevier Ltd. All rights reserved.

  16. Biomechanical comparison of a lateral polyaxial locking plate with a posterolateral polyaxial locking plate applied to the distal fibula.

    Science.gov (United States)

    Hallbauer, Jakob; Klos, Kajetan; Rausch, Sascha; Gräfenstein, Andreas; Wipf, Felix; Beimel, Claudia; Hofmann, Gunther; Mückley, Thomas

    2014-09-01

    Polyaxial locking plates are becoming popular for the fixation of distal fibula fractures. This study establishes how construct stiffness and plate loosening, measured as range of motion, differs between lateral and posterolateral plate location. Seven matched pairs of cadaver fibulae were osteotomized in standardized fashion to produce a Weber type B distal fibula fracture. The fragments were fixated with an interfragmentary lag screw and polyaxial locking plates, with one fibula in each pair receiving a posterolateral anti-glide-plate, and the other a lateral neutralization-plate. In a biomechanical test, the bending and torsional stiffnesses of the constructs and the ranges of motion (ROM) were measured and subjected to a paired comparison. The laterally plated group had a higher median (interquartile range) bending stiffness (29.2 (19.7) N/mm) and a smaller range of motion (2.06 (1.99) mm) than the posterolaterally plated group (14.6 (20.6) N/mm, and 4.11 (3.28) mm, respectively); however, the results were not statistically significant (pbending=0.314; pROM=0.325). Similarly, the torsional stiffness did not differ significantly between the two groups (laterally plated: 426 (259) Nmm/°; posterolaterally plated: 248 (399) Nmm/°; ptorsion=0.900). The range of motion measurements between the two groups under torsional loading were also statistically insignificant (laterally plated: 8.88 (6.30) mm; posterolaterally plated: 15.34 (12.64) mm; pROM=0.900). In biomechanical cadaver-model tests of Weber type B fracture fixation with polyaxial locking plates, laterally plated constructs and posterolaterally plated constructs performed without significantly difference. Therefore, other considerations, such as access morbidity, associated injuries, patient anatomy, or surgeon's preference, may guide the choice of plating pattern. Further clinical studies will be needed for the establishment of definitive recommendations. Information on the behavior of polyaxial locking

  17. Create Your Plate

    Medline Plus

    Full Text Available ... Student Resources History of Diabetes Resources for School Projects How to Reference Our Site Diabetes Basics Myths ... Your Plate It's simple and effective for both managing diabetes and losing weight. Creating your plate lets ...

  18. Create Your Plate

    Medline Plus

    Full Text Available ... Planning Meals Diabetes Meal Plans Create Your Plate Gluten Free Diets Meal Planning for Vegetarian Diets Cook ... Create Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook with Heart- ...

  19. Create Your Plate

    Medline Plus

    Full Text Available ... Your Plate Gluten Free Diets Meal Planning for Vegetarian Diets Cook with Heart-Healthy Foods Holiday Meal ... Healthy Diet Create Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook ...

  20. Create Your Plate

    Medline Plus

    Full Text Available ... Your Plate It's simple and effective for both managing diabetes and losing weight. Creating your plate lets you still choose the foods you want, but changes the portion sizes so you are getting larger ...

  1. Williamson Polishing & Plating Site

    Science.gov (United States)

    Williamson Polishing & Plating Co. Inc. was a plating shop located in the Martindale-Brightwood neighborhood of Indianapolis. The facility conducted job shop polishing and electroplating services. The vacant site contains a 14,651-square-foot building.

  2. A Possible Differentially Shortened Strike-slip Plate Boundary: the Okhotsk Plate Example.

    Science.gov (United States)

    Hindle, D.; Egorov, V.; Mackey, K. G.; Fujita, K.

    2004-12-01

    The Okhotsk plate has been postulated based on a combination of GPS geodetic inversions (REVEL1), seimsicity, geologic and lineament data. Lying between the North American and Eurasian plates, its northwestern corner would appear to be undergoing compression in a scissors motion between the two bounding plates. Extrusion tectonics along multiple, large strike-slip faults within the Okhotsk plate itself have been suggested to allow the escape of material away from the apex of Eurasia-North America. The plate boundary between Okhotsk and North America has been suggested to be diffuse, based on widely scattered minor seismicity. However, the large, left lateral, Ulakhan fault has also been suggested as a candidate plate boundary. We present field geological and geomorphological evidence of the partitioning of deformation between the Ulakhan fault, and several parallel and oblique, linked faults. The Ulakhan fault strand appears to have a maximum displacement of 24 km based on river valley offsets and closing large pull apart basins. Some of the displacement from the Ulakhan fault appears relayed into the plate margin along oblique trending, thrust/oblique slip faults. Estimated shortening over these faults is equivalent to the amount of shortening relayed into the plate margin from the plate boundary. There may be several thrust/oblique slip faults along the Ulakhan fault, which leads to the interesting situation of a segmented, strike-slip plate boundary being actively shortened in a margin parallel direction. This may be the result of postulated extrusion of the Okhotsk plate due to North America/Eurasia convergence. Such a situation would have important consequences for the interpretation of GPS data in a plate tectonic context.

  3. Flow of nanofluid past a Riga plate

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Adeel, E-mail: adeelahmed@comsats.edu.pk [Department of Mathematics, COMSATS Institute of Information Technology, Park Road, Chak Shahzad, 44000 Islamabad (Pakistan); Laboratoire J.A. Dieudonné, Université de Nice Sophia Antipolis, Parc Valrose, 06108 Nice (France); Asghar, Saleem [Department of Mathematics, COMSATS Institute of Information Technology, Park Road, Chak Shahzad, 44000 Islamabad (Pakistan); Department of Mathematics, King Abdul Aziz University, Jeddah (Saudi Arabia); Afzal, Sumaira [Department of Mathematics, COMSATS Institute of Information Technology, Park Road, Chak Shahzad, 44000 Islamabad (Pakistan)

    2016-03-15

    This paper studies the mixed convection boundary layer flow of a nanofluid past a vertical Riga plate in the presence of strong suction. The mathematical model incorporates the Brownian motion and thermophoresis effects due to nanofluid and the Grinberg-term for the wall parallel Lorentz force due to Riga plate. The analytical solution of the problem is presented using the perturbation method for small Brownian and thermophoresis diffusion parameters. The numerical solution is also presented to ensure the reliability of the asymptotic method. The comparison of the two solutions shows an excellent agreement. The correlation expressions for skin friction, Nusselt number and Sherwood number are developed by performing linear regression on the obtained numerical data. The effects of nanofluid and the Lorentz force due to Riga plate, on the skin friction are discussed. - Highlights: • Mixed convection flow of a nanofluid past a vertical Riga plate. • The Brownian motion and thermophoresis effects due to nanofluid are incorporated. • Grinberg-term represents the wall parallel Lorentz force due to Riga plate. • The correlation expressions for skin friction, Nusselt and Sherwood numbers are developed. • The effects of nanofluid and the Lorentz force on the skin friction are discussed.

  4. Influence of obliquely subducting slab on Pacific-North America shear motion inferred from seismic anisotropy along the Queen Charlotte margin

    Science.gov (United States)

    Cao, L.; Kao, H.; Wang, K.; Wang, Z.

    2016-12-01

    Haida Gwaii is located along the transpressive Queen Charlotte margin between the Pacific (PA) and North America (NA) plates. The highly oblique relative plate motion is partitioned, with the strike-slip component accommodated by the Queen Charlotte Fault (QCF) and the convergent component by a thrust fault offshore. To understand how the presence of a obliquely subducting slab influences shear deformation of the plate boundary, we investigate mantle anisotropy by analyzing shear-wave splitting of teleseismic SKS phases recorded at 17 seismic stations in and around Haida Gwaii. We used the MFAST program to determine the polarization direction of the fast wave (φ) and the delay time (δt) between the fast and slow phases. The fast directions derived from stations on Haida Gwaii and two stations to the north on the Alaska Panhandle are predominantly margin-parallel (NNW). However, away from the plate boundary, the fast direction transitions to WSW-trending, very oblique or perpendicular to the plate boundary. Because the average delay time of 0.6-2.45 s is much larger than values based on an associated local S phase splitting analysis in the same study area, it is reasonable to infer that most of the anisotropy from our SKS analysis originates from the upper mantle and is associated with lattice-preferred orientation of anisotropic minerals. The margin-parallel fast direction within about 100 km of the QCF (average φ = -40º and δt = 1.2 s) is likely induced by the PA-NA shear motion. The roughly margin-normal fast directions farther away, although more scatterd, are consistent with that previously observed in the NA continent and are attributed to the absolute motion of the NA plate. However, the transition between the two regimes based on our SKS analysis appears to be gradual, suggesting that the plate boundary shear influences a much broader region at mantle depths than would be inferred from the surface trace of the QCF. We think this is due to the presence

  5. Absolute linear thermal-expansion measurements on copper and aluminum from 5 to 320 K

    International Nuclear Information System (INIS)

    Kroeger, F.R.; Swenson, C.A.

    1977-01-01

    A linear absolute dilatometer based on a three-terminal parallel-plate capacitor design has been used to obtain thermal expansion data for high-purity copper and aluminum from 5 to 320 K. These data have an absolute accuracy of +- 0.1% above 20 K for copper and above 30 K for aluminum, and agree well with published data at the higher temperatures. The disagreement which exists with other data below 5 K for copper and below 15 K for aluminum is believed to be sample dependent, but the mechanism is not known. The aluminum results in this region depend on the state of annealing of the sample

  6. The absolute environmental performance of buildings

    DEFF Research Database (Denmark)

    Brejnrod, Kathrine Nykjær; Kalbar, Pradip; Petersen, Steffen

    2017-01-01

    sustainability for the standard house were proposed focusing on three measures: minimizing environmental impacts from building construction, minimizing impacts from energy consumption during use phase, and reducing the living area per person. In an intermediate path, absolute sustainability can be obtained...... by reducing the impacts from construction by 89%, use phase energy consumption by 80%, and the living area by 60%.......Our paper presents a novel approach for absolute sustainability assessment of a building's environmental performance. It is demonstrated how the absolute sustainable share of the earth carrying capacity of a specific building type can be estimated using carrying capacity based normalization factors...

  7. Vibration of plates

    CERN Document Server

    Chakraverty, Snehashish

    2008-01-01

    Plates are integral parts of most engineering structures and their vibration analysis is required for safe design. This work provides a comprehensive introduction to vibration theory and analysis of two-dimensional plates. It offers information on vibration problems along with a discussion of various plate geometries and boundary conditions.

  8. ASTEROID ABSOLUTE MAGNITUDES V10.0

    Data.gov (United States)

    National Aeronautics and Space Administration — Absolute magnitudes and slopes, mostly IAU-adopted with exceptions noted, for all asteroids numbered as of the 2006 March 14 batch of Minor Planet Circulars.

  9. ASTEROID ABSOLUTE MAGNITUDES V11.0

    Data.gov (United States)

    National Aeronautics and Space Administration — Absolute magnitudes and slopes, mostly IAU-adopted with exceptions noted, for all asteroids numbered as of the 2007 April 2 batch of Minor Planet Circulars.

  10. ASTEROID ABSOLUTE MAGNITUDES V12.0

    Data.gov (United States)

    National Aeronautics and Space Administration — Absolute magnitudes and slopes, mostly IAU-adopted with exceptions noted, for all asteroids numbered as of the 2008 April 20 batch of Minor Planet Circulars.

  11. ASTEROID ABSOLUTE MAGNITUDES V7.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set tabulates the IAU-adopted absolute V magnitude and slope parameter for all numbered asteroids as of the given stop date. The data set is updated yearly.

  12. ASTEROID ABSOLUTE MAGNITUDES V9.0

    Data.gov (United States)

    National Aeronautics and Space Administration — Absolute magnitudes and slopes, mostly IAU-adopted with exceptions noted, for all asteroids numbered as of the 2005 April 7 batch of Minor Planet Circulars.

  13. ASTEROID ABSOLUTE MAGNITUDES V8.0

    Data.gov (United States)

    National Aeronautics and Space Administration — Absolute magnitudes and slopes, mostly IAU-adopted with exceptions noted, for all asteroids numbered as of the 2004 April 15 batch of Minor Planet Circulars

  14. Present-day stress fields of the Gulf of Suez (Egypt) based on exploratory well data: Non-uniform regional extension and its relation to inherited structures and local plate motion

    Science.gov (United States)

    Bosworth, William; Durocher, Scott

    2017-12-01

    The Gulf of Suez is the prototype model of a failed or aborted continental rift. However, the basin is seismically active and the footwalls of several major extensional faults continue to rise at the present time. Furthermore, decadal-length Global Positioning System (GPS) datasets demonstrate that the Sinai micro-plate continues to separate from Africa in a northerly direction at ∼0.15 cm/yr with a Gulf of Suez rift-normal component of ∼0.05 cm/yr. Geologic and GPS observations both indicate that the rift is now undergoing highly-oblique extension. Previous interpretations of borehole breakouts in industry exploration wells suggested that the minimum horizontal stress (Shmin) in the southern Gulf of Suez is presently aligned ∼015°. New subsurface data from the accommodation zone boundary between the Central and Darag (northern) sub-basins similarly identifies an extension direction of approximately N-S. By contrast, in the Central sub-basin itself breakout and drilling-induced fracture (DIF) data indicate NE-SW extension, or rift-normal movement that is similar to the documented older Miocene history of the entire basin. Based on these observations the present-day stress field of the Gulf of Suez is spatially non-uniform. Variations are also present in local and teleseismic datasets. The northern Gulf of Suez shows relatively less seismicity, with very few events greater than M = 3. The central sub-basin is very active, with 17 events M ≥ 3 during the past 45 years, and these suggest NE-SW extension similar to the breakout data. The southern Gulf of Suez is the most seismically active and merges with an area of significant seismicity in the northern Red Sea. In the southern Gulf of Suez the seismicity is complex but focal plane analyses of the two largest historical events indicated NNE-SSW extension, in agreement with the breakout data. Differing interpretations have been proposed for the smaller magnitude seismicity. We suggest that each of the three

  15. Absolutely uniform illumination of laser fusion pellets

    International Nuclear Information System (INIS)

    Schmitt, A.J.

    1984-01-01

    Absolutely uniform illumination of spherical laser fusion pellets is possible when the energy deposition from a single beam is given by a simple cos 2 theta distribution. Conditions can be derived for which the laser beam targeting angles allow this absolute illumination uniformity. Configurations based upon the cube and higher order Platonic solids satisfy the constraints, as well as an infinite class of other less symmetric configurations

  16. Absolutely uniform illumination of laser fusion pellets

    International Nuclear Information System (INIS)

    Schmitt, A.J.

    1984-01-01

    Absolutely uniform illumination of spherical laser fusion pellets is possible when the energy deposition from a single laser beam is given by a simple cos 2 theta distribution. Conditions can be derived for which the laser beam targeting angles allow this absolute illumination uniformity. Configurations based upon the cube and higher order Platonic solids satisfy the constraints, as well as infinite class of other less symmetric configurations

  17. Absolute spectrophotometry of Nova Cygni 1975

    International Nuclear Information System (INIS)

    Kontizas, E.; Kontizas, M.; Smyth, M.J.

    1976-01-01

    Radiometric photoelectric spectrophotometry of Nova Cygni 1975 was carried out on 1975 August 31, September 2, 3. α Lyr was used as reference star and its absolute spectral energy distribution was used to reduce the spectrophotometry of the nova to absolute units. Emission strengths of Hα, Hβ, Hγ (in W cm -2 ) were derived. The Balmer decrement Hα:Hβ:Hγ was compared with theory, and found to deviate less than had been reported for an earlier nova. (author)

  18. The Determination of Absolute Sea level Rise in New Zealand

    Science.gov (United States)

    Hannah, J.; Denys, P. H.; Beavan, R. J.

    2010-12-01

    Long term sea level trends at five New Zealand tide gauges with records > 60 yr in length have been determined through to the end of 2008. These gauges, with a wide spatial distribution, reveal an average relative sea level rise across of 1.7 ± 0.1 mm/yr. When a Glacial Isostatic adjustment (GIA) is applied using Peltier’s ICE 5G (v1.2) model, this estimated trend rises to 2.0 mm/yr. However, the absolute trends, when calculated using approximately 10 years of cGPS data at the four gauges with the longest records (Auckland, Wellington, Lyttelton and Dunedin), show a sea level rise of only 1.2 ± 0.4 mm/yr. If the Wellington gauge (located in the transitional plate boundary zone) is removed, this absolute trend rises to 1.4 mm/yr. This paper outlines how the above results were obtained and discusses proposed future research directions. It also includes previously unpublished data on relative sea level trends as determined at a further four New Zealand tide gauge sites.

  19. Analysis of Large Flexible Body Deformation in Multibody Systems Using Absolute Coordinates

    Energy Technology Data Exchange (ETDEWEB)

    Dombrowski, Stefan von [Institute of Robotics and Mechatronics, German Aerospace Center (DLR) (Germany)], E-mail: stefan.von.dombrowski@dlr.de

    2002-11-15

    To consider large deformation problems in multibody system simulations a finite element approach, called absolute nodal coordinate.formulation,has been proposed. In this formulation absolute nodal coordinates and their material derivatives are applied to represent both deformation and rigid body motion. The choice of nodal variables allows a fully nonlinear representation of rigid body motion and can provide the exact rigid body inertia in the case of large rotations. The methodology is especially suited for but not limited to modeling of beams, cables and shells in multibody dynamics.This paper summarizes the absolute nodal coordinate formulation for a 3D Euler-Bernoulli beam model, in particular the definition of nodal variables, corresponding generalized elastic and inertia forces and equations of motion. The element stiffness matrix is a nonlinear function of the nodal variables even in the case of linearized strain/displacement relations. Nonlinear strain/displacement relations can be calculated from the global displacements using quadrature formulae.Computational examples are given which demonstrate the capabilities of the applied methodology. Consequences of the choice of shape.functions on the representation of internal forces are discussed. Linearized strain/displacement modeling is compared to the nonlinear approach and significant advantages of the latter, when using the absolute nodal coordinate formulation, are outlined.

  20. An updated digital model of plate boundaries

    Science.gov (United States)

    Bird, Peter

    2003-03-01

    A global set of present plate boundaries on the Earth is presented in digital form. Most come from sources in the literature. A few boundaries are newly interpreted from topography, volcanism, and/or seismicity, taking into account relative plate velocities from magnetic anomalies, moment tensor solutions, and/or geodesy. In addition to the 14 large plates whose motion was described by the NUVEL-1A poles (Africa, Antarctica, Arabia, Australia, Caribbean, Cocos, Eurasia, India, Juan de Fuca, Nazca, North America, Pacific, Philippine Sea, South America), model PB2002 includes 38 small plates (Okhotsk, Amur, Yangtze, Okinawa, Sunda, Burma, Molucca Sea, Banda Sea, Timor, Birds Head, Maoke, Caroline, Mariana, North Bismarck, Manus, South Bismarck, Solomon Sea, Woodlark, New Hebrides, Conway Reef, Balmoral Reef, Futuna, Niuafo'ou, Tonga, Kermadec, Rivera, Galapagos, Easter, Juan Fernandez, Panama, North Andes, Altiplano, Shetland, Scotia, Sandwich, Aegean Sea, Anatolia, Somalia), for a total of 52 plates. No attempt is made to divide the Alps-Persia-Tibet mountain belt, the Philippine Islands, the Peruvian Andes, the Sierras Pampeanas, or the California-Nevada zone of dextral transtension into plates; instead, they are designated as "orogens" in which this plate model is not expected to be accurate. The cumulative-number/area distribution for this model follows a power law for plates with areas between 0.002 and 1 steradian. Departure from this scaling at the small-plate end suggests that future work is very likely to define more very small plates within the orogens. The model is presented in four digital files: a set of plate boundary segments; a set of plate outlines; a set of outlines of the orogens; and a table of characteristics of each digitization step along plate boundaries, including estimated relative velocity vector and classification into one of 7 types (continental convergence zone, continental transform fault, continental rift, oceanic spreading ridge

  1. Limits of mass-transfer in parallel plate dialyzers

    NARCIS (Netherlands)

    Kolev, S.D.; Kolev, Spas D.; van der Linden, W.E.

    1992-01-01

    The absolute limits of mass transfer across the membrane in a parallel-plate dialyser set by the flow pattern in both channels were determined on the basis of a mathematical model assuming axially dispersed plug flow. The lower limit corresponds to the case of mass transfer under laminar flow

  2. A global algorithm for estimating Absolute Salinity

    Directory of Open Access Journals (Sweden)

    T. J. McDougall

    2012-12-01

    Full Text Available The International Thermodynamic Equation of Seawater – 2010 has defined the thermodynamic properties of seawater in terms of a new salinity variable, Absolute Salinity, which takes into account the spatial variation of the composition of seawater. Absolute Salinity more accurately reflects the effects of the dissolved material in seawater on the thermodynamic properties (particularly density than does Practical Salinity.

    When a seawater sample has standard composition (i.e. the ratios of the constituents of sea salt are the same as those of surface water of the North Atlantic, Practical Salinity can be used to accurately evaluate the thermodynamic properties of seawater. When seawater is not of standard composition, Practical Salinity alone is not sufficient and the Absolute Salinity Anomaly needs to be estimated; this anomaly is as large as 0.025 g kg−1 in the northernmost North Pacific. Here we provide an algorithm for estimating Absolute Salinity Anomaly for any location (x, y, p in the world ocean.

    To develop this algorithm, we used the Absolute Salinity Anomaly that is found by comparing the density calculated from Practical Salinity to the density measured in the laboratory. These estimates of Absolute Salinity Anomaly however are limited to the number of available observations (namely 811. In order to provide a practical method that can be used at any location in the world ocean, we take advantage of approximate relationships between Absolute Salinity Anomaly and silicate concentrations (which are available globally.

  3. Gravitational Acceleration as a Cue for Absolute Size and Distance

    Science.gov (United States)

    Hecht, Heiko; Kaiser, Mary K.; Banks, Martin S.; Hart, Sandra G. (Technical Monitor)

    1994-01-01

    When an object's motion is influenced by gravity, such as the rise and fall of a thrown ball, the vertical component of acceleration is roughly constant at 9.8 m/sec2. In principle, an observer could use this information to estimate the absolute size and distance of the object (Saxberg, 1987a; Watson, Banks, von Hofsten, & Royden, 1992). In three experiments, we examined the ability to utilize the size and distance information provided by gravitational acceleration. Observers viewed computer simulations of an object rising and falling on a trajectory parallel to the gravitational vector. The simulated objects were three balls of different diameters presented across a wide range of simulated distances. Observers were asked to identify which ball was presented and the distance at which it was presented. The results of Experiment 1 showed that size and distance judgments were significantly better than chance, but not as accurate as expected if the information contained in the dynamics of free fall were used fully utilized. The results of Experiment 2 showed that acceleration information is used, but that observers can also make use of velocity information. Finally, the results of Experiment 3 showed that observers can use projected size information, but that their size and distance judgments are much more accurate when motion information is present as well. These results show that observers can use the information in the dynamics of free fall to estimate absolute size and distance, but their estimates are not as accurate as they could be if the information were used effectively.

  4. Thermodynamic energy exchange in a moving plate capacitor.

    Science.gov (United States)

    Davis, B. R.; Abbott, D.; Parrondo, J. M. R.

    2001-09-01

    In this paper we describe an apparent paradox concerning a moving plate capacitor driven by thermal noise from a resistor. The plates are attracted together, but a demon restores the plates of the capacitor to their original position when the voltage across the capacitor is small-hence only small forces are present for the demon to work against. The demon has to work harder than this to avoid the situation of perpetual motion, but the open question is how? This is unsolved, however we explore the concept of a moving plate capacitor by examining the case where it is still excited by thermal noise, but where the restoring force on the capacitor plates is provided by a simple spring rather than some unknown demon. We display simulation results with interesting behavior, particularly where the capacitor plates collide with each other. (c) 2001 American Institute of Physics.

  5. Jasminum flexile flower absolute from India--a detailed comparison with three other jasmine absolutes.

    Science.gov (United States)

    Braun, Norbert A; Kohlenberg, Birgit; Sim, Sherina; Meier, Manfred; Hammerschmidt, Franz-Josef

    2009-09-01

    Jasminum flexile flower absolute from the south of India and the corresponding vacuum headspace (VHS) sample of the absolute were analyzed using GC and GC-MS. Three other commercially available Indian jasmine absolutes from the species: J. sambac, J. officinale subsp. grandiflorum, and J. auriculatum and the respective VHS samples were used for comparison purposes. One hundred and twenty-one compounds were characterized in J. flexile flower absolute, with methyl linolate, benzyl salicylate, benzyl benzoate, (2E,6E)-farnesol, and benzyl acetate as the main constituents. A detailed olfactory evaluation was also performed.

  6. Absolute calibration in vivo measurement systems

    International Nuclear Information System (INIS)

    Kruchten, D.A.; Hickman, D.P.

    1991-02-01

    Lawrence Livermore National Laboratory (LLNL) is currently investigating a new method for obtaining absolute calibration factors for radiation measurement systems used to measure internally deposited radionuclides in vivo. Absolute calibration of in vivo measurement systems will eliminate the need to generate a series of human surrogate structures (i.e., phantoms) for calibrating in vivo measurement systems. The absolute calibration of in vivo measurement systems utilizes magnetic resonance imaging (MRI) to define physiological structure, size, and composition. The MRI image provides a digitized representation of the physiological structure, which allows for any mathematical distribution of radionuclides within the body. Using Monte Carlo transport codes, the emission spectrum from the body is predicted. The in vivo measurement equipment is calibrated using the Monte Carlo code and adjusting for the intrinsic properties of the detection system. The calibration factors are verified using measurements of existing phantoms and previously obtained measurements of human volunteers. 8 refs

  7. The San Andreas fault experiment. [gross tectonic plates relative velocity

    Science.gov (United States)

    Smith, D. E.; Vonbun, F. O.

    1973-01-01

    A plan was developed during 1971 to determine gross tectonic plate motions along the San Andreas Fault System in California. Knowledge of the gross motion along the total fault system is an essential component in the construction of realistic deformation models of fault regions. Such mathematical models will be used in the future for studies which will eventually lead to prediction of major earthquakes. The main purpose of the experiment described is the determination of the relative velocity of the North American and the Pacific Plates. This motion being so extremely small, cannot be measured directly but can be deduced from distance measurements between points on opposite sites of the plate boundary taken over a number of years.

  8. Motion and volumetric change as demonstrated by 4DCT: The effects of abdominal compression on the GTV, lungs, and heart in lung cancer patients.

    Science.gov (United States)

    Rasheed, Abdullah; Jabbour, Salma K; Rosenberg, Stephen; Patel, Ajay; Goyal, Sharad; Haffty, Bruce G; Yue, Ning J; Khan, Alvin

    2016-01-01

    Lung tumors move during respiration, complicating radiation therapy. The abdominal compression plate (ACP) is thought to reduce respiratory motion. This study quantifies ACP efficacy on respiratory-induced motion by using 4-dimensional computed tomography to evaluate volume and displacement changes of the heart, lungs, and tumor with and without ACP. Lung cancer patients (n = 17) received 4-dimensional computed tomography simulations (10 computed tomography scans from 0% to 90% breathing phases) with and without ACP under maximally tolerated diaphragmatic pressure. Gross tumor volume (GTV), heart, and lungs were contoured in treatment planning software for each phase. Structures were exported for analysis. For each phase, with and without ACP, tumor and organ absolute centroid range of motion and volume were calculated. ACP did not significantly affect GTV, heart, or lung motion on the sample as a whole, but instead demonstrated patient-specific results. ACP reduced GTV motion in 3 (17.6%; 3 upper lobe tumors) by 2.9 mm (P lung range of motion was 7.4 mm, 11.8 mm, and 11.9 mm, respectively, without compression and 4.5 mm, 8.4 mm, and 10.9 mm, respectively, with compression. Averaged across the sample, ACP did not exhibit any axis-specific effect. ACP efficacy was patient-specific, possibly because of pre-existing factors including chronic obstructive pulmonary disease severity, chest wall elasticity, tumor location, and patient comfort. Tumor lobe location does not predetermine compression efficacy; therefore, patients should be simulated with and without ACP, regardless of tumor location. GTV motion seems most important in determining suitability for compression. Alternative motion control should be considered in patients not benefited by compression. In patients who benefited, ACP may enhance tumor coverage while minimizing toxicity. Larger scale studies are necessary for definitive treatment recommendations. Copyright © 2016 American Society for Radiation

  9. Gravitational acceleration as a cue for absolute size and distance?

    Science.gov (United States)

    Hecht, H.; Kaiser, M. K.; Banks, M. S.

    1996-01-01

    When an object's motion is influenced by gravity, as in the rise and fall of a thrown ball, the vertical component of acceleration is roughly constant at 9.8 m/sec2. In principle, an observer could use this information to estimate the absolute size and distance of the object (Saxberg, 1987a; Watson, Banks, von Hofsten, & Royden, 1992). In five experiments, we examined people's ability to utilize the size and distance information provided by gravitational acceleration. Observers viewed computer simulations of an object rising and falling on a trajectory aligned with the gravitational vector. The simulated objects were balls of different diameters presented across a wide range of simulated distances. Observers were asked to identify the ball that was presented and to estimate its distance. The results showed that observers were much more sensitive to average velocity than to the gravitational acceleration pattern. Likewise, verticality of the motion and visibility of the trajectory's apex had negligible effects on the accuracy of size and distance judgments.

  10. In vitro comparison of bioresorbable and titanium anterior cervical plates in the immediate postoperative condition.

    Science.gov (United States)

    Freeman, Andrew L; Derincek, Alihan; Beaubien, Brian P; Buttermann, Glenn R; Lew, William D; Wood, Kirkham B

    2006-12-01

    Bioresorbable plates have recently been used with anterior cervical discectomy and fusion (ACDF). Compared with metallic plates, bioresorbable plates provide segmental stabilization with minimal imaging artifact, eventual resorption, and increased load sharing. The objectives of the present study were to determine whether a bioresorbable plate can withstand simulated physiologic static and cyclic loading, to compare the reduction in flexibility provided by bioresorbable and titanium plates, and to quantify load sharing between the plate and spine with graft. Sixteen human cervical motion segments were tested to +/-2.5 Nm in flexion-extension, lateral bending, and axial rotation. Range of motion (ROM) was measured (1) in the intact state, (2) with ACDF without plating, (3) after addition of either a bioresorbable or titanium plate, and (4) after 500 cycles of combined flexion-extension and axial torsion. Load sharing was evaluated by applying the same fixed rotation both without and with the plate, and was calculated as the moment resisted by the uninstrumented ACDF expressed as a percentage of the plated ACDF state. No plate failures or graft migration occurred during testing. Compared with the uninstrumented ACDF, bioresorbable plates reduced mean ROM by 49% in flexion-extension and 25% in lateral bending, with very little change in torsion. Titanium plates reduced uninstrumented ACDF ROM by 69% in flexion-extension, 45% in lateral bending, and 27% in torsion. Differences between bioresorbable and titanium plates were significant in flexion-extension and lateral bending. Cyclic loading did not significantly change ROM for either plate. More moment was shared in lateral bending by the spine/graft with bioresorbable plates (78%) compared with titanium plating (63%). Bioresorbable plates contained an intervertebral graft, provided some stabilization, remained intact throughout the simulated immediate postoperative loading, and shared more load with the graft and

  11. Is plate tectonis withstanding the test of time?

    Directory of Open Access Journals (Sweden)

    O. Shields

    1997-06-01

    Full Text Available Since the theory of plate tectonics was first proposed thirty years ago, some problems have arisen in its practical application. These call into question its fundamental assumptions of horizontal plate motion, hotspot fixity, true polar wander, Panthalassa, and the Earth’s constant size while leaving seafloor spreading and subduction intact. A rapidity expanding earth solves these problems and privides an alternative viewpoint worth reconsidering.

  12. Nonlinear Vibration of the Cantilever FGM Plate Based on the Third-order Shear Deformation Plate Theory

    Science.gov (United States)

    Hao, Y. X.; Zhang, W.

    2010-05-01

    The present investigation focuses on the research of the nonlinear vibration of a cantilevered FGMs rectangular plate subjected to the transversal excitation. Materials properties of the constituents are graded in the thickness direction according to a power law distribution and are assumed to be temperature-dependent and vary along the thickness direction. In the framework of the Reddy's Third-order shear deformation plate theory, the governing equations of motion for the cantilever FGMs rectangular plate are derived by using the Hamilton's principle. The thermal effect due to one-dimensional temperature gradient is included in the analysis. The equations of motion can be reduced two-degree-of-freedom nonlinear system under the external excitations using the Galerkin's method. Using numerical method, the control equations are analyzed to obtain the response curves. A detailed parametric study is conducted to show the influences of the material properties on dynamic responses of the nonlinear vibration of the cantilever FGM plate.

  13. Create Your Plate

    Medline Plus

    Full Text Available ... Monthly In Memory In Honor Become a Member En Español Type 1 Type 2 About Us Online ... Print Page Text Size: A A A Listen En Español Create Your Plate Create Your Plate is ...

  14. Create Your Plate

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    Full Text Available ... Diabetes Meal Plans Create Your Plate Gluten Free Diets Meal Planning for Vegetarian Diets Cook with Heart-Healthy Foods Holiday Meal Planning ... Planning Meals Diabetes Meal Plans and a Healthy Diet Create Your Plate Meal Planning for Vegetarian Diets ...

  15. Create Your Plate

    Medline Plus

    Full Text Available ... Your Plate Gluten Free Diets Meal Planning for Vegetarian Diets Cook with Heart-Healthy Foods Holiday Meal Planning What Can I Eat? Making ... Forecast® magazine: wcie-meal-planning, . In this ... Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook ...

  16. Create Your Plate

    Medline Plus

    Full Text Available ... In Memory In Honor Become a Member En Español Type 1 Type 2 About Us Online Community ... Page Text Size: A A A Listen En Español Create Your Plate Create Your Plate is a ...

  17. Growth Plate Injuries

    Science.gov (United States)

    ... cause any lasting problems for your child or teen. Growth plates are areas of growing tissues that cause ... are replaced by solid bone. Who gets them? Growth plate injuries happen to children and teens. This injury happens twice as often in boys ...

  18. Create Your Plate

    Medline Plus

    Full Text Available ... Planning Meals Diabetes Meal Plans Create Your Plate Gluten Free Diets Meal Planning for Vegetarian Diets Cook with Heart- ... Create Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook with Heart-Healthy Foods ...

  19. Nonlinear vibration of thick FGM plates on elastic foundation subjected to thermal and mechanical loads using the first-order shear deformation plate theory

    Directory of Open Access Journals (Sweden)

    Nguyen Dinh Duc

    2015-12-01

    Full Text Available This paper presents an analytical approach to investigate the nonlinear dynamic response and vibration of thick functionally graded material (FGM plates using both of the first-order shear deformation plate theory and stress function with full motion equations (not using Volmir’s assumptions. The FGM plate is assumed to rest on elastic foundation and subjected to mechanical, thermal, and damping loads. Numerical results for dynamic response of the FGM plate are obtained by Runge–Kutta method. The results show the material properties, the elastic foundations, mechanical and thermal loads on the nonlinear dynamic response of functionally graded plates.

  20. The Southern Proper Motion Program. IV. The SPM4 Catalog

    Science.gov (United States)

    Girard, Terrence M.; van Altena, William F.; Zacharias, Norbert; Vieira, Katherine; Casetti-Dinescu, Dana I.; Castillo, Danilo; Herrera, David; Lee, Young Sun; Beers, Timothy C.; Monet, David G.; López, Carlos E.

    2011-07-01

    We present the fourth installment of the Yale/San Juan Southern Proper Motion Catalog, SPM4. The SPM4 contains absolute proper motions, celestial coordinates, and B, V photometry for over 103 million stars and galaxies between the south celestial pole and -20° declination. The catalog is roughly complete to V = 17.5 and is based on photographic and CCD observations taken with the Yale Southern Observatory's double astrograph at Cesco Observatory in El Leoncito, Argentina. The proper-motion precision, for well-measured stars, is estimated to be 2-3 mas yr-1, depending on the type of second-epoch material. At the bright end, proper motions are on the International Celestial Reference System by way of Hipparcos Catalog stars, while the faint end is anchored to the inertial system using external galaxies. Systematic uncertainties in the absolute proper motions are on the order of 1 mas yr-1.

  1. The Absolute Normal Scores Test for Symmetry

    Science.gov (United States)

    Penfield, Douglas A.; Sachdeva, Darshan

    1976-01-01

    The absolute normal scores test is described as a test for the symmetry of a distribution of scores about a location parameter. The test is compared to the sign test and the Wilcoxon test as an alternative to the "t"-test. (Editor/RK)

  2. The Theory of Absolute Reaction Rates

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 17; Issue 7. The Theory of Absolute Reaction Rates. Henry Eyring. Classics Volume 17 Issue 7 July 2012 pp 704-711. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/017/07/0704-0711. Author Affiliations.

  3. 49 CFR 236.709 - Block, absolute.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Block, absolute. 236.709 Section 236.709 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RULES, STANDARDS, AND INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION...

  4. Thin-film magnetoresistive absolute position detector

    NARCIS (Netherlands)

    Groenland, J.P.J.

    1990-01-01

    The subject of this thesis is the investigation of a digital absolute posi- tion-detection system, which is based on a position-information carrier (i.e. a magnetic tape) with one single code track on the one hand, and an array of magnetoresistive sensors for the detection of the information on the

  5. Det demokratiske argument for absolut ytringsfrihed

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    Artiklen diskuterer den påstand, at absolut ytringsfrihed er en nødvendig forudsætning for demokratisk legitimitet med udgangspunkt i en rekonstruktion af et argument fremsat af Ronald Dworkin. Spørgsmålet er, hvorfor ytringsfrihed skulle være en forudsætning for demokratisk legitimitet, og hvorf...

  6. Absolute Distance Measurements with Tunable Semiconductor Laser

    Czech Academy of Sciences Publication Activity Database

    Mikel, Břetislav; Číp, Ondřej; Lazar, Josef

    T118, - (2005), s. 41-44 ISSN 0031-8949 R&D Projects: GA AV ČR(CZ) IAB2065001 Keywords : tunable laser * absolute interferometer Subject RIV: BH - Optics, Masers, Lasers Impact factor: 0.661, year: 2004

  7. Stimulus Probability Effects in Absolute Identification

    Science.gov (United States)

    Kent, Christopher; Lamberts, Koen

    2016-01-01

    This study investigated the effect of stimulus presentation probability on accuracy and response times in an absolute identification task. Three schedules of presentation were used to investigate the interaction between presentation probability and stimulus position within the set. Data from individual participants indicated strong effects of…

  8. systemic complications following absolute alcohol embolisation of ...

    African Journals Online (AJOL)

    of the superficial temporal (STA), middle meningeal. (MMA) and occipital ... external jugular vein. Absolute alcohol was injected into the feeder artery using the intermittent pulsed spray technique in aliquots of 1 ml. A total of 55 ml of alcohol was injected. ... cells, vessel wall necrosis resulting in thrombosis and permanent ...

  9. On the absolute measure of Beta activities

    International Nuclear Information System (INIS)

    Sanchez del Rio, C.; Jimenez Reynaldo, O.; Rodriguez Mayquez, E.

    1956-01-01

    A new method for absolute beta counting of solid samples is given. The mea surements is made with an inside Geiger-Muller tube of new construction. The backscattering correction when using an infinite thick mounting is discussed and results for different materials given. (Author)

  10. Absolute tightness: the chemists hesitate to invest

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    The safety requirements of industries as nuclear plants and the strengthening of regulations in the field of environment (more particularly those related to volatile organic compounds) have lead the manufacturers to build absolute tightness pumps. But these equipments do not answer all the problems and represent a high investment cost. In consequence, the chemists hesitate to invest. (O.L.)

  11. Nonlinear oscillations, bifurcations and chaos of functionally graded materials plate

    Science.gov (United States)

    Hao, Y. X.; Chen, L. H.; Zhang, W.; Lei, J. G.

    2008-05-01

    An analysis on the nonlinear dynamics of a simply supported functionally graded materials (FGMs) rectangular plate subjected to the transversal and in-plane excitations is presented in a thermal environment for the first time. Material properties are assumed to be temperature dependent. Based on Reddy's third-order plate theory, the nonlinear governing equations of motion for the FGM plates are derived using Hamilton's principle. Galerkin's method is utilized to discretize the governing partial equations to a two-degree-of-freedom nonlinear system including the quadratic and cubic nonlinear terms under combined parametric and external excitations. The resonant case considered here is 1:1 internal resonance and principal parametric resonance. The asymptotic perturbation method is utilized to obtain four-dimensional nonlinear averaged equation. The numerical method is used to find the nonlinear dynamic responses of the FGM rectangular plate. It was found that periodic, quasi-periodic solutions and chaotic motions exist for the FGM rectangular plates under certain conditions. It is believed that the forcing excitations f1 and f2 can change the form of motions for the FGM rectangular plate.

  12. Plate tectonics in the late Paleozoic

    Directory of Open Access Journals (Sweden)

    Mathew Domeier

    2014-05-01

    Full Text Available As the chronicle of plate motions through time, paleogeography is fundamental to our understanding of plate tectonics and its role in shaping the geology of the present-day. To properly appreciate the history of tectonics—and its influence on the deep Earth and climate—it is imperative to seek an accurate and global model of paleogeography. However, owing to the incessant loss of oceanic lithosphere through subduction, the paleogeographic reconstruction of ‘full-plates’ (including oceanic lithosphere becomes increasingly challenging with age. Prior to 150 Ma ∼60% of the lithosphere is missing and reconstructions are developed without explicit regard for oceanic lithosphere or plate tectonic principles; in effect, reflecting the earlier mobilistic paradigm of continental drift. Although these ‘continental’ reconstructions have been immensely useful, the next-generation of mantle models requires global plate kinematic descriptions with full-plate reconstructions. Moreover, in disregarding (or only loosely applying plate tectonic rules, continental reconstructions fail to take advantage of a wealth of additional information in the form of practical constraints. Following a series of new developments, both in geodynamic theory and analytical tools, it is now feasible to construct full-plate models that lend themselves to testing by the wider Earth-science community. Such a model is presented here for the late Paleozoic (410–250 Ma together with a review of the underlying data. Although we expect this model to be particularly useful for numerical mantle modeling, we hope that it will also serve as a general framework for understanding late Paleozoic tectonics, one on which future improvements can be built and further tested.

  13. Auditory motion capturing ambiguous visual motion

    Directory of Open Access Journals (Sweden)

    Arjen eAlink

    2012-01-01

    Full Text Available In this study, it is demonstrated that moving sounds have an effect on the direction in which one sees visual stimuli move. During the main experiment sounds were presented consecutively at four speaker locations inducing left- or rightwards auditory apparent motion. On the path of auditory apparent motion, visual apparent motion stimuli were presented with a high degree of directional ambiguity. The main outcome of this experiment is that our participants perceived visual apparent motion stimuli that were ambiguous (equally likely to be perceived as moving left- or rightwards more often as moving in the same direction than in the opposite direction of auditory apparent motion. During the control experiment we replicated this finding and found no effect of sound motion direction on eye movements. This indicates that auditory motion can capture our visual motion percept when visual motion direction is insufficiently determinate without affecting eye movements.

  14. Auditory Motion Elicits a Visual Motion Aftereffect.

    Science.gov (United States)

    Berger, Christopher C; Ehrsson, H Henrik

    2016-01-01

    The visual motion aftereffect is a visual illusion in which exposure to continuous motion in one direction leads to a subsequent illusion of visual motion in the opposite direction. Previous findings have been mixed with regard to whether this visual illusion can be induced cross-modally by auditory stimuli. Based on research on multisensory perception demonstrating the profound influence auditory perception can have on the interpretation and perceived motion of visual stimuli, we hypothesized that exposure to auditory stimuli with strong directional motion cues should induce a visual motion aftereffect. Here, we demonstrate that horizontally moving auditory stimuli induced a significant visual motion aftereffect-an effect that was driven primarily by a change in visual motion perception following exposure to leftward moving auditory stimuli. This finding is consistent with the notion that visual and auditory motion perception rely on at least partially overlapping neural substrates.

  15. Lohse's historic plate archive

    Science.gov (United States)

    Tsvetkov, M.; Tsvetkova, K.; Richter, G.; Scholz, G.; Böhm, P.

    The description and the analysis of Oswald Lohse's astrophotographic plates, collected at the Astrophysical Observatory Potsdam in the period 1879 - 1889, are presented. 67 plates of the archive, taken with the greatest instrument of the observatory at that time - the refractor (D = 0.30 m, F = 5.40 m, scale = 38''/mm) and with the second heliographic objective (D = 0.13 m, F = 1.36 m, scale = 152''/mm) - - survived two world wars in relative good condition. The plate emulsions are from different manufacturers in the beginning of astrophotography (Gädicke, Schleussner, Beernaert, etc.). The sizes of the plates are usually 9x12 cm2, which corresponds to fields of 1.2deg and 5deg respectively for each instrument mentioned above. The average limiting magnitude is 13.0(pg). Besides of the plates received for technical experiments (work on photographic processes, testing of new instruments and methods of observations), the scientific observations follow programs for studies of planet surfaces, bright stars, some double stars, stellar clusters and nebulous objects. Lohse's archive is included into the Wide Field Plate Database (http://www.skyarchive.org) as the oldest systematic one, covering the fields of Orion (M42/43), Pleiades, h & chi Persei, M37, M3, M11, M13, M92, M31, etc. With the PDS 2020 GM+ microdensitometer of Münster University 10 archive plates were digitized.

  16. The Absolute Shielding Constants of Heavy Nuclei: Resolving the Enigma of the (119)Sn Absolute Shielding.

    Science.gov (United States)

    Malkin, Elena; Komorovsky, Stanislav; Repisky, Michal; Demissie, Taye B; Ruud, Kenneth

    2013-02-07

    We demonstrate that the apparent disagreement between experimental determinations and four-component relativistic calculations of the absolute shielding constants of heavy nuclei is due to the breakdown of the commonly assumed relation between the electronic contribution to the nuclear spin-rotation constants and the paramagnetic contribution to the NMR shielding constants. We demonstrate that this breakdown has significant consequences for the absolute shielding constant of (119)Sn, leading to errors of about 1000 ppm. As a consequence, we expect that many absolute shielding constants of heavy nuclei will be in need of revision.

  17. An Absolute Valve for the ITER Neutral Beam Injector

    International Nuclear Information System (INIS)

    Jones, Ch.; Chuilon, B.; Michael, W.

    2006-01-01

    In the ITER reference design a fast shutter was included to limit tritium migration into the beamline vacuum enclosures. The need was recently identified to extend the functionality of the fast shutter to that of an absolute valve in order to facilitate injector maintenance procedures and to satisfy safety requirements in case of an in-vessel loss of coolant event. Three concepts have been examined satisfying the ITER requirements for speed of actuation, sealing performance over the required lifetime, and pressure differential in fault scenarios, namely: a rectangular closure section; a circular cross section; and a rotary JET-type valve. The rectangular section represents the most efficient usage of the available space envelope and leads to a minimum-mass system, although it requires greater total force for a given load per unit length of seal. However, a metallic seal of the '' hard/hard '' type, where the seal relies on the elastic properties of the material and does not utilise any type of spring device, can provide the required seal performance with typical loading of 200 kg/cm. The conceptual design of the proposed absolute valve will be presented. The aperture dimensions are 1.45 m high by 0.6 m wide, with minimum achievable leak rate of 1 · 10 -9 mbarl/s and maximum pressure differential of 3 bar across the valve. Sealing force is provided using two seal plates, linked by a 3 mm thick ' omega ' diaphragm, by pressurisation of the interspace to 8 bar; this allows for a relative movement of the plates of 2 mm. Movement of the device perpendicular to the beam direction is carried out using a novel magnetic drive in order to transmit the motive force across the vacuum boundary, similar to that demonstrated on a test-rig in an earlier study. The conceptual design includes provision of all the services such as pneumatics and water cooling to cope with the heat loads from neutral beams in quasi steady-state operation and from the ITER plasma. A future programme

  18. Modal radiation patterns of baffled circular plates and membranes

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lehrmann; Hansen, Ole; Thomsen, Erik Vilain

    2014-01-01

    The far field velocity potential and radiation pattern of baffled circular plates and membranes are found analytically using the full set of modal velocity profiles derived from the corresponding equation of motion. The derivation is valid for a plate or membrane subjected to an external excitation...... of a plate with clamped, simply supported, and free edge boundary conditions as well as for the membrane. For all non-axisymmetric modes, the velocity potential along the axis of the radiator is found to be strictly zero. In the long wavelength limit, the radiationpattern of all axisymmetric modes approaches...

  19. Human sensitivity to vertical self-motion.

    Science.gov (United States)

    Nesti, Alessandro; Barnett-Cowan, Michael; Macneilage, Paul R; Bülthoff, Heinrich H

    2014-01-01

    Perceiving vertical self-motion is crucial for maintaining balance as well as for controlling an aircraft. Whereas heave absolute thresholds have been exhaustively studied, little work has been done in investigating how vertical sensitivity depends on motion intensity (i.e., differential thresholds). Here we measure human sensitivity for 1-Hz sinusoidal accelerations for 10 participants in darkness. Absolute and differential thresholds are measured for upward and downward translations independently at 5 different peak amplitudes ranging from 0 to 2 m/s(2). Overall vertical differential thresholds are higher than horizontal differential thresholds found in the literature. Psychometric functions are fit in linear and logarithmic space, with goodness of fit being similar in both cases. Differential thresholds are higher for upward as compared to downward motion and increase with stimulus intensity following a trend best described by two power laws. The power laws' exponents of 0.60 and 0.42 for upward and downward motion, respectively, deviate from Weber's Law in that thresholds increase less than expected at high stimulus intensity. We speculate that increased sensitivity at high accelerations and greater sensitivity to downward than upward self-motion may reflect adaptations to avoid falling.

  20. High loading uranium plate

    International Nuclear Information System (INIS)

    Wiencek, T.C.; Domagala, R.F.; Thresh, H.R.

    1990-01-01

    Two embodiments of a high uranium fuel plate are disclosed which contain a meat comprising structured uranium compound confined between a pari of diffusion bonded ductile metal cladding plates uniformly covering the meat, the meat hiving a uniform high fuel loading comprising a content of uranium compound greater than about 45 Vol. % at a porosity not greater than about 10 Vol. %. In a first embodiment, the meat is a plurality of parallel wires of uranium compound. In a second embodiment, the meat is a dispersion compact containing uranium compound. The fuel plates are fabricated by a hot isostatic pressing process

  1. Motion control report

    CERN Document Server

    2013-01-01

    Please note this is a short discount publication. In today's manufacturing environment, Motion Control plays a major role in virtually every project.The Motion Control Report provides a comprehensive overview of the technology of Motion Control:* Design Considerations* Technologies* Methods to Control Motion* Examples of Motion Control in Systems* A Detailed Vendors List

  2. From Hubble's NGSL to Absolute Fluxes

    Science.gov (United States)

    Heap, Sara R.; Lindler, Don

    2012-01-01

    Hubble's Next Generation Spectral Library (NGSL) consists of R-l000 spectra of 374 stars of assorted temperature, gravity, and metallicity. Each spectrum covers the wavelength range, 0.18-1.00 microns. The library can be viewed and/or downloaded from the website, http://archive.stsci.edu/prepds/stisngsll. Stars in the NGSL are now being used as absolute flux standards at ground-based observatories. However, the uncertainty in the absolute flux is about 2%, which does not meet the requirements of dark-energy surveys. We are therefore developing an observing procedure that should yield fluxes with uncertainties less than 1 % and will take part in an HST proposal to observe up to 15 stars using this new procedure.

  3. Trapped individual ion at absolute zero temperature

    Science.gov (United States)

    Yu, Nan; Dehmelt, Hans; Nagourney, Warren

    1989-01-01

    Laser cooling and ion trapping have progressed to such an extent that one can now speak of realizing a confined atom at absolute zero temperature. In this short publication, we analyze an experiment toward such realization using a single Ba+ ion in a miniature rf trap. The Ba+ ion is first laser-cooled to the limit where the ion spends most of its time in the zero-point energy state. Then a test sequence allows one to verify whether or not the ion is actually in its zero-point state. The test sequence may also serve as a device for state selection of an atom at absolute zero temperature. PMID:16594054

  4. Interpolation of uniformly absolutely continuous operators

    Czech Academy of Sciences Publication Activity Database

    Cobos, F.; Gogatishvili, Amiran; Opic, B.; Pick, L.

    2013-01-01

    Roč. 286, 5-6 (2013), s. 579-599 ISSN 0025-584X R&D Projects: GA ČR GA201/08/0383 Institutional support: RVO:67985840 Keywords : uniformly absolutely continuous operators * interpolation * type of an interpolation method Subject RIV: BA - General Mathematics Impact factor: 0.658, year: 2013 http://onlinelibrary.wiley.com/doi/10.1002/ mana .201100205/full

  5. Absolute spectrophotometry of the β Lyr

    International Nuclear Information System (INIS)

    Burnashev, V.I.; Skul'skij, M.Yu.

    1978-01-01

    In 1974 an absolute spectrophotometry of β Lyr was performed with the scanning spectrophotometer in the 3300-7400 A range. The energy distribution in the β Lyr spectrum is obtained. The β Lyr model is proposed. It is shown, that the continuous spectrum of the β Lyr radiation can be presented by the total radiation of the B8 3 and A5 3 two stars and of the gaseous envelope with Te =20000 K

  6. Benzofuranoid and bicyclooctanoid neolignans:absolute configuration

    International Nuclear Information System (INIS)

    Alvarenga, M.A. de; Giesbrecht, A.M.; Gottlieb, O.R.; Yoshida, M.

    1977-01-01

    The naturally occuring benzofuranoid and bicyclo (3,2,1) octanoid neolignans have their relative configurations established by 1 H and 13 C NMR, inclusively with aid of the solvent shift technique. Interconversion of the benzofuranoid type compounds, as well as for a benzofuranoid to a bicyclooctanoid derivate, make ORD correlations, ultimately with (2S, 3S) - and (2R,3R)-2,3- dihydrobenzofurans, possible, and led to the absolute configurations of both series of neolignans [pt

  7. Create Your Plate

    Medline Plus

    Full Text Available ... managing diabetes and losing weight. Creating your plate lets you still choose the foods you want, but ... you have an easy portion control solution that works. Last Reviewed: October 8, 2015 Last Edited: September ...

  8. What's On Your Plate?

    Science.gov (United States)

    ... what these nutrients do in your body and what foods they are found in. Plans for Healthy Living ... food choices. Get more nutrition information online with What's On Your Plate? Smart Food Choices for Healthy Aging from the National Institute ...

  9. Create Your Plate

    Medline Plus

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  10. Create Your Plate

    Medline Plus

    Full Text Available ... Count Glycemic Index Low-Calorie Sweeteners Sugar and Desserts Fitness Exercise & Type 1 Diabetes Get Started Safely ... blood glucose levels and lose weight. With this method, you fill your plate with more non-starchy ...

  11. Create Your Plate

    Medline Plus

    Full Text Available ... Edited: September 14, 2016 Articles from Diabetes Forecast® magazine: wcie-meal-planning, . In this section Food Planning Meals Diabetes Meal Plans and a Healthy Diet Create Your Plate Meal Planning for Vegetarian Diets Gluten ...

  12. Create Your Plate

    Medline Plus

    Full Text Available ... Children and Type 2 Diabetes Know Your Rights Employment Discrimination Health Care Professionals Law Enforcement Driver's License ... blood glucose levels and lose weight. With this method, you fill your plate with more non-starchy ...

  13. Humvee Armor Plate Drilling

    National Research Council Canada - National Science Library

    2004-01-01

    When drilling holes in hard steel plate used in up-armor kits for Humvee light trucks, the Anniston Army Depot, Anniston, Alabama, requested the assistance of the National Center for Defense Manufacturing and Machining (NCDMM...

  14. Create Your Plate

    Medline Plus

    Full Text Available ... one side, cut it again so you will have three sections on your plate. Fill the largest ... home, the office, or somewhere in between, you have an easy portion control solution that works. Last ...

  15. How would surround vehicles move? A Unified Framework for Maneuver Classification and Motion Prediction

    OpenAIRE

    Deo, Nachiket; Rangesh, Akshay; Trivedi, Mohan M.

    2018-01-01

    Reliable prediction of surround vehicle motion is a critical requirement for path planning for autonomous vehicles. In this paper we propose a unified framework for surround vehicle maneuver classification and motion prediction that exploits multiple cues, namely, the estimated motion of vehicles, an understanding of typical motion patterns of freeway traffic and inter-vehicle interaction. We report our results in terms of maneuver classification accuracy and mean and median absolute error of...

  16. Neutron imaging plates

    International Nuclear Information System (INIS)

    Niimura, Nobuo

    1995-01-01

    Imaging plates have been used in the field of medical diagnosis since long ago, but their usefulness was verified as the two-dimensional detector for analyzing the X-ray crystalline structure of high bio molecules like protein, and they have contributed to the remarkable progress in this field. The great contribution is due to the excellent features, such as the detection efficiency of about 100%, the positional resolution smaller than 0.2 mm, the dynamic range of five digits, and the area of several hundreds mm square. The neutron imaging plates have not yet obtained the sufficient results. It was planned to construct the neutron diffractometer for biological matters, and to put imaging plate neutron detectors (IP-ND) to practical use as the detector. The research on the development of IP-NDs was carried out, and the IPp-NDs having the performance comparable with that for X-ray were able to be produced. Imaging plates are the integral type two-dimensional radiation detector using photostimulated luminescence matters, and their principle is explained. As to neutron imaging plates, the converter, neutron detection efficiency and the flight of secondary particles in photo-stimulated luminescence matters are described. As for the present state of development of neutron imaging plates, the IP-NDs made for trial, the dynamic range, the positional resolution, the detection efficiency and the kinds of converters, and the application of IP-NDs are reported. (K.I.)

  17. Dizziness and Motion Sickness

    Science.gov (United States)

    ... You Dizziness and Motion Sickness Dizziness and Motion Sickness Patient Health Information News media interested in covering the latest ... medications Remember: Most cases of dizziness and motion sickness are ... Health Home Copyright © 2018 American Academy of Otolaryngology–Head ...

  18. Flow structures generated by elongated plates settling in a water column

    DEFF Research Database (Denmark)

    Sørensen, Henrik; Jensen, Anna Lyhne; Hærvig, Jakob

    angle of 15° in a 0.60 m x 0.30 m  0.35 m (LBH) glass container filled with water. Continuous Particle Image Velocimetry is used to analyse both the velocity field of the continuous phase and the motion of the plates. The experiments show a well-defined oscillating motion of the plate. A stall occurs...

  19. From Plate Tectonic to Continental Dynamics

    Science.gov (United States)

    Molnar, P. H.

    2017-12-01

    By the early 1970s, the basics of plate tectonics were known. Although much understanding remained to be gained, as a topic of research, plate tectonics no longer defined the forefront of earth science. Not only had it become a foundation on which to build, but also the methods used to reveal it became tools to take in new directions. For me as a seismologist studying earthquakes and active processes, the deformation of continents offered an obvious topic to pursue. Obviously examining the deformation of continents and ignoring the widespread geologic evidence of both ongoing and finite deformation of crust would be stupid. I was blessed with the opportunity to learn from and collaborate with two of the best, Paul Tapponnier and Clark Burchfiel. Continental deformation differed from plate tectonics both because deformation was widespread but more importantly because crust shortens (extends) horizontally and thickens (thins), processes that can be ignored where plate tectonics - the relative motion of rigid plates - occurs. Where a plate boundary passes into a continent, not only must the forces that move plates do work against friction or other dissipative processes, but where high terrain is created, they must also do work against gravity, to create gravitational potential energy in high terrain. Peter Bird and Kenneth Piper and Philip England and Dan McKenzie showed that a two-dimensional thin viscous sheet with vertically averaged properties enabled both sources of resistance to be included without introducing excessive complexity and to be scaled by one dimensionless number, what the latter pair called the Argand number. Increasingly over the past thirty years, emphasis has shifted toward the role played by the mantle lithosphere, because of both its likely strength and its negative buoyancy, which makes it gravitationally unstable. Despite progress since realizing that rigid plates (the essence of plate tectonics) provides a poor description of continental

  20. Magneto-elastic dynamics and bifurcation of rotating annular plate*

    International Nuclear Information System (INIS)

    Hu Yu-Da; Piao Jiang-Min; Li Wen-Qiang

    2017-01-01

    In this paper, magneto-elastic dynamic behavior, bifurcation, and chaos of a rotating annular thin plate with various boundary conditions are investigated. Based on the thin plate theory and the Maxwell equations, the magneto-elastic dynamic equations of rotating annular plate are derived by means of Hamilton’s principle. Bessel function as a mode shape function and the Galerkin method are used to achieve the transverse vibration differential equation of the rotating annular plate with different boundary conditions. By numerical analysis, the bifurcation diagrams with magnetic induction, amplitude and frequency of transverse excitation force as the control parameters are respectively plotted under different boundary conditions such as clamped supported sides, simply supported sides, and clamped-one-side combined with simply-anotherside. Poincaré maps, time history charts, power spectrum charts, and phase diagrams are obtained under certain conditions, and the influence of the bifurcation parameters on the bifurcation and chaos of the system is discussed. The results show that the motion of the system is a complicated and repeated process from multi-periodic motion to quasi-period motion to chaotic motion, which is accompanied by intermittent chaos, when the bifurcation parameters change. If the amplitude of transverse excitation force is bigger or magnetic induction intensity is smaller or boundary constraints level is lower, the system can be more prone to chaos. (paper)

  1. Automatic solar image motion measurements. [electronic disk flux monitoring

    Science.gov (United States)

    Colgate, S. A.; Moore, E. P.

    1975-01-01

    The solar seeing image motion has been monitored electronically and absolutely with a 25 cm telescope at three sites along the ridge at the southern end of the Magdalena Mountains west of Socorro, New Mexico. The uncorrelated component of the variations of the optical flux from two points at opposite limbs of the solar disk was continually monitored in 3 frequencies centered at 0.3, 3 and 30 Hz. The frequency band of maximum signal centered at 3 Hz showed the average absolute value of image motion to be somewhat less than 2sec. The observer estimates of combined blurring and image motion were well correlated with electronically measured image motion, but the observer estimates gave a factor 2 larger value.

  2. Achieving Climate Change Absolute Accuracy in Orbit

    Science.gov (United States)

    Wielicki, Bruce A.; Young, D. F.; Mlynczak, M. G.; Thome, K. J; Leroy, S.; Corliss, J.; Anderson, J. G.; Ao, C. O.; Bantges, R.; Best, F.; hide

    2013-01-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission will provide a calibration laboratory in orbit for the purpose of accurately measuring and attributing climate change. CLARREO measurements establish new climate change benchmarks with high absolute radiometric accuracy and high statistical confidence across a wide range of essential climate variables. CLARREO's inherently high absolute accuracy will be verified and traceable on orbit to Système Internationale (SI) units. The benchmarks established by CLARREO will be critical for assessing changes in the Earth system and climate model predictive capabilities for decades into the future as society works to meet the challenge of optimizing strategies for mitigating and adapting to climate change. The CLARREO benchmarks are derived from measurements of the Earth's thermal infrared spectrum (5-50 micron), the spectrum of solar radiation reflected by the Earth and its atmosphere (320-2300 nm), and radio occultation refractivity from which accurate temperature profiles are derived. The mission has the ability to provide new spectral fingerprints of climate change, as well as to provide the first orbiting radiometer with accuracy sufficient to serve as the reference transfer standard for other space sensors, in essence serving as a "NIST [National Institute of Standards and Technology] in orbit." CLARREO will greatly improve the accuracy and relevance of a wide range of space-borne instruments for decadal climate change. Finally, CLARREO has developed new metrics and methods for determining the accuracy requirements of climate observations for a wide range of climate variables and uncertainty sources. These methods should be useful for improving our understanding of observing requirements for most climate change observations.

  3. Bistability of flight states for heavy falling plates

    Science.gov (United States)

    Lau, Edwin; Huang, Wei-Xi

    2017-11-01

    Interactions of falling flat plates in two-dimensional flows is presented through direct numerical simulation and immersed boundary method. The transition from steady falling to tumbling flight for heavy plates is presented. At steep angles of release, the plates undergo a period of amplitude increasing fluttering motion before developing to tumble. For the same fluid-solid system of Reynolds number Re and moment of inertia I*, shallow angles of release develop to a state of steady falling after a period of diminishing fluttering amplitude. Simulations further construct a mapping of this bistable region. Relationships among Re, I*, and the critical angles of release separating the two flight states are also provided. The inclusion of this finding on the mapping of flight states suggests fluttering motion as a transitional state before the onset of tumble. National Natural Science Foundation of China or NSFC (Grant No. 11322221).

  4. Plasticity, Fracture and Friction in Steady-State Plate Cutting

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup; Wierzbicki, Tomasz

    1997-01-01

    A closed form solution to the problem of steady-state wedge cutting through a ductile metal plate is presented. The considered problem is an idealization of a ship bottom raking process, i.e. a continuous cutting damage of a ship bottom by a hard knife-like rock in a grounding event. A new...... extension of the presented plate model to include more structural members as for example the stiffeners attached to a ship bottom plating. The fracture process is discussed and the model is formulated partly on the basis of the material fracture toughness. The effect of friction and the reaction force...... perpendicular to the direction of motion is derived theoretically in a consistent manner. The perpendicular reaction force is of paramount importance for prediction the structural damage of a ship hull because it governs the vertical ship motion and rock penetration which is strongly coupled with the horizontal...

  5. General Observations of the Time-Dependent Flow Field Around Flat Plates in Free Fall

    DEFF Research Database (Denmark)

    Hærvig, Jakob; Jensen, Anna Lyhne; Pedersen, Marie Cecilie

    2015-01-01

    a six degrees of freedom (6DOF) solver and a dynamic mesh. To validate the simulation, the trajectories of aluminium plates falling in water are recorded by digital camera recordings and compared to the simulation. The simulation is able to calculate the motion of the plate within each time step...

  6. Influence of lateral slab edge distance on plate velocity, trench velocity, and subduction partitioning

    NARCIS (Netherlands)

    Schellart, W. P.; Stegman, D. R.; Farrington, R. J.; Moresi, L.

    2011-01-01

    Subduction of oceanic lithosphere occurs through both trenchward subducting plate motion and trench retreat. We investigate how subducting plate velocity, trench velocity and the partitioning of these two velocity components vary for individual subduction zone segments as a function of proximity to

  7. Absolute Priority for a Vehicle in VANET

    Science.gov (United States)

    Shirani, Rostam; Hendessi, Faramarz; Montazeri, Mohammad Ali; Sheikh Zefreh, Mohammad

    In today's world, traffic jams waste hundreds of hours of our life. This causes many researchers try to resolve the problem with the idea of Intelligent Transportation System. For some applications like a travelling ambulance, it is important to reduce delay even for a second. In this paper, we propose a completely infrastructure-less approach for finding shortest path and controlling traffic light to provide absolute priority for an emergency vehicle. We use the idea of vehicular ad-hoc networking to reduce the imposed travelling time. Then, we simulate our proposed protocol and compare it with a centrally controlled traffic light system.

  8. Musical Activity Tunes Up Absolute Pitch Ability

    DEFF Research Database (Denmark)

    Dohn, Anders; Garza-Villarreal, Eduardo A.; Ribe, Lars Riisgaard

    2014-01-01

    Absolute pitch (AP) is the ability to identify or produce pitches of musical tones without an external reference. Active AP (i.e., pitch production or pitch adjustment) and passive AP (i.e., pitch identification) are considered to not necessarily coincide, although no study has properly compared...... that APs generally undershoot when adjusting musical pitch, a tendency that decreases when musical activity increases. Finally, APs are less accurate when adjusting the pitch to black key targets than to white key targets. Hence, AP ability may be partly practice-dependent and we speculate that APs may...

  9. Absolute method of measuring magnetic susceptibility

    Science.gov (United States)

    Thorpe, A.; Senftle, F.E.

    1959-01-01

    An absolute method of standardization and measurement of the magnetic susceptibility of small samples is presented which can be applied to most techniques based on the Faraday method. The fact that the susceptibility is a function of the area under the curve of sample displacement versus distance of the magnet from the sample, offers a simple method of measuring the susceptibility without recourse to a standard sample. Typical results on a few substances are compared with reported values, and an error of less than 2% can be achieved. ?? 1959 The American Institute of Physics.

  10. Cadmium plating replacements

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, M.J.; Groshart, E.C.

    1995-03-01

    The Boeing Company has been searching for replacements to cadmium plate. Two alloy plating systems seem close to meeting the needs of a cadmium replacement. The two alloys, zinc-nickel and tin-zinc are from alloy plating baths; both baths are neutral pH. The alloys meet the requirements for salt fog corrosion resistance, and both alloys excel as a paint base. Currently, tests are being performed on standard fasteners to compare zinc-nickel and tin-zinc on threaded hardware where cadmium is heavily used. The Hydrogen embrittlement propensity of the zinc-nickel bath has been tested, and just beginning for the tin-zinc bath. Another area of interest is the electrical properties on aluminum for tin-zinc and will be discussed. The zinc-nickel alloy plating bath is in production in Boeing Commercial Airplane Group for non-critical low strength steels. The outlook is promising that these two coatings will help The Boeing Company significantly reduce its dependence on cadmium plating.

  11. Bending and stretching of plates

    CERN Document Server

    Mansfield, E H; Hemp, W S

    1964-01-01

    The Bending and Stretching of Plates deals with elastic plate theory, particularly on small- and large-deflexion theory. Small-deflexion theory concerns derivation of basic equations, rectangular plates, plates of various shapes, plates whose boundaries are amenable to conformal transformation, plates with variable rigidity, and approximate methods. Large-deflexion theory includes general equations and some exact solutions, approximate methods in large-deflexion theory, asymptotic large-deflexion theories for very thin plates. Asymptotic theories covers membrane theory, tension field theory, a

  12. Is Active Tectonics on Madagascar Consistent with Somalian Plate Kinematics?

    Science.gov (United States)

    Stamps, D. S.; Kreemer, C.; Rajaonarison, T. A.

    2017-12-01

    The East African Rift System (EARS) actively breaks apart the Nubian and Somalian tectonic plates. Madagascar finds itself at the easternmost boundary of the EARS, between the Rovuma block, Lwandle plate, and the Somalian plate. Earthquake focal mechanisms and N-S oriented fault structures on the continental island suggest that Madagascar is experiencing east-west oriented extension. However, some previous plate kinematic studies indicate minor compressional strains across Madagascar. This inconsistency may be due to uncertainties in Somalian plate rotation. Past estimates of the rotation of the Somalian plate suffered from a poor coverage of GPS stations, but some important new stations are now available for a re-evaluation. In this work, we revise the kinematics of the Somalian plate. We first calculate a new GPS velocity solution and perform block kinematic modeling to evaluate the Somalian plate rotation. We then estimate new Somalia-Rovuma and Somalia-Lwandle relative motions across Madagascar and evaluate whether they are consistent with GPS measurements made on the island itself, as well as with other kinematic indicators.

  13. Instability of a cantilevered flexible plate in viscous channel flow

    Science.gov (United States)

    Balint, T. S.; Lucey, A. D.

    2005-10-01

    The stability of a flexible cantilevered plate in viscous channel flow is studied as a representation of the dynamics of the human upper airway. The focus is on instability mechanisms of the soft palate (flexible plate) that cause airway blockage during sleep. We solve the Navier Stokes equations for flow with Reynolds numbers up to 1500 fully coupled with the dynamics of the plate motion solved using finite-differences. The study is 2-D and based upon linearized plate mechanics. When both upper and lower airways are open, the plate is found to lose its stability through a flutter mechanism and a critical Reynolds number exists. When one airway is closed, the plate principally loses its stability through a divergence mechanism and a critical flow speed exists. However, below the divergence-onset flow speed, flutter can exist for low levels of structural damping in the flexible plate. Our results serve to extend understanding of flow-induced instability of cantilevered flexible plates and will ultimately improve the diagnosis and treatment of upper-airway disorders.

  14. Investigation of heave response of the deepwater octagonal FDPSO using various heave plate configurations

    Science.gov (United States)

    Yu, Chenfang; Hu, Zhiqiang; Wang, Shisheng

    2017-12-01

    Heave plates can be employed to control undesirable heave motion amplitudes of the deepwater octagonal Floating, Drilling, Production, Storage, and Offloading (FDPSO) platform. Numerical simulations and model tests were applied to analyze and investigate the hydrodynamic response and the feasibility of the heave plate configurations. The diameter and the depth below the free surface of a single-layer heave plate, as well as the spacing of two-layer heave plates, were considered as the primary variables when studying the effect of heave plates on FDPSO hydrodynamics. The analysis results indicate that the heave plate diameter significantly affects the heave hydrodynamics, and heave performance could be improved with an increased diameter. In addition, increasing the depth below the free surface of a single-layer heave plate does not effectively suppress the heave motion within the range of draft depths tested. The target FDPSO obtained better heave characteristics with increased spacing between the two-layer heave plates. Furthermore, the global performances of the octagonal FDPSO with these typical heave plate configurations were comparatively analyzed. The results indicate that from a hydrodynamic point of view, the single-layer heave plate configuration has an advantage over the two-layer heave plate configuration.

  15. Analysis of absolute flatness testing in sub-stitching interferometer

    Science.gov (United States)

    Jia, Xin; Xu, Fuchao; Xie, Weimin; Xing, Tingwen

    2016-09-01

    Sub-aperture stitching is an effective way to extend the lateral and vertical dynamic range of a conventional interferometer. The test accuracy can be achieved by removing the error of reference surface by the absolute testing method. When the testing accuracy (repeatability and reproducibility) is close to 1nm, in addition to the reference surface, other factors will also affect the measuring accuracy such as environment, zoom magnification, stitching precision, tooling and fixture, the characteristics of optical materials and so on. In the thousand level cleanroom, we establish a good environment system. Long time stability, temperature controlled at 22°+/-0.02°.The humidity and noise are controlled in a certain range. We establish a stitching system in the clean room. The vibration testing system is used to test the vibration. The air pressure testing system is also used. In the motion system, we control the tilt error no more than 4 second to reduce the error. The angle error can be tested by the autocollimator and double grating reading head.

  16. Motion in radiotherapy

    DEFF Research Database (Denmark)

    Korreman, Stine Sofia

    2012-01-01

    This review considers the management of motion in photon radiation therapy. An overview is given of magnitudes and variability of motion of various structures and organs, and how the motion affects images by producing artifacts and blurring. Imaging of motion is described, including 4DCT and 4DPE...

  17. Standardization of the cumulative absolute velocity

    International Nuclear Information System (INIS)

    O'Hara, T.F.; Jacobson, J.P.

    1991-12-01

    EPRI NP-5930, ''A Criterion for Determining Exceedance of the Operating Basis Earthquake,'' was published in July 1988. As defined in that report, the Operating Basis Earthquake (OBE) is exceeded when both a response spectrum parameter and a second damage parameter, referred to as the Cumulative Absolute Velocity (CAV), are exceeded. In the review process of the above report, it was noted that the calculation of CAV could be confounded by time history records of long duration containing low (nondamaging) acceleration. Therefore, it is necessary to standardize the method of calculating CAV to account for record length. This standardized methodology allows consistent comparisons between future CAV calculations and the adjusted CAV threshold value based upon applying the standardized methodology to the data set presented in EPRI NP-5930. The recommended method to standardize the CAV calculation is to window its calculation on a second-by-second basis for a given time history. If the absolute acceleration exceeds 0.025g at any time during each one second interval, the earthquake records used in EPRI NP-5930 have been reanalyzed and the adjusted threshold of damage for CAV was found to be 0.16g-set

  18. Block-classified motion compensation scheme for digital video

    Energy Technology Data Exchange (ETDEWEB)

    Zafar, S. [Argonne National Lab., IL (United States). Mathematics and Computer Science Div.; Zhang, Ya-Qin [David Sarnoff Research Center, Princeton, NJ (United States); Jabbari, B. [George Mason Univ., Fairfax, VA (United States). Dept. of Electrical and Computer Engineering

    1996-03-01

    A novel scheme for block-based motion compensation is introduced in which a block is classified according to the energy that is directly related to the motion activity it represents. This classification allows more flexibility in controlling the bit rate arid the signal-to-noise ratio and results in a reduction in motion search complexity. The method introduced is not dependent on the particular type of motion search algorithm implemented and can thus be used with any method assuming that the underlying matching criteria used is minimum absolute difference. It has been shown that the method is superior to a simple motion compensation algorithm where all blocks are motion compensated regardless of the energy resulting after the displaced difference.

  19. Hotspot motion caused the Hawaiian-Emperor Bend and LLSVPs are not fixed

    Science.gov (United States)

    Tarduno, J. A.; Bono, R. K.

    2017-12-01

    Paleomagnetic study of volcanic rocks remains the gold standard on which to assess hotspot motion, true polar wander and plate motion recorded by oceanic plates. There is remarkable consistency between paleomagnetic results from basaltic lavas recovered by ocean drilling of the Emperor seamounts, and independent predictions of plate circuits. Both reveal greater than 40 mm/yr of southward hotspot motion; thus the dominant reason for the distinct bend morphology the Hawaiian-Emperor track is hotspot motion rather than plate motion. These findings provide the motivation for moving beyond hotspot fixity to understand mantle processes responsible for the observed motions. Global analyses as well as comparisons between the Hawaiian-Emperor and Louisville tracks indicate only a minor (if any) role for true polar wander. Two viable, non-mutually exclusive processes to explain the observed Hawaiian plume motion are: i. plume-ridge and ii plume-LLSVP interaction. Here we further explore these issues by paleomagnetic analyses of basalts from the Cenozoic Hawaiian chain and Late Cretaceous basalts of the southernmost Pacific Plate. The latter yield paleolatitudes consistent with those from the northern Pacific, indicating that long-standing non-dipole fields cannot have been large enough to affect conclusions on hotspot drift. Data from the former suggest some relative motions between the LLSVPs on tens-of-millions of year time scales, which probably record the continual reshaping of these provinces by plume motion in the lower mantle.

  20. Plating on Zircaloy-2

    International Nuclear Information System (INIS)

    Dini, J.W.; Johnson, H.R.; Jones, A.

    1979-03-01

    Zircaloy-2 is a difficult alloy to coat with an adherent electroplate because it easily forms a tenacious oxide film in air and aqueous solutions. Procedures reported in the literature and those developed at SLL for surmounting this problem were investigated. The best results were obtained when specimens were first etched in either an ammonium bifluoride/sulfuric acid or an ammonium bifluoride solution, plated, and then heated at 700 0 C for 1 hour in a constrained condition. Machining threads in the Zircaloy-2 for the purpose of providing sites for mechanical interlocking of the plating also proved satisfactory

  1. NICKEL PLATING PROCESS

    Science.gov (United States)

    Hoover, T.B.; Zava, T.E.

    1959-05-12

    A simplified process is presented for plating nickel by the vapor decomposition of nickel carbonyl. In a preferred form of the invention a solid surface is nickel plated by subjecting the surface to contact with a mixture containing by volume approximately 20% nickel carbonyl vapor, 2% hydrogen sulfide and .l% water vapor or 1% oxygen and the remainder carbon dioxide at room temperature until the desired thickness of nickel is obtained. The advantage of this composition over others is that the normally explosive nickel carbonyl is greatly stabilized.

  2. Forecasting Error Calculation with Mean Absolute Deviation and Mean Absolute Percentage Error

    Science.gov (United States)

    Khair, Ummul; Fahmi, Hasanul; Hakim, Sarudin Al; Rahim, Robbi

    2017-12-01

    Prediction using a forecasting method is one of the most important things for an organization, the selection of appropriate forecasting methods is also important but the percentage error of a method is more important in order for decision makers to adopt the right culture, the use of the Mean Absolute Deviation and Mean Absolute Percentage Error to calculate the percentage of mistakes in the least square method resulted in a percentage of 9.77% and it was decided that the least square method be worked for time series and trend data.

  3. Random vibrations of composite beams and plates

    Science.gov (United States)

    Abdelnaser, Ahmad Shehadeh

    In this study, a generalized modal approach is presented to solve more general vibration problems of composite beams and plates. The coupled systems of partial differential equations, representing the equations of motion, are uncoupled into modal equations by utilizing the eigenfunctions of the system and its adjoint. A method is presented to obtain these eigenfunctions for beams with arbitrary boundary conditions and for plates with Levy-type boundary conditions. The forced vibration solutions obtained by this method are then used to calculate the random response characteristics of beams and plates subjected to spatially and temporally correlated random loads. In the analysis of beams, both symmetric cross-ply and angle-ply configurations have been considered. In the symmetric cross-ply configuration with no torsional loads, of course, the warping effects are absent. The angle-ply case, however, includes torsion-warping effects and coupled bending-torsion motions. A simple displacement field is introduced to reflect warping in the third-order shear deformation theory. In the analysis of plates two configurations of the laminates have also been considered: symmetric cross-ply and antisymmetric angle-ply. At this time, these are the only two configurations which can be solved by the closed-form modal analysis approach for the Levy-type boundary conditions. In both cases of the beams and plates, the numerical results with and without shear deformations are obtained and compared. The result for no shear deformation theory are obtained with the classical lamination theory. The results have also been obtained for the first-order shear deformation theory with a somewhat simpler displacement field which has been commonly used in the past. The numerical results are obtained for the global response quantities such as frequencies, displacements, and crossing rates as well as for the local response quantities such as normal and shear stresses across a cross section. The

  4. Absolute and Relative Time-Consistent Revealed Preferences

    OpenAIRE

    T. DEMUYNCK

    2007-01-01

    We introduce an Absolute (Relative) Time-consistent Axiom of Revealed Preference which characterizes the consistency of a choice function with the property of absolute (relative) time-consistency and impatience. The axiom requires that the absolute (relative) time-consistent and impatient closure of the revealed preference relation does not conflict with the strict revealed preference relation.

  5. Subduction controls the distribution and fragmentation of Earth’s tectonic plates.

    Science.gov (United States)

    Mallard, Claire; Coltice, Nicolas; Seton, Maria; Müller, R Dietmar; Tackley, Paul J

    2016-07-07

    The theory of plate tectonics describes how the surface of Earth is split into an organized jigsaw of seven large plates of similar sizes and a population of smaller plates whose areas follow a fractal distribution. The reconstruction of global tectonics during the past 200 million years suggests that this layout is probably a long-term feature of Earth, but the forces governing it are unknown. Previous studies, primarily based on the statistical properties of plate distributions, were unable to resolve how the size of the plates is determined by the properties of the lithosphere and the underlying mantle convection. Here we demonstrate that the plate layout of Earth is produced by a dynamic feedback between mantle convection and the strength of the lithosphere. Using three-dimensional spherical models of mantle convection that self-consistently produce the plate size–frequency distribution observed for Earth, we show that subduction geometry drives the tectonic fragmentation that generates plates. The spacing between the slabs controls the layout of large plates, and the stresses caused by the bending of trenches break plates into smaller fragments. Our results explain why the fast evolution in small back-arc plates reflects the marked changes in plate motions during times of major reorganizations. Our study opens the way to using convection simulations with plate-like behaviour to unravel how global tectonics and mantle convection are dynamically connected.

  6. Nuclear reactor alignment plate configuration

    Energy Technology Data Exchange (ETDEWEB)

    Altman, David A; Forsyth, David R; Smith, Richard E; Singleton, Norman R

    2014-01-28

    An alignment plate that is attached to a core barrel of a pressurized water reactor and fits within slots within a top plate of a lower core shroud and upper core plate to maintain lateral alignment of the reactor internals. The alignment plate is connected to the core barrel through two vertically-spaced dowel pins that extend from the outside surface of the core barrel through a reinforcement pad and into corresponding holes in the alignment plate. Additionally, threaded fasteners are inserted around the perimeter of the reinforcement pad and into the alignment plate to further secure the alignment plate to the core barrel. A fillet weld also is deposited around the perimeter of the reinforcement pad. To accomodate thermal growth between the alignment plate and the core barrel, a gap is left above, below and at both sides of one of the dowel pins in the alignment plate holes through with the dowel pins pass.

  7. Create Your Plate

    Medline Plus

    Full Text Available ... 1 Type 2 About Us Online Community Meal Planning Sign In Search: Search More Sites Search ≡ Are ... Fitness Home Food MyFoodAdvisor Recipes Association Cookbook Recipes Planning Meals Diabetes Meal Plans Create Your Plate Gluten ...

  8. Create Your Plate

    Medline Plus

    Full Text Available ... Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook with Heart-Healthy Foods donate en -- A Future Without Diabetes - a-future-without-diabetes-2.html A Future Without Diabetes Donate towards research today and your gift will be matched. Donate ...

  9. The Plate Tectonics Project

    Science.gov (United States)

    Hein, Annamae J.

    2011-01-01

    The Plate Tectonics Project is a multiday, inquiry-based unit that facilitates students as self-motivated learners. Reliable Web sites are offered to assist with lessons, and a summative rubric is used to facilitate the holistic nature of the project. After each topic (parts of the Earth, continental drift, etc.) is covered, the students will…

  10. Create Your Plate

    Medline Plus

    Full Text Available ... meal-planning, . In this section Food Planning Meals Diabetes Meal Plans and a Healthy Diet Create Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook with Heart-Healthy Foods donate en -- A Future Without Diabetes - a-future-without-diabetes-1.html A Future ...

  11. Create Your Plate

    Medline Plus

    Full Text Available ... Types of Activity Weight Loss Assess Your Lifestyle Getting Started Food Choices In My Community Home Find Your ... but changes the portion sizes so you are getting larger portions of ... seven steps to get started: Using your dinner plate, put a line down ...

  12. Create Your Plate

    Medline Plus

    Full Text Available ... Create Your Plate is a simple and effective way to manage your blood glucose levels and lose weight. With ... for Donations - ways-to-give-201710-hotelscom.html Ways to Give ... to help prevent and manage diabetes. Ask the Experts: Learn to Live Well ...

  13. Create Your Plate

    Medline Plus

    Full Text Available ... meal-planning, . In this section Food Planning Meals Diabetes Meal Plans and a Healthy Diet Create Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook with Heart-Healthy Foods donate en -- A Future Without Diabetes - a-future-without-diabetes-2.html A Future ...

  14. Create Your Plate

    Medline Plus

    Full Text Available ... Type 1 Type 2 About Us Online Community Meal Planning Sign In Search: Search More Sites Search ≡ ... Home Food MyFoodAdvisor Recipes Association Cookbook Recipes Planning Meals Diabetes Meal Plans Create Your Plate Gluten Free ...

  15. Create Your Plate

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    Full Text Available ... Your Plate Meal Planning for Vegetarian Diets Gluten Free Diets Holiday Meal Planning Cook with Heart-Healthy Foods donate en -- A Future Without Diabetes - a-future-without-diabetes.html A Future Without Diabetes Donate towards research today and your gift will be matched. Donate Today We Can Help - we- ...

  16. Create Your Plate

    Medline Plus

    Full Text Available ... tax-deductible gift today can fund critical diabetes research and support vital diabetes education services that improve the ... way to manage your blood glucose levels and lose weight. With this method, you fill your plate with more non-starchy ...

  17. Plate girders under bending

    NARCIS (Netherlands)

    Abspoel, R.; Dubina, D.; Ungureanu, V.

    2016-01-01

    In a material economy driven plate girder design, the lever arm between the flanges will increase. This leads to higher stiffness and bending moment resistance, but also to an in-crease of the web slenderness. This means that high strength steels can be used leading to a large reduction of the steel

  18. Modal radiation patterns of baffled circular plates and membranes

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lehrmann; Hansen, Ole; Thomsen, Erik Vilain

    2014-01-01

    force, which is used as a sound receiver in any medium or as a sound transmitter in a gaseous medium. A general, concise expression is given for the radiation pattern of any mode of the membrane and the plate with arbitrary boundary conditions. Specific solutions are given for the four special cases......The far field velocity potential and radiation pattern of baffled circular plates and membranes are found analytically using the full set of modal velocity profiles derived from the corresponding equation of motion. The derivation is valid for a plate or membrane subjected to an external excitation...... of a plate with clamped, simply supported, and free edge boundary conditions as well as for the membrane. For all non-axisymmetric modes, the velocity potential along the axis of the radiator is found to be strictly zero. In the long wavelength limit, the radiationpattern of all axisymmetric modes approaches...

  19. Absolute ion hydration enthalpies from absolute hardness and some VBT relationships

    Science.gov (United States)

    Kaya, Savaş; Fernandes de Farias, Robson

    2018-01-01

    In the present work, absolute hydration enthalpies are calculated from ion absolute hardness for a series of +1 and -1 ions. The calculated values are compared with those previously reported (Housecroft, 2017) [2] and relationships between Vm-1/3 and absolute hardness are stablished. The following empirical equations have been derived, for cations and anions, respectively: ΔhydHo = -(9.645 η+ + 245.930) and ΔhydHo = -(64.601 η- + 12.321). In such equations, η+ and η- are the absolute hardness. It is shown that for d block monocations (Cu+, Ag+ and Au+), hydration enthalpy is closely related with Clementi effective nuclear charge by the equation: ΔhydHo = -(9.645 η+ + 245.930) (Zeff/(n - 1)), where n is the main quantum number. Furthermore, is shown that a typical VBT parameter (Vm-1/3) is related with η+ and η- values and so, with the energies of the frontier orbitals, that is, is stablished a direct relationship between a structural parameter available by X-ray data and the energy of atomic/molecular orbitals.

  20. Using global, quantitative models of the coupled plates/mantle system to understand Late Miocene dynamics of the Pacific plate

    Science.gov (United States)

    Stotz, Ingo; Iaffaldano, Giampiero; Rhodri Davies, D.

    2017-04-01

    Knowledge of the evolution of continents, inferred from a variety of geological data, as well as observations of the ocean-floor magnetization pattern provide an increasingly-detailed picture of past and present-day plate motions. These are key to study the evolving balance of shallow- and deep-rooted forces acting upon plates and to unravel the dynamics of the coupled plates/mantle system. Here we focus on the clockwise rotation of the Pacific plate motion relative to the hotspots reference frame between 10 and 5 Ma, which is evidenced by a bend in the Hawaiian sea mount chain (Cox & Engebretson, 1985) as well as by marine magnetic and bathymetric data along the Pacific/Antarctica Ridge (Croon et al., 2008). It has been suggested that such a kinematic change owes to the arrival of the Ontong-Java plateau, the biggest oceanic plateau on the Pacific plate, at the Australia/Pacific subducting margin between 10 and 5 Ma, and to its collision with the Melanesian arc. This could have changed the local buoyancy forces and/or sparked a redistribution of the forces already acting within the Pacific realm, causing the Pacific plate to rotate clockwise. Such hypotheses have never been tested explicitly against the available kinematic reconstructions. We do so by using global numerical models of the coupled plates/mantle system. Our models build on the available codes Terra and Shells. Terra is a global, spherical finite-element code for mantle convection, developed by Baumgardner (1985) and Bunge et al. (1996), and further advanced by Yang (1997; 2000) and Davies et al. (2013), among others. Shells is a thin-sheet, finite-element code for lithosphere dynamics (e.g., Bird, 1998). By merging these two independent models we are able to simulate the rheological behavior of the brittle lithosphere and viscous mantle. We compare the plate velocities output by our models with the available kinematic reconstructions to test the above-mentioned hypotheses, and simulate the impact of

  1. Using Global, Quantitative Models of the Coupled Plates/Mantle System to Understand Late Neogene Dynamics of the Pacific Plate

    Science.gov (United States)

    Stotz, I.; Davies, R.; Iaffaldano, G.

    2016-12-01

    Knowledge of the evolution of continents, inferred from a variety of geological data, as well as observations of the ocean-floor magnetization pattern provide an increasingly-detailed picture of past and present-day plate motions. These are key to study the evolving balance of shallow- and deep-rooted forces acting upon plates and to unravel the dynamics of the coupled plates/mantle system. Here we focus on the clockwise rotation of the Pacific plate motion relative to the hotspots reference frame between 10 and 5 Ma, which is evidenced by a bend in the Hawaiian sea mount chain (Cox & Engebretson, 1985) as well as by marine magnetic and bathymetric data along the Pacific/Antarctica Ridge (Croon et al., 2008). It has been suggested that such a kinematic change owes to the arrival of the Ontong-Java plateau, the biggest oceanic plateau on the Pacific plate, at the Australia/Pacific subducting margin between 10 and 5 Ma, and to its collision with the Melanesian arc. This could have changed the local buoyancy forces and/or sparked a redistribution of the forces already acting within the Pacific realm, causing the Pacific plate to rotate clockwise. Such hypotheses have never been tested explicitly against the available kinematic reconstructions. We do so by using global numerical models of the coupled plates/mantle system. Our models build on the available codes Terra and Shells. Terra is a global, spherical finite-element code for mantle convection, developed by Baumgardner (1985) and Bunge et al. (1996), and further advanced by Yang (1997; 2000) and Davies et al. (2013), among others. Shells is a thin-sheet, finite-element code for lithosphere dynamics (e.g., Bird, 1998). By merging these two independent models we are able to simulate the rheological behavior of the brittle lithosphere and viscous mantle. We compare the plate velocities output by our models with the available kinematic reconstructions to test the above-mentioned hypotheses, and simulate the impact of

  2. Absolute beam current monitoring in endstation c

    International Nuclear Information System (INIS)

    Bochna, C.

    1995-01-01

    The first few experiments at CEBAF require approximately 1% absolute measurements of beam currents expected to range from 10-25μA. This represents errors of 100-250 nA. The initial complement of beam current monitors are of the non intercepting type. CEBAF accelerator division has provided a stripline monitor and a cavity monitor, and the authors have installed an Unser monitor (parametric current transformer or PCT). After calibrating the Unser monitor with a precision current reference, the authors plan to transfer this calibration using CW beam to the stripline monitors and cavity monitors. It is important that this be done fairly rapidly because while the gain of the Unser monitor is quite stable, the offset may drift on the order of .5μA per hour. A summary of what the authors have learned about the linearity, zero drift, and gain drift of each type of current monitor will be presented

  3. How is an absolute democracy possible?

    Directory of Open Access Journals (Sweden)

    Joanna Bednarek

    2011-01-01

    Full Text Available In the last part of the Empire trilogy, Commonwealth, Negri and Hardt ask about the possibility of the self-governance of the multitude. When answering, they argue that absolute democracy, understood as the political articulation of the multitude that does not entail its unification (construction of the people is possible. As Negri states, this way of thinking about political articulation is rooted in the tradition of democratic materialism and constitutes the alternative to the dominant current of modern political philosophy that identifies political power with sovereignty. The multitude organizes itself politically by means of the constitutive power, identical with the ontological creativity or productivity of the multitude. To state the problem of political organization means to state the problem of class composition: political democracy is at the same time economic democracy.

  4. Absolute negative mobility in the anomalous diffusion

    Science.gov (United States)

    Chen, Ruyin; Chen, Chongyang; Nie, Linru

    2017-12-01

    Transport of an inertial Brownian particle driven by the multiplicative Lévy noise was investigated here. Numerical results indicate that: (i) The Lévy noise is able to induce absolute negative mobility (ANM) in the system, while disappearing in the deterministic case; (ii) the ANM can occur in the region of superdiffusion while disappearing in the region of normal diffusion, and the appropriate stable index of the Lévy noise makes the particle move along the opposite direction of the bias force to the maximum degree; (iii) symmetry breaking of the Lévy noise also causes the ANM effect. In addition, the intrinsic physical mechanism and conditions for the ANM to occur are discussed in detail. Our results have the implication that the Lévy noise plays an important role in the occurrence of the ANM phenomenon.

  5. MLU and IPSyn measuring absolute complexity

    Directory of Open Access Journals (Sweden)

    Lea Nieminen

    2009-05-01

    Full Text Available This article compares the results of Mean Length of Utterance (MLU and Index of Productive Syntax (IPSyn with the structural complexity of spontaneous utterances produced by 30-month-old Finnish children in a semi-structured playing situation. The comparison was carried out in order to determine the aspects of structural complexity which can be detected with MLU and IPSyn. This research adopts the frameworks of absolute complexity together with a multidimensional view of utterance structure and, furthermore, applies it through Utterance Analysis (UA. The results of the comparison between the metrics and changes in structural complexity discovered by UA reveal that MLU and IPSyn do function as measures of structural complexity but only if used in close relation to each other. Because they focus on different aspects of utterances, the results of both metrics should be interpreted in relation to one another.DOI: http://dx.doi.org/10.5128/ERYa5.11

  6. WHY DOES LEIBNIZ NEED ABSOLUTE TIME?

    Directory of Open Access Journals (Sweden)

    NICOLÁS VAUGHAN C.

    2007-08-01

    Full Text Available Resumen: En este ensayo pongo en contraposición dos doctrinas conspicuamenteleibnicianas: la doctrina del tiempo relacional e ideal, y la doctrina de la armonía preestablecida. Argumentaré que si todas las substancias están necesariamentecoordinadas, entonces no tiene sentido negar el carácter absoluto y real del tiempo. En la primera sección describiré la concepción newtoniana y clarkeana del tiempo absoluto; en la segunda discutiré la crítica leibniciana a dicha concepción, crítica sobre la que se erige su doctrina relacional e ideal del tiempo; en la tercera sección daré un vistazo a la metafísica monádica madura de Leibniz, haciendo especial énfasis en la doctrina de la armonía preestablecida; finalmente, en la última sección sugeriré la existencia de una tensión irreconciliable entre estas dos doctrinas.Abstract: In this paper I bring together two characteristically Leibnizean doctrines:the doctrine of relational and ideal time, and the doctrine of preestablished harmony. I will argue that, if every substance is necessarily connected with another, then it makes no sense to deny absolute and real time. In the first section, I will describe Newton’s and Clarke’s conception of absolute time; then, in the second section, I will consider Leibniz’s critique of that conception, on which he bases his ideal and relational doctrine of time. In the third section I will look briefly at Leibniz’s mature monadic metaphysics, taking special account of his doctrine of preestablished harmony. In the last section, I will suggest that there is an irreconcilable tension between these two doctrines.

  7. Effect of plate working length on plate stiffness and cyclic fatigue life in a cadaveric femoral fracture gap model stabilized with a 12-hole 2.4 mm locking compression plate.

    Science.gov (United States)

    Chao, Peini; Conrad, Bryan P; Lewis, Daniel D; Horodyski, MaryBeth; Pozzi, Antonio

    2013-06-24

    There are several factors that can affect the fatigue life of a bone plate, including the mechanical properties of the plate and the complexity of the fracture. The position of the screws can influence construct stiffness, plate strain and cyclic fatigue of the implants. Studies have not investigated these variables in implants utilized for long bone fracture fixation in dogs and cats. The purpose of the present study was to evaluate the effect of plate working length on construct stiffness, gap motion and resistance to cyclic fatigue of dog femora with a simulated fracture gap stabilized using a 12-hole 2.4 mm locking compression plates (LCP). Femora were plated with 12-hole 2.4 mm LCP using 2 screws per fracture segment (long working length group) or with 12-hole 2.4 mm LCP using 5 screws per fracture segment (a short working length group). Construct stiffness did not differ significantly between stabilization techniques. Implant failure did not occur in any of the plated femora during cycling. Mean ± SD yield load at failure in the short plate working length group was significantly higher than in the long plate working length group. In a femoral fracture gap model stabilized with a 2.4 mm LCP applied in contact with the bone, plate working length had no effect on stiffness, gap motion and resistance to fatigue. The short plate working length constructs failed at higher loads; however, yield loads for both the short and long plate working length constructs were within physiologic range.

  8. The Arabia-India plate boundary unveiled

    Science.gov (United States)

    Fournier, M.; Chamot-Rooke, N. R.; Rodriguez, M.; Petit, C.; Huchon, P.; Beslier, M.; Hazard, B.

    2009-12-01

    Since the advent of Plate Tectonics, tectonic plate boundaries were explored on land as at sea for search of active faults where the destructive energy of earthquakes is released. Yet, some plate boundaries, less active or considered as less dangerous to humankind, escaped general attention and remained unknown to a large extent. Among them, the boundary between two major tectonic plates: Arabia and India. The Arabia-India motion is currently accommodated along the Owen Fracture Zone (OFZ) in the NW Indian Ocean, which connects the spreading centers of the Sheba and Carlsberg ridge system to the Makran subduction zone. We recently surveyed this fracture zone onboard the R/V Beautemps-Beaupré (Owen Cruise, March 2009) using a high-resolution deep-water multibeam echo-sounder. Bathymetric data reveal a spectacular submarine fault system running over a distance of 800 km between the Arabia-India-Somalia triple junction to the south and the Dalrymple Trough to the north. The morphology of the active faults is well preserved on the seafloor where fault scarps can be followed over hundreds of kilometres. The surficial trace of the faults is not obscured by the sediments of the aggrading deep-sea fan of the Indus River. The fault system is segmented in five main segments connected by pull apart basins. The length of the individual, apparently uninterrupted, segments is between 100 km and 220 km. The largest pull-apart basin at the latitude 20°N (20°N-Basin) corresponds to a right step-over of about 12 km between two fault segments. The 20°N-Basin is bounded by a normal fault scarp with a throw of 450-500 m. Numerous minor normal faults cutting the floor of the basin attest to recent activity. The 20°N-Basin is directly supplied in turbidity-current deposits by an active channel of the Indus fan. The preservation of tectonic features indicates that the dip-slip motion has exceeded the rate of burial by sediments. Some compressional structures are also deduced from

  9. Non-Dimensional Analysis of a Two-Dimensional Beam Using Linear Stiffness Matrix in Absolute Nodal Coordinate Formulation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kun Woo; Lee, Jae Wook; Jang, Jin Seok; Oh, Joo Young [Korea Institute of Industrial Technology, Cheonan (Korea, Republic of); Kim, Hyung Ryul [Agency for Defense Development, Daejeon (Korea, Republic of); Kang, Ji Heon; Yoo, Wan Suk [Pusan Nat’l Univ., Busan (Korea, Republic of)

    2017-01-15

    Absolute nodal coordinate formulation was developed in the mid-1990s, and is used in the flexible dynamic analysis. In the process of deriving the equation of motion, if the order of polynomial referring to the displacement field increases, then the degrees of freedom increase, as well as the analysis time increases. Therefore, in this study, the primary objective was to reduce the analysis time by transforming the dimensional equation of motion to a nondimensional equation of motion. After the shape function was rearranged to be non-dimensional and the nodal coordinate was rearranged to be in length dimension, the non-dimensional mass matrix, stiffness matrix, and conservative force was derived from the non-dimensional variables. The verification and efficiency of this nondimensional equation of motion was performed using two examples; cantilever beam which has the exact solution about static deflection and flexible pendulum.

  10. Mechanical evaluation of posterior wiring as a supplement to anterior cervical plate fixation.

    Science.gov (United States)

    Rao, Raj D; Wang, Mei; Singrakhia, Manoj D; McGrady, Linda M

    2004-10-15

    An in vitro experimental study was performed to examine 3-dimensional biomechanical stability of cervical fixations. To determine whether posterior interspinous wiring contributes to the rigidity of a single-level motion segment that has been plated anteriorly, and to determine the effects of this combined fixation on intradiscal pressure and spinal motion at the adjacent segments. Combined anterior and posterior column fixation is being increasingly used in a variety of clinical situations that do not involve complete disruption of the motion segment. The biomechanical validity of combined anterior posterior fixation in the absence of overt posterior ligamentous disruption has not been studied. Six human fresh-frozen cadaveric cervical spines (C3-T1) were used. Three-dimensional intersegmental motion and intradiscal pressure were measured while the spine was loaded in flexion, extension, lateral bending, and torsion (up to 2.5 Nm). Fixation stability at the operative level (C5-C6) and influence of the fixation on adjacent segments were evaluated after an anterior plating procedure and combined anterior plating and posterior wiring. Comparing the combined approach with anterior plating alone, significant reductions in C5-C6 motion was noted: 49% in flexion (P torsion (P bending was not significant (18% and 12%, respectively). The improved fixation had minimal influence on the adjacent segments. Combined anterior posterior fixation further reduces the segmental motion by almost 50% in flexion and extension, 33% and 39% in torsion, and does not significantly alter intradiscal pressure and spinal motion at adjacent segments.

  11. Effect of plate shapes in orifice plate type flowmeters

    International Nuclear Information System (INIS)

    Moeller, S.V.

    1984-01-01

    The study of unusual plate shapes in orifice plate type flowmeters is presented, with a view to providing data for the substitution of the plate with one centered circular orifice in those applications where its use is not possible. For this purpose, six pairs of plates with different forms, with and without chamfered edges, were made and tested in a closed water loop. Results show that, generally, the use of chamfers improves the results and, in the case of perforated and slotlike orificed plates, the narrow-ness of the fluid passage tends to make unnecessary its use. (Author) [pt

  12. Absolute measurement of the Hugoniot and sound velocity of liquid copper at multimegabar pressures

    Science.gov (United States)

    McCoy, Chad A.; Knudson, Marcus D.; Root, Seth

    2017-11-01

    Measurement of the Hugoniot and sound velocity provides information on the bulk modulus and Grüneisen parameter of a material at extreme conditions. The capability to launch multilayered (copper/aluminum) flyer plates at velocities in excess of 20 km/s with the Sandia Z accelerator has enabled high-precision sound-velocity measurements at previously inaccessible pressures. For these experiments, the sound velocity of the copper flyer must be accurately known in the multi-Mbar regime. Here we describe the development of copper as an absolutely calibrated sound-velocity standard for high-precision measurements at pressures in excess of 400 GPa. Using multilayered flyer plates, we performed absolute measurements of the Hugoniot and sound velocity of copper for pressures from 500 to 1200 GPa. These measurements enabled the determination of the Grüneisen parameter for dense liquid copper, clearly showing a density dependence above the melt transition. Combined with earlier data at lower pressures, these results constrain the sound velocity as a function of pressure, enabling the use of copper as a Hugoniot and sound-velocity standard for pressures up to 1200 GPa.

  13. Reconstruction of Northeast Asian Deformation Integrated with Western Pacific Plate Subduction since 200 Ma

    Science.gov (United States)

    Liu, S.; Gurnis, M.; Ma, P.; Zhang, B.

    2017-12-01

    The configuration and kinematics of continental deformation and its marginal plate tectonics on the Earth's surface are intrinsic manifestations of plate-mantle coupling. The complex interactions of plate boundary forces result in plate motions that are dominated by slab pull and ridge push forces and the effects of mantle drag; these interactions also result in continental deformation with a complex basin-mountain architecture and evolution. The kinematics and evolution of the western Pacific subduction and northeast Asian continental-margin deformation are a first-order tectonic process whose nature and chronology remains controversial. This paper implements a "deep-time" reconstruction of the western Pacific subduction, continental accretion or collision and basin-mountain deformation in northeast Asia since 200 Ma based on a newly revised global plate model. The results demonstrate a NW-SE-oriented shortening from 200-137 Ma, a NWW-SEE-oriented extension from 136-101 Ma, a nearly N-S-oriented extension and uplift with a short-term NWW-SEE-oriented compressional inversion in northeast China from 100-67 Ma, and a NW-SE- and nearly N-S-oriented extension from 66 Ma to the present day. The western Pacific oceanic plate subducted forward under East Asia along Mudanjiang-Honshu Island during the Jurassic, and the trenches retreated to the Sikhote-Alin, North Shimanto, and South Shimanto zones from ca. 137-128 Ma, ca. 130-90 Ma, and in ca. 60 Ma, respectively. Our time-dependent analysis of plate motion and continental deformation coupling suggests that the multi-plate convergent motion and ocean-continent convergent orogeny were induced by advance subduction during the Jurassic and earliest Cretaceous. Our analysis also indicates that the intra-continent rifting and back-arc extension were triggered by trench retreat during the Cretaceous and that the subduction of oceanic ridge and arc were triggered by trench retreat during the Cenozoic. Therefore, reconstructing

  14. Natural Frequency of F.G. Rectangular Plate by Shear Deformation Theory

    International Nuclear Information System (INIS)

    Shahrjerdi, Ali; Sapuan, S M; Shahzamanian, M M; Mustapha, F; Zahari, R; Bayat, M

    2011-01-01

    Natural frequency of functionally graded (F.G.) rectangular plate is carried out by using second-order shear deformation theory (SSDT). The material properties of functionally graded rectangular plates, except the Poisson's ratio, are assumed to vary continuously through the thickness of the plate in accordance with the exponential law distribution. The equations of motion are obtained by energy method. Numerical results for functionally graded plates are given in dimensionless graphical forms and the effects of material properties on natural frequency are determined.

  15. Modeling and management vibroacoustic emission homogeneous plate under the action of external forces concentrated

    Directory of Open Access Journals (Sweden)

    В.M. Макаренко

    2009-03-01

    Full Text Available  The model of rectangular plate acoustic radiation and transverse motion were presented, and its investigation was performed. The solution is received based on classisal plate theory. Vibration response and sound radiation of plates with simply-supported boundary conditions was discussed. Concentrated harmonic forces are used as an external excitation. The general confirmities to the law have been established for the changes of sound radiation, depending on the parameters of external excitations. An experiment was performed for justification of analytical approach, which is used for computations. Eigenfrequencies of free plate oscillations, which are received analytically, are in good agreement with experimental results.

  16. Outcome of distal end clavicle fractures treated with locking plates

    Directory of Open Access Journals (Sweden)

    Raju Vaishya

    2017-02-01

    Conclusion: The precontoured locking plates with lateral extension may be a good method to fix the fractures of the lateral end clavicle, which provide a stable fixation with good functional outcome with very few instances of stiffness and decreased range of motion of the shoulder with the hook plates and failure of fixation in screw and K-wire fixations. It may well be the answer to the fixation questions of the lateral clavicle fractures, although larger comparative studies between the surgical treatment methods are required to confirm the same.

  17. What is Needed for Absolute Paleointensity?

    Science.gov (United States)

    Valet, J. P.

    2015-12-01

    Many alternative approaches to the Thellier and Thellier technique for absolute paleointensity have been proposed during the past twenty years. One reason is the time consuming aspect of the experiments. Another reason is to avoid uncertainties in determinations of the paleofield which are mostly linked to the presence of multidomain grains. Despite great care taken by these new techniques, there is no indication that they always provide the right answer and in fact sometimes fail. We are convinced that the most valid approach remains the original double heating Thellier protocol provided that natural remanence is controlled by pure magnetite with a narrow distribution of small grain sizes, mostly single domains. The presence of titanium, even in small amount generates biases which yield incorrect field values. Single domain grains frequently dominate the magnetization of glass samples, which explains the success of this selective approach. They are also present in volcanic lava flows but much less frequently, and therefore contribute to the low success rate of most experiments. However the loss of at least 70% of the magnetization at very high temperatures prior to the Curie point appears to be an essential prerequisite that increases the success rate to almost 100% and has been validated from historical flows and from recent studies. This requirement can easily be tested by thermal demagnetization while low temperature experiments can document the detection of single domain magnetite using the δFC/δZFC parameter as suggested (Moskowitz et al, 1993) for biogenic magnetite.

  18. Bending, Vibration and Buckling of Laminated Composite Plates Using a Simple Four Variable Plate Theory

    Directory of Open Access Journals (Sweden)

    Atteshamuddin S. Sayyad

    Full Text Available Abstract In the present study, a simple trigonometric shear deformation theory is applied for the bending, buckling and free vibration of cross-ply laminated composite plates. The theory involves four unknown variables which are five in first order shear deformation theory or any other higher order theories. The in-plane displacement field uses sinusoidal function in terms of thickness co-ordinate to include the shear deformation effect. The transverse displacement includes bending and shear components. The present theory satisfies the zero shear stress conditions at top and bottom surfaces of plates without using shear correction factor. Equations of motion associated with the present theory are obtained using the dynamic version of virtual work principle. A closed form solution is obtained using double trigonometric series suggested by Navier. The displacements, stresses, critical buckling loads and natural frequencies obtained using present theory are compared with previously published results and found to agree well with those.

  19. Absolute polarization determinations of 33 pulsars using the Green Bank Telescope

    Science.gov (United States)

    Force, Megan M.; Demorest, Paul; Rankin, Joanna M.

    2015-11-01

    Absolute polarimetry observations of 33 pulsars were carried out with the Green Bank Telescope in the 1100-1900 MHz band using the Green Bank Ultimate Pulsar Processing Instrument. This group was selected to help complete a larger sample for which accurate proper-motion measurements were available. A combination of profile analysis using the core/double cone model and polarization-angle fitting methods were applied to estimate the `fiducial' longitude of the magnetic axis for each star and refer the linear polarization angle at that point to infinite frequency. As had been found previously, a number of the pulsars are found to have fiducial polarization directions that fall either along or at right angles to their proper-motion directions, whereas upwards of a third of the stars studied show alignments that are neither parallel nor orthogonal.

  20. Objects in Motion

    Science.gov (United States)

    Damonte, Kathleen

    2004-01-01

    One thing scientists study is how objects move. A famous scientist named Sir Isaac Newton (1642-1727) spent a lot of time observing objects in motion and came up with three laws that describe how things move. This explanation only deals with the first of his three laws of motion. Newton's First Law of Motion says that moving objects will continue…

  1. Rolling Shutter Motion Deblurring

    KAUST Repository

    Su, Shuochen

    2015-06-07

    Although motion blur and rolling shutter deformations are closely coupled artifacts in images taken with CMOS image sensors, the two phenomena have so far mostly been treated separately, with deblurring algorithms being unable to handle rolling shutter wobble, and rolling shutter algorithms being incapable of dealing with motion blur. We propose an approach that delivers sharp and undis torted output given a single rolling shutter motion blurred image. The key to achieving this is a global modeling of the camera motion trajectory, which enables each scanline of the image to be deblurred with the corresponding motion segment. We show the results of the proposed framework through experiments on synthetic and real data.

  2. Smoothing Motion Estimates for Radar Motion Compensation.

    Energy Technology Data Exchange (ETDEWEB)

    Doerry, Armin W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-07-01

    Simple motion models for complex motion environments are often not adequate for keeping radar data coherent. Eve n perfect motion samples appli ed to imperfect models may lead to interim calculations e xhibiting errors that lead to degraded processing results. Herein we discuss a specific i ssue involving calculating motion for groups of pulses, with measurements only available at pulse-group boundaries. - 4 - Acknowledgements This report was funded by General A tomics Aeronautical Systems, Inc. (GA-ASI) Mission Systems under Cooperative Re search and Development Agre ement (CRADA) SC08/01749 between Sandia National Laboratories and GA-ASI. General Atomics Aeronautical Systems, Inc. (GA-ASI), an affilia te of privately-held General Atomics, is a leading manufacturer of Remotely Piloted Aircraft (RPA) systems, radars, and electro-optic and rel ated mission systems, includin g the Predator(r)/Gray Eagle(r)-series and Lynx(r) Multi-mode Radar.

  3. Fuel cell end plate structure

    Science.gov (United States)

    Guthrie, Robin J.; Katz, Murray; Schroll, Craig R.

    1991-04-23

    The end plates (16) of a fuel cell stack (12) are formed of a thin membrane. Pressure plates (20) exert compressive load through insulation layers (22, 26) to the membrane. Electrical contact between the end plates (16) and electrodes (50, 58) is maintained without deleterious making and breaking of electrical contacts during thermal transients. The thin end plate (16) under compressive load will not distort with a temperature difference across its thickness. Pressure plate (20) experiences a low thermal transient because it is insulated from the cell. The impact on the end plate of any slight deflection created in the pressure plate by temperature difference is minimized by the resilient pressure pad, in the form of insulation, therebetween.

  4. Curves from Motion, Motion from Curves

    Science.gov (United States)

    2000-01-01

    tautochrone and brachistochrone properties. To Descartes, however, the rectification of curves such as the spiral (3) and the cycloid (4) was suspect - they...UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADP012017 TITLE: Curves from Motion, Motion from Curves DISTRIBUTION...Approved for public release, distribution unlimited This paper is part of the following report: TITLE: International Conference on Curves and Surfaces [4th

  5. Evaluation of the absolute regional temperature potential

    Directory of Open Access Journals (Sweden)

    D. T. Shindell

    2012-09-01

    Full Text Available The Absolute Regional Temperature Potential (ARTP is one of the few climate metrics that provides estimates of impacts at a sub-global scale. The ARTP presented here gives the time-dependent temperature response in four latitude bands (90–28° S, 28° S–28° N, 28–60° N and 60–90° N as a function of emissions based on the forcing in those bands caused by the emissions. It is based on a large set of simulations performed with a single atmosphere-ocean climate model to derive regional forcing/response relationships. Here I evaluate the robustness of those relationships using the forcing/response portion of the ARTP to estimate regional temperature responses to the historic aerosol forcing in three independent climate models. These ARTP results are in good accord with the actual responses in those models. Nearly all ARTP estimates fall within ±20% of the actual responses, though there are some exceptions for 90–28° S and the Arctic, and in the latter the ARTP may vary with forcing agent. However, for the tropics and the Northern Hemisphere mid-latitudes in particular, the ±20% range appears to be roughly consistent with the 95% confidence interval. Land areas within these two bands respond 39–45% and 9–39% more than the latitude band as a whole. The ARTP, presented here in a slightly revised form, thus appears to provide a relatively robust estimate for the responses of large-scale latitude bands and land areas within those bands to inhomogeneous radiative forcing and thus potentially to emissions as well. Hence this metric could allow rapid evaluation of the effects of emissions policies at a finer scale than global metrics without requiring use of a full climate model.

  6. Absolute Radiometric Calibration of KOMPSAT-3A

    Directory of Open Access Journals (Sweden)

    H. Y. Ahn

    2016-06-01

    Full Text Available This paper presents a vicarious radiometric calibration of the Korea Multi-Purpose Satellite-3A (KOMPSAT-3A performed by the Korea Aerospace Research Institute (KARI and the Pukyong National University Remote Sensing Group (PKNU RSG in 2015.The primary stages of this study are summarized as follows: (1 A field campaign to determine radiometric calibrated target fields was undertaken in Mongolia and South Korea. Surface reflectance data obtained in the campaign were input to a radiative transfer code that predicted at-sensor radiance. Through this process, equations and parameters were derived for the KOMPSAT-3A sensor to enable the conversion of calibrated DN to physical units, such as at-sensor radiance or TOA reflectance. (2 To validate the absolute calibration coefficients for the KOMPSAT-3A sensor, we performed a radiometric validation with a comparison of KOMPSAT-3A and Landsat-8 TOA reflectance using one of the six PICS (Libya 4. Correlations between top-of-atmosphere (TOA radiances and the spectral band responses of the KOMPSAT-3A sensors at the Zuunmod, Mongolia and Goheung, South Korea sites were significant for multispectral bands. The average difference in TOA reflectance between KOMPSAT-3A and Landsat-8 image over the Libya 4, Libya site in the red-green-blue (RGB region was under 3%, whereas in the NIR band, the TOA reflectance of KOMPSAT-3A was lower than the that of Landsat-8 due to the difference in the band passes of two sensors. The KOMPSAT-3Aensor includes a band pass near 940 nm that can be strongly absorbed by water vapor and therefore displayed low reflectance. Toovercome this, we need to undertake a detailed analysis using rescale methods, such as the spectral bandwidth adjustment factor.

  7. Absolute parameters of young stars: QZ Carinae

    Science.gov (United States)

    Walker, W. S. G.; Blackford, M.; Butland, R.; Budding, E.

    2017-09-01

    New high-resolution spectroscopy and BVR photometry together with literature data on the complex massive quaternary star QZ Car are collected and analysed. Absolute parameters are found as follows. System A: M1 = 43 (±3), M2 = 19 (+3 -7), R1 = 28 (±2), R2 = 6 (±2), (⊙); T1 ˜ 28 000, T2 ˜ 33 000 K; System B: M1 = 30 (±3), M2 = 20 (±3), R1 = 10 (±0.5), R2 = 20 (±1), (⊙); T1 ˜ 36 000, T2 ˜ 30 000 K (model dependent temperatures). The wide system AB: Period = 49.5 (±1) yr, Epochs, conjunction = 1984.8 (±1), periastron = 2005.3 (±3) yr, mean separation = 65 (±3), (au); orbital inclination = 85 (+5 -15) deg, photometric distance ˜2700 (±300) pc, age = 4 (±1) Myr. Other new contributions concern: (a) analysis of the timing of minima differences (O - C)s for the eclipsing binary (System B); (b) the width of the eclipses, pointing to relatively large effects of radiation pressure; (c) inferences from the rotational widths of lines for both Systems A and B; and (d) implications for theoretical models of early-type stars. While feeling greater confidence on the quaternary's general parametrization, observational complications arising from strong wind interactions or other, unclear, causes still inhibit precision and call for continued multiwavelength observations. Our high-inclination value for the AB system helps to explain failures to resolve the wide binary in the previous years. The derived young age independently confirms membership of QZ Car to the open cluster Collinder 228.

  8. Absolute nuclear material assay using count distribution (LAMBDA) space

    Science.gov (United States)

    Prasad, Manoj K [Pleasanton, CA; Snyderman, Neal J [Berkeley, CA; Rowland, Mark S [Alamo, CA

    2012-06-05

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  9. Planck absolute entropy of a rotating BTZ black hole

    Science.gov (United States)

    Riaz, S. M. Jawwad

    2018-04-01

    In this paper, the Planck absolute entropy and the Bekenstein-Smarr formula of the rotating Banados-Teitelboim-Zanelli (BTZ) black hole are presented via a complex thermodynamical system contributed by its inner and outer horizons. The redefined entropy approaches zero as the temperature of the rotating BTZ black hole tends to absolute zero, satisfying the Nernst formulation of a black hole. Hence, it can be regarded as the Planck absolute entropy of the rotating BTZ black hole.

  10. A form of MHD universal equations of unsteady incompressible fluid flow with variable elctroconductivity on heated moving plate

    Directory of Open Access Journals (Sweden)

    Boričić Zoran

    2005-01-01

    Full Text Available This paper deals with laminar, unsteady flow of viscous, incompressible and electro conductive fluid caused by variable motion of flat plate. Fluid electro conductivity is variable. Velocity of the plate is time function. Plate moves in its own plane and in "still" fluid. Present external magnetic filed is perpendicular to the plate. Plate temperature is a function of longitudinal coordinate and time. Viscous dissipation, Joule heat, Hole and polarization effects are neglected. For obtaining of universal equations system general similarity method is used as well as impulse and energy equation of described problem.

  11. Structural motion engineering

    CERN Document Server

    Connor, Jerome

    2014-01-01

    This innovative volume provides a systematic treatment of the basic concepts and computational procedures for structural motion design and engineering for civil installations. The authors illustrate the application of motion control to a wide spectrum of buildings through many examples. Topics covered include optimal stiffness distributions for building-type structures, the role of damping in controlling motion, tuned mass dampers, base isolation systems, linear control, and nonlinear control. The book's primary objective is the satisfaction of motion-related design requirements, such as restrictions on displacement and acceleration. The book is ideal for practicing engineers and graduate students. This book also: ·         Broadens practitioners' understanding of structural motion control, the enabling technology for motion-based design ·         Provides readers the tools to satisfy requirements of modern, ultra-high strength materials that lack corresponding stiffness, where the motion re...

  12. Experimental And Theoretical Stress Analysis For Composite Plate Under Combined Load

    Directory of Open Access Journals (Sweden)

    Emad Qasim Hussein

    2017-12-01

    Full Text Available The combined effects of thermal and mechanical loadings on the distribution of stress-strain for E-glass fiber /polyester composite plates are investigated experimentally and numerically. The experimental work has been carried out by applying to a uniform temperature and tensile load on the composite plate inside the furnace and the deformation of plate measured by a dial gauge. Two parameter studies, the fiber volume fraction and fiber orientation on the stress-strain for plates subjected to identical mechanical and temperature gradient. The results presented showed that, the maximum absolute of total strain in longitudinal direction occurred at 50 N tension load and fiber angle 60º, while the minimum absolute values of it occurred at 15 N tension loads and fiber angle 0º. However the maximum absolute of total strain in transverse direction occurred at 15N tension load and fiber angle 0º, while the minimum absolute values of it are obtained at 50 N tension loads and fiber angle 60º. Also, the total strain in longitudinal and transverse direction decrease with increasing the fiber volume fraction. Comparison of the results in the experimental test with the numerical analysis of the total strain and evaluated the agreement between the two methods used, the maximum discrepancywas 20%.

  13. Plate Full of Color

    Centers for Disease Control (CDC) Podcasts

    2008-08-04

    The Eagle Books are a series of four books that are brought to life by wise animal characters - Mr. Eagle, Miss Rabbit, and Coyote - who engage Rain That Dances and his young friends in the joy of physical activity, eating healthy foods, and learning from their elders about health and diabetes prevention. Plate Full of Color teaches the value of eating a variety of colorful and healthy foods.  Created: 8/4/2008 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 8/5/2008.

  14. design analysis of cam-follower system for beat up motion

    African Journals Online (AJOL)

    User

    A cam swing roller-follower mechanism is designed for the beat-up motion of a horizontal narrow loom. The system consists of a radial plate-cam driven by a camshaft keyed to the plate cam. A slay bar which act as the beater is attached to the radial swing roller-follower and assembled on the plate cam. A continuous ...

  15. Deformation of the Northwestern Okhotsk Plate: How is it happening?

    Science.gov (United States)

    Hindle, D.; Fujita, K.; Mackey, K.

    2009-09-01

    The Eurasia (EU) - North America (NA) plate boundary zone across Northeast Asia still presents many open questions within the plate tectonic paradigm. Constraining the geometry and number of plates or microplates present in the plate boundary zone is especially difficult because of the location of the EU-NA euler pole close to or even upon the EU-NA boundary. One of the major challenges remains the geometry of the Okhotsk plate (OK). whose northwestern portion terminates on the EU-OK-NA triple junction and is thus caught and compressed between converging EU and NA. We suggest that this leads to a coherent and understandable large scale deformation pattern of mostly northwest-southeast trending strike-slip faults which split Northwest OK into several extruding slivers. When the fault geometry is analysed together with space geodetic and focal mechanism data it suggests a central block which is extruding faster bordered east and west by progressively slower extruding blocks until the OK plate boundary faults are encountered. Taking into account elastic loading from both the intra-OK faults and the OK-Pacific (PA) boundary reconciles geodetic motions with geologic slip rates on at least the OK-NA boundary which corresponds to the Ulakhan fault.

  16. Optimization of Reaction Plates for Wave Energy Conversion

    Science.gov (United States)

    Brown, A. C.

    2014-12-01

    Reaction forces are generated as energy is extracted from the motion of ocean waves relative to a wave energy converter (WEC). The reaction forces effect the momentum of the WEC, and in most cases it is beneficial to transfer the loads to a relatively stationary external body. It has become common for WECs to include reaction plates that use hydrodynamic damping to transfer the loads developed during energy extraction to the relatively stationary water below the surface of the ocean. Reaction plates allow WECs to use compliant moorings, which reduce mooring loads and are more easily deployed than taut moorings. Heave plates are commonly used on offshore platforms, but the design of reaction plates for wave energy converters has received little attention. This work presents an initial optimization of reaction plate form to improve the heave and surge performance of the WEC reference models developed for the US Department of Energy. The benefits and drawbacks of various reaction plate geometries are compared, and the impacts on WEC stability, peak loading, and energy production are considered.

  17. Scattering and trapping of vortex pairs by a flat plate

    Science.gov (United States)

    Nitsche, Monika

    2017-11-01

    The interaction of a counter-rotating vortex pair with a flat plate in its path is studied numerically. The vortices are initially separated by a distance D and placed far upstream of a plate of length L. The plate is stationary, inclined relative to the incoming vortex trajectory, at an incident angle βi. Generally, the vortices surround the plate and then leave as a dipole with unchanged velocity, but with a large change in the transmitted travel direction. This transmitted angle depends sensitively on changes in the incident angle, with increasing sensitivity as D / L decreases. In fact, for sufficiently small D / L , the dependence on βi is highly singular. We show that there are intervals of incident angles in which the vortex trajectory undergoes repeated topological discontinuities, characterized by jumps in the vortex winding number and in the time they take to leave the plate. The discontinuities occur in a fractal self-similar fashion within the whole interval. These intervals furthermore contain incident angles that trap the vortices, which never leave the plate. The number of such trapping intervals increases as the parameter D / L decreases, and the dependence of the motion on βi becomes increasing complex.

  18. Mechanics and Partitioning of Deformation of the Northwestern Okhostk Plate, Northeast Russia

    Science.gov (United States)

    Hindle, D.; Mackey, K.; Fujita, K.

    2007-12-01

    The tectonic evolution and present day deformation of northeastern Russia remains one of the major challenges in plate tectonics. Arguments over the existence of at least a separate Okhotsk plate between North America and Eurasia appear to be resolved on the basis of the latest GPS studies combined with elastic modeling. The question of the mechanical behaviour of the Okhotsk plate, caught between the slowly, obliquely converging North American and Eurasian plates now becomes important. We present an analysis of geological lineaments, micro-seismicity, total seismic moment release and seismic deformation rate and GPS campaign data and global plate tectonic model data (REVEL) to estimate the likelihood of future seismicity and the relative amount of elastic and viscous deformation of the lithosphere of the northwestern Okhotsk plate. We find that it is likely that the Okhotsk plate is cracked into slivers, but that rates of relative motion of these slivers are close to indistinguishable from the behaviour of a single, rigid plate. The analysis also suggests the upper bound for large earthquakes in the region to be Mw 7-7.5 which we expect to occur only on the plate boundary fault itself. This fits geological evidence for a long term offset rate 5-10 times higher on the major plate boundary fault than other lineaments cutting the Okhotsk plate itself.

  19. Global Models of Ridge-Push Force, Geoid, and Lithospheric Strength of Oceanic plates

    Science.gov (United States)

    Mahatsente, Rezene

    2017-12-01

    An understanding of the transmission of ridge-push related stresses in the interior of oceanic plates is important because ridge-push force is one of the principal forces driving plate motion. Here, I assess the transmission of ridge-push related stresses in oceanic plates by comparing the magnitude of the ridge-push force to the integrated strength of oceanic plates. The strength is determined based on plate cooling and rheological models. The strength analysis includes low-temperature plasticity (LTP) in the upper mantle and assumes a range of possible tectonic conditions and rheology in the plates. The ridge-push force has been derived from the thermal state of oceanic lithosphere, seafloor depth and crustal age data. The results of modeling show that the transmission of ridge-push related stresses in oceanic plates mainly depends on rheology and predominant tectonic conditions. If a lithosphere has dry rheology, the estimated strength is higher than the ridge-push force at all ages for compressional tectonics and at old ages (>75 Ma) for extension. Therefore, under such conditions, oceanic plates may not respond to ridge-push force by intraplate deformation. Instead, the plates may transmit the ridge-push related stress in their interior. For a wet rheology, however, the strength of young lithosphere (stress may dissipate in the interior of oceanic plates and diffuses by intraplate deformation. The state of stress within a plate depends on the balance of far-field and intraplate forces.

  20. Sound transmission loss of double plates with an air cavity between them in a rigid duct.

    Science.gov (United States)

    Kim, Hyun-Sil; Kim, Sang-Ryul; Lee, Seong-Hyun; Seo, Yun-Ho; Ma, Pyung-Sik

    2016-05-01

    In this paper, the sound transmission loss (STL) of thin double plates with an air cavity between them in a rigid duct is considered using an analytical approach. The vibration motion of the plate and sound pressure field are expanded in terms of an infinite series of the modal functions. Under the plane wave condition, a low frequency solution is derived by including the first few symmetric modes. It is determined that the peak frequencies of the double plates coincide with those of each single plate. When the two plates are identical, the STL becomes zero at the natural frequencies of the single plate. However, when the two plates are not identical, the STL is always greater than zero. The location and amplitude of the dips are investigated using an approximate solution when the cavity depth is very small. It is observed that dividing the single plate into two plates with an air cavity in between degrades the STL in the low frequency range, while the equivalent surface mass density is preserved. However, when the cavity depth is not small, the STL of the single plate can be smaller than that of the double plates.

  1. Nonlinear dynamic response of a simply supported rectangular functionally graded material plate under the time-dependent thermal mechanical loads

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Y. X. [Beijing Information Science and Technology University, Beijing (China); Zhang, W. [Beijing University of Technology, Beijing (China); Yang, J. [RMIT University, Bundoora (Australia); Li, S. Y. [Ttianjin University of Technology and Education, Tianjin (China)

    2011-07-15

    An analysis on nonlinear dynamic characteristics of a simply supported functionally graded materials (FGMs) rectangular plate subjected to the transversal and in-plane excitations is presented in the time dependent thermal environment. Here we look the FGM Plates as isotropic materials which is assumed to be temperature dependent and graded in the thickness direction according to the power-law distribution in terms of volume fractions of the constituents. The geometrical nonlinearity using Von Karman's assumption is introduced. The formulation also includes in-plane and rotary inertia effects. In the framework of Reddy's third-order shear deformation plate theory, the governing equations of motion for the FGM plate are derived by the Hamilton's principle. Then the equations of motion with two degree- of-freedom under combined the time-dependent thermomechanical loads can be obtained by using Galerkin's method. Using numerical method, the control equations are analyzed to obtain the response curves. Under certain conditions the periodic and chaotic motions of the FGM plate are found. It is found that because of the existence of the temperature which relate to the time the motions of the FGM plate show the great difference. A period motion can be changed into the chaotic motions which are affected by the time dependent temperature.

  2. CMS Resistive plate Champers

    CERN Document Server

    Zainab, Karam

    2013-01-01

    There are many types of gas detectors which are used in CERN in LHC project, There is a main parts for the gas detectors which must be in all gas detectors types like Multiwire proportional chambers, such as the micromesh gaseous structure chamber (the MicroMegas), Gas-electron multiplier (GEM) detector, Resistive Plate Champers... Compact Muon Solenoid (CMS) experiment detecting muons which are powerful tool for recognizing signatures of interesting physics processes. The CMS detector uses: drift tube (DT), cathode strip chamber (CSC) and resistive plate chamber (RPC). Building RPC’s was my project in summer student program (hardware). RPC’s have advantages which are triggering detector and Excellent time resolution which reinforce the measurement of the correct beam crossing time. RPC’s Organized in stations :  RPC barrel (RB) there are 4 stations, namely RB1, RB2, RB3, and RB4  While in the RPC endcap (RE) the 3 stations are RE1, RE2, and RE3. In the endcaps a new starion will be added and this...

  3. Absolute testing of flats in sub-stitching interferometer by rotation-shift method

    Science.gov (United States)

    Jia, Xin; Xu, Fuchao; Xie, Weimin; Li, Yun; Xing, Tingwen

    2015-09-01

    Most of the commercial available sub-aperture stitching interferometers measure the surface with a standard lens that produces a reference wavefront, and the precision of the interferometer is generally limited by the standard lens. The test accuracy can be achieved by removing the error of reference surface by the absolute testing method. When the testing accuracy (repeatability and reproducibility) is close to 1nm, in addition to the reference surface, other factors will also affect the measuring accuracy such as environment, zoom magnification, stitching precision, tooling and fixture, the characteristics of optical materials and so on. We establish a stitching system in the thousand level cleanroom. The stitching system is including the Zygo interferometer, the motion system with Bilz active isolation system at level VC-F. We review the traditional absolute flat testing methods and emphasize the method of rotation-shift functions. According to the rotation-shift method we get the profile of the reference lens and the testing lens. The problem of the rotation-shift method is the tilt error. In the motion system, we control the tilt error no more than 4 second to reduce the error. In order to obtain higher testing accuracy, we analyze the influence surface shape measurement accuracy by recording the environment error with the fluke testing equipment.

  4. Bifurcation and chaos of thin circular functionally graded plate in thermal environment

    Energy Technology Data Exchange (ETDEWEB)

    Hu Yuda, E-mail: huyuda03@163.com [School of Civil Engineering and Mechanics, Yanshan University, Qinhuangdao 066004 (China); Zhang Zhiqiang, E-mail: zhangzqvib@126.com [School of Civil Engineering and Mechanics, Yanshan University, Qinhuangdao 066004 (China)

    2011-09-15

    Highlights: > We study bifurcations and chaotic dynamics of a FGM circular plate. > We consider the effect of temperature-dependent material properties. > Increasing volume fraction index will increase chaotic regions. > Increasing temperature will reduce chaotic regions. > The FGM plate exists chaotic motions, multiple periodic and periodic motions. - Abstract: A ceramic/metal functionally graded circular plate under one-term and two-term transversal excitations in the thermal environment is investigated, respectively. The effects of geometric nonlinearity and temperature-dependent material properties are both taken into account. The material properties of the functionally graded plate are assumed to vary continuously through the thickness, according to a power law distribution of the volume fraction of the constituents. Using the principle of virtual work, the nonlinear partial differential equations of FGM plate subjected to transverse harmonic forcing excitation and thermal load are derived. For the circular plate with clamped immovable edge, the Duffing nonlinear forced vibration equation is deduced using Galerkin method. The criteria for existence of chaos under one-term and two-term periodic perturbations are given with Melnikov method. Numerical simulations are carried out to plot the bifurcation curves for the homolinic orbits. Effects of the material volume fraction index and temperature on the criterions are discussed and the existences of chaos are validated by plotting phase portraits, Poincare maps. Also, the bifurcation diagrams and corresponding maximum Lyapunov exponents are plotted. It was found that periodic, multiple periodic solutions and chaotic motions exist for the FGM plate under certain conditions.

  5. Absolute chronology and stratigraphy of Lepenski Vir

    Directory of Open Access Journals (Sweden)

    Borić Dušan

    2007-01-01

    Full Text Available In the last decade, a number of specialist analyses were made on the material from old excavations of Mesolithic-Neolithic sites in the Danube Gorges. These new results altered significantly our understanding of the Lepenski Vir culture. The question of chronology of this regional phenomenon has been acute since the discovery of Lepenski Vir in the 1960s, and it remains of key importance for understanding the character of Mesolithic-Neolithic transformations in this and the neighbouring regions. The most heated debate was fuelled by the initial stratigraphic and chronological attribution of the type-site itself. There remained the question about the adequate dating of the most prominent phase at this site characterized by buildings with trapezoidal bases covered with limestone floors and with rectangular stone-lined hearths placed in the centre of these features. There have been suggestions that these features also contain Early Neolithic Starčevo type pottery and other similar items of material culture and should thus be dated to the Early Neolithic historical context. Moreover, the first series of conventional radiocarbon determinations (21 dates also suggested that the absolute chronology of these features should be confined to the period from around 6400-5500 cal BC (Fig. 1. Due to the importance of defining more precisely the chronology for the start of construction of these particular features at Lepenski Vir and for establishing the life-span of these buildings and their associated material culture, we have AMS (Accelerator Mass Spectrometry dated a number of contexts from this site. The results are presented in this paper. The project was made possible through the Oxford Radiocarbon Accelerate Dating Service (ORADS programme funded by the Arts and Humanities Research Council (AHRC and the Natural Environment Research Council (NERC of the Great Britain. Apart from those dates presented in this paper, there are 29 previously published

  6. Post-traumatic Raynaud's phenomenon following volar plate injury.

    Science.gov (United States)

    Chodakiewitz, Yosef G; Daniels, Alan H; Kamal, Robin N; Weiss, Arnold-Peter C

    2014-04-01

    Post-traumatic Raynaud's phenomenon following non-penetrating or non-repetitive injury is rare. We report a case of Raynaud's phenomenon occurring in a single digit 3 months following volar plate avulsion injury. Daily episodes of painless pallor of the digit occurred for 1 month upon any exposure to cold, resolving with warm water therapy. Symptoms resolved after the initiation of hand therapy, splinting, and range-of- motion exercises.

  7. Misconceptions and Conceptual Changes Concerning Continental Drift and Plate Tectonics among Portuguese Students Aged 16-17.

    Science.gov (United States)

    Marques, Luis; Thompson, David

    1997-01-01

    This study investigates student misconceptions in the areas of continent, ocean, permanence of ocean basins, continental drift, Earth's magnetic field, and plates and plate motions. A teaching-learning model was designed based on a constructivist approach. Results show that students held a substantial number of misconceptions. (Author/DKM)

  8. Differentiation of ankle sprain motion and common sporting motion by ankle inversion velocity.

    Science.gov (United States)

    Chu, Vikki Wing-Shan; Fong, Daniel Tik-Pui; Chan, Yue-Yan; Yung, Patrick Shu-Hang; Fung, Kwai-Yau; Chan, Kai-Ming

    2010-07-20

    This study investigated the ankle inversion and inversion velocity between various common motions in sports and simulated sprain motion, in order to provide a threshold for ankle sprain risk identification. The experiment was composed of two parts: firstly, ten male subjects wore a pair of sport shoes and performed ten trials of running, cutting, jump-landing and stepping-down motions. Secondly, five subjects performed five trials of simulated sprain motion by a supination sprain simulator. The motions were analyzed by an eight-camera motion capture system at 120 Hz. A force plate was employed to record the vertical ground reaction force and locate the foot strike time for common sporting motions. Ankle inversion and inversion velocity were calculated by a standard lower extremity biomechanics calculation procedure. Profiles of vertical ground reaction force, ankle inversion angle and ankle inversion velocity were obtained. Results suggested that the ankle was kept in an everted position during the stance. The maximum ankle inversion velocity ranged from 22.5 to 85.1 degrees/s and 114.0 to 202.5 degrees/s for the four tested motions and simulated sprain motion respectively. Together with the ankle inversion velocity reported in the injury case (623 degrees/s), a threshold of ankle inversion velocity of 300 degrees/s was suggested for the identification of ankle sprain. The information obtained in this study can serve as a basis for the development of an active protection apparatus for reducing ankle sprain injury. 2010 Elsevier Ltd. All rights reserved.

  9. Stability And Vibration Of Initially Stressed Thick Laminated Plates

    Science.gov (United States)

    Yang, I. H.; Kuo, W. S.

    1993-12-01

    Equations of motion for antisymmetric angle-ply plates in a general state of non-uniform initial stresses, where the effects of transverse shear and rotatory inertia are included, are derived by using Trefftz equations and the variational principle. These equations are then non-dimensionalized to a generic form by introducing global constants in orthotropic space and properly rearranging on-axis to off-axis stiffness relations for angle-ply laminates. Finally, the stability and vibration equations are solved for simply supported rectangular plates in a state of normal stress plus an edge twisting stress. The effects of twisting and the global material constants on the buckling and vibration of plates are studied.

  10. Does Absolute Synonymy exist in Owere-Igbo? | Omego | AFRREV ...

    African Journals Online (AJOL)

    Among Igbo linguistic researchers, determining whether absolute synonymy exists in Owere–Igbo, a dialect of the Igbo language predominantly spoken by the people of Owerri, Imo State, Nigeria, has become a thorny issue. While some linguistic scholars strive to establish that absolute synonymy exists in the lexical ...

  11. Determination of Absolute Zero Using a Computer-Based Laboratory

    Science.gov (United States)

    Amrani, D.

    2007-01-01

    We present a simple computer-based laboratory experiment for evaluating absolute zero in degrees Celsius, which can be performed in college and undergraduate physical sciences laboratory courses. With a computer, absolute zero apparatus can help demonstrators or students to observe the relationship between temperature and pressure and use…

  12. Stress-based elastodynamic discrete laminated plate theory

    Science.gov (United States)

    Schoeppner, G. A.; Wolfe, W. E.; Sandhu, R. S.

    1994-03-01

    A static laminated plate theory based on an assumed piecewise linear through-the-thickness in-plane stress distirbution has been extended to include inertia effects. Based on this in-plane stress distribution assumption, out-of-plane shear and normal stress component distributions were derived from the three-dimensional equations of motion, resulting in six nonzero stress components. Hamilton's variational principle was used to derive the plate equations of motion, the plate constitutive relationships, and the interface continuity equations. The governing equations were written in a form that is self-adjoint with respect to the convolution bilinear mapping. The resulting system of equations for a single lamina consists of 25 field equations in terms of 9 weighted displacement field variables, 10 stress and moment resultant field variables, and 6 out-of-plane shear and normal stress boundary field variables. For the laminated system, the mixed formulation enforces both traction and displacement continuity at lamina interfaces a it satisfies layer equilibrium. A finite element formulation based on a specialized form of the governing functional was developed. The method is illustrated with results of a free vibration analysis of sandwich and homogeneous plates for which exact solutions are available.

  13. Channel plate for DNA sequencing

    Science.gov (United States)

    Douthart, Richard J.; Crowell, Shannon L.

    1998-01-01

    This invention is a channel plate that facilitates data compaction in DNA sequencing. The channel plate has a length, a width and a thickness, and further has a plurality of channels that are parallel. Each channel has a depth partially through the thickness of the channel plate. Additionally an interface edge permits electrical communication across an interface through a buffer to a deposition membrane surface.

  14. A developmental study of latent absolute pitch memory.

    Science.gov (United States)

    Jakubowski, Kelly; Müllensiefen, Daniel; Stewart, Lauren

    2017-03-01

    The ability to recall the absolute pitch level of familiar music (latent absolute pitch memory) is widespread in adults, in contrast to the rare ability to label single pitches without a reference tone (overt absolute pitch memory). The present research investigated the developmental profile of latent absolute pitch (AP) memory and explored individual differences related to this ability. In two experiments, 288 children from 4 to12 years of age performed significantly above chance at recognizing the absolute pitch level of familiar melodies. No age-related improvement or decline, nor effects of musical training, gender, or familiarity with the stimuli were found in regard to latent AP task performance. These findings suggest that latent AP memory is a stable ability that is developed from as early as age 4 and persists into adulthood.

  15. Brain Image Motion Correction

    DEFF Research Database (Denmark)

    Jensen, Rasmus Ramsbøl; Benjaminsen, Claus; Larsen, Rasmus

    2015-01-01

    The application of motion tracking is wide, including: industrial production lines, motion interaction in gaming, computer-aided surgery and motion correction in medical brain imaging. Several devices for motion tracking exist using a variety of different methodologies. In order to use such devices...... offset and tracking noise in medical brain imaging. The data are generated from a phantom mounted on a rotary stage and have been collected using a Siemens High Resolution Research Tomograph for positron emission tomography. During acquisition the phantom was tracked with our latest tracking prototype...

  16. Motion and relativity

    CERN Document Server

    Infeld, Leopold

    1960-01-01

    Motion and Relativity focuses on the methodologies, solutions, and approaches involved in the study of motion and relativity, including the general relativity theory, gravitation, and approximation.The publication first offers information on notation and gravitational interaction and the general theory of motion. Discussions focus on the notation of the general relativity theory, field values on the world-lines, general statement of the physical problem, Newton's theory of gravitation, and forms for the equation of motion of the second kind. The text then takes a look at the approximation meth

  17. VISAS AND GREEN PLATES

    CERN Multimedia

    2000-01-01

    From 3 April 2000, all questions relating to visa requests for Switzerland, France, or Russia for a member of the personnel must be addressed to Ms. Agnita Querrou (telephone 72838, office 5-2-019, e-mail Agnita.Querrou@cern.ch).The Users' Office continues to deal with requests for letters of invitation and questions concerning visas for users in EP Division.Questions relating to removals, requests for green plates, to privileges of members of the personnel and to the importation of vehicles are still dealt with by Ms Zuzana Miller (telephone 79257, office 33-1-017, e-mail Zuzana.Muller@cern.ch) and Ms Joëlle Belleman (telephone 73962, office 33-1-019, e-mail Joelle.Belleman@cern.ch).

  18. Plate osteosynthesis of simple forearm fractures : LCP versus DC plates

    NARCIS (Netherlands)

    Stevens, Charles Tjerk; Ten Duis, Henk Jan

    The aim of this study was to compare the time to radiological bony union of simple A-type fractures of the forearm, treated with either a locking compression plate (LCP) or a dynamic compression plate (DCP). For each fracture, the relation between the use of compression and radiological healing time

  19. Nonlinear dynamics of a simply supported FGM rectangular plate under combined parametrical and external excitations

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Y; Lei, J [Beijing Institute of Machinery, Beijing 100085 (China); Zhang, W; Chen, L [College of Mechanical Engineering, Beijing University of Technology, Beijing 100022 (China)], E-mail: bimhao@sohu.com, E-mail: sandyzhang0@yahoo.com

    2008-02-15

    The present investigation deals with nonlinear oscillation behavior of a simply supported functionally graded rectangular plate in thermal environment with in-plane parametric and transverse external excitations. Material properties are assumed to be temperature-dependent. Based on the Reddy's third-order plate theory and the non-linear strain-displacement relations, the governing equations of motion for the FGM plate are derived by using the Hamilton's principle. The method of multiple scales is utilized to obtain four-dimensional nonlinear averaged equations. Using a numerical method, the averaged equations are analyzed. These results show that under certain conditions the periodic, multi-periodic solutions and chaotic motions of the FGM plates are found.

  20. Nonlinear dynamics of a simply supported FGM rectangular plate under combined parametrical and external excitations

    Science.gov (United States)

    Hao, Y.; Zhang, W.; Chen, L.; Lei, J.

    2008-02-01

    The present investigation deals with nonlinear oscillation behavior of a simply supported functionally graded rectangular plate in thermal environment with in-plane parametric and transverse external excitations. Material properties are assumed to be temperature-dependent. Based on the Reddy's third-order plate theory and the non-linear strain-displacement relations, the governing equations of motion for the FGM plate are derived by using the Hamilton's principle. The method of multiple scales is utilized to obtain four-dimensional nonlinear averaged equations. Using a numerical method, the averaged equations are analyzed. These results show that under certain conditions the periodic, multi-periodic solutions and chaotic motions of the FGM plates are found.

  1. Vibration Analysis of a Magnetoelectroelastic Rectangular Plate Based on a Higher-Order Shear Deformation Theory

    Directory of Open Access Journals (Sweden)

    Alireza Shooshtari

    Full Text Available Abstract Free vibration of a magnetoelectroelastic rectangular plate is investigated based on the Reddy's third-order shear deformation theory. The plate rests on an elastic foundation and it is considered to have different boundary conditions. Gauss's laws for electrostatics and magnetostatics are used to model the electric and magnetic behavior. The partial differential equations of motion are reduced to a single partial differential equation and then by using the Galerkin method, the ordinary differential equation of motion as well as an analytical relation for the natural frequency of the plate is obtained. Some numerical examples are presented to validate the proposed model and to investigate the effects of several parameters on the vibration frequency of the considered smart plate.

  2. Active buckling control of smart plate as diaphragm with PZT5 sensor/actuator patches

    Science.gov (United States)

    Viliani, N. S.; Pourrostami, H.; Mostafavi, S. M.; Hashemizadeh, F.; Safian, M. R.; Hashemi, M.

    2014-12-01

    In current study, buckling analyses of smart plate is presented. The various types of piezoelectric materials are under investigation for petrochemical industry and other applications. The PZT sensor output is used to determine the input to the PZT actuator using the feedback control algorithm for buckling control of FG plate. This study investigated the governing differential equations of motion of smart plate which includes FG plate as the membrane and PZT5 patches as actuator and sensor. The Fourier series method adopted to obtain the solution for the equation of motion. Also the effects of feedback gain and FGM volume fraction exponent on the critical buckling load for PZT-5A are studied. The potential application of current study can be found in optimal design of sensor's diaphragm. The variation of critical buckling load vs. feedback gain indicates that by increasing the feedback gain, the buckling load increases.

  3. Modeling particulate removal in plate-plate and wire-plate electrostatic precipitators

    Directory of Open Access Journals (Sweden)

    S Ramechecandane

    2016-09-01

    Full Text Available The present study is concerned with the modeling of electrically charged particles in a model plate-plate and a single wire-plate electrostatic precipitator (ESP. The particle concentration distributions for both a plate-plate and a wire-plate ESP are calculated using a modified drift flux model. Numerical investigations are performed using the modified drift flux model for particle number concentration, in addition to the RNG k - ε model for the mean turbulent flow field and the Poisson equation for the electric field. The proposed model and the outlined methodology for coupling the flow field, electric field, charging kinetics and particle concentration is applied to two model precipitators that are truly representative of a wide class of commercialized ESPs. The present investigation is quite different from the earlier studies as it does not make assumptions like a homogeneous electric field or an infinite turbulent diffusivity. The electric field calculated is a strong function of position and controls the migration velocity of particles. Hence, the proposed model can be implemented in a flow solver to obtain a full-fledged solution for any kind of ESP with no limitations on the particle number concentration, as encountered in a Lagrangian approach. The effect of turbulent diffusivity on particle number concentration in a plate-plate ESP is investigated in detail and the results obtained are compared with available experimental data. Similarly, the effect of particle size/diameter and applied electric potential on the accumulative collection performance in the case of a wire-plate ESP is studied and the results obtained are compared with available numerical data. The numerical results obtained using the modified drift flux model for both the plate-plate and wire-plate ESP are in close agreement with available experimental and numerical data.

  4. Regional neonatal brain absolute thermometry by 1H MRS.

    Science.gov (United States)

    Bainbridge, Alan; Kendall, Giles S; De Vita, Enrico; Hagmann, Cornelia; Kapetanakis, Andrew; Cady, Ernest B; Robertson, Nicola J

    2013-04-01

    Therapeutic hypothermia is standard care for infants with moderate to severe encephalopathy. (1) H MRS thermometry (MRSt) measures regional brain absolute temperature using the temperature-dependent water chemical shift. This study evaluates the clinical feasibility of MRSt in human neonates, and correlates white matter (WM) and thalamus (Thal) MRSt with conventional rectal temperature (Trectal ) measurement. Fifty-six infants born at term underwent perinatal MRSt for suspected hypoxic-ischaemic brain injury and 33 infants born preterm had MRSt at a term-equivalent age; 56 of the 89 had Trectal measured after MRSt of either a Thal or posterior WM voxel, or both. MRSt used point-resolved spectroscopy (no water suppression; TR = 1370 ms; TE = 288 ms; 1.5 × 1.5 × 1.5 cm(3) Thal and 1.1 × 1.3 × 1.4 cm(3) WM voxels). Time domain data were phase and frequency corrected before summation and motion-corrupted data were excluded from further analysis using simple criteria [preprocessing + quality assurance (QA)]. Two published water temperature-dependence calibrations [both using cerebral creatine (Cr), choline (Cho) and N-acetylaspartate (Naa) as independent reference peaks] were compared. The temperature measurements derived from Cr, Cho and Naa were combined to give a single amplitude-weighted combination temperature (TAWC ). WM and Thal TAWC correlated linearly with Trectal (Thal slope, 0.82 ± 0.04, R(2) = 0.85, p < 0.05; WM slope, 0.95 ± 0.04, R(2) = 0.78, p < 0.05). Preprocessing + QA improved the correlation between WM TAWC and Trectal (R(2) increased from 0.27 to 0.78, p < 0.001). Both calibration datasets showed specific inconsistencies between the temperatures calculated using Cr, Cho and Naa reference peaks when applied to this neonatal dataset. Neonatal MRSt is clinically feasible. Preprocessing + QA improved MRSt reliability in WM. The consideration of MRSt calibration internal biases is necessary before combining MRSt temperatures from multiple

  5. Using Google Earth to Explore Multiple Data Sets and Plate Tectonic Concepts

    Science.gov (United States)

    Goodell, L. P.

    2015-12-01

    Google Earth (GE) offers an engaging and dynamic environment for exploration of earth science data. While GIS software offers higher-level analytical capability, it comes with a steep learning curve and complex interface that is not easy for the novice, and in many cases the instructor, to negotiate. In contrast, the intuitive interface of GE makes it easy for students to quickly become proficient in manipulating the globe and independently exploring relationships between multiple data sets at a wide range of scales. Inquiry-based, data-rich exercises have been developed for both introductory and upper-level activities including: exploration of plate boundary characteristics and relative motion across plate boundaries; determination and comparison of short-term and long-term average plate velocities; crustal strain analysis (modeled after the UNAVCO activity); and determining earthquake epicenters, body-wave magnitudes, and focal plane solutions. Used successfully in undergraduate course settings, for TA training and for professional development programs for middle and high school teachers, the exercises use the following GE data sets (with sources) that have been collected/compiled by the author and are freely available for non-commercial use: 1) tectonic plate boundaries and plate names (Bird, 2003 model); 2) real-time earthquakes (USGS); 3) 30 years of M>=5.0 earthquakes, plotted by depth (USGS); 4) seafloor age (Mueller et al., 1997, 2008); 5) location and age data for hot spot tracks (published literature); 6) Holocene volcanoes (Smithsonian Global Volcanism Program); 7) GPS station locations with links to times series (JPL, NASA, UNAVCO); 8) short-term motion vectors derived from GPS times series; 9) long-term average motion vectors derived from plate motion models (UNAVCO plate motion calculator); 10) earthquake data sets consisting of seismic station locations and links to relevant seismograms (Rapid Earthquake Viewer, USC/IRIS/DELESE).

  6. Residual motions caused by micro-gravitational accelerations

    Science.gov (United States)

    Alexander, J. Iwan D.; Lundquist, Charles A.

    1987-01-01

    It is shown here that, under certain conditions, the low-frequency accelerations on experiments being performed aboard orbiting spacecraft due to gravity gradient, atmospheric drag, and spacecraft attitude or orientation can cause sustained fluid motions which require correction by advanced mass compensation techniques. The gravity gradient tensor is derived, and an expression for the difference between the absolute accelerations of a free particle and the mass center of the spacecraft is obtained. A model for the variation of atmospheric density with altitude is discussed, the equations governing the relative motion of a drag-free particle with respect to the mass center of the spacecraft are presented, and analytical and numerical solutions are obtained. Two possible spacecraft altitudes are considered. The problem of the Stokes motion of a sphere immersed in a viscous fluid is examined. Results are presented for the motion of a steel ball in water and for a triglycine sulfate crystal freely suspended in solution.

  7. The Terceira Rift as hyper-slow, hotspot-dominated oblique spreading axis: A comparison with other slow-spreading plate boundaries

    Science.gov (United States)

    Vogt, P. R.; Jung, W. Y.

    2004-01-01

    We suggest the 550 km long Terceira Rift (TR, Azores Plateau) is the world's slowest-spreading (hyper-slow, 4 mm/a plate separation; 2.3-3.8 mm/a perpendicular to oblique axial segments) organized accreting plate boundary. In its slightly sinuous (ca. 300 km radius of curvature) axial trace, its oblique spreading angles (ca. 40°-65°), and in frequency and first motions of earthquakes, the TR resembles better-known 'ultra-' or 'super-' slow spreading ridges (e.g. Gakkel and Southwest Indian ridges). Interpreted simply as volcanically 'unfilled' rift valley segments, the inter-island basins (e.g. the 3200 m deep Hirondelle Basin) are slightly wider (30-60 km), but not significantly deeper (1000-2200 m) than the Mid-Atlantic Ridge (MAR) median valley (20-28 mm/a; 10°N-53°N). However, along-axis segmentation wavelengths (ca. 100 km) are double those along the central MAR, but make TR comparable to the 'ultra-slow' (15-16 mm/a) Southwest Indian and Gakkel (7-13 mm/a) ridges. If this segmentation wavelength reflects Rayleigh-Taylor instabilities, the viscosity contrast between the overlying axial lithosphere and the partial melt zones is about an order of magnitude greater at ca. 4-16 mm/a than at 20-30 mm/a. The TR differs dramatically from ultra-slow ridges only in the large amplitude of along-strike topography (2000-4000 m; 4200 m total variation) owing perhaps to a copious melt flux from the Azores 'hotspot', combined with a spreading-rate-determined greater axial flexural strength and plate thickness, and slower export of volcanics from the rift axis. The probable TR youth (ca. 1 Ma?, requiring less than 4 km new oceanic crust) suggests lack of steady-state spreading conditions, which may explain the published gravity evidence against TR spreading. Absolute plate motions support the creation of the Azores Plateau by successive NE jumps of the rift axis to maintain its position over a fixed 'hotspot'.

  8. Mini-implants and miniplates generate sub-absolute and absolute anchorage.

    Science.gov (United States)

    Consolaro, Alberto

    2014-01-01

    The functional demand imposed on bone promotes changes in the spatial properties of osteocytes as well as in their extensions uniformly distributed throughout the mineralized surface. Once spatial deformation is established, osteocytes create the need for structural adaptations that result in bone formation and resorption that happen to meet the functional demands. The endosteum and the periosteum are the effectors responsible for stimulating adaptive osteocytes in the inner and outer surfaces. Changes in shape, volume and position of the jaws as a result of skeletal correction of the maxilla and mandible require anchorage to allow bone remodeling to redefine morphology, esthetics and function as a result of spatial deformation conducted by orthodontic appliances. Examining the degree of changes in shape, volume and structural relationship of areas where mini-implants and miniplates are placed allows us to classify mini-implants as devices of subabsolute anchorage and miniplates as devices of absolute anchorage.

  9. Mini-implants and miniplates generate sub-absolute and absolute anchorage

    Directory of Open Access Journals (Sweden)

    Alberto Consolaro

    2014-06-01

    Full Text Available The functional demand imposed on bone promotes changes in the spatial properties of osteocytes as well as in their extensions uniformly distributed throughout the mineralized surface. Once spatial deformation is established, osteocytes create the need for structural adaptations that result in bone formation and resorption that happen to meet the functional demands. The endosteum and the periosteum are the effectors responsible for stimulating adaptive osteocytes in the inner and outer surfaces.Changes in shape, volume and position of the jaws as a result of skeletal correction of the maxilla and mandible require anchorage to allow bone remodeling to redefine morphology, esthetics and function as a result of spatial deformation conducted by orthodontic appliances. Examining the degree of changes in shape, volume and structural relationship of areas where mini-implants and miniplates are placed allows us to classify mini-implants as devices of subabsolute anchorage and miniplates as devices of absolute anchorage.

  10. Dry Friction: Motions - Map and Characterization

    International Nuclear Information System (INIS)

    Motchongom-Tingue, M.; Kenfack-Jiotsa, A.; Tsobgni-Fozap, D.C.; Kofane, T.C.

    2009-12-01

    We consider a simple model of spring-mass block placed over a constant velocity v of a rolling plate. The map of the dynamic is presented in the (v,r) space where r accounts for the possible variation of the periodic shape profile of the rolling carpet. In order to characterize each type of motion, we found that evaluating the area of the phase space trajectories is more relevant than attempting on one hand, to solve analytically the asymptotic behavior or on the other hand, to obtain an equivalent of the entropy and the free energy. (author)

  11. Ground Motion Prediction for Great Interplate Earthquakes in Kanto Basin Considering Variation of Source Parameters

    Science.gov (United States)

    Sekiguchi, H.; Yoshimi, M.; Horikawa, H.

    2011-12-01

    Broadband ground motions are estimated in the Kanto sedimentary basin which holds Tokyo metropolitan area inside for anticipated great interplate earthquakes along surrounding plate boundaries. Possible scenarios of great earthquakes along Sagami trough are modeled combining characteristic properties of the source area and adequate variation in source parameters in order to evaluate possible ground motion variation due to next Kanto earthquake. South to the rupture area of the 2011 Tohoku earthquake along the Japan trench, we consider possible M8 earthquake. The ground motions are computed with a four-step hybrid technique. We first calculate low-frequency ground motions at the engineering basement. We then calculate higher-frequency ground motions at the same position, and combine the lower- and higher-frequency motions using a matched filter. We finally calculate ground motions at the surface by computing the response of the alluvium-diluvium layers to the combined motions at the engineering basement.

  12. Temporal logic motion planning

    CSIR Research Space (South Africa)

    Seotsanyana, M

    2010-01-01

    Full Text Available In this paper, a critical review on temporal logic motion planning is presented. The review paper aims to address the following problems: (a) In a realistic situation, the motion planning problem is carried out in real-time, in a dynamic, uncertain...

  13. Can molecular cell biology explain chromosome motions?

    Directory of Open Access Journals (Sweden)

    Gagliardi L

    2011-05-01

    Full Text Available Abstract Background Mitotic chromosome motions have recently been correlated with electrostatic forces, but a lingering "molecular cell biology" paradigm persists, proposing binding and release proteins or molecular geometries for force generation. Results Pole-facing kinetochore plates manifest positive charges and interact with negatively charged microtubule ends providing the motive force for poleward chromosome motions by classical electrostatics. This conceptual scheme explains dynamic tracking/coupling of kinetochores to microtubules and the simultaneous depolymerization of kinetochore microtubules as poleward force is generated. Conclusion We question here why cells would prefer complex molecular mechanisms to move chromosomes when direct electrostatic interactions between known bound charge distributions can accomplish the same task much more simply.

  14. Biomechanical comparison of the stable efficacy of two anterior plating systems.

    Science.gov (United States)

    Yang, Saiwei; Wang, Lee-Wei

    2003-07-01

    To compare the immediate stable efficacy and load sharing effect of two types of anterior cervical screw-plating instrumentations: the Morscher Synthes titanium locking screw-plate system and the Caspar trapezoidal screw-plate system. Fresh porcine cervical spines with intact, two surgery unstable models, and then reconstructed with or without screw-plating instruments were compared in three physiological loading conditions. Two markedly instrumentation systems--Morscher Synthes titanium cervical locking screw-plate and Caspar trapezoidal screw-plate systems are commonly used in management of complex cervical spine disorders. Although the biomechanical study showed that the lower cost Caspar system performed superior in extension before and after plate fatigue, the clinic evaluations of two systems were contradictory. So (1) does the titanium cervical locking plate system pay for its higher cost? and (2) what is the load sharing character of strut graft in one level corpectomy? Eight fresh ligamentous porcine cervical spines from C3 to C7 were undergone axial compression, rotation and sagittal flexion tests. The biomechanical experiment was sequentially repeated for the intact, C5-6 discectomy, C5 corpectomy, and then stabilized by either type of plate fixation devices with or without polymethylmethacrylate bone cement grafting. Strains measured by an extensometer across the operated motion segment were used as the index of stability. Analysis of the strain data showed both types of anterior fixation plate systems provided adequate-restored stability for the spinal column only aided with polymethylmethacrylate construction. Statistically, there was no significant difference in biomechanical evaluation for the stability effect between much cost Morscher Synthes plate and Caspar plate system (pfailure. Statistically both systems showed similar stable efficacy, however, the Morscher Synthes cervical locking plate system might provide better stable effect in higher

  15. Rapid change in drift of the Australian plate records collision with Ontong Java plateau.

    Science.gov (United States)

    Knesel, Kurt M; Cohen, Benjamin E; Vasconcelos, Paulo M; Thiede, David S

    2008-08-07

    The subduction of oceanic plateaux, which contain extraordinarily thick basaltic crust and are the marine counterparts of continental flood-basalt provinces, is an important factor in many current models of plate motion and provides a potential mechanism for triggering plate reorganization. To evaluate such models, it is essential to decipher the history of the collision between the largest and thickest of the world's oceanic plateaux, the Ontong Java plateau, and the Australian plate, but this has been hindered by poor constraints for the arrival of the plateau at the Melanesian trench. Here we present (40)Ar-(39)Ar geochronological data on hotspot volcanoes in eastern Australian that reveal a strong link between collision of the Greenland-sized Ontong Java plateau with the Melanesian arc and motion of the Australian plate. The new ages define a short-lived period of reduced northward plate motion between 26 and 23 Myr ago, coincident with an eastward offset in the contemporaneous tracks of seamount chains in the Tasman Sea east of Australia. These features record a brief westward deflection of the Australian plate as the plateau entered and choked the Melanesian trench 26 Myr ago. From 23 Myr ago, Australia returned to a rapid northerly trajectory at roughly the same time that southwest-directed subduction began along the Trobriand trough. The timing and brevity of this collisional event correlate well with offsets in hotspot seamount tracks on the Pacific plate, including the archetypal Hawaiian chain, and thus provide strong evidence that immense oceanic plateaux, like the Ontong Java, can contribute to initiating rapid change in plate boundaries and motions on a global scale.

  16. Laterally Loaded Nail-Plates

    DEFF Research Database (Denmark)

    Nielsen, Jacob; Rathkjen, Arne

    Load-displacement curves from about 200 short-term and laterally loaded nail-plate joints are analysed. The nail-plates are from Gang-Nail Systems, type GNA 20 S. The test specimens and the measuring systems are described. The tests are divided into 32 different series. The influence of the number...

  17. Seismic link at plate boundary

    Indian Academy of Sciences (India)

    time series to determine the causality and related orientation. The resulting link orientations at the plate boundary conditions indicate that causal triggering seems to be localized along a major fault, as a stress transfer between two major faults, and parallel to the geothermal area extension. 1. Introduction. Plate boundaries ...

  18. Scintillating plate calorimeter optical design

    International Nuclear Information System (INIS)

    McNeil, R.; Fazely, A.; Gunasingha, R.; Imlay, R.; Lim, J.

    1990-01-01

    A major technical challenge facing the builder of a general purpose detector for the SSC is to achieve an optimum design for the calorimeter. Because of its fast response and good energy resolution, scintillating plate sampling calorimeters should be considered as a possible technology option. The work of the Scintillating Plate Calorimeter Collaboration is focused on compensating plate calorimeters. Based on experimental and simulation studies, it is expected that a sampling calorimeter with alternating layers of high-Z absorber (Pb, W, DU, etc.) and plastic scintillator can be made compensating (e/h = 1.00) by suitable choice of the ratio of absorber/scintillator thickness. Two conceptual designs have been pursued by this subsystem collaboration. One is based on lead as the absorber, with read/out of the scintillator plates via wavelength shifter fibers. The other design is based on depleted uranium as the absorber with wavelength shifter (WLS) plate readout. Progress on designs for the optical readout of a compensating scintillator plate calorimeter are presented. These designs include readout of the scintillator plates via wavelength shifter plates or fiber readout. Results from radiation damage studies of the optical components are presented

  19. MyPlate Food Guide

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español MyPlate Food Guide KidsHealth / For Teens / MyPlate Food Guide What's ... and other sugary drinks. Avoid large portions . Five Food Groups Different food groups have different nutrients and ...

  20. Motion control systems

    CERN Document Server

    Sabanovic, Asif

    2011-01-01

    "Presents a unified approach to the fundamental issues in motion control, starting from the basics and moving through single degree of freedom and multi-degree of freedom systems In Motion Control Systems, Šabanovic and Ohnishi present a unified approach to very diverse issues covered in motion control systems, offering know-how accumulated through work on very diverse problems into a comprehensive, integrated approach suitable for application in high demanding high-tech products. It covers material from single degree of freedom systems to complex multi-body non-redundant and redundant systems. The discussion of the main subject is based on original research results and will give treatment of the issues in motion control in the framework of the acceleration control method with disturbance rejection technique. This allows consistent unification of different issues in motion control ranging from simple trajectory tracking to topics related to haptics and bilateral control without and with delay in the measure...

  1. Aseptic laboratory techniques: plating methods.

    Science.gov (United States)

    Sanders, Erin R

    2012-05-11

    Microorganisms are present on all inanimate surfaces creating ubiquitous sources of possible contamination in the laboratory. Experimental success relies on the ability of a scientist to sterilize work surfaces and equipment as well as prevent contact of sterile instruments and solutions with non-sterile surfaces. Here we present the steps for several plating methods routinely used in the laboratory to isolate, propagate, or enumerate microorganisms such as bacteria and phage. All five methods incorporate aseptic technique, or procedures that maintain the sterility of experimental materials. Procedures described include (1) streak-plating bacterial cultures to isolate single colonies, (2) pour-plating and (3) spread-plating to enumerate viable bacterial colonies, (4) soft agar overlays to isolate phage and enumerate plaques, and (5) replica-plating to transfer cells from one plate to another in an identical spatial pattern. These procedures can be performed at the laboratory bench, provided they involve non-pathogenic strains of microorganisms (Biosafety Level 1, BSL-1). If working with BSL-2 organisms, then these manipulations must take place in a biosafety cabinet. Consult the most current edition of the Biosafety in Microbiological and Biomedical Laboratories (BMBL) as well as Material Safety Data Sheets (MSDS) for Infectious Substances to determine the biohazard classification as well as the safety precautions and containment facilities required for the microorganism in question. Bacterial strains and phage stocks can be obtained from research investigators, companies, and collections maintained by particular organizations such as the American Type Culture Collection (ATCC). It is recommended that non-pathogenic strains be used when learning the various plating methods. By following the procedures described in this protocol, students should be able to: Perform plating procedures without contaminating media. Isolate single bacterial colonies by the streak-plating

  2. Strong Plate, Weak Slab Dichotomy

    Science.gov (United States)

    Petersen, R. I.; Stegman, D. R.; Tackley, P.

    2015-12-01

    Models of mantle convection on Earth produce styles of convection that are not observed on Earth.Moreover non-Earth-like modes, such as two-sided downwellings, are the de facto mode of convection in such models.To recreate Earth style subduction, i.e. one-sided asymmetric recycling of the lithosphere, proper treatment of the plates and plate interface are required. Previous work has identified several model features that promote subduction. A free surface or pseudo-free surface and a layer of material with a relatively low strength material (weak crust) allow downgoing plates to bend and slide past overriding without creating undue stress at the plate interface. (Crameri, et al. 2012, GRL)A low viscosity mantle wedge, possibly a result of slab dehydration, decouples the plates in the system. (Gerya et al. 2007, Geo)Plates must be composed of material which, in the case of the overriding plate, are is strong enough to resist bending stresses imposed by the subducting plate and yet, as in the case of the subducting plate, be weak enough to bend and subduct when pulled by the already subducted slab. (Petersen et al. 2015, PEPI) Though strong surface plates are required for subduction such plates may present a problem when they encounter the lower mantle.As the subducting slab approaches the higher viscosity, lower mantle stresses are imposed on the tip.Strong slabs transmit this stress to the surface.There the stress field at the plate interface is modified and potentially modifies the style of convection. In addition to modifying the stress at the plate interface, the strength of the slab affects the morphology of the slab at the base of the upper mantle. (Stegman, et al 2010, Tectonophysics)Slabs that maintain a sufficient portion of their strength after being bent require high stresses to unbend or otherwise change their shape.On the other hand slabs that are weakened though the bending process are more amenable to changes in morphology. We present the results of

  3. Incorrect Weighting of Absolute Performance in Self-Assessment

    Science.gov (United States)

    Jeffrey, Scott A.; Cozzarin, Brian

    Students spend much of their life in an attempt to assess their aptitude for numerous tasks. For example, they expend a great deal of effort to determine their academic standing given a distribution of grades. This research finds that students use their absolute performance, or percentage correct as a yardstick for their self-assessment, even when relative standing is much more informative. An experiment shows that this reliance on absolute performance for self-evaluation causes a misallocation of time and financial resources. Reasons for this inappropriate responsiveness to absolute performance are explored.

  4. Fundamental processes in ion plating

    International Nuclear Information System (INIS)

    Mattox, D.M.

    1980-01-01

    Ion plating is a generic term applied to film deposition processes in which the substrate surface and/or the depositing film is subjected to a flux of high energy particles sufficient to cause changes in the interfacial region of film properties compared to a nonbombarded deposition. Ion plating is being accepted as an alternative coating technique to sputter deposition, vacuum evaporation and electroplating. In order to intelligently choose between the various deposition techniques, the fundamental mechanisms, relating to ion plating, must be understood. This paper reviews the effects of low energy ion bombardment on surfaces, interface formation and film development as they apply to ion plating and the implementation and applications of the ion plating process

  5. Motion sickness in migraine sufferers.

    Science.gov (United States)

    Marcus, Dawn A; Furman, Joseph M; Balaban, Carey D

    2005-12-01

    Motion sickness commonly occurs after exposure to actual motion, such as car or amusement park rides, or virtual motion, such as panoramic movies. Motion sickness symptoms may be disabling, significantly limiting business, travel and leisure activities. Motion sickness occurs in approximately 50% of migraine sufferers. Understanding motion sickness in migraine patients may improve understanding of the physiology of both conditions. Recent literature suggests important relationships between the trigeminal system and vestibular nuclei that may have implications for both motion sickness and migraine. Studies demonstrating an important relationship between serotonin receptors and motion sickness susceptibility in both rodents and humans suggest possible new motion sickness prevention therapies.

  6. NATURAL TRANSVERSE VIBRATIONS OF A PRESTRESSED ORTHOTROPIC PLATE-STRIPE

    Directory of Open Access Journals (Sweden)

    Egorychev Oleg Aleksandrovich

    2012-10-01

    Full Text Available The article represents a new outlook at the boundary-value problem of natural vibrations of a homogeneous pre-stressed orthotropic plate-stripe. In the paper, the motion equation represents a new approximate hyperbolic equation (rather than a parabolic equation used in the majority of papers covering the same problem describing the vibration of a homogeneous orthotropic plate-stripe. The proposed research is based on newly derived boundary conditions describing the pin-edge, rigid, and elastic (vertical types of fixing, as well as the boundary conditions applicable to the unfixed edge of the plate. The paper contemplates the application of the Laplace transformation and a non-standard representation of a homogeneous differential equation with fixed factors. The article proposes a detailed representation of the problem of natural vibrations of a homogeneous orthotropic plate-stripe if rigidly fixed at opposite sides; besides, the article also provides frequency equations (no conclusions describing the plate characterized by the following boundary conditions: rigid fixing at one side and pin-edge fixing at the opposite side; pin-edge fixing at one side and free (unfixed other side; rigid fixing at one side and elastic fixing at the other side. The results described in the article may be helpful if applied in the construction sector whenever flat structural elements are considered. Moreover, specialists in solid mechanics and theory of elasticity may benefit from the ideas proposed in the article.

  7. The concurrent emergence and causes of double volcanic hotspot tracks on the Pacific plate.

    Science.gov (United States)

    Jones, T D; Davies, D R; Campbell, I H; Iaffaldano, G; Yaxley, G; Kramer, S C; Wilson, C R

    2017-05-25

    Mantle plumes are buoyant upwellings of hot rock that transport heat from Earth's core to its surface, generating anomalous regions of volcanism that are not directly associated with plate tectonic processes. The best-studied example is the Hawaiian-Emperor chain, but the emergence of two sub-parallel volcanic tracks along this chain, Loa and Kea, and the systematic geochemical differences between them have remained unexplained. Here we argue that the emergence of these tracks coincides with the appearance of other double volcanic tracks on the Pacific plate and a recent azimuthal change in the motion of the plate. We propose a three-part model that explains the evolution of Hawaiian double-track volcanism: first, mantle flow beneath the rapidly moving Pacific plate strongly tilts the Hawaiian plume and leads to lateral separation between high- and low-pressure melt source regions; second, the recent azimuthal change in Pacific plate motion exposes high- and low-pressure melt products as geographically distinct volcanoes, explaining the simultaneous emergence of double-track volcanism across the Pacific; and finally, secondary pyroxenite, which is formed as eclogite melt reacts with peridotite, dominates the low-pressure melt region beneath Loa-track volcanism, yielding the systematic geochemical differences observed between Loa- and Kea-type lavas. Our results imply that the formation of double-track volcanism is transitory and can be used to identify and place temporal bounds on plate-motion changes.

  8. The Golosyiv plate archive digitisation

    Science.gov (United States)

    Sergeeva, T. P.; Sergeev, A. V.; Pakuliak, L. K.; Yatsenko, A. I.

    2007-08-01

    The plate archive of the Main Astronomical Observatory of the National Academy of Sciences of Ukraine (Golosyiv, Kyiv) includes about 85 000 plates which have been taken in various observational projects during 1950-2005. Among them are about 25 000 of direct northern sky area plates and more than 600 000 plates containing stellar, planetary and active solar formations spectra. Direct plates have a limiting magnitude of 14.0-16.0 mag. Since 2002 we have been organising the storage, safeguarding, cataloguing and digitization of the plate archive. The very initial task was to create the automated system for detection of astronomical objects and phenomena, search of optical counterparts in the directions of gamma-ray bursts, research of long period, flare and other variable stars, search and rediscovery of asteroids, comets and other Solar System bodies to improve the elements of their orbits, informational support of CCD observations and space projects, etc. To provide higher efficiency of this work we have prepared computer readable catalogues and database for 250 000 direct wide field plates. Now the catalogues have been adapted to Wide Field Plate Database (WFPDB) format and integrated into this world database. The next step will be adaptation of our catalogues, database and images to standards of the IVOA. Some magnitude and positional accuracy estimations for Golosyiv archive plates have been done. The photometric characteristics of the images of NGC 6913 cluster stars on two plates of the Golosyiv's double wide angle astrograph have been determined. Very good conformity of the photometric characteristics obtained with external accuracies of 0.13 and 0.15 mag. has been found. The investigation of positional accuracy have been made with A3± format fixed bed scanner (Microtek ScanMaker 9800XL TMA). It shows that the scanner has non-detectable systematic errors on the X-axis, and errors of ± 15 μm on the Y-axis. The final positional errors are about ± 2 μm (

  9. Prognostic Value of Absolute versus Relative Rise of Blood ...

    African Journals Online (AJOL)

    maternal outcome than a relative rise in the systolic/diastolic blood pressure from mid pregnancy, which did not reach this absolute level. We conclude that in the Nigerian obstetric population, the practice of diagnosing pregnancy hypertension on ...

  10. Efficacy of intrahepatic absolute alcohol in unrespectable hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Farooqi, J.I.; Hameed, K.; Khan, I.U.; Shah, S.

    2001-01-01

    To determine efficacy of intrahepatic absolute alcohol injection in researchable hepatocellular carcinoma. A randomized, controlled, experimental and interventional clinical trial. Gastroenterology Department, PGMI, Hayatabad Medical Complex, Peshawar during the period from June, 1998 to June, 2000. Thirty patients were treated by percutaneous, intrahepatic absolute alcohol injection sin repeated sessions, 33 patients were not given or treated with alcohol to serve as control. Both the groups were comparable for age, sex and other baseline characteristics. Absolute alcohol therapy significantly improved quality of life of patients, reduced the tumor size and mortality as well as showed significantly better results regarding survival (P< 0.05) than the patients of control group. We conclude that absolute alcohol is a beneficial and safe palliative treatment measure in advanced hepatocellular carcinoma (HCC). (author)

  11. Changes in Absolute Sea Level Along U.S. Coasts

    Data.gov (United States)

    U.S. Environmental Protection Agency — This map shows changes in absolute sea level from 1960 to 2016 based on satellite measurements. Data were adjusted by applying an inverted barometer (air pressure)...

  12. Absolute Continuity of Stable Foliations for Mappings of Banach Spaces

    Science.gov (United States)

    Blumenthal, Alex; Young, Lai-Sang

    2017-09-01

    We prove the absolute continuity of stable foliations for mappings of Banach spaces satisfying conditions consistent with time- t maps of certain classes of dissipative PDEs. This property is crucial for passing information from submanifolds transversal to the stable foliation to the rest of the phase space; it is also used in proofs of ergodicity. Absolute continuity of stable foliations is well known in finite dimensional hyperbolic theory. On Banach spaces, the absence of nice geometric properties poses some additional difficulties.

  13. ON HAMILTONIAN FORMULATIONS AND CONSERVATION LAWS FOR PLATE THEORIES OF VEKUA-AMOSOV TYPE

    Directory of Open Access Journals (Sweden)

    Sergey I. Zhavoronok

    2017-12-01

    Full Text Available Some variants of the generalized Hamiltonian formulation of the plate theory of I. N. Vekua – A. A. Amosov type are presented. The infinite dimensional formulation with one evolution variable, or an “instantaneous” formalism, as well as the de Donder – Weyl one are considered, and their application to the numerical simulation of shell and plate dynamics is briefly discussed. The main conservation laws are formulated for the general plate theory of Nth order, and the possible motion integrals are introduced

  14. Vibration control of a functionally graded material plate patched with piezoelectric actuators and sensors under a constant electric charge

    Science.gov (United States)

    Kargarnovin, M. H.; Najafizadeh, M. M.; Viliani, N. S.

    2007-08-01

    In this paper active vibration control of functionally graded material (FGM) plates using piezoelectric sensor/actuator patches is studied. A simply supported FGM rectangular plate which is bonded with a piezoelectric rectangular patch (patches) on the top and/or bottom surface(s) as actuators/sensors is considered. When a constant electric charge is imposed, the governing differential equations of the motion are derived using classical laminated plate theory (CLPT). The solution for the motion equation is obtained using a Fourier series method and the effect of feedback gain and FGM volume fraction on the plate frequency and displacement (w) are studied. It is noticed that increasing the feedback gain leads to the reduction of frequency and displacement and therefore a better control of the plate's vibration. Moreover, by increasing the value of the FGM volume fraction the resonant frequency decreases.

  15. Repeated absolute gravity measurements for monitoring slow intraplate vertical deformation in Western Europe

    Science.gov (United States)

    Van Camp, M. J.; de Viron, O.; Scherneck, H.; Hinzen, K. G.; Williams, S. D.; Lecocq, T.; Quinif, Y.; Camelbeeck, T.

    2011-12-01

    In continental plate interiors, ground surface movements are at the limit of the noise level and close to or below the accuracy of current geodetic techniques. Absolute gravity measurements are valuable to quantify slow vertical movements, as this instrument is drift free and, unlike GPS, independent of the terrestrial reference frame. Repeated absolute gravity (AG) measurements have been performed in Oostende (Belgian coastline) and at 8 stations along a southwest-northeast profile across the Belgian Ardennes and the Roer Valley Graben (Germany), in order to estimate the tectonic deformation in the area. The AG measurements, repeated once or twice a year, can resolve elusive gravity changes with a precision better than 3.7 nm/s2/yr (95% confidence interval) after 11 years, even in difficult conditions. After 8-15 years (depending on the station), we find that the gravity rates of change lie in the [-3.1, 8.1] nm/s2/yr interval and result from a combination of anthropogenic, climatic, tectonic, and Glacial Isostatic Adjustment (GIA) effects. After correcting for the GIA, the inferred gravity rates and consequently, the vertical land movements, reduce to zero within the uncertainty level at all stations except Jülich (due to man-induced subsidence) and Sohier (possibly, an artefact due to the shortness of the time series at that station).

  16. Tectonic, Climatic and Anthropogenic Vertical Land Movements in Western Europe by Repeated Absolute Gravity Measurements

    Science.gov (United States)

    van Camp, M. J.; de Viron, O.; Lecocq, T.; Hinzen, K. G.; Quinif, Y.; Williams, S. D.; Camelbeeck, T.

    2010-12-01

    In continental plate interiors, tectonic deformations are small and the associated ground surface movements remain close to or below the accuracy of current geodetic techniques, and at the limit of the noise level. An absolute gravimeter is an appropriate tool to quantify slow vertical movements, as this instrument, based on length and time standards, is drift free and does not depend on any terrestrial reference frame. Repeated absolute gravity (AG) measurements have been performed in Oostende (Belgian coastline) and at 8 stations along a southwest-northeast profile across the Belgian Ardennes and the Roer Valley Graben (Germany), in order to estimate the tectonic deformations in the area. After 7-13 years (depending on the station), we find evidence that the movements are no larger than a few millimeter per year and result from a combination of anthropogenic, climatic, tectonic, and Glacial Isostatic Adjustment (GIA) effects. This demonstrates the importance of precisely modeling the GIA effects in order to investigate intraplate tectonic deformations at the sub-millimeter level. This study also shows that AG measurements, repeated once or twice a year, can resolve vertical velocities at the 1.0 mm/yr level after 10 years, even in difficult conditions, provided that the gravimeter is carefully maintained.

  17. Absolute measurement of the 242Pu neutron-capture cross section

    Science.gov (United States)

    Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; Bucher, B.; Chyzh, A.; Bredeweg, T. A.; Baramsai, B.; Couture, A.; Jandel, M.; Mosby, S.; O'Donnell, J. M.; Ullmann, J. L.; Dance Collaboration

    2016-04-01

    The absolute neutron-capture cross section of 242Pu was measured at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array along with a compact parallel-plate avalanche counter for fission-fragment detection. The first direct measurement of the 242Pu(n ,γ ) cross section was made over the incident neutron energy range from thermal to ≈6 keV, and the absolute scale of the (n ,γ ) cross section was set according to the known 239Pu(n ,f ) resonance at En ,R=7.83 eV. This was accomplished by adding a small quantity of 239Pu to the 242Pu sample. The relative scale of the cross section, with a range of four orders of magnitude, was determined for incident neutron energies from thermal to ≈40 keV. Our data, in general, are in agreement with previous measurements and those reported in ENDF/B-VII.1; the 242Pu(n ,γ ) cross section at the En ,R=2.68 eV resonance is within 2.4 % of the evaluated value. However, discrepancies exist at higher energies; our data are ≈30 % lower than the evaluated data at En≈1 keV and are approximately 2 σ away from the previous measurement at En≈20 keV.

  18. Management of Intra-Articular Distal Radius Fractures: Volar or Dorsal Locking Plate-Which Has Fewer Complications?

    Science.gov (United States)

    Abe, Yoshihiro; Tokunaga, Susumu; Moriya, Takuro

    2017-11-01

    The aim of this study was to compare the functional outcomes and complications of volar and dorsal plating for the management of intra-articular distal radius fractures, with special regard to indications for dorsal plating. Furthermore, we examine the rationale for choosing dorsal plating and its frequency of use. Clinical assessments included range of motion measurements at the wrist; grip strength; the Quick Disabilities of the Arm, Shoulder, and Hand score; and the Gartland and Werley score. Clinical results were compared with those achieved using a volarly placed locking plate system. According to Lutsky's plate theory, the rationale for choosing dorsal plating was based on 4 types of pathologic fractures. Of 112 patients, 38 patients were treated with open reduction internal fixation via a dorsal approach and 68 patients were treated using a volar approach. Except for wrist flexion, there were no other statistical differences in the clinical results between groups for both subjective and objective parameters. There were no statistically significant differences in the complication rates between the volar and dorsal plated groups. One serious complication occurred after volar plating. The most common reason for choosing dorsal plating was irreducible dorsal die-punch fractures. The treatment of displaced intra-articular distal radius fractures with a dorsally versus a volarly placed interlocking plate system demonstrated similar clinical results. Postoperative complications were not readily observed in the patients treated with a dorsal locking plate. Certain fracture patterns are more appropriately stabilized using a dorsal plate fixation.

  19. Stability of Plates and Plated Structures - General Report

    Czech Academy of Sciences Publication Activity Database

    Maquoi, R.; Škaloud, Miroslav

    2000-01-01

    Roč. 55, 1-3 (2000), s. 45-68 ISSN 0143-974X. [Stability and Ductility of Steel Structures . Timisoara, 09.09.1999-11.09.1999] R&D Projects: GA ČR GA103/97/0002; GA AV ČR IAA2071701 Keywords : stability * plates * plated structures * web breathing * design Subject RIV: JM - Building Engineering Impact factor: 0.418, year: 2000

  20. Plating on stainless steel alloys

    International Nuclear Information System (INIS)

    Dini, J.W.; Johnson, H.R.

    1981-01-01

    Quantitative adhesion data are presented for a variety of electroplated stainless steel type alloys. Results show that excellent adhesion can be obtained by using a Wood's nickel strike or a sulfamate nickel strike prior to final plating. Specimens plated after Wood's nickel striking failed in the deposit rather than at the interface between the substrate and the coating. Flyer plate quantitative tests showed that use of anodic treatment in sulfuric acid prior to Wood's nickel striking even further improved adhesion. In contrast activation of stainless steels by immersion or cathodic treatment in hydrochloric acid resulted in very reduced bond strengths with failure always occurring at the interface between the coating and substrate

  1. Oblique Wave-Induced Responses of A VLFS Edged with A Pair of Inclined Perforated Plates

    Science.gov (United States)

    Cheng, Yong; Ji, Chun-yan; Zhai, Gang-jun; Oleg, Gaidai

    2018-03-01

    This paper is concerned with the hydroelastic responses of a mat-like, rectangular very large floating structure (VLFS) edged with a pair of horizontal/inclined perforated anti-motion plates in the context of the direct coupling method. The updated Lagrangian formulae are applied to establish the equilibrium equations of the VLFS and the total potential formula is employed for fluids in the numerical model including the viscous effect of the perforated plates through the Darcy's law. The hybrid finite element-boundary element (FE-BE) method is implemented to determine the response reduction of VLFS with attached perforated plates under various oblique incident waves. Also, the numerical solutions are validated against a series of experimental tests. The effectiveness of the attached perforated plates in reducing the deflections of the VLFS can be significantly improved by selecting the proper design parameters such as the porous parameter, submergence depth, plate width and inclination angle for the given sea conditions.

  2. Preliminary experiments using light-initiated high explosive for driving thin flyer plates

    International Nuclear Information System (INIS)

    Benham, R.A.

    1980-02-01

    Light-initiated high explosive, silver acelytide - silver-nitrate (SASN), has been used to produce simulated x ray blow-off impulse loading on reentry vehicles to study the system structural response. SASN can be used to accelerate thin flyer plates to high terminal velocities which, in turn, can deliver a pressure pulse that can be tailored to the target material. This process is important for impulse tests where both structural and material response is desired. The theories used to calculate the dynamic state of the flyer plate prior to impact are summarized. Data from several experiments are presented which indicate that thin flyer plates can be properly accelerated and that there are predictive techniques available which are adequate to calculate the motion of the flyer plate. Recommendations are made for future study that must be undertaken to make the SASN flyer plate technique usable

  3. Nonlinear dynamic response and active vibration control for piezoelectric functionally graded plate

    Science.gov (United States)

    Yiqi, Mao; Yiming, Fu

    2010-05-01

    The nonlinear dynamic response and active vibration control of the piezoelectric functionally graded plate are analyzed in this paper. Based on higher-order shear plate theory and elastic piezoelectric theory, the nonlinear geometric and constitutive relations of the piezoelectric functionally graded plate are established, and then the nonlinear motion equations of the piezoelectric functionally graded plate are obtained through Hamilton's variational principle. The nonlinear active vibration control of the structure is carried out with adoption of the negative velocity feedback control algorithm. By applying finite difference method, the whole problem is solved by using iterative method synthetically. In numerical examples, the effects of mechanical load, electric load, the volume fraction and the geometric parameters on the dynamic response and vibration control of the piezoelectric FGM plate are investigated.

  4. Modern geodynamical motion of the Northern Caucasus from data of GPS/GLONASS observations

    Science.gov (United States)

    Milyukov, Vadim; Zharov, Vladimir; Mironov, Alexey; Myasnikov, Andrey; Kaufman, Mark

    2010-05-01

    The northern part of the Greater Caucasus is one of the most geodynamically active regions of Russia. This is a zone of complex tectonics resulting from interaction between two of the Earth's major lithospheric plates, Arabia and Eurasia. Therefore, the region as a whole is characterized by a complex system of faults, with meridional and diagonal structures. The first GPS and absolute gravity campaign in the Black Sea and Northern Caucasus regions was carried out between 1993 and 1994 as part of the SELF project. One of the points of the GPS measurements was transformed in the stationary station. This station is located in Karatchay-Cherkessia Republic of the Russian Federation. Since 1997 the Zelenchukskaya station has been part of the European Reference Frame (EUREF) GPS network with a code ZECK. Within the last few years we have established three new stationary GPS/GLONASS stations in the Northern Caucasus. The first (site code TRSK) is located in the Kabardino-Balkaria Republic, near the Elbrus volcano. It began to operate in 2005. The second one is located in Karatchay-Cherkessia Republic (site code KISL). This station has been in operation since 2006. The third is located in Vladikavkaz, the capital of North Ossetia Republic (site code VLAD). The continuous GPS measurements began in 2008. These four stationary stations form the base for the regional Northern Caucasus GPS network, which can be called the Northern Caucasus Deformation Array (NCDA). We analyse the GPS data using BERNESE 5.0 GPS software. As a reference site we use the Mendeleevo station, located in the Moscow region (IGS site code MDVJ). The striking aspect of the velocity field of the Northern Caucasus derived from the NDCA stations is the rapid motion in the north-east direction with almost equal velocities of about 28 mm/yr. The motion of the feducial site MDVJ (Moscow region) is characterised by a similar velocity value (25 mm/yr) in the same direction. Therefore the motion of the Northern

  5. Updated velocity field for the Caribbean plate from COCONet GPS observations

    Science.gov (United States)

    Miller, J. A.; Mattioli, G. S.; Jansma, P. E.

    2013-05-01

    The currently accepted kinematic model of the Caribbean plate presented by DeMets et al., 2007, is based on velocities from 6 continuous and 14 campaign GPS sites. Our work attempts to refine the current plate model by evaluating data from the 60+ continuous GPS stations that comprise COCONet. COCONet (Continuously Operating Caribbean Observation Network) is an NSF-funded collaborative natural hazards research effort that has enhanced the geodetic infrastructure in the region surrounding the Caribbean plate. Data for this study was obtained from the open data archive at UNAVCO. GPS data have been processed with an absolute point positioning strategy using GIPSY-OASIS II, using the non-fiducial, final precise clock and orbit parameters provided by JPL. An updated velocity field for the Caribbean plate will be presented and co-seismic and post-seismic slip, recorded by network stations will be examined for earthquakes that have occurred within the COCONet footprint.

  6. Non-newtonian flow and pressure drop of pineapple juice in a plate heat exchanger

    Directory of Open Access Journals (Sweden)

    R. A. F. Cabral

    2010-12-01

    Full Text Available The study of non-Newtonian flow in plate heat exchangers (PHEs is of great importance for the food industry. The objective of this work was to study the pressure drop of pineapple juice in a PHE with 50º chevron plates. Density and flow properties of pineapple juice were determined and correlated with temperature (17.4 < T < 85.8ºC and soluble solids content (11.0 < Xs < 52.4 ºBrix. The Ostwald-de Waele (power law model described well the rheological behavior. The friction factor for non-isothermal flow of pineapple juice in the PHE was obtained for diagonal and parallel/side flow. Experimental results were well correlated with the generalized Reynolds number (20 < Re g < 1230 and were compared with predictions from equations from the literature. The mean absolute error for pressure drop prediction was 4% for the diagonal plate and 10% for the parallel plate.

  7. Fast Optimal Motion Planning

    Data.gov (United States)

    National Aeronautics and Space Administration — Computationally-efficient, fast and real-time, and provably-optimal motion planner for systems with highly nonlinear dynamics that can be extended for cooperative...

  8. Motion Sickness: First Aid

    Science.gov (United States)

    ... com. Accessed July 29, 2017. Priesol AJ. Motion sickness. https://www.uptodate.com/content/search. Accessed July 29, 2017. Brunette GW, et al. CDC Health Information for International Travel 2018. New York, N. ...

  9. Toying with Motion.

    Science.gov (United States)

    Galus, Pamela J.

    2002-01-01

    Presents a variety of activities that support the development of an understanding of Newton's laws of motion. Activities use toy cars, mobile roads, and a seat-of-nails. Includes a scoring rubric. (DDR)

  10. Lithospheric deformation in the Africa-Iberia plate boundary: Improved neotectonic modeling testing a basal-driven Alboran plate

    Science.gov (United States)

    Neres, M.; Carafa, M. M. C.; Fernandes, R. M. S.; Matias, L.; Duarte, J. C.; Barba, S.; Terrinha, P.

    2016-09-01

    We present an improved neotectonic numerical model of the complex NW Africa-SW Eurasia plate boundary segment that runs from west to east along the Gloria Fault up to the northern Algerian margin. We model the surface velocity field and the ongoing lithospheric deformation using the most recent version of the thin-shell code SHELLS and updated lithospheric model and fault map of the region. To check the presence versus the absence of an independently driven Alboran domain, we develop two alternative plate models: one does not include an Alboran plate; another includes it and determines the basal shear tractions necessary to drive it with known velocities. We also compare two alternative sets of Africa-Eurasia velocity boundary conditions, corresponding to geodetic and geological-scale averages of plate motion. Finally, we perform an extensive parametric study of fault friction coefficient, trench resistance, and velocities imposed in Alboran nodes. The final run comprises 5240 experiments, each scored to geodetic velocities (estimated for 250 stations and here provided), stress direction data, and seismic strain rates. The model with the least discrepancy to the data includes the Alboran plate driven by a basal WSW directed shear traction, slightly oblique to the westward direction of Alboran motion. We provide estimates of long-term strain rates and slip rates for the modeled faults, which can be useful for further hazard studies. Our results support that a mechanism additional to the Africa-Eurasia convergence is required to drive the Alboran domain, which can be related to subduction processes occurring within the mantle.

  11. Motion of a Pendulum

    Directory of Open Access Journals (Sweden)

    Jared Wynn

    2010-01-01

    Full Text Available The objective of this project is to derive and solve the equation of motion for a pendulum swinging at small angles in one dimension. The pendulum may be either a simple pendulum like a ball hanging from a string or a physical pendulum like a pendulum on a clock. For simplicity, we only considered small rotational angles so that the equation of motion becomes a harmonic oscillator.

  12. Encoding of yaw in the presence of distractor motion: studies in a fly motion sensitive neuron.

    Science.gov (United States)

    Roy, Suva; Sinha, Shiva R; de Ruyter van Steveninck, Rob

    2015-04-22

    Motion estimation is crucial for aerial animals such as the fly, which perform fast and complex maneuvers while flying through a 3-D environment. Motion-sensitive neurons in the lobula plate, a part of the visual brain, of the fly have been studied extensively for their specialized role in motion encoding. However, the visual stimuli used in such studies are typically highly simplified, often move in restricted ways, and do not represent the complexities of optic flow generated during actual flight. Here, we use combined rotations about different axes to study how H1, a wide-field motion-sensitive neuron, encodes preferred yaw motion in the presence of stimuli not aligned with its preferred direction. Our approach is an extension of "white noise" methods, providing a framework that is readily adaptable to quantitative studies into the coding of mixed dynamic stimuli in other systems. We find that the presence of a roll or pitch ("distractor") stimulus reduces information transmitted by H1 about yaw, with the amount of this reduction depending on the variance of the distractor. Spike generation is influenced by features of both yaw and the distractor, where the degree of influence is determined by their relative strengths. Certain distractor features may induce bidirectional responses, which are indicative of an imbalance between global excitation and inhibition resulting from complex optic flow. Further, the response is shaped by the dynamics of the combined stimulus. Our results provide intuition for plausible strategies involved in efficient coding of preferred motion from complex stimuli having multiple motion components. Copyright © 2015 the authors 0270-6474/15/356481-14$15.00/0.

  13. 2-tier in-plane motion correction and out-of-plane motion filtering for contrast-enhanced ultrasound.

    Science.gov (United States)

    Ta, Casey N; Eghtedari, Mohammad; Mattrey, Robert F; Kono, Yuko; Kummel, Andrew C

    2014-11-01

    Contrast-enhanced ultrasound (CEUS) cines of focal liver lesions (FLLs) can be quantitatively analyzed to measure tumor perfusion on a pixel-by-pixel basis for diagnostic indication. However, CEUS cines acquired freehand and during free breathing cause nonuniform in-plane and out-of-plane motion from frame to frame. These motions create fluctuations in the time-intensity curves (TICs), reducing the accuracy of quantitative measurements. Out-of-plane motion cannot be corrected by image registration in 2-dimensional CEUS and degrades the quality of in-plane motion correction (IPMC). A 2-tier IPMC strategy and adaptive out-of-plane motion filter (OPMF) are proposed to provide a stable correction of nonuniform motion to reduce the impact of motion on quantitative analyses. A total of 22 cines of FLLs were imaged with dual B-mode and contrast specific imaging to acquire a 3-minute TIC. B-mode images were analyzed for motion, and the motion correction was applied to both B-mode and contrast images. For IPMC, the main reference frame was automatically selected for each cine, and subreference frames were selected in each respiratory cycle and sequentially registered toward the main reference frame. All other frames were sequentially registered toward the local subreference frame. Four OPMFs were developed and tested: subsample normalized correlation (NC), subsample sum of absolute differences, mean frame NC, and histogram. The frames that were most dissimilar to the OPMF reference frame using 1 of the 4 above criteria in each respiratory cycle were adaptively removed by thresholding against the low-pass filter of the similarity curve. Out-of-plane motion filter was quantitatively evaluated by an out-of-plane motion metric (OPMM) that measured normalized variance in the high-pass filtered TIC within the tumor region-of-interest with low OPMM being the goal. Results for IPMC and OPMF were qualitatively evaluated by 2 blinded observers who ranked the motion in the cines

  14. The multigap resistive plate chamber

    Energy Technology Data Exchange (ETDEWEB)

    Zeballos, E. Cerron [European Organization for Nuclear Research (CERN), Geneva (Switzerland); World Lab., Lausanne (Switzerland); Crotty, I. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Hatzifotiadou, D. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); World Lab., Lausanne (Switzerland); Valverde, J. Lamas [European Organization for Nuclear Research (CERN), Geneva (Switzerland); World Lab., Lausanne (Switzerland); Univ. Louis Pasteur, Strasbourg (France); Neupane, S. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); World Lab., Lausanne (Switzerland); Williams, M. C. S. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Zichichi, A. [Univ. of Bologna, Bologna (Italy)

    2015-02-03

    The paper describes the multigap resistive plate chamber (RPC). This is a variant of the wide gap RPC. However it has much improved time resolution, while keeping all the other advantages of the wide gap RPC design.

  15. MyPlate Daily Checklist

    Science.gov (United States)

    ... Price Tag Read the Food Label Kitchen Timesavers Cooking for Your Family Tasty & Low-Cost Recipes Sample 2-Week Menus Resources for Professionals MyPlate Tip Sheets Print Materials Infographics 5 Ways ...

  16. Plate shell structures of glass

    DEFF Research Database (Denmark)

    Bagger, Anne

    to their curved shape. A plate shell structure maintains a high stiffness-to-weight ratio, while facilitating the use of plane structural elements. The study focuses on using laminated glass panes for the load bearing facets. Various methods of generating a plate shell geometry are suggested. Together with Ghent......, such as facet size, imperfections, and connection characteristics. The critical load is compared to that of a similar, but smoothly curved, shell structure. Based on the investigations throughout the study, a set of guidelines for the structural design of plate shells of glass is proposed.......This thesis is a study of plate shell structures -- a type of shell structure with a piecewise plane geometry, organized so that the load bearing system is constituted by distributed in-plane forces in the facets. The high stiffness-to-weight ratio of smoothly curved shell structures is mainly due...

  17. License plate recognition (phase B).

    Science.gov (United States)

    2010-06-01

    License Plate Recognition (LPR) technology has been used for off-line automobile enforcement purposes. The technology has seen mixed success with correct reading rate as high as 60 to 80% depending on the specific application and environment. This li...

  18. Armor Plate Surface Roughness Measurements

    National Research Council Canada - National Science Library

    Stanton, Brian; Coburn, William; Pizzillo, Thomas J

    2005-01-01

    ...., surface texture and coatings) that could become important at high frequency. We measure waviness and roughness of various plates to know the parameter range for smooth aluminum and rolled homogenous armor (RHA...

  19. Dynamic analysis of the tether transportation system using absolute nodal coordinate formulation

    Science.gov (United States)

    Sun, Xin; Xu, Ming; Zhong, Rui

    2017-10-01

    Long space tethers are becoming a rising concern as an alternate way for transportation in space. It benefits from fuel economizing. This paper focuses on the dynamics of the tether transportation system, which consists of two end satellites connected by a flexible tether, and a movable vehicle driven by the actuator carried by itself. The Absolute Nodal Coordinate Formulation is applied to the establishment of the equation of motion, so that the influence caused by the distributed mass and elasticity of the tether is introduced. Moreover, an approximated method for accelerating the calculation of the generalized gravitational forces on the tether is proposed by substituting the volume integral every step into summation of finite terms. Afterwards, dynamic evolutions of such a system in different configurations are illustrated using numerical simulations. The deflection of the tether and the trajectory of the crawler during the transportation is investigated. Finally, the effect on the orbit of the system due to the crawler is revealed.

  20. Absolute continuity under time shift of trajectories and related stochastic calculus

    CERN Document Server

    Löbus, Jörg-Uwe

    2017-01-01

    The text is concerned with a class of two-sided stochastic processes of the form X=W+A. Here W is a two-sided Brownian motion with random initial data at time zero and A\\equiv A(W) is a function of W. Elements of the related stochastic calculus are introduced. In particular, the calculus is adjusted to the case when A is a jump process. Absolute continuity of (X,P) under time shift of trajectories is investigated. For example under various conditions on the initial density with respect to the Lebesgue measure, m, and on A with A_0=0 we verify \\frac{P(dX_{\\cdot -t})}{P(dX_\\cdot)}=\\frac{m(X_{-t})}{m(X_0)}\\cdot \\prod_i\\left|\

  1. OPERA Resistive Plate Chambers underground test results

    International Nuclear Information System (INIS)

    Bergnoli, A.; Brugnera, R.; Candela, A.; Carrara, E.; Ciesielski, R.; Dal Corso, F.; Degli Esposti, L.; Di Giovanni, A.; D'Incecco, M.; Di Troia, C.; Dusini, S.; Fanin, C.; Felici, G.; Gambarara, A.; Garfagnini, A.; Gatta, M.; Grianti, F.; Gustavino, C.; Lindozzi, M.; Longhin, A.; Mengucci, A.; Monacelli, P.; Paoloni, A.; Stanco, L.; Tatananni, E.; Terranova, F.; Spinetti, M.; Stipcevic, M.; Sugonyaev, V.; Terminiello, L.; Ventura, M.; Votano, L.

    2006-01-01

    The OPERA experiment [M. Guler et al., CERN/SPSC 2000-028, SPSC/P318, LNGS P25/2000, July 10, 2000; M. Guler et al., CERN/SPSC 2001-025, SPSC/M668, LNGS-EXP 30/2001 Add. 1/01, August 21, 2001] will study ν μ ->ν τ oscillations through τ appearance on the 732 Km long CERN to Gran Sasso baseline. The magnet yokes of the two muon spectrometers are instrumented with 44 layers of high resistivity bakelite Resistive Plate Chambers (RPCs) operated in streamer mode. Each layer covers about 70 m 2 . Four RPC planes were instrumented and the first tests were performed confirming a good behaviour of the installed RPCs in terms of intrinsic noise and operating currents. The measured noise maps agree with those obtained in the extensive quality tests performed at surface. Counting rates are below 20 Hz/m 2 . Single an multiple cosmic muon tracks were also reconstructed. The estimated efficiency is close to the geometrical limit and the very first measurements of the absolute and differential muon flux are in agreement with expectations

  2. Auditory working memory predicts individual differences in absolute pitch learning.

    Science.gov (United States)

    Van Hedger, Stephen C; Heald, Shannon L M; Koch, Rachelle; Nusbaum, Howard C

    2015-07-01

    Absolute pitch (AP) is typically defined as the ability to label an isolated tone as a musical note in the absence of a reference tone. At first glance the acquisition of AP note categories seems like a perceptual learning task, since individuals must assign a category label to a stimulus based on a single perceptual dimension (pitch) while ignoring other perceptual dimensions (e.g., loudness, octave, instrument). AP, however, is rarely discussed in terms of domain-general perceptual learning mechanisms. This is because AP is typically assumed to depend on a critical period of development, in which early exposure to pitches and musical labels is thought to be necessary for the development of AP precluding the possibility of adult acquisition of AP. Despite this view of AP, several previous studies have found evidence that absolute pitch category learning is, to an extent, trainable in a post-critical period adult population, even if the performance typically achieved by this population is below the performance of a "true" AP possessor. The current studies attempt to understand the individual differences in learning to categorize notes using absolute pitch cues by testing a specific prediction regarding cognitive capacity related to categorization - to what extent does an individual's general auditory working memory capacity (WMC) predict the success of absolute pitch category acquisition. Since WMC has been shown to predict performance on a wide variety of other perceptual and category learning tasks, we predict that individuals with higher WMC should be better at learning absolute pitch note categories than individuals with lower WMC. Across two studies, we demonstrate that auditory WMC predicts the efficacy of learning absolute pitch note categories. These results suggest that a higher general auditory WMC might underlie the formation of absolute pitch categories for post-critical period adults. Implications for understanding the mechanisms that underlie the

  3. Simple radiography by Imaging Plate

    Energy Technology Data Exchange (ETDEWEB)

    Takata, Shigeru; Koyama, Motoko; Tanizaki, Yoshiyuki [Tokyo Metropolitan Industrial Technology Research Insitute, Tokyo (Japan)

    1998-12-31

    Photo-stimulable phosphor is a material which emits luminescence by incitement of light. As useful photo-stimulable phosphor, alkali halide, like BaFBr: Eu, II - VI compound, like SrS: Eu and oxide, such as Al{sub 2}O{sub 3}: Care reported at present. Imaging Plate is a popular name of products, which is composed of thin layer of the phosphor fixed plastic plate. Photo-stimulable luminescence of Imaging Plate is emitted by scanning with narrow beam of incitement light. The light of luminescence is separated from incitement light by filter and it`s intensity is measured. The intensity of luminescence is proportional to absorbed dose of Imaging Plate from incident radiation. The map of luminescence intensity makes radiation image like radiograph taken by X-ray film. Reusability and usability of digital image are another advantage. The problem to solve of Imaging Plate are less resolution than X-ray film, expensive reading instrument and fading, which means decrease of luminescence intensity depend on elapse time after irradiation. High sensitivity of Imaging Plate makes possible of simple radiography by small radiation source. In Japanese law, sealed radioisotopes source less than 3.7 MBq can use without permission and register. If radiograph can be taken by sealed source less than 3.7 MBq, application of radiography is widely developed. So we try to take radiographs of some objects using Imaging Plate and sealed radioisotope sources under 3.7 MBq. As the result, useful radiographs are taken under conditions that exposure time is more than a few hours and distance between the source and the Plate is less than 30 cm. Quality of the image is poor than general radiograph by large radiation source. But the simple radiography taken by small source is of great value. (J.P.N.)

  4. Pulse plating of nickel deposits

    Energy Technology Data Exchange (ETDEWEB)

    Stimetz, C.J.; Stevenson, M.F.

    1980-02-01

    Pulse plated and conventional nickel deposits have been compared for differences in morphology, mechanical properties, and microstructure. The deposits were obtained from nickel sulfamate, nickel chloride, and Watts nickel plating solutions. No significant differences were found in the direct and pulse current deposits from the sulfamate and chloride solutions; however, significant differences in microstructure, yield strength, and microhardness were observed in deposits from the Watts nickel solution.

  5. Development of absolute intensity monitors and homogeneous irradiation system for synchrotron radiation at SPring-8

    International Nuclear Information System (INIS)

    Nariyama, N.; Taniguchi, S.; Kishi, N.; Ohnishi, S.; Odano, N.

    2003-01-01

    At SPring-8 of 8-GeV synchrotron radiation facility in Japan, high-intense monoenergetic photon beam up to hundred keV are available. For biological and medical researches, the absolute intensity monitor and homogeneous irradiation system are necessary. In this study, as intensity monitor two sizes of parallel-plate free-air ionization chambers were developed: plate distance of 8.5 cm for high-energy photons up to 190 keV and that of 0.42 cm for low-energy high-intense photons from undulator. Sizes of the larger chamber were determined considering electron loss using a Monte Carlo electron-photon transport code EGS4. For homogeneous irradiation method, a rotational linear-scanning method was proposed. An experiment was carried out at bending-magnet beamlines BL20B2 and 38B1 for high-energy photons. Dose measured with the chamber was compared to that of another free-air ionization chamber with 5-cm plate separation and a Si-PIN photodiode, which have been calibrated with a calorimeter. Agreement was confirmed from 30 keV up to 150 keV with a discrepancy less than 3%, which were independent of the beam size, intensity and injection position of the chamber. For intense photons from undulator, saturation measurement was made using the smaller chamber at BL46XU. Saturation was confirmed at 3 kV for 15- and 20-keV photons up to 10 12 photons/s. Using the larger chamber, fixed and Xθ -scanning irradiation methods were compared by irradiating thermoluminescent dosimeters at BL20B2, which can provide broad beam. As a function of the estimated exposure, all the signal data points became on the same straight line. Consequently, the Xθ -scanning method was found to be effective

  6. Early motion protocol for select Galeazzi fractures after radial shaft fixation.

    Science.gov (United States)

    Gwinn, David E; O'Toole, Robert V; Eglseder, W Andrew

    2010-01-01

    Galeazzi fractures traditionally are treated in long arm casts with the wrist fully supinated for 6 weeks after open reduction and internal fixation. Recent literature suggests that early motion can be permitted for a subset of Galeazzi fractures. Defining a safe postoperative protocol that allows immediate elbow motion, immediate platform weight bearing, and early wrist motion might decrease elbow morbidity, increase range of motion, and improve outcomes. A retrospective review of a prospectively collected database of 26 patients at a level I trauma center was conducted. Early motion protocol was assigned to patients who were radiographically and clinically stable after plate and screw fixation. Elbow flexion and platform weight bearing were allowed immediately; increased wrist rotation was allowed at 2-week intervals. Early motion of elbow and wrist seems to be safe during postoperative rehabilitation of repaired Galeazzi fractures. The postoperative protocol might maximize elbow and wrist range of motion.

  7. PEEK versus titanium locking plates for proximal humerus fracture fixation: a comparative biomechanical study in two- and three-part fractures.

    Science.gov (United States)

    Schliemann, Benedikt; Seifert, Robert; Theisen, Christina; Gehweiler, Dominic; Wähnert, Dirk; Schulze, Martin; Raschke, Michael J; Weimann, Andre

    2017-01-01

    The high rigidity of metal implants may be a cause of failure after fixation of proximal humerus fractures. Carbon fiber-reinforced polyetheretherketone (PEEK) plates with a modulus similar to human cortical bone may help to overcome this problem. The present study assesses the biomechanical behavior of a PEEK plate compared with a titanium locking plate. Unstable two- and three-part fractures were simulated in 12 pairs of cadaveric humeri and were fixed with either a PEEK or a titanium locking plate using a pairwise comparison. With an optical motion capture system, the stiffness, failure load, plate bending, and the relative motion at the bone-implant interface and at the fracture site were evaluated. The mean load to failure for two- and three-part fracture fixations was, respectively, 191 N (range 102-356 N) and 142 N (range 102-169 N) in the PEEK plate group compared with 286 N (range 191-395 N) and 258 N (range 155-366 N) in the titanium locking plate group. The PEEK plate showed significantly more bending in both the two- and three-part fractures (p PEEK plate showed lower fixation strength and increased motion at the bone-implant interface compared with a titanium locking plate.

  8. Absolute Dimensions of the Metallic-line Eclipsing Binary V501 Monocerotis

    Science.gov (United States)

    Torres, Guillermo; Sandberg Lacy, Claud H.; Pavlovski, Krešimir; Fekel, Francis C.; Muterspaugh, Matthew W.

    2015-11-01

    We report extensive high-resolution spectroscopic observations and V-band differential photometry of the slightly eccentric 7.02 day detached eclipsing binary V501 Mon (A6m+F0), which we use to determine its absolute dimensions to high precision (0.3% for the masses and 1.8% for the radii, or better). The absolute masses, radii, and temperatures are MA = 1.6455 ± 0.0043 M⊙, RA = 1.888 ± 0.029 R⊙, and {T}{{eff}}{{A}} = 7510 ± 100 K for the primary and MB = 1.4588 ± 0.0025 M⊙, RB = 1.592 ± 0.028 R⊙, and TeffB = 7000 ± 90 K for the secondary. Apsidal motion has been detected, to which General Relativity contributes approximately 70%. The primary star is found to be a metallic-line A star. A detailed chemical analysis of the disentangled spectra yields abundances for more than a dozen elements in each star. Based on the secondary, the system metallicity is near solar: [Fe/H] = +0.01 ± 0.06. Lithium is detected in the secondary but not in the primary. A comparison with current stellar evolution models shows a good match to the measured properties at an age of about 1.1 Gyr.

  9. OUTCOME OF LOCKING PLATES IN DISTAL TIBIA FRACTURES TREATMENT

    Directory of Open Access Journals (Sweden)

    Lokesh

    2016-05-01

    Full Text Available INTRODUCTION Most of these fractures except intra-articular fractures are treated with interlocking nail. 1,2 These nails are a boon for these fractures. But as the fracture nears to the joint stability the fracture fixation will be compromised due to malreduction and alignment, it leads to increased chances of delayed and nonunion. 3 Locking anatomical plates are evaluated for anatomical and relative stability fixation. Since then most intra and near intra-articular fractures are fixed with these plates with minimally invasive percutaneous plate osteosynthesis method, these plates have given excellent result 4 . But again these plates have some disadvantages 5 . This study is done to see the outcome of locking plates in distal tibia fracture. METHODS This study is done in the Department of Orthopaedics, Bangalore Medical College, Bangalore. This study is done from 2013 to 2015. 30 patients who came to outpatient department were treated with locking plates. All patients above 16 years having distal third tibia fracture are included. All open fractures except type 1 and elderly above 60 years and pathological fractures are excluded in our study. All patients were followed up for initial 5 months, thereafter, once in 3 months, for clinical and radiological evaluation of union status, knee range of motion, ankle range of motion and other complications. Assessment of the patient with functional recovery was done with American Orthopaedic Foot and Ankle Surgery(AOFAS 6 minimum 5 months after injury. RESULTS Majority of the patients are from age group 18-29 years (50%. Average age group was 30 years. Majority of the patients were males 80.6% (25. All fractures were closed fractures except 2 cases which are type 1. There were 12 cases of AO type A, 8 patients were AO type B and 10 patients were type C. Majority of the patients had fracture due to road traffic accidents, 74%. All fractures were united by the end of 20 weeks. There was delayed union in

  10. Absolute Navigation Information Estimation for Micro Planetary Rovers

    Directory of Open Access Journals (Sweden)

    Muhammad Ilyas

    2016-03-01

    Full Text Available This paper provides algorithms to estimate absolute navigation information, e.g., absolute attitude and position, by using low power, weight and volume Microelectromechanical Systems-type (MEMS sensors that are suitable for micro planetary rovers. Planetary rovers appear to be easily navigable robots due to their extreme slow speed and rotation but, unfortunately, the sensor suites available for terrestrial robots are not always available for planetary rover navigation. This makes them difficult to navigate in a completely unexplored, harsh and complex environment. Whereas the relative attitude and position can be tracked in a similar way as for ground robots, absolute navigation information, unlike in terrestrial applications, is difficult to obtain for a remote celestial body, such as Mars or the Moon. In this paper, an algorithm called the EASI algorithm (Estimation of Attitude using Sun sensor and Inclinometer is presented to estimate the absolute attitude using a MEMS-type sun sensor and inclinometer, only. Moreover, the output of the EASI algorithm is fused with MEMS gyros to produce more accurate and reliable attitude estimates. An absolute position estimation algorithm has also been presented based on these on-board sensors. Experimental results demonstrate the viability of the proposed algorithms and the sensor suite for low-cost and low-weight micro planetary rovers.

  11. Relative and absolute risk in epidemiology and health physics

    International Nuclear Information System (INIS)

    Goldsmith, R.; Peterson, H.T. Jr.

    1983-01-01

    The health risk from ionizing radiation commonly is expressed in two forms: (1) the relative risk, which is the percentage increase in natural disease rate and (2) the absolute or attributable risk which represents the difference between the natural rate and the rate associated with the agent in question. Relative risk estimates for ionizing radiation generally are higher than those expressed as the absolute risk. This raises the question of which risk estimator is the most appropriate under different conditions. The absolute risk has generally been used for radiation risk assessment, although mathematical combinations such as the arithmetic or geometric mean of both the absolute and relative risks, have also been used. Combinations of the two risk estimators are not valid because the absolute and relative risk are not independent variables. Both human epidemiologic studies and animal experimental data can be found to illustrate the functional relationship between the natural cancer risk and the risk associated with radiation. This implies that the radiation risk estimate derived from one population may not be appropriate for predictions in another population, unless it is adjusted for the difference in the natural disease incidence between the two populations

  12. Simulated earthquake ground motions

    International Nuclear Information System (INIS)

    Vanmarcke, E.H.; Gasparini, D.A.

    1977-01-01

    The paper reviews current methods for generating synthetic earthquake ground motions. Emphasis is on the special requirements demanded of procedures to generate motions for use in nuclear power plant seismic response analysis. Specifically, very close agreement is usually sought between the response spectra of the simulated motions and prescribed, smooth design response spectra. The features and capabilities of the computer program SIMQKE, which has been widely used in power plant seismic work are described. Problems and pitfalls associated with the use of synthetic ground motions in seismic safety assessment are also pointed out. The limitations and paucity of recorded accelerograms together with the widespread use of time-history dynamic analysis for obtaining structural and secondary systems' response have motivated the development of earthquake simulation capabilities. A common model for synthesizing earthquakes is that of superposing sinusoidal components with random phase angles. The input parameters for such a model are, then, the amplitudes and phase angles of the contributing sinusoids as well as the characteristics of the variation of motion intensity with time, especially the duration of the motion. The amplitudes are determined from estimates of the Fourier spectrum or the spectral density function of the ground motion. These amplitudes may be assumed to be varying in time or constant for the duration of the earthquake. In the nuclear industry, the common procedure is to specify a set of smooth response spectra for use in aseismic design. This development and the need for time histories have generated much practical interest in synthesizing earthquakes whose response spectra 'match', or are compatible with a set of specified smooth response spectra

  13. Local and global nonlinear dynamics of a parametrically excited rectangular symmetric cross-ply laminated composite plate

    International Nuclear Information System (INIS)

    Ye Min; Lu Jing; Zhang Wei; Ding Qian

    2005-01-01

    The present investigation deals with nonlinear dynamic behavior of a parametrically excited simply supported rectangular symmetric cross-ply laminated composite thin plate for the first time. The governing equation of motion for rectangular symmetric cross-ply laminated composite thin plate is derived by using von Karman equation. The geometric nonlinearity and nonlinear damping are included in the governing equations of motion. The Galerkin approach is used to obtain a two-degree-of-freedom nonlinear system under parametric excitation. The method of multiple scales is utilized to transform the second-order non-autonomous differential equations to the first-order averaged equations. Using numerical method, the averaged equations are analyzed to obtain the steady state bifurcation responses. The analysis of stability for steady state bifurcation responses in laminated composite thin plate is also given. Under certain conditions laminated composite thin plate may have two or multiple steady state bifurcation solutions. Jumping phenomenon occurs in the steady state bifurcation solutions. The chaotic motions of rectangular symmetric cross-ply laminated composite thin plate are also found by using numerical simulation. The results obtained here demonstrate that the periodic, quasi-periodic and chaotic motions coexist for a parametrically excited fore-edge simply supported rectangular symmetric cross-ply laminated composite thin plate under certain conditions

  14. Plate Coupling and Strain Partitioning in the Northeastern Caribbean

    Science.gov (United States)

    Manaker, D.; Calais, E.; Jansma, P.; Mattioli, G.

    2006-12-01

    Major strike-slip faults commonly found on the margin of overriding plates in oblique subduction zone settings facilitate the partitioning of strain into trench-parallel and trench-normal tectonics. Their development has been proposed to be controlled by factors such as convergence obliquity, basal tractions, magnitude of slab-pull force, or strength of interplate coupling. In the northeastern Caribbean, the direction of GPS velocities and earthquake slip vectors suggests low coupling along the Puerto Rico and Lesser Antilles trenches, but strong coupling to the west along the Hispaniola margin, while the convergence obliquity remains constant. Coincidentally, large strike-slip faults in the overriding plate only develop in Hispaniola, which is also the locus of the largest historical subduction earthquakes in the Caribbean (M8.0, 1946-53 sequence). We investigate interplate coupling at the Caribbean-North American plate boundary using a model that allows for block rotations and elastic strain accumulation on partially coupled faults. Model parameters (block rotations and coupling on interplate faults) are derived from an inversion of earthquake slip vectors and new GPS data covering Haiti, the Dominican Republic, Puerto Rico and the Virgin Islands, and the Lesser Antilles. We find that intraplate coupling is high in the western half of the domain, coincident with the development of large and fast-slipping strike-slip faults in the upper plate that partition the Carribean/North America plate motion, but low in its eastern half, along the Puerto Rico and Lesser Antilles subductions, that show little to no strain partitioning. This suggests that strain partitioning occur only if interplate coupling is large enough to effectively transfer shear stresses to the overriding plate.

  15. A STUDY ON PROXIMAL HUMERAL FRACTURES STABILISED WITH PHILOS PLATE

    Directory of Open Access Journals (Sweden)

    Praveen Sivakumar K

    2017-02-01

    Full Text Available BACKGROUND Techniques for treating complex proximal humeral fractures vary and include fixations using tension bands, percutaneous pins, bone suture, T-plates, intramedullary nails, double tubular plates, hemiarthroplasty, plant tan humerus fixator plates, Polaris nails and blade plates. Complications of these techniques include cutout or back out of the screws and plates, avascular necrosis, nonunion, malunion, nail migration, rotator cuff impairment and impingement syndromes. Insufficient anchorage from conventional implants may lead to early loosening and failure, especially in osteoporotic bones. In general, nonoperative treatment of displaced three and four-part fractures of the proximal humerus leads to poor outcome due to intraarticular nature of injury and inherent instability of the fragments. Comminuted fractures of the proximal humerus are at risk of fixation failure, screw loosening and fracture displacement. Open reduction and internal fixation with conventional plate and screws has been associated with unacceptably high incidence of screw pull out. PHILOS (the proximal humeral internal locking system plate is an internal fixation system that enables angled stabilisation with multiple interlocking screws for fractures of the proximal humerus. MATERIALS AND METHODS 30 patients with proximal humerus fractures who were admitted in the Department of Orthopaedics, Government General Hospital, Kakinada, during the period November 2014 - November 2016 were taken up for study according to inclusion criteria. All patients were treated with PHILOS plate. These proximal humerus fractures were classified according to Neer’s classification. Patients were followed up at 6 weeks, 12 weeks and 6 months’ interval. Functional outcomes for pain, range of motion and muscle power and function were assessed using the Constant-Murley scoring system. Collected data analysed with independent t-test and ANNOVA test. RESULTS The outcome of the study was 1

  16. Two peg spade plate for distal radius fractures A novel technique

    Directory of Open Access Journals (Sweden)

    Sharad M Hardikar

    2015-01-01

    Conclusions: The two peg volar spade plate provides a stable subchondral support in comminuted intraarticular fractures and maintains reduction in osteoporotic fractures of the distal radius. Early mobilization with this implant helps in restoring wrist motion and to prevent development of wrist stiffness.

  17. Modeling and Chaotic Dynamics of the Laminated Composite Piezoelectric Rectangular Plate

    Directory of Open Access Journals (Sweden)

    Minghui Yao

    2014-01-01

    Full Text Available This paper investigates the multipulse heteroclinic bifurcations and chaotic dynamics of a laminated composite piezoelectric rectangular plate by using an extended Melnikov method in the resonant case. According to the von Karman type equations, Reddy’s third-order shear deformation plate theory, and Hamilton’s principle, the equations of motion are derived for the laminated composite piezoelectric rectangular plate with combined parametric excitations and transverse excitation. The method of multiple scales and Galerkin’s approach are applied to the partial differential governing equation. Then, the four-dimensional averaged equation is obtained for the case of 1 : 3 internal resonance and primary parametric resonance. The extended Melnikov method is used to study the Shilnikov type multipulse heteroclinic bifurcations and chaotic dynamics of the laminated composite piezoelectric rectangular plate. The necessary conditions of the existence for the Shilnikov type multipulse chaotic dynamics are analytically obtained. From the investigation, the geometric structure of the multipulse orbits is described in the four-dimensional phase space. Numerical simulations show that the Shilnikov type multipulse chaotic motions can occur. To sum up, both theoretical and numerical studies suggest that chaos for the Smale horseshoe sense in motion exists for the laminated composite piezoelectric rectangular plate.

  18. Measuring Behavior using Motion Capture

    NARCIS (Netherlands)

    Fikkert, F.W.; van der Kooij, Herman; Ruttkay, Z.M.; van Welbergen, H.; Spink, A.J.; Ballintijn, M.R.; Bogers, N.D.; Grieco, F; Loijens, L.W.S.; Noldus, L.P.J.J.; Smit, G; Zimmerman, P.H.

    2008-01-01

    Motion capture systems, using optical, magnetic or mechanical sensors are now widely used to record human motion. Motion capture provides us with precise measurements of human motion at a very high recording frequency and accuracy, resulting in a massive amount of movement data on several joints of

  19. A retrospective comparison of four plate constructs for first metatarsophalangeal joint fusion: static plate, static plate with lag screw, locked plate, and locked plate with lag screw.

    Science.gov (United States)

    Hyer, Christopher F; Scott, Ryan T; Swiatek, Michael

    2012-01-01

    The primary treatment for progressive first metatarsophalangeal (MTP) joint arthritis is arthrodesis. Multiple fixation types have been used to accomplish fusion including plating. There have been no published articles reporting the outcomes of these 4 plate and/or screw constructs. We present our experience with 138 first MTP joint fusions using these constructs. A retrospective comparison and radiographic chart review of 132 patients (138 feet) was performed to compare different constructs in regards to successful union and time to fusion. All operations were performed by 4 fellowship-trained foot and ankle surgeons. The radiographs were independently read by 2 authors not involved in the index procedures. Radiographic fusion was determined by bridging cortices across the joint line. The mean time to union (in days) and rate of fusion were static plate: 59, 95%, static plate with lag screw: 56, 86%, locked plate: 66, 92%, and locked plate with lag screw: 53, 96%. There was not a statistically significant difference between the groups in regards to patient age, time to weight bearing, time to fusion, or rate of fusion. We report on the results of fusion comparing 4 different plate and/or screw constructs for first MTP joint fusion. The data reveal no significant difference in time to fusion or rate of fusion between static and locked plates, with or without a lag screw. Copyright © 2012 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Absolute marine gravimetry with matter-wave interferometry.

    Science.gov (United States)

    Bidel, Y; Zahzam, N; Blanchard, C; Bonnin, A; Cadoret, M; Bresson, A; Rouxel, D; Lequentrec-Lalancette, M F

    2018-02-12

    Measuring gravity from an aircraft or a ship is essential in geodesy, geophysics, mineral and hydrocarbon exploration, and navigation. Today, only relative sensors are available for onboard gravimetry. This is a major drawback because of the calibration and drift estimation procedures which lead to important operational constraints. Atom interferometry is a promising technology to obtain onboard absolute gravimeter. But, despite high performances obtained in static condition, no precise measurements were reported in dynamic. Here, we present absolute gravity measurements from a ship with a sensor based on atom interferometry. Despite rough sea conditions, we obtained precision below 10 -5  m s -2 . The atom gravimeter was also compared with a commercial spring gravimeter and showed better performances. This demonstration opens the way to the next generation of inertial sensors (accelerometer, gyroscope) based on atom interferometry which should provide high-precision absolute measurements from a moving platform.

  1. Adjustment and testing comparison of absolute gravimeters in November 2013

    Directory of Open Access Journals (Sweden)

    Alena Pešková

    2017-07-01

    Full Text Available This paper is focused on a comparison measurement processing of absolute gravimeters in 2013. The comparison deals with a number of various types of absolute gravimeters and includes also an absolute gravimeter from Geodetic observatory Pecný. Comparative measurements are performed to detect systematic errors of gravimeters. A result of processing is most likely value of a gravity and a systematic error of individual devices. Measured values are input to a adjustment with condition a sum of systematic errors is zero. A part of this process is also verification following output: (i value of a posteriori standard deviation, (ii size of corrections and (iii statistical significance of systematic errors. The results of adjustment are 15 gravity values on the reference places and 25 systematic errors of measuring instruments. Result shows that the presence of systematic errors in measurements is not statistically provable because the systematic errors are similarly sized as their standard deviation.

  2. Stress rotation across the Cascadia megathrust requires a weak subduction plate boundary at seismogenic depths

    Science.gov (United States)

    Li, Duo; McGuire, Jeffrey J.; Liu, Yajing; Hardebeck, Jeanne L.

    2018-03-01

    The Mendocino Triple Junction region is the most seismically active part of the Cascadia Subduction Zone. The northward moving Pacific plate collides with the subducting Gorda plate causing intense internal deformation within it. Here we show that the stress field rotates rapidly with depth across the thrust interface from a strike-slip regime within the subducting plate, reflecting the Pacific plate collision, to a thrust regime in the overriding plate. We utilize a dense focal mechanism dataset, including observations from the Cascadia Initiative ocean bottom seismograph experiment, to constrain the stress orientations. To quantify the implications of this rotation for the strength of the plate boundary, we designed an inversion that solves for the absolute stress tensors in a three-layer model subject to assumptions about the strength of the subducting mantle. Our results indicate that the shear stress on the plate boundary fault is likely no more than about ∼50 MPa at ∼20 km depth. Regardless of the assumed mantle strength, we infer a relatively weak megathrust fault with an effective friction coefficient of ∼0 to 0.2 at seismogenic depths. Such a low value for the effective friction coefficient requires a combination of high fluid pressures and/or fault-zone minerals with low inherent friction in the region where a great earthquake is expected in Cascadia.

  3. Morphologic and radiologic data of isolated vertebral end-plates under particular consideration of radiodensitometry

    International Nuclear Information System (INIS)

    Unflath, U.

    1979-01-01

    The intention was to find examination techniques for macroscopico-morphological diagnosis, for quantification of the concavity and methods for roentgenologico-densitometric analysis of vertebral end-plates. The following factors were used for macromorphologic diagnosis: osteophytes, ridge constitution, ridge transition, cribriform plate and concavity. The radiodensitometric analysis comprised investigation of bone density, anisotropy and ridge mineralisation. The specimen were radiographed on a mammograph together with calcium chloride solutions of increasing concentration. Statistically significant differences in the behaviour of basal and upper plates were not observed. With reference to the factors osteophytes and ridge constitution the basal plates seem to be morphologically more variable than the upper plates. It resulted that the features absolute concavity and concavity quotient are highly appropriate factors to document the constitution of the isolated vertebral end-plates. Also the features density, anisotropy and ridge mineralisation were found to be useful for documentation. The result of data correlation was that high concavity quotients are accompanied by macroscopically medium- to small-sized pores. Density and anisotropy of the overall profiles do not show correlation, but voluminous cribriform laminae tend to develop more inhomogenic structures. As to be expected, bone density increases with macroscopic fine porosity. The higher the concavity quotient is, the smaller are the values for density, ridge mineralisation and anisotropy. Thus a high degree of vertebral end-plate concavity indicates reduced bone density and lower mineral content. (orig./MG) [de

  4. Stress rotation across the Cascadia megathrust requires a weak subduction plate boundary at seismogenic depths

    Science.gov (United States)

    Li, Duo; McGuire, Jeffrey J.; Liu, Yajing; Hardebeck, Jeanne L.

    2018-01-01

    The Mendocino Triple Junction region is the most seismically active part of the Cascadia Subduction Zone. The northward moving Pacific plate collides with the subducting Gorda plate causing intense internal deformation within it. Here we show that the stress field rotates rapidly with depth across the thrust interface from a strike-slip regime within the subducting plate, reflecting the Pacific plate collision, to a thrust regime in the overriding plate. We utilize a dense focal mechanism dataset, including observations from the Cascadia Initiative ocean bottom seismograph experiment, to constrain the stress orientations. To quantify the implications of this rotation for the strength of the plate boundary, we designed an inversion that solves for the absolute stress tensors in a three-layer model subject to assumptions about the strength of the subducting mantle. Our results indicate that the shear stress on the plate boundary fault is likely no more than about ∼50 MPa at ∼20 km depth. Regardless of the assumed mantle strength, we infer a relatively weak megathrust fault with an effective friction coefficient of ∼0 to 0.2 at seismogenic depths. Such a low value for the effective friction coefficient requires a combination of high fluid pressures and/or fault-zone minerals with low inherent friction in the region where a great earthquake is expected in Cascadia.

  5. Modal radiation patterns of baffled circular plates and membranes.

    Science.gov (United States)

    Christiansen, Thomas Lehrmann; Hansen, Ole; Thomsen, Erik Vilain; Jensen, Jørgen Arendt

    2014-05-01

    The far field velocity potential and radiation pattern of baffled circular plates and membranes are found analytically using the full set of modal velocity profiles derived from the corresponding equation of motion. The derivation is valid for a plate or membrane subjected to an external excitation force, which is used as a sound receiver in any medium or as a sound transmitter in a gaseous medium. A general, concise expression is given for the radiation pattern of any mode of the membrane and the plate with arbitrary boundary conditions. Specific solutions are given for the four special cases of a plate with clamped, simply supported, and free edge boundary conditions as well as for the membrane. For all non-axisymmetric modes, the velocity potential along the axis of the radiator is found to be strictly zero. In the long wavelength limit, the radiation pattern of all axisymmetric modes approaches that of a monopole, while the non-axisymmetric modes exhibit multipole behavior. Numerical results are also given, demonstrating the implications of having non-axisymmetric excitation using both a point excitation with varying eccentricity and a homogeneous excitation acting on half of the circular radiator.

  6. Absolute and Relative Socioeconomic Health Inequalities across Age Groups.

    Directory of Open Access Journals (Sweden)

    Sander K R van Zon

    Full Text Available The magnitude of socioeconomic health inequalities differs across age groups. It is less clear whether socioeconomic health inequalities differ across age groups by other factors that are known to affect the relation between socioeconomic position and health, like the indicator of socioeconomic position, the health outcome, gender, and as to whether socioeconomic health inequalities are measured in absolute or in relative terms. The aim is to investigate whether absolute and relative socioeconomic health inequalities differ across age groups by indicator of socioeconomic position, health outcome and gender.The study sample was derived from the baseline measurement of the LifeLines Cohort Study and consisted of 95,432 participants. Socioeconomic position was measured as educational level and household income. Physical and mental health were measured with the RAND-36. Age concerned eleven 5-years age groups. Absolute inequalities were examined by comparing means. Relative inequalities were examined by comparing Gini-coefficients. Analyses were performed for both health outcomes by both educational level and household income. Analyses were performed for all age groups, and stratified by gender.Absolute and relative socioeconomic health inequalities differed across age groups by indicator of socioeconomic position, health outcome, and gender. Absolute inequalities were most pronounced for mental health by household income. They were larger in younger than older age groups. Relative inequalities were most pronounced for physical health by educational level. Gini-coefficients were largest in young age groups and smallest in older age groups.Absolute and relative socioeconomic health inequalities differed cross-sectionally across age groups by indicator of socioeconomic position, health outcome and gender. Researchers should critically consider the implications of choosing a specific age group, in addition to the indicator of socioeconomic position and

  7. Absolute and Relative Socioeconomic Health Inequalities across Age Groups.

    Science.gov (United States)

    van Zon, Sander K R; Bültmann, Ute; Mendes de Leon, Carlos F; Reijneveld, Sijmen A

    2015-01-01

    The magnitude of socioeconomic health inequalities differs across age groups. It is less clear whether socioeconomic health inequalities differ across age groups by other factors that are known to affect the relation between socioeconomic position and health, like the indicator of socioeconomic position, the health outcome, gender, and as to whether socioeconomic health inequalities are measured in absolute or in relative terms. The aim is to investigate whether absolute and relative socioeconomic health inequalities differ across age groups by indicator of socioeconomic position, health outcome and gender. The study sample was derived from the baseline measurement of the LifeLines Cohort Study and consisted of 95,432 participants. Socioeconomic position was measured as educational level and household income. Physical and mental health were measured with the RAND-36. Age concerned eleven 5-years age groups. Absolute inequalities were examined by comparing means. Relative inequalities were examined by comparing Gini-coefficients. Analyses were performed for both health outcomes by both educational level and household income. Analyses were performed for all age groups, and stratified by gender. Absolute and relative socioeconomic health inequalities differed across age groups by indicator of socioeconomic position, health outcome, and gender. Absolute inequalities were most pronounced for mental health by household income. They were larger in younger than older age groups. Relative inequalities were most pronounced for physical health by educational level. Gini-coefficients were largest in young age groups and smallest in older age groups. Absolute and relative socioeconomic health inequalities differed cross-sectionally across age groups by indicator of socioeconomic position, health outcome and gender. Researchers should critically consider the implications of choosing a specific age group, in addition to the indicator of socioeconomic position and health outcome

  8. Neural sensitivity to absolute and relative anticipated reward in adolescents.

    Directory of Open Access Journals (Sweden)

    Jatin G Vaidya

    Full Text Available Adolescence is associated with a dramatic increase in risky and impulsive behaviors that have been attributed to developmental differences in neural processing of rewards. In the present study, we sought to identify age differences in anticipation of absolute and relative rewards. To do so, we modified a commonly used monetary incentive delay (MID task in order to examine brain activity to relative anticipated reward value (neural sensitivity to the value of a reward as a function of other available rewards. This design also made it possible to examine developmental differences in brain activation to absolute anticipated reward magnitude (the degree to which neural activity increases with increasing reward magnitude. While undergoing fMRI, 18 adolescents and 18 adult participants were presented with cues associated with different reward magnitudes. After the cue, participants responded to a target to win money on that trial. Presentation of cues was blocked such that two reward cues associated with $.20, $1.00, or $5.00 were in play on a given block. Thus, the relative value of the $1.00 reward varied depending on whether it was paired with a smaller or larger reward. Reflecting age differences in neural responses to relative anticipated reward (i.e., reference dependent processing, adults, but not adolescents, demonstrated greater activity to a $1 reward when it was the larger of the two available rewards. Adults also demonstrated a more linear increase in ventral striatal activity as a function of increasing absolute reward magnitude compared to adolescents. Additionally, reduced ventral striatal sensitivity to absolute anticipated reward (i.e., the difference in activity to medium versus small rewards correlated with higher levels of trait Impulsivity. Thus, ventral striatal activity in anticipation of absolute and relative rewards develops with age. Absolute reward processing is also linked to individual differences in Impulsivity.

  9. An Examination of Upper Plate Aftershocks of the Tohoku-oki Earthquake: Are They Caused by a Long-term Change in the Dip of the Subducting Plate?

    Science.gov (United States)

    Oryan, B.; Buck, W. R.

    2017-12-01

    The Tohoku-oki earthquake was one of the strongest earthquakes ever recorded. 50-80 meters of lateral motion of the sloping seafloor resulted in a tsunami that exceeded predictions and caused one of the costliest natural disasters in history. It was also the first time extensional aftershocks were observed in the upper plate over a region as wide as 250km. Inspired by these findings, researchers found similar upper plate extensional earthquakes after reexamining seismic data from past earthquakes that had also produced large tsunamis. Such extensional aftershocks are difficult to explain in terms of standard subduction models. Most models assume that the dip of the subducting plate remains constant with time. However, geological evidence indicates that the dip angle of the subducting plate changes. We hypothesize that a reduction in the dip angle of the subducting plate can cause upper plate extensional earthquakes. This change in dip angle adds extensional bending stress to the upper plate. During an inter-seismic period, the interface is `locked' causing regional compression that prevents the release of extensional energy. Relief of compressional stresses during a megathrust event can trigger the release of the accumulated extensional energy, explaining why extensional earthquakes were observed after some megathrust events. Numerical models will be used to test our hypothesis. First, we will model long term subduction with a nearly constant dip angle. Then, we will impose a `mantle wind' to reduce the dip angle of the subducting plate. Eventually, we will model a full seismic cycle of the subduction resulting in a megathrust event. The generation of extensional earthquakes in the upper plate of our model following the megathrust event will allow us to determine whether a causal link exists between these earthquakes and a reduction in the dip angle of the subducting plate.

  10. Influence of environmental information in natural scenes and the effects of motion adaptation on a fly motion-sensitive neuron during simulated flight

    Directory of Open Access Journals (Sweden)

    Thomas W. Ullrich

    2014-12-01

    Full Text Available Gaining information about the spatial layout of natural scenes is a challenging task that flies need to solve, especially when moving at high velocities. A group of motion sensitive cells in the lobula plate of flies is supposed to represent information about self-motion as well as the environment. Relevant environmental features might be the nearness of structures, influencing retinal velocity during translational self-motion, and the brightness contrast. We recorded the responses of the H1 cell, an individually identifiable lobula plate tangential cell, during stimulation with image sequences, simulating translational motion through natural sceneries with a variety of differing depth structures. A correlation was found between the average nearness of environmental structures within large parts of the cell's receptive field and its response across a variety of scenes, but no correlation was found between the brightness contrast of the stimuli and the cell response. As a consequence of motion adaptation resulting from repeated translation through the environment, the time-dependent response modulations induced by the spatial structure of the environment were increased relatively to the background activity of the cell. These results support the hypothesis that some lobula plate tangential cells do not only serve as sensors of self-motion, but also as a part of a neural system that processes information about the spatial layout of natural scenes.

  11. Delamination, upper plate extension, and plate margin complexity

    Science.gov (United States)

    Ueda, Kosuke; Gerya, Taras; Willett, Sean

    2017-04-01

    We investigate the syn- and post-subduction margin evolution with respect to extension, lithospheric removal, and magmatic and topographic consequences by employing 3D geodynamic models. In all experiments, regions of extended partial melting are overlain by up to 3 km high plateaus. There is complex geometric entanglement between upper mantle, partially molten rocks, and lithosphere, which is thermally eroded, over hundreds of kilometers across the plate contact. A complex lithosphere-asthenosphere-boundary features elongated anomalies at scales of few tens to hundred kilometers. First-order, synthetic seismic anomaly patterns, based on thermodynamic velocities which are tabulated for model p,T conditions, are accordingly complex. Passive margin geometry variations in the lower plate effect consistent and inherited differences in dynamic evolution. Promontories along the margin tend to trigger three stages of evolution: 1) a magmatic arc; 2) a lower plate, eduction-like exhumation of buried continental crust in domal patterns of few tens of km wavelength; and subsequently, 3) the formation of extended zones on the upper plate which lack a lithospheric mantle, undergo partial extension, and feature lower crustal melting. Slab break-off is consistently favoured in locations where the lower plate margin is relatively recessed. Concerning the classical removal mechanisms, transitions and co-evolution between delamination, convective thinning, and upper-plate extension are gradual and these modes are not mutually exclusive. Almost complete mixed-mode removal and extension can be compared to the Aegean. Slab window formation by margin geometry variation produces characteristic uplift patterns that are comparable to the Apennines, where higher uplift rates could be a consequence of incipient necking of the slab below central Calabria.

  12. Clinical application of absolute ethanol as an embolizing material

    International Nuclear Information System (INIS)

    Park, Jae Hyung; Chang, Kee Hyun; Han, Man Chung

    1982-01-01

    Transcatheter infusion of absolute ethanol was applied clinically in 3 cases of artificial embolization: 25 yrs old female with bilateral renal angiomyolipoma, 19 yrs old female with right paralumbar liposarcoma and 25 yrs old male with hypernephroma of right kidney. Selective or subselective manual infusion was made and 9 to 22 cc of pure ethanol was delivered in a speed of 1 to 2 cc per second. The sclerosing effect of absolute ethanol was potent. However, all 3 cases revealed mild post-embolization syndrome

  13. Absolute Stability Analysis of a Phase Plane Controlled Spacecraft

    Science.gov (United States)

    Jang, Jiann-Woei; Plummer, Michael; Bedrossian, Nazareth; Hall, Charles; Jackson, Mark; Spanos, Pol

    2010-01-01

    Many aerospace attitude control systems utilize phase plane control schemes that include nonlinear elements such as dead zone and ideal relay. To evaluate phase plane control robustness, stability margin prediction methods must be developed. Absolute stability is extended to predict stability margins and to define an abort condition. A constrained optimization approach is also used to design flex filters for roll control. The design goal is to optimize vehicle tracking performance while maintaining adequate stability margins. Absolute stability is shown to provide satisfactory stability constraints for the optimization.

  14. Absolute gain measurement by the image method under mismatched condition

    Science.gov (United States)

    Lee, Richard Q.; Baddour, Maurice F.

    1987-01-01

    Purcell's image method for measuring the absolute gain of an antenna is particularly attractive for small test antennas. The method is simple to use and utilizes only one antenna with a reflecting plane to provide an image for the receiving antenna. However, the method provides accurate results only if the antenna is matched to its waveguide. In this paper, a waveguide junction analysis is developed to determine the gain of an antenna under mismatched condition. Absolute gain measurements for two standard gain horn antennas have been carried out. Experimental results agree closely with published data.

  15. Absolute and conditional convergence within Sonora state municipalities, 1989- 2004

    Directory of Open Access Journals (Sweden)

    Joaquín Bracamontes Neváre

    2008-07-01

    Full Text Available This paper tries to identify the existence of convergence, absolut as muchas conditional, for the municipalities that conform the state of Sonora. Taking as abase the methodologic excercise of Mankiw, Romer and Weill (1992 that considersthe first model of Solow (1956 and makes an extension of it including thehuman capital, evidence shows that there is no tendency for poor municipalitiesto grow more quickly than rich municipalities, which means that there is no processof convergence –nor absolute or conditional– in the municipalities of Sonora,independently of the development layer in which these are classified: municipalitieswith high, average or low development.

  16. Total synthesis and absolute configuration of the marine norditerpenoid xestenone.

    Science.gov (United States)

    Ota, Koichiro; Kurokawa, Takao; Kawashima, Etsuko; Miyaoka, Hiroaki

    2009-11-24

    Xestenone is a marine norditerpenoid found in the northeastern Pacific sponge Xestospongia vanilla. The relative configuration of C-3 and C-7 in xestenone was determined by NOESY spectral analysis. However the relative configuration of C-12 and the absolute configuration of this compound were not determined. The authors have now achieved the total synthesis of xestenone using their developed one-pot synthesis of cyclopentane derivatives employing allyl phenyl sulfone and an epoxy iodide as a key step. The relative and absolute configurations of xestenone were thus successfully determined by this synthesis.

  17. Total Synthesis and Absolute Configuration of the Marine Norditerpenoid Xestenone

    Directory of Open Access Journals (Sweden)

    Hiroaki Miyaoka

    2009-11-01

    Full Text Available Xestenone is a marine norditerpenoid found in the northeastern Pacific sponge Xestospongia vanilla. The relative configuration of C-3 and C-7 in xestenone was determined by NOESY spectral analysis. However the relative configuration of C-12 and the absolute configuration of this compound were not determined. The authors have now achieved the total synthesis of xestenone using their developed one-pot synthesis of cyclopentane derivatives employing allyl phenyl sulfone and an epoxy iodide as a key step. The relative and absolute configurations of xestenone were thus successfully determined by this synthesis.

  18. Structural Analysis of Plate Based Tensegrity Structures

    DEFF Research Database (Denmark)

    Hald, Frederik; Kirkegaard, Poul Henning; Damkilde, Lars

    2013-01-01

    Plate tensegrity structures combine tension cables with a cross laminated timber plate and can then form e.g. a roof structure. The topology of plate tensegrity structures is investigated through a parametric investigation. Plate tensegrity structures are investigated, and a method...

  19. Use of savart plates in grating interferometers.

    Science.gov (United States)

    Peek, T H

    1971-05-01

    An analysis is given of Savart plates for arbitrary angles between the optic axis and the plate normal. Conoscopic interference patterns of thin Savart plates cut nearly parallel to the optic axis are shown and the use of such plates combined with diffraction gratings is discussed.

  20. Ground motion predictions

    International Nuclear Information System (INIS)

    Loux, P.C.

    1969-01-01

    Nuclear generated ground motion is defined and then related to the physical parameters that cause it. Techniques employed for prediction of ground motion peak amplitude, frequency spectra and response spectra are explored, with initial emphasis on the analysis of data collected at the Nevada Test Site (NTS). NTS postshot measurements are compared with pre-shot predictions. Applicability of these techniques to new areas, for example, Plowshare sites, must be questioned. Fortunately, the Atomic Energy Commission is sponsoring complementary studies to improve prediction capabilities primarily in new locations outside the NTS region. Some of these are discussed in the light of anomalous seismic behavior, and comparisons are given showing theoretical versus experimental results. In conclusion, current ground motion prediction techniques are applied to events off the NTS. Predictions are compared with measurements for the event Faultless and for the Plowshare events, Gasbuggy, Cabriolet, and Buggy I. (author)

  1. Large deflection analysis of laminated composite plates resting on nonlinear elastic foundations by the method of discrete singular convolution

    International Nuclear Information System (INIS)

    Baltacioglu, A.K.; Civalek, O.; Akgoez, B.; Demir, F.

    2011-01-01

    This paper presents nonlinear static analysis of a rectangular laminated composite thick plate resting on nonlinear two-parameter elastic foundation with cubic nonlinearity. The plate formulation is based on first-order shear deformation theory (FSDT). The governing equation of motion for a rectangular laminated composite thick plate is derived by using the von Karman equation. The nonlinear static deflections of laminated plates on elastic foundation are investigated using the discrete singular convolution method. The effects of foundation and geometric parameters of plates on nonlinear deflections are investigated. The validity of the present method is demonstrated by comparing the present results with those available in the literature. - Highlights: → Large deflection analysis of laminated composite plates are investigated. → As foundation, nonlinear elastic models have been used firstly. → The effects of three-parameter foundation are investigated in detail.

  2. Plating on some difficult-to-plate metals and alloys

    International Nuclear Information System (INIS)

    Dini, J.W.; Johnson, H.R.

    1980-02-01

    Electrodeposition of coatings on metals such as beryllium, beryllium-copper, Kovar, lead, magnesium, thorium, titanium, tungsten, uranium, zirconium, and their alloys can be problematic. This is due in most cases to a natural oxide surface film that readily reforms after being removed. The procedures we recommend for plating on these metals rely on replacing the oxide film with a displacement coating, or etching to allow mechanical keying between the substrate and plated deposit. The effectiveness of the procedures is demonstrated by interface bond strengths found in ring-shear and conical-head tensile tests

  3. Refining plate reconstructions of the North Atlantic and Ellesmerian domains

    Science.gov (United States)

    Shephard, Grace E.; Abdelmalak, Mansour M.; Buiter, Susanne; Piepjohn, Karsten; Jones, Morgan; Torsvik, Trond; Faleide, Jan Inge; Gaina, Carmen

    2017-04-01

    Located at the intersection of major tectonic plates, the North Atlantic and western Arctic domains have experienced both widespread and localized deformation since the Paleozoic. In conventional tectonic reconstructions, the plates of Greenland, Eurasia and North America are assumed to be rigid. However, prior to the onset of seafloor spreading, rifting lithosphere experiences significant thinning that is usually not accounted for. This leads to significant (in excess of 300 km in places) over- and under-laps between conjugate continent-ocean boundaries, an incomplete history of basin evolution, and loose correlations between climatic, volcanic, oceanographic and, geologic events. Furthermore, a handful of alternative regional reconstructions now exist, which predict different timings, rates and locations of relative motion and associated deformation. Assumptions of reference crustal thicknesses and the nature of lower crustal bodies, as well as the location of basin hinge lines have to-date not yet been incorporated into a consistent regional kinematic model. Notably, the alternative models predict varying episodes of compression or quiescence, not just orthogonal or oblique rifting. Here, we present new temporal and spatial-dependent results related to (1) the dominant rifting episodes across the North Atlantic (Carboniferous, Late Permian, Late Jurassic-Early Cenozoic and Late Cretaceous-Paleogene), and (2) restoration of compression and strike-slip motion between northern Greenland, Ellesmere Island (North America) and Spitsbergen (Eurasia) related to the Eurekan Orogeny. We achieve this by integrating a series of conjugate seismic profiles, calculated stretching factors, dated volcanic events, structural mapping and mass-balanced restorations into a global plate motion model via GPlates software. We also test alternative models of rift velocities (as kinematic boundary conditions) with 2-D lithosphere and mantle numerical models, and explore the importance of

  4. Leap Motion development essentials

    CERN Document Server

    Spiegelmock, Mischa

    2013-01-01

    This book is a fast-paced guide with practical examples that aims to help you understand and master the Leap Motion SDK.This book is for developers who are either involved in game development or who are looking to utilize Leap Motion technology in order to create brand new user interaction experiences to distinguish their products from the mass market. You should be comfortable with high-level languages and object-oriented development concepts in order to get the most out of this book.

  5. Ship Roll Motion Control

    DEFF Research Database (Denmark)

    Perez, Tristan; Blanke, Mogens

    2010-01-01

    The technical feasibility of roll motion control devices has been amply demonstrated for over 100 years. Performance, however, can still fall short of expectations because of deciencies in control system designs, which have proven to be far from trivial due to fundamental performance limitations....... This tutorial paper presents an account of the development of various ship roll motion control systems and the challenges associated with their design. The paper discusses how to assess performance, the applicability of dierent models, and control methods that have been applied in the past....

  6. Discovery of Japan’s Oldest Photographic Plates of a Starfield

    Science.gov (United States)

    Watanabe, Jun-ichi; Sasaki, Goro; Nakagiri, Masao; Ohshima, Norio

    2015-08-01

    The Public Outreach and Archive Office in NAOJ has been inspecting as many as 20,000 old photographic plates, which were found in a pile of cardboard cartons. In the course of their inspections, we have discovered 437 plates recorded from the end of the 19th century to the beginning of the 20th century. This was the first era in which observations were recorded using photographic plates in Japan.Most of the plates were obtained by using the Brashear astrograph at Azabubu in the 19th century. The oldest photographic plate was marked (delete ‘as’) No.13 and was recorded on March 5, 1899. We also found a number of historically important plates; among these are images of the first minor planet “TOKIO” that was detected in Japan and named after our country, and of a star 61 Cyg, with a large proper motion.We have long known that Tokyo Observatory of Tokyo Imperial University began its observations at Azabu. However, for many years, everyone believed that all the plates and observational instruments were lost in the chaos following the Great Kanto earthquake (1923) and in a fire that damaged Tokyo Observatory’s main building during the World War II, events that took place before and after the Observatory’s move to Mitaka. We made a catalogue of these plates and will present some statistics along with our effort for archives in our observatory.

  7. Free vibration analysis of smart annular FGM plates integrated with piezoelectric layers

    Science.gov (United States)

    Ebrahimi, F.; Rastgoo, A.

    2008-02-01

    In this paper, a nonlinear free vibration analysis of a thin annular functionally graded (FG) plate integrated with two uniformly distributed actuator layers made of piezoelectric (PZT4) material on the top and bottom surfaces of the annular FG plate is presented based on Kirchhoff plate theory. The material properties of the functionally graded core plate are assumed to be graded in the thickness direction according to the power law distribution in terms of the volume fractions of the constituents and the distribution of the electric potential field along the thickness direction of piezoelectric layers is simulated by a sinusoidal function such that the Maxwell static electricity equation is satisfied. The differential equations of motion are solved analytically for various boundary conditions of the plate. The analytical solutions are derived and validated by comparing the obtained resonant frequencies of the piezoelectric coupled FG annular plate with those of an isotropic core plate. In a numerical study the emphasis is placed on investigating the effect of varying the gradient index of the FG plate on the free vibration characteristics of the structure. Also the good agreement between the results of this paper and those of the finite element (FE) analyses validated the presented approach.

  8. Parametric study on nonlinear vibration of composite truss core sandwich plate with internal resonance

    International Nuclear Information System (INIS)

    Chen, Jia Nen; Liu, Jun; Zhang, Wei; Yao, Ming Hui; Sun, Min

    2016-01-01

    Nonlinear vibrations of carbon fiber reinforced composite sandwich plate with pyramidal truss core are investigated. The governing equation of motion for the sandwich plate is derived by using a Zig-Zag theory under consideration of geometrically nonlinear. The natural frequencies of sandwich plates with different dimensions are calculated and compared with those obtained from the classic laminated plate theory and Reddy's third-order shear deformation plate theory. The frequency responses and waveforms of the sandwich plate when 1:3 internal resonance occurs are obtained, and the characteristics of the internal resonance are discussed. The influences of layer number of face sheet, strut radius, core height and inclination angle on the nonlinear responses of the sandwich plate are analyzed. The results demonstrate that the strut radius and inclination angle mainly affect the resonance frequency band of the sandwich plate, and the layer number and core height not only influence the resonance frequency band but also significantly affect the response amplitude

  9. General analytical approach for sound transmission loss analysis through a thick metamaterial plate

    International Nuclear Information System (INIS)

    Oudich, Mourad; Zhou, Xiaoming; Badreddine Assouar, M.

    2014-01-01

    We report theoretically and numerically on the sound transmission loss performance through a thick plate-type acoustic metamaterial made of spring-mass resonators attached to the surface of a homogeneous elastic plate. Two general analytical approaches based on plane wave expansion were developed to calculate both the sound transmission loss through the metamaterial plate (thick and thin) and its band structure. The first one can be applied to thick plate systems to study the sound transmission for any normal or oblique incident sound pressure. The second approach gives the metamaterial dispersion behavior to describe the vibrational motions of the plate, which helps to understand the physics behind sound radiation through air by the structure. Computed results show that high sound transmission loss up to 72 dB at 2 kHz is reached with a thick metamaterial plate while only 23 dB can be obtained for a simple homogeneous plate with the same thickness. Such plate-type acoustic metamaterial can be a very effective solution for high performance sound insulation and structural vibration shielding in the very low-frequency range

  10. Effect of Fluid Viscoelasticity on Turbulence and Large-Scale Vortices behind Wall-Mounted Plates

    Directory of Open Access Journals (Sweden)

    Takahiro Tsukahara

    2014-03-01

    Full Text Available Direct numerical simulations of turbulent viscoelastic fluid flows in a channel with wall-mounted plates were performed to investigate the influence of viscoelasticity on turbulent structures and the mean flow around the plate. The constitutive equation follows the Giesekus model, valid for polymer or surfactant solutions, which are generally capable of reducing the turbulent frictional drag in a smooth channel. We found that turbulent eddies just behind the plates in viscoelastic fluid decreased in number and in magnitude, but their size increased. Three pairs of organized longitudinal vortices were observed downstream of the plates in both Newtonian and viscoelastic fluids: two vortex pairs were behind the plates and the other one with the longest length was in a plate-free area. In the viscoelastic fluid, the latter vortex pair in the plate-free area was maintained and reached the downstream rib, but its swirling strength was weakened and the local skin-friction drag near the vortex was much weaker than those in the Newtonian flow. The mean flow and small spanwise eddies were influenced by the additional fluid force due to the viscoelasticity and, moreover, the spanwise component of the fluid elastic force may also play a role in the suppression of fluid vortical motions behind the plates.

  11. Spray formation during the vertical impact of a flat plate on a quiescent water surface

    Science.gov (United States)

    Wang, An; Duncan, James H.

    2017-11-01

    Spay formation during the impact of a rigid flat plate (122 cm by 38 cm) on a quiescent water surface is studied experimentally. The plate is mounted on a carriage that is driven by an electric servo motor that can slam the plate vertically into the water surface under feedback-controlled motions at various speeds. The long edges of the plate are kept horizontal and the short edges are set at various angles (roll angles) with respect to the quiescent water surface. A laser light sheet is created in a vertical plane at the middle of the long edges of the plate. The evolution of the spray within the light sheet is measured with a cinematic laser induced fluorescence technique. Two types of spray are found with nonzero roll angles. The first type is a cloud of high-speed droplets and ligaments that are generated when the plate's leading edge impacts the free surface. The second type is a thin water sheet that is connected to the trailing edge of the plate via a crater and is formed after the trailing edge moves below the local water level. In a reference frame moving with the plate, the profiles of the crater collapse when scaled with a power law function of time. The characteristics of the two types of spray are found to be affected by both the roll angle and the impact velocity. The support of the Office of Naval Research is gratefully acknowledged.

  12. Leading and trailing edges of moving plates record contrasting thermal, mechanical, tectonic and stratigraphic histories

    Science.gov (United States)

    Bodur, O. F.; Rey, P. F.; Müller, D.

    2017-12-01

    At the transition between thick continental plates and thinner adjacent oceanic plates, the deep-seated corner of the related lithospheric mantle step is exposed to thermomechanical erosion during plate motion, and lateral variations in lithospheric thickness and temperature at these regions initiate a corner flow. Here, we present a suite of thermomechanical numerical experiments to document and characterize the mechanical and thermal evolution of the trailing and leading edge of a moving plate. We show that the geometry of the trailing and leading margins of plates evolve by a combination of thermomechanical accretion or erosion, respectively. This drives subsidence and uplift, part of which is dynamically driven by the mantle flow, and the remainder is an isostatic response to the change in structure and/or temperature of the margins. Interestingly, leading and trailing edges record contrasting tectonic histories with magnitudes of extension/contraction measurable after tens of million years of plate motion. Our numerical experiments predict different sediment supply and accommodation space, along with different tectonics and heat flow for different margins during sedimentation. These suggest that measurable differences in tectonics and stratigraphy should exist between the trailing and leading margins of moving continents. This new modelling approach will provide new insights into fundamental differences in the evolution of Australian passive margin basins regarding their subsidence, thermal evolution and stratigraphy depending on their location along the southern, trailing edge or the northern leading edge of the continent.

  13. Generation of plate tectonics with two-phase grain-damage and pinning: Source-sink model and toroidal flow

    Science.gov (United States)

    Bercovici, David; Ricard, Yanick

    2013-03-01

    The grain-damage and pinning mechanism of Bercovici and Ricard (2012) for lithospheric shear-localization is employed in two-dimensional flow calculations to test its ability to generate toroidal (strike-slip) motion and influence plate evolution. This mechanism posits that damage to the interface between phases in a polycrystalline material like peridotite (composed primarily of olivine and pyroxene) increases the number of small Zener pinning surfaces, which then constrain mineral grains to ever smaller sizes, regardless of creep mechanism. This effect allows a self-softening feedback in which damage and grain-reduction can co-exist with a grain-size dependent diffusion creep rheology; moreover, grain growth and weak-zone healing are greatly impeded by Zener pinning thereby leading to long-lived relic weak zones. The fluid dynamical calculations employ source-sink driven flow as a proxy for convective poloidal flow (upwelling/downwelling and divergent/convergent motion), and the coupling of this flow with non-linear rheological mechanisms excites toroidal or strike-slip motion. The numerical experiments show that pure dislocation-creep rheology, and grain-damage without Zener pinning (as occurs in a single-phase assemblages) permit only weak localization and toroidal flow; however, the full grain-damage with pinning readily allows focussed localization and intense, plate-like toroidal motion and strike-slip deformation. Rapid plate motion changes are also tested with abrupt rotations of the source-sink field after a plate-like configuration is developed; the post-rotation flow and material property fields retain memory of the original configuration for extensive periods, leading to suboptimally aligned plate boundaries (e.g., strike-slip margins non-parallel to plate motion), oblique subduction, and highly localized, weak and long lived acute plate-boundary junctions such as at what is observed at the Aleutian-Kurile intersection. The grain-damage and pinning

  14. Deflection and trapping of a counter-rotating vortex pair by a flat plate

    Science.gov (United States)

    Nitsche, Monika

    2017-12-01

    The interaction of a counter-rotating vortex pair (dipole) with a flat plate in its path is studied numerically. The vortices are initially separated by a distance D (dipole size) and placed far upstream of a plate of length L . The plate is centered on the dipole path and inclined relative to it at an incident angle βi. At first, the plate is held fixed in place. The vortices approach the plate, travel around it, and then leave as a dipole with unchanged velocity but generally a different travel direction, measured by a transmitted angle βt. For certain plate angles the transmitted angle is highly sensitive to changes in the incident angle. The sensitivity increases as the dipole size decreases relative to the plate length. In fact, for sufficiently small values of D /L , singularities appear: near critical values of βi, the dipole trajectory undergoes a topological discontinuity under changes of βi or D /L . The discontinuity is characterized by a jump in the winding number of one vortex around the plate, and in the time that the vortices take to leave the plate. The jumps occur repeatedly in a self-similar, fractal fashion, within a region near the critical values of βi, showing the existence of incident angles that trap the vortices, which never leave the plate. The number of these trapping regions increases as the parameter D /L decreases, and the dependence of the motion on βi becomes increasingly complex. The simulations thus show that even in this apparently simple scenario, the inviscid dynamics of a two-point-vortex system interacting with a stationary wall is surprisingly rich. The results are then applied to separate an incoming stream of dipoles by an oscillating plate.

  15. Absolute Value Inequalities: High School Students' Solutions and Misconceptions

    Science.gov (United States)

    Almog, Nava; Ilany, Bat-Sheva

    2012-01-01

    Inequalities are one of the foundational subjects in high school math curricula, but there is a lack of academic research into how students learn certain types of inequalities. This article fills part of the research gap by presenting the findings of a study that examined high school students' methods of approaching absolute value inequalities,…

  16. Absolute measurements of chlorine Cl+ cation single photoionization cross section

    NARCIS (Netherlands)

    Hernandez, E. M.; Juarez, A. M.; Kilcoyne, A. L. D.; Aguilar, A.; Hernandez, L.; Antillon, A.; Macaluso, D.; Morales-Mori, A.; Gonzalez-Magana, O.; Hanstorp, D.; Covington, A. M.; Davis, V.; Calabrese, D.; Hinojosa, G.

    The photoionization of Cl+ leading to Cl2+ was measured in the photon energy range of 19.5-28.0 eV. A spectrum with a photon energy resolution of 15 meV normalized to absolute cross-section measurements is presented. The measurements were carried out by merging a Cl+ ion beam with a photon beam of

  17. Europe's Other Poverty Measures: Absolute Thresholds Underlying Social Assistance

    Science.gov (United States)

    Bavier, Richard

    2009-01-01

    The first thing many learn about international poverty measurement is that European nations apply a "relative" poverty threshold and that they also do a better job of reducing poverty. Unlike the European model, the "absolute" U.S. poverty threshold does not increase in real value when the nation's standard of living rises,…

  18. Mechanism for an absolute parametric instability of an inhomogeneous plasma

    Science.gov (United States)

    Arkhipenko, V. I.; Budnikov, V. N.; Gusakov, E. Z.; Romanchuk, I. A.; Simonchik, L. V.

    1984-05-01

    The structure of plasma oscillations in a region of parametric spatial amplification has been studied experimentally for the first time. A new mechanism for an absolute parametric instability has been observed. This mechanism operates when a pump wave with a spatial structure more complicated than a plane wave propagates through a plasma which is inhomogeneous along more than one dimension.

  19. Global Absolute Poverty: Behind the Veil of Dollars

    NARCIS (Netherlands)

    Moatsos, M.

    2015-01-01

    The global absolute poverty rates of the World Bank demonstrate a continued decline of poverty in developing countries between 1983 and 2012. However, the methodology applied to derive these results has received extensive criticism by scholars for requiring the application of PPP exchange rates and

  20. Global Absolute Poverty: Behind the Veil of Dollars

    NARCIS (Netherlands)

    Moatsos, M.

    2017-01-01

    The widely applied “dollar-a-day” methodology identifies global absolute poverty as declining precipitously since the early 80’s throughout the developing world. The methodological underpinnings of the “dollar-a-day” approach have been questioned in terms of adequately representing equivalent

  1. An improved generalized Newton method for absolute value equations.

    Science.gov (United States)

    Feng, Jingmei; Liu, Sanyang

    2016-01-01

    In this paper, we suggest and analyze an improved generalized Newton method for solving the NP-hard absolute value equations [Formula: see text] when the singular values of A exceed 1. We show that the global and local quadratic convergence of the proposed method. Numerical experiments show the efficiency of the method and the high accuracy of calculation.

  2. Multipliers for the absolute Euler summability of Fourier series

    Indian Academy of Sciences (India)

    Springer Verlag Heidelberg #4 2048 1996 Dec 15 10:16:45

    (Math. Sci.), Vol. 111, No. 2, May 2001, pp. 203–219. Printed in India. Multipliers for the absolute Euler summability of Fourier series. PREM CHANDRA. School of Studies in Mathematics, Vikram University, Ujjain 456 010, India. MS received 30 December 1999; revised 30 October 2000. Abstract. In this paper, the author ...

  3. Predicting accurate absolute binding energies in aqueous solution

    DEFF Research Database (Denmark)

    Jensen, Jan Halborg

    2015-01-01

    Recent predictions of absolute binding free energies of host-guest complexes in aqueous solution using electronic structure theory have been encouraging for some systems, while other systems remain problematic. In this paper I summarize some of the many factors that could easily contribute 1-3 kcal...

  4. Planck absolute entropy of a rotating BTZ black hole

    Indian Academy of Sciences (India)

    S. M. Jawwad Riaz

    2018-03-06

    Mar 6, 2018 ... Abstract. In this paper, the Planck absolute entropy and the Bekenstein–Smarr formula of the rotating. Banados–Teitelboim–Zanelli (BTZ) black hole are presented via a complex thermodynamical system con- tributed by its inner and outer horizons. The redefined entropy approaches zero as the ...

  5. Multipliers for the Absolute Euler Summability of Fourier Series

    Indian Academy of Sciences (India)

    In this paper, the author has investigated necessary and sufficient conditions for the absolute Euler summability of the Fourier series with multipliers. These conditions are weaker than those obtained earlier by some workers. It is further shown that the multipliers are best possible in certain sense.

  6. 20 CFR 404.1205 - Absolute coverage groups.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Absolute coverage groups. 404.1205 Section 404.1205 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL OLD-AGE, SURVIVORS AND DISABILITY...) Employees of a State's political subdivision performing services in connection with that subdivision's...

  7. Absolute luminosity measurements with the LHCb detector at the LHC

    CERN Document Server

    Aaij, R; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amhis, Y; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Arrabito, L; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Bailey, D S; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, C; Bauer, Th; Bay, A; Bediaga, I; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Brisbane, S; Britsch, M; Britton, T; Brook, N H; Brown, H; Büchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Caicedo Carvajal, J M; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Charles, M; Charpentier, Ph; Chiapolini, N; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Collins, P; Constantin, F; Conti, G; Contu, A; Cook, A; Coombes, M; Corti, G; Cowan, G A; Currie, R; D'Almagne, B; D'Ambrosio, C; David, P; De Bonis, I; De Capua, S; De Cian, M; De Lorenzi, F; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Deissenroth, M; Del Buono, L; Deplano, C; Deschamps, O; Dettori, F; Dickens, J; Dijkstra, H; Diniz Batista, P; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Eames, C; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisele, F; Eisenhardt, S; Ekelhof, R; Eklund, L; Elsasser, Ch; d'Enterria, D G; Esperante Pereira, D; Estève, L; Falabella, A; Fanchini, E; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Fernandez Albor, V; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Frank, M; Frei, C; Frosini, M; Furcas, S; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garnier, J-C; Garofoli, J; Garra Tico, J; Garrido, L; Gaspar, C; Gauvin, N; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Gregson, S; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Haefeli, G; Haen, C; Haines, S C; Hampson, T; Hansmann-Menzemer, S; Harji, R; Harnew, N; Harrison, J; Harrison, P F; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hofmann, W; Holubyev, K; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Huston, R S; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Imong, J; Jacobsson, R; Jaeger, A; Jahjah Hussein, M; Jans, E; Jansen, F; Jaton, P; Jean-Marie, B; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kandybei, S; Karacson, M; Karbach, T M; Keaveney, J; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Knecht, M; Koblitz, S; Koppenburg, P; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kruzelecki, K; Kucharczyk, M; Kukulak, S; Kumar, R; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leroy, O; Lesiak, T; Li, L; Li Gioi, L; Lieng, M; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Luisier, J; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Magnin, J; Malde, S; Mamunur, R M D; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinez Santos, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Maynard, B; Mazurov, A; McGregor, G; McNulty, R; Mclean, C; Meissner, M; Merk, M; Merkel, J; Messi, R; Miglioranzi, S; Milanes, D A; Minard, M-N; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Musy, M; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nardulli, J; Nasteva, I; Nedos, M; Needham, M; Neufeld, N; Nguyen-Mau, C; Nicol, M; Nies, S; Niess, V; Nikitin, N; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B; Palacios, J; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Paterson, S K; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perego, D L; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petrella, A; Petrolini, A; Pie Valls, B; Pietrzyk, B; Pilar, T; Pinci, D; Plackett, R; Playfer, S; Plo Casasus, M; Polok, G; Poluektov, A; Polycarpo, E; Popov, D; Popovici, B; Potterat, C; Powell, A; du Pree, T; Prisciandaro, J; Pugatch, V; Puig Navarro, A; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Rinnert, K; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodrigues, F; Rodriguez Perez, P; Rogers, G J; Roiser, S; Romanovsky, V; Rouvinet, J; Ruf, T; Ruiz, H; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salzmann, C; Sannino, M; Santacesaria, R; Santamarina Rios, C; Santinelli, R; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schleich, S; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M -H; Schwemmer, R; Sciubba, A; Seco, M; Semennikov, A; Senderowska, K; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shao, B; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Skottowe, H P; Skwarnicki, T; Smith, A C; Smith, N A; Sobczak, K; Soler, F J P; Solomin, A; Soomro, F; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Styles, N; Subbiah, V K; Swientek, S; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Topp-Joergensen, S; Tran, M T; Tsaregorodtsev, A; Tuning, N; Ubeda Garcia, M; Ukleja, A; Urquijo, P; Uwer, U; Vagnoni, V; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; Velthuis, J J; Veltri, M; Vervink, K; Viaud, B; Videau, I; Vilasis-Cardona, X; Visniakov, J; Vollhardt, A; Voong, D; Vorobyev, A; Voss, H; Wacker, K; Wandernoth, S; Wang, J; Ward, D R; Webber, A D; Websdale, D; Whitehead, M; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wishahi, J; Witek, M; Witzeling, W; Wotton, S A; Wyllie, K; Xie, Y; Xing, F; Yang, Z; Young, R; Yushchenko, O; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhong, L; Zverev, E; Zvyagin, A

    2012-01-01

    Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In addition to the classic ``van der Meer scan'' method a novel technique has been developed which makes use of direct imaging of the individual beams using beam-gas and beam-beam interactions. This beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. The results of the two methods have comparable precision and are in good agreement. Combining the two methods, an overall precision of 3.5\\% in the absolute lumi...

  8. Dominated operators, absolutely summing operators and the strict ...

    African Journals Online (AJOL)

    b(X;E) be the space of all E-valued bounded continuous functions on X, equipped with the strict topology β. We study dominated and absolutely summing operators T : Cb(X;E) → F. We derive that if X is a locally compact Hausdorff space and E ...

  9. NIST Stars: Absolute Spectrophotometric Calibration of Vega and Sirius

    Science.gov (United States)

    Deustua, Susana; Woodward, John T.; Rice, Joseph P.; Brown, Steven W.; Maxwell, Stephen E.; Alberding, Brian G.; Lykke, Keith R.

    2018-01-01

    Absolute flux calibration of standard stars, traceable to SI (International System of Units) standards, is essential for 21st century astrophysics. Dark energy investigations that rely on observations of Type Ia supernovae and precise photometric redshifts of weakly lensed galaxies require a minimum accuracy of 0.5 % in the absolute color calibration. Studies that aim to address fundamental stellar astrophysics also benefit. In the era of large telescopes and all sky surveys well-calibrated standard stars that do not saturate and that are available over the whole sky are needed. Significant effort has been expended to obtain absolute measurements of the fundamental standards Vega and Sirius (and other stars) in the visible and near infrared, achieving total uncertainties between1% and 3%, depending on wavelength, that do not meet the needed accuracy. The NIST Stars program aims to determine the top-of-the-atmosphere absolute spectral irradiance of bright stars to an uncertainty less than 1% from a ground-based observatory. NIST Stars has developed a novel, fully SI-traceable laboratory calibration strategy that will enable achieving the desired accuracy. This strategy has two key components. The first is the SI-traceable calibration of the entire instrument system, and the second is the repeated spectroscopic measurement of the target star throughout the night. We will describe our experimental strategy, present preliminary results for Vega and Sirius and an end-to-end uncertainty budget

  10. Confirmation of the absolute configuration of (−)-aurantioclavine

    KAUST Repository

    Behenna, Douglas C.

    2011-04-01

    We confirm our previous assignment of the absolute configuration of (-)-aurantioclavine as 7R by crystallographically characterizing an advanced 3-bromoindole intermediate reported in our previous synthesis. This analysis also provides additional support for our model of enantioinduction in the palladium(II)-catalyzed oxidative kinetic resolution of secondary alcohols. © 2010 Elsevier Ltd. All rights reserved.

  11. DESIGN AND CONSTRUCTION OF AN ABSOLUTE GRAVITY METER

    African Journals Online (AJOL)

    An absolute gravimeter which has been designed and constructed consists of a timing circuit which measures the time a body takes to fall between two points separated by a known distance. The time of fall and the known distance are used to calculate the acceleration of gravity at the point of experimentation.

  12. Absolutely continuous spectrum and spectral transition for some ...

    Indian Academy of Sciences (India)

    Absolutely continuous spectrum and spectral transition for some continuous random operators. M KRISHNA. Institute of Mathematical Sciences, Taramani, Chennai 600 113, India. E-mail: krishna@imsc.res.in. MS received 28 February 2010; revised 6 June 2011. Dedicated to Barry Simon for his 65th birthday. Abstract.

  13. Frequency Windows of Absolute Negative Conductance in Josephson Junctions

    OpenAIRE

    Machura, L.; Kostur, M.; Talkner, P.; Hanggi, P.; Luczka, J.

    2007-01-01

    We report on anomalous conductance in a resistively and capacitively shunted Josephson junction which is simultaneously driven by ac and dc currents. The dependence of the voltage across the junction on the frequency of the ac current shows windows of absolute negative conductance regimes, i.e. for a positive (negative) dc current, the voltage is negative (positive).

  14. Relative versus Absolute Stimulus Control in the Temporal Bisection Task

    Science.gov (United States)

    de Carvalho, Marilia Pinhiero; Machado, Armando

    2012-01-01

    When subjects learn to associate two sample durations with two comparison keys, do they learn to associate the keys with the short and long samples (relational hypothesis), or with the specific sample durations (absolute hypothesis)? We exposed 16 pigeons to an ABA design in which phases A and B corresponded to tasks using samples of 1 s and 4 s,…

  15. Use of absolute lymphocyte count or neutrophil ingestion rate of ...

    African Journals Online (AJOL)

    The present study was designed to evaluate absolute lymphocyte count or neutrophil ingestion rate of NBT as alternative indices to CD4+ T cell count in the management of HIV/AIDS subjects. 158 adult participants (male = 70, female = 88) were recruited for the study and grouped as: (i) Symptomatic HIV subjects with or ...

  16. Necessity and sufficiency conditions for the absolute null ...

    African Journals Online (AJOL)

    We are inspired by the works of Chukwu [1], Eke [2], Schinterdorf and Barmish [4] to unveil necessary and sufficient conditions for the absolute null controllability of a linear delay perturbed system with zero in the domain of null controllability. Journal of the Nigerian Association of Mathematical Physics Vol. 10 2006: pp. 549- ...

  17. Absolute Stability of Discrete-Time Systems with Delay

    Directory of Open Access Journals (Sweden)

    Medina Rigoberto

    2008-01-01

    Full Text Available We investigate the stability of nonlinear nonautonomous discrete-time systems with delaying arguments, whose linear part has slowly varying coefficients, and the nonlinear part has linear majorants. Based on the "freezing" technique to discrete-time systems, we derive explicit conditions for the absolute stability of the zero solution of such systems.

  18. DOES ABSOLUTE SYNONYMY EXIST IN OWERE-IGBO?

    African Journals Online (AJOL)

    USER

    or emotional overtones, etc. These are explained below: A. Contextual Differences: One of the implications of absolute synonymy is that it must be possible for synonyms to be used interchangeably in all sentence contexts. But our analyses of the sentences above as given by native speakers indicated that there are some ...

  19. The Absolute and the Relative Dimensions of Constitutional Rights

    Czech Academy of Sciences Publication Activity Database

    Alexy, Robert

    2017-01-01

    Roč. 37, č. 1 (2017), s. 31-47 ISSN 0143-6503 Keywords : constitutional rights * judicial review * proportionality Subject RIV: AG - Legal Sciences OBOR OECD: Law Impact factor: 1.242, year: 2016 https://academic.oup.com/ojls/article/37/1/31/2669583/The-Absolute-and-the-Relative-Dimensions-of

  20. Absolute parametric instability in a nonuniform plane plasma ...

    Indian Academy of Sciences (India)

    The paper reports an analysis of the effect of spatial plasma nonuniformity on absolute parametric instability (API) of electrostatic waves in magnetized plane waveguides subjected to an intense high-frequency (HF) electric field using the separation method. In this case the effect of strong static magnetic field is considered.

  1. Absolute parametric instability in a nonuniform plane plasma ...

    Indian Academy of Sciences (India)

    Abstract. The paper reports an analysis of the effect of spatial plasma nonuniformity on absolute parametric instability (API) of electrostatic waves in magnetized plane waveguides subjected to an intense high-frequency (HF) electric field using the separation method. In this case the effect of strong static magnetic field is ...

  2. Absolute intensity calibration for ECE measurements on EAST

    International Nuclear Information System (INIS)

    Liu Yong; Liu Xiang; Zhao Hailin

    2014-01-01

    In this proceeding, the results of the in-situ absolute intensity calibration for ECE measurements on EAST are presented. A 32-channel heterodyne radiometer system and a Michelson interferometer on EAST have been calibrated independently, and preliminary results from plasma operation indicate a good agreement between the electron temperature profiles obtained with different systems. (author)

  3. Fabricating the absolute fake: America in contemporary pop culture

    NARCIS (Netherlands)

    Kooijman, J.

    2008-01-01

    Onze wereld wordt gedomineerd door de Amerikaanse popcultuur. Fabricating the Absolute Fake onderzoekt de dynamiek van Amerikanisering aan de hand van hedendaagse films, televisieprogramma's en popsterren die reflecteren op de vraag wat het betekent om Amerikaan in een mondiale popcultuur te zijn.

  4. On quantum harmonic oscillator being subjected to absolute ...

    Indian Academy of Sciences (India)

    On quantum harmonic oscillator being subjected to absolute potential state. SWAMI NITYAYOGANANDA. Ramakrishna Mission Ashrama, R.K. Beach, Visakhapatnam 530 003, India. E-mail: nityayogananda@gmail.com. MS received 1 May 2015; accepted 6 May 2016; published online 3 December 2016. Abstract.

  5. Partial sums of arithmetical functions with absolutely convergent ...

    Indian Academy of Sciences (India)

    For an arithmetical function f with absolutely convergent Ramanujan expansion, we derive an asymptotic formula for the ∑ n ≤ N f(n)$ with explicit error term. As a corollary we obtain new results about sum-of-divisors functions and Jordan's totient functions.

  6. Partial sums of arithmetical functions with absolutely convergent ...

    Indian Academy of Sciences (India)

    , Chennai 600 113, India. E-mail: biswajyoti@imsc.res.in. MS received 9 May 2015; revised 9 July 2015. Abstract. For an arithmetical function f with absolutely convergent Ramanujan expansion, we derive an asymptotic formula for the sum. ∑.

  7. [The anatomical plates of Antommarchi].

    Science.gov (United States)

    Dumaitre, P

    1981-09-01

    Mascagni, professor of anatomy in Florence, died in the same town in 1815, leaving manuscripts and drawings for an intended publication of a comprehensive complete anatomy with life-size figures. His prosector, Antommarchi, prepared the publication but was meanwhile called to Saint Helena. He left, taking with him three copies of Mascagni's plates. When he returned, he published these plates, printed from lithographs, under his own name in a monumental work which appeared from 1823 to 1826 under the title of: Planches anatomiques du corps humain exécutées d'après les dimensions naturelles.

  8. A world in motion

    Energy Technology Data Exchange (ETDEWEB)

    Boynton, J.A. [SAE, Warrendale, PA (United States)

    1994-12-31

    A World in Motion is a physical science curriculum supplement for grades four, five, and six which responds to the need to promote and teach sound science and mathematics concepts. Using the A World in Motion kits, teachers work in partnership with practicing engineer or scientists volunteers to provide students with fun, exciting, and relevant hands-on science and math experiences. During the A World in Motion experience, students work together in {open_quotes}Engineering Design Teams{close_quotes} exploring physics concepts through a series of activities. Each student is assigned a role as either a facilities engineer, development engineer, test engineer, or project engineer and is given responsibilities paralleling those of engineers in industry. The program culminates in a {open_quotes}Design Review{close_quotes} where students can communicate their results, demonstrate their designs, and receive recognition for their efforts. They are given a chance to take on responsibility and build self-esteem. Since January 1991, over 12,000 volunteers engineers have been involved with the program, with a distribution of 20,000 A World in Motion kit throughout the U.S. and Canada.

  9. MotionsFloorball

    DEFF Research Database (Denmark)

    Vorup, Jacob; Seidelin, Kåre

    Med denne "opskriftsbog" er I nu klar til at begynde med MotionsFloorball. Ingen vellykket middagsret tilbereder som bekendt sig selv - de vigtigste ingredienser til et succesfuldt forløb er vilje og handlingskraft. Tilsættes værktøjerne og vidensdelen fra denne bog, er der dog ikke langt fra tanke...

  10. Superluminal motion (review)

    Science.gov (United States)

    Malykin, G. B.; Romanets, E. A.

    2012-06-01

    Prior to the development of Special Relativity, no restrictions were imposed on the velocity of the motion of particles and material bodies, as well as on energy transfer and signal propagation. At the end of the 19th century and the beginning of the 20th century, it was shown that a charge that moves at a velocity faster than the speed of light in an optical medium, in particular, in vacuum, gives rise to impact radiation, which later was termed the Vavilov-Cherenkov radiation. Shortly after the development of Special Relativity, some researchers considered the possibility of superluminal motion. In 1923, the Soviet physicist L.Ya. Strum suggested the existence of tachyons, which, however, have not been discovered yet. Superluminal motions can occur only for images, e.g., for so-called "light spots," which were considered in 1972 by V.L. Ginzburg and B.M. Bolotovskii. These spots can move with a superluminal phase velocity but are incapable of transferring energy and information. Nevertheless, these light spots may induce quite real generation of microwave radiation in closed waveguides and create the Vavilov-Cherenkov radiation in vacuum. In this work, we consider various paradoxes, illusions, and artifacts associated with superluminal motion.

  11. A Harmonic Motion Experiment

    Science.gov (United States)

    Gluck, P.; Krakower, Zeev

    2010-01-01

    We present a unit comprising theory, simulation and experiment for a body oscillating on a vertical spring, in which the simultaneous use of a force probe and an ultrasonic range finder enables one to explore quantitatively and understand many aspects of simple and damped harmonic motions. (Contains 14 figures.)

  12. Algebraic Description of Motion

    Science.gov (United States)

    Davidon, William C.

    1974-01-01

    An algebraic definition of time differentiation is presented and used to relate independent measurements of position and velocity. With this, students can grasp certain essential physical, geometric, and algebraic properties of motion and differentiation before undertaking the study of limits. (Author)

  13. Semilinear stochastic equations in a Hilbert space with a fractional Brownian motion

    Czech Academy of Sciences Publication Activity Database

    Duncan, T. E.; Maslowski, Bohdan; Pasik-Duncan, B.

    2009-01-01

    Roč. 40, č. 6 (2009), s. 2286-2315 ISSN 0036-1410 R&D Projects: GA ČR GA201/07/0237 Institutional research plan: CEZ:AV0Z10190503 Keywords : semilinear stochastic equations * fractional Brownian motion * stochastic partial differential equations * absolute continuity of measures Subject RIV: BA - General Mathematics Impact factor: 1.649, year: 2009

  14. Cenozoic Plate tectonic history of the northern Venezuela-Trinidad Area

    Science.gov (United States)

    Erlich, Robert N.; Barrett, S. F.

    1990-02-01

    Geological and geophysical data, coupled with recent plate tectonic reconstructions, suggest that the Cenozoic geologic history of the northern Venezuela-Trinidad area has been dominated by strike-slip displacement of discrete crustal blocks. Allochthonous terranes within the area include metavolcanic rocks of the Cretaceous Villa de Cura Group and metamorphic rocks of the Precambrian to Cretaceous Cordillera de la Costa. A relatively competent crustal block (Margarita Block) is defined by an outline around the metamorphic basement of Margarita Island, the Araya/Paria peninsula, the Northern Range of Trinidad, and Tobago Island. Reconstruction of the Margarita Block to its original position requires at least partial closure of the Falcon Basin, closure of the Bonaire and Cariaco basins, and restoration of about 50 km of motion on both the Oca and Bocono faults. Post middle Eocene eastward translation of the Caribbean plate caused eastward motion of the Margarita Block. A minor change in relative plate motion during the late Oligocene or early Miocene produced a right step in the Moron fault, forming the Cariaco pull-apart basin and El Pilar fault zone. Maximum offset on El Pilar fault is estimated to be no more than 125 km, though displacement along the entire fault zone may have been greater. Transpressional stresses between the Caribbean plate and northern South America caused folding of the Serrania del Interior of Venezuela and the Central Range of Trinidad. Eastward migration of transpressional stresses at the southeastern corner of the Caribbean-South American plate boundary is being accommodated by formation of oblique thrusts, transpressive anticlines, and downwarping of the crust. Bouguer gravity data suggest that Jurassic-aged Atlantic oceanic crust is being depressed as the Caribbean plate expands into the Demerara Plateau area. This study suggests that the faults and transtensional/transpressional/compressional structures identified in this study are

  15. Standardization approaches in absolute quantitative proteomics with mass spectrometry.

    Science.gov (United States)

    Calderón-Celis, Francisco; Encinar, Jorge Ruiz; Sanz-Medel, Alfredo

    2017-07-31

    Mass spectrometry-based approaches have enabled important breakthroughs in quantitative proteomics in the last decades. This development is reflected in the better quantitative assessment of protein levels as well as to understand post-translational modifications and protein complexes and networks. Nowadays, the focus of quantitative proteomics shifted from the relative determination of proteins (ie, differential expression between two or more cellular states) to absolute quantity determination, required for a more-thorough characterization of biological models and comprehension of the proteome dynamism, as well as for the search and validation of novel protein biomarkers. However, the physico-chemical environment of the analyte species affects strongly the ionization efficiency in most mass spectrometry (MS) types, which thereby require the use of specially designed standardization approaches to provide absolute quantifications. Most common of such approaches nowadays include (i) the use of stable isotope-labeled peptide standards, isotopologues to the target proteotypic peptides expected after tryptic digestion of the target protein; (ii) use of stable isotope-labeled protein standards to compensate for sample preparation, sample loss, and proteolysis steps; (iii) isobaric reagents, which after fragmentation in the MS/MS analysis provide a final detectable mass shift, can be used to tag both analyte and standard samples; (iv) label-free approaches in which the absolute quantitative data are not obtained through the use of any kind of labeling, but from computational normalization of the raw data and adequate standards; (v) elemental mass spectrometry-based workflows able to provide directly absolute quantification of peptides/proteins that contain an ICP-detectable element. A critical insight from the Analytical Chemistry perspective of the different standardization approaches and their combinations used so far for absolute quantitative MS-based (molecular and

  16. Towards absolute laser spectroscopic CO2 isotope ratio measurements

    Science.gov (United States)

    Anyangwe Nwaboh, Javis; Werhahn, Olav; Ebert, Volker

    2017-04-01

    Knowledge of isotope composition of carbon dioxide (CO2) in the atmosphere is necessary to identify sources and sinks of this key greenhouse gas. In the last years, laser spectroscopic techniques such as cavity ring-down spectroscopy (CRDS) and tunable diode laser absorption spectroscopy (TDLAS) have been shown to perform accurate isotope ratio measurements for CO2 and other gases like water vapour (H2O) [1,2]. Typically, isotope ratios are reported in literature referring to reference materials provided by e.g. the International Atomic Energy Agency (IAEA). However, there could be some benefit if field deployable absolute isotope ratio measurement methods were developed to address issues such as exhausted reference material like the Pee Dee Belemnite (PDB) standard. Absolute isotope ratio measurements would be particularly important for situations where reference materials do not even exist. Here, we present CRDS and TDLAS-based absolute isotope ratios (13C/12C ) in atmospheric CO2. We demonstrate the capabilities of the used methods by measuring CO2 isotope ratios in gas standards. We compare our results to values reported for the isotope certified gas standards. Guide to the expression of uncertainty in measurement (GUM) compliant uncertainty budgets on the CRDS and TDLAS absolute isotope ratio measurements are presented, and traceability is addressed. We outline the current impediments in realizing high accuracy absolute isotope ratio measurements using laser spectroscopic methods, propose solutions and the way forward. Acknowledgement Parts of this work have been carried out within the European Metrology Research Programme (EMRP) ENV52 project-HIGHGAS. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union. References [1] B. Kühnreich, S. Wagner, J. C. Habig,·O. Möhler, H. Saathoff, V. Ebert, Appl. Phys. B 119:177-187 (2015). [2] E. Kerstel, L. Gianfrani, Appl. Phys. B 92, 439-449 (2008).

  17. Large-Scale Present-Day Plate Boundary Deformations in the Eastern Hemisphere Determined from VLBI Data: Implications for Plate Tectonics and Indian Ocean Growth

    Science.gov (United States)

    Akilan, A.; Abdul Azeez, K. K.; Schuh, H.; Yuvraaj, N.

    2015-10-01

    The dynamics of the planet Earth are manifestations of diverse plate tectonic processes which have been occurring since the Archean period of the Earth's evolution and continue to deform the plate boundaries. Very long baseline interferometry (VLBI) is an efficient space geodetic method that enables precise measurement of plate motion and associated deformations. We analyze here VLBI measurements made during a period of approximately three decades at five locations on the Eastern hemisphere of the globe, which are geographically distributed over five continents (plates) around the Indian Ocean. Computed rate of change of baseline length show the deformation pattern and its rate at the boundaries between the major tectonic plates constituting the Eastern hemisphere of the Earth. The African (Nubian) and Antarctic plates are moving apart at 13.5 mm/year, which is mostly attributed to spreading of the South West Indian Ridge. Similarly, spreading of 59.0 mm/year is observed for the South East Indian Ridge that separates the Antarctic and Australian plates. Shortening at the rate of 3.9 mm/year is estimated across the subduction boundary between Africa (Nubia) and Eurasia. Similar convergence is evident between the Australian and Sunda blocks (of the Eurasian plate). The associated deformation of -54.8 mm/year seems to be chiefly accommodated along the Banda arc system, where the Australian plate is subducting under the Sunda block. VLBI sites within the Eurasian plate, Wettzell in Germany, and Seshan on the South China block, are moving apart at 3.6 mm/year. This relative motion between locations on the same plate is interpreted as a result of the deformation process along a large strike-slip fault, which is identified as the Western boundary of the South China block. Expansion of the Indian Ocean, at +91.5 m2/year, is also estimated from the rate of deformation estimated within the five baselines studied here. From the Hurst exponent values, which are indicators of

  18. Hidden Earthquake Potential in Plate Boundary Transition Zones

    Science.gov (United States)

    Furlong, Kevin P.; Herman, Matthew; Govers, Rob

    2017-04-01

    Plate boundaries can exhibit spatially abrupt changes in their long-term tectonic deformation (and associated kinematics) at triple junctions and other sites of changes in plate boundary structure. How earthquake behavior responds to these abrupt tectonic changes is unclear. The situation may be additionally obscured by the effects of superimposed deformational signals - juxtaposed short-term (earthquake cycle) kinematics may combine to produce a net deformational signal that does not reflect intuition about the actual strain accumulation in the region. Two examples of this effect are in the vicinity of the Mendocino triple junction (MTJ) along the west coast of North America, and at the southern end of the Hikurangi subduction zone, New Zealand. In the region immediately north of the MTJ, GPS-based observed crustal displacements (relative to North America (NAm)) are intermediate between Pacific and Juan de Fuca (JdF) motions. With distance north, these displacements rotate to become more aligned with JdF - NAm displacements, i.e. to motions expected along a coupled subduction interface. The deviation of GPS motions from the coupled subduction interface signal near the MTJ has been previously interpreted to reflect clock-wise rotation of a coastal, crustal block and/or reduced coupling at the southern Cascadia margin. The geologic record of crustal deformation near the MTJ reflects the combined effects of northward crustal shortening (on geologic time scales) associated with the MTJ Crustal Conveyor (Furlong and Govers, 1999) overprinted onto the subduction earthquake cycle signal. With this interpretation, the Cascadia subduction margin appears to be well-coupled along its entire length, consistent with paleo-seismic records of large earthquake ruptures extending to its southern limit. At the Hikurangi to Alpine Fault transition in New Zealand, plate interactions switch from subduction to oblique translation as a consequence of changes in lithospheric structure of

  19. Parallel-Plate Electrostatic Dual Mass Oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Allen, James J.; Dyck, Christopher W.; Huber, Robert J.

    1999-07-22

    A surface-micromachined two-degree-of-freedom system that was driven by parallel-plate actuation at antiresonance was demonstrated. The system consisted of an absorbing mass connected by folded springs to a drive mass. The system demonstrated substantial motion amplification at antiresonance. The absorber mass amplitudes were 0.8-0.85 pm at atmospheric pressure while the drive mass amplitudes were below 0.1 pm. Larger absorber mass amplitudes were not possible because of spring softening in the drive mass springs. Simple theory of the dual-mass oscillator has indicated that the absorber mass may be insensitive to limited variations in strain and damping. This needs experimental verification. Resonant and antiresonant frequencies were measured and compared to the designed values. Resonant frequency measurements were difficult to compare to the design calculations because of time-varying spring softening terms that were caused by the drive configuration. Antiresonant frequency measurements were close to the design value of 5.1 kHz. The antiresonant frequency was not dependent on spring softening. The measured absorber mass displacement at antiresonance was compared to computer simulated results. The measured value was significantly greater, possibly due to neglecting fringe fields in the force expression used in the simulation.

  20. Seismic link at plate boundary

    Indian Academy of Sciences (India)

    transfer between two major faults, and parallel to the geothermal area extension. 1. Introduction. Plate boundaries are the zones where most earth dynamics are focussed. The complexity of tectonic boundaries draws attention to them as the largest earthquakes are felt in these areas and they elicit the natural hazard of ...

  1. Seismic link at plate boundary

    Indian Academy of Sciences (India)

    ... tested using the coherence of time series to determine the causality and related orientation. The resulting link orientations at the plate boundary conditions indicate that causal triggering seems to be localized along a major fault, as a stress transfer between two major faults, and parallel to the geothermal area extension.

  2. A high-resolution model for Eurasia-North America plate kinematics since 20 Ma

    Science.gov (United States)

    Merkouriev, S.; DeMets, C.

    2008-06-01

    We derive the first chronologically detailed model of Eurasia-North America plate motion since 20 Ma from ship and airplane surveys of the well-expressed magnetic lineations along this slowly spreading plate boundary, including previously unavailable dense Russian magnetic data from the southern Reykjanes Ridge and northern Mid-Atlantic ridge near the Charlie Gibbs fracture zone. From more than 7000 crossings of 21 magnetic anomalies from Anomaly 1n (0.78 Ma) to Anomaly 6n (19.7 Ma), we estimate best-fitting finite rotations and realistic uncertainties. Linear regressions of total opening distances versus their reversal ages at different locations along the plate boundary show that reversal boundaries are shifted systematically outwards from the spreading axis with respect to their idealized locations, with the outward shift ranging from more than 5 km between Iceland and the Charlie Gibbs fracture zone to ~2 km elsewhere. This outward displacement, which is a consequence of the finite zone of seafloor accretion, degrades estimates of the underlying plate motion and is thus removed for the ensuing kinematic analysis. The corrected plate motion rotations reveal surprising, previously unrecognized features in the relative motions of these two plates. Within the uncertainties, motion was steady from 20 to 8 Ma around a pole that was located ~600 km north of the present pole, with seafloor spreading rates that changed by no more than 5 per cent (1 mm yr-1) along the Reykjanes Ridge during this period. Seafloor spreading rates decreased abruptly by 20 +/- 2 per cent at 7.5-6.5 Ma, coinciding with rapid southward migration of the pole of rotation and a 5°-10° counter-clockwise change in the plate slip direction. Eurasia-North America plate motion since 6.7 Ma has remained remarkably steady, with an apparently stationary axis of rotation and upper limit of +/-2 per cent on any variations in the rate of angular rotation during this period. Based on the good agreement

  3. Considerable pancreatic tumor motion during breath-holding.

    Science.gov (United States)

    Lens, Eelco; van der Horst, Astrid; Versteijne, Eva; Bel, Arjan; van Tienhoven, Geertjan

    2016-11-01

    Breath-holding (BH) is often used to reduce abdominal organ motion during radiotherapy. However, for inhale BH, abdominal tumor motion during BH has not yet been investigated. The aim of this study was to quantify tumor motion during inhale BH and tumor position variations between consecutive inhale BHs in pancreatic cancer patients. Twelve patients with intratumoral fiducials were included and asked to perform three consecutive 30-second inhale BHs on each of three measurement days. During BH, lateral fluoroscopic movies were obtained and a two-dimensional (2D) image correlation algorithm was used to track the fiducials and the diaphragm, yielding the tumor and diaphragm motion during each BH. The tumor position variation between consecutive BHs was obtained from the difference in initial tumor position between consecutive BHs on a single measurement day. We observed tumor motion during BH with a mean absolute maximum displacement over all BHs of 4.2 mm (range 1.0-11.0 mm) in inferior-superior (IS) direction and 2.7 mm (range 0.5-8.0 mm) in anterior-posterior (AP) direction. We found only a moderate correlation between tumor and diaphragm motion in the IS direction (Pearson's correlation coefficient |r|>0.6 in 45 of 76 BHs). The mean tumor position variation between consecutive BHs was 0.2 [standard deviation (SD) 1.7] mm in the inferior direction and 0.5 (SD 0.8) mm in the anterior direction. We observed substantial pancreatic tumor motion during BH as well as considerable position variation between consecutive BHs on a single day. We recommend further quantifying these uncertainties before introducing breath-hold during radiation treatment of pancreatic cancer patients. Also, the diaphragm cannot be used as a surrogate for pancreatic tumor motion.

  4. Observations in the Past of Solar System Bodies with MAO NANU Plate Archives

    Science.gov (United States)

    Sergeeva, T. P.; Golovnya, V. V.; Yizhakevych, E. M.; Shatokhina, S. V.; Sergeev, A. V.

    2006-04-01

    The plate archives of the Main Astronomical Observatory of the National Academy of Sciences of Ukraine contain more than 100,000 images of minor planets with magnitude up to 16.7m. About 10% of the minor planets, found on our archival plates, were discovered many years after taking the plates. So we can rediscover them by so called "observation in the past" and obtain their positions for improvement of the dynamical models of their motions. Other Solar System bodies for which we try to get "observation in the past" are the external planets satellites. The criteria for chosen objects, the search methods, identification and determination of positions are discussed. The first results of the asteroids and the external planet satellites search in MAO plate archives are presented.

  5. Nonlinear Dynamic Response of Functionally Graded Rectangular Plates under Different Internal Resonances

    Directory of Open Access Journals (Sweden)

    Y. X. Hao

    2010-01-01

    Full Text Available The nonlinear dynamic response of functionally graded rectangular plates under combined transverse and in-plane excitations is investigated under the conditions of 1 : 1, 1 : 2 and 1 : 3 internal resonance. The material properties are assumed to be temperature-dependent and vary along the thickness direction. The thermal effect due to one-dimensional temperature gradient is included in the analysis. The governing equations of motion for FGM rectangular plates are derived by using Reddy's third-order plate theory and Hamilton's principle. Galerkin's approach is utilized to reduce the governing differential equations to a two-degree-of-freedom nonlinear system including quadratic and cubic nonlinear terms, which are then solved numerically by using 4th-order Runge-Kutta algorithm. The effects of in-plane excitations on the internal resonance relationship and nonlinear dynamic response of FGM plates are studied.

  6. Exact vibration analysis of variable thickness thick annular isotropic and FGM plates

    Science.gov (United States)

    Efraim, E.; Eisenberger, M.

    2007-02-01

    Annular plates are used in many engineering structures. In many cases variable thickness is used in order to save weight and improve structural characteristics. In recent years functionally graded materials (FGM) are used in many engineering applications. A FGM plate is an inhomogeneous composite made of two constituents (usually ceramic and metal), with both the composition and the material properties varying smoothly through the thickness of the plate. An optimal distribution of material properties may be obtained. The plate vibrations will have a strong bending-stretching coupling effect. The equations of motion including the effect of shear deformations using the first-order shear deformation theory are derived and solved exactly for various combinations of boundary conditions. The solution is obtained by using the exact element method. Exact vibration frequencies and modes are given for several examples for the first time.

  7. Treatment of symptomatic non-unions of the base of the ulnar styloid with plate osteosynthesis.

    Science.gov (United States)

    Nunez, F A; Luo, T D; Nunez, F A

    2017-05-01

    The purpose of this prospective case series was to assess the efficacy of plate osteosynthesis using a low profile distal ulna plate for the management of persistently symptomatic non-unions of the base of the ulnar styloid. Six consecutive patients underwent resection of the non-union and plate osteosynthesis with a 2.0 mm distal ulna hook plate. Post-operative measurements of mean pain scores, QuickDASH scores, grip strength, and range of motion parameters showed significant improvements compared with the pre-operative values. No complications were reported at a mean follow-up of 25 months. The present study presents an alternative method for treating symptomatic ulnar styloid non-unions that provides stable fixation with low risk of implant removal. Therapeutic IV.

  8. Active control of sound transmission/radiation from elastic plates by vibration inputs. II - Experiments

    Science.gov (United States)

    Metcalf, V. L.; Fuller, C. R.; Silcox, R. J.; Brown, D. E.

    1992-01-01

    Actively controlled harmonic force inputs were applied experimentally to reduce the sound transmitted through an elastic circular plate. The control implementation used a time domain least mean square adaptive algorithm with two error sensors. The control forces were applied directly to the plate by point force vibration inputs, while the error information and performance were measured in the radiated acoustic field by microphones. Test cases were also performed in which the error sensors were accelerometers mounted on the plate. When accelerometers were used as error sensors, the controller performance was degraded; leading to the conclusion that minimizing plate motion does not necessarily lead to an associated decrease in radiated sound levels. In contrast, the results show excellent attenuation of the transmitted sound field when microphone error sensors were used. This result was consistent over a range of frequencies. In addition, the experimental results are compared to previously derived analytical results and the effect of using a point or global minimization scheme is discussed.

  9. The concurrent emergence and causes of double volcanic hotspot tracks on the Pacific plate

    DEFF Research Database (Denmark)

    Jones, David T; Davies, D. R.; Campbell, I. H.

    2017-01-01

    Mantle plumes are buoyant upwellings of hot rock that transport heat from Earth's core to its surface, generating anomalous regions of volcanism that are not directly associated with plate tectonic processes. The best-studied example is the Hawaiian-Emperor chain, but the emergence of two sub......-parallel volcanic tracks along this chain, Loa and Kea, and the systematic geochemical differences between them have remained unexplained. Here we argue that the emergence of these tracks coincides with the appearance of other double volcanic tracks on the Pacific plate and a recent azimuthal change in the motion...... of the plate. We propose a three-part model that explains the evolution of Hawaiian double-track volcanism: first, mantle flow beneath the rapidly moving Pacific plate strongly tilts the Hawaiian plume and leads to lateral separation between high- and low-pressure melt source regions; second, the recent...

  10. Full-motion video analysis for improved gender classification

    Science.gov (United States)

    Flora, Jeffrey B.; Lochtefeld, Darrell F.; Iftekharuddin, Khan M.

    2014-06-01

    The ability of computer systems to perform gender classification using the dynamic motion of the human subject has important applications in medicine, human factors, and human-computer interface systems. Previous works in motion analysis have used data from sensors (including gyroscopes, accelerometers, and force plates), radar signatures, and video. However, full-motion video, motion capture, range data provides a higher resolution time and spatial dataset for the analysis of dynamic motion. Works using motion capture data have been limited by small datasets in a controlled environment. In this paper, we explore machine learning techniques to a new dataset that has a larger number of subjects. Additionally, these subjects move unrestricted through a capture volume, representing a more realistic, less controlled environment. We conclude that existing linear classification methods are insufficient for the gender classification for larger dataset captured in relatively uncontrolled environment. A method based on a nonlinear support vector machine classifier is proposed to obtain gender classification for the larger dataset. In experimental testing with a dataset consisting of 98 trials (49 subjects, 2 trials per subject), classification rates using leave-one-out cross-validation are improved from 73% using linear discriminant analysis to 88% using the nonlinear support vector machine classifier.

  11. Operational test of bonded magnetocaloric plates

    DEFF Research Database (Denmark)

    Bahl, Christian; Navickaité, Kristina; Neves Bez, Henrique

    2017-01-01

    Bonded plates made by hot pressing La0.85Ce0.15Fe11.25Mn0.25Si1.5Hy particles and resin have been tested as active magnetic regenerators in a small scale magnetocaloric device. Firstly the plates were carefully characterised magnetically and thermally. The plates were prepared with 5 wt% resin......, and from density measurements it was found that the volume ratio of the magnetocaloric material in the plates was 0.53, due to the resin and porosity. The best operating conditions for the plate regenerator were determined at which a temperature span of 6.4 K was measured along the plates....

  12. Range of motion after thoracolumbar corpectomy

    DEFF Research Database (Denmark)

    Gehrchen, Martin; Hegde, Sajan K; Moldavsky, Mark

    2017-01-01

    STUDY DESIGN: An in vitro biomechanical study. OBJECTIVES: To compare the biomechanical stability of traditional and low-profile thorocolumbar anterior instrumentation after a corpectomy with cross-connectors. Dual-rod anterior thoracolumbar lateral plates (ATLP) have been used clinically...... to stabilize the thorocolumbar spine. METHODS: The stability of a low-profile dual-rod system (LP DRS) and a traditional dual-rod system (DRS) was compared using a calf spine model. Two groups of seven specimens were tested intact and then in the following order: (1) ATLP with two cross-connectors and spacer......; (2) ATLP with one cross-connector and spacer; (3) ATLP with spacer. Data were normalized to intact (100 %) and statistical analysis was used to determine between-group significances. RESULTS: Both constructs reduced motion compared to intact in flexion-extension and lateral bending. Axial rotation...

  13. Biomechanical Performance of Lateral Versus Dual Locking Plates for Calcaneal Fractures.

    Science.gov (United States)

    Maxwell, Abby B; Owen, John R; Gilbert, Todd M; Romash, Michael M; Wayne, Jennifer S; Adelaar, Robert S

    2015-01-01

    Given the high rates of wound complications with a standard lateral extensile incision, small dual incision techniques might result in less soft tissue destruction. The goal of the present study was to compare the biomechanical performance between a single locking plate and a dual locking plating system for an intra-articular calcaneal fracture model. A Sanders IIB type joint depression calcaneal fracture was created in 10 paired, fresh-frozen, cadaveric calcanei (age 47 ± 12, range 35 to 78 years). The calcanei of each pair were randomly assigned for fixation using either a lateral locking reconstruction plate or lateral and medial locking reconstruction plates. The specimens were axially loaded in cyclic fashion for 1000 cycles, followed by load to failure. The relative fragment movement was monitored optically in both the sagittal and the coronal planes. The amount of overall construct displacement increased with cycling, although no difference was found between the plating techniques. For fragment movement during cycling, the lateral joint fragment migrated anteroinferiorly along the fracture line relative to the tuberosity fragment for dual plated specimens by a small, but statistically significant, amount. This same translation was smaller for lateral plated specimens but was not found to be significant. During load to failure testing, no statistically significant differences were found for construct stiffness. A tendency was seen toward more interfragmentary motion in the sagittal plane (lateral joint fragment movement relative to the fracture line), with less movement overall in the coronal plane (anterior fragment translation and twist) for dual plating, although the difference from the lateral plate was not statistically significant. The present study demonstrated that for this calcaneal fracture model, the dual plating technique experienced a small amount of fragment translation during cycling that was significantly different statistically from that

  14. Ground motion effects

    International Nuclear Information System (INIS)

    Blume, J.A.

    1969-01-01

    Ground motion caused by natural earthquakes or by nuclear explosion causes buildings and other structures to respond in such manner as possibly to have high unit stresses and to be subject to damage or-in some cases-collapse. Even minor damage may constitute a hazard to persons within or adjacent to buildings. The risk of damage may well be the governing restraint on the uses of nuclear energy for peaceful purposes. Theory is advanced regarding structural-dynamic response but real buildings and structures are complex, highly variable, and often difficult to model realistically. This paper discusses the state of knowledge, the art of damage prediction and safety precautions, and shows ground motion effects from explosions of underground nuclear devices in the continental United States including events Salmon, Gasbuggy, Boxcar, Faultless and Benham. (author)

  15. Effect of splitter plate on unsteady flows around a body of revolution at incidence

    Science.gov (United States)

    Degani, David

    1991-01-01

    Numerical solutions of the thin-layer approximation of the 3D Navier-Stokes equations are presented for flows around an ogive-cylinder body with and without a splitter plate. It is suggested that the presence of the splitter plate prevents the interaction between flows on either side of the symmetry plane. It is concluded that, as a result of the enforced symmetry, the antisymmetric mode of the convective instability near the apex of the body cannot be excited and, therefore, the vortices remain symmetric, staying low and parallel to the upper body surface. The antisymmetric mode of the absolute instability mechanism cannot be initiated, which suppresses the alternate shedding of vortices from the cylindrical portion of the body. High-frequency fluctuations of the shear layer are found to remain virtually unaffected by the presence of the splitter plate.

  16. A prospective randomized study of operative treatment for noncomminuted humeral shaft fractures: conventional open plating versus minimal invasive plate osteosynthesis.

    Science.gov (United States)

    Kim, Ji Wan; Oh, Chang-Wug; Byun, Young-Soo; Kim, Jung Jae; Park, Ki Chul

    2015-04-01

    To compare the clinical and radiologic results of conventional open plating (COP) and minimally invasive plate osteosynthesis (MIPO) in the treatment of noncomminuted humeral shaft fractures. Randomized prospective study. Five level 1 trauma centers. Sixty-eight consecutive patients were randomized into 2 study groups: those treated by COP (COP group; n = 32) and those treated by MIPO (MIPO group; n = 36). Simple humeral shaft fractures (AO/OTA classification types A and B) were reduced by open reduction or closed reduction and fixed with a narrow 4.5/5.0 locking compression plate, metaphyseal locking compression plate, or proximal humeral internal locking system plate to the anterior lateral aspect of the humerus. Fracture healing time, operative time, radiation exposure time, and intraoperative nerve injury. To assess shoulder and elbow function, we used the University of California, Los Angeles (UCLA) scoring system and the Mayo elbow performance index, including the range of motion and pain. Radiographic measurements included fracture alignment, delayed union, and nonunion. Thirty-one fractures (97%) healed in the COP group within 16 weeks, whereas 36 fractures (100%) were healed in the MIPO group by 15 weeks. No significant difference was observed in the operative time or complication rates. In both groups, all fractures achieved union without malunion and with excellent functional outcomes by definition of the Mayo elbow performance index and UCLA scoring system. This study confirmed a high overall rate of union and excellent functional outcomes in both MIPO and COP groups. MIPO is equivalent to COP as a safe and effective method for simple types of humeral shaft fractures when surgery is indicated, and the surgeon is experienced in the technique. Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

  17. Motion of the esophagus due to cardiac motion.

    Directory of Open Access Journals (Sweden)

    Jacob Palmer

    Full Text Available When imaging studies (e.g. CT are used to quantify morphological changes in an anatomical structure, it is necessary to understand the extent and source of motion which can give imaging artifacts (e.g. blurring or local distortion. The objective of this study was to assess the magnitude of esophageal motion due to cardiac motion. We used retrospective electrocardiogram-gated contrast-enhanced computed tomography angiography images for this study. The anatomic region from the carina to the bottom of the heart was taken at deep-inspiration breath hold with the patients' arms raised above their shoulders, in a position similar to that used for radiation therapy. The esophagus was delineated on the diastolic phase of cardiac motion, and deformable registration was used to sequentially deform the images in nearest-neighbor phases among the 10 cardiac phases, starting from the diastolic phase. Using the 10 deformation fields generated from the deformable registration, the magnitude of the extreme displacements was then calculated for each voxel, and the mean and maximum displacement was calculated for each computed tomography slice for each patient. The average maximum esophageal displacement due to cardiac motion for all patients was 5.8 mm (standard deviation: 1.6 mm, maximum: 10.0 mm in the transverse direction. For 21 of 26 patients, the largest esophageal motion was found in the inferior region of the heart; for the other patients, esophageal motion was approximately independent of superior-inferior position. The esophagus motion was larger at cardiac phases where the electrocardiogram R-wave occurs. In conclusion, the magnitude of esophageal motion near the heart due to cardiac motion is similar to that due to other sources of motion, including respiratory motion and intra-fraction motion. A larger cardiac motion will result into larger esophagus motion in a cardiac cycle.

  18. SM-ROM-GL (Strong Motion Romania Ground Level Database

    Directory of Open Access Journals (Sweden)

    Ioan Sorin BORCIA

    2015-07-01

    Full Text Available The SM-ROM-GL database includes data obtained by the processing of records performed at ground level by the Romanian seismic networks, namely INCERC, NIEP, NCSRR and ISPH-GEOTEC, during recent seismic events with moment magnitude Mw ≥ 5 and epicenters located in Romania. All the available seismic records were re-processed using the same basic software and the same procedures and options (filtering and baseline correction, in order to obtain a consistent dataset. The database stores computed parameters of seismic motions, i.e. peak values: PGA, PGV, PGD, effective peak values: EPA, EPV, EPD, control periods, spectral values of absolute acceleration, relative velocity and relative displacement, as well as of instrumental intensity (as defined bz Sandi and Borcia in 2011. The fields in the database include: coding of seismic events, stations and records, a number of associated fields (seismic event source parameters, geographical coordinates of seismic stations, links to the corresponding ground motion records, charts of the response spectra of absolute acceleration, relative velocity, relative displacement and instrumental intensity, as well as some other representative parameters of seismic motions. The conception of the SM-ROM-GL database allows for an easy maintenance; such that elementary knowledge of Microsoft Access 2000 is sufficient for its operation.

  19. Force and motion

    CERN Document Server

    Robertson, William C

    2002-01-01

    Intimidated by inertia? Frightened by forces? Mystified by Newton s law of motion? You re not alone and help is at hand. The stop Faking It! Series is perfect for science teachers, home-schoolers, parents wanting to help with homework all of you who need a jargon-free way to learn the background for teaching middle school physical science with confidence. With Bill Roberton as your friendly, able but somewhat irreverent guide, you will discover you CAN come to grips with the basics of force and motion. Combining easy-to-understand explanations with activities using commonly found equipment, this book will lead you through Newton s laws to the physics of space travel. The book is as entertaining as it is informative. Best of all, the author understands the needs of adults who want concrete examples, hands-on activities, clear language, diagrams and yes, a certain amount of empathy. Ideas For Use Newton's laws, and all of the other motion principles presented in this book, do a good job of helping us to underst...

  20. Henry More and the development of absolute time.

    Science.gov (United States)

    Thomas, Emily

    2015-12-01

    This paper explores the nature, development and influence of the first English account of absolute time, put forward in the mid-seventeenth century by the 'Cambridge Platonist' Henry More. Against claims in the literature that More does not have an account of time, this paper sets out More's evolving account and shows that it reveals the lasting influence of Plotinus. Further, this paper argues that More developed his views on time in response to his adoption of Descartes' vortex cosmology and cosmogony, providing new evidence of More's wider project to absorb Cartesian natural philosophy into his Platonic metaphysics. Finally, this paper argues that More should be added to the list of sources that later English thinkers - including Newton and Samuel Clarke - drew on in constructing their absolute accounts of time. Copyright © 2015 Elsevier Ltd. All rights reserved.