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Sample records for meridional return flow

  1. DETECTION OF EQUATORWARD MERIDIONAL FLOW AND EVIDENCE OF DOUBLE-CELL MERIDIONAL CIRCULATION INSIDE THE SUN

    International Nuclear Information System (INIS)

    Zhao Junwei; Bogart, R. S.; Kosovichev, A. G.; Hartlep, Thomas; Duvall, T. L. Jr.

    2013-01-01

    Meridional flow in the solar interior plays an important role in redistributing angular momentum and transporting magnetic flux inside the Sun. Although it has long been recognized that the meridional flow is predominantly poleward at the Sun's surface and in its shallow interior, the location of the equatorward return flow and the meridional flow profile in the deeper interior remain unclear. Using the first 2 yr of continuous helioseismology observations from the Solar Dynamics Observatory/Helioseismic Magnetic Imager, we analyze travel times of acoustic waves that propagate through different depths of the solar interior carrying information about the solar interior dynamics. After removing a systematic center-to-limb effect in the helioseismic measurements and performing inversions for flow speed, we find that the poleward meridional flow of a speed of 15 m s –1 extends in depth from the photosphere to about 0.91 R ☉ . An equatorward flow of a speed of 10 m s –1 is found between 0.82 and 0.91 R ☉ in the middle of the convection zone. Our analysis also shows evidence of that the meridional flow turns poleward again below 0.82 R ☉ , indicating an existence of a second meridional circulation cell below the shallower one. This double-cell meridional circulation profile with an equatorward flow shallower than previously thought suggests a rethinking of how magnetic field is generated and redistributed inside the Sun

  2. DETECTION OF EQUATORWARD MERIDIONAL FLOW AND EVIDENCE OF DOUBLE-CELL MERIDIONAL CIRCULATION INSIDE THE SUN

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Junwei; Bogart, R. S.; Kosovichev, A. G.; Hartlep, Thomas [W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305-4085 (United States); Duvall, T. L. Jr. [Solar Physics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2013-09-10

    Meridional flow in the solar interior plays an important role in redistributing angular momentum and transporting magnetic flux inside the Sun. Although it has long been recognized that the meridional flow is predominantly poleward at the Sun's surface and in its shallow interior, the location of the equatorward return flow and the meridional flow profile in the deeper interior remain unclear. Using the first 2 yr of continuous helioseismology observations from the Solar Dynamics Observatory/Helioseismic Magnetic Imager, we analyze travel times of acoustic waves that propagate through different depths of the solar interior carrying information about the solar interior dynamics. After removing a systematic center-to-limb effect in the helioseismic measurements and performing inversions for flow speed, we find that the poleward meridional flow of a speed of 15 m s{sup -1} extends in depth from the photosphere to about 0.91 R{sub Sun }. An equatorward flow of a speed of 10 m s{sup -1} is found between 0.82 and 0.91 R{sub Sun} in the middle of the convection zone. Our analysis also shows evidence of that the meridional flow turns poleward again below 0.82 R{sub Sun }, indicating an existence of a second meridional circulation cell below the shallower one. This double-cell meridional circulation profile with an equatorward flow shallower than previously thought suggests a rethinking of how magnetic field is generated and redistributed inside the Sun.

  3. Inferences of the deep solar meridional flow

    Science.gov (United States)

    Böning, Vincent G. A.

    2017-10-01

    from earlier studies leads to errors in the inverted flows being underestimated by a factor of about two to four. The inverted meridional flow above about 0.85 solar radii confirms the earlier results from ray theory regarding the general pattern of the flow, especially regarding a shallow return flow at about 0.9 solar radii, with some differences in the magnitude of the flow. Below about 0.85 solar radii, the inversion result depends on the thresholds used in the singular value decomposition. One result is again similar to the original regarding its general single-cell shape. Other results show a multi-cell structure in the southern hemisphere with two or three cells stacked radially. However, both the single-cell and the multi-cell flow profiles are consistent with the measured travel times within the measurement errors. To reach an unambiguous conclusion on the meridional flow below about 0.85 solar radii, the errors in the measured travel times have to be decreased considerably in future studies. For now, I conclude that the existing controversy of recent measurements of the deep meridional flow is relaxed by properly taking the associated errors into account.

  4. Solar-cycle variation of zonal and meridional flow

    International Nuclear Information System (INIS)

    Komm, R; Howe, R; Hill, F; Hernandez, I Gonzalez; Haber, D

    2011-01-01

    We study the variation with the solar cycle of the zonal and meridional flows in the near-surface layers of the solar convection zone. We have analyzed MDI Dynamics-Program data with ring-diagram analysis covering the rising phase of cycle 23, while the analyzed GONG high-resolution data cover the maximum and declining phase of cycle 23. For the zonal flow, the migration with latitude of the flow pattern is apparent in the deeper layers, while for the meridional flow, a migration with latitude is apparent only in the layers close to the surface. The faster-than-average bands of the zonal flow associated with the new cycle are clearly visible. Similarly, a pattern related to the new cycle appears in the residual meridional flow. We also study the flow differences between the hemispheres during the course of the solar cycle. The difference pattern of the meridional flow is slanted in latitude straddling the faster-than-average band of the torsional oscillation pattern in the zonal flow. The difference pattern of the zonal flow, on the other hand, resembles the cycle variation of the meridional flow. In addition, the meridional flow during the minimum of cycle 23/24 appears to be slightly stronger than during the previous minimum of cycle 22/23.

  5. Meridional Flow Observations: Implications for the current Flux Transport Models

    International Nuclear Information System (INIS)

    Gonzalez Hernandez, Irene; Komm, Rudolf; Kholikov, Shukur; Howe, Rachel; Hill, Frank

    2011-01-01

    Meridional circulation has become a key element in the solar dynamo flux transport models. Available helioseismic observations from several instruments, Taiwan Oscillation Network (TON), Global Oscillation Network Group (GONG) and Michelson Doppler Imager (MDI), have made possible a continuous monitoring of the solar meridional flow in the subphotospheric layers for the last solar cycle, including the recent extended minimum. Here we review some of the meridional circulation observations using local helioseismology techniques and relate them to magnetic flux transport models.

  6. Is a deep one-cell meridional circulation essential for the flux transport solar dynamo?

    International Nuclear Information System (INIS)

    Hazra, Gopal; Karak, Bidya Binay; Choudhuri, Arnab Rai

    2014-01-01

    The solar activity cycle is successfully modeled by the flux transport dynamo, in which the meridional circulation of the Sun plays an important role. Most of the kinematic dynamo simulations assume a one-cell structure of the meridional circulation within the convection zone, with the equatorward return flow at its bottom. In view of the recent claims that the return flow occurs at a much shallower depth, we explore whether a meridional circulation with such a shallow return flow can still retain the attractive features of the flux transport dynamo (such as a proper butterfly diagram, the proper phase relation between the toroidal and poloidal fields). We consider additional cells of the meridional circulation below the shallow return flow—both the case of multiple cells radially stacked above one another and the case of more complicated cell patterns. As long as there is an equatorward flow in low latitudes at the bottom of the convection zone, we find that the solar behavior is approximately reproduced. However, if there is either no flow or a poleward flow at the bottom of the convection zone, then we cannot reproduce solar behavior. On making the turbulent diffusivity low, we still find periodic behavior, although the period of the cycle becomes unrealistically large. In addition, with a low diffusivity, we do not get the observed correlation between the polar field at the sunspot minimum and the strength of the next cycle, which is reproduced when diffusivity is high. On introducing radially downward pumping, we get a more reasonable period and more solar-like behavior even with low diffusivity.

  7. Is a deep one-cell meridional circulation essential for the flux transport solar dynamo?

    Energy Technology Data Exchange (ETDEWEB)

    Hazra, Gopal; Karak, Bidya Binay; Choudhuri, Arnab Rai, E-mail: ghazra@physics.iisc.ernet.in [Department of Physics, Indian Institute of Science, Bangalore 560012 (India)

    2014-02-20

    The solar activity cycle is successfully modeled by the flux transport dynamo, in which the meridional circulation of the Sun plays an important role. Most of the kinematic dynamo simulations assume a one-cell structure of the meridional circulation within the convection zone, with the equatorward return flow at its bottom. In view of the recent claims that the return flow occurs at a much shallower depth, we explore whether a meridional circulation with such a shallow return flow can still retain the attractive features of the flux transport dynamo (such as a proper butterfly diagram, the proper phase relation between the toroidal and poloidal fields). We consider additional cells of the meridional circulation below the shallow return flow—both the case of multiple cells radially stacked above one another and the case of more complicated cell patterns. As long as there is an equatorward flow in low latitudes at the bottom of the convection zone, we find that the solar behavior is approximately reproduced. However, if there is either no flow or a poleward flow at the bottom of the convection zone, then we cannot reproduce solar behavior. On making the turbulent diffusivity low, we still find periodic behavior, although the period of the cycle becomes unrealistically large. In addition, with a low diffusivity, we do not get the observed correlation between the polar field at the sunspot minimum and the strength of the next cycle, which is reproduced when diffusivity is high. On introducing radially downward pumping, we get a more reasonable period and more solar-like behavior even with low diffusivity.

  8. Effects of the Observed Meridional Flow Variations since 1996 on the Sun's Polar Fields

    Science.gov (United States)

    Hathaway, David H.; Upton, Lisa

    2013-01-01

    The cause of the low and extended minimum in solar activity between Sunspot Cycles 23 and 24 was the small size of Sunspot Cycle 24 itself - small cycles start late and leave behind low minima. Cycle 24 is small because the polar fields produced during Cycle 23 were substantially weaker than those produced during the previous cycles and those (weak) polar fields are the seeds for the activity of the following cycle. The polar fields are produced by the latitudinal transport of magnetic flux that emerged in low-latitude active regions. The polar fields thus depend upon the details of both the flux emergence and the flux transport. We have measured the flux transport flows (differential rotation, meridional flow, and supergranules) since 1996 and find systematic and substantial variation in the meridional flow alone. Here we present experiments using a Surface Flux Transport Model in which magnetic field data from SOHO/MDI and SDO/HMI are assimilated into the model only at latitudes between 45-degrees north and south of the equator (this assures that the details of the active region flux emergence are well represented). This flux is then transported in both longitude and latitude by the observed flows. In one experiment the meridional flow is given by the time averaged (and north-south symmetric) meridional flow profile. In the second experiment the time-varying and north-south asymmetric meridional flow is used. Differences between the observed polar fields and those produced in these two experiments allow us to ascertain the effects of these meridional flow variations on the Sun s polar fields.

  9. Solar-cycle Variations of Meridional Flows in the Solar Convection Zone Using Helioseismic Methods

    Science.gov (United States)

    Lin, Chia-Hsien; Chou, Dean-Yi

    2018-06-01

    The solar meridional flow is an axisymmetric flow in solar meridional planes, extending through the convection zone. Here we study its solar-cycle variations in the convection zone using SOHO/MDI helioseismic data from 1996 to 2010, including two solar minima and one maximum. The travel-time difference between northward and southward acoustic waves is related to the meridional flow along the wave path. Applying the ray approximation and the SOLA inversion method to the travel-time difference measured in a previous study, we obtain the meridional flow distributions in 0.67 ≤ r ≤ 0.96R ⊙ at the minimum and maximum. At the minimum, the flow has a three-layer structure: poleward in the upper convection zone, equatorward in the middle convection zone, and poleward again in the lower convection zone. The flow speed is close to zero within the error bar near the base of the convection zone. The flow distribution changes significantly from the minimum to the maximum. The change above 0.9R ⊙ shows two phenomena: first, the poleward flow speed is reduced at the maximum; second, an additional convergent flow centered at the active latitudes is generated at the maximum. These two phenomena are consistent with the surface meridional flow reported in previous studies. The change in flow extends all the way down to the base of the convection zone, and the pattern of the change below 0.9R ⊙ is more complicated. However, it is clear that the active latitudes play a role in the flow change: the changes in flow speed below and above the active latitudes have opposite signs. This suggests that magnetic fields could be responsible for the flow change.

  10. Meridional flow in the solar convection zone. I. Measurements from gong data

    Energy Technology Data Exchange (ETDEWEB)

    Kholikov, S. [National Solar Observatories, Tucson, AZ 85719 (United States); Serebryanskiy, A. [Ulugh Beg Astronomical Institute, Uzbek Academy of Science, Tashkent 100052 (Uzbekistan); Jackiewicz, J., E-mail: kholikov@noao.edu [Department of Astronomy, New Mexico State University, Las Cruces, NM 88003 (United States)

    2014-04-01

    Large-scale plasma flows in the Sun's convection zone likely play a major role in solar dynamics on decadal timescales. In particular, quantifying meridional motions is a critical ingredient for understanding the solar cycle and the transport of magnetic flux. Because the signal of such features can be quite small in deep solar layers and be buried in systematics or noise, the true meridional velocity profile has remained elusive. We perform time-distance helioseismology measurements on several years worth of Global Oscillation Network Group Doppler data. A spherical harmonic decomposition technique is applied to a subset of acoustic modes to measure travel-time differences to try to obtain signatures of meridional flows throughout the solar convection zone. Center-to-limb systematics are taken into account in an intuitive yet ad hoc manner. Travel-time differences near the surface that are consistent with a poleward flow in each hemisphere and are similar to previous work are measured. Additionally, measurements in deep layers near the base of the convection zone suggest a possible equatorward flow, as well as partial evidence of a sign change in the travel-time differences at mid-convection zone depths. This analysis on an independent data set using different measurement techniques strengthens recent conclusions that the convection zone may have multiple 'cells' of meridional flow. The results may challenge the common understanding of one large conveyor belt operating in the solar convection zone. Further work with helioseismic inversions and a careful study of systematic effects are needed before firm conclusions of these large-scale flow structures can be made.

  11. SOLAR WAVE-FIELD SIMULATION FOR TESTING PROSPECTS OF HELIOSEISMIC MEASUREMENTS OF DEEP MERIDIONAL FLOWS

    International Nuclear Information System (INIS)

    Hartlep, T.; Zhao, J.; Kosovichev, A. G.; Mansour, N. N.

    2013-01-01

    The meridional flow in the Sun is an axisymmetric flow that is generally directed poleward at the surface, and is presumed to be of fundamental importance in the generation and transport of magnetic fields. Its true shape and strength, however, are debated. We present a numerical simulation of helioseismic wave propagation in the whole solar interior in the presence of a prescribed, stationary, single-cell, deep meridional circulation serving as synthetic data for helioseismic measurement techniques. A deep-focusing time-distance helioseismology technique is applied to the synthetic data, showing that it can in fact be used to measure the effects of the meridional flow very deep in the solar convection zone. It is shown that the ray approximation that is commonly used for interpretation of helioseismology measurements remains a reasonable approximation even for very long distances between 12° and 42° corresponding to depths between 52 and 195 Mm. From the measurement noise, we extrapolate that time-resolved observations on the order of a full solar cycle may be needed to probe the flow all the way to the base of the convection zone.

  12. Meridional-Flow Measurements from 15 Years of GONG Spherical-Harmonic Time Series

    International Nuclear Information System (INIS)

    Kholikov, S; Hernandez, I Gonzalez; Hill, F; Leibacher, J

    2011-01-01

    We present results of meridional-flow measurements for 1995-2009, using travel-time differences from velocity images reconstructed using GONG spherical harmonic (SH) coefficients after applying phase-velocity and low-m filters. This filtering technique increases the signal-to-noise ratio and thus extends travel-time measurements to relatively high latitudes and deep into the convection zone. Preliminary analyses shows a strong one-year periodicity presumably due to solar pole misalignment and B 0 -angle artifacts, which makes it difficult to see underlying temporal variations. Removing a simple one-year-period sine wave fit reveals long-term temporal variations of the flow on top of this yearly periodicity. High-latitude measurements are affected more stronger by foreshortening and B 0 -angle artifacts. We analyze different B 0 -angle intervals separately, so in each hemisphere better high-latitude visibility comes six months apart. This approach suggests why at high latitudes travel-time measurements of meridional flow shows a tendency to change sign instead of continuing towards the poles.

  13. Storm-time meridional flows: a comparison of CINDI observations and model results

    Directory of Open Access Journals (Sweden)

    M. Hairston

    2014-06-01

    Full Text Available During a large geomagnetic storm, the electric field from the polar ionosphere can expand far enough to affect the mid-latitude and equatorial electric fields. These changes in the equatorial zonal electric field, called the penetration field, will cause changes in the meridional ion flows that can be observed by radars and spacecraft. In general this E × B ion flow near the equator caused by the penetration field during undershielding conditions will be upward on the dayside and downward on the nightside of the Earth. Previous analysis of the equatorial meridional flows observed by CINDI instrument on the C/NOFS spacecraft during the 26 September 2011 storm showed that all of the response flows on the dayside were excess downward flows instead of the expected upward flows. These observed storm-time responses are compared to a prediction from a physics-based coupled model of thermosphere–ionosphere–inner-magnetosphere in an effort to explain these observations. The model results suggest that the equatorial downward flow could be attributed to a combined effect of the overshielding and disturbance dynamo processes. However, some discrepancy between the model and observation indicates a need for improving our understanding of how sensitive the equatorial electric field is to various model input parameters that describe the magnetosphere–ionosphere coupling processes.

  14. THEORY OF SOLAR MERIDIONAL CIRCULATION AT HIGH LATITUDES

    International Nuclear Information System (INIS)

    Dikpati, Mausumi; Gilman, Peter A.

    2012-01-01

    We build a hydrodynamic model for computing and understanding the Sun's large-scale high-latitude flows, including Coriolis forces, turbulent diffusion of momentum, and gyroscopic pumping. Side boundaries of the spherical 'polar cap', our computational domain, are located at latitudes ≥ 60°. Implementing observed low-latitude flows as side boundary conditions, we solve the flow equations for a Cartesian analog of the polar cap. The key parameter that determines whether there are nodes in the high-latitude meridional flow is ε = 2ΩnπH 2 /ν, where Ω is the interior rotation rate, n is the radial wavenumber of the meridional flow, H is the depth of the convection zone, and ν is the turbulent viscosity. The smaller the ε (larger turbulent viscosity), the fewer the number of nodes in high latitudes. For all latitudes within the polar cap, we find three nodes for ν = 10 12 cm 2 s –1 , two for 10 13 , and one or none for 10 15 or higher. For ν near 10 14 our model exhibits 'node merging': as the meridional flow speed is increased, two nodes cancel each other, leaving no nodes. On the other hand, for fixed flow speed at the boundary, as ν is increased the poleward-most node migrates to the pole and disappears, ultimately for high enough ν leaving no nodes. These results suggest that primary poleward surface meridional flow can extend from 60° to the pole either by node merging or by node migration and disappearance.

  15. SYSTEMATIC CENTER-TO-LIMB VARIATION IN MEASURED HELIOSEISMIC TRAVEL TIMES AND ITS EFFECT ON INFERENCES OF SOLAR INTERIOR MERIDIONAL FLOWS

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Junwei; Nagashima, Kaori; Bogart, R. S.; Kosovichev, A. G. [W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305-4085 (United States); Duvall, T. L. Jr. [Solar Physics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2012-04-10

    We report on a systematic center-to-limb variation in measured helioseismic travel times, which must be taken into account for an accurate determination of solar interior meridional flows. The systematic variation, found in time-distance helioseismology analysis using SDO/HMI and SDO/AIA observations, is different in both travel-time magnitude and variation trend for different observables. It is not clear what causes this systematic effect. Subtracting the longitude-dependent east-west travel times, obtained along the equatorial area, from the latitude-dependent north-south travel times, obtained along the central meridian area, gives remarkably similar results for different observables. We suggest this as an effective procedure for removing the systematic center-to-limb variation. The subsurface meridional flows obtained from inversion of the corrected travel times are approximately 10 m s{sup -1} slower than those obtained without removing the systematic effect. The detected center-to-limb variation may have important implications in the derivation of meridional flows in the deep interior and needs to be better understood.

  16. SYSTEMATIC CENTER-TO-LIMB VARIATION IN MEASURED HELIOSEISMIC TRAVEL TIMES AND ITS EFFECT ON INFERENCES OF SOLAR INTERIOR MERIDIONAL FLOWS

    International Nuclear Information System (INIS)

    Zhao Junwei; Nagashima, Kaori; Bogart, R. S.; Kosovichev, A. G.; Duvall, T. L. Jr.

    2012-01-01

    We report on a systematic center-to-limb variation in measured helioseismic travel times, which must be taken into account for an accurate determination of solar interior meridional flows. The systematic variation, found in time-distance helioseismology analysis using SDO/HMI and SDO/AIA observations, is different in both travel-time magnitude and variation trend for different observables. It is not clear what causes this systematic effect. Subtracting the longitude-dependent east-west travel times, obtained along the equatorial area, from the latitude-dependent north-south travel times, obtained along the central meridian area, gives remarkably similar results for different observables. We suggest this as an effective procedure for removing the systematic center-to-limb variation. The subsurface meridional flows obtained from inversion of the corrected travel times are approximately 10 m s –1 slower than those obtained without removing the systematic effect. The detected center-to-limb variation may have important implications in the derivation of meridional flows in the deep interior and needs to be better understood.

  17. Systematic Center-To-Limb Variation in Measured Helioseismic Travel Times and Its Effect on Inferences of Solar Interior Meridional Flows

    Science.gov (United States)

    Zhao, Junwei; Nagashima, Kaori; Bogart, R. S.; Kosovichev, Alexander; Duvall, T. L., Jr.

    2012-01-01

    We report on a systematic center-to-limb variation in measured helioseismic travel times, which must be taken into account for an accurate determination of solar interior meridional flows. The systematic variation, found in time-distance helioseismology analysis using SDO/HMI and SDO/AIA observations, is different in both travel-time magnitude and variation trend for different observables. It is not clear what causes this systematic effect. Subtracting the longitude-dependent east-west travel times, obtained along the equatorial area, from the latitude-dependent north-south travel times, obtained along the central meridian area, gives remarkably similar results for different observables. We suggest this as an effective procedure for removing the systematic center-to-limb variation. The subsurface meridional flows obtained from inversion of the corrected travel times are approximately 10 m s-1 slower than those obtained without removing the systematic effect. The detected center-to-limb variation may have important implications in the derivation of meridional flows in the deep interior and needs to be better understood.

  18. Numerical analysis of flow in ultra micro centrifugal compressor -influence of meridional configuration

    Science.gov (United States)

    Kaneko, Masanao; Tsujita, Hoshio; Hirano, Toshiyuki

    2013-04-01

    A single stage ultra micro centrifugal compressor constituting ultra micro gas turbine is required to operate at high rotational speed in order to achieve the pressure ratio which establishes the gas turbine cycle. As a consequence, the aerodynamic losses can be increased by the interaction of a shock wave with the boundary layer on the blade surface. Moreover, the centrifugal force which exceeds the allowable stress of the impeller material can act on the root of blades. On the other hand, the restrictions of processing technology for the downsizing of impeller not only relatively enlarge the size of tip clearance but also make it difficult to shape the impeller with the three-dimensional blade. Therefore, it is important to establish the design technology for the impeller with the two-dimensional blade which possesses the sufficient aerodynamic performance and enough strength to bear the centrifugal force caused by the high rotational speed. In this study, the flow in two types of impeller with the two-dimensional blade which have different meridional configuration was analyzed numerically. The computed results clarified the influence of the meridional configuration on the loss generations in the impeller passage.

  19. Overturn of the Oceasn Flow in the North Atlantic as a Trigger of Inertia Motion to Form a Meridional Ocean Circulation

    Science.gov (United States)

    Nakamura, Shigehisa

    2010-05-01

    This work is an introduction of a meridional ocean circulation. As for the zonal motions,there have been many contributions. Recent oceanographic works noticed an overturn of the ocean current in the North Atlantic. The author notices this overturn is a trigger to generate a meridional ocean circulation to have a track through the deep Atlantic, the deep circum-polar current, the deep branch flow to the Pacific between the Australian and the South America. The east part of the branch flow relates to the upwelling off Peru, and the west part relates to form a deep water in the Northwest Pacific. THe overturn of the North Atlantic suggests an outflow of the deep water and a storage of the old aged deep water in the Northwest Pacific. The storage water increase in the Northwest Pacific shoould be a trigger of the swelling up of the sea level mid Pacific to affect to the ocean front variations between the coastal waters and the ocean water. In order to keep a hydrodynamic balance on the earth, an increase of the deep water in the Pacific should flow through the Bering Sea and the Arctic Sea to get to the North Atlantic. It should be noted that a budget of the ocean water flow must be hold the condition of the water masses concservation on the earth surface. This inertia motion is maintained once induced after any natural effect or some man-made influences. At this stage, the author has to notice that there has been developed a meridional inertia path of the air particle as well as the ocean water parcel, nevertheless nobody has had pointed out this inertiamotion with a meridional path in the ocean. Air-sea interaction must be one of the main factors for driving the ocean water though the inertia motion in the global scale is more energetic. To the details, the scientists should pursue what geophysical dynamics must be developed in the future.

  20. Understanding The Behavior Of The Sun'S Large Scale Magnetic Field And Its Relation With The Meridional Flow

    Science.gov (United States)

    Hazra, Gopal

    2018-02-01

    In this thesis, various studies leading to better understanding of the 11-year solar cycle and its theoretical modeling with the flux transport dynamo model are performed. Although this is primarily a theoretical thesis, there is a part dealing with the analysis of observational data. The various proxies of solar activity (e.g., sunspot number, sunspot area and 10.7 cm radio flux) from various observatory including the sunspot area records of Kodaikanal Observatory have been analyzed to study the irregular aspects of solar cycles and an analysis has been carried out on the correlation between the decay rate and the next cycle amplitude. The theoretical analysis starts with explaining how the magnetic buoyancy has been treated in the flux transport dynamo models, and advantages and disadvantages of different treatments. It is found that some of the irregular properties of the solar cycle in the decaying phase can only be well explained using a particular treatment of the magnetic buoyancy. Next, the behavior of the dynamo with the different spatial structures of the meridional flow based on recent helioseismology results has been studied. A theoretical model is constructed considering the back reaction due to the Lorentz force on the meridional flows which explains the observed variation of the meridional flow with the solar cycle. Finally, some results with 3D FTD models are presented. This 3D model is developed to handle the Babcock-Leighton mechanism and magnetic buoyancy more realistically than previous 2D models and can capture some important effects connected with the subduction of the magnetic field in polar regions, which are missed in 2D surface flux transport models. This 3D model is further used to study the evolution of the magnetic fields due to a turbulent non-axisymmetric velocity field and to compare the results with the results obtained by using a simple turbulent diffusivity coefficient.

  1. MERIDIONAL CIRCULATION DYNAMICS FROM 3D MAGNETOHYDRODYNAMIC GLOBAL SIMULATIONS OF SOLAR CONVECTION

    International Nuclear Information System (INIS)

    Passos, Dário; Charbonneau, Paul; Miesch, Mark

    2015-01-01

    The form of solar meridional circulation is a very important ingredient for mean field flux transport dynamo models. However, a shroud of mystery still surrounds this large-scale flow, given that its measurement using current helioseismic techniques is challenging. In this work, we use results from three-dimensional global simulations of solar convection to infer the dynamical behavior of the established meridional circulation. We make a direct comparison between the meridional circulation that arises in these simulations and the latest observations. Based on our results, we argue that there should be an equatorward flow at the base of the convection zone at mid-latitudes, below the current maximum depth helioseismic measures can probe (0.75 R ⊙ ). We also provide physical arguments to justify this behavior. The simulations indicate that the meridional circulation undergoes substantial changes in morphology as the magnetic cycle unfolds. We close by discussing the importance of these dynamical changes for current methods of observation which involve long averaging periods of helioseismic data. Also noteworthy is the fact that these topological changes indicate a rich interaction between magnetic fields and plasma flows, which challenges the ubiquitous kinematic approach used in the vast majority of mean field dynamo simulations

  2. Predictability of Returns and Cash Flows

    OpenAIRE

    Ralph S.J. Koijen; Stijn Van Nieuwerburgh

    2010-01-01

    We review the literature on return and cash-flow growth predictability from the perspective of the present-value identity. We focus predominantly on recent work. Our emphasis is on U.S. aggregate stock return predictability, but we also discuss evidence from other asset classes and countries.

  3. Better understanding flow-restricted environments from hideout return analyses

    International Nuclear Information System (INIS)

    Ollar, Ph.; Viricel-Honorez, L.

    1998-01-01

    Understanding and controlling the chemical phenomena in flow-restricted areas of the secondary side of steam generators (SG) is a key point in fighting against corrosion (IGA) in these areas. Hence, more than 150 hideout returns from French plants are used to assess the chemical environment in flow-restricted areas. The influence of several parameters such as tube support plates design, SG blowdown flowrate and temperature at the end of hideout returns, on returned weights and on flow-restricted environments predicted by modelling are examined. A correlation between different operating and returned chemistry indexes (molar ratios), and IGA is sought: no link is found between IGA and Na/Cl molar ratio at the beginning of hideout returns. However, as IGA extends, the returned weights of sodium and chloride seem to decrease, suggesting a greater hideout and a lower hideout return efficiency, perhaps due to SG fouling, and/or a smaller hideout/hideout return thanks to an improved operating chemistry. Using the pH computed from hideout return data as an index for the presence of IGA is also studied: no correlation is found between the two. Improving plants chemistry is finally proposed, based on an optimization of hideout returns. (authors)

  4. ESTIMATING THE DEEP SOLAR MERIDIONAL CIRCULATION USING MAGNETIC OBSERVATIONS AND A DYNAMO MODEL: A VARIATIONAL APPROACH

    Energy Technology Data Exchange (ETDEWEB)

    Hung, Ching Pui; Jouve, Laurène; Brun, Allan Sacha [Laboratoire AIM Paris-Saclay, CEA/IRFU Université Paris-Diderot CNRS/INSU, F-91191 Gif-Sur-Yvette (France); Fournier, Alexandre [Institut de Physique du Globe de Paris, Sorbonne Paris Cité, Université Paris Diderot UMR 7154 CNRS, F-75005 Paris (France); Talagrand, Olivier [Laboratoire de météorologie dynamique, UMR 8539, Ecole Normale Supérieure, Paris Cedex 05 (France)

    2015-12-01

    We show how magnetic observations of the Sun can be used in conjunction with an axisymmetric flux-transport solar dynamo model in order to estimate the large-scale meridional circulation throughout the convection zone. Our innovative approach rests on variational data assimilation, whereby the distance between predictions and observations (measured by an objective function) is iteratively minimized by means of an optimization algorithm seeking the meridional flow that best accounts for the data. The minimization is performed using a quasi-Newton technique, which requires knowledge of the sensitivity of the objective function to the meridional flow. That sensitivity is efficiently computed via the integration of the adjoint flux-transport dynamo model. Closed-loop (also known as twin) experiments using synthetic data demonstrate the validity and accuracy of this technique for a variety of meridional flow configurations, ranging from unicellular and equatorially symmetric to multicellular and equatorially asymmetric. In this well-controlled synthetic context, we perform a systematic study of the behavior of our variational approach under different observational configurations by varying their spatial density, temporal density, and noise level, as well as the width of the assimilation window. We find that the method is remarkably robust, leading in most cases to a recovery of the true meridional flow to within better than 1%. These encouraging results are a first step toward using this technique to (i) better constrain the physical processes occurring inside the Sun and (ii) better predict solar activity on decadal timescales.

  5. ESTIMATING THE DEEP SOLAR MERIDIONAL CIRCULATION USING MAGNETIC OBSERVATIONS AND A DYNAMO MODEL: A VARIATIONAL APPROACH

    International Nuclear Information System (INIS)

    Hung, Ching Pui; Jouve, Laurène; Brun, Allan Sacha; Fournier, Alexandre; Talagrand, Olivier

    2015-01-01

    We show how magnetic observations of the Sun can be used in conjunction with an axisymmetric flux-transport solar dynamo model in order to estimate the large-scale meridional circulation throughout the convection zone. Our innovative approach rests on variational data assimilation, whereby the distance between predictions and observations (measured by an objective function) is iteratively minimized by means of an optimization algorithm seeking the meridional flow that best accounts for the data. The minimization is performed using a quasi-Newton technique, which requires knowledge of the sensitivity of the objective function to the meridional flow. That sensitivity is efficiently computed via the integration of the adjoint flux-transport dynamo model. Closed-loop (also known as twin) experiments using synthetic data demonstrate the validity and accuracy of this technique for a variety of meridional flow configurations, ranging from unicellular and equatorially symmetric to multicellular and equatorially asymmetric. In this well-controlled synthetic context, we perform a systematic study of the behavior of our variational approach under different observational configurations by varying their spatial density, temporal density, and noise level, as well as the width of the assimilation window. We find that the method is remarkably robust, leading in most cases to a recovery of the true meridional flow to within better than 1%. These encouraging results are a first step toward using this technique to (i) better constrain the physical processes occurring inside the Sun and (ii) better predict solar activity on decadal timescales

  6. Identification of flow paths and quantification of return flow volumes and timing at field scale

    Science.gov (United States)

    Claes, N.; Paige, G. B.; Parsekian, A.

    2017-12-01

    Flood irrigation, which constitutes a large part of agricultural water use, accounts for a significant amount of the water that is diverted from western streams. Return flow, the portion of the water applied to irrigated areas that returns to the stream, is important for maintaining base flows in streams and ecological function of riparian zones and wetlands hydrologically linked with streams. Prediction of timing and volumes of return flow during and after flood irrigation pose a challenge due to the heterogeneity of pedogenic and soil physical factors that influence vadose zone processes. In this study, we quantify volumes of return flow and potential pathways in the subsurface through a vadose zone flow model that is informed by both hydrological and geophysical observations in a Bayesian setting. We couple a two-dimensional vadose zone flow model through a Bayesian Markov Chain Monte Carlo approach with time lapse ERT, borehole NMR datasets that are collected during and after flood irrigation experiments, and soil physical lab analysis. The combination of both synthetic models and field observations leads to flow path identification and allows for quantification of volumes and timing and associated uncertainties of subsurface return that stems from flood irrigation. The quantification of the impact of soil heterogeneity enables us to translate these results to other sites and predict return flow under different soil physical settings. This is key when managing irrigation water resources and predictions of outcomes of different scenarios have to be evaluated.

  7. A Numerical Study on the Impeller Meridional Curvature of High Pressure Multistage Pump

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Deok Su; Jean, Sang Gyu; Mamatov, Sanjar [Hyosung Goodsprings, Inc., Busan (Korea, Republic of); Park, Warn Gyu [Pusan Nat’l Univ., Busan (Korea, Republic of)

    2017-07-15

    This paper presents the hydraulic design an impeller and radial diffuser of a high-pressure multistage pump for reverse osmosis. The flow distribution and hydraulic performance for the meridional design of the impeller were analyzed numerically. Optimization was conducted based on the response surface method by varying the hub and shroud meridional curvatures, while maintaining the impeller outlet diameter, outlet width, and eye diameter constant. The analysis results of the head and efficiency with the variation in the impeller meridional profile showed that angle of the front shroud near the impeller outlet (εDs) had the highest effect on head increase, while the hub inlet length (d1i) and shroud curvature (Rds) had the highest effect on efficiency. From the meridional profile variation, an approximately 0.5% increase in efficiency was observed compared with the base model (case 25).

  8. Fueling export production: nutrient return pathways from the deep ocean and their dependence on the Meridional Overturning Circulation

    Science.gov (United States)

    Palter, J. B.; Sarmiento, J. L.; Gnanadesikan, A.; Simeon, J.; Slater, R. D.

    2010-11-01

    In the Southern Ocean, mixing and upwelling in the presence of heat and freshwater surface fluxes transform subpycnocline water to lighter densities as part of the upward branch of the Meridional Overturning Circulation (MOC). One hypothesized impact of this transformation is the restoration of nutrients to the global pycnocline, without which biological productivity at low latitudes would be significantly reduced. Here we use a novel set of modeling experiments to explore the causes and consequences of the Southern Ocean nutrient return pathway. Specifically, we quantify the contribution to global productivity of nutrients that rise from the ocean interior in the Southern Ocean, the northern high latitudes, and by mixing across the low latitude pycnocline. In addition, we evaluate how the strength of the Southern Ocean winds and the parameterizations of subgridscale processes change the dominant nutrient return pathways in the ocean. Our results suggest that nutrients upwelled from the deep ocean in the Antarctic Circumpolar Current and subducted in Subantartic Mode Water support between 33 and 75% of global export production between 30° S and 30° N. The high end of this range results from an ocean model in which the MOC is driven primarily by wind-induced Southern Ocean upwelling, a configuration favored due to its fidelity to tracer data, while the low end results from an MOC driven by high diapycnal diffusivity in the pycnocline. In all models, nutrients exported in the SAMW layer are utilized and converted rapidly (in less than 40 years) to remineralized nutrients, explaining previous modeling results that showed little influence of the drawdown of SAMW surface nutrients on atmospheric carbon concentrations.

  9. Fueling export production: nutrient return pathways from the deep ocean and their dependence on the Meridional Overturning Circulation

    Directory of Open Access Journals (Sweden)

    J. B. Palter

    2010-11-01

    Full Text Available In the Southern Ocean, mixing and upwelling in the presence of heat and freshwater surface fluxes transform subpycnocline water to lighter densities as part of the upward branch of the Meridional Overturning Circulation (MOC. One hypothesized impact of this transformation is the restoration of nutrients to the global pycnocline, without which biological productivity at low latitudes would be significantly reduced. Here we use a novel set of modeling experiments to explore the causes and consequences of the Southern Ocean nutrient return pathway. Specifically, we quantify the contribution to global productivity of nutrients that rise from the ocean interior in the Southern Ocean, the northern high latitudes, and by mixing across the low latitude pycnocline. In addition, we evaluate how the strength of the Southern Ocean winds and the parameterizations of subgridscale processes change the dominant nutrient return pathways in the ocean. Our results suggest that nutrients upwelled from the deep ocean in the Antarctic Circumpolar Current and subducted in Subantartic Mode Water support between 33 and 75% of global export production between 30° S and 30° N. The high end of this range results from an ocean model in which the MOC is driven primarily by wind-induced Southern Ocean upwelling, a configuration favored due to its fidelity to tracer data, while the low end results from an MOC driven by high diapycnal diffusivity in the pycnocline. In all models, nutrients exported in the SAMW layer are utilized and converted rapidly (in less than 40 years to remineralized nutrients, explaining previous modeling results that showed little influence of the drawdown of SAMW surface nutrients on atmospheric carbon concentrations.

  10. Fueling primary productivity: nutrient return pathways from the deep ocean and their dependence on the Meridional Overturning Circulation

    Science.gov (United States)

    Palter, J. B.; Sarmiento, J. L.; Gnanadesikan, A.; Simeon, J.; Slater, D.

    2010-06-01

    In the Southern Ocean, mixing and upwelling in the presence of heat and freshwater surface fluxes transform subpycnocline water to lighter densities as part of the upward branch of the Meridional Overturning Circulation (MOC). One hypothesized impact of this transformation is the restoration of nutrients to the global pycnocline, without which biological productivity at low latitudes would be catastrophically reduced. Here we use a novel set of modeling experiments to explore the causes and consequences of the Southern Ocean nutrient return pathway. Specifically, we quantify the contribution to global productivity of nutrients that rise from the ocean interior in the Southern Ocean, the northern high latitudes, and by mixing across the low latitude pycnocline. In addition, we evaluate how the strength of the Southern Ocean winds and the parameterizations of subgridscale processes change the dominant nutrient return pathways in the ocean. Our results suggest that nutrients upwelled from the deep ocean in the Antarctic Circumpolar Current and subducted in Subantartic Mode Water support between 33 and 75% of global primary productivity between 30° S and 30° N. The high end of this range results from an ocean model in which the MOC is driven primarily by wind-induced Southern Ocean upwelling, a configuration favored due to its fidelity to tracer data, while the low end results from an MOC driven by high diapycnal diffusivity in the pycnocline. In all models, the high preformed nutrients subducted in the SAMW layer are converted rapidly (in less than 40 years) to remineralized nutrients, explaining previous modeling results that showed little influence of the drawdown of SAMW surface nutrients on atmospheric carbon concentrations.

  11. Radial Transport and Meridional Circulation in Accretion Disks

    Energy Technology Data Exchange (ETDEWEB)

    Philippov, Alexander A. [Department of Astrophysical Sciences, Princeton University, Ivy Lane, Princeton, NJ 08540 (United States); Rafikov, Roman R., E-mail: sashaph@princeton.edu [Institute for Advanced Study, Einstein Drive, Princeton, NJ 08540 (United States)

    2017-03-10

    Radial transport of particles, elements and fluid driven by internal stresses in three-dimensional (3D) astrophysical accretion disks is an important phenomenon, potentially relevant for the outward dust transport in protoplanetary disks, origin of the refractory particles in comets, isotopic equilibration in the Earth–Moon system, etc. To gain better insight into these processes, we explore the dependence of meridional circulation in 3D disks with shear viscosity on their thermal stratification, and demonstrate a strong effect of the latter on the radial flow. Previous locally isothermal studies have normally found a pattern of the radial outflow near the midplane, switching to inflow higher up. Here we show, both analytically and numerically, that a flow that is inward at all altitudes is possible in disks with entropy and temperature steeply increasing with height. Such thermodynamic conditions may be typical in the optically thin, viscously heated accretion disks. Disks in which these conditions do not hold should feature radial outflow near the midplane, as long as their internal stress is provided by the shear viscosity. Our results can also be used for designing hydrodynamical disk simulations with a prescribed pattern of the meridional circulation.

  12. Model based flow measurement using venturi flumes for return flow during drilling

    Directory of Open Access Journals (Sweden)

    Ivan Pirir

    2017-07-01

    Full Text Available In an oil well drilling operation, a proper knowledge of the return fluid flowrate is necessary both for the stabilization of the bottom hole pressure of the well and also as a primary indication of a kick or loss. In practice, the drill fluid flowing through the return line is usually measured with Coriolis meters. However this method is both expensive and has some downsides. For instance there is a risk of blockage due to drill cuttings while measuring the discharge. The presence of gas and cuttings in the drilling fluid will also have a negative effect in the measurement i.e. for multi-phase fluid, the readings from Coriolis meters may not be accurate. A cheaper alternative would be to use an open channel for the measurement of the discharge from the return flowline. In this paper, a venturi rig is used as the open channel and modeled by the Saint Venant equations. Experimental verification of the simulation results show a promising behavior of the model based measurement of the return fluid flow.

  13. Meridional Considerations of the Centrifugal Compressor Development

    Directory of Open Access Journals (Sweden)

    C. Xu

    2012-01-01

    Full Text Available Centrifugal compressor developments are interested in using optimization procedures that enable compressor high efficiency and wide operating ranges. Recently, high pressure ratio and efficiency of the centrifugal compressors require impeller design to pay attention to both the blade angle distribution and the meridional profile. The geometry of the blades and the meridional profile are very important contributions of compressor performance and structure reliability. This paper presents some recent studies of meridional impacts of the compressor. Studies indicated that the meridional profiles of the impeller impact the overall compressor efficiency and pressure ratio at the same rotational speed. Proper meridional profiles can improve the compressor efficiency and increase the overall pressure ratio at the same blade back curvature.

  14. An electrical analogy relating the Atlantic multidecadal oscillation to the Atlantic meridional overturning circulation.

    Directory of Open Access Journals (Sweden)

    Bruce E Kurtz

    Full Text Available The Atlantic meridional overturning circulation (AMOC is the northward flow of surface water to subpolar latitudes where deepwater is formed, balanced by southward abyssal flow and upwelling in the vicinity of the Southern Ocean. It is generally accepted that AMOC flow oscillates with a period of 60-80 years, creating a regular variation in North Atlantic sea surface temperature known as the Atlantic multidecadal oscillation (AMO. This article attempts to answer two questions: how is the AMOC driven and why does it oscillate? Using methods commonly employed by chemical engineers for analyzing processes involving flowing liquids, apparently not previously applied to trying to understand the AMOC, an equation is developed for AMOC flow as a function of the meridional density gradient or the corresponding temperature gradient. The equation is based on the similarity between the AMOC and an industrial thermosyphon loop cooler, which circulates a heat transfer liquid without using a mechanical pump. Extending this equation with an analogy between the flow of heat and electricity explains why the AMOC flow oscillates and what determines its period. Calculated values for AMOC flow and AMO oscillation period are in good agreement with measured values.

  15. Intra-seasonal Oscillations (ISO of zonal-mean meridional winds and temperatures as measured by UARS

    Directory of Open Access Journals (Sweden)

    F. T. Huang

    2005-06-01

    Full Text Available Based on an empirical analysis of measurements with the High Resolution Doppler Imager (HRDI on the UARS spacecraft in the upper mesosphere (95km, persistent and regular intra-seasonal oscillations (ISO with periods of about 2 to 4 months have recently been reported in the zonal-mean meridional winds. Similar oscillations have also been discussed independently in a modeling study, and they were attributed to wave-mean-flow interactions. The observed and modeled meridional wind ISOs were largely confined to low latitudes. We report here on an analysis of concurrent UARS temperature measurements, which produces oscillations similar to those seen in the meridional winds. Although the temperature oscillations are observed at lower altitudes (55km, their phase variations with latitude are qualitatively consistent with the inferred properties seen in the meridional winds and thus provide independent evidence for the existence of ISOs in the mesosphere.

  16. Analisis Return Flow antar Bendung (Studi Kasus Bendung Klampok-Plakaran dan Bendung Sekarsuli

    Directory of Open Access Journals (Sweden)

    Cut Dwi Refika

    2016-04-01

    Full Text Available Return flow occures when the intake flow for irrigation is not utilized and return back to the river, whether by runoff or seepage. This study focused on Klampok-Plakaran and Sekarsuli weirs in Sleman Regency Special Region of Yogyakarta. The return flow analysis was carried out by using the Tank Model. The model was adjusted to the field condition, such as paddy fields, cane plantation and fish ponds. Parameters in the Tank Model were the output coefficient from the side flow and below, and the height of storage in the tank. Output from the side of the tank consisted of runoffs and seepage, which were the return flow value. The Tank Model was calibrated and verified to obtain the most proper Tank Model suitable to the condition on field. The accuracy indicators consists of correlation coefficient (R, Volume Error (VE, and Root Mean Square Error (RMSE of 0,97; 5,00 % and 0,03, respectively. Values of return flow during the cultivation season I (October - January, cultivation season II (February - Mei and cultivation season III (June - September were 67,06%, 24,05% and 21,38%, respectively. Model verification parameters were carried out on cultivation season 2009-2010. Value accuracy for the correlation coefficient (R, Volume Error (VE and root mean square error (RMSE are 0,81; 5,20 dan 0,14 respectively.

  17. The role of meridional density differences for a wind-driven overturning circulation

    Energy Technology Data Exchange (ETDEWEB)

    Schewe, J.; Levermann, A. [Potsdam Institute for Climate Impact Research, Earth System Analysis, Potsdam (Germany); Potsdam University, Physics Institute, Potsdam (Germany)

    2010-03-15

    Experiments with the coupled climate model CLIMBER-3{alpha}, which contains an oceanic general circulation model, show deep upwelling in the Southern Ocean to be proportional to the surface wind stress in the latitudinal band of Drake Passage. At the same time, the distribution of the Southern Ocean upwelling onto the oceanic basins is controlled by buoyancy distribution; the inflow into each basin being proportional to the respective meridional density difference. We observe approximately the same constant of proportionality for all basins, and demonstrate that it can be directly related to the flow geometry. For increased wind stress in the Southern Ocean, the overturning increases both in the Atlantic and the Indo-Pacific basin. For strongly reduced wind stress, the circulation enters a regime where Atlantic overturning is maintained through Pacific upwelling, in order to satisfy the transports set by the density differences. Previous results on surface buoyancy and wind stress forcing, obtained with different models, are reproduced within one model in order to distill a consistent picture. We propose that both Southern Ocean upwelling and meridional density differences set up a system of conditions that determine the global meridional overturning circulation. (orig.)

  18. Control-flow analysis of function calls and returns by abstract interpretation

    DEFF Research Database (Denmark)

    Midtgaard, Jan; Jensen, Thomas P.

    2009-01-01

    We derive a control-flow analysis that approximates the interprocedural control-flow of both function calls and returns in the presence of first-class functions and tail-call optimization. In addition to an abstract environment, our analysis computes for each expression an abstract control stack......, effectively approximating where function calls return across optimized tail calls. The analysis is systematically calculated by abstract interpretation of the stack-based CaEK abstract machine of Flanagan et al. using a series of Galois connections. Abstract interpretation provides a unifying setting in which...

  19. Role of the meridional dipole of SSTA and associated cross-equatorial flow in the tropical eastern Pacific in terminating the 2014 El Niño development

    Science.gov (United States)

    Wu, Yi-Kai; Chen, Lin; Hong, Chi-Cherng; Li, Tim; Chen, Cheng-Ta; Wang, Lu

    2018-03-01

    In the boreal spring of 2014, the oceanic and atmospheric conditions were favorable for an El Niño's development. It was predicted that in 2014, a super El Niño or at least a regular El Niño with normal magnitude, would initiate. However, the growth rate of the sea surface temperature anomaly (SSTA) in the equatorial eastern Pacific suddenly declined in the boreal summer. The physical processes responsible for the termination of the 2014 El Niño were addressed in this study. We hypothesized that a meridional dipole of SSTA, characterized by a pronounced warm SSTA over the eastern North Pacific (ENP) and cold SSTA over the eastern South Pacific (ESP), played a crucial role in blocking the 2014 El Niño's development. The observational analysis revealed that the meridional dipole of SSTA and the relevant anomalous cross-equatorial flow in the tropical eastern Pacific, induced anomalous westward ({u^' }0) currents in the equatorial eastern Pacific, leading to negative anomalous zonal advection term (- {u^' }partial \\overline T /partial xpartial \\overline T /partial znegative SSTA tendency in the boreal summer, and thus killed off the budding 2014 El Niño. The idealized numerical experiments further confirmed that the 2014 El Niño's development could be suppressed by the meridional dipole of SSTA, and both the ENP pole and ESP pole make a contribution.

  20. A study on the relationship between operational cash flow and the return of stockholders

    Directory of Open Access Journals (Sweden)

    Hassan Ghodrati

    2014-07-01

    Full Text Available Performance measurement in managerial accounting is normally associated with cash flow and it is executed based on different figures such as testing information content abuse and accounting figures. However, increasing the information content in accrual components of earning and internal performance measurement provides additional informative insights. This paper studies the relationship between operating cash flows and earnings along with total shareholder returns. The study chooses the information of 54 firms from Tehran Stock Exchange. The results show that there were some meaningful relationship between the operating cash flow, profitability and the returns of all stakeholders. However, this happens by increasing profitability and cash flow of information asymmetry proportion to their correlation with the economic efficiency of shareholders’ returns.

  1. Rates of Return on Flow-Through Shares: Investors and Governments Beware

    Directory of Open Access Journals (Sweden)

    Vijay Jog

    2016-02-01

    Full Text Available Canada’s tax code allows the use of flow-through shares for mining and oil and gas companies on the assumption that they are a good way to spur new productive exploration and are also beneficial to investors. In reality, it appears that flow-through shares are lousy for both. Flow-through shares are designed for corporations that cannot make good use of expense deductions from their taxes and so, through the use of these special type of shares, can pass along their expenses for shareholders to deduct from their own income taxes. This tax break is not insignificant: The amount of revenue foregone by the federal government due to flow-through shares and the related Mineral Exploration Tax Credit averaged $440 million every year between 2007 and 2012. But the steepest price has arguably been borne by investors, with returns on flow-through shares performing extraordinarily poorly. For small companies that issued these shares, the annualized absolute return was a nearly 100 per cent loss. For larger companies, the returns were not as bad — negative 14 per cent — but still a loss. And if adjusted for corresponding benchmarks, the returns were even worse. From the $2.5 billion raised from Canadians using flow-through shares, investors have lost $1.2 billion. Certainly these results would indicate that flow-through shares are hardly helping Canadian explorers strike lucrative new discoveries (it is impossible to say whether the limited success some larger companies had in locating productive assets, using flow-through shares, would not have occurred anyway. Meanwhile, these share issues, bearing the imprimatur of a special government right and the incentive of an investor tax benefit, have likely led to market distortions, luring capital that might have otherwise gone to more productive and rewarding investments. Compounding matters is the very real possibility that those projects that were funded by flow-through shares, but would have been

  2. Foreign portfolio capital flows and stock returns: a study of Brazilian listed firms

    Directory of Open Access Journals (Sweden)

    Tiago Rodrigues Loncan

    2015-12-01

    Full Text Available Abstract This study analyzed the effect of foreign portfolio capital flows on stock returns of Brazilian listed firms through a 6-factors APT model, in which an additional risk factor for foreign portfolio capital flows was included. First, an aggregate analysis was conducted. The partial effect of foreign portfolio capital flows on the IBOVESPA index’s returns was statistically significant and positive. Next, a disaggregate analysis was also implemented, in which portfolios of stocks were sorted by sector of economic activity, level of risk and level of corporate governance. Foreign portfolio capitals caused increases in returns especially for sectors related to commodities, industry and cyclical consumption. For the portfolios sorted by risk (in which the stocks’ betas were used as a risk parameter for sorting, foreign capitals increased the returns of mid-high and high beta portfolios, but decreased the returns of low and low-mid beta portfolios. For corporate governance portfolios, the firms listed on the Novo Mercado segment (according to BMF&Bovespa criteria experienced a statistically significant revaluation effect. Overall, the results of the study provide support to the revaluation effect hypothesis.

  3. Cross section of equity returns and assets’ fundamental cash-flow risk

    NARCIS (Netherlands)

    Galsband, V.

    2010-01-01

    The decomposition of consumption beta into a component driven by assets' cash-flow news and one related to assets' discount-rate news reveals that macroeconomic risks embodied in cash flows largely account for the cross-sectional dynamics of average stock returns. Empirically, we find that

  4. A BABCOCK–LEIGHTON SOLAR DYNAMO MODEL WITH MULTI-CELLULAR MERIDIONAL CIRCULATION IN ADVECTION- AND DIFFUSION-DOMINATED REGIMES

    Energy Technology Data Exchange (ETDEWEB)

    Belucz, Bernadett; Forgács-Dajka, Emese [Eötvös University, Department of Astronomy, 1518 Budapest, Pf. 32 (Hungary); Dikpati, Mausumi, E-mail: bbelucz@astro.elte.hu, E-mail: dikpati@ucar.edu [High Altitude Observatory, National Center for Atmospheric Research, 3080 Center Green, Boulder, CO 80307-3000 (United States)

    2015-06-20

    Babcock–Leighton type-solar dynamo models with single-celled meridional circulation are successful in reproducing many solar cycle features. Recent observations and theoretical models of meridional circulation do not indicate a single-celled flow pattern. We examine the role of complex multi-cellular circulation patterns in a Babcock–Leighton solar dynamo in advection- and diffusion-dominated regimes. We show from simulations that the presence of a weak, second, high-latitude reverse cell speeds up the cycle and slightly enhances the poleward branch in the butterfly diagram, whereas the presence of a second cell in depth reverses the tilt of the butterfly wing to an antisolar type. A butterfly diagram constructed from the middle of convection zone yields a solar-like pattern, but this may be difficult to realize in the Sun because of magnetic buoyancy effects. Each of the above cases behaves similarly in higher and lower magnetic diffusivity regimes. However, our dynamo with a meridional circulation containing four cells in latitude behaves distinctly differently in the two regimes, producing solar-like butterfly diagrams with fast cycles in the higher diffusivity regime, and complex branches in butterfly diagrams in the lower diffusivity regime. We also find that dynamo solutions for a four-celled pattern, two in radius and two in latitude, prefer to quickly relax to quadrupolar parity if the bottom flow speed is strong enough, of similar order of magnitude as the surface flow speed.

  5. A BABCOCK–LEIGHTON SOLAR DYNAMO MODEL WITH MULTI-CELLULAR MERIDIONAL CIRCULATION IN ADVECTION- AND DIFFUSION-DOMINATED REGIMES

    International Nuclear Information System (INIS)

    Belucz, Bernadett; Forgács-Dajka, Emese; Dikpati, Mausumi

    2015-01-01

    Babcock–Leighton type-solar dynamo models with single-celled meridional circulation are successful in reproducing many solar cycle features. Recent observations and theoretical models of meridional circulation do not indicate a single-celled flow pattern. We examine the role of complex multi-cellular circulation patterns in a Babcock–Leighton solar dynamo in advection- and diffusion-dominated regimes. We show from simulations that the presence of a weak, second, high-latitude reverse cell speeds up the cycle and slightly enhances the poleward branch in the butterfly diagram, whereas the presence of a second cell in depth reverses the tilt of the butterfly wing to an antisolar type. A butterfly diagram constructed from the middle of convection zone yields a solar-like pattern, but this may be difficult to realize in the Sun because of magnetic buoyancy effects. Each of the above cases behaves similarly in higher and lower magnetic diffusivity regimes. However, our dynamo with a meridional circulation containing four cells in latitude behaves distinctly differently in the two regimes, producing solar-like butterfly diagrams with fast cycles in the higher diffusivity regime, and complex branches in butterfly diagrams in the lower diffusivity regime. We also find that dynamo solutions for a four-celled pattern, two in radius and two in latitude, prefer to quickly relax to quadrupolar parity if the bottom flow speed is strong enough, of similar order of magnitude as the surface flow speed

  6. Water temperature in irrigation return flow from the Upper Snake Rock watershed

    Science.gov (United States)

    Water returning to a river from an irrigated watershed could increase the water temperature in the river. The objective of this study was to compare the temperature of irrigation return flow water with the temperature of the diverted irrigation water. Water temperature was measured weekly in the mai...

  7. Flow regime visualization and pressure drops of HFO-1234yf, R-134a and R-410A during downward two-phase flow in vertical return bends

    International Nuclear Information System (INIS)

    Padilla, Miguel; Revellin, Rémi; Wallet, Jérémy; Bonjour, Jocelyn

    2013-01-01

    Highlights: ► Visual observation of two-phase flow regimes during downward flow in a return bend. ► Bubble and vapor slug dynamical behaviors in downward slug flow are reported. ► Perturbation lengths up- and downstream of the return bend have been investigated. ► Measurement of 285 pressure drop data points for HFO-1234yf, R-134a and R-410A. -- Abstract: This paper provides a qualitative visual observation of the two-phase flow patterns for HFO-1234yf and R-134a during downward flow in a vertical 6.7 mm inner diameter glass return bend. The different flow regimes observed are: slug, intermittent and annular flows. Bubble and vapor slug dynamical behaviors in downward slug flow are reported for HFO-1234yf. In addition, to determine the perturbation lengths up- and downstream of the return bend, the total pressure drop has been measured at different pressure tap location up- and downstream of the singularity. Furthermore, 285 pressure drop data points measured for two-phase flow of HFO-1234yf, R-134a and R-410A in vertical downward flow return bends are presented. The flow behavior in the return bend, which is subjected to the complex combined actions of gravity and centrifugal force was expressed in terms of the vapor Froude number. This experimental pressure drop database, which is included in the appendix, is compared to four well-known prediction methods available in the literature

  8. Control-flow analysis of function calls and returns by abstract interpretation

    DEFF Research Database (Denmark)

    Midtgaard, Jan; Jensen, Thomas P.

    2012-01-01

    Abstract interpretation techniques are used to derive a control-flow analysis for a simple higher-order functional language. The analysis approximates the interprocedural control-flow of both function calls and returns in the presence of first-class functions and tail-call optimization. In additi...... a rational reconstruction of a constraint-based CFA from abstract interpretation principles....

  9. Adaptive Management of Return Flows: Lessons from a Case Study in Environmental Water Delivery to a Floodplain River

    Science.gov (United States)

    Wolfenden, Benjamin J.; Wassens, Skye M.; Jenkins, Kim M.; Baldwin, Darren S.; Kobayashi, Tsuyoshi; Maguire, James

    2018-03-01

    For many floodplain rivers, reinstating wetland connectivity is necessary for ecosystems to recover from decades of regulation. Environmental return flows (the managed delivery of wetland water to an adjacent river) can be used strategically to facilitate natural ecosystem connectivity, enabling the transfer of nutrients, energy, and biota from wetland habitats to the river. Using an informal adaptive management framework, we delivered return flows from a forested wetland complex into a large lowland river in south-eastern Australia. We hypothesized that return flows would (a) increase river nutrient concentrations; (b) reduce wetland nutrient concentrations; (c) increase rates of ecosystem metabolism through the addition of potentially limiting nutrients, causing related increases in the concentration of water column chlorophyll-a; and (d) increase the density and species richness of microinvertebrates in riverine benthic habitats. Our monitoring results demonstrated a small increase in the concentrations of several key nutrients but no evidence for significant ecological responses was found. Although return flows can be delivered from forested floodplain areas without risking hypoxic blackwater events, returning nutrient and carbon-rich water to increase riverine productivity is limited by the achievable scale of return flows. Nevertheless, using return flows to flush carbon from floodplains may be a useful management tool to reduce carbon loads, preparing floodplains for subsequent releases (e.g., mitigating the risk of hypoxic blackwater events). In this example, adaptive management benefited from a semi-formal collaboration between science and management that allowed for prompt decision-making.

  10. LABORATORY EVALUATION OF AIR FLOW MEASUREMENT METHODS FOR RESIDENTIAL HVAC RETURNS

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain; Stratton, Chris

    2015-02-01

    This project improved the accuracy of air flow measurements used in commissioning California heating and air conditioning systems in Title 24 (Building and Appliance Efficiency Standards), thereby improving system performance and efficiency of California residences. The research team at Lawrence Berkeley National Laboratory addressed the issue that typical tools used by contractors in the field to test air flows may not be accurate enough to measure return flows used in Title 24 applications. The team developed guidance on performance of current diagnostics as well as a draft test method for use in future evaluations. The series of tests performed measured air flow using a range of techniques and devices. The measured air flows were compared to reference air flow measurements using inline air flow meters built into the test apparatus. The experimental results showed that some devices had reasonable results (typical errors of 5 percent or less) but others had much bigger errors (up to 25 percent). Because manufacturers’ accuracy estimates for their equipment do not include many of the sources of error found in actual field measurements (and replicated in the laboratory testing in this study) it is essential for a test method that could be used to determine the actual uncertainty in this specific application. The study team prepared a draft test method through ASTM International to determine the uncertainty of air flow measurements at residential heating ventilation and air conditioning returns and other terminals. This test method, when finalized, can be used by the Energy Commission and other entities to specify required accuracy of measurement devices used to show compliance with standards.

  11. Pulling the Meridional Overturning Circulation From the South DESC0005100

    Energy Technology Data Exchange (ETDEWEB)

    Cessi, Paola [Univ. of California, San Diego, CA (United States); Wolfe, Christopher L. [Scripps Inst. of Oceanography, San Diego, CA (United States)

    2015-11-25

    This project concerned the Atlantic Meridional Overturning Circulation (AMOC), its stability, variability and sensitivity to atmospheric forcing, both mechanical (wind-stress) and thermodynamical (heat and freshwater surface fluxes). The focus of the study is the interhemispheric cell in the largely adiabatic regime, where the flow is characterized by a descending branch in the high latitudes of the North Atlantic and the upwelling branch in the Antarctic Circumpolar Current (ACC) region of the Southern Ocean. These two end points are connected by shared isopycnals along which the flow takes place. The approach is to systematically study the amplitude and frequency of the AMOC’s response to localized buoyancy with an ocean-only model in both coarse and high-resolution configurations, analyzed with innovative diagnostics, focused on the “residual overturning circulation” (ROC), which is the proper measure of the transport of heat and other tracers.

  12. Laboratory Evaluation of Air Flow Measurement Methods for Residential HVAC Returns

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain; Stratton, Chris

    2015-07-01

    This project improved the accuracy of air flow measurements used in commissioning California heating and air conditioning systems in Title 24 (Building and Appliance Efficiency Standards), thereby improving system performance and efficiency of California residences. The research team at Lawrence Berkeley National Laboratory addressed the issue that typical tools used by contractors in the field to test air flows may not be accurate enough to measure return flows used in Title 24 applications. The team developed guidance on performance of current diagnostics as well as a draft test method for use in future evaluations. The series of tests performed measured air flow using a range of techniques and devices. The measured air flows were compared to reference air flow measurements using inline air flow meters built into the test apparatus. The experimental results showed that some devices had reasonable results (typical errors of 5 percent or less) but others had much bigger errors (up to 25 percent).

  13. The ionospheric signature of transient dayside reconnection and the associated pulsed convection return flow

    Directory of Open Access Journals (Sweden)

    S. E. Milan

    Full Text Available Three SuperDARN coherent HF radars are employed to investigate the excitation of convection in the dayside high-latitude ionosphere in response to transient reconnection occurring in the cusp region. This study demonstrates the existence of transient antisunward-propagating backscatter features at the expected location of the ionospheric footprint of the cusp region, which have a repetition rate near 10 min. These are interpreted as the ionospheric signature of flux transfer events. Moreover, transient sunward-propagating regions of backscatter are observed in the convection return flow regions of both the pre- and post-noon sectors. These patches are observed to propagate towards the noon sector from at least as far around the auroral zone as 07 MLT in the pre-noon sector and 17 MLT in the post-noon sector, travelling with a velocity of approximately 1.5 to 2 km s-1. These return flow patches have a repetition rate similar to that of the transient features observed at local noon. While providing supporting evidence for the impulsive nature of convection flow, the observation of sunward-propagating features in the return flow region is not consistent with current conceptual models of the excitation of convection.

    Key words. Ionosphere (plasma convection · Magnetospheric physics (magnetopause · cusp · and boundary layers; magnetosphere-ionosphere interactions

  14. The Atlantic Meridional Transect: Spatially Extensive Calibration and Validation of Optical Properties and Remotely Sensed Measurements of Ocean Colour

    Science.gov (United States)

    Aiken, James; Hooker, Stanford

    1997-01-01

    Twice a year, the Royal Research Ship (RRS) James Clark Ross (JCR) steams a meridional transect of the atlantic Ocean between Grimsly (UK) and Stanley (Falkland Islands) with a port call in Montevideo (Uruguay), as part of the annual research activities of the British Antarctic Survey (BAS). In September, the JCR sails from the UK, and the following April it makes the return trip. The ship is operated by the BAS for the Natural Environment Research Council (NERC). The Atlantic Meridional Transect (AMT) Program exploits the passage of the JCR from approximately 50 deg. N to 50 deg. S with a primary objective to investigate physical and biological processes, as well as to measure the mesi-to-basin-scale bio-optical properties of the atlantic Ocean. The calibration and validation of remotely sensed observations of ocean colour is an inherent objective of these studies: first, by relating in situ measurements of water leaving radiance to satellite measurement, and second, by measuring the bio-optically active constituents of the water.

  15. Managing Returnable Containers Logistics - A Case Study Part I - Physical and Information Flow Analysis

    Directory of Open Access Journals (Sweden)

    Reza A. Maleki

    2011-05-01

    Full Text Available This case study paper is the result of a project conducted on behalf of a company, hereon referred to as Midwest Assembly and Manufacturing or MAAN. The company's operations include component manufacturing, painting, and assembling products. The company also purchases a relatively large percentage of components and major assemblies that are needed to support final assembly operations. MAAN uses its own returnable containers to transport purchased parts from suppliers. Due to poor tracking of the containers, the company has been experiencing lost containers and occasional production disruptions at its facility well as at the supplier sites. The objective of this project was to develop a proposal to enable MAAN to more effectively track and manage its returnable containers. The research activities in support of this project included the analysis and documentation of both the physical flow and the information flow associated with the containers as well as some of the technologies that can help with automatic identification and tracking of containers. The focal point of this paper is on a macro?level approach for the analysis of container and information flow within the logistics chain. A companion paper deals with several of the automatic identification technologies that have the potential to improve the management of MAAN's returnable containers.

  16. PENGARUH EARNINGS, OPERATING CASH FLOW DAN ASSET GROWTH TERHADAP STOCK RETURN PERUSAHAAN YANG TERDAFTAR PADA INDEKS LQ 45 UNTUK PERIODE 2009-2011

    Directory of Open Access Journals (Sweden)

    Yulius ,

    2017-02-01

    Full Text Available The objective of this research is to test the impact of earnings, operating cash flow and asset growth to firm’s stock return which listed in LQ 45 index in Indonesian for 2009-2011. The result of this research is earnings, operating cash flow and asset growth have not significant effect to stock return both when those variabels is tested separately or silmutaneously. This result show that earnings, operating cash flow and asset growth are not only the one to be the basis of consideration for investor to make investment to get the stock return. Therefore, for making investment, investor should consider other factors which effect the firm’s stock return as macro economics and politics. Furthermore, from this result, be expected an improvement of quality financial statement which addopted IFRS. Keyword: Earnings, Operating Cash Flow, Asset Growth, Stock Return.

  17. Laboratory Evaluation of Air Flow Measurement Methods for Residential HVAC Returns for New Instrument Standards

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Stratton, Chris [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-08-01

    This project improved the accuracy of air flow measurements used in commissioning California heating and air conditioning systems in Title 24 (Building and Appliance Efficiency Standards), thereby improving system performance and efficiency of California residences. The research team at Lawrence Berkeley National Laboratory addressed the issue that typical tools used by contractors in the field to test air flows may not be accurate enough to measure return flows used in Title 24 applications. The team developed guidance on performance of current diagnostics as well as a draft test method for use in future evaluations. The study team prepared a draft test method through ASTM International to determine the uncertainty of air flow measurements at residential heating ventilation and air conditioning returns and other terminals. This test method, when finalized, can be used by the Energy Commission and other entities to specify required accuracy of measurement devices used to show compliance with standards.

  18. Simulated variability of the Atlantic meridional overturning circulation

    Science.gov (United States)

    Bentsen, M.; Drange, H.; Furevik, T.; Zhou, T.

    To examine the multi-annual to decadal scale variability of the Atlantic Meridional Overturning Circulation (AMOC) we conducted a four-member ensemble with a daily reanalysis forced, medium-resolution global version of the isopycnic coordinate ocean model MICOM, and a 300-years integration with the fully coupled Bergen Climate Model (BCM). The simulations of the AMOC with both model systems yield a long-term mean value of 18 Sv and decadal variability with an amplitude of 1-3 Sv. The power spectrum of the inter-annual to decadal scale variability of the AMOC in BCM generally follows the theoretical red noise spectrum, with indications of increased power near the 20-years period. Comparison with observational proxy indices for the AMOC, e.g. the thickness of the Labrador Sea Water, the strength of the baroclinic gyre circulation in the North Atlantic Ocean, and the surface temperature anomalies along the mean path of the Gulf Stream, shows similar trends and phasing of the variability, indicating that the simulated AMOC variability is robust and real. Mixing indices have been constructed for the Labrador, the Irminger and the Greenland-Iceland-Norwegian (GIN) seas. While convective mixing in the Labrador and the GIN seas are in opposite phase, and linked to the NAO as observations suggest, the convective mixing in the Irminger Sea is in phase with or leads the Labrador Sea. Newly formed deep water is seen as a slow, anomalous cold and fresh, plume flowing southward along the western continental slope of the Atlantic Ocean, with a return flow of warm and saline water on the surface. In addition, fast-travelling topographically trapped waves propagate southward along the continental slope towards equator, where they go east and continue along the eastern rim of the Atlantic. For both types of experiments, the Northern Hemisphere sea level pressure and 2 m temperature anomaly patterns computed based on the difference between climate states with strong and weak AMOC

  19. Simulated responses of streams and ponds to groundwater withdrawals and wastewater return flows in southeastern Massachusetts

    Science.gov (United States)

    Carlson, Carl S.; Walter, Donald A.; Barbaro, Jeffrey R.

    2015-12-21

    Water use, such as withdrawals, wastewater return flows, and interbasin transfers, can alter streamflow regimes, water quality, and the integrity of aquatic habitat and affect the availability of water for human and ecosystem needs. To provide the information needed to determine alteration of streamflows and pond water levels in southeastern Massachusetts, existing groundwater models of the Plymouth-Carver region and western (Sagamore flow lens) and eastern (Monomoy flow lens) Cape Cod were used to delineate subbasins and simulate long-term average and average monthly streamflows and pond levels for a series of water-use conditions. Model simulations were used to determine the extent to which streamflows and pond levels were altered by comparing simulated streamflows and pond levels under predevelopment conditions with streamflows and pond levels under pumping only and pumping with wastewater return flow conditions. The pumping and wastewater return flow rates used in this study are the same as those used in previously published U.S. Geological Survey studies in southeastern Massachusetts and represent the period from 2000 to 2005. Streamflow alteration for the nontidal portions of streams in southeastern Massachusetts was evaluated within and at the downstream outlets of 78 groundwater subbasins delineated for this study. Evaluation of streamflow alteration at subbasin outlets is consistent with the approach used by the U.S. Geological Survey for the topographically derived subbasins in the rest of Massachusetts.

  20. Interannual Variability in the Meridional Transport of Water Vapor

    Science.gov (United States)

    Cohen, Judah L.; Salstein, David A.; Rosen, Richard D.

    2000-01-01

    The zonal-mean meridional transport of water vapor across the globe is evaluated using the National Centers for Environmental Prediction-National Center for Atmospheric Research (NCEP-NCAR) reanalysis for 1948-97. The shape of the meridional profile of the climatological mean transport closely resembles that of previous mean climate descriptions, but values tend to be notably larger than in climatologies derived from radiosonde-only-based analyses. The unprecedented length of the NCEP-NCAR dataset invites a focus on interannual variations in the zonal-mean moisture transport, and these results for northern winter are highlighted here. Although interannual variability in the transport is typically small at most latitudes, a significant ENSO signal is present, marked by a strengthening of water vapor transports over much of the winter hemisphere during warm events. Because of an increase in tropical sea surface temperatures and in the frequency of warm events relative to cold events in the latter half of the 50-yr record, this interannual signal projects onto an overall trend toward enhanced meridional moisture transports in the global hydrological cycle.

  1. Escleroplastia meridional: A propósito de un caso en 1999 Meridional scleroplasty: With regard to a case in 1999

    Directory of Open Access Journals (Sweden)

    Enrique J. Machado Fernández

    2000-06-01

    Full Text Available En este artículo se presenta un caso reciente de rechazo al aloplante utilizado para escleroplastia meridional. Se refieren las características del cuadro clínico presentado y su tratamiento. Además, se expresan consideraciones basadas en datos estadísticos y hallazgos anatomopatológicos que fundamentan la suspensión de la práctica de esta técnica en el Centro de Microcirugía Ocular.In present paper, authors present a recent case of rejection to allograft used to meridional scleroplasty. Festures of clinical picture and its treatment are related. Furthermore, we express statistical data based on considerations and anatomic-pathologic findings supporting suspension of practice of this technique in Center of Microsurgery of Eye.

  2. Currents, Geostrophic, Aviso, 0.25 degrees, Global, Meridional

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Aviso Meridional Geostrophic Current is inferred from Sea Surface Height Deviation, climatological dynamic height, and basic fluid mechanics.

  3. Vortex flow in acoustically levitated drops

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Z.L.; Xie, W.J. [Department of Applied Physics, Northwestern Polytechnical University, Xi' an 710072 (China); Wei, B., E-mail: bbwei@nwpu.edu.cn [Department of Applied Physics, Northwestern Polytechnical University, Xi' an 710072 (China)

    2011-08-29

    The internal flow of acoustically levitated water drops is investigated experimentally. This study reveals a kind of vortex flow which rotates in the meridional plane of the levitated drop. The magnitude of fluid velocity is nearly vanishing at the drop center, whereas it increases toward the free surface of a levitated drop until the maximum value of about 80 mm/s. A transition of streamline shapes from concentric circles to ellipses takes place at the distance of about 1.2 mm from the drop center. The fluid velocity distribution is plotted as a function of polar angle for seven characteristic streamlines. -- Highlights: → We experimentally observe the internal flow of acoustically levitated water drops. → We present a fascinating structure of vortex flow inside the levitated water drop. → This vortex flow rotates around the drop center in the meridional plane. → Velocity distribution information of this vortex flow is quantitatively analyzed.

  4. Vortex flow in acoustically levitated drops

    International Nuclear Information System (INIS)

    Yan, Z.L.; Xie, W.J.; Wei, B.

    2011-01-01

    The internal flow of acoustically levitated water drops is investigated experimentally. This study reveals a kind of vortex flow which rotates in the meridional plane of the levitated drop. The magnitude of fluid velocity is nearly vanishing at the drop center, whereas it increases toward the free surface of a levitated drop until the maximum value of about 80 mm/s. A transition of streamline shapes from concentric circles to ellipses takes place at the distance of about 1.2 mm from the drop center. The fluid velocity distribution is plotted as a function of polar angle for seven characteristic streamlines. -- Highlights: → We experimentally observe the internal flow of acoustically levitated water drops. → We present a fascinating structure of vortex flow inside the levitated water drop. → This vortex flow rotates around the drop center in the meridional plane. → Velocity distribution information of this vortex flow is quantitatively analyzed.

  5. A study on the relationship between operational cash flow and the return of stockholders

    OpenAIRE

    Hassan Ghodrati; Hassan Abyak

    2014-01-01

    Performance measurement in managerial accounting is normally associated with cash flow and it is executed based on different figures such as testing information content abuse and accounting figures. However, increasing the information content in accrual components of earning and internal performance measurement provides additional informative insights. This paper studies the relationship between operating cash flows and earnings along with total shareholder returns. The study chooses the info...

  6. South Atlantic meridional transports from NEMO-based simulations and reanalyses

    Science.gov (United States)

    Mignac, Davi; Ferreira, David; Haines, Keith

    2018-02-01

    The meridional heat transport (MHT) of the South Atlantic plays a key role in the global heat budget: it is the only equatorward basin-scale ocean heat transport and it sets the northward direction of the global cross-equatorial transport. Its strength and variability, however, are not well known. The South Atlantic transports are evaluated for four state-of-the-art global ocean reanalyses (ORAs) and two free-running models (FRMs) in the period 1997-2010. All products employ the Nucleus for European Modelling of the Oceans (NEMO) model, and the ORAs share very similar configurations. Very few previous works have looked at ocean circulation patterns in reanalysis products, but here we show that the ORA basin interior transports are consistently improved by the assimilated in situ and satellite observations relative to the FRMs, especially in the Argo period. The ORAs also exhibit systematically higher meridional transports than the FRMs, which is in closer agreement with observational estimates at 35 and 11° S. However, the data assimilation impact on the meridional transports still greatly varies among the ORAs, leading to differences up to ˜ 8 Sv and 0.4 PW in the South Atlantic Meridional Overturning Circulation and the MHTs, respectively. We narrow this down to large inter-product discrepancies in the western boundary currents (WBCs) at both upper and deep levels explaining up to ˜ 85 % of the inter-product differences in MHT. We show that meridional velocity differences, rather than temperature differences, in the WBCs drive ˜ 83 % of this MHT spread. These findings show that the present ocean observation network and data assimilation schemes can be used to consistently constrain the South Atlantic interior circulation but not the overturning component, which is dominated by the narrow western boundary currents. This will likely limit the effectiveness of ORA products for climate or decadal prediction studies.

  7. Development and evaluation of a meter for measuring return line fluid flow rates during drilling

    Energy Technology Data Exchange (ETDEWEB)

    Loeppke, G.E.; Schafer, D.M.; Glowka, D.A.; Scott, D.D.; Wernig, M.D. (Sandia National Labs., Albuquerque, NM (United States)); Wright, E.K. (Ktech Corp., Albuquerque, NM (United States))

    1992-06-01

    The most costly problem routinely encountered in geothermal drilling is lost circulation, which occurs when drilling fluid is lost to the formation rather than circulating back to the surface. The successful and economical treatment of lost circulation requires the accurate measurement of drilling fluid flow rate both into and out of the well. This report documents the development of a meter for measuring drilling fluid outflow rates in the return line of a drilling rig. The meter employs a rolling counterbalanced float that rides on the surface of the fluid in the return line. The angle of the float pivot arm is sensed with a pendulum potentiometer, and the height of the float is calculated from this measurement. The float height is closely related to the fluid height and, therefore, the flow rate in the line. The prototype rolling float meter was extensively tested under laboratory conditions in the Wellbore Hydraulics Flow Facility; results from these tests were used in the design of the field prototype rolling float meter. The field prototype meter was tested under actual drilling conditions in August and September 1991 at the Long Valley Exploratory Well near Mammoth Lakes, Ca. In addition, the performance of several other commercially available inflow and outflow meters was evaluated in the field. The tested inflow meters included conventional pump stroke counters, rotary pump speed counters, magnetic flowmeters, and an ultrasonic Doppler flowmeter. On the return flow line, a standard paddlemeter, an acoustic level meter, and the prototype rolling float meter were evaluated for measuring drilling fluid outflow rates.

  8. The impact of irrigation return flow on aspects of the water quality of ...

    African Journals Online (AJOL)

    Groundwater quality in the Loerie Flats, and subsurface irrigation return flow to the upper Gamtoos estuary was monitored from November 1992 to April 1994. The nutrient loading of groundwater was highly variable both spatially and temporally, with elevated nitrate-N levels reaching 163 mg·l -1 . The elevated nutrient ...

  9. Effect of irrigation return flow on groundwater recharge in an overexploited aquifer in Bangladesh

    Science.gov (United States)

    Touhidul Mustafa, Syed Md.; Shamsudduha, Mohammad; Huysmans, Marijke

    2016-04-01

    Irrigated agriculture has an important role in the food production to ensure food security of Bangladesh that is home to over 150 million people. However, overexploitation of groundwater for irrigation, particularly during the dry season, causes groundwater-level decline in areas where abstraction is high and surface geology inhibits direct recharge to underlying shallow aquifer. This is causing a number of potential adverse socio-economic, hydrogeological, and environmental problems in Bangladesh. Alluvial aquifers are primarily recharged during monsoon season from rainfall and surface sources. However, return flow from groundwater-fed irrigation can recharge during the dry months. Quantification of the effect of return flow from irrigation in the groundwater system is currently unclear but thought to be important to ensure sustainable management of the overexploited aquifer. The objective of the study is to investigate the effect of irrigation return flow on groundwater recharge in the north-western part of Bangladesh, also known as Barind Tract. A semi-physically based distributed water balance model (WetSpass-M) is used to simulate spatially distributed monthly groundwater recharge. Results show that, groundwater abstraction for irrigation in the study area has increased steadily over the last 29 years. During the monsoon season, local precipitation is the controlling factor of groundwater recharge; however, there is no trend in groundwater recharge during that period. During the dry season, however, irrigation return-flow plays a major role in recharging the aquifer in the irrigated area compared to local precipitation. Therefore, during the dry season, mean seasonal groundwater recharge has increased and almost doubled over the last 29 years as a result of increased abstraction for irrigation. The increase in groundwater recharge during dry season has however no significant effect in the improvement of groundwater levels. The relation between groundwater

  10. Speciation and fate of copper in sewage treatment works with and without tertiary treatment: the effect of return flows.

    Science.gov (United States)

    Innaa, D; Lester, J N; Scrimshawb, M D; Cartmell, E

    2014-01-01

    The removal of metals from wastewaters is becoming an important issue, with new environmental quality standards putting increased regulatory pressure on operators of sewage treatment works. The use of additional processes (tertiary treatment) following two-stage biological treatment is frequently seen as a way of improving effluent quality for nutrients and suspended solids, and this study investigates the impact of how back washes from these tertiary processes may impact the removal of copper during primary sedimentation. Seven sites were studied, three conventional two-stage biological treatment, and four with tertiary processes. It was apparent that fluxes of copper in traditional return flows made a significant contribution to the load to the primary treatment tanks, and that tanks. These return flows had an impact on copper removal in the primary tanks, probably due to their aerobic nature. Returning such aerobic back wash flows to the main process stream after primary treatment may therefore be worth consideration. The opportunity to treat consolidated liquor and sludge.flows in side-stream processes to remove toxic elements, as they are relatively concentrated, low volume flow streams, should also be evaluated.

  11. Return Persistence and Fund Flows in the Worst Performing Mutual Funds

    OpenAIRE

    Jonathan B. Berk; Ian Tonks

    2007-01-01

    We document that the observed persistence amongst the worst performing actively managed mutual funds is attributable to funds that have performed poorly both in the current and prior year. We demonstrate that this persistence results from an unwillingness of investors in these funds to respond to bad performance by withdrawing their capital. In contrast, funds that only performed poorly in the current year have a significantly larger (out)flow of funds/return sensitivity and consequently show...

  12. Simulation of the Effects of Water Withdrawals, Wastewater Return Flows, and Land-Use Change on Streamflow in the Blackstone River Basin, Massachusetts and Rhode Island

    Science.gov (United States)

    Barbaro, Jeffrey R.

    2007-01-01

    Streamflow in many parts of the Blackstone River Basin in south-central Massachusetts and northern Rhode Island is altered by water-supply withdrawals, wastewater-return flows, and land-use change associated with a growing population. Simulations from a previously developed and calibrated Hydrological Simulation Program?FORTRAN (HSPF) precipitation-runoff model for the basin were used to evaluate the effects of water withdrawals, wastewater-return flows, and land-use change on streamflow. Most of the simulations were done for recent (1996?2001) conditions and potential buildout conditions in the future when all available land is developed to provide a long-range assessment of the effects of possible future human activities on water resources in the basin. The effects of land-use change were evaluated by comparing the results of long-term (1960?2004) simulations with (1) undeveloped land use, (2) 1995?1999 land use, and (3) potential buildout land use at selected sites across the basin. Flow-duration curves for these land-use scenarios were similar, indicating that land-use change, as represented in the HSPF model, had little effect on flow in the major tributary streams and rivers in the basin. However, land-use change?particularly increased effective impervious area?could potentially have greater effects on the hydrology, water quality, and aquatic habitat of the smaller streams in the basin. The effects of water withdrawals and wastewater-return flows were evaluated by comparing the results of long-term simulations with (1) no withdrawals and return flows, (2) actual (measured) 1996?2001 withdrawals and wastewater-return flows, and (3) potential withdrawals and wastewater-return flows at buildout. Overall, the results indicated that water use had a much larger effect on streamflow than did land use, and that the location and magnitude of wastewater-return flows were important for lessening the effects of withdrawals on streamflow in the Blackstone River Basin

  13. Return to axi-symmetry for pipe flows generated after a fractal orifice

    Energy Technology Data Exchange (ETDEWEB)

    Nicolleau, F C G A, E-mail: F.Nicolleau@Sheffield.ac.uk [SFMG, Department of Mechanical Engineering, University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom)

    2013-12-15

    We present experimental results obtained from pipe flows generated by fractal shaped orifices or openings. We compare different fractal orifices and their efficiencies to re-generate axi-symmetric flows and to return to the standard flow generated by a perforated plate or a circular orifice plate. We consider two families of fractal openings: mono-orifice and complex orifice and emphasize the differences between the two fractal families. For the Reynolds number we used, we found that there is an optimum iteration for the fractal level above which no improvement for practical applications such as flowmetering is to be expected. The main parameters we propose for the characterization of the fractal orifice are the connexity parameter, the symmetry angle and the gap to the wall {delta}*{sub g}. The results presented here are among the first for flows forced through fractal openings and will serve as a reference for future studies and benchmarks for numerical applications. (paper)

  14. Return to axi-symmetry for pipe flows generated after a fractal orifice

    International Nuclear Information System (INIS)

    Nicolleau, F C G A

    2013-01-01

    We present experimental results obtained from pipe flows generated by fractal shaped orifices or openings. We compare different fractal orifices and their efficiencies to re-generate axi-symmetric flows and to return to the standard flow generated by a perforated plate or a circular orifice plate. We consider two families of fractal openings: mono-orifice and complex orifice and emphasize the differences between the two fractal families. For the Reynolds number we used, we found that there is an optimum iteration for the fractal level above which no improvement for practical applications such as flowmetering is to be expected. The main parameters we propose for the characterization of the fractal orifice are the connexity parameter, the symmetry angle and the gap to the wall δ* g . The results presented here are among the first for flows forced through fractal openings and will serve as a reference for future studies and benchmarks for numerical applications. (paper)

  15. Numerical Study of Flow Motion and Patterns Driven by a Rotating Permanent Helical Magnetic Field

    Science.gov (United States)

    Yang, Wenzhi; Wang, Xiaodong; Wang, Bo; Baltaretu, Florin; Etay, Jacqueline; Fautrelle, Yves

    2016-10-01

    Liquid metal magnetohydrodynamic flow driven by a rotating permanent helical magnetic field in a cylindrical container is numerically studied. A three-dimensional numerical simulation provides insight into the visualization of the physical fields, including the magnetic field, the Lorentz force density, and the flow structures, especially the flow patterns in the meridional plane. Because the screen parameter is sufficiently small, the model is decoupled into electromagnetic and hydrodynamic components. Two flow patterns in the meridional plane, i.e., the global flow and the secondary flow, are discovered and the impact of several system parameters on their transition is investigated. Finally, a verifying model is used for comparison with the previous experiment.

  16. THE MEAN-FIELD SOLAR DYNAMO WITH A DOUBLE CELL MERIDIONAL CIRCULATION PATTERN

    Energy Technology Data Exchange (ETDEWEB)

    Pipin, V. V. [Institute of Solar-Terrestrial Physics, Russian Academy of Sciences, Irkutsk, 664033 (Russian Federation); Kosovichev, A. G. [Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305 (United States)

    2013-10-10

    Recent helioseismology findings, as well as advances in direct numerical simulations of global dynamics of the Sun, have indicated that in each solar hemisphere meridional circulation may form more than one cell along the radius in the convection zone. In particular, recent helioseismology results revealed a double-cell structure of the meridional circulation. We investigate properties of a mean-field solar dynamo with such double-cell meridional circulation. The dynamo model also includes the realistic profile of solar differential rotation (including the tachocline and subsurface shear layer) and takes into account effects of turbulent pumping, anisotropic turbulent diffusivity, and conservation of magnetic helicity. Contrary to previous flux-transport dynamo models, we find that the dynamo model can robustly reproduce the basic properties of the solar magnetic cycles for a wide range of model parameters and circulation speeds. The best agreement with observations is achieved when the surface meridional circulation speed is about 12 m s{sup –1}. For this circulation speed, the simulated sunspot activity shows good synchronization with the polar magnetic fields. Such synchronization was indeed observed during previous sunspot Cycles 21 and 22. We compare theoretical and observed phase diagrams of the sunspot number and the polar field strength and discuss the peculiar properties of Cycle 23.

  17. Role of asymmetric meridional circulation in producing north-south asymmetry in a solar cycle dynamo model

    Energy Technology Data Exchange (ETDEWEB)

    Belucz, Bernadett [Eötvös University, Department of Astronomy, 1518 Budapest, Pf. 32 (Hungary); Dikpati, Mausumi [High Altitude Observatory, National Center for Atmospheric Research, 3080 Center Green, Boulder, CO 80307-3000 (United States)

    2013-12-10

    Solar cycles in the north and south hemispheres differ in cycle length, amplitude, profile, polar fields, and coronal structure. To show what role differences in meridional flow could play in producing these differences, we present the results of three sets of numerical simulations from a flux transport dynamo in which one property of meridional circulation has been changed in the south only. The changes are in amplitude and the presence of a second cell in latitude or in depth. An ascending phase speedup causes weakening of polar and toroidal fields; a speed decrease in a late descending phase does not change amplitudes. A long-duration speed increase leads to lower toroidal field peaks but unchanged polar field peaks. A second high-latitude circulation cell in an ascending phase weakens the next polar and toroidal field peaks, and the ascending phase is lengthened. A second cell in a late descending phase speeds up the cycle. A long-duration second cell leads to a poleward branch of the butterfly diagram and weaker polar fields. A second cell in depth reverses the tilt of the butterfly wing, decreasing polar fields when added during an ascending phase and increasing them during a late descending phase. A long-duration presence of a second cell in radius evolves the butterfly diagram far away from the observed one, with different dynamo periods in low and high latitudes. Thus, a second cell in depth is unlikely to persist more than a few years if the solar dynamo is advection-dominated. Our results show the importance of time variation and north-south asymmetry in meridional circulation in producing differing cycles in the north and south.

  18. Role of asymmetric meridional circulation in producing north-south asymmetry in a solar cycle dynamo model

    International Nuclear Information System (INIS)

    Belucz, Bernadett; Dikpati, Mausumi

    2013-01-01

    Solar cycles in the north and south hemispheres differ in cycle length, amplitude, profile, polar fields, and coronal structure. To show what role differences in meridional flow could play in producing these differences, we present the results of three sets of numerical simulations from a flux transport dynamo in which one property of meridional circulation has been changed in the south only. The changes are in amplitude and the presence of a second cell in latitude or in depth. An ascending phase speedup causes weakening of polar and toroidal fields; a speed decrease in a late descending phase does not change amplitudes. A long-duration speed increase leads to lower toroidal field peaks but unchanged polar field peaks. A second high-latitude circulation cell in an ascending phase weakens the next polar and toroidal field peaks, and the ascending phase is lengthened. A second cell in a late descending phase speeds up the cycle. A long-duration second cell leads to a poleward branch of the butterfly diagram and weaker polar fields. A second cell in depth reverses the tilt of the butterfly wing, decreasing polar fields when added during an ascending phase and increasing them during a late descending phase. A long-duration presence of a second cell in radius evolves the butterfly diagram far away from the observed one, with different dynamo periods in low and high latitudes. Thus, a second cell in depth is unlikely to persist more than a few years if the solar dynamo is advection-dominated. Our results show the importance of time variation and north-south asymmetry in meridional circulation in producing differing cycles in the north and south.

  19. River water quality management considering agricultural return flows: application of a nonlinear two-stage stochastic fuzzy programming.

    Science.gov (United States)

    Tavakoli, Ali; Nikoo, Mohammad Reza; Kerachian, Reza; Soltani, Maryam

    2015-04-01

    In this paper, a new fuzzy methodology is developed to optimize water and waste load allocation (WWLA) in rivers under uncertainty. An interactive two-stage stochastic fuzzy programming (ITSFP) method is utilized to handle parameter uncertainties, which are expressed as fuzzy boundary intervals. An iterative linear programming (ILP) is also used for solving the nonlinear optimization model. To accurately consider the impacts of the water and waste load allocation strategies on the river water quality, a calibrated QUAL2Kw model is linked with the WWLA optimization model. The soil, water, atmosphere, and plant (SWAP) simulation model is utilized to determine the quantity and quality of each agricultural return flow. To control pollution loads of agricultural networks, it is assumed that a part of each agricultural return flow can be diverted to an evaporation pond and also another part of it can be stored in a detention pond. In detention ponds, contaminated water is exposed to solar radiation for disinfecting pathogens. Results of applying the proposed methodology to the Dez River system in the southwestern region of Iran illustrate its effectiveness and applicability for water and waste load allocation in rivers. In the planning phase, this methodology can be used for estimating the capacities of return flow diversion system and evaporation and detention ponds.

  20. Asymmetric vibrations of shells of revolution having meridionally varying curvature and thickness

    International Nuclear Information System (INIS)

    Suzuki, Katsuyoshi; Kosawada, Tadashi; Miura, Kazuyuki.

    1988-01-01

    An exact method using power series expansions is presented for solving asymmetric free vibration problems for shells of revolution having meridionally varying curvature and thickness. The gaverning equations of motion and the boundary conditions are derived from the stationary conditions of the Lagrangian of the shells of revolution. The method is demonstrated for shells of revolution having elliptical, cycloidal, parabolical, catenary and hyperbolical meridional curvature. The natural frequencies are numerically calculated for these shells having second degree thickness variation. (author)

  1. Interconverting the matrix and principal-meridional representations of dioptric power and reduced vergence.

    Science.gov (United States)

    Harris, W F

    2000-11-01

    Converting the traditional representation of power as sphere, cylinder and axis to the dioptric power matrix F is usually performed by means of Long's equations and the reverse process by means of Keating's equations. It is sometimes useful to be able to convert directly between the matrix and power expressed in terms of principal powers F1 and F2 along corresponding principal meridians at angles a1 and a2. The equations for interconverting F and the principal-meridional representation expressed as F1(a1)F2 are presented here. Equivalent equations allow direct interconversion of the reduced vergence matrix L and the principal-meridional representation of vergence L1(a1)L2. Vergence becomes infinite at line and point focuses. Similarly effective power and back- and front-vertex power are infinite for some systems. Nevertheless it is possible unambiguously to represent infinite vergence and vertex power in principal-meridional form. However, information is usually lost in these infinite cases when the principal-meridional representation is converted to the matrix representation, and the former is not recoverable from the latter. As a consequence the matrix representation is usually unsatisfactory for vergences and vertex powers that are infinite. On the other hand, the principal-meridional representation of vergence and power is always satisfactory. If one adopts the position that effective powers and vertex powers are really vergences rather than powers then one concludes that the matrix provides a satisfactory representation for powers of thin systems in general but not for vergences. Implied by a vergence at a point is an interval of Sturm. The equations for characterizing the interval from the reduced vergence are presented.

  2. Bifurcations of a creeping air–water flow in a conical container

    DEFF Research Database (Denmark)

    Balci, Adnan; Brøns, Morten; Herrada, Miguel A.

    2016-01-01

    . They are investigated for (Formula presented.), and (Formula presented.). For small (Formula presented.), the air flow is multi-cellular with clockwise meridional circulation near the disk. The air flow becomes one cellular as (Formula presented.) exceeds a threshold depending on (Formula presented.). For all (Formula...... presented.), the water flow has an unbounded number of eddies whose size and strength diminish as the cone apex is approached. As the water level becomes close to the disk, the outmost water eddy with clockwise meridional circulation expands, reaches the interface, and induces a thin layer...... with anticlockwise circulation in the air. Then this layer expands and occupies the entire air domain. The physical reasons for the flow transformations are provided. The results are of fundamental interest and can be relevant for aerial bioreactors....

  3. MENTAT: A New Magnetic Meridional Neutral Wind Model for Earth's Thermosphere

    Science.gov (United States)

    Dandenault, P. B.

    2017-12-01

    We present a new model of thermosphere winds in the F region obtained from variations in the altitude of the peak density of the ionosphere (hmF2). The new Magnetic mEridional NeuTrAl Thermospheric (MENTAT) wind model produces magnetic-meridional neutral winds as a function of year, day of year, solar local time, solar flux, geographic latitude, and geographic longitude. The winds compare well with Fabry-Pérot Interferometer (FPI) wind observations and are shown to provide accurate specifications in regions outside of the observational database such as the midnight collapse of hmF2 at Arecibo, Puerto Rico. The model winds are shown to exhibit the expected seasonal, diurnal, and hourly behavior based on geophysical conditions. The magnetic meridional winds are similar to those from the well-known HWM14 model but there are important differences. For example, Townsville, Australia has a strong midnight collapse similar to that at Arecibo, but winds from HWM14 do not reproduce it. Also, the winds from hmF2 exhibit a moderate solar cycle dependence under certain conditions, whereas, HWM14 has no solar activity dependence. For more information, please visit http://www.mentatwinds.net/.

  4. Asymmetric vibrations of thick shells of revolution having meridionally varying curvature

    International Nuclear Information System (INIS)

    Suzuki, Katsuyoshi; Kosawada, Tadashi; Yachita, Takumi.

    1988-01-01

    An exact method using power series expansions is presented for solving asymmetric free vibration problems for thick shells of revolution having meridionally varying curvature. Based on the improved thick shell theory, the Lagrangian of the shells of revolution are obtained, and the equations of motion and the boundary conditions are derived from the stationary condition of the Lagrangian. The method is demonstrated for thick shells of revolution having elliptical, cycloidal, parabolical, catenary and hyperbolical meridional curvature. The results by the present method are compared with those by the thin shell theory and the effects of the rotatory inertia and the shear deformation upon the natural frequencies are clarified. (author)

  5. Estimated water withdrawals and return flows in Vermont in 2005 and 2020

    Science.gov (United States)

    Medalie, Laura; Horn, Marilee A.

    2010-01-01

    In 2005, about 12 percent of total water withdrawals (440 million gallons per day (Mgal/d)) in Vermont were from groundwater sources (51 Mgal/d), and about 88 percent were from surface-water sources (389 Mgal/d). Of total water withdrawals, about 78 percent were used for cooling at a power plant, 9 percent were withdrawn by public suppliers, about 5 percent were withdrawn for domestic use, about 3 percent were withdrawn for use at fish hatcheries, and the remaining 5 percent were divided among commercial/industrial, irrigation, livestock, and snowmaking uses. About 49 percent of the population of Vermont was supplied with drinking water by a public supplier, and 51 percent was self supplied. Some of the Minor Civil Divisions (MCDs) that had large self-supplied populations were located near the major cities of St. Albans, Burlington, Montpelier, Barre, and Rutland, where the cities themselves were served largely by public supply, but the surrounding areas were not. Most MCDs where withdrawals by community water systems totaled more than 1 Mgal/d used predominantly surface water, and those where withdrawals by community water systems totaled 1 Mgal/d or less used predominantly groundwater. Withdrawals of groundwater greater than 1 Mgal/d were made in Middlebury, Bethel, Hartford, Springfield, and Bennington, and withdrawals of surface water greater than 2 Mgal/d were made in Grand Isle, Burlington, South Burlington, Mendon, Brattleboro, and Vernon. Increases in groundwater withdrawals greater than 0.1 Mgal/d are projected for 2020 for Fairfax, Hardwick, Middlebury, Sharon, Proctor, Springfield, and Manchester. The largest projected increases in surface-water withdrawals from 2005 to 2020 are located along the center axis of the Green Mountains in the ski-area towns of Stowe, Warren, Mendon, Killington, and Wilmington. In 2005, withdrawals were at least 1 Mgal/d greater than return flows in South Burlington, Waterford, Orange, Mendon, Woodford, and Vernon. Many of

  6. Los testimonios de Marte en la Meseta Meridional

    Directory of Open Access Journals (Sweden)

    Julián Hurtado Aguña

    2001-01-01

    Full Text Available Marte, fue una de las más importantes divinidades romanas presentes en Híspanla. Dentro de la Meseta meridional sus testimonios aparecen en algunas localidades de la provincia de Madrid, como Alcalá de Henares, Talamanca del Jarama o Collado Villalba, estando ausentes en otras partes de esta región. Especialmente importante es la presencia de inscripciones dedicadas a Marte en la ciudad romana de Complutum (Alcalá de Henares, donde sus dedicantes pudieran pertenecer en algún caso al grupo social de los libertos.One oí the most important román divinities in Híspanla was Mars. His testimonies in the Meridional Plateau are in some villages of Madrid's province, as Alcalá de Henares, Talamanca del Jarama or Collado Villalba, and they are not in other places of this reglan. Specially important is ttie presence of inscriptions to Mars in ttie román town of Complutum (Alcalá de Henares, wtiere his devotes could belong to the social freedmans group.

  7. Three-pattern decomposition of global atmospheric circulation: part II—dynamical equations of horizontal, meridional and zonal circulations

    Science.gov (United States)

    Hu, Shujuan; Cheng, Jianbo; Xu, Ming; Chou, Jifan

    2018-04-01

    The three-pattern decomposition of global atmospheric circulation (TPDGAC) partitions three-dimensional (3D) atmospheric circulation into horizontal, meridional and zonal components to study the 3D structures of global atmospheric circulation. This paper incorporates the three-pattern decomposition model (TPDM) into primitive equations of atmospheric dynamics and establishes a new set of dynamical equations of the horizontal, meridional and zonal circulations in which the operator properties are studied and energy conservation laws are preserved, as in the primitive equations. The physical significance of the newly established equations is demonstrated. Our findings reveal that the new equations are essentially the 3D vorticity equations of atmosphere and that the time evolution rules of the horizontal, meridional and zonal circulations can be described from the perspective of 3D vorticity evolution. The new set of dynamical equations includes decomposed expressions that can be used to explore the source terms of large-scale atmospheric circulation variations. A simplified model is presented to demonstrate the potential applications of the new equations for studying the dynamics of the Rossby, Hadley and Walker circulations. The model shows that the horizontal air temperature anomaly gradient (ATAG) induces changes in meridional and zonal circulations and promotes the baroclinic evolution of the horizontal circulation. The simplified model also indicates that the absolute vorticity of the horizontal circulation is not conserved, and its changes can be described by changes in the vertical vorticities of the meridional and zonal circulations. Moreover, the thermodynamic equation shows that the induced meridional and zonal circulations and advection transport by the horizontal circulation in turn cause a redistribution of the air temperature. The simplified model reveals the fundamental rules between the evolution of the air temperature and the horizontal, meridional

  8. Currents, HF Radio-derived, Ano Nuevo, Normal Model, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements, with missing values filled in by a normal...

  9. Currents, HF Radio-derived, Monterey Bay, Normal Model, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements, with missing values filled in by a normal...

  10. Currents, HF Radio-derived, SF Bay, 33 hr, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 33 hour running average of the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN...

  11. Currents, HF Radio-derived, SF Bay, 1 hr, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 1 hour average of the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN EXPERIMENTAL...

  12. Atlantic Meridional Overturning Circulation During the Last Glacial Maximum.

    NARCIS (Netherlands)

    Lynch-Stieglitz, J.; Adkins, J.F.; Curry, W.B.; Dokken, T.; Hall, I.R.; Herguera, J.C.; Hirschi, J.J.-M.; Ivanova, E.V.; Kissel, C.; Marchal, O.; Marchitto, T.M.; McCave, I.N.; McManus, J.F.; Mulitza, S.; Ninnemann, U.; Peeters, F.J.C.; Yu, E.-F.; Zahn, R.

    2007-01-01

    The circulation of the deep Atlantic Ocean during the height of the last ice age appears to have been quite different from today. We review observations implying that Atlantic meridional overturning circulation during the Last Glacial Maximum was neither extremely sluggish nor an enhanced version of

  13. Preliminary results of U/Pb geochronology in Meridional Espinhaco Mountain

    International Nuclear Information System (INIS)

    Machado, N.; Schrank, A.; Abreu, F.R. de; Knauer, L.G.; Abreu, P.A.A.

    1989-01-01

    Some samples of the constituent unities from Meridional Espinhaco Mountain for geochronology determining by U/Pb method are presented. The analytical techniques described by Krogh and the Davis linear regression program are used for treating these samples. (author)

  14. Foreign currency returns and systematic risks

    NARCIS (Netherlands)

    Galsband, V.; Nitschka, T.

    2015-01-01

    We apply an empirical approximation of the intertemporal capital asset pricing model (ICAPM) to show that cross-sectional dispersion in currency returns can be rationalized by differences in currency excess returns' sensitivities to the market return's cash-flow news component. This finding echoes

  15. Active Pacific meridional overturning circulation (PMOC) during the warm Pliocene.

    Science.gov (United States)

    Burls, Natalie J; Fedorov, Alexey V; Sigman, Daniel M; Jaccard, Samuel L; Tiedemann, Ralf; Haug, Gerald H

    2017-09-01

    An essential element of modern ocean circulation and climate is the Atlantic meridional overturning circulation (AMOC), which includes deep-water formation in the subarctic North Atlantic. However, a comparable overturning circulation is absent in the Pacific, the world's largest ocean, where relatively fresh surface waters inhibit North Pacific deep convection. We present complementary measurement and modeling evidence that the warm, ~400-ppmv (parts per million by volume) CO 2 world of the Pliocene supported subarctic North Pacific deep-water formation and a Pacific meridional overturning circulation (PMOC) cell. In Pliocene subarctic North Pacific sediments, we report orbitally paced maxima in calcium carbonate accumulation rate, with accompanying pigment and total organic carbon measurements supporting deep-ocean ventilation-driven preservation as their cause. Together with high accumulation rates of biogenic opal, these findings require vigorous bidirectional communication between surface waters and interior waters down to ~3 km in the western subarctic North Pacific, implying deep convection. Redox-sensitive trace metal data provide further evidence of higher Pliocene deep-ocean ventilation before the 2.73-Ma (million years) transition. This observational analysis is supported by climate modeling results, demonstrating that atmospheric moisture transport changes, in response to the reduced meridional sea surface temperature gradients of the Pliocene, were capable of eroding the halocline, leading to deep-water formation in the western subarctic Pacific and a strong PMOC. This second Northern Hemisphere overturning cell has important implications for heat transport, the ocean/atmosphere cycle of carbon, and potentially the equilibrium response of the Pacific to global warming.

  16. Fundamental volatility and stock returns : does fundamental volatility explain stock returns?

    OpenAIRE

    Selboe, Guner K.; Virdee, Jaspal Singh

    2017-01-01

    In this thesis, we investigate whether the fundamental uncertainty can explain the crosssection of stock returns. To measure the fundamental uncertainty, we estimate rolling standard deviations and accounting betas of four different fundamentals: revenues, gross profit, earnings and cash flows. The standard deviation and the beta of revenues significantly explain returns in the Fama-Macbeth procedure, but only appears significant among smaller stocks in the portfolio formation ...

  17. Currents, HF Radio-derived, SF Bay Outlet, 1 hr, Meridional, EXPERIMENTAL

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data is the 1 hour average of the meridional component of ocean surface currents derived from High Frequency Radio-derived measurements. THIS IS AN EXPERIMENTAL...

  18. Meridional transport of salt in the global ocean from an eddy-resolving model

    Science.gov (United States)

    Treguier, A. M.; Deshayes, J.; Le Sommer, J.; Lique, C.; Madec, G.; Penduff, T.; Molines, J.-M.; Barnier, B.; Bourdalle-Badie, R.; Talandier, C.

    2014-04-01

    The meridional transport of salt is computed in a global eddy-resolving numerical model (1/12° resolution) in order to improve our understanding of the ocean salinity budget. A methodology is proposed that allows a global analysis of the salinity balance in relation to surface water fluxes, without defining a "freshwater anomaly" based on an arbitrary reference salinity. The method consists of a decomposition of the meridional transport into (i) the transport by the time-longitude-depth mean velocity, (ii) time-mean velocity recirculations and (iii) transient eddy perturbations. Water is added (rainfall and rivers) or removed (evaporation) at the ocean surface at different latitudes, which creates convergences and divergences of mass transport with maximum and minimum values close to ±1 Sv. The resulting meridional velocity effects a net transport of salt at each latitude (±30 Sv PSU), which is balanced by the time-mean recirculations and by the net effect of eddy salinity-velocity correlations. This balance ensures that the total meridional transport of salt is close to zero, a necessary condition for maintaining a quasi-stationary salinity distribution. Our model confirms that the eddy salt transport cannot be neglected: it is comparable to the transport by the time-mean recirculation (up to 15 Sv PSU) at the poleward and equatorial boundaries of the subtropical gyres. Two different mechanisms are found: eddy contributions are localized in intense currents such as the Kuroshio at the poleward boundary of the subtropical gyres, while they are distributed across the basins at the equatorward boundaries. Closer to the Equator, salinity-velocity correlations are mainly due to the seasonal cycle and large-scale perturbations such as tropical instability waves.

  19. Interannual Variability of the Meridional Width of the Baiu Rainband in June and the Associated Large-Scale Atmospheric Circulations

    Science.gov (United States)

    Tsuji, K.; Tomita, T.

    2016-12-01

    Baiu front, which is defined as a boundary between tropical and polar air masses in the East Asia-western North Pacific sector in boreal early summer, slowly migrates northward with the daily meridional swings. Thus, the interannual variability of meridional width of the baiu rainband reflects the slow northward migration and the daily meridional swings of the baiu front. This study focuses on the meridional width of baiu rainband only in June when the baiu front extends on Japan, and investigates how the width is related to the rainfall of Japan with discussions of associated anomalous large-scale atmospheric circulations. The meridional width of baiu rainband is defined based on the monthly-mean precipitation rate of June, whose threshold is 5mm day-1 that is averaged in 130°-150°E. There is a significant positive correlation between the variations of southern and northern edges of the baiu rainband in June. However, the interannual variance of the southern edge is almost twice larger than that of the northern one. That is, the interannual variability of the meridional width is chiefly caused by the variations of southern edge, and the contribution of northern ones is small. When the meridonal width is narrow (wide), an anomalous anticyclonic (cyclonic) circulation appears to the south of Japan, and the precipitation rate increases (decreases) in the western part of Japan while decreases (increases) in the counterpart. In other words, a local dipole with a node at 140°E appears around Japan in the baiu rainfall anomalies. The anomalous anticyclonic (cyclonic) circulation to the south of Japan, which controls the interannual variability of meridional width of the baiu rainband, is induced by the strength of Indian summer monsoon. When the convective activity of Indian summer monsoon is strong (week), the Tibetan high in the upper troposphere extends more (less) eastward. The induced stronger (weaker) descent leads stronger (weaker) Bonin high in the western

  20. Interaction of impeller and guide vane in a series-designed axial-flow pump

    International Nuclear Information System (INIS)

    Kim, S; Choi, Y S; Lee, K Y; Kim, J H

    2012-01-01

    In this paper, the interaction of the impeller and guide vane in a series-designed axial-flow pump was examined through the implementation of a commercial CFD code. The impeller series design refers to the general design procedure of the base impeller shape which must satisfy the various flow rate and head requirements by changing the impeller setting angle and number of blades of the base impeller. An arc type meridional shape was used to keep the meridional shape of the hub and shroud with various impeller setting angles. The blade angle and the thickness distribution of the impeller were designed as an NACA airfoil type. In the design of the guide vane, it was necessary to consider the outlet flow condition of the impeller with the given setting angle. The meridional shape of the guide vane were designed taking into consideration the setting angle of the impeller, and the blade angle distribution of the guide vane was determined with a traditional design method using vane plane development. In order to achieve the optimum impeller design and guide vane, three-dimensional computational fluid dynamics and the DOE method were applied. The interaction between the impeller and guide vane with different combination set of impeller setting angles and number of impeller blades was addressed by analyzing the flow field of the computational results.

  1. Causes and impacts of changes in the stratospheric meridional circulation in a chemistry-climate model

    Energy Technology Data Exchange (ETDEWEB)

    Garny, Hella

    2011-05-13

    The stratospheric meridional circulation is projected to be subject to changes due to enhanced greenhouse-gas concentrations in the atmosphere. This study aims to diagnose and explain long-term changes in the stratospheric meridional circulation using the chemistry-climate model E39CA. The diagnosed strengthening of the circulation is found to be driven by increases in tropical sea surface temperatures which lead to a strengthening and upward shift of the subtropical jets. This enables enhanced vertical propagation of large scale waves into the lower stratosphere, and therefore stronger local wave forcing of the meridional circulation in the tropical lower stratosphere. The impact of changes in transport on the ozone layer is analysed using a newly developed method that allows the separation of the effects of transport and chemistry changes on ozone. It is found that future changes of mean stratospheric ozone concentrations are largely determined by changes in chemistry, while changes in transport of ozone play a minor role. (orig.)

  2. Wind Stress, METOP ASCAT, 0.25 degrees, Global, Near Real Time, Meridional

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes near real time wind stress data in zonal, meridional, modulus, and wind stress curl sets. This data begins with wind velocity...

  3. Computing return times or return periods with rare event algorithms

    Science.gov (United States)

    Lestang, Thibault; Ragone, Francesco; Bréhier, Charles-Edouard; Herbert, Corentin; Bouchet, Freddy

    2018-04-01

    The average time between two occurrences of the same event, referred to as its return time (or return period), is a useful statistical concept for practical applications. For instance insurances or public agencies may be interested by the return time of a 10 m flood of the Seine river in Paris. However, due to their scarcity, reliably estimating return times for rare events is very difficult using either observational data or direct numerical simulations. For rare events, an estimator for return times can be built from the extrema of the observable on trajectory blocks. Here, we show that this estimator can be improved to remain accurate for return times of the order of the block size. More importantly, we show that this approach can be generalised to estimate return times from numerical algorithms specifically designed to sample rare events. So far those algorithms often compute probabilities, rather than return times. The approach we propose provides a computationally extremely efficient way to estimate numerically the return times of rare events for a dynamical system, gaining several orders of magnitude of computational costs. We illustrate the method on two kinds of observables, instantaneous and time-averaged, using two different rare event algorithms, for a simple stochastic process, the Ornstein–Uhlenbeck process. As an example of realistic applications to complex systems, we finally discuss extreme values of the drag on an object in a turbulent flow.

  4. Wind Stress, QuikSCAT SeaWinds, 0.25 degrees, Global, Science Quality, Meridional

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes science quality wind stress data in zonal, meridional, modulus, and wind stress curl sets. This data begins with wind velocity...

  5. Interhemispheric teleconnections: Late Pliocene change in Mediterranean outflow water linked to changes in Indonesian Through-Flow and Atlantic Meridional Overturning Circulation, a review and update

    Science.gov (United States)

    Sarnthein, Michael; Grunert, Patrick; Khélifi, Nabil; Frank, Martin; Nürnberg, Dirk

    2018-03-01

    The ultimate, possibly geodynamic control and potential impact of changes in circulation activity and salt discharge of Mediterranean outflow waters (MOW) on Atlantic meridional overturning circulation have formed long-standing objectives in paleoceanography. Late Pliocene changes in the distal advection of MOW were reconstructed on orbital timescales for northeast Atlantic DSDP/ODP sites 548 and 982 off Brittany and on Rockall Plateau, supplemented by a proximal record from Site U1389 west off Gibraltar, and compared to Western Mediterranean surface and deep-water records of Alboran Sea Site 978. From 3.43 to 3.3 Ma, MOW temperatures and salinities form a prominent rise by 2-4 °C and 3 psu, induced by a preceding and coeval rise in sea surface and deep-water salinity and increased summer aridity in the Mediterranean Sea. We speculate that these changes triggered an increased MOW flow and were ultimately induced by a persistent 2.5 °C cooling of Indonesian Through-Flow waters. The temperature drop resulted from the northward drift of Australia that crossed a threshold value near 3.6-3.3 Ma and led to a large-scale cooling of the eastern subtropical Indian Ocean and in turn, to a reduction of African monsoon rains. Vice versa, we show that the distinct rise in Mediterranean salt export after 3.4 Ma induced a unique long-term rise in the formation of Upper North Atlantic Deep Water, that followed with a phase lag of 100 ky. In summary, we present evidence for an interhemispheric teleconnection of processes in the Indonesian Gateways, the Mediterranean and Labrador Seas, jointly affecting Pliocene climate.

  6. Wind Diffusivity Current, METOP ASCAT, 0.25 degrees, Global, Near Real Time, Meridional

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes near real time Ekman current (in zonal, meridional, and modulus sets) and Ekman upwelling data. This data begins with wind velocity...

  7. Tracing global biogeochemical cycles and meridional overturning circulation using chromophoric dissolved organic matter

    Science.gov (United States)

    Nelson, Norman B.; Siegel, David A.; Carlson, Craig A.; Swan, Chantal M.

    2010-02-01

    Basin-scale distributions of light absorption by chromophoric dissolved organic matter (CDOM) are positively correlated (R2 > 0.8) with apparent oxygen utilization (AOU) within the top kilometer of the Pacific and Indian Oceans. However, a much weaker correspondence is found for the Atlantic (R2 organic matter from sinking particles. The observed meridional-depth sections of CDOM result from a balance between biogeochemical processes (autochthonous production and solar bleaching) and the meridional overturning circulation. Rapid mixing in the Atlantic dilutes CDOM in the interior and implies that the time scale for CDOM accumulation is greater than ˜50 years. CDOM emerges as a unique tracer for diagnosing changes in biogeochemistry and the overturning circulation, similar to dissolved oxygen, with the additional feature that it can be quantified from satellite observation.

  8. Controlling the structure of forced convective flow by means of rotating magnetic-field inductors

    International Nuclear Information System (INIS)

    Sorkin, M.Z.; Mozgirs, O.Kh.

    1993-01-01

    The forced convective flow generated by a rotating magnetic-field inductor is used in a melt as a means of controlling the transfer of mass and heat in the case of directed crystallization. An obvious advantage in using a rotating field is the generation of azimuthal twisting of the fluid, this providing for an evening out of the crystallization conditions in the azimuthal direction under nonsymmetrical boundary conditions in an actual technological process. From the standpoint of affecting the crystallization processes it would be preferable to use an inductor which would allow alteration of the intensity and of the direction of the meridional flow. Mixing in the form of velocity pulsations generated by the inductor within the melt would be if interest from the standpoint of affecting the crystallization processes, in particular to intensify the crystallization purification. The authors propose the use of a double magnetohydrodynmic rotator which consists of two rotating magnetic-field inductors, separated in altitude, with separate power supplies. The supply of power to the inductors with various current loads allows the generation of a controllable nonuniformity in field distribution and in the azimuthal velocity through the altitude and thus allows control of both the intensity and configuration of the meridional flows. The dual rotator makes it possible to purposefully control the structure of the meridional flows and the pulsation component of velocity and can be recommended for use in processes of directed crystallization as well as in crystallization purification. 4 refs., 3 figs

  9. Effectiveness of Securities with Fuzzy Probabilistic Return

    Directory of Open Access Journals (Sweden)

    Krzysztof Piasecki

    2011-01-01

    Full Text Available The generalized fuzzy present value of a security is defined here as fuzzy valued utility of cash flow. The generalized fuzzy present value cannot depend on the value of future cash flow. There exists such a generalized fuzzy present value which is not a fuzzy present value in the sense given by some authors. If the present value is a fuzzy number and the future value is a random one, then the return rate is given as a probabilistic fuzzy subset on a real line. This kind of return rate is called a fuzzy probabilistic return. The main goal of this paper is to derive the family of effective securities with fuzzy probabilistic return. Achieving this goal requires the study of the basic parameters characterizing fuzzy probabilistic return. Therefore, fuzzy expected value and variance are determined for this case of return. These results are a starting point for constructing a three-dimensional image. The set of effective securities is introduced as the Pareto optimal set determined by the maximization of the expected return rate and minimization of the variance. Finally, the set of effective securities is distinguished as a fuzzy set. These results are obtained without the assumption that the distribution of future values is Gaussian. (original abstract

  10. Agrobiodiversity of cactus pear (Opuntia, Cactaceae in the Meridional Highlands Plateau of Mexico

    Directory of Open Access Journals (Sweden)

    Juan Antonio Reyes-Agüero

    2011-08-01

    Full Text Available Mexico is characterized by a remarkable richness of Opuntia, mostly at the Meridional Highlands Plateau; it is also here where the greatest richness of Opuntia variants occurs. Most of these variants have been maintained in homegardens; however, the gathering process which originated these homegardens has been disrupted over the past decades, as a result of social change and the destruction of large wild nopaleras. If the variants still surviving in homegardens are lost, these will be hard to recover, that is, the millenary cultural heritage from the human groups that populated the Mexican Meridional Highland Plateau will be lost forever. This situation motivated the preparation of a catalogue that records the diversity of wild and cultivated Opuntia variants living in the meridional Highlands Plateau. To this end, 379 samples were obtained in 29 localities, between 1998 and 2003. The information was processed through Twinspan. All specimens were identified and preserved in herbaria. Botanical keys and descriptions were elaborated. The catalogue includes information on 126 variants comprising 18 species. There were species with only one variant (Opuntia atropes, O. cochinera, O. jaliscana, O. leucotricha, O. rzedowskii and O. velutina, two (O. durangensis, O. lindheimeri, O. phaeacantha and O. robusta, five (O. joconostle and O. lasiacantha, seven (O. chavena, 12 (O. hyptiacantha and O. streptacantha, 15 (O. ficus-indica, 22 (O. albicarpa, and up to 34 (O. megacantha. Additionally, 267 common cactus pear names were related to those variants.

  11. Applicability of 87Sr/86Sr in examining return flow of irrigation water in highly agricultural watersheds in Japan

    Science.gov (United States)

    Yoshida, T.; Nakano, T.; Shin, K. C.; Tsuchihara, T.; Miyazu, S.; Kubota, T.

    2017-12-01

    Water flows in watersheds containing extensive areas of irrigated paddies are complex because of the substantial volumes involved and the repeated cycles of water diversion from, and return to, streams. For better management of low-flow conditions, numerous studies have attempted to quantify the return flow using the stable isotopes of water; however, the temporal variation in these isotopic compositions due to fractionation during evaporation from water surfaces hinders their application to watersheds with extensive irrigated paddies. In this study, we tested the applicability of the strontium isotopes (87Sr/86Sr, hereafter Sr ratio) for studying hydrological processes in a typical agricultural watershed located on the alluvial fan of the Kinu River, namely the Gogyo River, in central Japan. The Sr ratio of water changes only because of interactions with the porous media it flows through, or because of mixing with water that has different Sr ratios. We sampled water both at a single rice paddy, and on the watershed scale in the irrigated and non-irrigated periods. The soil water under the paddy decreased as sampling depth increased, and the soil water at a depth of 1.5 m showed a similar Sr ratio to the spring. The water sampled in the drainage channel with a concrete lined bottom showed a similar Sr ratio to the irrigation water, whereas that with a soil bottom was plotted between the plots of the irrigation water and shallow aquifer. These results suggest the Sr ratio decreases as it mixes with the soil water through percolation; whereas the Sr ratio will be less likely to change when water drains from paddies via surface pathways. The streamflow samples were plotted linearly on the Sr ratio and 1/Sr plot, indicating that the streamflow was composed of two end-members; the irrigation water and the shallow aquifer. The continuous decline in the Sr ratio along the stream suggests an exfiltration of water from the shallow aquifers. The stream water during the non

  12. MERIDIONAL COMA OF NEGATIVE ANASTIGMATIC LENSES AT THE FINAL POSITION OF AN OBJECT

    Directory of Open Access Journals (Sweden)

    V. A. Bezrukov

    2015-03-01

    Full Text Available The paper deals with the findings of negative anastigmatic lenses at the final position of an object. The negative lenses are considered with refraction index n=1.7849 (type of glass is TF12 and thickness d=5 mm, working with paraxial magnifications β=1,1x;1,3x;1,5x with account of the distances from the first lens surface to the object S1=9; 25 mm and the size of the object y=15 mm. Dependences of negative lens forms from the position of anastigmatic pupils and from radii of meridional caustics which are convenient for understanding aberrational properties of anastigmatic lenses. The findings give the possibility to synthesize wide-angle lenses with the corrected aberrations of image curvature and meridional coma without geometrical vignetting of wide sloping bunches.

  13. What drives credit rating changes? : a return decomposition approach

    OpenAIRE

    Cho, Hyungjin; Choi, Sun Hwa

    2015-01-01

    This paper examines the relative importance of a shock to expected cash flows (i.e., cash-flow news) and a shock to expected discount rates (i.e., discount-rate news) in credit rating changes. Specifically, we use a Vector Autoregressive model to implement the return decomposition of Campbell and Shiller (Review of Financial Studies, 1, 1988, 195) and Vuolteenaho (Journal of Finance, 57, 2002, 233) to extract cash-flow news and discount-rate news from stock returns at the firm-level. We find ...

  14. The effects of self-generated and applied magnetic fields on the computation of flow over a Mars return aerobrake

    Science.gov (United States)

    Palmer, Grant

    1991-01-01

    A CFD technique is developed to calculate the electromagnetic phenomena simultaneously with the fluid flow in the shock layer over an axisymmetric blunt body in a thermal-equilibrium chemical-nonequilibrium environment. The flowfield is solved using an explicit time-marching, first-order spatially accurate scheme. The electromagnetic phenomena are coupled to the real-gas flow solver through an iterative procedure. The electromagnetic terms introduce a strong stiffness, which was overcome by using significantly smaller time steps for the electromagnetic conservation equation. The technique is applied in calculating the flow over a Mars return aerobrake vehicle entering the Earth's atmosphere. For the case where no external field is applied, the electromagnetic effects have little impact on the flowfield.

  15. Wind Diffusivity Current, QuikSCAT SeaWinds, 0.25 degrees, Global, Science Quality, Meridional

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes science quality Ekman current (in zonal, meridional, and modulus sets) and Ekman upwelling data. This data begins with wind velocity...

  16. Seasonal cycle of cross-equatorial flow in the central Indian Ocean

    Science.gov (United States)

    Wang, Yi; McPhaden, Michael J.

    2017-05-01

    This study investigates the seasonal cycle of meridional currents in the upper layers of central equatorial Indian Ocean using acoustic Doppler current profiler (ADCP) and other data over the period 2004-2013. The ADCP data set collected along 80.5°E is the most comprehensive collection of direct velocity measurements in the central Indian Ocean to date, providing new insights into the meridional circulation in this region. We find that mean volume transport is southward across the equator in the central Indian Ocean in approximate Sverdrup balance with the wind stress curl. In addition, mean westerly wind stress near the equator drives convergent Ekman flow in the surface layer and subsurface divergent geostrophic flow in the thermocline at 50-150 m depths. In response to a mean northward component of the surface wind stress, the maximum surface layer convergence is shifted off the equator to between 0.5° and 1°N. Evidence is also presented for the existence of a shallow equatorial roll consisting of a northward wind-driven surface drift overlaying the southward directed subsurface Sverdrup transport. Seasonal variations are characterized by cross-equatorial transports flowing from the summer to the winter hemisphere in quasi-steady Sverdrup balance with the wind stress curl. In addition, semiannually varying westerly monsoon transition winds lead to semiannual enhancements of surface layer Ekman convergence and geostrophic divergence in the thermocline. These results quantify expectations from ocean circulation theories for equatorial Indian Ocean meridional circulation patterns with a high degree of confidence given the length of the data records.

  17. Improvements in launchings and recipients of PIG in Malha de Gasodutos Nordeste Meridional; Melhorias nos lancamentos e recebedores de PIG da Malha de Gasodutos Nordeste Meridional

    Energy Technology Data Exchange (ETDEWEB)

    Maciel, Jairo A.C.; Lemos, Francisco A.C.; Lima, Artur W.R. de S. [PETROBRAS Transporte S.A. (TRANSPETRO), Rio de Janeiro, RJ (Brazil)

    2012-07-01

    This paper describes the study that resulted in the preparation of a project for improvement of launchers and receivers of PIG in facilities maintained and operated by PETROBRAS S.A. (TRANSPETRO) in the Malha de Gasodutos Nordeste Meridional (Malha NEM). The improvements are part of the component in cleaner production system and reduce the risks of accidents and the costs of hazardous waste management.

  18. Surface changes in the North Atlantic meridional overturning circulation during the last millennium

    DEFF Research Database (Denmark)

    Wanamaker, A.D.; Butler, P.G.; Scourse, J.D.

    2012-01-01

    of decadal-to-centennial scale changes in Atlantic meridional overturning circulation strength in regulating the climate of the last millennium. Here we use the time-constrained high-resolution local radiocarbon reservoir age offset derived from an absolutely dated annually resolved shell chronology spanning...

  19. The influence of meridional ice transport on Europa's ocean stratification and heat content

    Science.gov (United States)

    Zhu, P.; Manucharyan, G.; Thompson, A. F.; Goodman, J. C.; Vance, S.

    2017-12-01

    Jupiter's moon Europa likely hosts a saltwater ocean beneath its icy surface. Geothermal heating and rotating convection in the ocean may drive a global overturning circulation that redistributes heat vertically and meridionally, preferentially warming the ice shell at the equator. Here we assess thepreviously unconstrained influence of ocean-ice coupling on Europa's ocean stratification and heat transport. We demonstrate that a relatively fresh layer can form at the ice-ocean interface due to a meridional ice transport forced by the differential ice shell heating between the equator and the poles. We provide analytical and numerical solutions for the layer's characteristics, highlighting their sensitivity to critical ocean parameters. For a weakly turbulent and highly saline ocean, a strong buoyancy gradient at the base of the freshwater layer can suppress vertical tracer exchange with the deeper ocean. As a result, the freshwater layer permits relatively warm deep ocean temperatures.

  20. Meridional overturning and large-scale circulation of the Indian Ocean

    Science.gov (United States)

    Ganachaud, Alexandre; Wunsch, Carl; Marotzke, Jochem; Toole, John

    2000-11-01

    The large scale Indian Ocean circulation is estimated from a global hydrographic inverse geostrophic box model with a focus on the meridional overturning circulation (MOC). The global model is based on selected recent World Ocean Circulation Experiment (WOCE) sections which in the Indian Basin consist of zonal sections at 32°S, 20°S and 8°S, and a section between Bali and Australia from the Java-Australia Dynamic Experiment (JADE). The circulation is required to conserve mass, salinity, heat, silica and "PO" (170PO4+O2). Near-conservation is imposed within layers bounded by neutral surfaces, while permitting advective and diffusive exchanges between the layers. Conceptually, the derived circulation is an estimate of the average circulation for the period 1987-1995. A deep inflow into the Indian Basin of 11±4 Sv is found, which is in the lower range of previous estimates, but consistent with conservation requirements and the global data set. The Indonesian Throughflow (ITF) is estimated at 15±5 Sv. The flow in the Mozambique Channel is of the same magnitude, implying a weak net flow between Madagascar and Australia. A net evaporation of -0.6±0.4 Sv is found between 32°S and 8°S, consistent with independent estimates. No net heat gain is found over the Indian Basin (0.1 ± 0.2PW north of 32°S) as a consequence of the large warm water influx from the ITF. Through the use of anomaly equations, the average dianeutral upwelling and diffusion between the sections are required and resolved, with values in the range 1-3×10-5 cm s-1 for the upwelling and 2-10 cm2 s-1 for the diffusivity.

  1. Performance Improvement of a Return Channel in a Multistage Centrifugal Compressor Using Multiobjective Optimization.

    Science.gov (United States)

    Nishida, Yoshifumi; Kobayashi, Hiromi; Nishida, Hideo; Sugimura, Kazuyuki

    2013-05-01

    The effect of the design parameters of a return channel on the performance of a multistage centrifugal compressor was numerically investigated, and the shape of the return channel was optimized using a multiobjective optimization method based on a genetic algorithm to improve the performance of the centrifugal compressor. The results of sensitivity analysis using Latin hypercube sampling suggested that the inlet-to-outlet area ratio of the return vane affected the total pressure loss in the return channel, and that the inlet-to-outlet radius ratio of the return vane affected the outlet flow angle from the return vane. Moreover, this analysis suggested that the number of return vanes affected both the loss and the flow angle at the outlet. As a result of optimization, the number of return vane was increased from 14 to 22 and the area ratio was decreased from 0.71 to 0.66. The radius ratio was also decreased from 2.1 to 2.0. Performance tests on a centrifugal compressor with two return channels (the original design and optimized design) were carried out using two-stage test apparatus. The measured flow distribution exhibited a swirl flow in the center region and a reversed swirl flow near the hub and shroud sides. The exit flow of the optimized design was more uniform than that of the original design. For the optimized design, the overall two-stage efficiency and pressure coefficient were increased by 0.7% and 1.5%, respectively. Moreover, the second-stage efficiency and pressure coefficient were respectively increased by 1.0% and 3.2%. It is considered that the increase in the second-stage efficiency was caused by the increased uniformity of the flow, and the rise in the pressure coefficient was caused by a decrease in the residual swirl flow. It was thus concluded from the numerical and experimental results that the optimized return channel improved the performance of the multistage centrifugal compressor.

  2. Return to nucleate boiling

    International Nuclear Information System (INIS)

    Shumway, R.W.

    1985-01-01

    This paper presents a collection of TMIN (temperature of return to nucleate boiling) correlations, evaluates them under several conditions, and compares them with a wide range of data. Purpose is to obtain the best one for use in a water reactor safety computer simulator known as TRAC-B. Return to nucleate boiling can occur in a reactor accident at either high or low pressure and flow rates. Most of the correlations yield unrealistic results under some conditions. A new correlation is proposed which overcomes many of the deficiencies

  3. Incorporating a Time Horizon in Rate-of-Return Estimations: Discounted Cash Flow Model in Electric Transmission Rate Cases

    International Nuclear Information System (INIS)

    Chatterjee, Bishu; Sharp, Peter A.

    2006-01-01

    Electric transmission and other rate cases use a form of the discounted cash flow model with a single long-term growth rate to estimate rates of return on equity. It cannot incorporate information about the appropriate time horizon for which analysts' estimates of earnings growth have predictive powers. Only a non-constant growth model can explicitly recognize the importance of the time horizon in an ROE calculation. (author)

  4. A new method to estimate risk and return of non-traded assets from cash flows : The case of private equity funds

    NARCIS (Netherlands)

    Driessen, J.J.A.G.; Lin, T.C.; Phalippou, L.

    2012-01-01

    We develop a new methodology to estimate abnormal performance and risk exposure of nontraded assets from cash flows. Our methodology extends the standard internal rate of return approach to a dynamic setting. The small-sample properties are validated using a simulation study. We apply the method to

  5. The Emergence of the Pacific Meridional Overturning Circulation (PMOC) Paced by Obliquity Cycles during the Pliocene

    Science.gov (United States)

    Burls, N.; Fedorov, A. V.; Sigman, D. M.; Jaccard, S.; Tiedemann, R.; Haug, G. H.

    2016-12-01

    Deep water formation in northern high latitudes, as part of the Atlantic meridional overturning circulation (AMOC), is a critical element of modern ocean circulation and climate. For the warm Pliocene, roughly 4 to 2.8 million years ago, we present measurements and modeling evidence that deep water formation also occurred in the North Pacific, supporting another overturning cell - the Pacific meridional overturning circulation (PMOC). The evidence includes calcium carbonate accumulation in Pliocene subarctic Pacific sediments rivaling that of the modern North Atlantic, with pigment, total organic carbon, and redox-sensitive trace metal measurements supporting deep ocean ventilation as the driver of the enhanced calcium carbonate preservation. Together with high accumulation rates of biogenic opal, this implies a bi-directional communication between surface waters and the waters overlying the deep seafloor, and hence deep convection. A Pliocene-like climate simulation reproduces this deep water formation, with co-occurring Atlantic and Pacific overturning cells. The PMOC emerges as a result of the less intense hydrological cycle under Pliocene conditions characterized by a reduced meridional SST gradient. This weaker hydrological cycle leads to the erosion of the North Pacific halocline, allowing deep convection. Examining the data in more detail shows that, while the opal accumulation rate was continuously high, maxima in calcium carbonate accumulation rate were sharp and intermittent. Most likely, these maxima occurred during Northern Hemisphere summer insolation maxima when, as supported by the modeling results, mid-latitude SSTs in the Northern Hemisphere were at a maximum and the meridional SST gradient was particularly weak. These findings suggest that the climate system fluctuated between periods of strong and weak PMOC during the Pliocene. Such fluctuations appear to be a crucial part of Pliocene climate variability on orbital timescales.

  6. DAMPAK PEMODERASIAN KOMPONEN ARUS KAS TERHADAP HUBUNGAN LABA AKUNTANSI DENGAN RETURN SAHAM

    Directory of Open Access Journals (Sweden)

    Hendy Hermawan

    2012-02-01

    Full Text Available Accurate information regarding listed companies is crucial to minimize investment risk. This research aims to examine the effect of accounting income on stock return, and the effect of cash flow from operation, cash flow from investment, and cash flow from financing activities respectively as moderating variables on the relationship between accounting income and stock return of manufacturer listed on the Jakarta Stock Exchange. There were 161 manufacturing companies listed during 2001 to 2005, and 39 of them are selected as sample research using purposive sampling method. With 5 year research period, there are 195 observations done. Data then are analyzed using multiple linear regressions. Results show that accounting income affect stock return significantly, which is shown by greater value of t count compare to t table. While cash flow from operation, investment, and financing activities are not able to moderate relationship between accounting income and stock return

  7. Tuning facial-meridional isomerisation in monometallic nine-co-ordinate lanthanide complexes with unsymmetrical tridentate ligands.

    Science.gov (United States)

    Le Borgne, Thierry; Altmann, Peter; André, Nicolas; Bünzli, Jean-Claude G; Bernardinelli, Gérald; Morgantini, Pierre-Yves; Weber, Jacques; Piguet, Claude

    2004-03-07

    The unsymmetrical tridentate benzimidazole-pyridine-carboxamide units in ligands L1-L4 react with trivalent lanthanides, Ln(III), to give the nine-co-ordinate triple-helical complexes [Ln(Li)3]3+ (i = 1-4) existing as mixtures of C3-symmetrical facial and C1-symmetrical meridional isomers. Although the beta13 formation constants are 3-4 orders of magnitude smaller for these complexes than those found for the D3-symmetrical analogues [Ln(Li)3]3+ (i = 5-6) with symmetrical ligands, their formation at the millimolar scale is quantitative and the emission quantum yield of [Eu(L2)3]3+ is significantly larger. The fac-[Ln(Li)3]3+ mer-[Ln(Li)3]3+ (i = 1-4) isomerisation process in acetonitrile is slow enough for Ln = Lu(III) to be quantified by 1H NMR below room temperature. The separation of enthalpic and entropic contributions shows that the distribution of the facial and meridional isomers can be tuned by the judicious peripheral substitution of the ligands affecting the interstrand interactions. Molecular mechanics (MM) calculations suggest that one supplementary interstrand pi-stacking interaction stabilises the meridional isomers, while the facial isomers benefit from more favourable electrostatic contributions. As a result of the mixture of facial and meridional isomers in solution, we were unable to obtain single crystals of 1:3 complexes, but the X-ray crystal structures of their nine-co-ordinate precursors [Eu(L1)2(CF3SO3)2(H2O)](CF3SO3)(C3H5N)2(H2O) (6, C45H54EuF9N10O13S3, monoclinic, P2(1)/c, Z = 4) and [Eu(L4)2(CF3SO3)2(H2O)](CF3SO3)(C4H4O)(1.5) (7, C51H66EuF9N8O(15.5)S3, triclinic, P1, Z = 2) provide crucial structural information on the binding mode of the unsymmetrical tridentate ligands.

  8. Temporal Variation of Large Scale Flows in the Solar Interior ...

    Indian Academy of Sciences (India)

    tribpo

    Temporal Variation of Large Scale Flows in the Solar Interior. 355. Figure 2. Zonal and meridional components of the time-dependent residual velocity at a few selected depths as marked above each panel, are plotted as contours of constant velocity in the longitude-latitude plane. The left panels show the zonal component, ...

  9. Non-return valve, more particularly for PWR

    International Nuclear Information System (INIS)

    Panet, M.; Martin, R.

    1987-01-01

    This non-return valve has a tubular body containing an axially sliding piston. The sliding piston delimits a cylinder cooperating with a valve seat to block fluid flow in one direction and a flow restrictor downstream of the seat in the other direction [fr

  10. Internal Flow of a High Specific-Speed Diagonal-Flow Fan (Rotor Outlet Flow Fields with Rotating Stall

    Directory of Open Access Journals (Sweden)

    Norimasa Shiomi

    2003-01-01

    Full Text Available We carried out investigations for the purpose of clarifying the rotor outlet flow fields with rotating stall cell in a diagonal-flow fan. The test fan was a high–specific-speed (ns=1620 type of diagonal-flow fan that had 6 rotor blades and 11 stator blades. It has been shown that the number of the stall cell is 1, and its propagating speed is approximately 80% of its rotor speed, although little has been known about the behavior of the stall cell because a flow field with a rotating stall cell is essentially unsteady. In order to capture the behavior of the stall cell at the rotor outlet flow fields, hot-wire surveys were performed using a single-slant hotwire probe. The data obtained by these surveys were processed by means of a double phase-locked averaging technique, which enabled us to capture the flow field with the rotating stall cell in the reference coordinate system fixed to the rotor. As a result, time-dependent ensemble averages of the three-dimensional velocity components at the rotor outlet flow fields were obtained. The behavior of the stall cell was shown for each velocity component, and the flow patterns on the meridional planes were illustrated.

  11. Stock Return and Cash Flow Predictability: The Role of Volatility Risk

    DEFF Research Database (Denmark)

    Bollerslev, Tim; Xu, Lai; Zhou, Hao

    risk premium positively forecast both short-horizon returns and dividend growth rates. We also confirm that dividend yield positively forecasts long-horizon returns, but that it cannot forecast dividend growth rates. Our equilibrium-based “structural” factor GARCH model permits much more accurate...

  12. Modifying cochlear implant design: advantages of placing a return electrode in the modiolus.

    Science.gov (United States)

    Ho, Steven Y; Wiet, Richard J; Richter, Claus-Peter

    2004-07-01

    A modiolar return electrode significantly increases the current flow across spiral ganglion cells into the modiolus, and may decrease the cochlear implant's power requirements. Ideal cochlear implants should maximize current flow into the modiolus to stimulate auditory neurons. Previous efforts to facilitate current flow through the modiolus included the fabrication and use of precurved electrodes designed to "hug" the modiolus and silastic positioners designed to place the electrodes closer to the modiolus. In contrast to earlier efforts, this study explores the effects of return electrode placement on current distributions in the modiolus. The effects of return electrode positioning on current flow in the modiolus were studied in a Plexiglas model of the cochlea. Results of model measurements were confirmed by measurements in the modiolus of human temporal bones. The return electrode was placed either within the modiolus, or remotely, outside the temporal bone, simulating contemporary cochlear implant configurations using monopolar stimulation. Cochlear model results clearly show that modiolar current amplitudes can be influenced significantly by the location of the return electrode, being larger when placed into the modiolus. Temporal bone data show similar findings. Voltages recorded in the modiolus are, on average, 2.8 times higher with the return electrode in the modiolus compared with return electrode locations outside the temporal bone. Placing a cochlear implant's return electrode in the modiolus should significantly reduce its power consumption. Reducing power requirements should lead to improved efficiency, safer long-term use, and longer device life.

  13. Multiobjective genetic algorithm conjunctive use optimization for production, cost, and energy with dynamic return flow

    Science.gov (United States)

    Peralta, Richard C.; Forghani, Ali; Fayad, Hala

    2014-04-01

    Many real water resources optimization problems involve conflicting objectives for which the main goal is to find a set of optimal solutions on, or near to the Pareto front. E-constraint and weighting multiobjective optimization techniques have shortcomings, especially as the number of objectives increases. Multiobjective Genetic Algorithms (MGA) have been previously proposed to overcome these difficulties. Here, an MGA derives a set of optimal solutions for multiobjective multiuser conjunctive use of reservoir, stream, and (un)confined groundwater resources. The proposed methodology is applied to a hydraulically and economically nonlinear system in which all significant flows, including stream-aquifer-reservoir-diversion-return flow interactions, are simulated and optimized simultaneously for multiple periods. Neural networks represent constrained state variables. The addressed objectives that can be optimized simultaneously in the coupled simulation-optimization model are: (1) maximizing water provided from sources, (2) maximizing hydropower production, and (3) minimizing operation costs of transporting water from sources to destinations. Results show the efficiency of multiobjective genetic algorithms for generating Pareto optimal sets for complex nonlinear multiobjective optimization problems.

  14. Estimates of Lagrangian particle transport by wave groups: forward transport by Stokes drift and backward transport by the return flow

    Science.gov (United States)

    van den Bremer, Ton S.; Taylor, Paul H.

    2014-11-01

    Although the literature has examined Stokes drift, the net Lagrangian transport by particles due to of surface gravity waves, in great detail, the motion of fluid particles transported by surface gravity wave groups has received considerably less attention. In practice nevertheless, the wave field on the open sea often has a group-like structure. The motion of particles is different, as particles at sufficient depth are transported backwards by the Eulerian return current that was first described by Longuet-Higgins & Stewart (1962) and forms an inseparable counterpart of Stokes drift for wave groups ensuring the (irrotational) mass balance holds. We use WKB theory to study the variation of the Lagrangian transport by the return current with depth distinguishing two-dimensional seas, three-dimensional seas, infinite depth and finite depth. We then provide dimensional estimates of the net horizontal Lagrangian transport by the Stokes drift on the one hand and the return flow on the other hand for realistic sea states in all four cases. Finally we propose a simple scaling relationship for the transition depth: the depth above which Lagrangian particles are transported forwards by the Stokes drift and below which such particles are transported backwards by the return current.

  15. Controls on the meridional extent of tropical precipitation and its contraction under global warming

    Science.gov (United States)

    Donohoe, A.

    2017-12-01

    A method for decomposing changes and variability in the spatial structure of tropical precipitation into shifting (meridional translation), contracting, and intensifying modes of variability is introduced. We demonstrate that the shifting mode of tropical precipitation explains very little (20%) more of the tropical precipitation changes and variability. Furthermore, the contraction of tropical precipitation is highly correlated (R2 > 0.95) with an intensification of the precipitation in both the observations and forced modeled simulations. These results suggest that the simultaneous contraction and intensification of tropical precipitation is the dominant mode of variability and changes under external forcing. We speculate that tropical surface temperature controls this concurrent variability. Indeed, models robustly predict that tropical precipitation increases and meridionally contracts in response to increased CO2 and is reduced and meridionally expanded under glacial forcing and boundary conditions. In contrast, the directionality of the tropical precipitation shift is both ambiguous and small in magnitude in response to increased CO2. Furthermore, the ratio of the contraction/expansion to intensification/reduction is consistent in the continuum of climate states from the glacial climate to a modern climate to a 4XCO2 climate suggesting that the intensification and contraction are linked together via a single mechanism. We examine two mechanisms responsible for the contraction of the precipitation under global warming : i. the reduction of the seasonal cycle of energy input to the atmosphere due to sea ice retreat that results in the tropical precipitation remaining closer to the equator during the solsticial seasons and; ii. the increased gross moist stability of the tropical atmosphere as the surface warms resulting in a weaker cross-equatorial Hadley circulation during the solsticial seasons.

  16. DAMPAK PEMODERASIAN KOMPONEN ARUS KAS TERHADAP HUBUNGAN LABA AKUNTANSI DENGAN RETURN SAHAM

    Directory of Open Access Journals (Sweden)

    PUTU ARI DHARMA LAKSMI

    2009-07-01

    Full Text Available Accurate information regarding listed companies is crucial tominimize investment risk. This research aims to examine the effect ofaccounting income on stock return, and the effect of cash flow fromoperation, cash flow from investment, and cash flow from financingactivities respectively as moderating variables on the relationshipbetween accounting income and stock return of manufacturer listedon the Jakarta Stock Exchange.There were 161 manufacturing companies listed during 2001to 2005, and 39 of them are selected as sample research usingpurposive sampling method. With 5 year research period, there are195 observations done. Data then are analyzed using multiple linearregressions.Results show that accounting income affect stock returnsignificantly, which is shown by greater value of t count compare to ttable. While cash flow from operation, investment, and financingactivities are not able to moderate relationship between accountingincome and stock return.

  17. The role of meltwater-induced subsurface ocean warming in regulating the Atlantic meridional overturning in glacial climate simulations

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Esther C.; Otto-Bliesner, Bette L. [National Center for Atmospheric Research, Boulder, CO (United States)

    2011-10-15

    The Community Climate System Model version 3, (CCSM3) is used to investigate the effect of the high latitude North Atlantic subsurface ocean temperature response in idealized freshwater hosing experiments on the strength of the Atlantic meridional overturning circulation (AMOC). The hosing experiments covered a range of input magnitudes at two locations in a glacial background state. Subsurface subpolar ocean warms when freshwater is added to the high latitude North Atlantic (NATL cases) and weakly cools when freshwater is added to the Gulf of Mexico (GOM cases). All cases show subsurface ocean warming in the Southern Hemisphere (SH). The sensitivity of the AMOC response to the location and magnitude of hosing is related to the induced subsurface temperature response, which affects the magnitude of the large-scale meridional pressure gradient at depth through the effect on upper ocean density. The high latitude subsurface warming induced in the NATL cases lowers the upper ocean density in the deepwater formation region enhancing a density reduction by local freshening. In the GOM cases the effect of SH warming partially offsets the effect of the high latitude freshening on the meridional density gradient. Following the end of hosing, a brief convective event occurs in the largest NATL cases which flushes some of the heat stored in the subsurface layers. This fuels a rapid rise in AMOC that lasts less than a couple of decades before subsequent freshening from increases in precipitation and sea ice melt reverses the initial increase in the meridional density gradient. Thereafter AMOC recovery slows to the rate found in comparable GOM cases. The result for these glacial transient hosing experiments is that the pace of the longer recovery is not sensitive to location of the imposed freshwater forcing. (orig.)

  18. Melt Motion Due to Peltier Marking During Bridgman Crystal Growth with an Axial Magnetic Field

    Science.gov (United States)

    Sellers, C. C.; Walker, John S.; Szofran, Frank R.; Motakef, Shariar

    2000-01-01

    This paper treats a liquid-metal flow inside an electrically insulating cylinder with electrically conducting solids above and below the liquid region. There is a uniform axial magnetic field, and there is an electric current through the liquid and both solids. Since the lower liquid-solid interface is concave into the solid and since the liquid is a better electrical conductor than the adjacent solid, the electric current is locally concentrated near the centerline. The return to a uniform current distribution involves a radial electric current which interacts with the axial magnetic field to drive an azimuthal flow. The axial variation of the centrifugal force due to the azimuthal velocity drives a meridional circulation with radial and axial velocities. This problem models the effects of Peltier marking during the vertical Bridgman growth of semiconductor crystals with an externally applied magnetic field, where the meridional circulation due to the Peltier Current may produce important mixing in the molten semiconductor.

  19. Solar rotation and meridional motions derived from sunspot groups

    International Nuclear Information System (INIS)

    Tuominen, J.; Tuominen, I.; Kyroelaeinen, J.

    1982-01-01

    Latitudinal and longitudinal motions of sunspot groups have been studied using the positions of recurrent sunspot groups of 103 years published by Greenwich observatory. In order to avoid any limb effects, only positions close to the central meridian have been used. The data were divided into two parts: those belonging to the years around sunspot maxima and those belonging to the years around sunspot minima. Using several different criteria it was ascertained that sunspot groups show meridional motions and that their drift curves as a function of latitude are different around maxima and around minima. In addition, also the angular velocity, as a function of latitude, was found to be different around maxima and minima. (Auth.)

  20. Returning home

    DEFF Research Database (Denmark)

    Agergaard, Jytte; Brøgger, Ditte

    2016-01-01

    flows. By focusing on these educational migrants, this paper explores how they connect to their rural homes. Guided by a critical reading of the migration-development scholarship, the paper examines how migrants and their relatives make sense of educational migrants’ remitting and returning practices......, and by comparing three groups of educational migrants, the migrants’ reasons for staying connected and sending remittances are scrutinized. The paper finds that although educational migrants do not generate extensive economic remittances for local development in Nepal, they stay connected to their rural homes...

  1. Impacts of Arctic precipitation changes on the downwelling limb of the Atlantic Meridional Overturning Circulation

    NARCIS (Netherlands)

    Katsman, C.A.; van der Sleen, N.; Bintanja, Richard; Selten, F.; Wijnberg, Kathelijne Mariken; Hulscher, Suzanne J.M.H.

    2018-01-01

    According to the latest IPCC report, under the RCP 8.5 scenario precipitation in the Arctic region may increase by as much as 50%. The projected 21stcentury decline of the Atlantic Meridional Overturning Circulation (AMOC) is attributed in part to this increase in precipitation and the associated

  2. The Canary Basin contribution to the seasonal cycle of the Atlantic Meridional Overturning Circulation at 26°N

    Science.gov (United States)

    Pérez-Hernández, M. D.; McCarthy, G. D.; Vélez-Belchí, P.; Smeed, D. A.; Fraile-Nuez, E.; Hernández-Guerra, A.

    2015-11-01

    This study examines the seasonal cycle of the Atlantic Meridional Overturning Circulation (AMOC) and its eastern boundary contributions. The cycle has a magnitude of 6 Sv, as measured by the RAPID/MOCHA/WBTS project array at 26°N, which is driven largely by the eastern boundary. The eastern boundary variations are explored in the context of the regional circulation around the Canary Islands. There is a 3 month lag between maximum wind forcing and the largest eastern boundary transports, which is explained in terms of a model for Rossby wave generated at the eastern boundary. Two dynamic processes take place through the Lanzarote Passage (LP) in fall: the recirculation of the Canary Current and the northward flow of the Intermediate Poleward Undercurrent. In contrast, during the remaining seasons the transport through the LP is southward due to the Canary Upwelling Current. These processes are linked to the seasonal cycle of the AMOC.

  3. Hydraulic performance numerical simulation of high specific speed mixed-flow pump based on quasi three-dimensional hydraulic design method

    International Nuclear Information System (INIS)

    Zhang, Y X; Su, M; Hou, H C; Song, P F

    2013-01-01

    This research adopts the quasi three-dimensional hydraulic design method for the impeller of high specific speed mixed-flow pump to achieve the purpose of verifying the hydraulic design method and improving hydraulic performance. Based on the two families of stream surface theory, the direct problem is completed when the meridional flow field of impeller is obtained by employing iterative calculation to settle the continuity and momentum equation of fluid. The inverse problem is completed by using the meridional flow field calculated in the direct problem. After several iterations of the direct and inverse problem, the shape of impeller and flow field information can be obtained finally when the result of iteration satisfies the convergent criteria. Subsequently the internal flow field of the designed pump are simulated by using RANS equations with RNG k-ε two-equation turbulence model. The static pressure and streamline distributions at the symmetrical cross-section, the vector velocity distribution around blades and the reflux phenomenon are analyzed. The numerical results show that the quasi three-dimensional hydraulic design method for high specific speed mixed-flow pump improves the hydraulic performance and reveal main characteristics of the internal flow of mixed-flow pump as well as provide basis for judging the rationality of the hydraulic design, improvement and optimization of hydraulic model

  4. The role of the meridional sea surface temperature gradient in controlling the Caribbean low-level jet

    Science.gov (United States)

    Maldonado, Tito; Rutgersson, Anna; Caballero, Rodrigo; Pausata, Francesco S. R.; Alfaro, Eric; Amador, Jorge

    2017-06-01

    The Caribbean low-level jet (CLLJ) is an important modulator of regional climate, especially precipitation, in the Caribbean and Central America. Previous work has inferred, due to their semiannual cycle, an association between CLLJ strength and meridional sea surface temperature (SST) gradients in the Caribbean Sea, suggesting that the SST gradients may control the intensity and vertical shear of the CLLJ. In addition, both the horizontal and vertical structure of the jet have been related to topographic effects via interaction with the mountains in Northern South America (NSA), including funneling effects and changes in the meridional geopotential gradient. Here we test these hypotheses, using an atmospheric general circulation model to perform a set of sensitivity experiments to examine the impact of both SST gradients and topography on the CLLJ. In one sensitivity experiment, we remove the meridional SST gradient over the Caribbean Sea and in the other, we flatten the mountains over NSA. Our results show that the SST gradient and topography have little or no impact on the jet intensity, vertical, and horizontal wind shears, contrary to previous works. However, our findings do not discount a possible one-way coupling between the SST and the wind over the Caribbean Sea through friction force. We also examined an alternative approach based on barotropic instability to understand the CLLJ intensity, vertical, and horizontal wind shears. Our results show that the current hypothesis about the CLLJ must be reviewed in order to fully understand the atmospheric dynamics governing the Caribbean region.

  5. Further influence of the eastern boundary on the seasonal variability of the Atlantic Meridional Overturning Circulation at 26N

    Science.gov (United States)

    Baehr, Johanna; Schmidt, Christian

    2016-04-01

    The seasonal cycle of the Atlantic Meridional Overturning Circulation (AMOC) at 26.5 N has been shown to arise predominantly from sub-surface density variations at the Eastern boundary. Here, we suggest that these sub-surface density variations have their origin in the seasonal variability of the Canary Current system, in particular the Poleward Undercurrent (PUC). We use a high-resolution ocean model (STORM) for which we show that the seasonal variability resembles observations for both sub-surface density variability and meridional transports. In particular, the STORM model simulation density variations at the eastern boundary show seasonal variations reaching down to well over 1000m, a pattern that most model simulations systematically underestimate. We find that positive wind stress curl anomalies in late summer and already within one degree off the eastern boundary result -through water column stretching- in strong transport anomlies in PUC in fall, coherent down to 1000m depth. Simultaneously with a westward propagation of these transport anomalies, we find in winter a weak PUC between 200 m and 500m, and southward transports between 600m and 1300m. This variability is in agreement with the observationally-based suggestion of a seasonal reversal of the meridional transports at intermediate depths. Our findings extend earlier studies which suggested that the seasonal variability at of the meridional transports across 26N is created by changes in the basin-wide thermocline through wind-driven upwelling at the eastern boundary analyzing wind stress curl anomalies 2 degrees off the eastern boundary. Our results suggest that the investigation of AMOC variability and particular its seasonal cycle modulations require the analysis of boundary wind stress curl and the upper ocean transports within 1 degree off the eastern boundary. These findings also implicate that without high-resolution coverage of the eastern boundary, coarser model simulation might not fully

  6. Meridional Motions and Reynolds Stress Determined by Using Kanzelhöhe Drawings and White Light Solar Images from 1964 to 2016

    Science.gov (United States)

    Ruždjak, Domagoj; Sudar, Davor; Brajša, Roman; Skokić, Ivica; Poljančić Beljan, Ivana; Jurdana-Šepić, Rajka; Hanslmeier, Arnold; Veronig, Astrid; Pötzi, Werner

    2018-04-01

    Sunspot position data obtained from Kanzelhöhe Observatory for Solar and Environmental Research (KSO) sunspot drawings and white light images in the period 1964 to 2016 were used to calculate the rotational and meridional velocities of the solar plasma. Velocities were calculated from daily shifts of sunspot groups and an iterative process of calculation of the differential rotation profiles was used to discard outliers. We found a differential rotation profile and meridional motions in agreement with previous studies using sunspots as tracers and conclude that the quality of the KSO data is appropriate for analysis of solar velocity patterns. By analyzing the correlation and covariance of meridional velocities and rotation rate residuals we found that the angular momentum is transported towards the solar equator. The magnitude and latitudinal dependence of the horizontal component of the Reynolds stress tensor calculated is sufficient to maintain the observed solar differential rotation profile. Therefore, our results confirm that the Reynolds stress is the dominant mechanism responsible for transport of angular momentum towards the solar equator.

  7. Financial modeling in medicine: cash flow, basic metrics, the time value of money, discount rates, and internal rate of return.

    Science.gov (United States)

    Lexa, Frank James; Berlin, Jonathan W

    2005-03-01

    In this article, the authors cover tools for financial modeling. Commonly used time lines and cash flow diagrams are discussed. Commonly used but limited terms such as payback and breakeven are introduced. The important topics of the time value of money and discount rates are introduced to lay the foundation for their use in modeling and in more advanced metrics such as the internal rate of return. Finally, the authors broach the more sophisticated topic of net present value.

  8. Asset securitization and rate of return: A study on letters of guarantee

    Science.gov (United States)

    Wu, Binghui

    2018-01-01

    Using the theory of asset securitization, we analyze the feasibility of the securitization of letters of guarantee in theory. In the process of constructing the model of rate of return of securities backed by letters of guarantee, we propose two indices: the risk probability of asset-backed securities and the loss rate of asset-backed securities to analyze the cash flow of securities. On the basis of no arbitrage principle, the expression of rate of return of securities backed by letters of guarantee is put forward. In order to study the relationship between the rate of return of securities and other influential factor in the model, a simulation experiment is designed. The experiment results show that (i) an increasing risk probability of cash flow or a short maturity date also make the return rate of securities increase and (ii) the return rate of securities is higher in economic boom than that in economic recession when other parameters remain unchanged.

  9. Conference on Fluid Machinery, 8th, Budapest, Hungary, Sept. 1987, Proceedings. Volumes 1 & 2

    Science.gov (United States)

    Szabo, A.; Kisbocskoi, L.

    The present conference on turbomachine fluid mechanics gives attention to the analysis of labyrinth seals, irrigation turbomachinery, axial-flow fans, poppet valves, the generation of Karman vortices, self-rectifying Wells-type air turbines, computer simulations for water-supply systems, the computation of meridional flow in turbomachines, entrained air effects on vortex pump performance, the three-dimensional potential flow in a draft tube, and hydro powerplant diagnostic methods. Also discussed are a mathematical model for the initiation of cavitation wear, cryogenic flow in ejectors, flow downstream of guide vanes in a Kaplan turbine, unsteady flow in rotating cascades, novel methods for turbomachine vibration monitoring, cavitation breakdown in centrifugal pumps, test results for Banki turbines, centrifugal compressor return-channel flow, performance predictions for regenerative turbomachines, and secondary flows in a centrifugal pump.

  10. The effects of return on investment, sales growth rate, volatility of investment, cash flow and structure of institutional shareholders on the ratio of debt to equities

    Directory of Open Access Journals (Sweden)

    Jalal Golmohammadi

    2015-12-01

    Full Text Available This paper presents a study to measure the effects of return on investment, sales growth rate, volatility investment, cash flow and structure of institutional shareholders on the ratio of debt to equities. The study selects 102 firms listed on Tehran Stock Exchange and, using regression technique with Panel data, examines five different hypotheses over the period 2008-2012. The results indicate that there was a negative and meaningful relationship between return of investment and the ratio of debt to equities and a positive and meaningful relationship between sales growth and the ratio of debt to equities. Moreover, there were positive and meaningful relationships between volatility of investment as well as cash flow and the ratio of debt to equities. Finally, the survey has indicated that there was a negative and meaningful relationship between the structure of institutional shareholders and the ratio of debt to equities.

  11. Solar Dynamo Driven by Periodic Flow Oscillation

    Science.gov (United States)

    Mayr, Hans G.; Hartle, Richard E.; Einaudi, Franco (Technical Monitor)

    2001-01-01

    We have proposed that the periodicity of the solar magnetic cycle is determined by wave mean flow interactions analogous to those driving the Quasi Biennial Oscillation in the Earth's atmosphere. Upward propagating gravity waves would produce oscillating flows near the top of the radiation zone that in turn would drive a kinematic dynamo to generate the 22-year solar magnetic cycle. The dynamo we propose is built on a given time independent magnetic field B, which allows us to estimate the time dependent, oscillating components of the magnetic field, (Delta)B. The toroidal magnetic field (Delta)B(sub phi) is directly driven by zonal flow and is relatively large in the source region, (Delta)(sub phi)/B(sub Theta) much greater than 1. Consistent with observations, this field peaks at low latitudes and has opposite polarities in both hemispheres. The oscillating poloidal magnetic field component, (Delta)B(sub Theta), is driven by the meridional circulation, which is difficult to assess without a numerical model that properly accounts for the solar atmosphere dynamics. Scale-analysis suggests that (Delta)B(sub Theta) is small compared to B(sub Theta) in the dynamo region. Relative to B(sub Theta), however, the oscillating magnetic field perturbations are expected to be transported more rapidly upwards in the convection zone to the solar surface. As a result, (Delta)B(sub Theta) (and (Delta)B(sub phi)) should grow relative to B(sub Theta), so that the magnetic fields reverse at the surface as observed. Since the meridional and zonai flow oscillations are out of phase, the poloidal magnetic field peaks during times when the toroidal field reverses direction, which is observed. With the proposed wave driven flow oscillation, the magnitude of the oscillating poloidal magnetic field increases with the mean rotation rate of the fluid. This is consistent with the Bode-Blackett empirical scaling law, which reveals that in massive astrophysical bodies the magnetic moment tends

  12. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    The deceleration of the meridional flow is strongly modulated by the inertial effects due to the meridional advection of zonal momentum in addition to the terms in the simple balance. The simple balance predicts a spurious near equatorial convergence and a consistent off-equatorial convergence of the meridional flow.

  13. Effects of reduced return activated sludge flows and volume on anaerobic zone performance for a septic wastewater biological phosphorus removal system.

    Science.gov (United States)

    Magro, Daniel; Elias, Steven L; Randall, Andrew Amis

    2005-01-01

    Enhanced biological phosphorous removal (EBPR) performance was found to be adequate with reduced return-activated sludge (RAS) flows (50% of available RAS) to the anaerobic tank and smaller-than-typical anaerobic zone volume (1.08 hours hydraulic retention time [HRT]). Three identical parallel biological nutrient removal pilot plants were fed with strong, highly fermented (160 mg/L volatile fatty acids [VFAs]), domestic and industrial wastewater from a full-scale wastewater treatment facility. The pilot plants were operated at 100, 50, 40, and 25% RAS (percent of available RAS) flows to the anaerobic tank, with the remaining RAS to the anoxic tank. In addition, varying anaerobic HRT (1.08 and 1.5 hours) and increased hydraulic loading (35% increase) were examined. The study was divided into four phases, and the effect of these process variations on EBPR were studied by having one different variable between two identical systems. The most significant conclusion was that returning part of the RAS to the anaerobic zone did not decrease EBPR performance; instead, it changed the location of phosphorous release and uptake. Bringing less RAS to the anaerobic and more to the anoxic tank decreased anaerobic phosphorus release and increased anoxic phosphorus release (or decreased anoxic phosphorus uptake). Equally important is that, with VFA-rich influent wastewater, excessive anaerobic volume was shown to hurt overall phosphorus removal, even when it resulted in increased anaerobic phosphorus release.

  14. Some perspective decisions for the regeneration system equipment of the thermal and nuclear power plants decreasing the probability of water ingress into the turbine and rotor acceleration by return steam flow

    Science.gov (United States)

    Trifonov, N. N.; Svyatkin, F. A.; Sintsova, T. G.; Ukhanova, M. G.; Yesin, S. B.; Nikolayenkova, E. K.; Yurchenko, A. Yu.; Grigorieva, E. B.

    2016-03-01

    The regeneration system heaters are one of the sources of possible ingress of the water into the turbine. The water penetrates into the turbine either at the heaters overflow or with the return flow of steam generated when the water being in the heater boils up in the dynamic operation modes or at deenergization of the power-generating unit. The return flow of steam and water is dangerous to the turbine blades and can result in the rotor acceleration. The known protective devices used to prevent the overflow of the low-pressure and high-pressure heaters (LPH and HPH), of the horizontal and vertical heaters of heating-system water (HWH and VWH), as well as of the deaerators and low-pressure mixing heaters (LPMH) were considered. The main protective methods of the steam and water return flows supplied by the heaters in dynamic operation modes or at deenergization of the power-generating unit are described. Previous operating experience shows that the available protections do not fully prevent water ingress into the turbine and the rotor acceleration and, therefore, the development of measures to decrease the possibility of ingress of the water into the turbine is an actual problem. The measures allowing eliminating or reducing the water mass in the heaters are expounded; some of them were designed by the specialists of OAO Polzunov Scientific and Development Association on Research and Design of Power Equipment (NPO CKTI) and are efficiently introduced at heat power plants and nuclear power plants. The suggested technical solutions allow reducing the possibility of the water ingress into the turbine and rotor acceleration by return steam flow in the dynamic operation modes or in the case of power generating unit deenergization. Some of these solutions have been tested in experimental-industrial exploitation and can be used in industry.

  15. Meridional distribution and seasonal variation of stable oxygen isotope ratio of precipitation in the Southern Ocean

    Directory of Open Access Journals (Sweden)

    Kayo Nakamura

    2010-07-01

    Full Text Available The stable oxygen isotope ratio(δ^O in precipitation is known to have important meridional and seasonal variations, but there are almost no measurements of δ^O in precipitation over polar oceans. The present research took advantage of 4 opportunities for in situ observations in summer and winter at high latitudes in the Southern Ocean. In addition, we analyzed samples of precipitation at Syowa Station in 2008 to obtain year-round data. Based on these data, we consider the meridional and seasonal variations of δ^O in precipitation over the Southern Ocean. In general, δ^O decreases with increasing latitude, and is lower in winter than in summer. The latitude gradient is stronger in winter. At 60°S, δ^O is -5.4‰ and -11.3‰ in summer and winter, respectively, while the corresponding figures at 66°S are -10.5‰ and -20.8‰. These results will help us understand the mechanisms of the salinity distribution and its variation in the Antarctic Ocean.

  16. Risk and return in oilfield asset holdings

    International Nuclear Information System (INIS)

    Kretzschmar, Gavin L.; Kirchner, Axel; Reusch, Hans

    2008-01-01

    Convention suggests that emerging market investment should provide commensurately lower risk or higher returns than comparable assets in developed countries. This study demonstrates that emerging markets contain regulatory specificities that challenge asset valuation model convergence and potentially invert risk return convention. 292 oilfield assets are used to provide evidence that, under upward oil prices, emerging markets are characterized by progressive state participation in oilfield cash flows. Specifically, this work advances the low oil price paradigm of prior oil and gas asset valuation studies and provides evidence that emerging market state participation terms limit the corporate value of globalization for the sector. (author)

  17. Risk and return in oilfield asset holdings

    Energy Technology Data Exchange (ETDEWEB)

    Kretzschmar, Gavin L.; Kirchner, Axel; Reusch, Hans [University of Edinburgh, College of Humanities and Social Sciences, The Management School (United Kingdom)

    2008-11-15

    Convention suggests that emerging market investment should provide commensurately lower risk or higher returns than comparable assets in developed countries. This study demonstrates that emerging markets contain regulatory specificities that challenge asset valuation model convergence and potentially invert risk return convention. 292 oilfield assets are used to provide evidence that, under upward oil prices, emerging markets are characterized by progressive state participation in oilfield cash flows. Specifically, this work advances the low oil price paradigm of prior oil and gas asset valuation studies and provides evidence that emerging market state participation terms limit the corporate value of globalization for the sector. (author)

  18. Meridional overturning circulation conveys fast acidification to the deep Atlantic Ocean

    Science.gov (United States)

    Perez, Fiz F.; Fontela, Marcos; García-Ibáñez, Maribel I.; Mercier, Herlé; Velo, Anton; Lherminier, Pascale; Zunino, Patricia; de La Paz, Mercedes; Alonso-Pérez, Fernando; Guallart, Elisa F.; Padin, Xose A.

    2018-02-01

    Since the Industrial Revolution, the North Atlantic Ocean has been accumulating anthropogenic carbon dioxide (CO2) and experiencing ocean acidification, that is, an increase in the concentration of hydrogen ions (a reduction in pH) and a reduction in the concentration of carbonate ions. The latter causes the ‘aragonite saturation horizon’—below which waters are undersaturated with respect to a particular calcium carbonate, aragonite—to move to shallower depths (to shoal), exposing corals to corrosive waters. Here we use a database analysis to show that the present rate of supply of acidified waters to the deep Atlantic could cause the aragonite saturation horizon to shoal by 1,000-1,700 metres in the subpolar North Atlantic within the next three decades. We find that, during 1991-2016, a decrease in the concentration of carbonate ions in the Irminger Sea caused the aragonite saturation horizon to shoal by about 10-15 metres per year, and the volume of aragonite-saturated waters to reduce concomitantly. Our determination of the transport of the excess of carbonate over aragonite saturation (xc[CO32-])—an indicator of the availability of aragonite to organisms—by the Atlantic meridional overturning circulation shows that the present-day transport of carbonate ions towards the deep ocean is about 44 per cent lower than it was in preindustrial times. We infer that a doubling of atmospheric anthropogenic CO2 levels—which could occur within three decades according to a ‘business-as-usual scenario’ for climate change—could reduce the transport of xc[CO32-] by 64-79 per cent of that in preindustrial times, which could severely endanger cold-water coral habitats. The Atlantic meridional overturning circulation would also export this acidified deep water southwards, spreading corrosive waters to the world ocean.

  19. Axisymmetric vibrations of thick shells of revolution having meridionally varying curvature

    International Nuclear Information System (INIS)

    Suzuki, Katsuyoshi; Kosawada, Tadashi; Takahashi, Shin; Takahashi, Fumiaki.

    1987-01-01

    An exact method using power series expansions is presented for solving axisymmetric free vibration problems for thick shells of revolution having meridionally varying curvature. Based on the improved thick shell theory, the Lagrangian of the shells of revolution are obtained, and the equations of motion and the boundary conditions are derived from the stationary condition of the Lagrangian. The method is applied to thick shells of revolution having their generating curves of ellipse, cycloid, parabola, catenary and hyperbola. The results by the present method are compared with those by the thin shell theory and the effects of rotatory inertia and shear deformation upon the natural frequencies and the mode shapes are clarified. (author)

  20. A proposed through-flow inverse method for the design of mixed-flow pumps

    Science.gov (United States)

    Borges, Joao Eduardo

    1991-01-01

    A through-flow (hub-to-shroud) truly inverse method is proposed and described. It uses an imposition of mean swirl, i.e., radius times mean tangential velocity, given throughout the meridional section of the turbomachine as an initial design specification. In the present implementation, it is assumed that the fluid is inviscid, incompressible, and irrotational at inlet and that the blades are supposed to have zero thickness. Only blade rows that impart to the fluid a constant work along the space are considered. An application of this procedure to design the rotor of a mixed-flow pump is described in detail. The strategy used to find a suitable mean swirl distribution and the other design inputs is also described. The final blade shape and pressure distributions on the blade surface are presented, showing that it is possible to obtain feasible designs using this technique. Another advantage of this technique is the fact that it does not require large amounts of CPU time.

  1. Fuel cell with internal flow control

    Science.gov (United States)

    Haltiner, Jr., Karl J.; Venkiteswaran, Arun [Karnataka, IN

    2012-06-12

    A fuel cell stack is provided with a plurality of fuel cell cassettes where each fuel cell cassette has a fuel cell with an anode and cathode. The fuel cell stack includes an anode supply chimney for supplying fuel to the anode of each fuel cell cassette, an anode return chimney for removing anode exhaust from the anode of each fuel cell cassette, a cathode supply chimney for supplying oxidant to the cathode of each fuel cell cassette, and a cathode return chimney for removing cathode exhaust from the cathode of each fuel cell cassette. A first fuel cell cassette includes a flow control member disposed between the anode supply chimney and the anode return chimney or between the cathode supply chimney and the cathode return chimney such that the flow control member provides a flow restriction different from at least one other fuel cell cassettes.

  2. Changes in extreme regional sea surface height due to an abrupt weakening of the Atlantic meridional overturning circulation

    NARCIS (Netherlands)

    Brunnabend, S.-E.; Dijkstra, H. A.; Kliphuis, M. A.; van Werkhoven, B.J.C.; Bal, H. E.; Seinstra, F.; Maassen, J.; van Meersbergen, M.

    2014-01-01

    As an extreme scenario of dynamical sea level changes, regional sea surface height (SSH) changes that occur in the North Atlantic due to an abrupt weakening of the Atlantic meridional overturning circulation (AMOC) are simulated. Two versions of the same ocean-only model are used to study the effect

  3. Project subsidized by the Sunshine Project in fiscal 1982. Report on achievements in the project commissioned from NEDO - research and development on return of low-temperature hot water (simulated return test and a demonstration return test); 1982 nendo teion nessui kangen ni kansuru kenkyu kaihatsu seika hokokusho. Kangen mogi shiken kangen jissho shiken

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1983-03-01

    Tests and researches were performed with an objective to elucidate a decaying mechanism of return wells when low-temperature hot water utilized for geothermal binary power generation is returned underground. This paper reports the achievements in fiscal 1982. For the simulated return testing equipment, the hot water supply line was changed, a supply line was newly installed for a water flowing test on hot water in the Hacchobara area, flow rate measuring lines for each system were newly installed, and the pressure detecting locations were changed. In the fundamental tests on the simulated return test, experimental researches were carried out on the following items: production of silica scale from geothermal water, solubility of silica acid, effect of pH on polymerization of silica acid, induction time in the polymerization process of silica acid, sizes of poly-silica acid particles in geothermal water, production of poly-silica acid due to temperature drop, oversaturation degree of mono-silica acid, and scale deposition. In the simulated return test, temperature of a simulated column reproducing the return ground bed, particle sizes, and hot water properties were used as the parameters for the test conducted. As a result, the decay in return wells was estimated to be governed predominantly by chemical deposition of the scales. (NEDO)

  4. A Numerical Study on the Improvement of Suction Performance and Hydraulic Efficiency for a Mixed-Flow Pump Impeller

    Directory of Open Access Journals (Sweden)

    Sung Kim

    2014-01-01

    Full Text Available This paper describes a numerical study on the improvement of suction performance and hydraulic efficiency of a mixed-flow pump by impellers. The design of these impellers was optimized using a commercial CFD (computational fluid dynamics code and DOE (design of experiments. The design variables of meridional plane and vane plane development were defined for impeller design. In DOE, variables of inlet part were selected as main design variables in meridional plane, and incidence angle was selected in vane plane development. The verification of the experiment sets that were generated by 2k factorial was done by numerical analysis. The objective functions were defined as the NPSHre (net positive suction head required, total efficiency, and total head of the impellers. The importance of the geometric design variables was analyzed using 2k factorial designs. The interaction between the NPSHre and total efficiency, according to the meridional plane and incidence angle, was discussed by analyzing the 2k factorial design results. The performance of optimally designed model was verified by experiments and numerical analysis and the reliability of the model was retained by comparison of numerical analysis and comparative analysis with the reference model.

  5. Puerto Rican Migration: The Return Flow = La Migracion Puertorriquena: El Reflujo a la Isla.

    Science.gov (United States)

    Vivo, Paquita, Comp.

    This is a guide to materials and research on Puerto Ricans who have returned to Puerto Rico after living in the United States. Part 1 is an annotated bibliography of books, journal articles, printed documents, doctoral dissertations, master's theses, journalistic accounts, and unpublished papers on characteristics of Puerto Rican return migrants;…

  6. DAMPAK PENYAJIAN KEMBALI EPS DAN CFPS TERHADAP RETURN SAHAM

    Directory of Open Access Journals (Sweden)

    Imelda Sinaga

    2014-04-01

    Full Text Available The problem in this study is whether there is a positive influence of CFPS and EPS before and after restatement in giving positive impact on stock returns. The sample used in EPS before and after the restatement, while as many as 102 samples meanwhile CFPS before and after restatement using 82 sample companies listed on the Stock Exchange. Independent variables used in this study are the earnings per share and cash flow per share and the dependent variables used in this study is the stock return. Test equipment used in this study using multiple regression statistical model           The results of this study demonstrate that EPS before restatement did not impact significantly on the stock returns which indicates that investors have been aware that there is signal to improve the EPS before the restatement. EPS after restatement had no significant effect on return, this indicates that the new information is in accordance with the Market Efficiency hypothesis is that will make the market participants to react and take action to respond that new information. CFPS before and after restatement also had no significant effect on stock returns because investors do not use operating cash flow information as a basic for investment decisions. This can have implications on investors who use financial statements to make right decisions on the location of their assets in the companies that perform restatement as well for the company itself that financial report restatement can be made if it is seen as a form of commitment and sense of responsibility to the market to provide trustable information

  7. Analisis Pengaruh Perubahan Arus Kas dan Laba Akuntansi Terhadap Return Saham pada Perusahaan Berkapitalisasi Besar

    Directory of Open Access Journals (Sweden)

    Azilia Yocelyn

    2012-01-01

    Full Text Available This study aims to examine whether the changes of cash flows and accounting profit, used by investors to make investment decision, reflected in the companies’ stock return. There are four independent variables includes in this study, that is cash flows from operating, investing, and financing activities, as well as accounting profit. The stock return is calculated by using the geometric mean method. Multiple regression analysis is used to examine the data on the top 97 public companies (based on market capitalization catagory listed in Indonesia Stock Exchange for period 2009-2010. The result reveals that accounting profit disclosure markedly affected the stock return. This implies that investors took into account the publication of accounting profit in their decision making. On the other side, the study cannot prove the association of other independent variables to  the stock return.

  8. Impacts of the Pacific Meridional Mode on Landfalling North Atlantic tropical cyclones

    Science.gov (United States)

    Zhang, Wei; Villarini, Gabriele; Vecchi, Gabriel A.; Murakami, Hiroyuki

    2018-02-01

    This study examines the impacts of the Pacific Meridional Mode (PMM) on North Atlantic tropical cyclones (TCs) making landfall along the coastal US, Caribbean Islands and Mexico, and provides insights on the underlying physical mechanisms using observations and model simulations. There is a statistically significant time-lagged association between spring PMM and the August-October US and Caribbean landfalling TCs. Specifically, the positive (negative) spring PMM events tend to be followed by fewer (more) TCs affecting the coastal US (especially over the Gulf of Mexico and Florida) and the Caribbean Islands. This lagged association is mainly caused by the lagged impacts of PMM on the El Niño Southern Oscillation (ENSO), and the subsequent impacts of ENSO on TC frequency and landfalls. Positive (negative) PMM events are largely followed by El Niño (La Niña) events, which lead to less (more) TC geneses close to the US coast (i.e., the Gulf of Mexico and the Caribbean Sea); this also leads to easterly (westerly) steering flow in the vicinity of the US and Caribbean coast, which is unfavorable (favorable) to TC landfall across the Gulf of Mexico, Florida and Caribbean Islands. Perturbation simulations with the state-of-the-art Geophysical Fluid Dynamics Laboratory Forecast-oriented Low Ocean Resolution Version of CM2.5 (FLOR) support the linkage between PMM and TC landfall activity. The time-lagged impacts of spring PMM on TC landfalling activity results in a new predictor to forecast seasonal TC landfall activity along the US (especially over the Gulf of Mexico and Florida) and Caribbean coastal regions.

  9. Effect of PEEP, blood volume, and inspiratory hold maneuvers on venous return.

    Science.gov (United States)

    Berger, David; Moller, Per W; Weber, Alberto; Bloch, Andreas; Bloechlinger, Stefan; Haenggi, Matthias; Sondergaard, Soren; Jakob, Stephan M; Magder, Sheldon; Takala, Jukka

    2016-09-01

    According to Guyton's model of circulation, mean systemic filling pressure (MSFP), right atrial pressure (RAP), and resistance to venous return (RVR) determine venous return. MSFP has been estimated from inspiratory hold-induced changes in RAP and blood flow. We studied the effect of positive end-expiratory pressure (PEEP) and blood volume on venous return and MSFP in pigs. MSFP was measured by balloon occlusion of the right atrium (MSFPRAO), and the MSFP obtained via extrapolation of pressure-flow relationships with airway occlusion (MSFPinsp_hold) was extrapolated from RAP/pulmonary artery flow (QPA) relationships during inspiratory holds at PEEP 5 and 10 cmH2O, after bleeding, and in hypervolemia. MSFPRAO increased with PEEP [PEEP 5, 12.9 (SD 2.5) mmHg; PEEP 10, 14.0 (SD 2.6) mmHg, P = 0.002] without change in QPA [2.75 (SD 0.43) vs. 2.56 (SD 0.45) l/min, P = 0.094]. MSFPRAO decreased after bleeding and increased in hypervolemia [10.8 (SD 2.2) and 16.4 (SD 3.0) mmHg, respectively, P waterfall. Copyright © 2016 the American Physiological Society.

  10. CFD study of leakage flows in shroud cavities of a compressor impeller

    Science.gov (United States)

    Soldatova, K.

    2017-08-01

    The flow character in a gap between shroud disc of an impeller and a stator surface (shroud cavity) influences disc friction loss, labyrinth seal loss (parasitic losses) and thrust force. Flow calculations inside the shroud cavity of a model of centrifugal compressor stage and its labyrinth seal in a range of flow rates and axial width and radial gap are presented. The results are presented in terms of non-dimensional coefficients of flow, disc friction and seal leakage losses coefficients and pressure coefficient. The distributions meridional and tangential flow velocities correspond to the continuity and equilibrium equations - flow radial circulation exists in wide cavity and is absent in narrow cavities. The radial pressure distributions as measured and calculated are not fully comparable. The possible reason is that CFD-calculated leakage coefficient is less than calculated by A.Stodola formula. The influence of a cavity width on the losses and the thrust force requires a balanced design.

  11. A prediction of 3-D viscous flow and performance of the NASA Low-Speed Centrifugal Compressor

    Science.gov (United States)

    Moore, John; Moore, Joan G.

    1990-01-01

    A prediction of the three-dimensional turbulent flow in the NASA Low-Speed Centrifugal Compressor Impeller has been made. The calculation was made for the compressor design conditions with the specified uniform tip clearance gap. The predicted performance is significantly worse than that predicted in the NASA design study. This is explained by the high tip leakage flow in the present calculation and by the different model adopted for tip leakage flow mixing. The calculation gives an accumulation of high losses in the shroud/pressure-side quadrant near the exit of the impeller. It also predicts a region of meridional backflow near the shroud wall. Both of these flow features should be extensive enough in the NASA impeller to allow detailed flow measurements, leading to improved flow modeling. Recommendations are made for future flow studies in the NASA impeller.

  12. Control-Flow Analysis of Function Calls and Returns by Abstract Interpretation

    DEFF Research Database (Denmark)

    Midtgaard, Jan; Jensen, Thomas P.

    , effectively approximating where function calls return across optimized tail calls. The analysis is systematically calculated by abstract interpretation of the stack-based CaEK abstract machine of Flanagan et al. using a series of Galois connections. Abstract interpretation provides a unifying setting in which...

  13. Geomagnetic storm effects in ionospheric TEC at an euatorial station: contribution of EXB drifts and meridional neutral winds

    International Nuclear Information System (INIS)

    Dabas, R.S.; Jain, A.R.

    1985-01-01

    Storm-time variations in TEC measurements at the Indian station Ootacamund with IEC data for four stations in the anomaly region. Variations in Nsub(T)(OOTY) are found to be smaller compared to those observed at anomaly stations. The equatorial electrojet control of Nsub(T)(OOTY) is weaker compared to that of Nsub(m)F2. This result and absence of midday biteout in Nsub(T)(OOTY) are interpreted in terms of plasma exchange between ionosphere and plasmasphere which, to some extent, compensates the loss of plasma in the column due to E x B drifts. The anomaly depth is found to be well correlated with the electrojet strength. It is also noticed that for the same anomaly is weaker on a storm day than for quiet days. This is interpreted in terms of converging equatorward meridional winds. Thus, ionosphere-plasmasphere plasma exchange and, during disturbed period, the converging equatorward meridional winds also have significant effects on the distribution of ionization at these latitudes though the E x B drifts are most important in affecting the ionization distribution at low latitudes. (author)

  14. Vibrations of laminated composite thick shells of revolution having meridionally varying curvature

    International Nuclear Information System (INIS)

    Suzuki, Katsuyoshi; Shikanai, Genji; Baba, Iwato

    1998-01-01

    An exact solution is presented for solving free vibrations of laminated composite thick shells of revolution having meridionally varying curvature. Based on the thick lamination theory considering the shear deformation and rotary inertia, equations of motion and boundary conditions are obtained from the stationary conditions of the Lagrangian. The equations of motion are solved exactly by using a power series expansion for symmetrically laminated cross-ply shells. Frequencies and mode shapes of shells of revolution having elliptical and parabolical meridians are presented for both ends clamped, and the effects of shear deformation and rotary inertia are discussed by comparing the results from the present theory with those from the thin lamination theory. (author)

  15. Comparison of high-latitude thermospheric meridional winds I: optical and radar experimental comparisons

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, E.M.; Mueller-Wodarg, I.C.F.; Aruliah, A.; Aylward, A. [Atmospheric Physics Lab., Univ. Coll. London, London (United Kingdom)

    2004-07-01

    Thermospheric neutral winds at Kiruna, Sweden (67.4 N, 20.4 E) are compared using both direct optical fabry-perot interferometer (FPI) measurements and those derived from European incoherent scatter radar (EISCAT) measurements. This combination of experimental data sets, both covering well over a solar cycle of data, allows for a unique comparison of the thermospheric meridional component of the neutral wind as observed by different experimental techniques. Uniquely in this study the EISCAT measurements are used to provide winds for comparison using two separate techniques: the most popular method based on the work of Salah and Holt (1974) and the meridional wind model (MWM) (Miller et al., 1997) application of servo theory. The balance of forces at this location that produces the observed diurnal pattern are investigated using output from the coupled thermosphere and ionosphere (CTIM) numerical model. Along with detailed comparisons from short periods the climatological behaviour of the winds have been investigated for seasonal and solar cycle dependence using the experimental techniques. While there are features which are consistent between the 3 techniques, such as the evidence of the equinoctial asymmetry, there are also significant differences between the techniques both in terms of trends and absolute values. It is clear from this and previous studies that the high-latitude representation of the thermospheric neutral winds from the empirical horizontal wind model (HWM), though improved from earlier versions, lacks accuracy in many conditions. The relative merits of each technique are discussed and while none of the techniques provides the perfect data set to address model performance at high-latitude, one or more needs to be included in future HWM reformulations. (orig.)

  16. Some studies of zonal and meridional wind characteristics at low latitude Indian stations

    Science.gov (United States)

    Nagpal, O. P.; Kumar, S.

    1985-12-01

    At the beginning of the Indian Middle Atmosphere Programme (IMAP), it was decided that the preparation of consolidation reports of already available parameters for the middle atmosphere would be useful. Atmospheric wind data obtained by rockets and balloons constituted one such parameter which had to be consolidated. The present paper summaries the results of this consolidation study. Both zonal and meridional components of winds at four low latitude Indian stations namely Thumba, Shar, Hyderabad, and Balasore, have been analyzed to yield reference wind profiles for each month. The montly mean values have been used to bring out the amplitudes and phases of the annual, semiannual and quasi-biennial oscillations.

  17. Some studies of zonal and meridional wind characteristics at low latitude Indian stations

    Science.gov (United States)

    Nagpal, O. P.; Kumar, S.

    1985-01-01

    At the beginning of the Indian Middle Atmosphere Programme (IMAP), it was decided that the preparation of consolidation reports of already available parameters for the middle atmosphere would be useful. Atmospheric wind data obtained by rockets and balloons constituted one such parameter which had to be consolidated. The present paper summaries the results of this consolidation study. Both zonal and meridional components of winds at four low latitude Indian stations namely Thumba, Shar, Hyderabad, and Balasore, have been analyzed to yield reference wind profiles for each month. The montly mean values have been used to bring out the amplitudes and phases of the annual, semiannual and quasi-biennial oscillations.

  18. Pricing and Hedging Guaranteed Returns on Mix Funds

    NARCIS (Netherlands)

    Vellekoop, M.H.; van de Kamp, A.A.; Post, B.A.

    2006-01-01

    Abstract In this paper we propose a valuation and hedging strategy for a guaranteed minimal rate of return on a mix fund, which participates in both bonds and stocks. For the case where a fixed amount of money is invested, we show that a European put option on the mix fund replicates the cash flows

  19. GOOD NEWS, BAD NEWS AND GARCH EFFECTS IN STOCK RETURN DATA

    OpenAIRE

    Craig A. Depken II

    2001-01-01

    It is shown that the volume of trade can be decomposed into proportional proxies for stochastic flows of good news and bad news into the market. Positive (good) information flows are assumed to increase the price of a financial vehicle while negative (bad) information flows decrease the price. For the majority of a sample of ten split-stocks it is shown that the proposed decomposition explains more GARCH than volume itself. Using the proposed decomposition, the variance of returns for younger...

  20. Stationary spiral flow in polytropic stellar models

    Science.gov (United States)

    Pekeris, C. L.

    1980-01-01

    It is shown that, in addition to the static Emden solution, a self-gravitating polytropic gas has a dynamic option in which there is stationary flow along spiral trajectories wound around the surfaces of concentric tori. The motion is obtained as a solution of a partial differential equation which is satisfied by the meridional stream function, coupled with Poisson's equation and a Bernoulli-type equation for the pressure (density). The pressure is affected by the whole of the Bernoulli term rather than by the centrifugal part only, which acts for a rotating model, and it may be reduced down to zero at the center. The spiral type of flow is illustrated for an incompressible fluid (n = 0), for which an exact solution is obtained. The features of the dynamic constant-density model are discussed as a basis for future comparison with the solution for compressible models. PMID:16592825

  1. An Efficient Return Algorithm for Non-Associated Mohr-Coulomb Plasticity

    DEFF Research Database (Denmark)

    Clausen, Johan Christian; Damkilde, Lars; Andersen, Lars

    2005-01-01

    . The stress return and the formation of the constitutive matrix is carried out in principal stress space, where the manipulations simplify and rely on geometrical arguments. The singularities arising at the intersection of yield planes are dealt with in a straightforward way also based on geometric......An efficient return algorithm for stress update in numerical plasticity computations is presented. The yield criterion must be linear in principal stress space, and can be composed of any number of yield planes. Each of these yield planes can have an associated or non-associated flow rule...

  2. Características clínicas da doença diarréica em lactentes na Zona da Mata Meridional do estado de Pernambuco Clinical characteristics of diarrheal disease in suckling children in the Zona da Mata Meridional in the State of Pernambuco

    Directory of Open Access Journals (Sweden)

    Giselia Alves Pontes da Silva

    2002-12-01

    Full Text Available OBJETIVOS: descrever as características clínicas dos episódios diarréicos apresentados por um grupo de crianças residentes na Zona da Mata Meridional do estado de Pernambuco nos primeiros seis meses de vida. MÉTODOS: o desenho do estudo é uma série de casos dele fazem parte todas as crianças acompanhadas dentro de um estudo de coorte realizado em quatro cidades da Zona da Mata Meridional do estado de Pernambuco e que durante o período de observação apresentaram pelo menos um episódio de doença diarréica. RESULTADOS: foram acompanhados 264 episódios de doença diarréica, que ocorreram em 239 crianças. A duração dos episódios variou entre um e 31 dias, sendo a mediana de dois dias e a moda de um dia. Um total de 93,5% dos episódios se auto-limitou em até sete dias. A maioria das crianças apresentou um episódio de diarréia durante o período de observação. Houve necessidade de hospitalização em 18 episódios (6,8%. Não foi observado nenhum óbito. CONCLUSÕES: a evolução clínica da doença diarréica quando estudada na comunidade é benigna, com episódios diarréicos de curta duração e levando a baixos índices de hospitalização.OBJECTIVES: to describe clinical characteristics of diarrhea episodes in a group of children residing in the Zona da Mata Meridional in the State of Pernambuco during the first six months of life. METHODS: the study's design is a case series comprising all children followed-up within a cohort study accomplished in four cities of the Zona da Mata Meridional of the State of Pernambuco who during observation had at least one episode of diarrheal disease. RESULTS: 264 episodes of diarrhea were followed-up in 239 children. The episodes lasted between one and 31 days, with the median of two days and the mode of one day. 93,5% of the episodes were self-limited to seven days. The majority of the children had one diarrhea episode during observation. Hospitalization was required in 18 episodes

  3. A multimodel comparison of centennial Atlantic meridional overturning circulation variability

    Energy Technology Data Exchange (ETDEWEB)

    Menary, Matthew B.; Vellinga, Michael; Palmer, Matthew D. [Met Office Hadley Centre, Exeter, Devon (United Kingdom); Park, Wonsun; Latif, Mojib [IFM-GEOMAR, Leibniz-Institut fuer Meereswissenschaften, Kiel (Germany); Lohmann, Katja; Jungclaus, Johann H. [Max Planck Inst Meteorol, Hamburg (Germany)

    2012-06-15

    A mechanism contributing to centennial variability of the Atlantic Meridional Overturning Circulation (AMOC) is tested with multi-millennial control simulations of several coupled general circulation models (CGCMs). These are a substantially extended integration of the 3rd Hadley Centre Coupled Climate Model (HadCM3), the Kiel Climate Model (KCM), and the Max Plank Institute Earth System Model (MPI-ESM). Significant AMOC variability on time scales of around 100 years is simulated in these models. The centennial mechanism links changes in the strength of the AMOC with oceanic salinities and surface temperatures, and atmospheric phenomena such as the Intertropical Convergence Zone (ITCZ). 2 of the 3 models reproduce all aspects of the mechanism, with the third (MPI-ESM) reproducing most of them. A comparison with a high resolution paleo-proxy for Sea Surface Temperatures (SSTs) north of Iceland over the last 4,000 years, also linked to the ITCZ, suggests that elements of this mechanism may also be detectable in the real world. (orig.)

  4. Meridional Modes and Increasing Pacific Decadal Variability Under Anthropogenic Forcing

    Science.gov (United States)

    Liguori, Giovanni; Di Lorenzo, Emanuele

    2018-01-01

    Pacific decadal variability has strong impacts on the statistics of weather, atmosphere extremes, droughts, hurricanes, marine heatwaves, and marine ecosystems. Sea surface temperature (SST) observations show that the variance of the El Niño-like decadal variability has increased by 30% (1920-2015) with a stronger coupling between the major Pacific climate modes. Although we cannot attribute these trends to global climate change, the examination of 30 members of the Community Earth System Model Large Ensemble (LENS) forced with the RCP8.5 radiative forcing scenario (1920-2100) suggests that significant anthropogenic trends in Pacific decadal variance will emerge by 2020 in response to a more energetic North Pacific Meridional Mode (PMM)—a well-known El Niño precursor. The PMM is a key mechanism for energizing and coupling tropical and extratropical decadal variability. In the LENS, the increase in PMM variance is consistent with an intensification of the winds-evaporation-SST thermodynamic feedback that results from a warmer mean climate.

  5. A Study on the Relationship of Earnings and Cash Flows: Evidence of Finance Sector in Iran

    Directory of Open Access Journals (Sweden)

    Mahdi Salehi

    2013-08-01

    Full Text Available The present study is investigating the quality of annual accounting earnings in banking firms that have been listed in Tehran Stock Exchange (TSE and it evaluates the most important information of accounting that is earnings and cash flows. The study also intends to investigate the relationship between earnings and cash flows regarding their relationship with the expected return of stocks and the extent of informing in the analysis of the inevitable return of stocks. The analyses of data during 6 years revealed that the earnings in comparison to the cash flows are very important as they have positive effects on the stock. Moreover, in the case of the relations of earnings and earnings changes with the expected return of stocks and the relation of cash flows and cash flow changes with the expected return of stock, it was found that there is only a meaningful relationship between earning changes and the expected return of stock in banking groups. However, there is no meaningful relationship between earning and cash flows with the expected return of stock. The result was that the informational content test didn’t support the value relation of earning and cash flows. Furthermore, the classifying of information through banking group indicated that the changes of earning was in the first rank and next were earning, the changes of cash flow and cash flows.Keywords: Earnings; Cash flows; expected return; Value relevance; Banking risks

  6. PENGARUH LABA AKUNTANSI DAN ARUS KAS TERHADAP RETURN SAHAM SYARIAH YANG TERDAFTAR DI JAKARTA ISLAMIC INDEX TAHUN 2007-2008

    Directory of Open Access Journals (Sweden)

    Elvina Widowati

    2013-12-01

    Full Text Available Capital market is a financial institution, where investors can invest their funds in securities. Establishment of the Jakarta Islamic Index is expected to improve investor confidence to develop the investment in the securities of the sharia. The one of investing purpose is to get a return as an advantage. The information of earnings and cash flow may cause investors action toward the company's stock. This study aims to determine the effect of accounting earnings and cash flow toward stock return. The data which used are secondary data such as company’s financial reports and stock prices. The population in this study are stocks listed in the Jakarta Islamic Index 2007-2008. The sample which used in this study are 32 companies. Technique of sampling that is used in this study is purposive sampling method. The data analysis that used is multiple regression analysis. The Regression analysis is used to test the effect of accounting earnings variable and cash flows variable toward stock returns. The analysis results shown that both independent variables have simultaneously influence to the dependent variable, and individually only accounting earnings influence significantly to the stock returns. Meanwhile, the total cash flow does not influence the stock return variable.Based on the results, the suggestion for further research is able to extend the period of observation, using other variables are not described in this study.

  7. The Conceptual Model of Calculating the Return Period of the Costs for Creation of the Enterprise’s Economic Security Service in the Short-Term Period

    Directory of Open Access Journals (Sweden)

    Melikhova Tetiana O.

    2018-03-01

    Full Text Available Determination of the return period of the costs, advanced for the creation of economic security service of enterprise during a year, involves consideration of interaction of the conditional money flow, accumulated for a certain number of months, and the constant costs. The main component of the constant costs are the annual depreciation deductions. The return period is considered as gross, net, valid, and specified. The gross (net, valid, and specified return period is the time, wherein the gross conditional money flow, equal to the advanced costs, will be accumulated. The gross return period, taking account of the effect of time factor, is proposed to be defined as the ratio of annual depreciation deductions increased by the annual compounding coefficient to the conditional average monthly gross money flow, increased by the average monthly inflation index. As for the short-term period, a relationship between the gross, net, valid, and specified return periods of the costs, advanced to the creation of the economic security service, has been identified. The net (valid, specified return period is equal to the gross period adjusted to the coefficient of excess of the gross conditional money flow, accumulated in the gross period, over the net (valid, specified conditional cash flow.

  8. PIV measurements in a compact return diffuser under multi-conditions

    Science.gov (United States)

    Zhou, L.; Lu, W. G.; Shi, W. D.

    2013-12-01

    Due to the complex three-dimensional geometries of impellers and diffusers, their design is a delicate and difficult task. Slight change could lead to significant changes in hydraulic performance and internal flow structure. Conversely, the grasp of the pump's internal flow pattern could benefit from pump design improvement. The internal flow fields in a compact return diffuser have been investigated experimentally under multi-conditions. A special Particle Image Velocimetry (PIV) test rig is designed, and the two-dimensional PIV measurements are successfully conducted in the diffuser mid-plane to capture the complex flow patterns. The analysis of the obtained results has been focused on the flow structure in diffuser, especially under part-load conditions. The vortex and recirculation flow patterns in diffuser are captured and analysed accordingly. Strong flow separation and back flow appeared at the part-load flow rates. Under the design and over-load conditions, the flow fields in diffuser are uniform, and the flow separation and back flow appear at the part-load flow rates, strong back flow is captured at one diffuser passage under 0.2Qdes.

  9. Does δ18O of O2 record meridional shifts in tropical rainfall?

    Science.gov (United States)

    Seltzer, Alan M.; Buizert, Christo; Baggenstos, Daniel; Brook, Edward J.; Ahn, Jinho; Yang, Ji-Woong; Severinghaus, Jeffrey P.

    2017-10-01

    Marine sediments, speleothems, paleo-lake elevations, and ice core methane and δ18O of O2 (δ18Oatm) records provide ample evidence for repeated abrupt meridional shifts in tropical rainfall belts throughout the last glacial cycle. To improve understanding of the impact of abrupt events on the global terrestrial biosphere, we present composite records of δ18Oatm and inferred changes in fractionation by the global terrestrial biosphere (ΔɛLAND) from discrete gas measurements in the WAIS Divide (WD) and Siple Dome (SD) Antarctic ice cores. On the common WD timescale, it is evident that maxima in ΔɛLAND are synchronous with or shortly follow small-amplitude WD CH4 peaks that occur within Heinrich stadials 1, 2, 4, and 5 - periods of low atmospheric CH4 concentrations. These local CH4 maxima have been suggested as markers of abrupt climate responses to Heinrich events. Based on our analysis of the modern seasonal cycle of gross primary productivity (GPP)-weighted δ18O of terrestrial precipitation (the source water for atmospheric O2 production), we propose a simple mechanism by which ΔɛLAND tracks the centroid latitude of terrestrial oxygen production. As intense rainfall and oxygen production migrate northward, ΔɛLAND should decrease due to the underlying meridional gradient in rainfall δ18O. A southward shift should increase ΔɛLAND. Monsoon intensity also influences δ18O of precipitation, and although we cannot determine the relative contributions of the two mechanisms, both act in the same direction. Therefore, we suggest that abrupt increases in ΔɛLAND unambiguously imply a southward shift of tropical rainfall. The exact magnitude of this shift, however, remains under-constrained by ΔɛLAND.

  10. Does δ18O of O2 record meridional shifts in tropical rainfall?

    Directory of Open Access Journals (Sweden)

    A. M. Seltzer

    2017-10-01

    Full Text Available Marine sediments, speleothems, paleo-lake elevations, and ice core methane and δ18O of O2 (δ18Oatm records provide ample evidence for repeated abrupt meridional shifts in tropical rainfall belts throughout the last glacial cycle. To improve understanding of the impact of abrupt events on the global terrestrial biosphere, we present composite records of δ18Oatm and inferred changes in fractionation by the global terrestrial biosphere (ΔεLAND from discrete gas measurements in the WAIS Divide (WD and Siple Dome (SD Antarctic ice cores. On the common WD timescale, it is evident that maxima in ΔεLAND are synchronous with or shortly follow small-amplitude WD CH4 peaks that occur within Heinrich stadials 1, 2, 4, and 5 – periods of low atmospheric CH4 concentrations. These local CH4 maxima have been suggested as markers of abrupt climate responses to Heinrich events. Based on our analysis of the modern seasonal cycle of gross primary productivity (GPP-weighted δ18O of terrestrial precipitation (the source water for atmospheric O2 production, we propose a simple mechanism by which ΔεLAND tracks the centroid latitude of terrestrial oxygen production. As intense rainfall and oxygen production migrate northward, ΔεLAND should decrease due to the underlying meridional gradient in rainfall δ18O. A southward shift should increase ΔεLAND. Monsoon intensity also influences δ18O of precipitation, and although we cannot determine the relative contributions of the two mechanisms, both act in the same direction. Therefore, we suggest that abrupt increases in ΔεLAND unambiguously imply a southward shift of tropical rainfall. The exact magnitude of this shift, however, remains under-constrained by ΔεLAND.

  11. Topology and stability of a water-soybean-oil swirling flow

    Science.gov (United States)

    Carrión, Luis; Herrada, Miguel A.; Shtern, Vladimir N.

    2017-02-01

    This paper reveals and explains the flow topology and instability hidden in an experimental study by Tsai et al. [Tsai et al., Phys. Rev. E 92, 031002(R) (2015)], 10.1103/PhysRevE.92.031002. Water and soybean oil fill a sealed vertical cylindrical container. The rotating top disk induces the meridional circulation and swirl of both fluids. The experiment shows a flattop interface shape and vortex breakdown in the oil flow developing as the rotation strength R eo increases. Our numerical study shows that vortex breakdown occurs in the water flow at R eo=300 and in the oil flow at R eo=941 . As R eo increases, the vortex breakdown cell occupies most of the water domain and approaches the interface at R eo around 600. The rest of the (countercirculating) water separates from the axis as the vortex breakdown cells in the oil and water meet at the interface-axis intersection. This topological transformation of water flow significantly contributes to the development of the flattop shape. It is also shown that the steady axisymmetric flow suffers from shear-layer instability, which emerges in the water domain at R eo=810 .

  12. Unsteady flow over a decelerating rotating sphere

    Science.gov (United States)

    Turkyilmazoglu, M.

    2018-03-01

    Unsteady flow analysis induced by a decelerating rotating sphere is the main concern of this paper. A revolving sphere in a still fluid is supposed to slow down at an angular velocity rate that is inversely proportional to time. The governing partial differential equations of motion are scaled in accordance with the literature, reducing to the well-documented von Kármán equations in the special circumstance near the pole. Both numerical and perturbation approaches are pursued to identify the velocity fields, shear stresses, and suction velocity far above the sphere. It is detected that an induced flow surrounding the sphere acts accordingly to adapt to the motion of the sphere up to some critical unsteadiness parameters at certain latitudes. Afterward, the decay rate of rotation ceases such that the flow at the remaining azimuths starts revolving freely. At a critical unsteadiness parameter corresponding to s = -0.681, the decelerating sphere rotates freely and requires no more torque. At a value of s exactly matching the rotating disk flow at the pole identified in the literature, the entire flow field around the sphere starts revolving faster than the disk itself. Increasing values of -s almost diminish the radial outflow. This results in jet flows in both the latitudinal and meridional directions, concentrated near the wall region. The presented mean flow results will be useful for analyzing the instability features of the flow, whether of a convective or absolute nature.

  13. Operating Cash Flow, Earning Response Coefficient, and Fixed Asset Revaluation: Study on Manufacturing Company

    Directory of Open Access Journals (Sweden)

    Andison Andison

    2017-03-01

    Full Text Available The purpose of this study to determine the effect of operating cash flow to the abnormal return and the effect of operating cash flow to the abnormal return of companies that conduct the revaluation is higher than that of non revaluation which adopted SFAS No. 16 (2012. The analysis used in this study are multiple regression, for the period 2012-2015. The results showed that operating cash flow has no effect on non-sampled companies revaluation, while the sample of firms that perform revaluation proves that operating cash flow has a positive and significant impact on the abnormal return. Moreover, the effect of revaluation policy can strengthen the influence between operating cash flow to the firm abnormal return than non revaluation.DOI: 10.15408/etk.v16i1.4820

  14. Returning Special Education Students to Regular Classrooms: Externalities on Peers’ Outcomes

    DEFF Research Database (Denmark)

    Rangvid, Beatrice Schindler

    Policy reforms to boost full inclusion and conventional return flows send students with special educational needs (SEN) from segregated settings to regular classrooms. Using full population micro data from Denmark, I investigate whether becoming exposed to returning SEN students affects...... on test score gains of moderate size (-0.036 SD), while no significant effect is found in non-reform years. The results are robust to sensitivity checks. The negative exposure effect is significant only for boys, but does not differ by parental education or grade-level....

  15. Cardiac output and regional blood flow following trauma

    International Nuclear Information System (INIS)

    Malik, A.B.; Loegering, D.J.; Saba, T.M.; Kaplan, J.E.

    1978-01-01

    The changes in cardiac output (2), regional blood blow (2r) and regional vascular resistance, and arterial pressure were studied in rats subjected to moderate (LD0) or severe (LD50) traumatic shock. 2 and 2r were determined using microspheres at 15, 60 and 180 min posttrauma. Arterial pressure decreased in both groups at 15 min and recovered by 3 h after sublethal (LD0) trauma, while arterial pressure did not return to control levels after LD50 trauma. 2 decreased in both groups at 15 min and returned to control only in the LD0 trauma group by 3 h. Cerebral, coronary, and hepatic arterial flows and resistances were maintained in both groups. Renal, intestinal, and splenic flows decreased and resistances were maintained in both groups. Renal, intestinal, and splenic flows decreased and resistances increased in both groups by 15 min and returned to control levels by 3 h only in the LD0 trauma group. Total hepatic and hepatic portal flows decreased at 60 min and returned to control levels at 3 h after LD0 trauma, while there was significant depression in these parameters 3 h after LD50 trauma. Therefore, sublethal and severe trauma resulted in early redistribution of flow favoring the coronary, cerebral, and hepatic arterial beds. However, renal, intestinal, splenic, and portal flows remained depressed only in severely traumatized rats, suggesting that continued hypofusion is a factor in the multiple organ failure and death following severe traumatic injury

  16. Synthesis and characterization of meridional isomer of uns-cis-(ethylenediamine-N-N'-di-3-propionato-(S-norleucinatocobalt(III semihydrate

    Directory of Open Access Journals (Sweden)

    SRECKO R. TRIFUNOVIC

    2000-07-01

    Full Text Available The meridional geometrical isomer of uns-cis-(ethylenediamine-N-N'-di-3-propionato(S-norleucinatocobalt(III complex has been prepared by the reaction of sodium uns-cis-(ethylenediamine-N-N'-di-3-propionato(carbonatocobaltate(III with S-norleucine at 75°C. The complex was isolated choromatographically and characterized by elemental analyses, electron absorption and infrared spectroscopy.

  17. The relation between AMOC, gyre circulation, and meridional heat transports in the North Atlantic in model simulations of the last millennium

    Science.gov (United States)

    Jungclaus, Johann; Moreno-Chamarro, Eduardo; Lohmann, Katja

    2016-04-01

    While it is clear that the Atlantic Meridional Overturning Circulation (AMOC) is responsible for meridional heat transfer from the South Atlantic and the tropics to the North Atlantic, the majority of the heat transport in the northern North Atlantic and the Nordic seas is carried by the gyre system. However, the detailed mechanisms determining the interaction between and the temporal modulation of the components of the northward heat transport system are not clear. Long-term climate records and model simulations can help to identify important processes and to provide background for the changes that are presently observed. Multi-centennial proxy records from the subpolar North Atlantic and the Nordic Seas indicate, for example, an out-of-phase behavior of sea surface temperature and gyre circulation between the two regions with consequences for regional climate. Paleoceanographic evidence from Fram Strait shows a pronounced modulation of heat transfer to the Arctic by the Atlantic Water layer during the last 2000 years and reconstructions from the Subpolar North Atlantic suggest a role of ocean circulation in the transition between the Medieval Climate Anomaly and the Little Ice Age. Here we explore a small ensemble of last millennium simulations, carried out with the Max Planck Institute Earth System Model, and analyze mechanisms connecting the AMOC and gyre circulation and their relation to external forcing. Our results support the important role of the Subpolar Gyre strength and the related meridional mass and temperature fluxes. We find that the modulation of the northward heat transport into the Nordic Seas and the Arctic has pronounced impact on sea-ice distribution, ocean-atmosphere interaction, and the surface climate in Scandinavia and Western Europe.

  18. Investor sentiment, mutual fund flows and its impact on returns and volatility

    NARCIS (Netherlands)

    Lehnert, T.; Müller, A.; Frijns, B.P.M.; Beaumont, R.J.; Daele, M. van

    2008-01-01

    - Purpose – The purpose of this paper is to investigate the impact of individual investor sentiment on the return process and conditional volatility of three main US market indices (Dow Jones Industrial Average, S&P500 and Nasdaq100). Individual investor sentiment is measured by aggregate money

  19. Growth Opportunities, Earnings Permanence and the Valuation of Free Cash Flow

    Directory of Open Access Journals (Sweden)

    Ahsan Habib

    2011-12-01

    Full Text Available This paper examines empirically the effect of firm growth opportunities and earnings quality on the market valuation of free cash flow, defined as the difference between operating cash flows and capital expenditures. Equity valuation theory prescribes that free cash flow should not be associated with stock returns because itdoes not add value. However, free cash flow could become a value-relevant construct in certain contexts. This study considers growth opportunities and transitory earnings as two such contexts and examines the valuation of free cash flow. An accounting-based valuation framework is developed where stock returns are regressed onfree cash flow interacted with growth and earnings quality proxies, after controlling for book values, dividends, and current earnings realisations. Findings reveal that firms with a positive free cash flow and attractive growth opportunities command a valuation premium. Furthermore, free cash flow is found to be positively associatedwith stock returns when earnings are transitory. The results are robust to alternative definitions of both free cash flow and growth opportunities.

  20. Configuration-specific synthesis of the facial and meridional isomers of tris(8-hydroxyquinolinate)aluminum (Alq3).

    Science.gov (United States)

    Katakura, Ryo; Koide, Yoshihiro

    2006-07-24

    Treatment of AlO(OH) with 3 equiv of 8-hydroxyquinolinol in refluxing deionized water provided the meridional and facial isomers of tris(8-hydroxyquinolinate)aluminum (Alq3) with good yields as solid deposits after 1 and 90 h, respectively. X-ray diffraction and solid-state 13C NMR studies revealed that mer-Alq3 is formed in the early stage of the reaction and then gradually converts to fac-Alq3, which is thermodynamically less stable, although no existence of a catalyst substance is implied.

  1. 'Downward control' of the mean meridional circulation and temperature distribution of the polar winter stratosphere

    Science.gov (United States)

    Garcia, Rolando R.; Boville, Byron A.

    1994-01-01

    According to the 'downward control' principle, the extratropical mean vertical velocity on a given pressure level is approximately proportional to the meridional gradient of the vertically integrated zonal force per unit mass exerted by waves above that level. In this paper, a simple numerical model that includes parameterizations of both planetary and gravity wave breaking is used to explore the influence of gravity wave breaking in the mesosphere on the mean meridional circulation and temperature distribution at lower levels in the polar winter stratosphere. The results of these calculations suggest that gravity wave drag in the mesosphere can affect the state of the polar winter stratosphere down to altitudes below 30 km. The effect is most important when planetary wave driving is relatively weak: that is, during southern winter and in early northern winter. In southern winter, downwelling weakens by a factor of 2 near the stratospause and by 20% at 30 km when gravity wave drag is not included in the calculations. As a consequence, temperatures decrease considerably throughout the polar winter stratosphere (over 20 K above 40 km and as much as 8 K at 30 km, where the effect is enhanced by the long radiative relaxation timescale). The polar winter states obtained when gravity wave drag is omitted in this simple model resemble the results of simulations with some general circulation models and suggest that some of the shortcomings of the latter may be due to a deficit in mesospheric momentum deposition by small-scale gravity waves.

  2. Abyssal ocean overturning shaped by seafloor distribution

    Science.gov (United States)

    de Lavergne, C.; Madec, G.; Roquet, F.; Holmes, R. M.; McDougall, T. J.

    2017-11-01

    The abyssal ocean is broadly characterized by northward flow of the densest waters and southward flow of less-dense waters above them. Understanding what controls the strength and structure of these interhemispheric flows—referred to as the abyssal overturning circulation—is key to quantifying the ocean’s ability to store carbon and heat on timescales exceeding a century. Here we show that, north of 32° S, the depth distribution of the seafloor compels dense southern-origin waters to flow northward below a depth of about 4 kilometres and to return southward predominantly at depths greater than 2.5 kilometres. Unless ventilated from the north, the overlying mid-depths (1 to 2.5 kilometres deep) host comparatively weak mean meridional flow. Backed by analysis of historical radiocarbon measurements, the findings imply that the geometry of the Pacific, Indian and Atlantic basins places a major external constraint on the overturning structure.

  3. PIV measurements in a compact return diffuser under multi-conditions

    International Nuclear Information System (INIS)

    Zhou, L; Lu, W G; Shi, W D

    2013-01-01

    Due to the complex three-dimensional geometries of impellers and diffusers, their design is a delicate and difficult task. Slight change could lead to significant changes in hydraulic performance and internal flow structure. Conversely, the grasp of the pump's internal flow pattern could benefit from pump design improvement. The internal flow fields in a compact return diffuser have been investigated experimentally under multi-conditions. A special Particle Image Velocimetry (PIV) test rig is designed, and the two-dimensional PIV measurements are successfully conducted in the diffuser mid-plane to capture the complex flow patterns. The analysis of the obtained results has been focused on the flow structure in diffuser, especially under part-load conditions. The vortex and recirculation flow patterns in diffuser are captured and analysed accordingly. Strong flow separation and back flow appeared at the part-load flow rates. Under the design and over-load conditions, the flow fields in diffuser are uniform, and the flow separation and back flow appear at the part-load flow rates, strong back flow is captured at one diffuser passage under 0.2Q des

  4. On the seasonal variability of the Canary Current and the Atlantic Meridional Overturning Circulation

    Science.gov (United States)

    Vélez-Belchí, Pedro; Pérez-Hernández, M. Dolores; Casanova-Masjoan, María.; Cana, Luis; Hernández-Guerra, Alonso

    2017-06-01

    The Atlantic Meridional Overturning Circulation (AMOC) is continually monitored along 26°N by the RAPID-MOCHA array. Measurements from this array show a 6.7 Sv seasonal cycle for the AMOC, with a 5.9 Sv contribution from the upper mid-ocean. Recent studies argue that the dynamics of the eastern Atlantic is the main driver for this seasonal cycle; specifically, Rossby waves excited south of the Canary Islands. Using inverse modeling, hydrographic, mooring, and altimetry data, we describe the seasonal cycle of the ocean mass transport around the Canary Islands and at the eastern boundary, under the influence of the African slope, where eastern component of the RAPID-MOCHA array is situated. We find a seasonal cycle of -4.1 ± 0.5 Sv for the oceanic region of the Canary Current, and +3.7 ± 0.4 Sv at the eastern boundary. This seasonal cycle along the eastern boundary is in agreement with the seasonal cycle of the AMOC that requires the lowest contribution to the transport in the upper mid-ocean to occur in fall. However, we demonstrate that the linear Rossby wave model used previously to explain the seasonal cycle of the AMOC is not robust, since it is extremely sensitive to the choice of the zonal range of the wind stress curl and produces the same results with a Rossby wave speed of zero. We demonstrate that the seasonal cycle of the eastern boundary is due to the recirculation of the Canary Current and to the seasonal cycle of the poleward flow that characterizes the eastern boundaries of the oceans.

  5. Endogenous Information, Risk Characterization, and the Predictability of Average Stock Returns

    Directory of Open Access Journals (Sweden)

    Pradosh Simlai

    2012-09-01

    Full Text Available In this paper we provide a new type of risk characterization of the predictability of two widely known abnormal patterns in average stock returns: momentum and reversal. The purpose is to illustrate the relative importance of common risk factors and endogenous information. Our results demonstrates that in the presence of zero-investment factors, spreads in average momentum and reversal returns correspond to spreads in the slopes of the endogenous information. The empirical findings support the view that various classes of firms react differently to volatility risk, and endogenous information harbor important sources of potential risk loadings. Taken together, our results suggest that returns are influenced by random endogenous information flow, which is asymmetric in nature, and can be used as a performance attribution factor. If one fails to incorporate the existing asymmetric endogenous information hidden in the historical behavior, any attempt to explore average stock return predictability will be subject to an unquantified specification bias.

  6. An analysis of river bank slope and unsaturated flow effects on bank storage.

    Science.gov (United States)

    Doble, Rebecca; Brunner, Philip; McCallum, James; Cook, Peter G

    2012-01-01

    Recognizing the underlying mechanisms of bank storage and return flow is important for understanding streamflow hydrographs. Analytical models have been widely used to estimate the impacts of bank storage, but are often based on assumptions of conditions that are rarely found in the field, such as vertical river banks and saturated flow. Numerical simulations of bank storage and return flow in river-aquifer cross sections with vertical and sloping banks were undertaken using a fully-coupled, surface-subsurface flow model. Sloping river banks were found to increase the bank infiltration rates by 98% and storage volume by 40% for a bank slope of 3.4° from horizontal, and for a slope of 8.5°, delay bank return flow by more than four times compared with vertical river banks and saturated flow. The results suggested that conventional analytical approximations cannot adequately be used to quantify bank storage when bank slope is less than 60° from horizontal. Additionally, in the unconfined aquifers modeled, the analytical solutions did not accurately model bank storage and return flow even in rivers with vertical banks due to a violation of the dupuit assumption. Bank storage and return flow were also modeled for more realistic cross sections and river hydrograph from the Fitzroy River, Western Australia, to indicate the importance of accurately modeling sloping river banks at a field scale. Following a single wet season flood event of 12 m, results showed that it may take over 3.5 years for 50% of the bank storage volume to return to the river. © 2011, The Author(s). Ground Water © 2011, National Ground Water Association.

  7. Support of Publication Costs, Atlantic Meridional Overturning Circulation Special Issue of Deep Sea Research II Journal

    Energy Technology Data Exchange (ETDEWEB)

    Amy Honchar

    2012-11-12

    The contribution of funds from DOE supported publication costs of a special issue of Deep Sea Research arising from presentations at the First U.S. Atlantic Meridional Overturning Circulation (AMOC) Meeting held 4-6 May, 2009 to review the US implementation plan and its coordination with other monitoring activities. The special issue includes a total of 16 papers, including publications from three DOE-supported investigators (ie Sevellec, F., and A.V. Fedorov; Hu et. al., and Wan et. al.,). The special issue addresses DOE interests in understanding and simulation/modeling of abrupt climate change.

  8. North Atlantic observations sharpen meridional overturning projections

    Science.gov (United States)

    Olson, R.; An, S.-I.; Fan, Y.; Evans, J. P.; Caesar, L.

    2018-06-01

    Atlantic Meridional Overturning Circulation (AMOC) projections are uncertain due to both model errors, as well as internal climate variability. An AMOC slowdown projected by many climate models is likely to have considerable effects on many aspects of global and North Atlantic climate. Previous studies to make probabilistic AMOC projections have broken new ground. However, they do not drift-correct or cross-validate the projections, and do not fully account for internal variability. Furthermore, they consider a limited subset of models, and ignore the skill of models at representing the temporal North Atlantic dynamics. We improve on previous work by applying Bayesian Model Averaging to weight 13 Coupled Model Intercomparison Project phase 5 models by their skill at modeling the AMOC strength, and its temporal dynamics, as approximated by the northern North-Atlantic temperature-based AMOC Index. We make drift-corrected projections accounting for structural model errors, and for the internal variability. Cross-validation experiments give approximately correct empirical coverage probabilities, which validates our method. Our results present more evidence that AMOC likely already started slowing down. While weighting considerably moderates and sharpens our projections, our results are at low end of previously published estimates. We project mean AMOC changes between periods 1960-1999 and 2060-2099 of -4.0 Sv and -6.8 Sv for RCP4.5 and RCP8.5 emissions scenarios respectively. The corresponding average 90% credible intervals for our weighted experiments are [-7.2, -1.2] and [-10.5, -3.7] Sv respectively for the two scenarios.

  9. Reduced interdecadal variability of Atlantic Meridional Overturning Circulation under global warming.

    Science.gov (United States)

    Cheng, Jun; Liu, Zhengyu; Zhang, Shaoqing; Liu, Wei; Dong, Lina; Liu, Peng; Li, Hongli

    2016-03-22

    Interdecadal variability of the Atlantic Meridional Overturning Circulation (AMOC-IV) plays an important role in climate variation and has significant societal impacts. Past climate reconstruction indicates that AMOC-IV has likely undergone significant changes. Despite some previous studies, responses of AMOC-IV to global warming remain unclear, in particular regarding its amplitude and time scale. In this study, we analyze the responses of AMOC-IV under various scenarios of future global warming in multiple models and find that AMOC-IV becomes weaker and shorter with enhanced global warming. From the present climate condition to the strongest future warming scenario, on average, the major period of AMOC-IV is shortened from ∼50 y to ∼20 y, and the amplitude is reduced by ∼60%. These reductions in period and amplitude of AMOC-IV are suggested to be associated with increased oceanic stratification under global warming and, in turn, the speedup of oceanic baroclinic Rossby waves.

  10. Reduced interdecadal variability of Atlantic Meridional Overturning Circulation under global warming

    Science.gov (United States)

    Cheng, Jun; Liu, Zhengyu; Zhang, Shaoqing; Liu, Wei; Dong, Lina; Liu, Peng; Li, Hongli

    2016-01-01

    Interdecadal variability of the Atlantic Meridional Overturning Circulation (AMOC-IV) plays an important role in climate variation and has significant societal impacts. Past climate reconstruction indicates that AMOC-IV has likely undergone significant changes. Despite some previous studies, responses of AMOC-IV to global warming remain unclear, in particular regarding its amplitude and time scale. In this study, we analyze the responses of AMOC-IV under various scenarios of future global warming in multiple models and find that AMOC-IV becomes weaker and shorter with enhanced global warming. From the present climate condition to the strongest future warming scenario, on average, the major period of AMOC-IV is shortened from ∼50 y to ∼20 y, and the amplitude is reduced by ∼60%. These reductions in period and amplitude of AMOC-IV are suggested to be associated with increased oceanic stratification under global warming and, in turn, the speedup of oceanic baroclinic Rossby waves. PMID:26951654

  11. Flow distribution in the accelerator-production-of-tritium target

    International Nuclear Information System (INIS)

    Siebe, D.A.; Spatz, T.L.; Pasamehmetoglu, K.O.; Sherman, M.P.

    1999-01-01

    Achieving nearly uniform flow distributions in the accelerator production of tritium (APT) target structures is an important design objective. Manifold effects tend to cause a nonuniform distribution in flow systems of this type, although nearly even distribution can be achieved. A program of hydraulic experiments is underway to provide a database for validation of calculational methodologies that may be used for analyzing this problem and to evaluate the approach with the most promise for achieving a nearly even flow distribution. Data from the initial three tests are compared to predictions made using four calculational methods. The data show that optimizing the ratio of the supply-to-return-manifold areas can produce an almost even flow distribution in the APT ladder assemblies. The calculations compare well with the data for ratios of the supply-to-return-manifold areas spanning the optimum value. Thus, the results to date show that a nearly uniform flow distribution can be achieved by carefully sizing the supply and return manifolds and that the calculational methods available are adequate for predicting the distributions through a range of conditions

  12. Subdifferential-based implicit return-mapping operators in computational plasticity

    Czech Academy of Sciences Publication Activity Database

    Sysala, Stanislav; Čermák, Martin; Koudelka, T.; Kruis, J.; Zeman, J.; Blaheta, Radim

    2016-01-01

    Roč. 96, č. 11 (2016), s. 1318-1338 ISSN 1521-4001 R&D Projects: GA MŠk LQ1602; GA ČR GA13-18652S Institutional support: RVO:68145535 Keywords : elastoplasticity * nonsmooth yield surface * multivalued flow direction * implicit return-mapping scheme * semismooth Newton method * limit analysis Subject RIV: BA - General Mathematics http://onlinelibrary.wiley.com/doi/10.1002/zamm.201500305/full

  13. Managing Returnable Containers Logistics - A Case Study Part II - Improving Visibility through Using Automatic Identification Technologies

    Directory of Open Access Journals (Sweden)

    Gretchen Meiser

    2011-05-01

    Full Text Available This case study is the result of a project conducted on behalf of a company that uses its own returnable containers to transport purchased parts from suppliers. The objective of this project was to develop a proposal to enable the company to more effectively track and manage its returnable containers. The research activities in support of this project included (1 the analysis and documentation of the physical flow and the information flow associated with the containers and (2 the investigation of new technologies to improve the automatic identification and tracking of containers. This paper explains the automatic identification technologies and important criteria for selection. A companion paper details the flow of information and containers within the logistics chain, and it identifies areas for improving the management of the containers.

  14. Dividend growth, cash flow, and discount rate news

    OpenAIRE

    Garrett, Ian; Priestley, Richard

    2012-01-01

    This is the authors’ accepted and refereed manuscript to the article. Publishers web site http://journals.cambridge.org/ Using a new variable based on a model of dividend smoothing, we find that dividend growth is highly predictable and that cash flow news contributes importantly to return variability. Cash flow betas derived from this predictability are central to explaining the size effect in the cross section of returns. However, they do not explain the value effect; this is explained b...

  15. Poland’s Return To Europe: Polish Terrestrial Broadcasters And TV Fiction

    Directory of Open Access Journals (Sweden)

    Sylwia Szostak

    2012-11-01

    Full Text Available The changing political sphere in 1989 and the subsequent 2004 European Union accession had a profound impact on Poland’s economic, political and social spheres. Both events are considered to have marked Poland’s ‘return to Europe’ and strengthened the relations with its Western neighbours. This article examines the changing patterns of television fiction programming flow in Poland in the post-Soviet era, exploring the impact of those two events on Poland’s audiovisual sector. This article therefore assesses whether, and if so – how, this metaphorical ‘return to Europe’ is manifested on Polish television screens.

  16. Population age structure and asset returns: an empirical investigation.

    Science.gov (United States)

    Poterba, J M

    1998-10-01

    "This paper investigates the association between population age structure, particularly the share of the population in the 'prime saving years' 45-60, and the returns on stocks and bonds. The paper is motivated by the claim that the aging of the 'Baby Boom' cohort in the United States is a key factor in explaining the recent rise in asset values. It also addresses the associated claim that asset prices will decline when this large cohort reaches retirement age and begins to reduce its asset holdings. This paper begins by considering household age-asset accumulation profiles. Data from the Survey of Consumer Finances suggest that while cross-sectional age-wealth profiles peak for households in their early 60s, cohort data on the asset ownership of the same households show a much less pronounced peak.... The paper then considers the historical relationship between demographic structure and real returns on Treasury bills, long-term government bonds, and corporate stock. The results do not suggest any robust relationship between demographic structure and asset returns.... The paper concludes by discussing factors such as international capital flows and forward-looking behavior on the part of market participants that could weaken the relationship between age structure and asset returns in a single nation." excerpt

  17. O HORST DA MANTIQUEIRA MERIDIONAL: PROPOSTA DE COMPARTIMENTAÇÃO MORFOESTRUTURAL PARA SUA PORÇÃO MINEIRA

    Directory of Open Access Journals (Sweden)

    Roberto Marques Neto

    2017-08-01

    Full Text Available A Mantiqueira Meridional perfaz o sistema orográfico contínuo mais elevado de todo o Brasil Oriental. Sua gênese está ligada à reativação tectônica que acometeu a Plataforma Brasileira entre o Cretáceo e o Paleógeno orquestrada pela separação da paleoplaca Afro-brasileira e processos geodinâmicos associados, com posteriores reativações vinculadas à dinâmica neotectônica intraplaca e outros efeitos diastróficos oriundos de tectônica ressurgente e ativa. Dessa forma, a compartimentação morfoestrutural da Serra da Mantiqueira integra uma série de feições passivas a um vasto rol de evidências de controle morfotectônico sobrepostos às estruturas preexistentes. O presente artigo consiste numa proposta de compartimentação morfoestrutural para a porção da Mantiqueira Meridional contida no estado de Minas Gerais, enfatizando o controle morfoestrutural, o papel dos níveis de base regionais, e as estruturas tectônicas ativas afetando os diferentes compartimentos discernidos. A análise integrada entre os litotipos, os lineamentos estruturais, a rede de drenagem e os padrões de formas de relevo discerniu os seguintes compartimentos morfoestruturais: Patamares de Cimeira da Mantiqueira (desmembrados em sete subcompartimentos, Patamares Escalonados da Mantiqueira (dois subcompartimentos, Cristas Quartzíticas Festonadas e Rebordos Erosivos Dissecados.

  18. Mixed-flow vertical tubular hydraulic turbine. Determination of proper design duty point

    Energy Technology Data Exchange (ETDEWEB)

    Sirok, B. [Ljubljana Univ. (Slovenia). Faculty of Mechanical Engineering; Bergant, A. [Litostroj Power, d.o.o., Ljubljana (Slovenia); Hoefler, E.

    2011-12-15

    A new vertical single-regulated mixed-flow turbine with conical guide apparatus and without spiral casing is presented in this paper. Runner blades are fixed to the hub and runner band and resemble to the Francis type runner of extremely high specific speed. Due to lack of information and guidelines for the design of a new turbine, a theoretical model was developed in order to determinate the design duty point, i.e. to determine the optimum narrow operation range of the turbine. It is not necessary to know the kinematic conditions at the runner inlet, but only general information on the geometry of turbine flow-passage, meridional contour of the runner and blading, the number of blades and the turbine speed of rotation. The model is based on the integral tangential lift coefficient, which is the average value over the entire runner blading. The results are calculated for the lift coefficient 0.5 and 0.6, for the flow coefficient range from 0.2 to 0.36, for the number of the blades between 5 and 13, and are finally presented in the Cordier diagram (specific speed vs. specific diameter). Calculated results of the turbine optimum operation in Cordier diagram correspond very well to the adequate area of Kaplan turbines with medium and low specific speed and extends into the area of Francis turbines with high specific speed. Presented model clearly highlights the parameters that affect specific load of the runner blade row and therefore the optimum turbine operation (discharge - turbine head). The presented method is not limited to a specific reaction type of the hydraulic turbine. The method can therefore be applied to a wide range from mixed-flow (radial-axial) turbines to the axial turbines. Applicability of the method may be considered as a tool in the first stage of the turbine design i.e. when designing the meridional geometry and selecting the number of blades according to calculated operating point. Geometric and energy parameters are generally defined to an

  19. SECTORAL RISK AND RETURN FOR COMPANIES IN ROMANIA

    Directory of Open Access Journals (Sweden)

    Anis Cecilia

    2012-12-01

    Full Text Available probability that cash flows or return will vary from expectations. Standard corporate finance theory supposes that a company chooses a capital structure that maximizes company value. A fundamental idea in finance is the relationship between risk and return. The greater the amount of risk that an investor is willing to take on, the greater the potential return. The reason for this is that investors need to be compensated for taking on additional risk. Why put capital at significant risk for a return that is no higher than the return on government bonds? Or expect higher than averages returns from low-risk activities? It is impossible to separate measuring the performance of a company from the risks that the management takes to achieve it.In most aspects of company operations, risk assessment plays a different but equally important, role. It is an integral part of informed decision taking in achieving performance. Risk assessment is involved from the highest level in strategic choices about what activities to undertake, what assets to buy or what markets to serve all the way to detailed operational decisions about whether to accept payment in foreign currencies and the adequacy of safety measures in the workplace. It plays a part whether or not an organization is aware of managing risk and many managers feel that their instinct and judgment are enough – a behavior risk. The danger is that this leaves company risk unplanned and unmanaged. This paper proposes a framework where we realized a study cases: we test if return on assets and return on equity has influence on the risk, both on long and short term. For this purposes, we conduct an empirical research that covers 59 selected companies traded at the Bucharest Stock Exchange within the time period 1999-2010. For this study our results reveal that dynamic global risk can be associated to a low intensity with total assets performance of the company’s. Investments efficiency and the

  20. Steam exit flow design for aft cavities of an airfoil

    Science.gov (United States)

    Storey, James Michael; Tesh, Stephen William

    2002-01-01

    Turbine stator vane segments have inner and outer walls with vanes extending therebetween. The inner and outer walls have impingement plates. Steam flowing into the outer wall passes through the impingement plate for impingement cooling of the outer wall surface. The spent impingement steam flows into cavities of the vane having inserts for impingement cooling the walls of the vane. The steam passes into the inner wall and through the impingement plate for impingement cooling of the inner wall surface and for return through return cavities having inserts for impingement cooling of the vane surfaces. A skirt or flange structure is provided for shielding the steam cooling impingement holes adjacent the inner wall aerofoil fillet region of the nozzle from the steam flow exiting the aft nozzle cavities. Moreover, the gap between the flash rib boss and the cavity insert is controlled to minimize the flow of post impingement cooling media therebetween. This substantially confines outflow to that exiting via the return channels, thus furthermore minimizing flow in the vicinity of the aerofoil fillet region that may adversely affect impingement cooling thereof.

  1. Climate and vegetation changes around the Atlantic Ocean resulting from changes in the meridional overturning circulation during deglaciation

    OpenAIRE

    D. Handiani; A. Paul; L. Dupont

    2012-01-01

    The Bølling-Allerød (BA, starting ~ 14.5 ka BP) is one of the most pronounced abrupt warming periods recorded in ice and pollen proxies. The leading explanation of the cause of this warming is a sudden increase in the rate of deepwater formation in the North Atlantic Ocean and the resulting effect on the heat transport by the Atlantic Meridional Overturning Circulation (AMOC). In this study, we used the University of Victoria (UVic) Earth System-Climate Mod...

  2. De Indios “Bárbaros” a Vasallos en la Frontera Meridional Chilena Durante el Reformismo Borbónico.

    OpenAIRE

    Chauca García, Jorge

    2017-01-01

    Con la presente Tesis Doctoral abordamos críticamente la visión ilustrada del indígena de la frontera meridional chilena como marco geográfico y la centuria de la Ilustración como coordenada temporal, especialmente su segunda mitad. Un análisis de sus tres familias básicas que no contempla por razones cronológicas a los picunches o gentes del norte, pero sí a los mapuches –gente de la tierra–, huilliches –gente...

  3. Mechanisms of meridional transport processes in the tropical Atlantic; Mechanismen meridionaler Transportprozesse im tropischen Atlantik

    Energy Technology Data Exchange (ETDEWEB)

    Kroeger, J.

    2001-07-01

    Meridional transport processes of water masses and tracers in the subtropical and tropical Atlantic are investigated using a regional eddy resolving model of the wind driven and thermohaline circulation. Analytical emphasis is on float simulations in the model which, complementary to Eulerian means, represent the Lagrangian view and give further insight into the spreading and pathways of characteristic water masses in this area. In the tropics and subtropics shallow 3-dimensional circulation cells are superimposed on the northward warm water transfer within the deep reaching thermohaline overturning cell (MOC) as part of the global ''Conveyor Belt''. Under present-day climate conditions the model shows that the equatorial thermocline is exclusively ventilated by subsurface flow within the tropical-subtropical cell (STC) of the South Atlantic. Only with a prescribed ''Conveyor-off''-Mode the STC of the North Atlantic contributes to this ventilation process with equal amounts. Throughout the year the interhemispheric transport of surface and central water masses of South Atlantic origin into the Caribbean Sea is dominated by zonal detours to the east as a consequence of the interplay of several retroflection events occuring in the North Atlantic. The eulerian mean flow field in the deep layer postulates the interhemispheric mass transport into the South Atlantic to be confined entirely to the western boundary, whereas Lagrangian means indicate intermittent eastward excursions along the equator, related to seasonally alternating zonal currents due to long Rossby waves. It was suggested that the observed characteristic eastward maximum of tracer concentrations along the equator is a consequence of rectifying effects of single or interacting equatorial waves. The model does not validate this hypothesis. The response to transport anomalies of subpolar origin and long periodicity is subject to different time-scales in both

  4. 26 CFR 301.6103(h)(2)-1 - Disclosure of returns and return information (including taxpayer return information) to and by...

    Science.gov (United States)

    2010-04-01

    ... administration. 301.6103(h)(2)-1 Section 301.6103(h)(2)-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT... Returns Returns and Records § 301.6103(h)(2)-1 Disclosure of returns and return information (including..., shall, to the extent provided by section 6103(h)(2) (A), (B), and (C) and subject to the requirements of...

  5. On the rate of return and risk factors to international oil companies in Iran's buy-back service contracts

    International Nuclear Information System (INIS)

    Ghandi, Abbas; Lin Lawell, C.-Y. Cynthia

    2017-01-01

    We analyze the rate of return (ROR) and risk factors faced by Shell Exploration, an international oil company (IOC), in its Soroosh and Nowrooz buy-back service contract in Iran. In particular, based on our models of cash flow, we analyze the buy-back contract specific risk factors that can contribute to a reduction in the rate of return for the international oil company. Our cash flow models resemble the cash flow of buy-back service contracts before the Iranian government changed the way it determined the capital cost ceiling and pre-defined the oil price in these contracts in 2008–2009. Our actual and contractual cash flow models reveal that Shell Exploration's actual ROR was much lower than the contractual level. Furthermore, we find that among the risk factors that we considered, a capital cost overrun has the greatest negative effect on the IOC's ROR. Moreover, we show that there is a potential for modifying the contracts in order for the IOC to face an actual ROR closer to the contractual ROR even if the contract faces cost overrun or delay, without exceeding the maximum contractual ROR that the National Iranian Oil Company is willing to give. - Highlights: • Buy-back contract specific risk factors can reduce the rate of return. • Shell Exploration's actual ROR was much lower than the contractual level. • A capital cost overrun has the greatest negative effect on the rate of return. • Contracts can be modified to better share the risk.

  6. Inter-comparison of stratospheric mean-meridional circulation and eddy mixing among six reanalysis data sets

    Directory of Open Access Journals (Sweden)

    K. Miyazaki

    2016-05-01

    Full Text Available The stratospheric mean-meridional circulation (MMC and eddy mixing are compared among six meteorological reanalysis data sets: NCEP-NCAR, NCEP-CFSR, ERA-40, ERA-Interim, JRA-25, and JRA-55 for the period 1979–2012. The reanalysis data sets produced using advanced systems (i.e., NCEP-CFSR, ERA-Interim, and JRA-55 generally reveal a weaker MMC in the Northern Hemisphere (NH compared with those produced using older systems (i.e., NCEP/NCAR, ERA-40, and JRA-25. The mean mixing strength differs largely among the data products. In the NH lower stratosphere, the contribution of planetary-scale mixing is larger in the new data sets than in the old data sets, whereas that of small-scale mixing is weaker in the new data sets. Conventional data assimilation techniques introduce analysis increments without maintaining physical balance, which may have caused an overly strong MMC and spurious small-scale eddies in the old data sets. At the NH mid-latitudes, only ERA-Interim reveals a weakening MMC trend in the deep branch of the Brewer–Dobson circulation (BDC. The relative importance of the eddy mixing compared with the mean-meridional transport in the subtropical lower stratosphere shows increasing trends in ERA-Interim and JRA-55; this together with the weakened MMC in the deep branch may imply an increasing age-of-air (AoA in the NH middle stratosphere in ERA-Interim. Overall, discrepancies between the different variables and trends therein as derived from the different reanalyses are still relatively large, suggesting that more investments in these products are needed in order to obtain a consolidated picture of observed changes in the BDC and the mechanisms that drive them.

  7. How to organise return handling; an exploratory study with nine retailer warehouses

    NARCIS (Netherlands)

    M.B.M. de Koster (René); M.P. de Brito (Marisa); M.A. van de Vendel (Masja)

    2002-01-01

    textabstractAlready for a long time retailers take back products. In this paper we explore the factors contributing to the decision of combining vs. separating inbound and outbound flows during the return handling process. We do so through a comparative analysis of the operations in nine

  8. Meridional circulation in rotating stars. VII. The effects of chemical inhomogeneities

    International Nuclear Information System (INIS)

    Tassoul, M.; Tassoul, J.

    1984-01-01

    In this paper we discuss the effects of a gradient of mean molecular weight μ on the rotationally driven currents that pervade the radiative zone of a single, nonmagnetic, main-sequence star. Detailed numerical calculations are made for the hydrogen-burning core of a solar-type star, assuming that departures from spherical symmetry are not too large. It is found that meridional streaming virtually dies out from the center outward as the μ-gradient grows in a leisurely fashion. This prevents a substantial mixing of matter between the inner (inhomogeneous) and outer (homogeneous) regions in the radiative zone, although the inner region may be penetrated to some degree. To first order in the ratio of the centrifugal force to gravity at the equator, this pattern of circulation is independent of the mean angular velocity. To this order, then, there is no critical rotation rate above which unimpeded mixing may take place. These quantitative results are compared with diverse statements that can be found in the phenomenological literature on rotational mixing

  9. The return to work discussion: a qualitative study of the line manager conversation about return to work and the development of an educational programme.

    Science.gov (United States)

    Cohen, Debbie; Allen, Joanna; Rhydderch, Melody; Aylward, Mansel

    2012-07-01

    To investigate the conversation between line manager and employee about return to work to inform the development of an online interactive educational programme for line managers to improve the effectiveness of their discussions. An inductive qualitative approach, using the principles of action research and motivational interviewing were adopted. The results informed the development of the educational programme for line managers. Middle grade line managers in a large public services employer in the UK. Four discussion groups were conducted over a period of 8 months. Line managers explored the challenges of the return to work interview, analysed their interactions with employees and constructed the content of an educational programme. Multiple methods were used to build engagement with participants, including video and role-play. Nine line managers were recruited across 3 business areas. Managers recognised that their conversations focused on the organisations' policies and procedures and the outcome, rather than the interaction. They recognised the strength of shifting style to shared decision-making and guidance rather than process and instruction. These communication strategies were depicted in the educational programme. The content and flow of the return to work discussion is of high importance and influences employee behaviour and return to work outcomes.

  10. Predictable return distributions

    DEFF Research Database (Denmark)

    Pedersen, Thomas Quistgaard

    trace out the entire distribution. A univariate quantile regression model is used to examine stock and bond return distributions individually, while a multivariate model is used to capture their joint distribution. An empirical analysis on US data shows that certain parts of the return distributions......-of-sample analyses show that the relative accuracy of the state variables in predicting future returns varies across the distribution. A portfolio study shows that an investor with power utility can obtain economic gains by applying the empirical return distribution in portfolio decisions instead of imposing...

  11. Linear and nonlinear stability of a thermally stratified magnetically driven rotating flow in a cylinder.

    Science.gov (United States)

    Grants, Ilmars; Gerbeth, Gunter

    2010-07-01

    The stability of a thermally stratified liquid metal flow is considered numerically. The flow is driven by a rotating magnetic field in a cylinder heated from above and cooled from below. The stable thermal stratification turns out to destabilize the flow. This is explained by the fact that a stable stratification suppresses the secondary meridional flow, thus indirectly enhancing the primary rotation. The instability in the form of Taylor-Görtler rolls is consequently promoted. These rolls can only be excited by finite disturbances in the isothermal flow. A sufficiently strong thermal stratification transforms this nonlinear bypass instability into a linear one reducing, thus, the critical value of the magnetic driving force. A weaker temperature gradient delays the linear instability but makes the bypass transition more likely. We quantify the non-normal and nonlinear components of this transition by direct numerical simulation of the flow response to noise. It is observed that the flow sensitivity to finite disturbances increases considerably under the action of a stable thermal stratification. The capabilities of the random forcing approach to identify disconnected coherent states in a general case are discussed.

  12. Return-to-Work Program for Injured Workers: Factors of Successful Return to Employment.

    Science.gov (United States)

    Awang, Halimah; Shahabudin, Sharifah Muhairah; Mansor, Norma

    2016-11-01

    This study examined the factors of successful return to employment among participants in the return to work program (RTW) following work-related injury. Data were obtained from the Social Security Organization database containing 9850 injured workers who underwent RTW in 2010 to 2013. About 65% had successfully returned to employment. Significant factors of successful return include gender, employer interest, motivation, age, intervention duration, and type of injury. Male and motivated employees were more likely to return to employment compared with female and unmotivated employees, respectively. Participants from interested employers were 23.22 times more likely to return to work than those from uninterested employers, whereas participants whose intervention period exceeded 5 months were 41% less likely to return to work compared with those whose intervention period was within 3 months. Appropriate strategy and enhanced collaboration between the stakeholders would improve the proportion of successful return to employment. © 2016 APJPH.

  13. Frequency Dependence of Helioseismic Measurements of the Center-to-Limb Effect and Flow-induced Travel-time Shifts

    Science.gov (United States)

    Chen, Ruizhu; Zhao, Junwei

    2018-02-01

    Time–distance helioseismology measures acoustic travel times to infer the structure and flow field of the solar interior; however, both the mean travel times and the travel-time shifts suffer systematic center-to-limb variations, which complicate the interpretation and inversions of the time–distance measurements. In particular, the center-to-limb variation in travel-time shifts (CtoL effect) has a significant impact on the inference of the Sun’s meridional circulation, and needs to be removed from the helioseismic measurements, although the observational properties and the physical cause of the CtoL effect have yet to be investigated. In this study, we measure the CtoL effect in the frequency domain using Doppler-velocity data from the Solar Dynamics Observatory/Helioseismic and Magnetic Imager, and study its properties as a function of disk-centric distance, travel distance, and frequency of acoustic waves. It is found that the CtoL effect has a significant frequency dependence—it reverses sign at a frequency around 5.4 mHz and reaches maximum at around 4.0 mHz before the sign reversal. The tendency of frequency dependence varies with disk-centric distance in a way that both the sign-reversal frequency and the maximum-value frequency decrease closer to the limb. The variation tendency does not change with travel distance, but the variation magnitude is approximately proportional to travel distance. For comparison, the flow-induced travel-time shifts show little frequency dependence. These observational properties provide more clues on the nature of the CtoL effect, and also possibly lead to new ways of effect-removal for a more robust determination of the deep meridional flow.

  14. A study on relationship between earnings before tax, interest and operational cash flows with stockholders’ equity

    Directory of Open Access Journals (Sweden)

    Mohammad Reza karimi Torghabeh

    2014-08-01

    Full Text Available One of the primary economic issues is associated with optimum resource allocation in profitable investments with reasonable risk. For this purpose, performance measurement’s criteria are needed some of which emphasize cash flow variables and some others focus on information content of accounting profit. On this basis, this study examines the relationship between earnings before tax and interest and operational cash flows with stockholders’ return in Tehran Stock Exchange (TSE. In this regard, information asymmetry was also examined. To test hypotheses, multivariable regression and combined data method were used. The results showed that based on the information of 102 companies in stock market from 2004 to 2009, there was a positive and significant correlation between earnings before interest and tax and stock return in the companies. While, operational cash flow has no significant impact on stock return. Increasing information asymmetry, earnings before interest and tax has a positive and significant correlation with stockholders ’return; but operational cash flow has no significant effect on stockholders’ return. In other words, earnings before interest and tax have higher information content than operational cash flow.

  15. High performance hydraulic design techniques of mixed-flow pump impeller and diffuser

    International Nuclear Information System (INIS)

    Kim, Sung; Lee, Kyoung Yong; Kim, Joon Hyung; Kim, Jin Hyuk; Jung, Uk Hee; Choi, Young Seok

    2015-01-01

    In this paper, we describe a numerical study about the performance improvement of a mixed-flow pump by optimizing the design of the impeller and diffuser using a commercial computational fluid dynamics (CFD) code and design-of-experiments (DOE). The design variables of impeller and diffuser in the vane plane development were defined with a fixed meridional plane. The design variables were defined by the vane plane development, which indicates the blade-angle distributions and length of the impeller and diffuser. The vane plane development was controlled using the blade-angle in a fixed meridional plane. The blade shape of the impeller and diffuser were designed using a traditional method in which the inlet and exit angles are connected smoothly. First, the impeller optimum design was performed with impeller design variables. The diffuser optimum design was performed with diffuser design variables while the optimally designed impeller shape was fixed. The importance of the impeller and diffuser design variables was analyzed using 2 k factorial designs, and the design optimization of the impeller and diffuser design variables was determined using the response surface method (RSM). The objective functions were defined as the total head (Ht) and the total efficiency (ηt) at the design flow rate. The optimally designed model was verified using numerical analysis, and the numerical analysis results for both the optimum model and the reference model were compared to determine the reasons for the improved pump performance. A pump performance test was carried out for the optimum model, and its reliability was proved by a comparative analysis of the results of the numerical analysis and an experiment using the optimum model.

  16. A Conceptual Model for Calculating the Return of Costs Invested in the Creation of an Economic Security Service, During a Short-Term Period

    Directory of Open Access Journals (Sweden)

    Melikhova Tetiana O.

    2018-02-01

    Full Text Available The article is aimed at suggesting methods for calculating the short-term period of return of costs invested in creation of an economic security service. The article considers approaches to calculation of the period of return of costs, advanced at the level of enterprise, which build the methodical basis for definition of such period. At the level of structural subdivisions of enterprise, which do not produce products, it is suggested to use conditional money flow as a source of financing advanced costs. The calculation of the short-term return on investment at the enterprise level provides for: allocation of expenses for the permanent and the replacement parts during the year; determination of the production of money flow and the money flow accumulated during the year. Annual depreciation payments are the basis of fixed costs. Methods of determination of the gross, net, valid, and specified periods of return of costs, advanced during the year for introduction of an economic security service at enterprise, have been suggested.

  17. Estado actual de las investigaciones tafonómicas naturalistas en Punta Entrada y Monte León (patagonia meridional)

    OpenAIRE

    Muñoz, Sebastián Ramón; Cruz, Isabel

    2017-01-01

    Se presentan los resultados de las investigaciones tafonómicas naturalistas realizadas desde 2005 en la desembocadura del río Santa Cruz y el parque Nacional Monte león (Patagonia Meridional) dirigidas a conocer los modos en que tiene lugar el reciclado de restos de vertebrados en un mismo contexto ambiental, la estepa costera patagónica. Se resume el conocimiento generado sobre: el tiempo involucrado en la desarticulación de carcasas de vertebrados; los procesos y actores intervinientes y ...

  18. 26 CFR 1.6013-2 - Joint return after filing separate return.

    Science.gov (United States)

    2010-04-01

    ... the case of a joint return made under section 6013(b), the period of limitations provided in sections... (c)(1) of this section, relating to the application of sections 6501 and 6651 with respect to a joint... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Joint return after filing separate return. 1...

  19. The Risk Return Relationship: Evidence from Index Return and Realised Variance Series

    OpenAIRE

    Minxian Yang

    2014-01-01

    The risk return relationship is analysed in bivariate models for return and realised variance(RV) series. Based on daily time series from 21 international market indices for more than 13 years (January 2000 to February 2013), the empirical findings support the arguments of risk return tradeoff, volatility feedback and statistical balance. It is reasoned that the empirical risk return relationship is primarily shaped by two important data features: the negative contemporaneous correlation betw...

  20. Effect of wheat-maize straw return on the fate of nitrate in groundwater in the Huaihe River Basin, China.

    Science.gov (United States)

    Li, Rongfu; Ruan, Xiaohong; Bai, Ying; Ma, Tianhai; Liu, Congqiang

    2017-08-15

    Straw return is becoming a routine practice in disposing of crop residues worldwide. However, the potential effect of such operation on the chemistry of local groundwater is not well documented. Here, shallow groundwater in an area where wheat-maize straw return is practiced was analyzed, and the seasonal changes in the nitrate concentration and the isotope compositions of NO 3 - and H 2 O were determined along two flow paths. Measured δD and δ 18 O in waters indicated that the groundwater was mainly recharged by atmospheric precipitation, while measured δ 15 N and δ 18 O in nitrate suggested that the sources for groundwater NO 3 - included urea fertilizer, soil nitrogen, and sewage/manure. Reduced NO 3 - concentrations coincided with an enrichment of organic matter in the groundwater of the straw return area, revealing an environmental condition that facilitates nitrate reduction, whereas increased δ 15 N-NO 3 - and δ 18 O-NO 3 - along the flow path suggested the occurrence of denitrification. Further analyses showed that, compared to the cases in the absence of straw return, as much as 80% and 90% of groundwater nitrate was removed in low and high water seasons in the straw return area, pointing to a potential positive effect of straw return to groundwater quality. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. PRODUCT RETURNS MANAGEMENT IN THE CLOTHING INDUSTRY IN POLAND

    Directory of Open Access Journals (Sweden)

    Anna Maria Jeszka

    2014-12-01

    Full Text Available Background: The aim of this study is to identify and define on the basis of the literature the principal external and organizational factors and check to what extent they affect the efficiency of returns management as well as any resultant savings. The author proposes a conceptual model which correlates the results of returns management as well as savings with the main determinants identified on the basis of the literature. Then, in the operationalisation phase of the model, the dependent and independent variables were defined in the form of constructs. In accordance with the adopted model, individual constructs were measured based on standardised interviews. Materials and methods:  The results of returns management and any savings generated by this process are affected by certain determinants which are described in the literature. The adopted model included external factors, such as the cooperation of retailers with logistics operators and suppliers, the exchange of information in the supply chain, and organizational behaviour (experience of employees; as well as organizational factors related to the flow of information and IT systems. Due to financial and organisational restrictions, the originally planned representative sample of retail chains was limited to the regions of Wielkopolska and Lubuskie. In the end, 105 interviews were analysed. Results:  The results obtained in the research sample confirm assumptions about the possible potential savings that can be achieved as a result of appropriately conducted corporate policies in the area of reverse logistics. A correlation was also revealed between the experience and competencies of staff and the efficiency of returns management. Conclusions: Research into the factors affecting the efficiency of returns management and any savings resulting from returns management policies have not been conducted in Poland to date. The present study contributes to the growing trend of research into the

  2. Upgrading the Arecibo Potassium Lidar Receiver for Meridional Wind Measurements

    Science.gov (United States)

    Piccone, A. N.; Lautenbach, J.

    2017-12-01

    Lidar can be used to measure a plethora of variables: temperature, density of metals, and wind. This REU project is focused on the set up of a semi steerable telescope that will allow the measurement of meridional wind in the mesosphere (80-105 km) with Arecibo Observatory's potassium resonance lidar. This includes the basic design concept of a steering system that is able to turn the telescope to a maximum of 40°, alignment of the mirror with the telescope frame to find the correct focusing, and the triggering and programming of a CCD camera. The CCD camera's purpose is twofold: looking though the telescope and matching the stars in the field of view with a star map to accurately calibrate the steering system and determining the laser beam properties and position. Using LabVIEW, the frames from the CCD camera can be analyzed to identify the most intense pixel in the image (and therefore the brightest point in the laser beam or stars) by plotting average pixel values per row and column and locating the peaks of these plots. The location of this pixel can then be plotted, determining the jitter in the laser and position within the field of view of the telescope.

  3. An investigation on how to estimate future cash flows: Evidence from Tehran Stock Exchange

    Directory of Open Access Journals (Sweden)

    Roghayeh Ahmdi Panah Banad Koki

    2014-03-01

    Full Text Available This paper presents an empirical investigation to predict future cash flows using present cash flow and accruals using the information of 96 selected firms listed on Tehran Stock Exchange over the period 2007-2011. The proposed study uses linear regression techniques to forecast future cash flow and the results indicate that cash flow and accruals together could provide more power to forecast cash flow. In addition, accrual provides future cash flow better than cash flow. The survey also performs an investigation on discretionary accrual and finds that the firms with higher accruals maintain lower return compared with firms with lower return. This means there is a clear evidence of discretionary accruals on Tehran Stock Exchange.

  4. «Theater of Sorrows»: Rhetoric and Space in Francisco Romero's «Llanto Sagrado de la América Meridional»

    Directory of Open Access Journals (Sweden)

    Jorge Martín García

    2016-11-01

    Full Text Available This article aims to analyze the text entitled Llanto sagrado de la América Meridional written by the Augustinian friar Francisco Romero. The work presents a kind of spiritual mapping of american land. Therefore, the text divides the territory of the continent according to their proximity or remoteness from the true faith. Our main objective will be to examine the rhetorical mechanisms that lie behind this description of the Indian space.

  5. Can tree-ring isotopes (δ18O and δ13C) improve our understanding of hydroclimate variability in the Columbia River Basin?

    Science.gov (United States)

    Csank, A. Z.; Wise, E.; McAfee, S. A.

    2015-12-01

    The trajectory of incoming storms from the Pacific Ocean has a strong impact on hydroclimate in the Pacific Northwest. Shifts between zonal and meridional flow are a key influence on drought and pluvial regimes in both the PNW and the western United States as a whole. Circulation-dependent variability in the isotopic composition of precipitation can be recorded and potentially reconstructed using δ18O records derived from tree-rings. Here we present isotopic records of δ18O and δ13C from ponderosa pine (Pinus ponderosa) for the period 1950-2013 from six sites located in the lee of the Cascades in eastern Washington. Because of the orientation of the Cascades, zonal flow will result in an intensified rain shadow whereas meridional flow allows moisture to penetrate at a lower elevation leading to a lower rainout effect. This means zonal flow results in drier conditions in eastern Washington and the converse for meridional flow. We hypothesized that more depleted precipitation δ18O values will occur with periods of more zonal flow across the PNW and will be recorded by trees at our sites. Results show a strong relationship between our δ18O chronologies and winter precipitation (R = -0.50; p<0.001). δ13C chronologies from the same trees showed a relationship to prior fall/winter (pOct-pDec) precipitation (R = -0.46; p<0.005) suggesting a possible link to antecedent moisture conditions. With a focus on years with clear zonal and meridional flow regimes, we regressed the tree-ring δ18O anomaly against the instrumental record of total precipitation and compared the residual series to records of storm track for the period 1978-2008, and we found a detectable signal where the most depleted δ18O was generally associated with zonal flow and the most enriched δ18O with meridional flow. However, there are still some years where the relationship is unclear. Further work is aimed at understanding these anomalous years and extending our record beyond the instrumental

  6. Migratory Patterns of Chinook Salmon Oncorhynchus tshawytscha Returning to a Large, Free-flowing River Basin

    Science.gov (United States)

    Eiler, John H.; Evans, Allison N.; Schreck, Carl B.

    2015-01-01

    Upriver movements were determined for Chinook salmon Oncorhynchus tshawytscha returning to the Yukon River, a large, virtually pristine river basin. These returns have declined dramatically since the late 1990s, and information is needed to better manage the run and facilitate conservation efforts. A total of 2,860 fish were radio tagged during 2002–2004. Most (97.5%) of the fish tracked upriver to spawning areas displayed continual upriver movements and strong fidelity to the terminal tributaries entered. Movement rates were substantially slower for fish spawning in lower river tributaries (28–40 km d-1) compared to upper basin stocks (52–62 km d-1). Three distinct migratory patterns were observed, including a gradual decline, pronounced decline, and substantial increase in movement rate as the fish moved upriver. Stocks destined for the same region exhibited similar migratory patterns. Individual fish within a stock showed substantial variation, but tended to reflect the regional pattern. Differences between consistently faster and slower fish explained 74% of the within-stock variation, whereas relative shifts in sequential movement rates between “hares” (faster fish becoming slower) and “tortoises” (slow but steady fish) explained 22% of the variation. Pulses of fish moving upriver were not cohesive. Fish tagged over a 4-day period took 16 days to pass a site 872 km upriver. Movement rates were substantially faster and the percentage of atypical movements considerably less than reported in more southerly drainages, but may reflect the pristine conditions within the Yukon River, wild origins of the fish, and discrete run timing of the returns. Movement data can provide numerous insights into the status and management of salmon returns, particularly in large river drainages with widely scattered fisheries where management actions in the lower river potentially impact harvests and escapement farther upstream. However, the substantial variation

  7. Preferencia de hábitat del murciélago hortelano meridional Eptesicus isabellinus (Temminck, 1840 en ambientes mediterráneos semiáridos

    Directory of Open Access Journals (Sweden)

    Lisón, F.

    2014-06-01

    Full Text Available Habitat preference of the meridional serotine bat Eptesicus isabellinus (Temminck, 1840 in semiarid Mediterranean landscapes Several molecular studies have recently reported the presence of a second species of the genus Eptesicus in the Iberian peninsula, the meridional serotine bat, E. isabellinus. This species is present in the south of Iberia and it seems to have an allopatric distribution with its twin species, E. serotinus. Ecological studies are now needed to understand the biology of E. isabellinus in southeast Spain. In this study, we used presence–only data for E. isabellinus to perform an ecological niche factor analysis (ENFA and to create a habitat suitability map (HSM. Our results show that the species has a low marginality index, suggesting it is well adapted to the semiarid conditions of the study area. The main habitats used by E. isabellinus are water courses, scrublands, and zones with high primary productivity. The species avoids non–irrigated cropland and shows no preference for human settlements or irrigated cropland. This study provides information about the ecology of E. isabellinus in southeast Spain and allows us to discuss relevant aspects for its conservation.

  8. Influence of the shaft rotation on the stability of magnetic fluid shaft seal characteristics

    Science.gov (United States)

    Krakov, M. S.; Nikiforov, I. V.

    2008-12-01

    Distribution of the magnetic particles concentration in a magnetic fluid shaft seal is studied numerically for a rotating shaft. It is revealed that the shaft rotation causes not only an azimuthal flow of the magnetic fluid, but a meridional flow as well. This meridional flow prevents the growth of magnetic particle concentration in the gap of the magnetic fluid shaft seal. As a result, the burst pressure of the magnetic fluid shaft seal for the rotating shaft is stable and does not change with time. Figs 6, Refs 7.

  9. [Ecological compensation standard in Dongting Lake region of returning cropland to lake based on emergy analysis].

    Science.gov (United States)

    Mao, De-Hua; Hu, Guang-Wei; Liu, Hui-Jie; Li, Zheng-Zui; Li, Zhi-Long; Tan, Zi-Fang

    2014-02-01

    The annual emergy and currency value of the main ecological service value of returning cropland to lake in Dongting Lake region from 1999 to 2010 was calculated based on emergy analysis. The calculation method of ecological compensation standard was established by calculating annual total emergy of ecological service function increment since the starting year of returning cropland to lake, and the annual ecological compensation standard and compensation area were analyzed from 1999 to 2010. The results indicated that ecological compensation standard from 1999 to 2010 was 40.31-86.48 yuan x m(-2) with the mean of 57.33 yuan x m(-2). The ecological compensation standard presented an increase trend year by year due to the effect of eco-recovery of returning cropland to lake. The ecological compensation standard in the research area presented a swift and steady growth trend after 2005 mainly due to the intensive economy development of Hunan Province, suggesting the value of natural ecological resources would increase along with the development of society and economy. Appling the emergy analysis to research the ecological compensation standard could reveal the dynamics of annual ecological compensation standard, solve the abutment problem of matter flow, energy flow and economic flow, and overcome the subjective and arbitrary of environment economic methods. The empirical research of ecological compensation standard in Dongting Lake region showed that the emergy analysis was feasible and advanced.

  10. Comparisons of LES and RANS Computations with PIV Experiments on a Cylindrical Cavity Flow

    Directory of Open Access Journals (Sweden)

    Wen-Tao Su

    2013-01-01

    Full Text Available A comparison study on the numerical computations by large eddy simulation (LES and Reynolds-averaged Navier-Stokes (RANS methods with experiment on a cylindrical cavity flow was conducted in this paper. Numerical simulations and particle image velocimetry (PIV measurement were performed for two Reynolds numbers of the flow at a constant aspect ratio of H/R = 2.4 (R is the radius of the cylindrical cavity, and H is liquid level. The three components of velocity were extracted from 100 sequential PIV measured velocity frames with averaging, in order to illustrate the axial jet flow evolution and circulation distribution in the radial direction. The results show that LES can reproduce well the fine structure inside the swirling motions in both the meridional and the horizontal planes, as well as the distributions of velocity components and the circulation, in good agreement with experimental results, while the RANS method only provided a rough trend of inside vortex structure. Based on the analysis of velocity profiles at various locations, it indicates that LES is more suitable for predicting the complex flow characteristics inside complicated three-dimensional geometries.

  11. Linking the South Atlantic Meridional Overturning Circulation and the Global Monsoons

    Science.gov (United States)

    Lopez, H.; Dong, S.; Goni, G. J.; Lee, S. K.

    2016-02-01

    This study tested the hypothesis whether low frequency decadal variability of the South Atlantic meridional heat transport (SAMHT) influences decadal variability of the global monsoons. A multi-century run from a state-of-the-art coupled general circulation model is used as basis for the analysis. Our findings indicate that multi-decadal variability of the South Atlantic Ocean plays a key role in modulating atmospheric circulation via interhemispheric changes in Atlantic Ocean heat content. Weaker SAMHT produces anomalous ocean heat divergence over the South Atlantic resulting in negative ocean heat content anomaly about 15 years later. This, in turn, forces a thermally direct anomalous interhemispheric Hadley circulation in the atmosphere, transporting heat from the northern hemisphere (NH) to the southern hemisphere (SH) and moisture from the SH to the NH, thereby intensify (weaken) summer (winter) monsoon in the NH and winter (summer) monsoon in the SH. Results also show that anomalous atmospheric eddies, both transient and stationary, transport heat northward in both hemispheres producing eddy heat flux convergence (divergence) in the NH (SH) around 15-30°, reinforcing the anomalous Hadley circulation. Overall, SAMHT decadal variability leads its atmospheric response by about 15 years, suggesting that the South Atlantic is a potential predictor of global climate variability.

  12. Células de Circulação Meridional Durante os Eventos Extremos de Gelo Marinho Antártico

    OpenAIRE

    Carpenedo, Camila Bertoletti; Ambrizzi, Tércio

    2016-01-01

    Resumo Como a borda do gelo marinho antártico está localizada em uma região muito sensível, sob a Frente Polar Antártica, existe um grande potencial da variabilidade do gelo marinho afetar a circulação atmosférica. Assim, o objetivo deste estudo foi investigar as possíveis relações entre os eventos extremos de gelo marinho antártico e as células de circulação meridional no Pacífico Sudeste, região onde há intensa variabilidade em várias escalas de tempo. Os resultados mostram que quando há ev...

  13. Predictability of Stock Returns

    Directory of Open Access Journals (Sweden)

    Ahmet Sekreter

    2017-06-01

    Full Text Available Predictability of stock returns has been shown by empirical studies over time. This article collects the most important theories on forecasting stock returns and investigates the factors that affecting behavior of the stocks’ prices and the market as a whole. Estimation of the factors and the way of estimation are the key issues of predictability of stock returns.

  14. Cross-Border Mergers and Acquisitions in China: A Test of the Free Cash Flow Hypothesis

    Directory of Open Access Journals (Sweden)

    Yane Chandera

    2014-08-01

    Full Text Available This research investigates whether Chinese cross-border investments have positive impact onshareholders wealth and whether the amount of bidders’ free cash flow influences the shareholderreturns resulted from the acquisitions. The sample is based on 77 top Chinese cross-border investmentsduring the years 2005-2009 with each deal value of minimum US$100 million. The assessmentsof acquisition abnormal returns are based on the event study methodology (Brown & Warner, 1985.Cross-sectional regression analysis is used to determine the bidding firms factors which significantlyaffect the returns. Factors are examined using OLS with White’s heteroscedasticity-corrected standarderrors, since the assumption of homoscedasticity is likely to be violated. The study proves Chinesecross- border acquisitions result in positive abnormal returns which is consistent with synergyhypothesis. The amount of bidders’ free cash flow is also found to be marginally but positively associatedwith shareholders return which is consistent with Myers and Majluf’s pecking order hypothesisbut unsupportive of Jensen’s free cash flow hypothesis.

  15. The role of boundary layer momentum advection in the mean location of the ITCZ

    Science.gov (United States)

    Dixit, Vishal; Srinivasan, J.

    2017-08-01

    The inter-tropical convergence zones (ITCZ) form closer to the equator during equinoxes while they form well away from the equator during the boreal summer. A simple three-way balance between the pressure gradients, Coriolis force and effective Rayleigh friction has been classically used to diagnose the location of maximum boundary layer convergence in the near equatorial ITCZ. If such a balance can capture the dynamics of off-equatorial convergence was not known. We used idealized aqua planet simulations with fixed, zonally symmetric sea surface temperature boundary conditions to simulate the near equatorial and off-equatorial ITCZ. As opposed to the convergence of inter-hemispheric flows in the near equatorial convergence, the off-equatorial convergence forms due to the deceleration of cross-equatorial meridional flow. The detailed momentum budget of the off-equatorial convergence zone reveals that the simple balance is not sufficient to capture the relevant dynamics. The deceleration of the meridional flow is strongly modulated by the inertial effects due to the meridional advection of zonal momentum in addition to the terms in the simple balance. The simple balance predicts a spurious near equatorial convergence and a consistent off-equatorial convergence of the meridional flow. The spurious convergence disappears when inertial effects are included in the balance. As cross equatorial meridional flow decelerates to form convergence, the inertial effects cancel the pressure gradient effects near the equator while they add away from the equator. The contribution to the off-equatorial convergence induced by the pressure gradients is significantly larger than the contribution due to the inertial effects and hence pressure gradients appear to be the primary factor in anchoring the strength and location of the off-equatorial convergence.

  16. An Efficient Return Algorithm For Non-Associated Plasticity With Linear Yield Criteria In Principal Stress Space

    DEFF Research Database (Denmark)

    Clausen, Johan Christian; Damkilde, Lars; Andersen, Lars

    2007-01-01

    . The stress return and the formation of the constitutive matrix is carried out in principal stress space. Here the manipulations simplify and rely on geometrical arguments. The singularities arising at the intersection of yield planes are dealt with in a straightforward way also based on geometrical......An efficient return algorithm for stress update in numerical plasticity computations is presented. The yield criterion must be linear in principal stress space and can be composed of any number of yield planes. Each of these yield planes may have an associated or non-associated flow rule...

  17. Migratory Patterns of Wild Chinook Salmon Oncorhynchus tshawytscha Returning to a Large, Free-Flowing River Basin.

    Directory of Open Access Journals (Sweden)

    John H Eiler

    Full Text Available Upriver movements were determined for Chinook salmon Oncorhynchus tshawytscha returning to the Yukon River, a large, virtually pristine river basin. These returns have declined dramatically since the late 1990s, and information is needed to better manage the run and facilitate conservation efforts. A total of 2,860 fish were radio tagged during 2002-2004. Most (97.5% of the fish tracked upriver to spawning areas displayed continual upriver movements and strong fidelity to the terminal tributaries entered. Movement rates were substantially slower for fish spawning in lower river tributaries (28-40 km d-1 compared to upper basin stocks (52-62 km d-1. Three distinct migratory patterns were observed, including a gradual decline, pronounced decline, and substantial increase in movement rate as the fish moved upriver. Stocks destined for the same region exhibited similar migratory patterns. Individual fish within a stock showed substantial variation, but tended to reflect the regional pattern. Differences between consistently faster and slower fish explained 74% of the within-stock variation, whereas relative shifts in sequential movement rates between "hares" (faster fish becoming slower and "tortoises" (slow but steady fish explained 22% of the variation. Pulses of fish moving upriver were not cohesive. Fish tagged over a 4-day period took 16 days to pass a site 872 km upriver. Movement rates were substantially faster and the percentage of atypical movements considerably less than reported in more southerly drainages, but may reflect the pristine conditions within the Yukon River, wild origins of the fish, and discrete run timing of the returns. Movement data can provide numerous insights into the status and management of salmon returns, particularly in large river drainages with widely scattered fisheries where management actions in the lower river potentially impact harvests and escapement farther upstream. However, the substantial variation

  18. The Return to Foreign Aid

    DEFF Research Database (Denmark)

    Dalgaard, Carl-Johan Lars; Hansen, Henrik

    2017-01-01

    We estimate the average rate of return on investments financed by aid and by domestic resource mobilisation, using aggregate data. Both returns are expected to vary across countries and time. Consequently we develop a correlated random coefficients model to estimate the average returns. Across...... different estimators and two different data sources for GDP and investment our findings are remarkably robust; the average gross return on ‘aid investments’ is about 20 per cent. This is in accord with micro estimates of the economic rate of return on aid projects and with aggregate estimates of the rate...

  19. Land-falling typhoons are controlled by the meridional oscillation of the Kuroshio Extension

    Science.gov (United States)

    Huang, Shihming; Oey, Lie-Yauw

    2018-06-01

    Low-frequency variations of typhoon paths are often attributed to changes in the North Pacific subtropical high and monsoon through influences on the steering wind. Evidence indicates however a strong imprint of the Kuroshio on the atmosphere. Here we show that the meridional oscillation of sea surface temperature (SST) front over the Kuroshio Extension east of Japan significantly correlates with the number of land-falling typhoons along East Asia from June to October, accounting for 70% of the low-frequency variance since 1980. We used observations and a simple model to show that when the SST front shifts poleward (equatorward), SST gradient south of the current and westerly tropospheric wind weaken (strengthen), steering more typhoons to veer toward (away from) the East Asian continent. Our analysis also indicates that long-term weakening of SST gradient and westerly wind appears to be concomitant with poleward shifting of the Kuroshio, attributed to global warming in some studies, and suggests the potential for more land-falling typhoons in East Asia in the coming decades.

  20. GIS-aided low flow mapping

    Science.gov (United States)

    Saghafian, B.; Mohammadi, A.

    2003-04-01

    Most studies involving water resources allocation, water quality, hydropower generation, and allowable water withdrawal and transfer require estimation of low flows. Normally, frequency analysis on at-station D-day low flow data is performed to derive various T-yr return period values. However, this analysis is restricted to the location of hydrometric stations where the flow discharge is measured. Regional analysis is therefore conducted to relate the at-station low flow quantiles to watershed characteristics. This enables the transposition of low flow quantiles to ungauged sites. Nevertheless, a procedure to map the regional regression relations for the entire stream network, within the bounds of the relations, is particularly helpful when one studies and weighs alternative sites for certain water resources project. In this study, we used a GIS-aided procedure for low flow mapping in Gilan province, part of northern region in Iran. Gilan enjoys a humid climate with an average of 1100 mm annual precipitation. Although rich in water resources, the highly populated area is quite dependent on minimum amount of water to sustain the vast rice farming and to maintain required flow discharge for quality purposes. To carry out the low flow analysis, a total of 36 hydrometric stations with sufficient and reliable discharge data were identified in the region. The average area of the watersheds was 250 sq. km. Log Pearson type 3 was found the best distribution for flow durations over 60 days, while log normal fitted well the shorter duration series. Low flows with return periods of 2, 5, 10, 25, 50, and 100 year were then computed. Cluster analysis identified two homogeneous areas. Although various watershed parameters were examined in factor analysis, the results showed watershed area, length of the main stream, and annual precipitation were the most effective low flow parameters. The regression equations were then mapped with the aid of GIS based on flow accumulation maps

  1. Mutual Fund Flows and Performance in Rational Markets

    OpenAIRE

    Jonathan B. Berk; Richard C. Green

    2004-01-01

    We develop a simple rational model of active portfolio management that provides a natural benchmark against which to evaluate observed relationship between returns and fund flows. Many effects widely regarded as anomalous are consistent with this simple explanation. In the model, investments with active managers do not outperform passive benchmarks because of the competitive market for capital provision, combined with decreasing returns to scale in active portfolio management. Consequently, p...

  2. Probability modeling of high flow extremes in Yingluoxia watershed, the upper reaches of Heihe River basin

    Science.gov (United States)

    Li, Zhanling; Li, Zhanjie; Li, Chengcheng

    2014-05-01

    Probability modeling of hydrological extremes is one of the major research areas in hydrological science. Most basins in humid and semi-humid south and east of China are concerned for probability modeling analysis of high flow extremes. While, for the inland river basin which occupies about 35% of the country area, there is a limited presence of such studies partly due to the limited data availability and a relatively low mean annual flow. The objective of this study is to carry out probability modeling of high flow extremes in the upper reach of Heihe River basin, the second largest inland river basin in China, by using the peak over threshold (POT) method and Generalized Pareto Distribution (GPD), in which the selection of threshold and inherent assumptions for POT series are elaborated in details. For comparison, other widely used probability distributions including generalized extreme value (GEV), Lognormal, Log-logistic and Gamma are employed as well. Maximum likelihood estimate is used for parameter estimations. Daily flow data at Yingluoxia station from 1978 to 2008 are used. Results show that, synthesizing the approaches of mean excess plot, stability features of model parameters, return level plot and the inherent independence assumption of POT series, an optimum threshold of 340m3/s is finally determined for high flow extremes in Yingluoxia watershed. The resulting POT series is proved to be stationary and independent based on Mann-Kendall test, Pettitt test and autocorrelation test. In terms of Kolmogorov-Smirnov test, Anderson-Darling test and several graphical diagnostics such as quantile and cumulative density function plots, GPD provides the best fit to high flow extremes in the study area. The estimated high flows for long return periods demonstrate that, as the return period increasing, the return level estimates are probably more uncertain. The frequency of high flow extremes exhibits a very slight but not significant decreasing trend from 1978 to

  3. Flow Energy Piezoelectric Bimorph Nozzle Harvester

    Science.gov (United States)

    Sherrit, Stewart (Inventor); Walkemeyer, Phillip E. (Inventor); Hall, Jeffrey L. (Inventor); Lee, Hyeong Jae (Inventor); Colonius, Tim (Inventor); Tosi, Phillipe (Inventor); Kim, Namhyo (Inventor); Sun, Kai (Inventor); Corbett, Thomas Gary (Inventor); Arrazola, Alvaro Jose (Inventor)

    2016-01-01

    A flow energy harvesting device having a harvester pipe includes a flow inlet that receives flow from a primary pipe, a flow outlet that returns the flow into the primary pipe, and a flow diverter within the harvester pipe having an inlet section coupled to the flow inlet, a flow constriction section coupled to the inlet section and positioned at a midpoint of the harvester pipe and having a spline shape with a substantially reduced flow opening size at a constriction point along the spline shape, and an outlet section coupled to the constriction section. The harvester pipe may further include a piezoelectric structure extending from the inlet section through the constriction section and point such that the fluid flow past the constriction point results in oscillatory pressure amplitude inducing vibrations in the piezoelectric structure sufficient to cause a direct piezoelectric effect and to generate electrical power for harvesting.

  4. The role of salinity in the decadal variability of the North Atlantic meridional overturning circulation

    Energy Technology Data Exchange (ETDEWEB)

    Frankignoul, Claude [Universite Pierre et Marie Curie, Paris 6, LOCEAN/IPSL, Paris Cedex 05 (France); Deshayes, Julie; Curry, Ruth [Woods Hole Oceanographic Institution, Woods Hole, MA (United States)

    2009-11-15

    An OGCM hindcast is used to investigate the linkages between North Atlantic Ocean salinity and circulation changes during 1963-2003. The focus is on the eastern subpolar region consisting of the Irminger Sea and the eastern North Atlantic where a careful assessment shows that the simulated interannual to decadal salinity changes in the upper 1,500 m reproduce well those derived from the available record of hydrographic measurements. In the model, the variability of the Atlantic meridional overturning circulation (MOC) is primarily driven by changes in deep water formation taking place in the Irminger Sea and, to a lesser extent, the Labrador Sea. Both are strongly influenced by the North Atlantic Oscillation (NAO). The modeled interannual to decadal salinity changes in the subpolar basins are mostly controlled by circulation-driven anomalies of freshwater flux convergence, although surface salinity restoring to climatology and other boundary fluxes each account for approximately 25% of the variance. The NAO plays an important role: a positive NAO phase is associated with increased precipitation, reduced northward salt transport by the wind-driven intergyre gyre, and increased southward flows of freshwater across the Greenland-Scotland ridge. Since the NAO largely controlled deep convection in the subpolar gyre, fresher waters are found near the sinking region during convective events. This markedly differs from the active influence on the MOC that salinity exerts at decadal and longer timescales in most coupled models. The intensification of the MOC that follows a positive NAO phase by about 2 years does not lead to an increase in the northward salt transport into the subpolar domain at low frequencies because it is cancelled by the concomitant intensification of the subpolar gyre which shifts the subpolar front eastward and reduces the northward salt transport by the North Atlantic Current waters. This differs again from most coupled models, where the gyre

  5. 76 FR 22611 - Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic...

    Science.gov (United States)

    2011-04-22

    ... Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic Media... Register on Wednesday, March 30, 2011 (76 FR 17521) providing guidance to specified tax return preparers who prepare and file individual income tax returns using magnetic media pursuant to section 6011(e)(3...

  6. Interdecadal North-Atlantic meridional overturning circulation variability in EC-EARTH

    Energy Technology Data Exchange (ETDEWEB)

    Wouters, Bert; Drijfhout, Sybren; Hazeleger, Wilco

    2012-12-15

    The Atlantic meridional overturning circulation (AMOC) in a 600 years pre-industrial run of the newly developed EC-EARTH model features marked interdecadal variability with a dominant time-scale of 50-60 years. An oscillation of approximately 2 Sverdrup (1 Sv = 10{sup 6} m{sup 3} s{sup -1}) is identified, which manifests itself as a monopole causing the overturning to simultaneously strengthen (/weaken) and deepen (/shallow) as a whole. Eight years before the AMOC peaks, density in the Labrador-Irminger Sea region reaches a maximum, triggering deep water formation. This density change is caused by a counterclockwise advection of temperature and salinity anomalies at lower latitudes, which we relate to the north-south excursions of the subpolar-subtropical gyre boundary and variations in strength and position of the subpolar gyre and the North Atlantic Current. The AMOC fluctuations are not directly forced by the atmosphere, but occur in a delayed response of the ocean to forcing by the North Atlantic Oscillation, which initiates ''intergyre''-gyre fluctuations. Associated with the AMOC is a 60-year sea surface temperature variability in the Atlantic, with a pattern and timescale showing similarities with the real-world Atlantic Multidecadal Variability. This good agreement with observations lends a certain degree of credibility that the mechanism that is described in this article could be seen as representative of the real climate system. (orig.)

  7. Dynamics of the low latitude thermosphere and ionosphere

    International Nuclear Information System (INIS)

    Burnside, R.G.

    1984-01-01

    Nighttime thermospheric neutral wind velocities were determined at Arecibo, Puerto Rico, by using a Fabry-Perot interferometer, which measures the Doppler shift of the O( 1 D) airglow emission. In summer, the winds are observed to flow toward the southeast between sunset and midnight. After midnight in summer, the meridional component of the wind usually slackens, while the zonal component may reverse. By contrast, in winter, the meridional wind is often small, and the predominant flow is eastward throughout the night. Vertical winds are inferred from the divergence of the horizontal flow. A maximum downward flow of about 5 m sπ 1 is observed near midnight in summer. Incoherent scatter radar measurements were used to calculate the O + diffusion velocity and infer the vertical profile of the meridional wind. Horizontal temperature gradients and ion-drag forces were evaluated from radar measurements. It is concluded that it may sometimes be necesary to include viscous forces to balance the meridional equation of motion for the neutral gas. Electrical conductivities of the E and F layers of the nighttime ionosphere were determined. The F layer Pedersen conductivity at the magnetically conjugate point was evaluated using ionosonde data. The F layer dynamo mechanism was found to be the source of most of the nighttime electric fields observed at Arecibo

  8. Assessment of hand blood flow: a modified technique

    International Nuclear Information System (INIS)

    Kirsh, J.C.; Tepperman, P.S.

    1985-01-01

    A blood flow artifact has been identified with the conventional bolus-injection technique in radionuclide studies of hand disorders. The artifact, consisting of increased blood flow on the injected side, was demonstrated in 22 of 25 subjects. Using a modified injection technique to allow time for local blood flow to return to the basal state, the artifact could be eliminated in 19 of 23 additional subjects. Use of this simple protocol should help avoid misinterpretation of blood flow asymmetry in the assessment of hand disorders

  9. DIVERGENT HORIZONTAL SUB-SURFACE FLOWS WITHIN ACTIVE REGION 11158

    Energy Technology Data Exchange (ETDEWEB)

    Jain, Kiran; Tripathy, S. C.; Hill, F., E-mail: kjain@nso.edu, E-mail: stripathy@nso.edu, E-mail: fhill@nso.edu [National Solar Observatory, 950 N Cherry Avenue, Tucson, AZ 85719 (United States)

    2015-07-20

    We measure the horizontal subsurface flow in a fast emerging active region (AR; NOAA 11158) using the ring-diagram technique and the Helioseismic and Magnetic Imager high spatial resolution Dopplergrams. This AR had a complex magnetic structure and displayed significant changes in morphology during its disk passage. Over a period of six days from 2011 February 11 to 16, the temporal variation in the magnitude of the total velocity is found to follow the trend of magnetic field strength. We further analyze regions of individual magnetic polarity within AR 11158 and find that the horizontal velocity components in these sub-regions have significant variation with time and depth. The leading and trailing polarity regions move faster than the mixed-polarity region. Furthermore, both zonal and meridional components have opposite signs for trailing and leading polarity regions at all depths showing divergent flows within the AR. We also find a sharp decrease in the magnitude of total horizontal velocity in deeper layers around major flares. It is suggested that the re-organization of magnetic fields during flares, combined with the sunspot rotation, decreases the magnitude of horizontal flows or that the flow kinetic energy has been converted into the energy released by flares. After the decline in flare activity and sunspot rotation, the flows tend to follow the pattern of magnetic activity. We also observe less variation in the velocity components near the surface but these tend to increase with depth, further demonstrating that the deeper layers are more affected by the topology of ARs.

  10. High Resolution Model Development to Quantify the Impact of Icebergs on the Stability of the Atlantic Meridional Overturning Circulation

    Energy Technology Data Exchange (ETDEWEB)

    Condron, Alan [Univ. of Massachusetts, Amherst, MA (United States)

    2016-10-18

    In the present-day North Atlantic Ocean, relatively warm and salty water moves northwards from the tropics to the high latitudes, sinks, and returns southward towards the equator as North Atlantic Deep Water, forming the so called Atlantic Meridional Overturning Circulation (AMOC). It has been found that the stability of the AMOC is non-linearly related to the freshwater budget of the North Atlantic. In this way, additional fresh water can be added to the ocean with little impact, until a tipping point is reached that causes the AMOC to suddenly weaken and the Northern Hemisphere to abruptly cool. A great deal of uncertainty still remains over the sensitivity of the AMOC to changes in freshwater discharge as a result of the unrealistic manner in which freshwater has historically been added to climate models. Frequently, freshwater is discharged in ocean models entirely as liquid water, but in reality a large fraction of freshwater entering the ocean is ice calving from marine glaciers (half for Antarctica and two-thirds for Greenland). To more accurately quantify AMOC sensitivity to past and future changes in freshwater input, this project developed a comprehensive iceberg model to more realistically simulate the interaction between the cryosphere and the oceans at high-latitudes. The iceberg model created is written in Fortran90 and designed to scale efficiently on High Performance Computing (HPC) clusters so that tens-of-thousands of icebergs can be simulated at any time. Experiments performed with our model showed that in the Pleistocene there would have been enormous floods of freshwater released into the North Atlantic that would have transported icebergs and meltwater along the entire east coast of the United States, as far south as Florida Keys. In addition, high-resolution, modern-day, model simulations showed that if the Greenland Ice Sheet continues to melt at its current rate then there will be a 6-fold increase in the number of icebergs drifting in the

  11. Mean zonal and meridional accelerations and mean heating induced by solar tides for equinox and solstice conditions

    International Nuclear Information System (INIS)

    Groves, G.V.; Forbes, J.M.

    1985-01-01

    Evaluations are presented of the momentum and energy flux divergences of the diurnal and semidiurnal tidal fields calculated by Forbes from 0 to 400 km altitude. Results are presented in the form of meridional cross-sections from 0 to 78 0 N or S latitude with a 6 0 latitude interval. Comparisons are made with evaluations of the momentum flux divergences of the diurnal tide by Miyahara and good agreement is obtained in the lower thermosphere (below about 130 km) but a large disparity arises in the upper thermosphere. In the lower thermosphere momentum flux divergences of the semidiurnal tide are comparable with those of the diurnal tide and should be included in general circulation calculations of the 90-120 km region. (author)

  12. Temporal Oculomotor Inhibition of Return and Spatial Facilitation of Return in a Visual Encoding Task

    Directory of Open Access Journals (Sweden)

    Steven G Luke

    2013-07-01

    Full Text Available Oculomotor inhibition of return (O-IOR is an increase in saccade latency prior to an eye movement to a recently fixated location compared to other locations. It has been proposed that this temporal O-IOR may have spatial consequences, facilitating foraging by inhibiting return to previously attended regions. In order to test this possibility, participants viewed arrays of objects and of words while their eye movements were recorded. Temporal O-IOR was observed, with equivalent effects for object and word arrays, indicating that temporal O-IOR is an oculomotor phenomenon independent of array content. There was no evidence for spatial inhibition of return. Instead, spatial facilitation of return was observed: Participants were significantly more likely than chance to make return saccades and to refixate just-visited locations. Further, the likelihood of making a return saccade to an object or word was contingent on the amount of time spent viewing that object or word before leaving it. This suggests that, unlike temporal O-IOR, return probability is influenced by cognitive processing. Taken together, these results are inconsistent with the hypothesis that inhibition of return functions as a foraging facilitator. The results also provide strong evidence for a different oculomotor bias that could serve as a foraging facilitator: saccadic momentum, a tendency to repeat the most recently executed saccade program. We suggest that models of visual attention could incorporate saccadic momentum in place of inhibition of return.

  13. The Coupled Mars Dust and Water Cycles: Understanding How Clouds Affect the Vertical Distribution and Meridional Transport of Dust and Water.

    Science.gov (United States)

    Kahre, M. A.

    2015-01-01

    The dust and water cycles are crucial to the current Martian climate, and they are coupled through cloud formation. Dust strongly impacts the thermal structure of the atmosphere and thus greatly affects atmospheric circulation, while clouds provide radiative forcing and control the hemispheric exchange of water through the modification of the vertical distributions of water and dust. Recent improvements in the quality and sophistication of both observations and climate models allow for a more comprehensive understanding of how the interaction between the dust and water cycles (through cloud formation) affects the dust and water cycles individually. We focus here on the effects of clouds on the vertical distribution of dust and water, and how those vertical distributions control the net meridional transport of water. For this study, we utilize observations of temperature, dust and water ice from the Mars Climate Sounder (MCS) on the Mars Reconnaissance Orbiter (MRO) combined with the NASA ARC Mars Global Climate Model (MGCM). We demonstrate that the magnitude and nature of the net meridional transport of water between the northern and southern hemispheres during NH summer is sensitive to the vertical structure of the simulated aphelion cloud belt. We further examine how clouds influence the atmospheric thermal structure and thus the vertical structure of the cloud belt. Our goal is to identify and understand the importance of radiative/dynamic feedbacks due to the physical processes involved with cloud formation and evolution on the current climate of Mars.

  14. Mars Sample Return Architecture Overview

    Science.gov (United States)

    Edwards, C. D.; Vijendran, S.

    2018-04-01

    NASA and ESA are exploring potential concepts for a Sample Retrieval Lander and Earth Return Orbiter that could return samples planned to be collected and cached by the Mars 2020 rover mission. We provide an overview of the Mars Sample Return architecture.

  15. The Croatian Government and Programmes Regarding the Return of War Migrants: between Plans and Realisations – the Experience of The Brod-Posavina County

    Directory of Open Access Journals (Sweden)

    Dragutin Babić

    2002-04-01

    Full Text Available The paper analyses the Croatian government’s programme documents regarding the return and caring for of war migrants. Its aim is to analyse and explain documents, formulated on the national level, as well as those on various local levels in the Brod-Posavina county, and to evaluate their implementation. Return flows began in 1992, after war operations settled down in Croatia. The first returnees were persons whose settlements had not been occupied and who could move into their dwellings straightforwardly. The return of war migrants, as a state strategy, came to the forefront after conclusion of the war in Croatia and Bosnia and Herzegovina and after the signing of the agreement on peaceful reintegration of the Croatian Danubian lands into the Republic of Croatia’s state and legislative system. Croatia recognises the right of all war migrants to return to their homes. Return of dispersed persons and refugees involves various aspects, ranging from state-security problems to pension, economic, social and psychological aspects. The question of return, apart from issues pertaining to the renewal of material structures, includes also the (reconstruction of local communities, which will probably be the most difficult problem to resolve during the process of return. The chances of co-existence of various war migrant groups, especially Croats and Serbs, remain the most important and also the most difficult problem arising in this context. Documents dealing with return are numerous, yet they have been, for the most part, formulated on the national level; much more rarely on the level of local units and return destinations, which is also the main difficulty in regard to the institutional regulation of return flows. Local units mostly act only as intermediaries between international organisations that finance return and individual returnees receiving financial aid or credit. The return of war migrants is mainly financed out of the Republic of Croatia

  16. 26 CFR 20.6018-2 - Returns; person required to file return.

    Science.gov (United States)

    2010-04-01

    ... executor or administrator shall file the return. If there is more than one executor or administrator, the return must be made jointly by all. If there is no executor or administrator appointed, qualified and... decedent situated in the United States is constituted an executor for purposes of the tax (see § 20.2203-1...

  17. Calorific value and EnEV (German Energy Saving Ordinance). Why return flow temperatures are to be planned below the dew point; Brennwert und EnEV. Warum Ruecklauftemperaturen weit unter Taupunkt planen?

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2003-07-01

    Why does the efficiency of a condensing boiler system increase by 5 percent if the temperature is lowered from 45 to 30 degrees centigrade? The condensation temperature of 57-58 degrees centigrade is far higher, so the cold return flow should always remove the complete evaporation heat from the flue gas plumes and transfer it to the incoming flow. Why is this not the case?. [German] Wieso klettert der Wirkungsgrad einer Brennwertkesselanlage bei Absenkung der Kesselruecklauftemperatur von vorher 45 C auf zum Beispiel 30 C um beachtliche 5 Prozent an? Der Wasserdampftaupunkt des Abgases liegt mit 57 C oder 58 C doch in jedem Fall weit oberhalb der 45 C. Der kalte Ruecklauf muesste mithin in beiden Faellen den 58-graedigen Rauchgasschwaden die komplette Verdampfungswaerme entziehen und dem Vorlauf zufuehren - tut er aber nicht. Warum nicht? (orig.)

  18. A simulation of equatorial plasma bubble signatures on the OI 6300A nightglow meridional profile over Brazilian low latitude

    International Nuclear Information System (INIS)

    Nakamura, Y.; Sobral, J.H.A.; Abdu, M.A.

    1981-11-01

    A quantitative interpretation of the meridional propagation of the airglow disturbance for events that have their onsets well westward of the photometer observing longitude, representing the post growth phase of a bubble, is attempted by carrying out a numerical simulation of the phenomenon. Airglow intensity as a function of zenith angle in the photometer scanning range was calculated using electron density profiles perturbed by field aligned plasma bubble whose vertical velocity and electron density depletion profile were determined from a numerical simulation of the nonlinear Rayleigh-Taylor instability under ionospheric conditions that best represented those of the observing period and location. (L.C.) [pt

  19. An Internationally Coordinated Science Management Plan for Samples Returned from Mars

    Science.gov (United States)

    Haltigin, T.; Smith, C. L.

    2015-12-01

    Mars Sample Return (MSR) remains a high priority of the planetary exploration community. Such an effort will undoubtedly be too large for any individual agency to conduct itself, and thus will require extensive global cooperation. To help prepare for an eventual MSR campaign, the International Mars Exploration Working Group (IMEWG) chartered the international Mars Architecture for the Return of Samples (iMARS) Phase II working group in 2014, consisting of representatives from 17 countries and agencies. The overarching task of the team was to provide recommendations for progressing towards campaign implementation, including a proposed science management plan. Building upon the iMARS Phase I (2008) outcomes, the Phase II team proposed the development of an International MSR Science Institute as part of the campaign governance, centering its deliberations around four themes: Organization: including an organizational structure for the Institute that outlines roles and responsibilities of key members and describes sample return facility requirements; Management: presenting issues surrounding scientific leadership, defining guidelines and assumptions for Institute membership, and proposing a possible funding model; Operations & Data: outlining a science implementation plan that details the preliminary sample examination flow, sample allocation process, and data policies; and Curation: introducing a sample curation plan that comprises sample tracking and routing procedures, sample sterilization considerations, and long-term archiving recommendations. This work presents a summary of the group's activities, findings, and recommendations, highlighting the role of international coordination in managing the returned samples.

  20. The role of horizontal thermal advection in regulating wintertime mean and extreme temperatures over the central United States during the past and future

    Science.gov (United States)

    Wang, F.; Vavrus, S. J.

    2017-12-01

    Horizontal temperature advection plays an especially prominent role in affecting winter climate over continental interiors, where both climatological conditions and extreme weather are strongly regulated by transport of remote air masses. Central North America is one such region, and it experienced a major cold-air outbreak (CAO) a few years ago that some have related to amplified Arctic warming. Despite the known importance of dynamics in shaping the winter climate of this sector and the potential for climate change to modify heat transport, limited attention has been paid to the regional impact of thermal advection. Here, we use a reanalysis product and output from the Community Earth System Model's Large Ensemble to quantify the roles of zonal and meridional temperature advection over the central U. S. during winter, both in the late 20th and 21st centuries. We frame our findings as a "tug of war" between opposing influences of the two advection components and between these dynamical forcings vs. thermodynamic changes under greenhouse warming. For example, Arctic amplification leads to much warmer polar air masses, causing a moderation of cold-air advection into the central U. S., yet the model also simulates a wavier mean circulation and stronger northerly flow during CAOs, favoring lower regional temperatures. We also compare the predominant warming effect of zonal advection and overall cooling effect of meridional temperature advection as an additional tug of war. During both historical and future periods, zonal temperature advection is stronger than meridional advection over the Central U. S. The model simulates a future weakening of both zonal and meridional temperature advection, such that westerly flow provides less warming and northerly flow less cooling. On the most extreme warm days in the past and future, both zonal and meridional temperature advection have positive (warming) contributions. On the most extreme cold days, meridional cold air advection

  1. Generalized Couette Poiseuille flow with boundary mass transfer

    Science.gov (United States)

    Marques, F.; Sanchez, J.; Weidman, P. D.

    1998-11-01

    A generalized similarity formulation extending the work of Terrill (1967) for Couette Poiseuille flow in the annulus between concentric cylinders of infinite extent is given. Boundary conditions compatible with the formulation allow a study of the effects of inner and outer cylinder transpiration, rotation, translation, stretching and twisting, in addition to that of an externally imposed constant axial pressure gradient. The problem is governed by [eta], the ratio of inner to outer radii, a Poiseuille number, and nine Reynolds numbers. Single-cylinder and planar problems can be recovered in the limits [eta][rightward arrow]0 and [eta][rightward arrow]1, respectively. Two coupled primary nonlinear equations govern the meridional motion generated by uniform mass flux through the porous walls and the azimuthal motion generated by torsional movement of the cylinders; subsidiary equations linearly slaved to the primary flow govern the effects of cylinder translation, cylinder rotation, and an external pressure gradient. Steady solutions of the primary equations for uniform source/sink flow of strength F through the inner cylinder are reported for 0[less-than-or-eq, slant][eta][less-than-or-eq, slant]1. Asymptotic results corroborating the numerical solutions are found in different limiting cases. For F0 is more complex in that unique solutions are found at low Reynolds numbers, a region of triple solutions exists at moderate Reynolds numbers, and a two-cell solution prevails at large Reynolds numbers. The subsidiary linear equations are solved at [eta]=0.5 to exhibit the effects of cylinder translation, rotation, and an axial pressure gradient on the source/sink flows.

  2. Punctuated Shutdown of Atlantic Meridional Overturning Circulation during Greenland Stadial 1

    Science.gov (United States)

    Hogg, Alan; Southon, John; Turney, Chris; Palmer, Jonathan; Bronk Ramsey, Christopher; Fenwick, Pavla; Boswijk, Gretel; Friedrich, Michael; Helle, Gerhard; Hughen, Konrad; Jones, Richard; Kromer, Bernd; Noronha, Alexandra; Reynard, Linda; Staff, Richard; Wacker, Lukas

    2016-01-01

    The Greenland Stadial 1 (GS-1; ~12.9 to 11.65 kyr cal BP) was a period of North Atlantic cooling, thought to have been initiated by North America fresh water runoff that caused a sustained reduction of North Atlantic Meridional Overturning Circulation (AMOC), resulting in an antiphase temperature response between the hemispheres (the ‘bipolar seesaw’). Here we exploit sub-fossil New Zealand kauri trees to report the first securely dated, decadally-resolved atmospheric radiocarbon (14C) record spanning GS-1. By precisely aligning Southern and Northern Hemisphere tree-ring 14C records with marine 14C sequences we document two relatively short periods of AMOC collapse during the stadial, at ~12,920-12,640 cal BP and 12,050-11,900 cal BP. In addition, our data show that the interhemispheric atmospheric 14C offset was close to zero prior to GS-1, before reaching ‘near-modern’ values at ~12,660 cal BP, consistent with synchronous recovery of overturning in both hemispheres and increased Southern Ocean ventilation. Hence, sustained North Atlantic cooling across GS-1 was not driven by a prolonged AMOC reduction but probably due to an equatorward migration of the Polar Front, reducing the advection of southwesterly air masses to high latitudes. Our findings suggest opposing hemispheric temperature trends were driven by atmospheric teleconnections, rather than AMOC changes. PMID:27194601

  3. Challenges estimating the return period of extreme floods for reinsurance applications

    Science.gov (United States)

    Raven, Emma; Busby, Kathryn; Liu, Ye

    2013-04-01

    Mapping and modelling extreme natural events is fundamental within the insurance and reinsurance industry for assessing risk. For example, insurers might use a 1 in 100-year flood hazard map to set the annual premium of a property, whilst a reinsurer might assess the national scale loss associated with the 1 in 200-year return period for capital and regulatory requirements. Using examples from a range of international flood projects, we focus on exploring how to define what the n-year flood looks like for predictive uses in re/insurance applications, whilst considering challenges posed by short historical flow records and the spatial and temporal complexities of flood. First, we shall explore the use of extreme value theory (EVT) statistics for extrapolating data beyond the range of observations in a marginal analysis. In particular, we discuss how to estimate the return period of historical flood events and explore the impact that a range of statistical decisions have on these estimates. Decisions include: (1) selecting which distribution type to apply (e.g. generalised Pareto distribution (GPD) vs. generalised extreme value distribution (GEV)); (2) if former, the choice of the threshold above which the GPD is fitted to the data; and (3) the necessity to perform a cluster analysis to group flow peaks to temporally represent individual flood events. Second, we summarise a specialised multivariate extreme value model, which combines the marginal analysis above with dependence modelling to generate industry standard event sets containing thousands of simulated, equi-probable floods across a region/country. These events represent the typical range of anticipated flooding across a region and can be used to estimate the largest or most widespread events that are expected to occur. Finally, we summarise how a reinsurance catastrophe model combines the event set with detailed flood hazard maps to estimate the financial cost of floods; both the full event set and also

  4. Valuing companies by cash flow discounting: Ten methods and nine theories

    OpenAIRE

    Fernández , Pablo

    2002-01-01

    This paper is a summarized compendium of all the methods and theories on company valuation using cash flow discounting. The paper shows the ten most commonly used methods for valuing companies by cash flow discounting: 1) free cash flow discounted at the WACC; 2) equity cash flows discounted at the required return to equity; 3) capital cash flows discounted at the WACC before tax; 4) APV (Adjusted Present Value); 5) the business's risk-adjusted free cash flows discounted at the required retur...

  5. PUC fast track nips returns

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    In the first of what it says will be annual cost-of-capital proceedings to set returns on equity and rates of return on rate base for electric utilities, the California Public Utilities Commission (PUC) lowered from 1989 levels the 1990 returns on common equity (ROE) and rates of return (ROR) for the state's four major investor-owned electric utilities. Under this fast-track procedure, by May 8 of every year, utilities will have to file an application for rate adjustments that reflect their projected costs of capital for the following year

  6. The return to foreign aid

    DEFF Research Database (Denmark)

    Dalgaard, Carl-Johan Lars; Hansen, Henrik

    We investigate the marginal productivity of investment across countries. The aim is to estimate the return on investments financed by foreign aid and by domestic resource mobilization, using aggregate data. Both returns are expected to vary across countries and time. Consequently we develop...... a correlated random coefficients model, to estimate the average aggregate return on ‘aid investments’ and ‘domestic investments’. Across different estimators and two different sources for GDP and investment data our findings are remarkably robust; the average gross return on ‘aid investments’ is about 20 per...

  7. The Effects of Voluntary Return Programmes on Migration Flows in the Context of the 1973/74 and 2008/09 Economic Crises

    Directory of Open Access Journals (Sweden)

    Piotr Plewa

    2012-10-01

    Full Text Available The article analyses Spain’s voluntary return policies, including the programme instituted specifically to assist migrants affected by the 2008/09 crisis. Voluntary return policies were implemented in Europe in the context of the 1973/4 crisis. Just like the Western European programmes of the 1970s and the 1980s, the current Spanish voluntary return policies also only elicited the cooperation of small numbers of migrants and countries of origin. The article recommends four broader policy measures to tackle the emerging trend whereby a considerable proportion of migrants will stay in Spain rather than repatriate.

  8. There is no real evidence for a diminishing trend of the Atlantic meridional overturning circulation

    Directory of Open Access Journals (Sweden)

    A. Parker

    2016-01-01

    Full Text Available The Atlantic Meridional Overturning Circulation (AMOC is part of the great ocean “conveyor belt” that circulates heat around the globe. Since the early 2000s, ocean sensors have started to monitor the AMOC, but the measurements are still far from accurate and the time window does not permit the separation of short term variability from a longer term trend. Other works have claimed that global warming is slowing down the AMOC, based on models and proxies of temperatures. Some other observations demonstrate a stable circulation of the oceans. By using tide gauge data complementing recent satellite and ocean sensor observations, the stability of the AMOC is shown to go back to 1860. It is concluded that no available information has the due accuracy and time coverage to show a clear trend outside the inter-annual and multi-decadal variability in the direction of increasing or decreasing strength over the last decades.

  9. Interpreting the implied meridional oceanic energy transport in AMIP

    International Nuclear Information System (INIS)

    Randall, D.A.; Gleckler, P.J.

    1993-09-01

    The Atmospheric Model Intercomparison Project (AMIP) was outlined in Paper No. CLIM VAR 2.3 (entitled open-quote The validation of ocean surface heat fluxes in AMIP') of these proceedings. Preliminary results of AMIP subproject No. 5 were also summarized. In particular, zonally averaged ocean surface heat fluxes resulting from various AMIP simulations were intercompared, and to the extent possible they were validated with uncertainties in observationally-based estimates of surface heat fluxes. The intercomparison is continued in this paper by examining the Oceanic Meridional Energy Transport (OMET) implied by the net surface heat fluxes of the AMIP simulations. As with the surface heat fluxes of the AMIP simulations. As with the surface heat fluxes, the perspective here will be very cursory. The annual mean implied ocean heat transport can be estimated by integrating the zonally averaged net ocean surface heat flux, N sfc , from one pole to the other. In AGCM simulations (and perhaps reality), the global mean N sfc is typically not in exact balance when averaged over one or more years. Because of this, an important assumption must be made about changes in the distribution of energy in the oceans. Otherwise, the integration will yield a non-zero transport at the endpoint of integration (pole) which is not physically realistic. Here the authors will only look at 10-year means of the AMIP runs, and for simplicity they assume that any long term imbalance in the global averaged N sfc will be sequestered (or released) over the global ocean. Tests have demonstrated that the treatment of how the global average energy imbalance is assumed to be distributed is important, especially when the long term imbalances are in excess of 10 W m -2 . However, this has not had a substantial impact on the qualitative features of the implied heat transport of the AMIP simulations examined thus far

  10. Distribution, stock composition and timing, and tagging response of wild Chinook Salmon returning to a large, free-flowing river basin

    Science.gov (United States)

    Eiler, John H.; Masuda, Michele; Spencer, Ted R.; Driscoll, Richard J.; Schreck, Carl B.

    2014-01-01

    Chinook Salmon Oncorhynchus tshawytscha returns to the Yukon River basin have declined dramatically since the late 1990s, and detailed information on the spawning distribution, stock structure, and stock timing is needed to better manage the run and facilitate conservation efforts. A total of 2,860 fish were radio-tagged in the lower basin during 2002–2004 and tracked upriver. Fish traveled to spawning areas throughout the basin, ranging from several hundred to over 3,000 km from the tagging site. Similar distribution patterns were observed across years, suggesting that the major components of the run were identified. Daily and seasonal composition estimates were calculated for the component stocks. The run was dominated by two regional components comprising over 70% of the return. Substantially fewer fish returned to other areas, ranging from 2% to 9% of the return, but their collective contribution was appreciable. Most regional components consisted of several principal stocks and a number of small, spatially isolated populations. Regional and stock composition estimates were similar across years even though differences in run abundance were reported, suggesting that the differences in abundance were not related to regional or stock-specific variability. Run timing was relatively compressed compared with that in rivers in the southern portion of the species’ range. Most stocks passed through the lower river over a 6-week period, ranging in duration from 16 to 38 d. Run timing was similar for middle- and upper-basin stocks, limiting the use of timing information for management. The lower-basin stocks were primarily later-run fish. Although differences were observed, there was general agreement between our composition and timing estimates and those from other assessment projects within the basin, suggesting that the telemetry-based estimates provided a plausible approximation of the return. However, the short duration of the run, complex stock structure, and

  11. Classifying Returns as Extreme

    DEFF Research Database (Denmark)

    Christiansen, Charlotte

    2014-01-01

    I consider extreme returns for the stock and bond markets of 14 EU countries using two classification schemes: One, the univariate classification scheme from the previous literature that classifies extreme returns for each market separately, and two, a novel multivariate classification scheme tha...

  12. A PROPOSED PARADIGM FOR SOLAR CYCLE DYNAMICS MEDIATED VIA TURBULENT PUMPING OF MAGNETIC FLUX IN BABCOCK–LEIGHTON-TYPE SOLAR DYNAMOS

    Energy Technology Data Exchange (ETDEWEB)

    Hazra, Soumitra; Nandy, Dibyendu [Department of Physical Sciences, Indian Institute of Science Education and Research, Kolkata (India)

    2016-11-20

    At present, the Babcock–Leighton flux transport solar dynamo models appear to be the most promising models for explaining diverse observational aspects of the sunspot cycle. The success of these flux transport dynamo models is largely dependent upon a single-cell meridional circulation with a deep equatorward component at the base of the Sun’s convection zone. However, recent observations suggest that the meridional flow may in fact be very shallow (confined to the top 10% of the Sun) and more complex than previously thought. Taken together, these observations raise serious concerns on the validity of the flux transport paradigm. By accounting for the turbulent pumping of magnetic flux, as evidenced in magnetohydrodynamic simulations of solar convection, we demonstrate that flux transport dynamo models can generate solar-like magnetic cycles even if the meridional flow is shallow. Solar-like periodic reversals are recovered even when meridional circulation is altogether absent. However, in this case, the solar surface magnetic field dynamics does not extend all the way to the polar regions. Very importantly, our results demonstrate that the Parker–Yoshimura sign rule for dynamo wave propagation can be circumvented in Babcock–Leighton dynamo models by the latitudinal component of turbulent pumping, which can generate equatorward propagating sunspot belts in the absence of a deep, equatorward meridional flow. We also show that variations in turbulent pumping coefficients can modulate the solar cycle amplitude and periodicity. Our results suggest the viability of an alternate magnetic flux transport paradigm—mediated via turbulent pumping—for sustaining solar-stellar dynamo action.

  13. A PROPOSED PARADIGM FOR SOLAR CYCLE DYNAMICS MEDIATED VIA TURBULENT PUMPING OF MAGNETIC FLUX IN BABCOCK–LEIGHTON-TYPE SOLAR DYNAMOS

    International Nuclear Information System (INIS)

    Hazra, Soumitra; Nandy, Dibyendu

    2016-01-01

    At present, the Babcock–Leighton flux transport solar dynamo models appear to be the most promising models for explaining diverse observational aspects of the sunspot cycle. The success of these flux transport dynamo models is largely dependent upon a single-cell meridional circulation with a deep equatorward component at the base of the Sun’s convection zone. However, recent observations suggest that the meridional flow may in fact be very shallow (confined to the top 10% of the Sun) and more complex than previously thought. Taken together, these observations raise serious concerns on the validity of the flux transport paradigm. By accounting for the turbulent pumping of magnetic flux, as evidenced in magnetohydrodynamic simulations of solar convection, we demonstrate that flux transport dynamo models can generate solar-like magnetic cycles even if the meridional flow is shallow. Solar-like periodic reversals are recovered even when meridional circulation is altogether absent. However, in this case, the solar surface magnetic field dynamics does not extend all the way to the polar regions. Very importantly, our results demonstrate that the Parker–Yoshimura sign rule for dynamo wave propagation can be circumvented in Babcock–Leighton dynamo models by the latitudinal component of turbulent pumping, which can generate equatorward propagating sunspot belts in the absence of a deep, equatorward meridional flow. We also show that variations in turbulent pumping coefficients can modulate the solar cycle amplitude and periodicity. Our results suggest the viability of an alternate magnetic flux transport paradigm—mediated via turbulent pumping—for sustaining solar-stellar dynamo action.

  14. Mitral valve coaptation and its relationship to late diastolic flow: A color Doppler and vector flow map echocardiographic study in normal subjects.

    Science.gov (United States)

    Sherrid, Mark V; Kushner, Josef; Yang, Georgiana; Ro, Richard

    2017-04-01

    Three competing theories about the mechanism of mitral coaptation in normal subjects were evaluated by color Doppler and vector flow mapping (VFM): (1) beginning of ventricular (LV) ejection, (2) "breaking of the jet" of diastolic LV inflow, and (3) returning diastolic vortices impacting the leaflets on their LV surfaces. We analyzed 80 color Doppler frames and 320 VFM measurements. In all 20 normal subjects, coaptation occurred before LV ejection, 78±16 ms before onset. On color Doppler frames the larger anterior, and smaller posterior vortices circle back and, in all cases, strike the ventricular surfaces of the leaflets. On the first closing-begins frame, for the first time, vortex velocity normal to the ventricular surface of the anterior leaflet (AML) is greater than that in the mitral orifice, and the angle of attack of LV vortical flow onto the AML is twice as high as the angle of flow onto the valve in orifice. Thus, at the moment coaptation begins, vortical flow strikes the mitral leaflet with higher velocity, and higher angle of attack than orifice flow, and thus with greater force. According to the "breaking of the jet" theory, one would expect to see de novo LV flow perpendicular to the leaflets beginning after transmitral flow terminates. Instead, the returning continuous LV vortical flow that impacts the valve builds continuously after the P-wave. Late diastolic vortices strike the ventricular surfaces of the mitral leaflets and contribute to valve coaptation, permitted by concomitant decline in transmitral flow. © 2017, Wiley Periodicals, Inc.

  15. PIV Measurements of Flows around the Wind Turbines with a Flanged-Diffuser Shroud

    Institute of Scientific and Technical Information of China (English)

    Kazuhiko Toshimitsu; Koutarou Nishikawa; Wataru Haruki; Shinichi Oono; Manabu Takao; Yuji Ohya

    2008-01-01

    The wind turbines with a flanged-diffuser shroud -so called "wind lens turbine"- are developed as one of high performance wind turbines by Ohya et al. In order to investigate the flow characteristics and flow acceleration, the paper presents the flow velocity measurements of a long-type and a compact-type wind turbines with a flanged-diffuser shroud by particle image velocimetry. In the case of the long type wind turbine, the velocity vec-tors of the inner flow field of the diffuser for turbine blades rotating and no blades rotating are presented at Rey-nolds number, 0.9x105. Furthermore the flow fields between with and without rotating are compared. Through the PIV measurement results, one can realize that the turbine blades rotating affects as suppress the disturbance and the flow separation near the inner wall of the diffuser. The time average velocity vectors are made on the av-erage of the instantaneous velocity data. There are two large vortices in downstream region of the diffuser. One vortex behind the flange acts as suck in wind to the diffuser and raise the inlet flow velocity. Another large vortex appears in downstream. It might be act as blockage vortex of main flow. The large blockage vortex is not clear in the instantaneous velocity vectors, however it exists clearly in the time average flow field. The flow field around the wind turbine with a compact-type flanged-diffuser shroud is also investigated. The flow pattern behind the flange of the compact-type turbine is the same as the long-type one. It means that the effect of flow acceleration is caused by the unsteady vortices behind the flange. The comparison with CFD and PIV results of meridional time-average streamlines after the compact-type diffuser is also presented.

  16. Dynamical relationship between wind speed magnitude and meridional temperature contrast: Application to an interannual oscillation in Venusian middle atmosphere GCM

    Science.gov (United States)

    Yamamoto, Masaru; Takahashi, Masaaki

    2018-03-01

    We derive simple dynamical relationships between wind speed magnitude and meridional temperature contrast. The relationship explains scatter plot distributions of time series of three variables (maximum zonal wind speed UMAX, meridional wind speed VMAX, and equator-pole temperature contrast dTMAX), which are obtained from a Venus general circulation model with equatorial Kelvin-wave forcing. Along with VMAX and dTMAX, UMAX likely increases with the phase velocity and amplitude of a forced wave. In the scatter diagram of UMAX versus dTMAX, points are plotted along a linear equation obtained from a thermal-wind relationship in the cloud layer. In the scatter diagram of VMAX versus UMAX, the apparent slope is somewhat steep in the high UMAX regime, compared with the low UMAX regime. The scatter plot distributions are qualitatively consistent with a quadratic equation obtained from a diagnostic equation of the stream function above the cloud top. The plotted points in the scatter diagrams form a linear cluster for weak wave forcing, whereas they form a small cluster for strong wave forcing. An interannual oscillation of the general circulation forming the linear cluster in the scatter diagram is apparent in the experiment of weak 5.5-day wave forcing. Although a pair of equatorial Kelvin and high-latitude Rossby waves with a same period (Kelvin-Rossby wave) produces equatorward heat and momentum fluxes in the region below 60 km, the equatorial wave does not contribute to the long-period oscillation. The interannual fluctuation of the high-latitude jet core leading to the time variation of UMAX is produced by growth and decay of a polar mixed Rossby-gravity wave with a 14-day period.

  17. The effect of asymmetric information risk on returns of stocks traded on the BM&FBOVESPA

    Directory of Open Access Journals (Sweden)

    Leonardo Souza Siqueira

    Full Text Available ABSTRACT This study sought to analyze information asymmetry in the Brazilian stock market and its relation with the returns required from portfolios through the metrics volume-synchronized probability of informed trading. To do this, the study used actual data from the transactions of 142 stocks on the Brazilian Securities, Commodities and Futures Exchange (BM&FBOVESPA, within the period from May 1, 2014, to May 31, 2016. The results point out a high flow toxicity level in the orders of these stocks. In segment analyses of the stock market listing, data suggest there is no clue that stocks from the theoretically more overt segments have a lower toxicity level of order flows. The justification for this finding lies on the negative correlation observed between the market value of stocks and the toxicity level of orders. To test the effect of asymmetric information risk on stock returns, a factor related to the toxicity level of orders was added to the three-, four-, and five-factor models. Through the GRS test, we observed that the combination of factors that optimize the explanation of returns of the portfolios created was the one taking advantage of the factors market, size, profitability, investment, and information risk. To test the robustness of these results, the Average F-test was used in data simulated by the bootstrap method, and similar estimates were obtained. It was observed that the factor related to the book-to-market index becomes redundant in the national scenario for the models tested. Also, it was found that the factor related to information risk works as a complement to the factor size and that its inclusion leads to an improved performance of the models, indicating a possible explanatory power of information risk on portfolio returns. Therefore, data suggest that information risk is priced in the Brazilian stock market.

  18. QR-GARCH-M Model for Risk-Return Tradeoff in U.S. Stock Returns and Business Cycles

    OpenAIRE

    Nyberg, Henri

    2010-01-01

    In the empirical finance literature findings on the risk return tradeoff in excess stock market returns are ambiguous. In this study, we develop a new QR-GARCH-M model combining a probit model for a binary business cycle indicator and a regime switching GARCH-in-mean model for excess stock market return with the business cycle indicator defining the regime. Estimation results show that there is statistically significant variation in the U.S. excess stock returns over the business cycle. Howev...

  19. Return Migration as Failure or Success?: The Determinants of Return Migration Intentions Among Moroccan Migrants in Europe.

    Science.gov (United States)

    de Haas, Hein; Fokkema, Tineke; Fihri, Mohamed Fassi

    Different migration theories generate competing hypotheses with regard to determinants of return migration. While neoclassical migration theory associates migration to the failure to integrate at the destination, the new economics of labour migration sees return migration as the logical stage after migrants have earned sufficient assets and knowledge and to invest in their origin countries. The projected return is then likely to be postponed for sustained or indefinite periods if integration is unsuccessful. So, from an indication or result of integration failure return is rather seen as a measure of success. Drawing on recent survey data ( N  = 2,832), this article tests these hypotheses by examining the main determinants of return intention among Moroccan migrants across Europe. The results indicate that structural integration through labour market participation, education and the maintenance of economic and social ties with receiving countries do not significantly affect return intentions. At the same time, investments and social ties to Morocco are positively related, and socio-cultural integration in receiving countries is negatively related to return migration intentions. The mixed results corroborate the idea that there is no uniform process of (return) migration and that competing theories might therefore be partly complementary.

  20. 75 FR 76940 - Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic...

    Science.gov (United States)

    2010-12-10

    ... DEPARTMENT OF THE TREASURY Internal Revenue Service 26 CFR Parts 1 and 301 [REG-100194-10] RIN 1545-BJ52 Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic... for ``specified tax return prepares,''. FOR FURTHER INFORMATION CONTACT: Keith L. Brau at (202) 622...

  1. Investment Opportunity, Institutional Ownership, Cash Flow, Company Life Cycle Terhadap Kebijakan Dividen Dan Return Saham

    OpenAIRE

    Wiagustini, Ni Luh Putu

    2009-01-01

    The objective of this research was to examine and to analyze the infl uences of investmentopportunity, cash fl ow, company institutional ownership, and company life cycle stages to dividendpolicy; and the infl uences of dividend policy to investment opportunity, cash fl ow, institutionalownership, and company life cycle stages to share return. The samples used in this research weremanufacturing companies registered at Indonesia Stock Exchange (ISX), who paid dividend regularlywithin the perio...

  2. A Perishable Inventory Model with Return

    Science.gov (United States)

    Setiawan, S. W.; Lesmono, D.; Limansyah, T.

    2018-04-01

    In this paper, we develop a mathematical model for a perishable inventory with return by assuming deterministic demand and inventory dependent demand. By inventory dependent demand, it means that demand at certain time depends on the available inventory at that time with certain rate. In dealing with perishable items, we should consider deteriorating rate factor that corresponds to the decreasing quality of goods. There are also costs involved in this model such as purchasing, ordering, holding, shortage (backordering) and returning costs. These costs compose the total costs in the model that we want to minimize. In the model we seek for the optimal return time and order quantity. We assume that after some period of time, called return time, perishable items can be returned to the supplier at some returning costs. The supplier will then replace them in the next delivery. Some numerical experiments are given to illustrate our model and sensitivity analysis is performed as well. We found that as the deteriorating rate increases, returning time becomes shorter, the optimal order quantity and total cost increases. When considering the inventory-dependent demand factor, we found that as this factor increases, assuming a certain deteriorating rate, returning time becomes shorter, optimal order quantity becomes larger and the total cost increases.

  3. A Study on the Relationship of Earnings and Cash Flows: Evidence of Finance Sector in Iran

    OpenAIRE

    Mahdi Salehi; Mirsohrab Seyedghorbani

    2013-01-01

    The present study is investigating the quality of annual accounting earnings in banking firms that have been listed in Tehran Stock Exchange (TSE) and it evaluates the most important information of accounting that is earnings and cash flows. The study also intends to investigate the relationship between earnings and cash flows regarding their relationship with the expected return of stocks and the extent of informing in the analysis of the inevitable return of stocks. The analyses of data dur...

  4. Physical data generation methodology for return-to-power steam line break analysis

    Energy Technology Data Exchange (ETDEWEB)

    Zee, Sung Kyun; Lee, Chung Chan; Lee, Chang Kue [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1996-02-01

    Current methodology to generate physics data for steamline break accident analysis of CE-type nuclear plant such as Yonggwang Unit 3 is valid only if the core reactivity does not reach the criticality after shutdown. Therefore, the methodology requires tremendous amount of net scram worth, specially at the end of the cycle when moderator temperature coefficient is most negative. Therefore, we need a new methodology to obtain reasonably conservation physics data, when the reactor returns to power condition. Current methodology used ROCS which include only closed channel model. But it is well known that the closed channel model estimates the core reactivity too much negative if core flow rate is low. Therefore, a conservative methodology is presented which utilizes open channel 3D HERMITE model. Current methodology uses ROCS which include only closed channel model. But it is well known that the closed channel model estimates the core reactivity too much negative if core flow rate is low. Therefore, a conservative methodology is presented which utilizes open channel 3D HERMITE model. Return-to-power reactivity credit is produced to assist the reactivity table generated by closed channel model. Other data includes hot channel axial power shape, peaking factor and maximum quality for DNBR analysis. It also includes pin census for radiological consequence analysis. 48 figs., 22 tabs., 18 refs. (Author) .new.

  5. Stock return distribution in the BRICS

    Directory of Open Access Journals (Sweden)

    George Adu

    2015-12-01

    Full Text Available Stock returns in emerging market economies exhibit patterns that are distinctively different from developed countries: returns are noted to be highly volatile and autocorrelated, and long horizon returns are predictable. While these stylized facts are well established, the assumption underlying the distribution of returns is less understood. In particular, the empirical literature continues to rely on the normality assumption as a starting point, and most asset pricing models tend to overstretch this point. This paper questions the rationale behind this supposition and proceeds to test more formally for normality using multivariate joint test for skewness and kurtosis. Additionally, the paper extends the literature by examining a number of empirical regularities for Brazil, Russia, India, China and South Africa (the BRICS for short. Our main findings are that the distribution of stock returns for the BRICS exhibits peakedness with fatter and longer tails, and this is invariant to both the unit of measurement and the time horizon of returns. Volatility clustering is prevalent in all markets, and this decays exponentially for all but Brazil. The relationship between risk and return is found to be significant and risk premiums are prevalent in our sample.

  6. Risk-return of Belgian SRI funds

    OpenAIRE

    Van Liedekerke, Luc; De Moor, Lieven; Vanwalleghem, Dieter

    2007-01-01

    We analyse the risk-return profile of Belgian SRI funds versus conventional investment funds. We apply a four-factor conditional Carhart model to establish whether there are significant differences in risk-return profile between an SRI portfolio and a conventional portfolio and test for learning effects in SRI funds. We show that there is no difference in risk-return profile between SRI and conventional funds. If return is not the problem, then what is it that limits the development of an SRI...

  7. ISS Payload Racks Automated Flow Control Calibration Method

    Science.gov (United States)

    Simmonds, Boris G.

    2003-01-01

    Payload Racks utilize MTL and/or LTL station water for cooling of payloads and avionics. Flow control range from valves of fully closed, to up to 300 Ibmhr. Instrument accuracies are as high as f 7.5 Ibm/hr for flow sensors and f 3 Ibm/hr for valve controller, for a total system accuracy of f 10.5 Ibm/hr. Improved methodology was developed, tested and proven that reduces accuracy of the commanded flows to less than f 1 Ibmhr. Uethodology could be packed in a "calibration kit" for on- orbit flow sensor checkout and recalibration, extending the rack operations before return to earth. -

  8. 7 CFR 3560.305 - Return on investment.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Return on investment. 3560.305 Section 3560.305... AGRICULTURE DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Financial Management § 3560.305 Return on investment. (a) Borrower's return on investment. Borrowers may receive a return on their investment (ROI) in...

  9. Characteristics of donors who do or do not return to give blood and barriers to their return

    Science.gov (United States)

    Wevers, Anne; Wigboldus, Daniël H.J.; de Kort, Wim L.A.M.; van Baaren, Rick; Veldhuizen, Ingrid J.T.

    2014-01-01

    Background In the Netherlands about 50% of whole blood donors return to give blood after an invitation to donate. This study aimed to investigate the characteristics of donor return behaviour and to gain insight into the barriers to blood donation reported by the donors themselves. Materials and methods A total of 4,901 whole blood donors were invited to donate in week 39 of 2009. Barriers mentioned by donors who informed the blood bank for not donating were registered for 1 month. Logistic regression analyses assessed relevant characteristics of return behaviour, such as age and blood type, in men and women separately. Results Of the invited donors, 55% returned to give a donation, whereas 45% did not return. Male donors were more likely to return when they were older, had a higher previous return rate and had no past deferrals. The same pattern was found among women, but was less strong. The main barriers were: time constraints (35%), preference to postpone donation due to general physical problems although being eligible to donate (29%), and being ineligible to donate due to medical deferral criteria (9%). Discussion Specific donor characteristics are associated with return behaviour. Not donating due to time constraints could mean that donors do not feel the urgency of donating blood. Interventions targeted to increase commitment among specific donor groups should be tested further. PMID:23522891

  10. Money growth and aggregate stock returns

    OpenAIRE

    Böing, Tobias; Stadtmann, Georg

    2016-01-01

    We empirically evaluate the predictive power of money growth measured by M2 for stock returns of the S&P 500 index. We use monthly US data and predict multiperiod returns over 1, 3, and 5 years with long-horizon regressions. In-sample regressions show that money growth is useful for predicting returns. Higher recent money growth has a significantly negative effect on subsequent returns of the S&P 500. An out-of-sample analysis shows that a simple model with money growth as a single predictor ...

  11. Poetic Return in Afghanistan Persian Poem

    Directory of Open Access Journals (Sweden)

    Esmaeil Shafagh

    2012-11-01

    Full Text Available Abstract Poetic return movement was started by a group of poets like Moshtagh and Shole Esfehani in the second half of 12 century. Their goal was restoring Persian poem and deliverance of Hindi style decline. Esfahan’s poets initiative was considered only in Iran but in other Persian language and literature areas like India, Afghanistan and Transoxiana it was ignored. After the failure of constitutional Movement in Afghanistan, motion similar poetic return was happened that caused poetic themes, which had gone towards modernism, return to Hindi style again.The present paper attempts to analyze the poetic atmosphere in Afghanistan synchronous the poetic return movement in Iran and investigate socio- political backgrounds of return to Hindi style in Afghanistan after constitution failure.

  12. Spatial linear flows of finite length with nonuniform intensity distribution

    Directory of Open Access Journals (Sweden)

    Mikhaylov Ivan Evgrafovich

    2014-02-01

    Full Text Available Irrotational flows produced by spatial linear flows of finite length with different uneven lows of discharge over the flow length are represented in cylindrical coordinate system. Flows with the length 2a are placed in infinite space filled with ideal (inviscid fluid. In “А” variant discharge is fading linearly downward along the length of the flow. In “B” variant in upper half of the flow (length a discharge is fading linearly downward, in lower half of the flow discharge is fading linearly from the middle point to lower end. In “C” variant discharge of the flow is growing linearly from upper and lower ends to middle point.Equations for discharge distribution along the length of the flow are provided for each variant. Equations consist of two terms and include two dimensional parameters and current coordinate that allows integrating on flow length. Analytical expressions are derived for speed potential functions and flow speed components for flow speeds produced by analyzed flows. These analytical expressions consist of dimensional parameters of discharge distribution patterns along the length of the flow. Flow lines equation (meridional sections of flow surfaces for variants “A”, “B”, “C” is unsolvable in quadratures. Flow lines plotting is proposed to be made by finite difference method. Equations for flow line plotting are provided for each variant. Calculations of these equations show that the analyzed flows have the following flow lines: “A” has confocal hyperbolical curves, “B” and “C” have confocal hyperboles. Flow surfaces are confocal hyperboloids produced by rotation of these hyperboles about the axis passing through the flows. In “A” variant the space filled with fluid is separated by vividly horizontal flow surface in two parts. In upper part that includes the smaller part of the flow length flow lines are oriented downward, in lower part – upward. The equation defining coordinate of

  13. Cash Flow and Discount Rate Risk in Up and Down Markets: What is actually priced?

    NARCIS (Netherlands)

    Botshekan, M.; Kraeussl, R.G.W.; Lucas, A.

    2012-01-01

    We test whether asymmetric preferences for losses versus gains affect the prices of cash flow versus discount rate risk. We construct a return decomposition distinguishing cash flow and discount rate betas in up and down markets. Using U.S. data, we find that downside cash flow and discount rate

  14. Common Factors in International Bond Returns

    NARCIS (Netherlands)

    Driessen, J.J.A.G.; Melenberg, B.; Nijman, T.E.

    2000-01-01

    In this paper we estimate and interpret the factors that jointly determine bond returns of different maturities in the US, Germany and Japan.We analyze both currency-hedged and unhedged bond returns.For currency-hedged bond returns, we find that five factors explain 96.5% of the variation of bond

  15. Return-to-work coordination programmes for improving return to work in workers on sick leave.

    Science.gov (United States)

    Vogel, Nicole; Schandelmaier, Stefan; Zumbrunn, Thomas; Ebrahim, Shanil; de Boer, Wout El; Busse, Jason W; Kunz, Regina

    2017-03-30

    To limit long-term sick leave and associated consequences, insurers, healthcare providers and employers provide programmes to facilitate disabled people's return to work. These programmes include a variety of coordinated and individualised interventions. Despite the increasing popularity of such programmes, their benefits remain uncertain. We conducted a systematic review to determine the long-term effectiveness of return-to-work coordination programmes compared to usual practice in workers at risk for long-term disability. To assess the effects of return-to-work coordination programmes versus usual practice for workers on sick leave or disability. We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 11), MEDLINE, Embase, CINAHL and PsycINFO up to 1 November 2016. We included randomised controlled trials (RCTs) that enrolled workers absent from work for at least four weeks and randomly assigned them to return-to-work coordination programmes or usual practice. Two review authors independently screened titles, abstracts and full-text articles for study eligibility; extracted data; and assessed risk of bias from eligible trials. We contacted authors for additional data where required. We conducted random-effects meta-analyses and used the GRADE approach to rate the quality of the evidence. We identified 14 studies from nine countries that enrolled 12,568 workers. Eleven studies focused on musculoskeletal problems, two on mental health and one on both. Most studies (11 of 14) followed workers 12 months or longer. Risk of bias was low in 10 and high in 4 studies, but findings were not sensitive to their exclusion.We found no benefits for return-to-work coordination programmes on return-to-work outcomes.For short-term follow-up of six months, we found no effect on time to return to work (hazard ratio (HR) 1.32, 95% confidence interval (CI) 0.93 to 1.88, low-quality evidence), cumulative sickness absence (mean difference (MD) -16.18 work

  16. Accounting- versus economic-based rates of return: implications for profitability measures in the pharmaceutical industry.

    Science.gov (United States)

    Skrepnek, Grant H

    2004-01-01

    Accounting-based profits have indicated that pharmaceutical firms have achieved greater returns relative to other sectors. However, partially due to the theoretically inappropriate reporting of research and development (R&D) expenditures according to generally accepted accounting principles, evidence suggests that a substantial and upward bias is present in accounting-based rates of return for corporations with high levels of intangible assets. Given the intensity of R&D in pharmaceutical firms, accounting-based profit metrics in the drug sector may be affected to a greater extent than other industries. The aim of this work was to address measurement issues associated with corporate performance and factors that contribute to the bias within accounting-based rates of return. Seminal and broadly cited works on the subject of accounting- versus economic-based rates of return were reviewed from the economic and finance literature, with an emphasis placed on issues and scientific evidence directly related to the drug development process and pharmaceutical industry. With international convergence and harmonization of accounting standards being imminent, stricter adherence to theoretically sound economic principles is advocated, particularly those based on discounted cash-flow methods. Researchers, financial analysts, and policy makers must be cognizant of the biases and limitations present within numerous corporate performance measures. Furthermore, the development of more robust and valid economic models of the pharmaceutical industry is required to capture the unique dimensions of risk and return of the drug development process. Empiric work has illustrated that estimates of economic-based rates of return range from approximately 2 to approximately 11 percentage points below various accounting-based rates of return for drug companies. Because differences in the nature of risk and uncertainty borne by drug manufacturers versus other sectors make comparative assessments

  17. E-business and circular supply chains : Increased business opportunities by IT-based customer oriented return-flow management

    NARCIS (Netherlands)

    Krikke, H.R.; van Nunen, J.A.E.E.; Zuidwijk, R.A.; Kuik, R.

    2003-01-01

    This paper deals with the application of IT in circular supply chains (CSCs). We consider information on the installed base critical, and present an illustrative example. Next we discuss a framework of different kinds of value contained in a return, and IT-applications useful in supporting its

  18. 26 CFR 301.6103(n)-1 - Disclosure of returns and return information in connection with written contracts or agreements...

    Science.gov (United States)

    2010-04-01

    ... administration purposes. 301.6103(n)-1 Section 301.6103(n)-1 Internal Revenue INTERNAL REVENUE SERVICE... and Returns Returns and Records § 301.6103(n)-1 Disclosure of returns and return information in... administration purposes. (a) General rule. (1) Pursuant to the provisions of section 6103(n) of the Internal...

  19. ASPECTOS SOCIO-ECONÓMICOS DE LAS MIGRACIONES RECIENTES EN ESPAÑA EN EL CONTEXTO DE LA EUROPA MERIDIONAL. ELEMENTOS PARA UNA POSIBLE TEORÍA

    Directory of Open Access Journals (Sweden)

    Gaetano Ferrieri

    1996-01-01

    Full Text Available Se analizan la s características geográficas y la s implicaciones socio-económicas de los recientes flujos inmigratorios que re cibe España, relacionando las tendencias econó- micas y las tendencias migratorias; el ejempl o español se estudia en el contexto de la Europa meridional, como nueva meta de las migraciones internacionales. El estudio concluye con la propuesta de una posible te oría sobre el ciclo migratorio-económico.

  20. Plausible Effect of Weather on Atlantic Meridional Overturning Circulation with a Coupled General Circulation Model

    Science.gov (United States)

    Liu, Zedong; Wan, Xiuquan

    2018-04-01

    The Atlantic meridional overturning circulation (AMOC) is a vital component of the global ocean circulation and the heat engine of the climate system. Through the use of a coupled general circulation model, this study examines the role of synoptic systems on the AMOC and presents evidence that internally generated high-frequency, synoptic-scale weather variability in the atmosphere could play a significant role in maintaining the overall strength and variability of the AMOC, thereby affecting climate variability and change. Results of a novel coupling technique show that the strength and variability of the AMOC are greatly reduced once the synoptic weather variability is suppressed in the coupled model. The strength and variability of the AMOC are closely linked to deep convection events at high latitudes, which could be strongly affected by the weather variability. Our results imply that synoptic weather systems are important in driving the AMOC and its variability. Thus, interactions between atmospheric weather variability and AMOC may be an important feedback mechanism of the global climate system and need to be taken into consideration in future climate change studies.

  1. Closing the Loop : Reverse supply chain management andproduct return processes in electronics retailing

    OpenAIRE

    Gorskova, Julija; Ortega, Edrion

    2012-01-01

    Abstract Problem There is a gap in the knowledge concerning reverse product flows due to a lack of research and empirical data in the field of reverse supply chain management in general. Furthermore, more research is needed to investigate the factors influencing the decision making process regarding the right reverse supply chain recovery option choice for companies in order to close the supply chain loop. Processing product returns has become a critical activity for organisations as the volu...

  2. Sustainable Mars Sample Return

    Science.gov (United States)

    Alston, Christie; Hancock, Sean; Laub, Joshua; Perry, Christopher; Ash, Robert

    2011-01-01

    The proposed Mars sample return mission will be completed using natural Martian resources for the majority of its operations. The system uses the following technologies: In-Situ Propellant Production (ISPP), a methane-oxygen propelled Mars Ascent Vehicle (MAV), a carbon dioxide powered hopper, and a hydrogen fueled balloon system (large balloons and small weather balloons). The ISPP system will produce the hydrogen, methane, and oxygen using a Sabatier reactor. a water electrolysis cell, water extracted from the Martian surface, and carbon dioxide extracted from the Martian atmosphere. Indigenous hydrogen will fuel the balloon systems and locally-derived methane and oxygen will fuel the MAV for the return of a 50 kg sample to Earth. The ISPP system will have a production cycle of 800 days and the estimated overall mission length is 1355 days from Earth departure to return to low Earth orbit. Combining these advanced technologies will enable the proposed sample return mission to be executed with reduced initial launch mass and thus be more cost efficient. The successful completion of this mission will serve as the next step in the advancement of Mars exploration technology.

  3. Climate Prediction Center (CPC) Northern and Southern Hemisphere Blocking Index

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Atmospheric blocking is commonly referred to as the situation when the normal zonal flow is interrupted by strong and persistent meridional flow. The normal eastward...

  4. A Compound Detection System Based on Ultrasonic Flow Rate and Concentration

    OpenAIRE

    Qing-Hui WANG; Fang MU; Li-Feng WEI

    2014-01-01

    This paper proposes a new detection system for monitoring gas concentration and flow rate. Velocity difference of ultrasonic wave in bi-directional propagation in measured gas is recorded and utilized for computing the online gas concentration and flow rate. Meanwhile, the temperature compensation, return signal processing and error analysis algorithms are applied to improve the accuracy. The experimental results show that, compared with the single sensor measurement of gas flow rate or conce...

  5. Turbulent Flow Modification With Thermoacoustic Waves for Separation Control

    Science.gov (United States)

    2017-08-24

    respectively. At the outlet, the time-average flow is set to be the target state of the sponge zone. In this section, the effects of momentum thickness...Turbulent Flow Modification With Thermoacoustic Waves For Separation Control The views, opinions and/or findings contained in this report are those...currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. Florida State University Sponsored Research Administration 874

  6. The 226Ra isotope activities in ground water samples drawn of two wells from the Meridional Pluton, Morungaba Granitoids, eastern Sao Paulo State; Atividades do 226Ra em aguas subterraneas extraidas de dois pocos localizados no pluton meridional, granitoides de Morungaba, SP

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, Fabio de Oliveira; Silva Junior, Mario Goncalves da; Bertolla, Luciana; Ribeiro, Fernando Brenha [Sao Paulo Univ., SP (Brazil). Inst. de Astronomia, Geofisica e Ciencias Atmosfericas. Dept. de Geofisica]. E-mail: brenha@iag.usp.br

    2005-07-01

    The 226Ra activities, both in solution and associated with suspended solids, were measured in ground water samples drawn from two wells drilled in a fractured granitic aquifer from the Meridional Pluton, Morungaba Granitoids, eastern Sao Paulo State. The 226Ra isotope activities were measured in a sequence of samples collected about one month apart between March, 2003 and April 2004. The 226Ra activities were measured by radon gas emanometry. The mean dissolved 226Ra activity concentration activities observed in the two wells were (44.9 {+-} 7.1) mBq/L and (51.6 {+-} 8.8) mBq/L. The 226Ra activity of the suspend solids in a liter of these waters varied between (0,6 {+-} 0,1) mBq and (13 {+-} 1) mBq, respectively. (author)

  7. Utility allowed returns and market extremes

    International Nuclear Information System (INIS)

    Murry, D.A.; Nan, G.D.; Harrington, B.M.

    1993-01-01

    In recent years interest rates have fluctuated from exceptionally high levels in the early 1980s to their current levels, the lowest in two decades. Observers and analysts generally have assumed that allowed returns by regulatory commissions follow the movement of interest rates; indeed some analysts use a risk premium method to estimate the cost of common equity, assuming a constant and linear relationship between interest rates and the cost of common equity. That suggests we could expect a relatively stable relationship between interest rates and allowed returns, as well. However, a simple comparison of allowed returns and interest rates shows that this is not the case in recent years. The relationship between market interest rates and the returns allowed by commissions varies and is obviously a great deal more complicated. Empirically, there appears to be only a narrow range where market interest rates significantly affect the allowed returns on common stock set by state commissions, at least for electric and combination utilities. If rates are at historically low levels, allowed returns based largely on market rates will hasten subsequent rate filings, and commissions appear to look beyond the low rate levels. Conversely, it appears that regulators do not let historically high market rates determine allowed returns either. At either high or low interest levels, caution seems to be the policy

  8. Return to sports after shoulder arthroplasty

    Science.gov (United States)

    Johnson, Christine C; Johnson, Daniel J; Liu, Joseph N; Dines, Joshua S; Dines, David M; Gulotta, Lawrence V; Garcia, Grant H

    2016-01-01

    Many patients prioritize the ability to return to sports following shoulder replacement surgeries, including total shoulder arthroplasty (TSA), reverse total shoulder arthroplasty (RTSA), and hemiarthroplasty (HA). While activity levels after hip and knee replacements have been well-established in the literature, studies on this topic in the field of shoulder arthroplasty are relatively limited. A review of the literature regarding athletic activity after shoulder arthroplasty was performed using the PubMed database. All studies relevant to shoulder arthroplasty and return to sport were included. The majority of patients returned to their prior level of activity within six months following TSA, RTSA, and shoulder HA. Noncontact, low demand activities are permitted by most surgeons postoperatively and generally have higher return rates than contact sports or high-demand activities. In some series, patients reported an improvement in their ability to participate in sports following the arthroplasty procedure. The rates of return to sports following TSA (75%-100%) are slightly higher than those reported for HA (67%-76%) and RTSA (75%-85%). Patients undergoing TSA, RTSA, and shoulder HA should be counseled that there is a high probability that they will be able to return to their preoperative activity level within six months postoperatively. TSA has been associated with higher rates of return to sports than RTSA and HA, although this may reflect differences in patient population or surgical indication. PMID:27672564

  9. 26 CFR 301.6019-1 - Gift tax returns.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Gift tax returns. 301.6019-1 Section 301.6019-1... ADMINISTRATION PROCEDURE AND ADMINISTRATION Information and Returns Returns and Records § 301.6019-1 Gift tax returns. For provisions relating to requirement of gift tax returns, see §§ 25.6019-1 to 25.6019-4...

  10. Stock Returns and Risk: Evidence from Quantile

    Directory of Open Access Journals (Sweden)

    Thomas C. Chiang

    2012-12-01

    Full Text Available This paper employs weighted least squares to examine the risk-return relation by applying high-frequency data from four major stock indexes in the US market and finds some evidence in favor of a positive relation between the mean of the excess returns and expected risk. However, by using quantile regressions, we find that the risk-return relation moves from negative to positive as the returns’ quantile increases. A positive risk-return relation is valid only in the upper quantiles. The evidence also suggests that intraday skewness plays a dominant role in explaining the variations of excess returns.

  11. Forces on zonal flows in tokamak core turbulence

    International Nuclear Information System (INIS)

    Hallatschek, K.; Itoh, K.

    2005-01-01

    The saturation of stationary zonal flows (ZF) in the core of a tokamak has been analyzed in numerical fluid turbulence computer studies. The model was chosen to properly represent the kinetic global plasma flows, i.e., undamped stationary toroidal or poloidal flows and Landau damped geodesic acoustic modes. Reasonable agreement with kinetic simulations in terms of magnitude of transport and occurrence of the Dimits shift was verified. Contrary to common perception, in the final saturated state of turbulence and ZFs, the customary perpendicular Reynolds stress continues to drive the ZFs. The force balance is established by the essentially quasilinear parallel Reynolds stress acting on the parallel return flows required by incompressibility. (author)

  12. Return to Golf After Lumbar Fusion.

    Science.gov (United States)

    Shifflett, Grant D; Hellman, Michael D; Louie, Philip K; Mikhail, Christopher; Park, Kevin U; Phillips, Frank M

    Spinal fusion surgery is being increasingly performed, yet few studies have focused on return to recreational sports after lumbar fusion and none have specifically analyzed return to golf. Most golfers successfully return to sport after lumbar fusion surgery. Case series. Level 4. All patients who underwent 1- or 2-level primary lumbar fusion surgery for degenerative pathologies performed by a single surgeon between January 2008 and October 2012 and had at least 1-year follow-up were included. Patients completed a specifically designed golf survey. Surveys were mailed, given during follow-up clinic, or answered during telephone contact. A total of 353 patients met the inclusion and exclusion criteria, with 200 responses (57%) to the questionnaire producing 34 golfers. The average age of golfers was 57 years (range, 32-79 years). In 79% of golfers, preoperative back and/or leg pain significantly affected their ability to play golf. Within 1 year from surgery, 65% of patients returned to practice and 52% returned to course play. Only 29% of patients stated that continued back/leg pain limited their play. Twenty-five patients (77%) were able to play the same amount of golf or more than before fusion surgery. Of those providing handicaps, 12 (80%) reported the same or an improved handicap. More than 50% of golfers return to on-course play within 1 year of lumbar fusion surgery. The majority of golfers can return to preoperative levels in terms of performance (handicap) and frequency of play. This investigation offers insight into when golfers return to sport after lumbar fusion surgery and provides surgeons with information to set realistic expectations postoperatively.

  13. Lymphatic System Flows

    Science.gov (United States)

    Moore, James E., Jr.; Bertram, Christopher D.

    2018-01-01

    The supply of oxygen and nutrients to tissues is performed by the blood system and involves a net leakage of fluid outward at the capillary level. One of the principal functions of the lymphatic system is to gather this fluid and return it to the blood system to maintain overall fluid balance. Fluid in the interstitial spaces is often at subatmospheric pressure, and the return points into the venous system are at pressures of approximately 20 cmH2O. This adverse pressure difference is overcome by the active pumping of collecting lymphatic vessels, which feature closely spaced one-way valves and contractile muscle cells in their walls. Passive vessel squeezing causes further pumping. The dynamics of lymphatic pumping have been investigated experimentally and mathematically, revealing complex behaviors that indicate that the system performance is robust against minor perturbations in pressure and flow. More serious disruptions can lead to incurable swelling of tissues called lymphedema.

  14. Delta flow: An accurate, reliable system for detecting kicks and loss of circulation during drilling

    Energy Technology Data Exchange (ETDEWEB)

    Speers, J.M.; Gehrig, G.F.

    1987-12-01

    A system to monitor drilling-fluid flow rate has been developed that detects kicks and lost returns in floating, fixed-platform, and land-base drilling operations. The system uses flowmeters that monitor the flow rates of drilling fluids entering the borehole through the standpipe and leaving the well through the return flowline. These readings are processed in a computer-based, data-acquisition system to form a filtered delta-flow signal that identified the occurrence of downhole fluid gains or losses. The system is designed to trip an alarm when a gain or loss exceeds 25 gal/min (1.6 dm/sup 3//s), even in a floating drilling environment. This sensitivity will generally keep gains or losses to less than 5 bbl (0.8 m/sup 3/).

  15. Does Aggregated Returns Disclosure Increase Portfolio Risk Taking?

    Science.gov (United States)

    Beshears, John; Choi, James J; Laibson, David; Madrian, Brigitte C

    2017-06-01

    Many experiments have found that participants take more investment risk if they see returns less frequently, see portfolio-level returns (rather than each individual asset's returns), or see long-horizon (rather than one-year) historical return distributions. In contrast, we find that such information aggregation treatments do not affect total equity investment when we make the investment environment more realistic than in prior experiments. Previously documented aggregation effects are not robust to changes in the risky asset's return distribution or the introduction of a multi-day delay between portfolio choice and return realizations.

  16. Mechanisms for decadal scale variability in a simulated Atlantic meridional overturning circulation

    Energy Technology Data Exchange (ETDEWEB)

    Medhaug, I.; Eldevik, T.; Furevik, T. [University of Bergen, Geophysical Institute, Bergen (Norway); Bjerknes Centre for Climate Research, Bergen (Norway); Langehaug, H.R. [Nansen Environmental and Remote Sensing Center, Bergen (Norway); Bjerknes Centre for Climate Research, Bergen (Norway); Bentsen, M. [Uni Bjerknes Centre, Uni Research, Bergen (Norway); Bjerknes Centre for Climate Research, Bergen (Norway)

    2012-07-15

    Variability in the Atlantic Meridional Overturning Circulation (AMOC) has been analysed using a 600-year pre-industrial control simulation with the Bergen Climate Model. The typical AMOC variability has amplitudes of 1 Sverdrup (1 Sv = 10{sup 6} m{sup 3} s{sup -1}) and time scales of 40-70 years. The model is reproducing the observed dense water formation regions and has very realistic ocean transports and water mass distributions. The dense water produced in the Labrador Sea (1/3) and in the Nordic Seas, including the water entrained into the dense overflows across the Greenland-Scotland Ridge (GSR; 2/3), are the sources of North Atlantic Deep Water (NADW) forming the lower limb of the AMOC's northern overturning. The variability in the Labrador Sea and the Nordic Seas convection is driven by decadal scale air-sea fluxes in the convective region that can be related to opposite phases of the North Atlantic Oscillation. The Labrador Sea convection is directly linked to the variability in AMOC. Linkages between convection and water mass transformation in the Nordic Seas are more indirect. The Scandinavian Pattern, the third mode of atmospheric variability in the North Atlantic, is a driver of the ocean's poleward heat transport (PHT), the overall constraint on northern water mass transformation. Increased PHT is both associated with an increased water mass exchange across the GSR, and a stronger AMOC. (orig.)

  17. PENGARUH MODAL INTELEKTUAL TERHADAP MANAJEMEN LABA RIIL DAN FUTURE STOCK RETURNS

    Directory of Open Access Journals (Sweden)

    Tendy Wato

    2017-02-01

    Full Text Available This study aims to examine the influence of Intellectual Capital (IC on Real Earnings Management (MR and  Future Stock Returns (FSR in the manufacturing companies listed in Indonesia Stock Exchange (IDX.  The data used was obtained using multiple  regression of 27 companies manufacturing for the period 2007 to 2013. Model IC using VAICTM of Pulic (2000, Model Manajemen Laba Riil (MR of Roychowdhury (2006 and the FSR of Sloan (1996. Model analysis of the test data is performed by Multiple Regression. The results showed a partial effect on the IC to MR- PROD, MR-DISX and MR-CFO. IC has affect the FSR significantly. The overall results of this study support the theory resourced-based and knowledge-based. Research of Intellectual Capital (IC is a new one in Indonesia, so that the data associated with the IC is still difficult to obtain. Also there is no official standard referenced in particular the Financial Accounting Standards (IFRSs Indonesia in calculating the IC. The paper shows that intellectual capital is an important element affecting the future stock returns with real earnings management as intervening. The paper’s finding suggest that it is necessary to improve the transparency of the accounting information, so as to reduce  real earnings management,  especially in cash flow operation and improve earnings quality to some extent, which provides valuable reference for the company’s decision. This paper extends prior research by addressing the potential effects of IC on future stock returns with real earnings management as intervening.  The findings reported in this paper provide novel insights to the empirical financial accounting literature. Keyword: Intellectual  capital, real earning management, future stock returns.

  18. Nuclear magnetic resonance characterization of the stationary dynamics of partially saturated media during steady-state infiltration flow

    Science.gov (United States)

    Rassi, Erik M.; Codd, Sarah L.; Seymour, Joseph D.

    2011-01-01

    Flow in porous media and the resultant hydrodynamics are important in fields including but not limited to the hydrology, chemical, medical and petroleum industries. The observation and understanding of the hydrodynamics in porous media are critical to the design and optimal utilization of porous media, such as those seen in trickle-bed reactors, medical filters, subsurface flows and carbon sequestration. Magnetic resonance (MR) provides for a non-invasive technique that can probe the hydrodynamics on pore and bulk scale lengths; many previous works have characterized fully saturated porous media, while rapid MR imaging (MRI) methods in particular have previously been applied to partially saturated flows. We present time- and ensemble-averaged MR measurements to observe the effects on a bead pack partially saturated with air under flowing water conditions. The 10 mm internal diameter bead pack was filled with 100 μm borosilicate glass beads. Air was injected into the bead pack as water flowed simultaneously through the sample at 25 ml h-1. The initial partially saturated state was characterized with MRI density maps, free induction decay (FID) experiments, propagators and velocity maps before the water flow rate was increased incrementally from 25 to 500 ml h-1. After the maximum flow rate of 500 ml h-1, the MRI density maps, FID experiments, propagators and velocity maps were repeated and compared to the data taken before the maximum flow rate. This work shows that a partially saturated single-phase flow has global flow dynamics that return to characteristic flow statistics once a steady-state high flow rate has been reached. This high flow rate pushed out a significant amount of the air in the bead pack and caused the return of a preferential flow pattern. Velocity maps indicated that local flow statistics were not the same for the before and after blow out conditions. It has been suggested and shown previously that a flow pattern can return to

  19. Nuclear magnetic resonance characterization of the stationary dynamics of partially saturated media during steady-state infiltration flow

    International Nuclear Information System (INIS)

    Rassi, Erik M; Codd, Sarah L; Seymour, Joseph D

    2011-01-01

    Flow in porous media and the resultant hydrodynamics are important in fields including but not limited to the hydrology, chemical, medical and petroleum industries. The observation and understanding of the hydrodynamics in porous media are critical to the design and optimal utilization of porous media, such as those seen in trickle-bed reactors, medical filters, subsurface flows and carbon sequestration. Magnetic resonance (MR) provides for a non-invasive technique that can probe the hydrodynamics on pore and bulk scale lengths; many previous works have characterized fully saturated porous media, while rapid MR imaging (MRI) methods in particular have previously been applied to partially saturated flows. We present time- and ensemble-averaged MR measurements to observe the effects on a bead pack partially saturated with air under flowing water conditions. The 10 mm internal diameter bead pack was filled with 100 μm borosilicate glass beads. Air was injected into the bead pack as water flowed simultaneously through the sample at 25 ml h -1 . The initial partially saturated state was characterized with MRI density maps, free induction decay (FID) experiments, propagators and velocity maps before the water flow rate was increased incrementally from 25 to 500 ml h -1 . After the maximum flow rate of 500 ml h -1 , the MRI density maps, FID experiments, propagators and velocity maps were repeated and compared to the data taken before the maximum flow rate. This work shows that a partially saturated single-phase flow has global flow dynamics that return to characteristic flow statistics once a steady-state high flow rate has been reached. This high flow rate pushed out a significant amount of the air in the bead pack and caused the return of a preferential flow pattern. Velocity maps indicated that local flow statistics were not the same for the before and after blow out conditions. It has been suggested and shown previously that a flow pattern can return to similar

  20. Statistics of return intervals between long heartbeat intervals and their usability for online prediction of disorders

    International Nuclear Information System (INIS)

    Bogachev, Mikhail I; Bunde, Armin; Kireenkov, Igor S; Nifontov, Eugene M

    2009-01-01

    We study the statistics of return intervals between large heartbeat intervals (above a certain threshold Q) in 24 h records obtained from healthy subjects. We find that both the linear and the nonlinear long-term memory inherent in the heartbeat intervals lead to power-laws in the probability density function P Q (r) of the return intervals. As a consequence, the probability W Q (t; Δt) that at least one large heartbeat interval will occur within the next Δt heartbeat intervals, with an increasing elapsed number of intervals t after the last large heartbeat interval, follows a power-law. Based on these results, we suggest a method of obtaining a priori information about the occurrence of the next large heartbeat interval, and thus to predict it. We show explicitly that the proposed method, which exploits long-term memory, is superior to the conventional precursory pattern recognition technique, which focuses solely on short-term memory. We believe that our results can be straightforwardly extended to obtain more reliable predictions in other physiological signals like blood pressure, as well as in other complex records exhibiting multifractal behaviour, e.g. turbulent flow, precipitation, river flows and network traffic.

  1. Conversion of Low-Flow Priapism to High-Flow State Using T-Shunt with Tunneling.

    Science.gov (United States)

    Mistry, Neil A; Tadros, Nicholas N; Hedges, Jason C

    2017-01-01

    Introduction . The three types of priapism are stuttering, arterial (high-flow, nonischemic), and venoocclusive (low-flow, ischemic). These are usually distinct entities and rarely occur in the same patient. T-shunts and other distal shunts are frequently combined with tunneling, but a seldom recognized potential complication is conversion to a high-flow state. Case Presentation . We describe 2 cases of men who presented with low-flow priapism episodes that were treated using T-shunts with tunneling that resulted with both men having recurrent erections shortly after surgery that were found to be consistent with high-flow states. Case 1 was a 33-year-old male with sickle cell anemia and case 2 was a 24-year-old male with idiopathic thrombocytopenic purpura. In both cases the men were observed over several weeks and both men returned to normal erectile function. Conclusions . Historically, proximal shunts were performed only in cases when distal shunts failed and carry a higher risk of serious complications. T-shunts and other distal shunts combined with tunneling are being used more frequently in place of proximal shunts. These cases illustrate how postoperative erections after T-shunts with tunneling can signify a conversion from low-flow to high-flow states and could potentially be misdiagnosed as an operative failure.

  2. Hideout and hideout return of tri-sodium phosphate in PWR steam generators

    Energy Technology Data Exchange (ETDEWEB)

    Feron, D.; You, D. [CEA/DEN - Laboratoire d' Etude de la Corrosion Aqueuse, Saclay (France); Turluer, G. [CEA/IPSN-Service d' Analyse des Materiels et des Structures, Fontenay-aux-Roses (France)

    2002-07-01

    Tri-sodium phosphate is used as a chemical conditioner of several sub-systems in secondary circuits of PWR. As confirmed by the international experience feedback of the secondary water chemistry, it can appear as a pollutant of the secondary water circuits, whereby it can concentrate in some areas of restricted flow or deposits in the steam generators. The issues raised by those occurrences prompted the safety French authorities (IPSN) to develop a model boiler investigation programme to assess the respective sodium/phosphate behaviour as a result of hideout and hideout return processes. Hideout and hideout return experiments have been performed with three model boilers in order to investigate the behaviour of tri-sodium phosphate pollution with three different configurations: only tube-tube support plate crevices, only sludge at the bottom of the tubes, or with only ''free'' tube surfaces. Obtained results, with discontinuous pollutions at some mg.kg{sup -1}, can be summarised as follow: low hideout on the free surface of the tubes (less than 10%), hideout is more important when tube-tube support plate crevices are present (10 to 30%), maximum hideout is obtained when there is some sludge at the bottom of the tubes (30 to 90%), Hideout return data are always very low compared to the hideout quantities, due to the formation of solid compound with alumina and silica. (authors)

  3. Hideout and hideout return of tri-sodium phosphate in PWR steam generators

    International Nuclear Information System (INIS)

    Feron, D.; You, D.; Turluer, G.

    2002-01-01

    Tri-sodium phosphate is used as a chemical conditioner of several sub-systems in secondary circuits of PWR. As confirmed by the international experience feedback of the secondary water chemistry, it can appear as a pollutant of the secondary water circuits, whereby it can concentrate in some areas of restricted flow or deposits in the steam generators. The issues raised by those occurrences prompted the safety French authorities (IPSN) to develop a model boiler investigation programme to assess the respective sodium/phosphate behaviour as a result of hideout and hideout return processes. Hideout and hideout return experiments have been performed with three model boilers in order to investigate the behaviour of tri-sodium phosphate pollution with three different configurations: only tube-tube support plate crevices, only sludge at the bottom of the tubes, or with only ''free'' tube surfaces. Obtained results, with discontinuous pollutions at some mg.kg -1 , can be summarised as follow: low hideout on the free surface of the tubes (less than 10%), hideout is more important when tube-tube support plate crevices are present (10 to 30%), maximum hideout is obtained when there is some sludge at the bottom of the tubes (30 to 90%), Hideout return data are always very low compared to the hideout quantities, due to the formation of solid compound with alumina and silica. (authors)

  4. Does Aggregated Returns Disclosure Increase Portfolio Risk Taking?

    Science.gov (United States)

    Beshears, John; Choi, James J.; Laibson, David; Madrian, Brigitte C.

    2016-01-01

    Many experiments have found that participants take more investment risk if they see returns less frequently, see portfolio-level returns (rather than each individual asset’s returns), or see long-horizon (rather than one-year) historical return distributions. In contrast, we find that such information aggregation treatments do not affect total equity investment when we make the investment environment more realistic than in prior experiments. Previously documented aggregation effects are not robust to changes in the risky asset’s return distribution or the introduction of a multi-day delay between portfolio choice and return realizations. PMID:28553012

  5. How Robust Are the Surface Temperature Fingerprints of the Atlantic Overturning Meridional Circulation on Monthly Time Scales?

    Science.gov (United States)

    Alexander-Turner, R.; Ortega, P.; Robson, J. I.

    2018-04-01

    It has been suggested that changes in the Atlantic Meridional Overturning Circulation (AMOC) can drive sea surface temperature (SST) on monthly time scales (Duchez et al., 2016, https://doi.org/10.1002/2017GB005667). However, with only 11 years of continuous observations, the validity of this result over longer, or different, time periods is uncertain. In this study, we use a 120 yearlong control simulation from a high-resolution climate model to test the robustness of the AMOC fingerprints. The model reproduces the observed AMOC seasonal cycle and its variability, and the observed 5-month lagged AMOC-SST fingerprints derived from 11 years of data. However, the AMOC-SST fingerprints are very sensitive to the particular time period considered. In particular, both the Florida current and the upper mid-ocean transport produce highly inconsistent fingerprints when using time periods shorter than 30 years. Therefore, several decades of RAPID observations will be necessary to determine the real impact of the AMOC on SSTs at monthly time scales.

  6. Cloud motions on Venus - Global structure and organization

    Science.gov (United States)

    Limaye, S. S.; Suomi, V. E.

    1981-01-01

    Results on cloud motions on Venus obtained over a period of 3.5 days from Mariner 10 television images are presented. The implied atmosphere flow is almost zonal everywhere on the visible disk, and is in the same retrograde sense as the solid planet. Objective analysis of motions suggests the presence of jet cores (-130 m/s) and organized atmospheric waves. The longitudinal mean meridional profile of the zonal component of motion of the ultraviolet features shows presence of a midlatitude jet stream (-110 m/s). The mean zonal component is -97 m/s at the equator. The mean meridional motion at most latitudes is directed toward the pole in either hemisphere and is at least an order of magnitude smaller so that the flow is nearly zonal. A tentative conclusion from the limited coverage available from Mariner 10 is that at the level of ultraviolet features mean meridional circulation is the dominant mode of poleward angular momentum transfer as opposed to the eddy circulation.

  7. Malaria burden in irregular migrants returning to Sri Lanka from human smuggling operations in West Africa and implications for a country reaching malaria elimination.

    Science.gov (United States)

    Wickramage, K; Galappaththy, G N L

    2013-05-01

    The number of malaria cases among irregular migrants returning to Sri Lanka has not been investigated. In the first 6 months of 2012 we screened 287 irregular migrants returning from seven West African nations to Sri Lanka for malaria to ascertain the risk of infection during migration. Four men were diagnosed as having malaria: three with Plasmodium falciparum had travelled to Togo and one with P. vivax had travelled to Guinea. The risk of contracting malaria was 14 cases per 1000. Facilitating a safe return with selective screening for at-risk inbound migrants flows is desirable as Sri Lanka advances towards its goal of malaria elimination.

  8. Three-dimensional inviscid analysis of radial-turbine flow and a limited comparison with experimental data

    Science.gov (United States)

    Choo, Y. K.; Civinskas, K. C.

    1985-01-01

    The three-dimensional inviscid DENTON code is used to analyze flow through a radial-inflow turbine rotor. Experimental data from the rotor are compared with analytical results obtained by using the code. The experimental data available for comparison are the radial distributions of circumferentially averaged values of absolute flow angle and total pressure downstream of the rotor exit. The computed rotor-exit flow angles are generally underturned relative to the experimental values, which reflect the boundary-layer separation at the trailing edge and the development of wakes downstream of the rotor. The experimental rotor is designed for a higher-than-optimum work factor of 1.126 resulting in a nonoptimum positive incidence and causing a region of rapid flow adjustment and large velocity gradients. For this experimental rotor, the computed radial distribution of rotor-exit to turbine-inlet total pressure ratios are underpredicted due to the errors in the finite-difference approximations in the regions of rapid flow adjustment, and due to using the relatively coarser grids in the middle of the blade region where the flow passage is highly three-dimensional. Additional results obtained from the three-dimensional inviscid computation are also presented, but without comparison due to the lack of experimental data. These include quasi-secondary velocity vectors on cross-channel surfaces, velocity components on the meridional and blade-to-blade surfaces, and blade surface loading diagrams. Computed results show the evolution of a passage vortex and large streamline deviations from the computational streamwise grid lines. Experience gained from applying the code to a radial turbine geometry is also discussed.

  9. Three-dimensional inviscid analysis of radial turbine flow and a limited comparison with experimental data

    Science.gov (United States)

    Choo, Y. K.; Civinskas, K. C.

    1985-01-01

    The three-dimensional inviscid DENTON code is used to analyze flow through a radial-inflow turbine rotor. Experimental data from the rotor are compared with analytical results obtained by using the code. The experimental data available for comparison are the radial distributions of circumferentially averaged values of absolute flow angle and total pressure downstream of the rotor exit. The computed rotor-exit flow angles are generally underturned relative to the experimental values, which reflect the boundary-layer separation at the trailing edge and the development of wakes downstream of the rotor. The experimental rotor is designed for a higher-than-optimum work factor of 1.126 resulting in a nonoptimum positive incidence and causing a region of rapid flow adjustment and large velocity gradients. For this experimental rotor, the computed radial distribution of rotor-exit to turbine-inlet total pressure ratios are underpredicted due to the errors in the finite-difference approximations in the regions of rapid flow adjustment, and due to using the relatively coarser grids in the middle of the blade region where the flow passage is highly three-dimensional. Additional results obtained from the three-dimensional inviscid computation are also presented, but without comparison due to the lack of experimental data. These include quasi-secondary velocity vectors on cross-channel surfaces, velocity components on the meridional and blade-to-blade surfaces, and blade surface loading diagrams. Computed results show the evolution of a passage vortex and large streamline deviations from the computational streamwise grid lines. Experience gained from applying the code to a radial turbine geometry is also discussed.

  10. Anelastic Models of Fully-Convective Stars: Differential Rotation, Meridional Circulation and Residual Entropy

    Science.gov (United States)

    Sainsbury-Martinez, Felix; Browning, Matthew; Miesch, Mark; Featherstone, Nicholas A.

    2018-01-01

    Low-Mass stars are typically fully convective, and as such their dynamics may differ significantly from sun-like stars. Here we present a series of 3D anelastic HD and MHD simulations of fully convective stars, designed to investigate how the meridional circulation, the differential rotation, and residual entropy are affected by both varying stellar parameters, such as the luminosity or the rotation rate, and by the presence of a magnetic field. We also investigate, more specifically, a theoretical model in which isorotation contours and residual entropy (σ‧ = σ ‑ σ(r)) are intrinsically linked via the thermal wind equation (as proposed in the Solar context by Balbus in 2009). We have selected our simulation parameters in such as way as to span the transition between Solar-like differential rotation (fast equator + slow poles) and ‘anti-Solar’ differential rotation (slow equator + fast poles), as characterised by the convective Rossby number and △Ω. We illustrate the transition from single-celled to multi-celled MC profiles, and from positive to negative latitudinal entropy gradients. We show that an extrapolation involving both TWB and the σ‧/Ω link provides a reasonable estimate for the interior profile of our fully convective stars. Finally, we also present a selection of MHD simulations which exhibit an almost unsuppressed differential rotation profile, with energy balances remaining dominated by kinetic components.

  11. Are there Diminishing Returns to R&D?

    DEFF Research Database (Denmark)

    Madsen, Jakob B.

    Semi-endogenous models and, to some extent, also Schumpeterian models are based on the assumption of diminishing returns to R&D. This paper shows that the null hypothesis of constant returns to R&D cannot be rejected for the OECD countries......Semi-endogenous models and, to some extent, also Schumpeterian models are based on the assumption of diminishing returns to R&D. This paper shows that the null hypothesis of constant returns to R&D cannot be rejected for the OECD countries...

  12. APOLLO 15 HEAT FLOW THERMAL CONDUCTIVITY RDR SUBSAMPLED V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set comprises a reduced, subsampled set of the data returned from the Apollo 15 Heat Flow Experiment from 31 July 1971 through 31 December 1974. The...

  13. APOLLO 17 HEAT FLOW THERMAL CONDUCTIVITY RDR SUBSAMPLED V1.0

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set comprises a reduced, subsampled set of the data returned from the Apollo 17 Heat Flow Experiment from 12 December 1972 through 31 December 1974. The...

  14. Regime switches in the risk-return trade-off

    OpenAIRE

    Marcellino, Massimiliano; Ghysels, Eric; Guerin, Pierre

    2014-01-01

    This paper deals with the estimation of the risk-return trade-off. We use a MIDAS model for the conditional variance and allow for possible switches in the risk-return relation through a Markov-switching specification. We find strong evidence for regime changes in the risk-return relation. This finding is robust to a large range of specifications. In the first regime characterized by low ex-post returns and high volatility, the risk-return relation is reversed, whereas the intuitive positive ...

  15. ANALYSING TURKISH INDIVIDUAL PENSION SYSTEM FEES AND RETURNS

    OpenAIRE

    Peker, Ibrahim

    2018-01-01

    This study aims at categorizing, computing and analyzing fees and costs in Turkish Individual Pension System. To this end, net real returns after all costs were computed and these returns were compared with the disclosed fees and returns. Generally in practice, only fund management fees are taken into consideration for calculating net returns and with this method net annual average (geometric) return of the system is calculated as 2.01% for the 2008-2014 period. However, the results of this s...

  16. Phobos Sample Return: Next Approach

    Science.gov (United States)

    Zelenyi, Lev; Martynov, Maxim; Zakharov, Alexander; Korablev, Oleg; Ivanov, Alexey; Karabadzak, George

    The Martian moons still remain a mystery after numerous studies by Mars orbiting spacecraft. Their study cover three major topics related to (1) Solar system in general (formation and evolution, origin of planetary satellites, origin and evolution of life); (2) small bodies (captured asteroid, or remnants of Mars formation, or reaccreted Mars ejecta); (3) Mars (formation and evolution of Mars; Mars ejecta at the satellites). As reviewed by Galimov [2010] most of the above questions require the sample return from the Martian moon, while some (e.g. the characterization of the organic matter) could be also answered by in situ experiments. There is the possibility to obtain the sample of Mars material by sampling Phobos: following to Chappaz et al. [2012] a 200-g sample could contain 10-7 g of Mars surface material launched during the past 1 mln years, or 5*10-5 g of Mars material launched during the past 10 mln years, or 5*1010 individual particles from Mars, quantities suitable for accurate laboratory analyses. The studies of Phobos have been of high priority in the Russian program on planetary research for many years. Phobos-88 mission consisted of two spacecraft (Phobos-1, Phobos-2) and aimed the approach to Phobos at 50 m and remote studies, and also the release of small landers (long-living stations DAS). This mission implemented the program incompletely. It was returned information about the Martian environment and atmosphere. The next profect Phobos Sample Return (Phobos-Grunt) initially planned in early 2000 has been delayed several times owing to budget difficulties; the spacecraft failed to leave NEO in 2011. The recovery of the science goals of this mission and the delivery of the samples of Phobos to Earth remain of highest priority for Russian scientific community. The next Phobos SR mission named Boomerang was postponed following the ExoMars cooperation, but is considered the next in the line of planetary exploration, suitable for launch around 2022. A

  17. The numerical study of the rake angle of impeller blade in centrifugal compressor

    Science.gov (United States)

    Drozdov, A.; Galerkin, Y.

    2017-08-01

    Investigated impellers have blade surfaces formed by straight generatrix. Blade profiles on shroud and disc surfaces are optimized by velocity diagram control (inviscid, quasi-three dimensional calculations). The blade profiles at hub and shroud blade-to-blade surfaces must be coordinated. A designer can choose the generatrix position at a trailing edge for it. The position is defined by the rake angle that is the angle between a trailing edge generatrix and a meridional plane. Two stages with 3D impellers, vaneless diffusers and return channels were investigated. Seven candidates of impellers of these stages with rake angles in range plus-minus 30 degrees were designed and investigated by quasi-three-dimensional inviscid calculation. CFD-calculations were made for the stages with these impellers. The optimal rake angle is minus 20 degrees for the high flow rate impeller due to lesser blade surface area and favorable meridian velocity field. Zero rake angle is optimal for the medium flow rate impeller where blade surface area is not so important. The combination of inviscid and viscid calculations is the informative instrument for further studies.

  18. Do expectancies of return to work and Job satisfaction predict actual return to work in workers with long lasting LBP?

    Science.gov (United States)

    Opsahl, Jon; Eriksen, Hege R; Tveito, Torill H

    2016-11-17

    Musculoskeletal disorders including low back pain have major individual and socioeconomic consequences as it often leads to disability and long-term sick leave and exclusion from working life. Predictors of disability and return to work often differ, and the dominant knowledge is on predictors for prolonged sick leave and disability. Therefore it is also important to identify key predictors for return to work. The aim of the study was to assess if overall job satisfaction and expectancies of return to work predicts actual return to work after 12 months, among employees with long lasting low back pain, and to assess if there were gender differences in the predictors. Data from the Cognitive interventions and nutritional supplements trial (CINS Trial) was used. Predictors for return to work were examined in 574 employees that had been on sick leave 2-10 months for low back pain, before entering the trial. Data were analysed with multiple logistic regression models stratified by gender, and adjusted for potential confounders. Regardless of gender high expectancies were a strong and significant predictor of return to work at 12 months, while high levels of job satisfaction were not a significant predictor. There were no differences in the levels of expectancies or overall job satisfaction between men and women. However, men had in general higher odds of returning to work compared with women. Among individuals with long lasting low back pain high expectancies of returning to work were strongly associated with successful return to work. We do not know what factors influence individual expectancies of return to work. Screening expectancies and giving individuals with low expectancies interventions with a goal to change expectancies of return to work, such as CBT or self-management interventions, may contribute to increase actual return to work. http://www.clinicaltrials.gov/ , with registration number NCT00463970 . The trial was registered at the 18th of April 2007.

  19. Optimizing meridional advection of the Advanced Research WRF (ARW) dynamics for Intel Xeon Phi coprocessor

    Science.gov (United States)

    Mielikainen, Jarno; Huang, Bormin; Huang, Allen H.-L.

    2015-05-01

    The most widely used community weather forecast and research model in the world is the Weather Research and Forecast (WRF) model. Two distinct varieties of WRF exist. The one we are interested is the Advanced Research WRF (ARW) is an experimental, advanced research version featuring very high resolution. The WRF Nonhydrostatic Mesoscale Model (WRF-NMM) has been designed for forecasting operations. WRF consists of dynamics code and several physics modules. The WRF-ARW core is based on an Eulerian solver for the fully compressible nonhydrostatic equations. In the paper, we optimize a meridional (north-south direction) advection subroutine for Intel Xeon Phi coprocessor. Advection is of the most time consuming routines in the ARW dynamics core. It advances the explicit perturbation horizontal momentum equations by adding in the large-timestep tendency along with the small timestep pressure gradient tendency. We will describe the challenges we met during the development of a high-speed dynamics code subroutine for MIC architecture. Furthermore, lessons learned from the code optimization process will be discussed. The results show that the optimizations improved performance of the original code on Xeon Phi 7120P by a factor of 1.2x.

  20. KINERJA KEUANGAN KONVENSIONAL, ECONOMIC VALUE ADDED, DAN RETURN SAHAM

    Directory of Open Access Journals (Sweden)

    Bambang Sudiyatno

    2011-09-01

    Full Text Available Penelitian ini bertujuan untuk menguji pengaruh kinerja keuangan konvensional; Return on Asset (ROA, Return on Equity (ROE, Residual Income (RI, dan kinerja keuangan yang lebih modern; Economic Value Added (EVA terhadap return saham pada perusahaan-perusahaan dalam industry makanan dan minuman yang terdaftar di Bursa Efek Indonesia. Pengambilan sampel dalam penelitian ini menggunakan metode sensus, karena semua perusahaan dalam industry makanan dan minuman digunakan sebagai sampel. Namun dalam proses samplingnya mengunakan metode purposive sampling, yaitu menggunakan sampel dengan criteria-kriteria tertentu. Hasil penelitian menunjukkan bahwa Return on Asset (ROA dan Residual Income (RI berpengaruh positif dan secara statistik signifikan terhadap return saham pada level signifikansi 1%. Sedangkan Return on Equity (ROE berpengaruh negative dan secara statistik signifikan terhadap return saham pada level signifikansi 10%, dan Economic Value Added (ERA berpengaruh positif tetapi tidak signifikan terhadap return saham.This study aims to test the effect of conventional financial performance i.e. Return on Asset (ROA, Return on Equity (ROE, Residual Income (RI, and the more modern financial performance which is Economic Value Added (EVA toward stock returns on companies in the food and beverage industry listed in Indonesia Stock Exchange. Sampling technique in this study uses the census method, all companies in the food and beverage industry are used as a sample. The process of sampling using purposive sampling method. The result shows that Return On Asset (ROA and Residual Income (RI are positive and statistic significant impact on the stock returns at significance level 1%. While the Return on Equity (ROE is negative and statistic significant impact on the stock returns at significance level 10%, Economic Value Added (EVA is positive and statistic not significant impact on the stock returns.

  1. The Determinants of Return Migration: Evidence for Kosovo

    Directory of Open Access Journals (Sweden)

    Ardiana Gashi

    2015-12-01

    Full Text Available Return migration represents a potentially important contributor to economic development for countries that are large exporters of labor. This paper provides an analysis of the determinants of return migration to Kosovo, a country with an especially high level of recent emigration. The findings of this investigation suggest that there is a non-linear relationship between the age of the migrant and their probability of returning. In addition, the more educated migrants and those that have acquired additional education whilst abroad are more likely to return, whereas recent migrants, those that possess permanent resident status and have their family abroad are less likely to return. As expected, the stronger the family ties of a migrant with their home country, the more likely they are to return. Finally, migrants that are expected to invest in businesses in Kosovo are more inclined to return. Together these findings suggest that return migration may be an important contributor to economic development in Kosovo and policies are outlined that could strengthen this contribution.

  2. Return Migration among Elderly, Chronically Ill Bosnian Refugees

    DEFF Research Database (Denmark)

    Handlos, Line Neerup; Olwig, Karen Fog; Bygbjerg, Ib Christian

    2015-01-01

    Elderly migrants constitute a considerable share of global return migration; nevertheless, literature on the health aspects of the return migration among these migrants is still scarce. This study explores the significance of return migration among elderly, chronically ill Bosnian refugees from D...... of illness, health did matter. Viewed as physical, social and mental well-being in line with WHO's definition of health, health was indeed one of the most important factors when the decision to return was made....... that physical health, in the sense of the absence of illness and easy access to necessary health-care services and medicines, was not highly prioritized when the decision was made whether or not to return. However, if health is regarded more broadly as involving more than mere physical health and the absence......Elderly migrants constitute a considerable share of global return migration; nevertheless, literature on the health aspects of the return migration among these migrants is still scarce. This study explores the significance of return migration among elderly, chronically ill Bosnian refugees from...

  3. Corporate Governance and Equity Returns

    OpenAIRE

    Uchida, Shigeru

    2012-01-01

    This paper analyses the relationship between corporate governance and equity returns from the small investors view point. A primary survey has been conducted to gather the data required to examine the link. Preliminary result of the study shows that the four elements of governance: board structure, transparency, fairness and responsibility are positively related with equity returns.

  4. 22 CFR 42.22 - Returning resident aliens.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Returning resident aliens. 42.22 Section 42.22... Returning resident aliens. (a) Requirements for returning resident status. An alien shall be classifiable as... presented that: (1) The alien had the status of an alien lawfully admitted for permanent residence at the...

  5. A Compound Detection System Based on Ultrasonic Flow Rate and Concentration

    Directory of Open Access Journals (Sweden)

    Qing-Hui WANG

    2014-02-01

    Full Text Available This paper proposes a new detection system for monitoring gas concentration and flow rate. Velocity difference of ultrasonic wave in bi-directional propagation in measured gas is recorded and utilized for computing the online gas concentration and flow rate. Meanwhile, the temperature compensation, return signal processing and error analysis algorithms are applied to improve the accuracy. The experimental results show that, compared with the single sensor measurement of gas flow rate or concentration, the proposed detection system with lower cost and higher accuracy can be applied in the occasion which needs simultaneous monitoring of gas concentration and flow rate.

  6. Volatility return intervals analysis of the Japanese market

    Science.gov (United States)

    Jung, W.-S.; Wang, F. Z.; Havlin, S.; Kaizoji, T.; Moon, H.-T.; Stanley, H. E.

    2008-03-01

    We investigate scaling and memory effects in return intervals between price volatilities above a certain threshold q for the Japanese stock market using daily and intraday data sets. We find that the distribution of return intervals can be approximated by a scaling function that depends only on the ratio between the return interval τ and its mean . We also find memory effects such that a large (or small) return interval follows a large (or small) interval by investigating the conditional distribution and mean return interval. The results are similar to previous studies of other markets and indicate that similar statistical features appear in different financial markets. We also compare our results between the period before and after the big crash at the end of 1989. We find that scaling and memory effects of the return intervals show similar features although the statistical properties of the returns are different.

  7. Brachial blood flow under relative levels of blood flow restriction is decreased in a nonlinear fashion.

    Science.gov (United States)

    Mouser, J Grant; Ade, Carl J; Black, Christopher D; Bemben, Debra A; Bemben, Michael G

    2018-05-01

    Blood flow restriction (BFR), the application of external pressure to occlude venous return and restrict arterial inflow, has been shown to increase muscular size and strength when combined with low-load resistance exercise. BFR in the research setting uses a wide range of pressures, applying a pressure based upon an individual's systolic pressure or a percentage of occlusion pressure; not a directly determined reduction in blood flow. The relationship between relative pressure and blood flow has not been established. To measure blood flow in the arm under relative levels of BFR. Forty-five people (18-40 years old) participated. Arterial occlusion pressure in the right arm was measured using a 5-cm pneumatic cuff. Blood flow in the brachial artery was measured at rest and at pressures between 10% and 90% of occlusion using ultrasound. Blood flow decreased in a nonlinear, stepped fashion. Blood flow decreased at 10% of occlusion and remained constant until decreasing again at 40%, where it remained until 90% of occlusion. The decrease in brachial blood flow is not proportional to the applied relative pressure. The prescription of blood flow restriction should take into account the stimulus provided at each relative level of blood flow. © 2017 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  8. Return currents in solar flares - Collisionless effects

    Science.gov (United States)

    Rowland, H. L.; Vlahos, L.

    1985-01-01

    If the primary, precipitating electrons in a solar flare are unstable to beam plasma interactions, it is shown that strong Langmuir turbulence can seriously modify the way in which a return current is carried by the background plasma. In particular, the return (or reverse) current will not be carried by the bulk of the electrons, but by a small number of high velocity electrons. For beam/plasma densities greater than 0.01, this can reduce the effects of collisions on the return current. For higher density beams where the return current could be unstable to current driven instabilities, the effects of strong turbulence anomalous resistivity is shown to prevent the appearance of such instabilities. Again in this regime, how the return current is carried is determined by the beam generated strong turbulence.

  9. Value at Risk and Hedge Fund Return - Does High Risk Bring High Return?

    OpenAIRE

    Jing, Tao; Zhao, Hongxiang

    2010-01-01

    This paper mainly focuses on the correlation between live hedge fund return and their value at risk (VaR), and is based on the historical data from May 2000 to April 2010. The authors adopt portfolio level analyses and fund level cross-sectional regression, and find that there is significant positive correlation, both statistically and economically, between the hedge fund return and VaRs (parametric, non-parametric and GARCH). Further research is conducted by sub-dividing the overall period i...

  10. Analysis of energy flow during playground surface impacts.

    Science.gov (United States)

    Davidson, Peter L; Wilson, Suzanne J; Chalmers, David J; Wilson, Barry D; Eager, David; McIntosh, Andrew S

    2013-10-01

    The amount of energy dissipated away from or returned to a child falling onto a surface will influence fracture risk but is not considered in current standards for playground impact-attenuating surfaces. A two-mass rheological computer simulation was used to model energy flow within the wrist and surface during hand impact with playground surfaces, and the potential of this approach to provide insights into such impacts and predict injury risk examined. Acceleration data collected on-site from typical playground surfaces and previously obtained data from children performing an exercise involving freefalling with a fully extended arm provided input. The model identified differences in energy flow properties between playground surfaces and two potentially harmful surface characteristics: more energy was absorbed by (work done on) the wrist during both impact and rebound on rubber surfaces than on bark, and rubber surfaces started to rebound (return energy to the wrist) while the upper limb was still moving downward. Energy flow analysis thus provides information on playground surface characteristics and the impact process, and has the potential to identify fracture risks, inform the development of safer impact-attenuating surfaces, and contribute to development of new energy-based arm fracture injury criteria and tests for use in conjunction with current methods.

  11. The onset of modern-like Atlantic meridional overturning circulation at the Eocene-Oligocene transition: Evidence, causes, and possible implications for global cooling

    Science.gov (United States)

    Abelson, Meir; Erez, Jonathan

    2017-06-01

    A compilation of benthic δ18O from the whole Atlantic and the Southern Ocean (Atlantic sector) shows two major jumps in the interbasinal gradient of δ18O (Δδ18O) during the Eocene and the Oligocene: one at ˜40 Ma and the second concomitant with the isotopic event of the Eocene-Oligocene transition (EOT), ˜33.7 Ma ago. From previously published circulation models and proxies, we show that the first Δδ18O jump reflects the thermal isolation of Antarctica associated with the proto-Antarctic circumpolar current (ACC). The second marks the onset of interhemispheric northern-sourced circulation cell, similar to the modern Atlantic meridional overturning circulation (AMOC). The onset of AMOC-like circulation slightly preceded (100-300 kyr) the EOT, as we show by the high-resolution profiles of δ18O and δ13C previously published from DSDP/ODP sites in the Southern Ocean and South Atlantic. These events coincide with the onset of antiestuarine circulation between the Nordic seas and the North Atlantic which started around the EOT and may be connected to the deepening of the Greenland-Scotland Ridge. We suggest that while the shallow proto-ACC supplied the energy for deep ocean convection in the Southern Hemisphere, the onset of the interhemispheric northern circulation cell was due to the significant EOT intensification of deepwater formation in the North Atlantic driven by the Nordic antiestuarine circulation. This onset of the interhemispheric northern-sourced circulation cell could have prompted the EOT global cooling.Plain Language SummaryThe Eocene-Oligocene transition is the major abrupt climatic event during the Cenozoic, which marks the major step to the icehouse world. We show that this transition is a shift to a world with Atlantic meridional overturning circulation (AMOC) and slightly preceded this transition. Thus, possibly was a major factor in this climatic shift.

  12. Mars Earth Return Vehicle (MERV) Propulsion Options

    Science.gov (United States)

    Oleson, Steven R.; McGuire, Melissa L.; Burke, Laura; Fincannon, James; Warner, Joe; Williams, Glenn; Parkey, Thomas; Colozza, Tony; Fittje, Jim; Martini, Mike; hide

    2010-01-01

    The COMPASS Team was tasked with the design of a Mars Sample Return Vehicle. The current Mars sample return mission is a joint National Aeronautics and Space Administration (NASA) and European Space Agency (ESA) mission, with ESA contributing the launch vehicle for the Mars Sample Return Vehicle. The COMPASS Team ran a series of design trades for this Mars sample return vehicle. Four design options were investigated: Chemical Return /solar electric propulsion (SEP) stage outbound, all-SEP, all chemical and chemical with aerobraking. The all-SEP and Chemical with aerobraking were deemed the best choices for comparison. SEP can eliminate both the Earth flyby and the aerobraking maneuver (both considered high risk by the Mars Sample Return Project) required by the chemical propulsion option but also require long low thrust spiral times. However this is offset somewhat by the chemical/aerobrake missions use of an Earth flyby and aerobraking which also take many months. Cost and risk analyses are used to further differentiate the all-SEP and Chemical/Aerobrake options.

  13. Linkage between company scores and stock returns

    Directory of Open Access Journals (Sweden)

    Saban Celik

    2017-12-01

    Full Text Available Previous studies on company scores conducted at firm-level, generally concluded that there exists a positive relation between company scores and stock returns. Motivated by these studies, this study examines the relationship between company scores (Corporate Governance Score, Economic Score, Environmental Score, and Social Score and stock returns, both at portfolio-level analysis and firm-level cross-sectional regressions. In portfolio-level analysis, stocks are sorted based on each company scores and quintile portfolio are formed with different levels of company scores. Then, existence and significance of raw returns and risk-adjusted returns difference between portfolios with the extreme company scores (portfolio 10 and portfolio 1 is tested. In addition, firm-level cross-sectional regression is performed to examine the significance of company scores effects with control variables. While portfolio-level analysis results indicate that there is no significant relation between company scores and stock returns; firm-level analysis indicates that economic, environmental, and social scores have effect on stock returns, however, significance and direction of these effects change, depending on the included control variables in the cross-sectional regression.

  14. Atlantic Meridional Overturning Circulation response to idealized external forcing

    Energy Technology Data Exchange (ETDEWEB)

    Park, W.; Latif, M. [Leibniz-Institut fuer Meereswissenschaften an der Universitaet Kiel, Kiel (Germany)

    2012-10-15

    The response of the Atlantic Meridional Overturning Circulation (AMOC) to idealized external (solar) forcing is studied in terms of the internal (unforced) AMOC modes with the Kiel Climate Model (KCM), a coupled atmosphere-ocean-sea ice general circulation model. The statistical investigation of KCM's internal AMOC variability obtained from a multi-millennial control run yields three distinct modes: a multi-decadal mode with a period of about 60 years, a quasi-centennial mode with a period of about 100 years and a multi-centennial mode with a period of about 300-400 years. Most variance is explained by the multi-centennial mode, and the least by the quasi-centennial mode. The solar constant varies sinusoidally with two different periods (100 and 60 years) in forced runs with KCM. The AMOC response to the external forcing is rather complex and nonlinear. It involves strong changes in the frequency structure of the variability. While the control run depicts multi-timescale behavior, the AMOC variability in the experiment with 100 year forcing period is channeled into a relatively narrow band centered near the forcing period. It is the quasi-centennial AMOC mode with a period of just under 100 years which is excited, although it is heavily damped in the control run. Thus, the quasi-centennial mode retains its period which does not correspond exactly to the forcing period. Surprisingly, the quasi-centennial mode is also most strongly excited when the forcing period is set to 60 years, the period of the multi-decadal mode which is rather prominent in the control run. It is largely the spatial structure of the forcing rather than its period that determines which of the three internal AMOC modes is excited. The results suggest that we need to understand the full modal structure of the internal AMOC variability in order to understand the circulation's response to external forcing. This could be a challenge for climate models: we cannot necessarily expect that the

  15. Inactive nurses in Taiwan: human capital, intention to return to hospital nursing, and incentives for returning.

    Science.gov (United States)

    Yu, Hsing-Yi; Tang, Fu-In; Chen, I-Ju; Yin, Teresa J C; Chen, Chu-Chieh; Yu, Shu

    2016-04-01

    To investigate inactive nurses' human capital, intention to return to hospital nursing and incentives for returning. Few studies have discussed the loss of human capital with regard to inactive nurses and how to attract them to return to clinical work. Systematic random sampling was used, with 328 subjects completing the mailed questionnaires, resulting in a response rate of 25.4%. Inactive nurses not only had moderate to high human capital (average years of nursing experience was 10.29, with moderate to high levels of nursing professional commitment and nursing competence) and were young. Forty-three percent of subjects reported intending to return to hospital nursing. Sufficient nurse staffing, greater safety in the working environment, and re-entry preparation programmes were incentives for returning. Recruiting inactive nurses back to hospital work is vital and feasible as inactive nurses had a moderate to high degree of human capital. The most feasible way is offering reasonable working conditions, in particular, providing sufficient staffing, a safe working environment and re-entry preparation programmes. The findings confirm the human capital of inactive nurses and provide concrete directions for nursing managers to follow when recruiting inactive nurses to hospital nursing. © 2015 John Wiley & Sons Ltd.

  16. A commentary on the Atlantic meridional overturning circulation stability in climate models

    Science.gov (United States)

    Gent, Peter R.

    2018-02-01

    The stability of the Atlantic meridional overturning circulation (AMOC) in ocean models depends quite strongly on the model formulation, especially the vertical mixing, and whether it is coupled to an atmosphere model. A hysteresis loop in AMOC strength with respect to freshwater forcing has been found in several intermediate complexity climate models and in one fully coupled climate model that has very coarse resolution. Over 40% of modern climate models are in a bistable AMOC state according to the very frequently used simple stability criterion which is based solely on the sign of the AMOC freshwater transport across 33° S. In a recent freshwater hosing experiment in a climate model with an eddy-permitting ocean component, the change in the gyre freshwater transport across 33° S is larger than the AMOC freshwater transport change. This casts very strong doubt on the usefulness of this simple AMOC stability criterion. If a climate model uses large surface flux adjustments, then these adjustments can interfere with the atmosphere-ocean feedbacks, and strongly change the AMOC stability properties. AMOC can be shut off for many hundreds of years in modern fully coupled climate models if the hosing or carbon dioxide forcing is strong enough. However, in one climate model the AMOC recovers after between 1000 and 1400 years. Recent 1% increasing carbon dioxide runs and RCP8.5 future scenario runs have shown that the AMOC reduction is smaller using an eddy-resolving ocean component than in the comparable standard 1° ocean climate models.

  17. Uso do produto MOD13Q1 do sensor Modis para análise temporal e mapeamento das florestas nas Serras do Sudeste e Campanha Meridional do Rio Grande do Sul

    Directory of Open Access Journals (Sweden)

    Ana Caroline Paim Benedetti

    2013-06-01

    Full Text Available Imagens NDVI (Índice de Vegetação por Diferença Normalizada do sensor Modis foram utilizadas para mapear as classes de uso e cobertura da terra nas Serras do Sudeste e Campanha Meridional do Rio Grande do Sul. A metodologia compreendeu a elaboração de um banco de dados espaciais e a aplicação de técnicas de processamento digital (contraste linear, classificação digital e operações aritméticas sobre imagens dos satélites Landsat e Terra de diversas datas. Os resultados indicaram que a cobertura florestal passou de 8,6% para 11,6% e 14,3% da área total da microrregião Serras do Sudeste, entre os anos 2000, 2004 e 2008. Na Campanha Meridional, a expansão da cobertura florestal passou de 11,1% para 11,2% e 11,5% da área total no mesmo período. Conclui-se que imagens MOD13Q1, de baixa resolução espacial (250 m, podem ser usadas em grandes áreas para mapear florestas e os demais temas adequadamente.

  18. Exploring Longitudinal Risk-return Relationships

    DEFF Research Database (Denmark)

    Andersen, Torben J.; Bettis, Richard A.

    2015-01-01

    We study a longitudinal fit model of adaptation and its association with the longitudinal risk-return relationship. The model allows the firm to adjust its position in response to partial learning about a changing environment characterized by two path-dependent processes—a random walk and a stoch......We study a longitudinal fit model of adaptation and its association with the longitudinal risk-return relationship. The model allows the firm to adjust its position in response to partial learning about a changing environment characterized by two path-dependent processes—a random walk...... can lead to the inverse longitudinal risk-return relationships observed empirically. We discuss this apparent paradox and the possible resolution between mindless and conscious behavior as plausible causes of the longitudinal Bowman Paradox....

  19. Mapping return currents in laser-generated Z-pinch plasmas using proton deflectometry

    International Nuclear Information System (INIS)

    Manuel, M. J.-E.; Sinenian, N.; Seguin, F. H.; Li, C. K.; Frenje, J. A.; Rinderknecht, H. G.; Casey, D. T.; Zylstra, A. B.; Petrasso, R. D.; Beg, F. N.

    2012-01-01

    Dynamic return currents and electromagnetic field structure in laser-generated Z-pinch plasmas have been measured using proton deflectometry. Experiments were modeled to accurately interpret deflections observed in proton radiographs. Current flow is shown to begin on axis and migrate outwards with the expanding coronal plasma. Magnetic field strengths of ∼1 T are generated by currents that increase from ∼2 kA to ∼7 kA over the course of the laser pulse. Proton deflectometry has been demonstrated to be a practical alternative to other magnetic field diagnostics for these types of plasmas.

  20. The Reference Return Ratio

    DEFF Research Database (Denmark)

    Nicolaisen, Jeppe; Faber Frandsen, Tove

    2008-01-01

    The paper introduces a new journal impact measure called The Reference Return Ratio (3R). Unlike the traditional Journal Impact Factor (JIF), which is based on calculations of publications and citations, the new measure is based on calculations of bibliographic investments (references) and returns...... (citations). A comparative study of the two measures shows a strong relationship between the 3R and the JIF. Yet, the 3R appears to correct for citation habits, citation dynamics, and composition of document types - problems that typically are raised against the JIF. In addition, contrary to traditional...

  1. Vortex breakdown in a truncated conical bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Balci, Adnan; Brøns, Morten [DTU Compute, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Herrada, Miguel A [E.S.I, Universidad de Sevilla, Camino de los Descubrimientos s/n, E-41092 (Spain); Shtern, Vladimir N, E-mail: mobr@dtu.dk [Shtern Research and Consulting, Houston, TX 77096 (United States)

    2015-12-15

    This numerical study explains the eddy formation and disappearance in a slow steady axisymmetric air–water flow in a vertical truncated conical container, driven by the rotating top disk. Numerous topological metamorphoses occur as the water height, H{sub w}, and the bottom-sidewall angle, α, vary. It is found that the sidewall convergence (divergence) from the top to the bottom stimulates (suppresses) the development of vortex breakdown (VB) in both water and air. At α = 60°, the flow topology changes eighteen times as H{sub w} varies. The changes are due to (a) competing effects of AMF (the air meridional flow) and swirl, which drive meridional motions of opposite directions in water, and (b) feedback of water flow on AMF. For small H{sub w}, the AMF effect dominates. As H{sub w} increases, the swirl effect dominates and causes VB. The water flow feedback produces and modifies air eddies. The results are of fundamental interest and can be relevant for aerial bioreactors. (paper)

  2. Vortex breakdown in a truncated conical bioreactor

    International Nuclear Information System (INIS)

    Balci, Adnan; Brøns, Morten; Herrada, Miguel A; Shtern, Vladimir N

    2015-01-01

    This numerical study explains the eddy formation and disappearance in a slow steady axisymmetric air–water flow in a vertical truncated conical container, driven by the rotating top disk. Numerous topological metamorphoses occur as the water height, H w , and the bottom-sidewall angle, α, vary. It is found that the sidewall convergence (divergence) from the top to the bottom stimulates (suppresses) the development of vortex breakdown (VB) in both water and air. At α = 60°, the flow topology changes eighteen times as H w varies. The changes are due to (a) competing effects of AMF (the air meridional flow) and swirl, which drive meridional motions of opposite directions in water, and (b) feedback of water flow on AMF. For small H w , the AMF effect dominates. As H w increases, the swirl effect dominates and causes VB. The water flow feedback produces and modifies air eddies. The results are of fundamental interest and can be relevant for aerial bioreactors. (paper)

  3. Different forms, reasons and motivations for return migration of persons who voluntarily decide to return to their countries of origin.

    Science.gov (United States)

    Callea, S

    1986-03-01

    Although the 1973 oil crisis did not have the drastic effects on immigration which were originally feared, it did end a period of quasi-liberal immigration policy, establish intense and effective international cooperation on immigration, and arouse great interest in immigration studies and research. This paper analyzes the situations arising as a result of the petroleum shortage and focuses on the conditions relating to the return of emigrants to Southern European countries. This new research draws attention to the following fundamental aspects of the immigration problem: 1) the emigrant's return to his homeland cannot be considered a factor in development; it is a positive element in development only if the right socioeconomic conditions exist in the country of origin. 2) Concern for children's education is one of the most common reasons for return. 3) A large percentage of emigrants are satisfied with their work abroad. 4) An emigrant's return potential is wasted due to the slight use that is made of the resources he offers. 5) Returning workers most often want to set up an independent enterprise. 6) Savings are generally used to buy a house or farm. 7) Vocational level does not increase significantly between emigration and returning, though this increase becomes greater the longer the emigrant stays abroad. 8) The number of returning emigrants is too slight to bring about any change in the country of origin. 9) Incentives and subsidies to encourage return have not had a considerable impact on the decision to return. Callea recommends that officials of the country of origin posted abroad be assigned to counsel returning emigrants on finding employment, attending vocational development courses, obtaining housing, accruing interests and savings, and on the problems and perspectives of sociocultural reintegration.

  4. Theoretical interpretation of the observed interplanetary magnetic field radial variation in the outer solar system

    Science.gov (United States)

    Suess, S. T.; Thomas, B. T.; Nerney, S. F.

    1985-01-01

    Observations of the azimuthal component of the IMF are evaluated through the use of an MHD model which shows the effect of magnetic flux tubes opening in the outer solar system. It is demonstrated that the inferred meridional transport of magnetic flux is consistent with predictions by the MHD model. The computed azimuthal and radial magnetic flux deficits are almost identical to the observations. It is suggested that the simplest interpretation of the observations is that meridional flows are created by a direct body force on the plasma. This is consistent with the analytic model of Nerney and Suess (1975), in which such flux deficits in the IMF arise naturally from the meridional gradient in the spiralling field.

  5. Dynamic Transitions and Baroclinic Instability for 3D Continuously Stratified Boussinesq Flows

    Science.gov (United States)

    Şengül, Taylan; Wang, Shouhong

    2018-02-01

    The main objective of this article is to study the nonlinear stability and dynamic transitions of the basic (zonal) shear flows for the three-dimensional continuously stratified rotating Boussinesq model. The model equations are fundamental equations in geophysical fluid dynamics, and dynamics associated with their basic zonal shear flows play a crucial role in understanding many important geophysical fluid dynamical processes, such as the meridional overturning oceanic circulation and the geophysical baroclinic instability. In this paper, first we derive a threshold for the energy stability of the basic shear flow, and obtain a criterion for local nonlinear stability in terms of the critical horizontal wavenumbers and the system parameters such as the Froude number, the Rossby number, the Prandtl number and the strength of the shear flow. Next, we demonstrate that the system always undergoes a dynamic transition from the basic shear flow to either a spatiotemporal oscillatory pattern or circle of steady states, as the shear strength of the basic flow crosses a critical threshold. Also, we show that the dynamic transition can be either continuous or catastrophic, and is dictated by the sign of a transition number, fully characterizing the nonlinear interactions of different modes. Both the critical shear strength and the transition number are functions of the system parameters. A systematic numerical method is carried out to explore transition in different flow parameter regimes. In particular, our numerical investigations show the existence of a hypersurface which separates the parameter space into regions where the basic shear flow is stable and unstable. Numerical investigations also yield that the selection of horizontal wave indices is determined only by the aspect ratio of the box. We find that the system admits only critical eigenmodes with roll patterns aligned with the x-axis. Furthermore, numerically we encountered continuous transitions to multiple

  6. Large scale debris-flow hazard assessment: a geotechnical approach and GIS modelling

    Directory of Open Access Journals (Sweden)

    G. Delmonaco

    2003-01-01

    Full Text Available A deterministic distributed model has been developed for large-scale debris-flow hazard analysis in the basin of River Vezza (Tuscany Region – Italy. This area (51.6 km 2 was affected by over 250 landslides. These were classified as debris/earth flow mainly involving the metamorphic geological formations outcropping in the area, triggered by the pluviometric event of 19 June 1996. In the last decades landslide hazard and risk analysis have been favoured by the development of GIS techniques permitting the generalisation, synthesis and modelling of stability conditions on a large scale investigation (>1:10 000. In this work, the main results derived by the application of a geotechnical model coupled with a hydrological model for the assessment of debris flows hazard analysis, are reported. This analysis has been developed starting by the following steps: landslide inventory map derived by aerial photo interpretation, direct field survey, generation of a database and digital maps, elaboration of a DTM and derived themes (i.e. slope angle map, definition of a superficial soil thickness map, geotechnical soil characterisation through implementation of a backanalysis on test slopes, laboratory test analysis, inference of the influence of precipitation, for distinct return times, on ponding time and pore pressure generation, implementation of a slope stability model (infinite slope model and generalisation of the safety factor for estimated rainfall events with different return times. Such an approach has allowed the identification of potential source areas of debris flow triggering. This is used to detected precipitation events with estimated return time of 10, 50, 75 and 100 years. The model shows a dramatic decrease of safety conditions for the simulation when is related to a 75 years return time rainfall event. It corresponds to an estimated cumulated daily intensity of 280–330 mm. This value can be considered the hydrological triggering

  7. MANAJEMEN LABA, RETURN SAHAM, DAN KINERJA OPERASI SEBAGAI PEMODERASI

    Directory of Open Access Journals (Sweden)

    Farid Addy Sumantri

    2017-09-01

    Full Text Available The purpose of this study was to determine the indications of the practice of earnings management at the time of the IPO, one year after the IPO, and two years after the IPO. This study also examined the effect of earnings management on stock returns and operating performance in moderating the relationship between earnings management and stock returns. The study sample comprised 33 firms that go public in the year 2007 to 2011 using a purposive sampling method. Earnings management is proxied by discretionary accruals using the Modified Jones Model, which used proxy for the stock return is cummulative abnormal returns (CAR, while for the company's operating performance used proxy for the return on assets (ROA. The results showed that there were indications of earnings management at the time of the IPO, one year after the IPO, and two years after the IPO with a lower profit rate. No effect on earnings management is proxied by stock return cummulative abnormal returns (CAR. Operating performance of the company also can not moderate the relationship between earnings management with stock return.   Keywords: Earning Management, Initial Public Offering, Cummulative Abnormal Return, Return On Asset

  8. Evaluation of the return rate of volunteer blood donors

    Directory of Open Access Journals (Sweden)

    Adriana de Fátima Lourençon

    2011-06-01

    Full Text Available BACKGROUND: To convert first-time blood donors into regular volunteer donors is a challenge to transfusion services. OBJECTIVES: This study aims to estimate the return rate of first time donors of the Ribeirão Preto Blood Center and of other blood centers in its coverage region. METHODS: The histories of 115,553 volunteer donors between 1996 and 2005 were analyzed. Statistical analysis was based on a parametric long-term survival model that allows an estimation of the proportion of donors who never return for further donations. RESULTS: Only 40% of individuals return within one year after the first donation and 53% return within two years. It is estimated that 30% never return to donate. Higher return rates were observed among Black donors. No significant difference was found in non-return rates regarding gender, blood type, Rh blood group and blood collection unit. CONCLUSIONS: The low percentage of first-time donors who return for further blood donation reinforces the need for marketing actions and strategies aimed at increasing the return rates.

  9. Return migration as failure or success? : The determinants of return migration intentions among Moroccan migrants in Europe

    NARCIS (Netherlands)

    de Haas, H.; Fokkema, T.; Fihri, M.F.

    2015-01-01

    Different migration theories generate competing hypotheses with regard to determinants of return migration. While neoclassical migration theory associates migration to the failure to integrate at the destination, the new economics of labour migration sees return migration as the logical stage after

  10. ACL Return to Sport Guidelines and Criteria.

    Science.gov (United States)

    Davies, George J; McCarty, Eric; Provencher, Matthew; Manske, Robert C

    2017-09-01

    Because of the epidemiological incidence of anterior cruciate ligament (ACL) injuries, the high reinjury rates that occur when returning back to sports, the actual number of patients that return to the same premorbid level of competition, the high incidence of osteoarthritis at 5-10-year follow-ups, and the effects on the long-term health of the knee and the quality of life for the patient, individualizing the return to sports after ACL reconstruction (ACL-R) is critical. However, one of the challenging but unsolved dilemmas is what criteria and clinical decision making should be used to return an athlete back to sports following an ACL-R. This article describes an example of a functional testing algorithm (FTA) as one method for clinical decision making based on quantitative and qualitative testing and assessment utilized to make informed decisions to return an athlete to their sports safely and without compromised performance. The methods were a review of the best current evidence to support a FTA. In order to evaluate all the complicated domains of the clinical decision making for individualizing the return to sports after ACL-R, numerous assessments need to be performed including the biopsychosocial concepts, impairment testing, strength and power testing, functional testing, and patient-reported outcomes (PROs). The optimum criteria to use for individualizing the return to sports after ACL-R remain elusive. However, since this decision needs to be made on a regular basis with the safety and performance factors of the patient involved, this FTA provides one method of quantitatively and qualitatively making the decisions. Admittedly, there is no predictive validity of this system, but it does provide practical guidelines to facilitate the clinical decision making process for return to sports. The clinical decision to return an athlete back into competition has significant implications ranging from the safety of the athlete, to performance factors and actual

  11. Global Variance Risk Premium and Forex Return Predictability

    OpenAIRE

    Aloosh, Arash

    2014-01-01

    In a long-run risk model with stochastic volatility and frictionless markets, I express expected forex returns as a function of consumption growth variances and stock variance risk premiums (VRPs)—the difference between the risk-neutral and statistical expectations of market return variation. This provides a motivation for using the forward-looking information available in stock market volatility indices to predict forex returns. Empirically, I find that stock VRPs predict forex returns at a ...

  12. Evolução geologica do pre-cambriano da porção centro-leste da serra do Espigão meridional e metalogenese associada

    OpenAIRE

    Luiz Guilherme Knauer

    1990-01-01

    Resumo: A porção centro-leste da Serra do. Espinhaço Meridional é caracterizada principalmente por terrenos de idade Pré-Cambriana, incluindo seqüências do Arqueano (Complexo de Gouveia, de alto grau metamórfico, e Grupo Pedro Pereira, de baixo grau) e do Proterozóico (todas de baixo grau metamórfico: Grupo Costa Sena, Supergrupo Espinhaço sensu stricto, Seqüência Itapanhoacanga, Seqüência Serra do Sapo, Seqüência Jacem e Seqüência Serro), alem de diques e sills básicos metamorfisados em fáci...

  13. The Returns to Entrepreneurship

    DEFF Research Database (Denmark)

    Van Praag, Mirjam; Raknerud, Arvid

    Empirical studies show low pecuniary returns of switching from wage employment to entrepreneurship. We reconsider the pecuniary gains of this switching by employing a two-stage procedure, where the randomness in the timing of inheritance transfers is used as an exclusion restriction to identify...... causal effects. The model is estimated on data covering the whole Norwegian population of individuals matched to the entire population of firms established in the period 2002-2011. The results indicate that the average returns to entrepreneurship are significantly negative for individuals entering...... entrepreneurship through self-employment and modest, but significantly positive, for incorporated startups....

  14. Communication and collaboration among return-to-work stakeholders.

    Science.gov (United States)

    Russell, Elizabeth; Kosny, Agnieszka

    2018-05-17

    Workers who are injured or become ill on the job are best able to return-to-work when stakeholders involved in their case collaborate and communicate. This study examined health care providers' and case managers' engagement in rehabilitation and return-to-work following workplace injury or illness. In-depth interviews were conducted with 97 health care providers and 34 case managers in four Canadian provinces about their experiences facilitating rehabilitation and return-to-work, and interacting with system stakeholders. A qualitative thematic content analysis demonstrated two key findings. Firstly, stakeholders were challenged to collaborate as a result of: barriers to interdisciplinary and cross-professional communication; philosophical differences about the timing and appropriateness of return-to-work; and confusion among health care providers about the workers' compensation system. Secondly, these challenges adversely affected the co-ordination of patient care, and consequentially, injured workers often became information conduits, and effective and timely treatment and return-to-work was sometimes negatively impacted. Communication challenges between health care providers and case managers may negatively impact patient care and alienate treating health care providers. Discussion about role clarification, the appropriateness of early return-to-work, how paperwork shapes health care providers' role expectations, and strengthened inter-professional communication are considered. Implications for Rehabilitation Administrative and conceptual barriers in workers' compensation systems challenge collaboration and communication between health care providers and case managers. Injured workers may become conduits of incorrect information, resulting in adversarial relationships, overturned health care providers' recommendations, and their disengagement from rehabilitation and return-to-work. Stakeholders should clarify the role of health care providers during

  15. Valuation of index-linked cash flows in a Heath-Jarrow-Morton framework

    OpenAIRE

    Alm, Jonas; Lindskog, Filip

    2015-01-01

    In this paper, we study the valuation of stochastic cash flows that exhibit dependence on interest rates. We focus on insurance liability cash flows linked to an index, such as a consumer price index or wage index, where changes in the index value can be partially understood in terms of changes in the term structure of interest rates. Insurance liability cash flows that are not explicitly linked to an index may still be valued in our framework by interpreting index returns as so-called claims...

  16. 26 CFR 301.6103(j)(1)-1 - Disclosures of return information reflected on returns to officers and employees of the...

    Science.gov (United States)

    2010-04-01

    ... related activities. 301.6103(j)(1)-1 Section 301.6103(j)(1)-1 Internal Revenue INTERNAL REVENUE SERVICE... and Returns Returns and Records § 301.6103(j)(1)-1 Disclosures of return information reflected on... related activities. (a) General rule. Pursuant to the provisions of section 6103(j)(1) of the Internal...

  17. Return on Investment from Biochar Application

    Science.gov (United States)

    Current literature has yet to fully address the cost of biochar application or the return on investment to the grower. The objectives were to identify possible on-farm spreader equipment, spreader capacity, application expenses, and rate of return needed for growers to apply biochar economically. Bi...

  18. Does graded return-to-work improve sick-listed workers' chance of returning to regular working hours?

    Science.gov (United States)

    Høgelund, Jan; Holm, Anders; McIntosh, James

    2010-01-01

    Using Danish register and survey data, we examine the effect of a national graded return-to-work program on the probability of sick-listed workers returning to regular working hours. During program participation, the sick-listed worker works fewer hours and receives the normal hourly wage for the hours worked and sickness benefit for the hours off work. When the worker's health improves, working hours are increased until the sick-listed worker is able to work regular hours. Taking account of unobserved differences between program participants and non-participants, we find that participation in the program significantly increases the probability of returning to regular working hours. Copyright 2009 Elsevier B.V. All rights reserved.

  19. Testicular blood flow in varicocele

    International Nuclear Information System (INIS)

    Iwamoto, Teruaki; Hirokawa, Makoto.

    1986-01-01

    Radioisotopic scrotal angiography was applied for study of testicular blood flow of patients with varicocele. Following iv. bolus injection of 10 ∼ 20 mCi of Tc human serum albumine, Tc RBC or Tc pertechnetate, time activity curve of radioactivity at corresponding bilateral areas of scrotum was simultaneously generated and compared. Eighty-four patients with overt varicocele (grade 2 and 3) at left side only, were selected for the present study and eight healthy young volunteers were studied as a control group. Three patterns of time activity curves were recognized. They are as follows. Type 1, where radioactivity was accumulated quickly in left side and then decreased gradually. Bilateral time activity curves were asymmetrical. Type 2, where time activity curves rose gradually and to a higher level at the left side than at the right side. Type 3, where bilateral time activity curves increased gradually, and symmetrically. All of the control group showed the same pattern as Type 3. Of the 84 patients examined, 34 patients showed Type 1, including 7 with grade 2 and 27 with grade 3. Twenty-four patients showed Type 2. consisting of 12 with grade 2 and 12 with grade 3. Twenty-six patients showed Type 3, consisting of 14 with grade 2 and 12 with grade 3. We presumed the following about testicular blood flow in varicocele: Type 1 pattern shows retrograde blood flow from the renal vein to the internal spermatic vein, Type 2 pattern shows poor venous return through the internal spermatic vein and Type 3 pattern shows good venous return though the presence of dilatated pampiniform plexus. (author)

  20. Nasal mucosal blood flow after intranasal allergen challenge

    International Nuclear Information System (INIS)

    Holmberg, K.; Bake, B.; Pipkorn, U.

    1988-01-01

    The nasal mucosal blood flow in patients with allergic rhinitis was determined at nasal allergen challenges with the 133 Xenon washout method. Determinations were made in 12 subjects before and 15 minutes after challenge with diluent and increasing doses of allergen. The time course was followed in eight subjects by means of repeated measurements during 1 hour after a single allergen dose. Finally, the blood flow was measured after unilateral allergen challenge in the contralateral nasal cavity. A dose-dependent decrease in blood flow was found after nasal challenge with increasing doses of allergens, whereas challenge with diluent alone did not induce any changes. The highest allergen dose, which also induced pronounced nasal symptoms, resulted in a decrease in blood flow of 25% (p less than 0.001). The time-course study demonstrated a maximum decrease in blood flow 10 to 20 minutes after challenge and then a gradual return to baseline. Unilateral allergen challenge resulted in a decrease in blood flow in the contralateral, unchallenged nasal cavity, suggesting that part of the allergen-induced changes in blood flow were reflex mediated

  1. Motivational goals, group identifications, and psychosocial adjustment of returning migrants: The case of Jews returning to Russia.

    Science.gov (United States)

    Tartakovsky, Eugene; Patrakov, Eduard; Nikulina, Marina

    2017-12-01

    The present study investigated the motivational goals, group identifications, and psychosocial adjustment of Jews who returned to Russia after emigrating from the republics of the Former Soviet Union to different countries (n = 151). To gain a deeper understanding of these returning migrants, their traits were compared with those of Jews living in Russia who did not emigrate (n = 935). Compared to locals, returnees reported a higher preference for the openness to change and self-enhancement values and a lower preference for the conservation values; there was no difference in the self-transcendence values. Returning migrants had a relatively weak affiliation with the home country: they had a weaker identification with the home country than with the country of emigration, their identification with Russians was weaker than that among Jews who did not emigrate from Russia, and their intention to emigrate (again) from Russia was greater than that among locals. However, the Jewish identification of returning migrants was similar to that of locals. The adjustment of returning migrants varied across different dimensions: their economic adjustment was better than that of locals; however, the interpersonal adjustment of returnees was less successful than among locals. © 2016 International Union of Psychological Science.

  2. Nonlinear Interaction of Waves in Rotating Spherical Layers

    Science.gov (United States)

    Zhilenko, D.; Krivonosova, O.; Gritsevich, M.

    2018-01-01

    Flows of a viscous incompressible fluid in a spherical layer that are due to rotational oscillations of its inner boundary at two frequencies with respect to the state of rest are numerically studied. It is found that an increase in the amplitude of oscillations of the boundary at the higher frequency can result in a significant enhancement of the low-frequency mode in a flow near the outer boundary. The direction of propagation of the low-frequency wave changes from radial to meridional, whereas the high-frequency wave propagates in the radial direction in a limited inner region of the spherical layer. The role of the meridional circulation in the energy exchange between spaced waves is demonstrated.

  3. Economic and accounting rates of return

    NARCIS (Netherlands)

    Feenstra, D.W.; Wang, H.

    2000-01-01

    The rate of return on invested capital is a central concept in financial analysis. The purpose of calculating the rate of return on investment in general is to measure the financial performance, to assess the desirability of a project and to make decisions on the valuation of firms. Financial

  4. Parasitic diseases in the returning traveller

    African Journals Online (AJOL)

    2009-06-11

    Jun 11, 2009 ... exception is infection with schistosomiasis after leisure activities in infested freshwater. (the water sports enthusiast returning from a sojourn on Lake Malawi .... are harbouring a 'blind passenger' from abroad. However, long-term travellers, both private or business, should be screened on return. A thorough ...

  5. Sealed Planetary Return Canister (SPRC), Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Sample return missions have primary importance in future planetary missions. A basic requirement is that samples be returned in pristine, uncontaminated condition,...

  6. How East Asian westerly jet's meridional position affects the summer rainfall in Yangtze-Huaihe River Valley?

    Science.gov (United States)

    Wang, Shixin; Zuo, Hongchao; Zhao, Shuman; Zhang, Jiankai; Lu, Sha

    2017-03-01

    Existing studies show that the change in the meridional position of East Asian westerly jet (EAWJ) is associated with rainfall anomalies in Yangtze-Huaihe River Valley (YHRV) in summer. However, the dynamic mechanism has not been resolved yet. The present study reveals underlying mechanisms for this impact for early summer and midsummer, separately. Mechanism1: associated with EAWJ's anomalously southward displacement, the 500-hPa westerly wind over YHRV is strengthened through midtropospheric horizontal circulation anomalies; the westerly anomalies are related to the formation of warm advection anomalies over YHRV, which cause increased rainfall through adiabatic ascent motion and convective activities; the major difference in these processes between early summer and midsummer is the midtropospheric circulation anomaly pattern. Mechanism 2: associated with EAWJ's anomalously southward displacement, the large day-to-day variability of midtropospheric temperature advection in midlatitudes is displaced southward by the jet's trapping transient eddies; this change enhances the day-to-day variability of temperature advection over YHRV, which in turn causes the increased rainfall in most part of YHRV through "lower-bound effect" (rainfall amount can not become negative); there is not much difference in these processes between early summer and midsummer.

  7. Flow-through shares for power development

    International Nuclear Information System (INIS)

    Howie, K.D.

    1999-01-01

    Financial advantages will occur to power producers in Ontario provided that they are innovative in raising capital needed to take advantage of opportunities offered by the Energy Competition Act of 1998. In the new electricity regime, the availability of long term non-recourse debt financing supported by long term power purchasing from Ontario Hydro will probably decrease. The issuance of flow-through shares is a form of financing that could by available to them for certain projects, and there is the probability that greater equity financing will be needed. These flow-through shares can give investors immediate tax savings, a potential favorable return on their equity investment, and a means of financing certain kinds of power projects

  8. Surface mapping, organic matter and water stocks in peatlands of the Serra do Espinhaço meridional - Brazil

    Directory of Open Access Journals (Sweden)

    Márcio Luiz da Silva

    2013-10-01

    Full Text Available Peatlands are soil environments that store carbon and large amounts of water, due to their composition (90 % water, low hydraulic conductivity and a sponge-like behavior. It is estimated that peat bogs cover approximately 4.2 % of the Earth's surface and stock 28.4 % of the soil carbon of the planet. Approximately 612 000 ha of peatlands have been mapped in Brazil, but the peat bogs in the Serra do Espinhaço Meridional (SdEM were not included. The objective of this study was to map the peat bogs of the northern part of the SdEM and estimate the organic matter pools and water volume they stock. The peat bogs were pre-identified and mapped by GIS and remote sensing techniques, using ArcGIS 9.3, ENVI 4.5 and GPS Track Maker Pro software and the maps validated in the field. Six peat bogs were mapped in detail (1:20,000 and 1:5,000 by transects spaced 100 m and each transect were determined every 20 m, the UTM (Universal Transverse Mercator coordinates, depth and samples collected for characterization and determination of organic matter, according to the Brazilian System of Soil Classification. In the northern part of SdEM, 14,287.55 ha of peatlands were mapped, distributed over 1,180,109 ha, representing 1.2 % of the total area. These peatlands have an average volume of 170,021,845.00 m³ and stock 6,120,167 t (428.36 t ha-1 of organic matter and 142,138,262 m³ (9,948 m³ ha-1 of water. In the peat bogs of the Serra do Espinhaço Meridional, advanced stages of decomposing (sapric organic matter predominate, followed by the intermediate stage (hemic. The vertical growth rate of the peatlands ranged between 0.04 and 0.43 mm year-1, while the carbon accumulation rate varied between 6.59 and 37.66 g m-2 year-1. The peat bogs of the SdEM contain the headwaters of important water bodies in the basins of the Jequitinhonha and San Francisco Rivers and store large amounts of organic carbon and water, which is the reason why the protection and preservation

  9. Numerical and experimental flow analysis in centifluidic systems for rapid allergy screening tests

    Directory of Open Access Journals (Sweden)

    Dethloff Manuel

    2015-09-01

    Full Text Available For the development of the automated processing of a membrane-based rapid allergy test, the flow characteristics in one part of the test, the reagents module, are analysed. This module consists of a multichannel system with several inputs and one output. A return flow from one input channel into another should be avoided. A valveless module with pointed channels at an angle of 12° is analysed with numerical and experimental methods with regard to the flow characteristics.

  10. Product return management

    DEFF Research Database (Denmark)

    Shaharudin, Mohd Rizaimy; Govindan, Kannan; Zailani, Suhaiza

    2017-01-01

    The aim of this study is to examine the extent to which product returns motivate manufacturing firms to adopt closed-loop supply chain activities that influence the effectiveness of reverse supply chains. The hypotheses have been tested using data from a sample of 150 environmental management...... system ISO 14001 certified manufacturing firms in Malaysia through the census sampling approach. The results of the empirical test using LISREL Version 8.70 for the structural equation modeling support the fundamental explanation of the influence of the institutional forces towards the adoption of closed...... eventually impacts the firm's effectiveness in the reverse supply chain. The findings also help managers to understand the factors that can improve the outcome of the adoption of closed-loop supply chain activities by intensifying the extent of involvement in product returns, which provides a valuable...

  11. 76 FR 17521 - Specified Tax Return Preparers Required To File Individual Income Tax Returns Using Magnetic Media

    Science.gov (United States)

    2011-03-30

    ... regulations reflect changes made to the law by the Worker, Homeownership, and Business Assistance Act of 2009... definition of a ``specified tax return preparer'' must electronically file Federal income tax returns that... of the Worker, Homeownership, and Business Assistance Act of 2009 (Pub. L. 111-92 (123 Stat. 2984...

  12. Stock returns and foreign investment in Brazil

    OpenAIRE

    Reis, Luciana; Meurer, Roberto; Da Silva, Sergio

    2008-01-01

    We examine the relationship between stock returns and foreign investment in Brazil, and find that the inflows of foreign investment boosted the returns from 1995 to 2005. There was a strong contemporaneous correlation, although not Granger-causality. Foreign investment along with the exchange rate, the influence of the world stock markets, and country risk can explain 73 percent of the changes that occurred in the stock returns over the period. We also find that positive feedback trading play...

  13. INSTITUTIONAL OWNERSHIP LEVEL AND RISK-ADJUSTED RETURN

    OpenAIRE

    Isaiah, Chioma; Li, Meng (Emma)

    2017-01-01

    This paper examines the relationship between the level of institutional ownership andrisk-adjusted return on stocks. We find a significant positive relationship between the level ofinstitutional ownership on a stock and its risk-adjusted return. This result holds both in the longrun and in shorter time periods. Our findings suggest that all things being equal, it is possible toobtain risk-adjusted return by going short on the stocks with low institutional ownership andgoing long on those with...

  14. 76 FR 36996 - Extension of Time for Filing Returns

    Science.gov (United States)

    2011-06-24

    ... less time to complete accurate income tax returns and to provide timely information to the trust's... either chapter 7 or chapter 11 of Title 11 of the U.S. Code that is required to file an income tax return... estate or trust income tax return or failure to pay the amount shown as tax on the return. (g) Effective...

  15. Early actions of cadmium in the rat and domestic fowl. VI. Testicular and muscle blood flow changes

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, A D; Turner, P C

    1972-01-01

    Male rats and domestic fowl were injected subcutaneously with 0.03 m-moles cadmium chloride (Cd)/kg body weight with some rats previously pre-treated with zinc acetate (Zn). Early relative blood flow changes were studied. In the fowl no blood flow changes were detected due to Cd. In the rat Cd resulted in a sharp increase in blood flow to the testis at 2.5 and 10 min after Cd followed by a return toward normal. Zn pre-treatment resulted in blood flow which was higher than in untreated rats. However, when this pre-treatment was followed by Cd the sharp changes in blood flow, found in rats treated with Cd but without Zn pre-treatment, were not manifest. This also resulted in a more rapid return to control levels. Cd acts on the vasculature of the testis of the rat but not that of the domestic fowl and Zn pre-treatment in the rat moderates the action of Cd on the vasculature. 15 references, 2 figures.

  16. 27 CFR 41.112 - Tax return.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Tax return. 41.112 Section 41.112 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF... States Deferred Payment of Tax in Puerto Rico on Tobacco Products § 41.112 Tax return. The internal...

  17. [Organising a successful return home].

    Science.gov (United States)

    Mézière, Anthony

    Discharge from hospital is a major component of the quality and efficiency of the healthcare system. The failures of the return home of elderly people testify to the difficulties of applying guidelines in the area of hospital discharge. The action plan decided in the hospital for a successful return home can be jeopardised for personal, relational, functional and structural reasons originating from the different players involved in the hospital discharge. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  18. Capital Structure and Stock Returns

    OpenAIRE

    Ivo Welch

    2002-01-01

    U.S. corporations do not issue and repurchase debt and equity to counteract the mechanistic effects of stock returns on their debt-equity ratios. Thus over one- to five-year horizons, stock returns can explain about 40 percent of debt ratio dynamics. Although corporate net issuing activity is lively and although it can explain 60 percent of debt ratio dynamics (long-term debt issuing activity being most capital structurerelevant), corporate issuing motives remain largely a mystery. When stock...

  19. News and Views: Kleopatra a pile of rubble, shedding moons; Did plasma flow falter to stretch solar minimum? Amateurs hit 20 million variable-star observations; Climate maths; Planetary priorities; New roles in BGA

    Science.gov (United States)

    2011-04-01

    Metallic asteroid 216 Kleopatra is shaped like a dog's bone and has two tiny moons - which came from the asteroid itself - according to a team of astronomers from France and the US, who also measured its surprisingly low density and concluded that it is a collection of rubble. The recent solar minimum was longer and lower than expected, with a low polar field and an unusually large number of days with no sunspots visible. Models of the magnetic field and plasma flow within the Sun suggest that fast, then slow meridional flow could account for this pattern. Variable stars are a significant scientific target for amateur astronomers. The American Association of Variable Star Observers runs the world's largest database of variable star observations, from volunteers, and reached 20 million observations in February.

  20. Return Migration among Elderly, Chronically Ill Bosnian Refugees

    DEFF Research Database (Denmark)

    Handlos, Line Neerup; Olwig, Karen Fog; Bygbjerg, Ib Christian

    2015-01-01

    Elderly migrants constitute a considerable share of global return migration; nevertheless, literature on the health aspects of the return migration among these migrants is still scarce. This study explores the significance of return migration among elderly, chronically ill Bosnian refugees from...... Denmark and the role of health issues in their decision to return. It is based on semi-structured interviews with 33 elderly, chronically ill Bosnian refugees who have moved back to Bosnia and Herzegovina, and 10 elderly, chronically ill Bosnian refugees who have remained in Denmark. The interviews show...

  1. Mobility, return for development and sense of Europe: narratives of Moldavian immigrants returning from the European Union

    Directory of Open Access Journals (Sweden)

    Silvia Marcu

    Full Text Available The article links migration, cross-border mobility and return for development embedded in terms of identity and approach to sense of Europe. Taking into account the global changes in Moldova, the paper examines the perceptions of mobility, return and identity of the Moldovans engaged in emigration in the countries of the European Union (EU. Utilising a multi-discipline approach and an in-depth qualitative interview technique, this article seeks to analyze how mobility and return can support social change and development of the country, and argues that people, who cross EU borders, living through the experience of emigration, acquire a pro-European mentality.

  2. RETURNS OF PRIVATE EQUITY COMPARATIVE ANALYSES OF THE RETURNS OF VENTURE CAPITAL AND BUYOUT FUNDS IN EUROPE AND IN THE US

    Directory of Open Access Journals (Sweden)

    Becsky-Nagy Patrícia

    2014-07-01

    Full Text Available This paper focuses on the returns of two segments of Private Equity (PE market in Europe and in the US; Venture Capital (VC and Buyout (BO. Contrary to the publicly traded stocks where information about the trade of securities is public, the measuring of the returns of these asset classes is not unambiguous. The returns of PE investments are considered as confidential information therefore we only have estimations about the real characteristics of the financial performance of the PE industry. Although it is impossible to observe the whole industry it is important to chart its performance because PE plays an essential role in the financing of firms, especially firms at special stages of their lives and the more information the investors and companies have, the more effective PE market can be therefore it can contribute to economic growth, employment, innovation etc. In the literature PE, VC and BO are not distinguished properly and they are often used as synonyms. Despite their similarities, there are significant differences in the features of these types of investments. In this paper the authors present the return characteristics of the PE industry of Europe and the US with regard to the stage-focus of PE funds. The key findings of this paper are that in average the returns of BO funds exceeded the returns of VC funds in the US as well as in Europe. Not just according to the absolute value of the returns, but also according to its risk-return tradeoff BO seems to be a preferable investment. The same statements can be made in case of the European market. The US returns are higher than European VC returns, because compared to the US VC industry the European is undeveloped. On the other hand the gap between the performances of BO funds is not as significant as the difference of VC funds. While in the 90’s US BO funds outperformed the European ones, after the millennia European BO returns were higher. The analysis of returns reveals the

  3. 14 CFR 49.21 - Return of original conveyance.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Return of original conveyance. 49.21... RECORDING OF AIRCRAFT TITLES AND SECURITY DOCUMENTS General § 49.21 Return of original conveyance. If a person submitting a conveyance for recording wants the original returned to him, he must submit a true...

  4. FINANCIAL RETURN ON ASSETS. THE IMPACT OF THE FINANCIAL RETURN ON ASSETS OVER THE COMPANY’S DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Constantin Căruntu

    2009-11-01

    Full Text Available The financial rate of return is a significant indicator for assessing the economic and financial performance of an enterprise for the internal diagnosis, as well as for the analysis required by the external partners. The financial return is a basic indicator which characterizes the business performances that is found directly under the trade policy (trade cost, efficiency of capital employed (economic profitability but also under the financial policy of the company. If the economic rate of return expresses a remuneration of the employed capital only in relation to operating activities, the financial rate of return quantifies a remuneration of the private capital trough all three types of activity: operational, financial and extraordinary. Starting from the consideration that the financial rate of return expresses the efficiency of equity or permanent capital use of the company we can state that it is of particular importance to the shareholders of the company, which considers according to it’s level whether their investments are justified and they will continue to support the business development through raising of fresh capital or abandonment for a limited period to one part of the dividends due. Managers, in turn, will be keen on maintaining an appropriate level of this rate, in order to retain their positions and to achieve the performance criteria of the company.

  5. Tracing fluid flow in geothermal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Rose, P.E.; Adams, M.C. [Univ. of Utah, Salt Lake City, UT (United States)

    1997-12-31

    A family of fluorescent compounds, the polycyclic aromatic sulfonates, were evaluated for application in intermediate- and high-temperature geothermal reservoirs. Whereas the naphthalene sulfonates were found to be very thermally stable and reasonably detectable, the amino-substituted naphthalene sulfonates were found to be somewhat less thermally stable, but much more detectable. A tracer test was conducted at the Dixie Valley, Nevada, geothermal reservoir using one of the substituted naphthalene sulfonates, amino G, and fluorescein. Four of 9 production wells showed tracer breakthrough during the first 200 days of the test. Reconstructed tracer return curves are presented that correct for the thermal decay of tracer assuming an average reservoir temperature of 227{degrees}C. In order to examine the feasibility of using numerical simulation to model tracer flow, we developed simple, two-dimensional models of the geothermal reservoir using the numerical simulation programs TETRAD and TOUGH2. By fitting model outputs to measured return curves, we show that numerical reservoir simulations can be calibrated with the tracer data. Both models predict the same order of elution, approximate tracer concentrations, and return curve shapes. Using these results, we propose a method for using numerical models to design a tracer test.

  6. Measurement of LBE flow velocity profile by UDVP

    International Nuclear Information System (INIS)

    Kikuchi, Kenji; Takeda, Yasushi; Obayashi, Hiroo; Tezuka, Masao; Sato, Hiroshi

    2006-01-01

    Measurements of liquid metal lead-bismuth eutectic (LBE), flow velocity profile were realized in the spallation neutron source target model by the ultrasonic Doppler velocity profiler (UVDP) technique. So far, it has not been done well, because both of poor wetting property of LBE with stainless steels and poor performance of supersonic probes at high temperatures. The measurement was made for a return flow in the target model, which has coaxially arranged annular and tube channels, in the JAEA Lead Bismuth Loop-2 (JLBL-2). The surface treatment of LBE container was examined. It was found that the solder coating was effective to enhance an intensity of reflected ultrasonic wave. This treatment has been applied to the LBE loop, which was operated up to 150 deg. C. The electro magnetic pump generates LBE flow and the flow rate was measured by the electro magnetic flow meter. By changing the flow rate of LBE, velocity profiles in the target were measured. It was confirmed that the maximum velocity in the time-averaged velocity distribution on the target axis was proportional to the flow rate measured by the electro magnetic flow meter

  7. 27 CFR 25.211 - Beer returned to brewery.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Beer returned to brewery..., DEPARTMENT OF THE TREASURY LIQUORS BEER Beer Returned to Brewery § 25.211 Beer returned to brewery. (a) General. Beer, produced in the United States, on which the brewer has paid or determined the tax may be...

  8. Returning to sports after a back injury

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000518.htm Returning to sports after a back injury To use the sharing ... Back pain - returning to sports Which Type of Sport is Best? In deciding when and if to ...

  9. The Extinction and Return of Fear of Public Speaking.

    Science.gov (United States)

    Laborda, Mario A; Schofield, Casey A; Johnson, Emily M; Schubert, Jessica R; George-Denn, Daniel; Coles, Meredith E; Miller, Ralph R

    2016-11-01

    Prior studies indicate extinguished fear often partially returns when participants are later tested outside the extinction context. Cues carried from the extinction context to the test context sometimes reduce return of fear, but it is unclear whether such extinction cues (ECs) reduce return of fear of public speaking. Here we assessed return of fear of public speaking, and whether either of two types of ECs can attenuate it. Participants gave speeches of increasing difficulty during an exposure practice session and were tested 2 days later in a different context. Testing occurred in the presence of physical ECs, after mentally rehearsing the exposure session, or without either reminder. Practice reduced fear of public speaking, but fear partially returned at test. Neither physical nor mental ECs reduced partial return of fear of public speaking. The return of extinguished fear of public speaking, although small, was reliable, but not appreciably sensitive to presence of ECs. © The Author(s) 2016.

  10. Local justice and power of an official nature in Southern Sudan. = La justicia local y el poder de la oficialidad en el Sudán Meridional.

    OpenAIRE

    Leonardi, Cherry

    2009-01-01

    En este artículo se expone la ambigüedad creciente que caracteriza la administración de justicia en el Sudan Meridional desde que, gracias a los acuerdos de paz de 2005, se puso en marcha un gobierno autónomo. Mientras el Estado fue un ente lejano y ajeno por el monopolio que ejercían sobre él las poblaciones del norte, sus tribunales de justicia, por precarios que fueran, pudieron ser vistos en el sur como un agente neutral, en tanto que distanciado de las redes de poder locales: era el cons...

  11. Return Migration and Working Choices

    OpenAIRE

    TANI, Massimiliano; MAHUTEAU, Stéphane

    2008-01-01

    Collective Action to Support the Reintegration of Return Migrants in their Country of Origin (MIREM) This paper uses the recent survey carried out in the framework of the MIREM project on returnees to Algeria, Morocco and Tunisia and studies the duration of emigration and the labour force status upon returning. The results suggest that age and the year of emigration play a central role in the migration decision, but they do not support the hypothesis that the duration of migration is deter...

  12. Slow return of displaced Southern Sudanese

    Directory of Open Access Journals (Sweden)

    Tim Morris

    2007-07-01

    Full Text Available The pace of repatriation of Sudanese refugees and return of IDP s to South Sudan has picked up but expectations at the time of the signing of the Comprehensive Peace Agreement (CPA CPA in January 2005 have yet to be realised. With all eyes on Darfur, assistance to sustain returns to South Sudan remains inadequate.

  13. 31 CFR 10.28 - Return of client's records.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Return of client's records. 10.28... § 10.28 Return of client's records. (a) In general, a practitioner must, at the request of a client, promptly return any and all records of the client that are necessary for the client to comply with his or...

  14. Energy flow theory of nonlinear dynamical systems with applications

    CERN Document Server

    Xing, Jing Tang

    2015-01-01

    This monograph develops a generalised energy flow theory to investigate non-linear dynamical systems governed by ordinary differential equations in phase space and often met in various science and engineering fields. Important nonlinear phenomena such as, stabilities, periodical orbits, bifurcations and chaos are tack-led and the corresponding energy flow behaviors are revealed using the proposed energy flow approach. As examples, the common interested nonlinear dynamical systems, such as, Duffing’s oscillator, Van der Pol’s equation, Lorenz attractor, Rössler one and SD oscillator, etc, are discussed. This monograph lights a new energy flow research direction for nonlinear dynamics. A generalised Matlab code with User Manuel is provided for readers to conduct the energy flow analysis of their nonlinear dynamical systems. Throughout the monograph the author continuously returns to some examples in each chapter to illustrate the applications of the discussed theory and approaches. The book can be used as ...

  15. DETERMINANTS OF RETURN ON EQUITY OF COOPERATIVE BANKS IN POLAND

    Directory of Open Access Journals (Sweden)

    Anna Bieniasz

    2016-03-01

    Full Text Available The aim of the study was to analyse the diversity of return on equity in the cooperative banks in Poland in 2010– 2014. The analysis was conducted using data of the Polish Financial Supervision Authority, on the basis of a modifi ed decomposition rate of return on equity. Assessment of the rate of return on equity was made in a size of banks, as determined by the value of assets. In addition, in order to determine the strength and direction of impact the individual components of the model on the formation of return on equity method was applied functional. The study suggests that cooperative banks eff ectively use the equity, because the rate of return on equity was signifi cantly higher than the rate of return on assets. The average return on assets in 2010–2014 was relatively lower in the largest banks and ranged from 0.7–0.9%, and the smallest banks return on assets was approximately 1%. In turn, the return on equity was higher at banks with major assets (over 200 million PLN. In 2013–2014 the rate of return both on assets and equity expressly declined. The main determinants of changes in return on equity were changing the multiplier reduction of profi t from banking activities by operating costs and costs of banking risk and return on assets, as well as measured result on banking activities.

  16. Abnormal Returns and Contrarian Strategies

    Directory of Open Access Journals (Sweden)

    Ivana Dall'Agnol

    2003-12-01

    Full Text Available We test the hypothesis that strategies which are long on portfolios of looser stocks and short on portfolios of winner stocks generate abnormal returns in Brazil. This type of evidence for the US stock market was interpreted by The Bondt and Thaler (1985 as reflecting systematic evaluation mistakes caused by investors overreaction to news related to the firm performance. We found evidence of contrarian strategies profitability for horizons from 3 months to 3 years in a sample of stock returns from BOVESPA and SOMA from 1986 to 2000. The strategies are more profitable for shorter horizons. Therefore, there was no trace of the momentum effect found by Jagadeesh and Titman (1993 for the same horizons with US data. There are remaing unexplained positive returns for contrarian strategies after accounting for risk, size, and liquidity. We also found that the strategy profitability is reduced after the Real Plan, which suggests that the Brazilian stock market became more efficient after inflation stabilization.

  17. Factor Structure in Commodity Futures Return and Volatility

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Lunde, Asger; Olesen, Kasper Vinther

    Using data on more than 750 million futures trades during 2004-2013, we analyze eight stylized facts of commodity price and volatility dynamics in the post financialization period. We pay particular attention to the factor structure in returns and volatility and to commodity market integration...... with the equity market. We find evidence of a factor structure in daily commodity futures returns. However, the factor structure in daily commodity futures volatility is even stronger than in returns. When computing model-free realized commodity betas with the stock market we find that they were high during 2008......-2010 but have since returned to the pre-crisis level close to zero. The common factor in commodity volatility is nevertheless clearly related to stock market volatility. We conclude that, while commodity markets appear to again be segmented from the equity market when only returns are considered, commodity...

  18. Estimation of return levels against different return periods of extreme annual rainfall over Baluchistan

    International Nuclear Information System (INIS)

    Ali, M.; Jan, B.; Iqbal, J.

    2012-01-01

    Unprecedented heavy monsoon rainfall began in the last week of July 2010 in the Northern part of our country, causes floods in Baluchistan and Sindh. As the high frequency rainfall events are a significant cause of current severe flooding in Pakistan and any fluctuation in the level of such events may cause huge economic losses as well as social problem, urban structures (i.e. dams, urban drainage systems and flood). Statistical distributions are used to identify extremes of annual rainfall of different cities of Baluchistan (Quetta, Sibbi, Khuzdar, Lasbella, Dalbandin and Pasni) with their return periods. Analysis predicts that Gumbel Max. (GM) Distribution is the best fitted distribution for Sibbi and Lasbella while the GEV distribution is the best fitted for Quetta, Khuzdar, Dalbandin and Pasni. The analysis also suggests that different cities of Baluchistan have 30-years return period for getting more than 90 mm average daily rainfall while they have 100-years return period for receiving more than 118 mm daily rainfall. This suggests for suitable flood forecasting and improving the river structure in Baluchistan, Pakistan. (author)

  19. Generation of the lower-thermospheric vertical wind estimated with the EISCAT KST radar at high latitudes during periods of moderate geomagnetic disturbance

    Directory of Open Access Journals (Sweden)

    S. Oyama

    2008-06-01

    Full Text Available Lower-thermospheric winds at high latitudes during moderately-disturbed geomagnetic conditions were studied using data obtained with the European Incoherent Scatter (EISCAT Kiruna-Sodankylä-Tromsø (KST ultrahigh frequency (UHF radar system on 9–10 September 2004. The antenna-beam configuration was newly designed to minimize the estimated measurement error of the vertical neutral-wind speed in the lower thermosphere. This method was also available to estimate the meridional and zonal components. The vertical neutral-wind speed at 109 km, 114 km, and 120 km heights showed large upward motions in excess of 30 m s−1 in association with an ionospheric heating event. Large downward speeds in excess of −30 m s−1 were also observed before and after the heating event. The meridional neutral-wind speed suddenly changed its direction from equatorward to poleward when the heating event began, and then returned equatorward coinciding with a decrease in the heating event. The magnetometer data from northern Scandinavia suggested that the center of the heated region was located about 80 km equatorward of Tromsø. The pressure gradient caused the lower-thermospheric wind to accelerate obliquely upward over Tromsø in the poleward direction. Acceleration of the neutral wind flowing on a vertically tilted isobar produced vertical wind speeds larger by more than two orders of magnitude than previously predicted, but still an order of magnitude smaller than observed speeds.

  20. Generation of the lower-thermospheric vertical wind estimated with the EISCAT KST radar at high latitudes during periods of moderate geomagnetic disturbance

    Directory of Open Access Journals (Sweden)

    S. Oyama

    2008-06-01

    Full Text Available Lower-thermospheric winds at high latitudes during moderately-disturbed geomagnetic conditions were studied using data obtained with the European Incoherent Scatter (EISCAT Kiruna-Sodankylä-Tromsø (KST ultrahigh frequency (UHF radar system on 9–10 September 2004. The antenna-beam configuration was newly designed to minimize the estimated measurement error of the vertical neutral-wind speed in the lower thermosphere. This method was also available to estimate the meridional and zonal components. The vertical neutral-wind speed at 109 km, 114 km, and 120 km heights showed large upward motions in excess of 30 m s−1 in association with an ionospheric heating event. Large downward speeds in excess of −30 m s−1 were also observed before and after the heating event. The meridional neutral-wind speed suddenly changed its direction from equatorward to poleward when the heating event began, and then returned equatorward coinciding with a decrease in the heating event. The magnetometer data from northern Scandinavia suggested that the center of the heated region was located about 80 km equatorward of Tromsø. The pressure gradient caused the lower-thermospheric wind to accelerate obliquely upward over Tromsø in the poleward direction. Acceleration of the neutral wind flowing on a vertically tilted isobar produced vertical wind speeds larger by more than two orders of magnitude than previously predicted, but still an order of magnitude smaller than observed speeds.

  1. Inventory control with product returns : The impact of imperfect information

    NARCIS (Netherlands)

    De Brito, M.P.; Laan, E.A.

    2009-01-01

    Product returns are characterized by considerable uncertainty on time and quantity. In the literature on inventory management for product return environments best forecasts of future returns are associated with methods that use the most information regarding product return history. In practice,

  2. 26 CFR 301.6103(j)(1)-1T - Disclosures of return information reflected on returns to officers and employees of the...

    Science.gov (United States)

    2010-04-01

    ... related activities (temporary). 301.6103(j)(1)-1T Section 301.6103(j)(1)-1T Internal Revenue INTERNAL... ADMINISTRATION Information and Returns Returns and Records § 301.6103(j)(1)-1T Disclosures of return information... § 301.6103(j)(1)-1(a) through (b)(3)(xxiv). (xxv) From Form 6765 (when filed with corporation income tax...

  3. Planetary protection considerations for sample-return missions

    Science.gov (United States)

    Rummel, J.

    The analysis on Earth of materials returned from other solar system bodies, and beyond, is likely one of the most effective ways for us to learn about the origins, history, and present state of the universe outside of our home planet. In the past, the Apollo missions were able to return large quantities of material from the Moon, while missions currently flying (Genesis and Stardust) intend to return much smaller quantities of material. Planned and conceptualized future missions (cf., MUSES-C) intend to return a wide variety of samples such as those from a near-Earth asteroid, the surface and atmosphere of Mars , and perhaps once more from the Earth's Moon. In some cases, the bodies targeted for sample return missions may have the capability of harboring indigenous life, while in other cases there is scant possibility of that. Considerations in determining the potential for extraterrestrial contamination from sample return missions have been studied, and include such factors as the availability of liquid water in or on the target body, the availability of m tabolicallye useful energy sources, the likelihood that organic matter was available, and the overall temperature and radiation history of the sampled areas. Also of note is the potential that the natural influx to Earth of that materials in question (e.g., meteorites, etc.) might overwhelm the ability of a targeted sample-return mission to contribute something novel to the Earth's environment. Missions thought to pose a risk of extraterrestrial biological contamination are subject to a containment provision that may be very difficult to implement on a single, moderate-cost mission, but such steps are necessary to protect both our own planet and the health of solar-system exploration missions and the science they can do.

  4. One-Step Direct Return Method For Mohr-Coulomb Plasticity

    DEFF Research Database (Denmark)

    Clausen, Johan; Damkilde, Lars; Andersen, Lars

    2004-01-01

    A new return method for the Mohr-Coulomb yield criteria is presented. The idea is to transform the problem into the principal direction and thereby achieve very simple formulas for calculating the elastic return stresses.......A new return method for the Mohr-Coulomb yield criteria is presented. The idea is to transform the problem into the principal direction and thereby achieve very simple formulas for calculating the elastic return stresses....

  5. Cerebral pressure-flow relationship in lowlanders and natives at high altitude.

    Science.gov (United States)

    Smirl, Jonathan D; Lucas, Samuel J E; Lewis, Nia C S; duManoir, Gregory R; Dumanior, Gregory R; Smith, Kurt J; Bakker, Akke; Basnyat, Aperna S; Ainslie, Philip N

    2014-02-01

    We investigated if dynamic cerebral pressure-flow relationships in lowlanders are altered at high altitude (HA), differ in HA natives and after return to sea level (SL). Lowlanders were tested at SL (n=16), arrival to 5,050 m, after 2-week acclimatization (with and without end-tidal PO2 normalization), and upon SL return. High-altitude natives (n=16) were tested at 5,050 m. Testing sessions involved resting spontaneous and driven (squat-stand maneuvers at very low (VLF, 0.05 Hz) and low (LF, 0.10 Hz) frequencies) measures to maximize blood pressure (BP) variability and improve assessment of the pressure-flow relationship using transfer function analysis (TFA). Blood flow velocity was assessed in the middle (MCAv) and posterior (PCAv) cerebral arteries. Spontaneous VLF and LF phases were reduced and coherence was elevated with acclimatization to HA (Pflow coupling. However, when BP was driven, both the frequency- and time-domain metrics were unaltered and comparable with HA natives. Acute mountain sickness was unrelated to TFA metrics. In conclusion, the driven cerebral pressure-flow relationship (in both frequency and time domains) is unaltered at 5,050 m in lowlanders and HA natives. Our findings indicate that spontaneous changes in TFA metrics do not necessarily reflect physiologically important alterations in the capacity of the brain to regulate BP.

  6. HUBUNGAN RETURN SAHAM DAN INFLASI DI INDONESIA

    Directory of Open Access Journals (Sweden)

    Nyoman Triaryati

    2017-03-01

    Full Text Available The effect of inflation to the stock return research had been held since three decades ago based on GeneralizeFisher’s Hypotheses, but ‘how inflation influenced stock return’ had become a debate until today. In Indonesiamost of the related research used inflation as one of the variables that influenced stock return despite of others inshort period of time. This research investigated the effect of inflation to the stock return in Indonesia within fifteenyears, which was divided into 3 (three periods of time reflecting different economic growth for each of it. Thepurpose of this allotment was to see the consistency how inflation influenced the stock market. Using a secondarydata from monthly inflation and IHSG period 1998 until 2012, included three hundred and sixty observation,simple regression model analyses was applied. This research acknowledged that inflation negatively influencedstock return in a long time period, but it did not exist in the short time period, except when the level of inflationreached 10%. In conclusion, inflation influence on the stock return was not ascertained by how long the investigationwas held but if there was any inflation rate reaching 10% within the period of investigation.

  7. Habit formation, surplus consumption and return predictability

    DEFF Research Database (Denmark)

    Engsted, Tom; Hyde, Stuart; Vinther Møller, Stig

    2010-01-01

    On an international post World War II dataset, we use an iterated GMM procedure to estimate and test the Campbell and Cochrane (1999, By force of habit: a consumption-based explanation of aggregate stock market behavior. Journal of Political Economy 107, 205–251.) habit formation model with a time......-varying risk-free rate. In addition, we analyze the predictive power of the surplus consumption ratio for future stock and bond returns. We find that, although there are important cross-country differences and economically significant pricing errors, for the majority of countries in our sample the model gets...... significant information about future stock returns, also during the 1990s. In addition, in most countries the surplus consumption ratio is also a powerful predictor of future bond returns. Thus, the surplus consumption ratio captures time-varying expected returns in both stock and bond markets....

  8. Dynamic returns of beta arbitrage

    OpenAIRE

    Nascimento, Mafalda

    2017-01-01

    This thesis studies the patterns of the abnormal returns of the beta strategy. The topic can be helpful for professional investors, who intend to achieve a better performance in their portfolios. Following the methodology of Lou, Polk, & Huang (2016), the COBAR measure is computed in order to determine the levels of beta arbitrage in the market in each point in time. It is argued that beta arbitrage activity can have impact on the returns of the beta strategy. In fact, it is demonstrated that...

  9. Determination of the catalyst circulation rate in a FCC cold flow pilot unit using nuclear techniques

    International Nuclear Information System (INIS)

    Santos, Valdemir A. dos; Lima, Emerson A.O.

    2013-01-01

    Nuclear techniques of gamma transmission and radioactive tracer were used to estimate the catalyst circulation rate in a cold flow pilot plant unit of Fluid Catalytic Cracking (FCC). Catalyst circulation rate in a FCC unit, allow to determine operating conditions of the exchange catalyst and inlet data for fluid dynamic simulation computational program. The pilot unit was fabricated obeying geometrical parameters provided by the Petrobras Research Center (CENPES), based on hot pilot units to existing in that center. The cold flow pilot unit has a transfer line, two separation vessels flash type, a return column, a riser and a regenerator. The vertical sections as riser, return column, regenerator column and transfer line are made of transparent material (glass). The two separation vessels have bases with tapered cylindrical shapes and are made of steel plates. The riser is divided into four sections of different diameters (0.005 m, 0.010 m, 0.018 m and 0.025 m) and rising upwards, to simulate the increasing flow rate caused by the increase of volume with the increase of the number of moles due to molecules breakage. The radioactive tracer used was the catalyst itself (intrinsic tracer) irradiated by neutron activation, yielding the radioisotope 59 Fe. The velocity measurements were also obtained with aid of an electronic clock triggered by certain radiation levels across the two detectors. Besides estimates for the catalyst circulation rate was possible to identify the type of flow relative to the catalyst in return column. (author)

  10. Returns on Investment in California County Departments of Public Health.

    Science.gov (United States)

    Brown, Timothy T

    2016-08-01

    To estimate the average return on investment for the overall activities of county departments of public health in California. I gathered the elements necessary to estimate the average return on investment for county departments of public health in California during the period 2001 to 2008-2009. These came from peer-reviewed journal articles published as part of a larger project to develop a method for determining return on investment for public health by using a health economics framework. I combined these elements by using the standard formula for computing return on investment, and performed a sensitivity analysis. Then I compared the return on investment for county departments of public health with the returns on investment generated for various aspects of medical care. The estimated return on investment from $1 invested in county departments of public health in California ranges from $67.07 to $88.21. The very large estimated return on investment for California county departments of public health relative to the return on investment for selected aspects of medical care suggests that public health is a wise investment.

  11. Oil Volatility Risk and Expected Stock Returns

    DEFF Research Database (Denmark)

    Christoffersen, Peter; Pan, Xuhui (Nick)

    After the financialization of commodity futures markets in 2004-05 oil volatility has become a strong predictor of returns and volatility of the overall stock market. Furthermore, stocks' exposure to oil volatility risk now drives the cross-section of expected returns. The difference in average...... return between the quintile of stocks with low exposure and high exposure to oil volatility is significant at 0.66% per month, and oil volatility risk carries a significant risk premium of -0.60% per month. In the post-financialization period, oil volatility risk is strongly related with various measures...

  12. An update of Leighton's solar dynamo model

    Science.gov (United States)

    Cameron, R. H.; Schüssler, M.

    2017-03-01

    In 1969, Leighton developed a quasi-1D mathematical model of the solar dynamo, building upon the phenomenological scenario of Babcock published in 1961. Here we present a modification and extension of Leighton's model. Using the axisymmetric component (longitudinal average) of the magnetic field, we consider the radial field component at the solar surface and the radially integrated toroidal magnetic flux in the convection zone, both as functions of latitude. No assumptions are made with regard to the radial location of the toroidal flux. The model includes the effects of (I) turbulent diffusion at the surface and in the convection zone; (II) poleward meridional flow at the surface and an equatorward return flow affecting the toroidal flux; (III) latitudinal differential rotation and the near-surface layer of radial rotational shear; (iv) downward convective pumping of magnetic flux in the shear layer; and (v) flux emergence in the form of tilted bipolar magnetic regions treated as a source term for the radial surface field. While the parameters relevant for the transport of the surface field are taken from observations, the model condenses the unknown properties of magnetic field and flow in the convection zone into a few free parameters (turbulent diffusivity, effective return flow, amplitude of the source term, and a parameter describing the effective radial shear). Comparison with the results of 2D flux transport dynamo codes shows that the model captures the essential features of these simulations. We make use of the computational efficiency of the model to carry out an extended parameter study. We cover an extended domain of the 4D parameter space and identify the parameter ranges that provide solar-like solutions. Dipole parity is always preferred and solutions with periods around 22 yr and a correct phase difference between flux emergence in low latitudes and the strength of the polar fields are found for a return flow speed around 2 m s-1, turbulent

  13. Barriers to return to work after burn injuries.

    Science.gov (United States)

    Esselman, Peter C; Askay, Shelley Wiechman; Carrougher, Gretchen J; Lezotte, Dennis C; Holavanahalli, Radha K; Magyar-Russell, Gina; Fauerbach, James A; Engrav, Loren H

    2007-12-01

    To identify barriers to return to work after burn injury as identified by the patient. A cohort study with telephone interview up to 1 year. Hospital-based burn centers at 3 national sites. Hospitalized patients (N=154) meeting the American Burn Association criteria for major burn injury, employed at least 20 hours a week at the time of injury, and with access to a telephone after discharge. Patients were contacted via telephone every 2 weeks up to 4 months, then monthly up to 1 year after discharge. A return to work survey was used to identify barriers that prevented patients from returning to work. A graphic rating scale determined the impact of each barrier. By 1 year, 79.7% of patients returned to work. Physical and wound issues were barriers early after discharge. Although physical abilities continued to be a significant barrier up to 1 year, working conditions (temperature, humidity, safety) and psychosocial factors (nightmares, flashbacks, appearance concerns) became important issues in those with long-term disability. The majority of patients return to work after a burn injury. Although physical and work conditions are important barriers, psychosocial issues need to be evaluated and treated to optimize return to work.

  14. Return to Experience and Initial Wage Level

    DEFF Research Database (Denmark)

    Sørensen, Kenneth Lykke; Vejlin, Rune Majlund

    This paper estimates the relationship between initial wage and return to experience. We use a Mincer-like wage model to nonparametrically estimate this relationship allowing for an unobservable individual permanent effect in wages and unobservable individual return to experience. The relationship...

  15. Links Between the Deep Western Boundary Current, Labrador Sea Water Formation and Export, and the Meridional Overturning Circulation

    Science.gov (United States)

    Myers, Paul G.; Kulan, Nilgun

    2010-05-01

    Based on an isopyncal analysis of historical data, 3-year overlapping triad fields of objectively analysed temperature and salinity are produced for the Labrador Sea, covering 1949-1999. These fields are then used to spectrally nudge an eddy-permitting ocean general circulation model of the sub-polar gyre, otherwise forced by inter annually varying surface forcing based upon the Coordinated Ocean Reference Experiment (CORE). High frequency output from the reanalysis is used to examine Labrador Sea Water formation and its export. A number of different apprpoaches are used to estimate Labrador Sea Water formation, including an instanteous kinematic approach to calculate the annual rate of water mass subduction at a given density range. Historical transports are computed along sections at 53 and 56N for several different water masses for comparison with recent observations, showing a decline in the stength of the deep western boundary current with time. The variability of the strength of the meridional overturning circulation (MOC) from the reanalysis is also examined in both depth and density space. Linkages between MOC variability and water mass formation variability is considered.

  16. Cold-season atmospheric response to the natural variability of the Atlantic meridional overturning circulation

    Energy Technology Data Exchange (ETDEWEB)

    Gastineau, Guillaume; Frankignoul, Claude [LOCEAN/IPSL, Universite Pierre et Marie Curie, 4 place Jussieu, BP100, Paris Cedex 05 (France)

    2012-07-15

    The influence of the natural variability of the Atlantic meridional overturning circulation (AMOC) on the atmosphere is studied in multi-centennial simulations of six global climate models, using Maximum Covariance Analysis (MCA). In all models, a significant but weak influence of the AMOC changes is found during the Northern Hemisphere cold-season, when the ocean leads the atmosphere by a few years. Although the oceanic pattern slightly varies, an intensification of the AMOC is followed in all models by a weak sea level pressure response that resembles a negative phase of the North Atlantic Oscillation (NAO). The signal amplitude is typically 0.5 hPa and explains about 10% of the yearly variability of the NAO in all models. The atmospheric response seems to be due primarily due to an increase of the heat loss along the North Atlantic Current and the subpolar gyre, associated with an AMOC-driven warming. Sea-ice changes appear to be less important. The stronger heating is associated to a southward shift of the lower-tropospheric baroclinicity and a decrease of the eddy activity in the North Atlantic storm track, which is consistent with the equivalent barotropic perturbation resembling the negative phase of the NAO. This study thus provides some evidence of an atmospheric signature of the AMOC in the cold-season, which may have some implications for the decadal predictability of climate in the North Atlantic region. (orig.)

  17. Expert judgements on the response of the Atlantic meridional overturning circulation to climate change

    International Nuclear Information System (INIS)

    Zickfeld, K.; Levermann, A.; Kuhlbrodt, T.; Rahmstorf, S.; Morgan, M.G.; Keith, D.W.

    2007-01-01

    We present results from detailed interviews with 12 leading climate scientists about the possible effects of global climate change on the Atlantic Meridional Overturning Circulation (AMOC). The elicitation sought to examine the range of opinions within the climatic research community about the physical processes that determine the current strength of the AMOC, its future evolution in a changing climate and the consequences of potential AMOC changes. Experts assign different relative importance to physical processes which determine the present-day strength of the AMOC as well as to forcing factors which determine its future evolution under climate change. Many processes and factors deemed important are assessed as poorly known and insufficiently represented in state-of-the-art climate models. All experts anticipate a weakening of the AMOC under scenarios of increase of greenhouse gas concentrations. Two experts expect a permanent collapse of the AMOC as the most likely response under a 4xCO2 scenario. Assuming a global mean temperature increase in the year 2100 of 4 K, eight experts assess the probability of triggering an AMOC collapse as significantly different from zero, three of them as larger than 40%. Elicited consequences of AMOC reduction include strong changes in temperature, precipitation distribution and sea level in the North Atlantic area. It is expected that an appropriately designed research program, with emphasis on long-term observations and coupled climate modeling, would contribute to substantially reduce uncertainty about the future evolution of the AMOC

  18. MAPEAMENTO DE UNIDADES DE RELEVO NA MÉDIA SERRA DO ESPINHAÇO MERIDIONAL - MG

    Directory of Open Access Journals (Sweden)

    Éric Andrade Rezende

    2011-04-01

    Full Text Available O presente trabalho propõe um mapeamento de unidades de relevo para a porção sul do terço médio da Serra do Espinhaço Meridional. As unidades de relevo foram delimitadas a partir da análise integrada de cartas temáticas e imagens de satélite que permitiram observar variações na morfologia, na altimetria, na declividade, na litoestrutura e na organização da rede de drenagem. A etapa de cartografia digital, processada no software ArcGis 9.2, se baseou na utilização de produtos SRTM (Shuttle Radar Topography Mission. Os procedimentos metodológicos também incluíram trabalhos de campo e pesquisa bibliográfica. Foi empregada a taxonomia do mapeamento geomorfológico proposta pelo IBGE (2009, através da qual foram individualizadas quatorze Unidades Geomorfológicas. As unidades estão distribuídas entre cinco diferentes compartimentos do seguinte modo: dois planaltos, duas escarpas, seis depressões, três conjuntos de cristas e um conjunto de patamares. Foi possível observar que a disposição geral das unidades reflete o forte controle litoestrutural imposto ao relevo regional. Destaca-se a resistência diferenciada das diversas litologias frente aos processos denudacionais e a influência da neotectônica na geomorfogênese.

  19. The analysis of SCS return momentum effects on the RCS water level during mid-loop operations

    Energy Technology Data Exchange (ETDEWEB)

    swang Seo, J.; Young Yang, J.; Tack Hwang, S. [Seoul National Univ. (Korea, Republic of)

    1995-09-01

    An accurate prediction of Reactor Coolant System (RCS) water levels is of importance in the determination of allowable operating range to ensure the safety during the mid-loop operations. However, complex hydraulic phenomena induced by Shutdown Cooling System (SCS) return momentum cause different water levels from those in the loop where the water level indicators are located. This was apparantly observed at the pre-core cold hydro test of the Younggwang Nuclear Unit 3 (YGN 3) in Korea. In this study, in order to analytically understand the effect of the SCS return momentum on the RCS water level and its general trend, a model using one-dimensional momentum equation, hydraulic jump, Bernoulli equation, flow resistance coefficient, and total water volume conservation has been developed to predict the RCS water levels at various RCS locations during the mid-loop conditions and the simulation results were compared with the test data. The analysis shows that the hydraulic jump in the operating cold legs in conjunction with the momentum loss throughout the RCS is the main cause creating the water level differences at various RCS locations. The prediction results provide good explanations for the test data and show the significant effect of the SCS return momentum on the RCS water levels.

  20. The analysis of SCS return momentum effects on the RCS water level during mid-loop operations

    International Nuclear Information System (INIS)

    swang Seo, J.; Young Yang, J.; Tack Hwang, S.

    1995-01-01

    An accurate prediction of Reactor Coolant System (RCS) water levels is of importance in the determination of allowable operating range to ensure the safety during the mid-loop operations. However, complex hydraulic phenomena induced by Shutdown Cooling System (SCS) return momentum cause different water levels from those in the loop where the water level indicators are located. This was apparantly observed at the pre-core cold hydro test of the Younggwang Nuclear Unit 3 (YGN 3) in Korea. In this study, in order to analytically understand the effect of the SCS return momentum on the RCS water level and its general trend, a model using one-dimensional momentum equation, hydraulic jump, Bernoulli equation, flow resistance coefficient, and total water volume conservation has been developed to predict the RCS water levels at various RCS locations during the mid-loop conditions and the simulation results were compared with the test data. The analysis shows that the hydraulic jump in the operating cold legs in conjunction with the momentum loss throughout the RCS is the main cause creating the water level differences at various RCS locations. The prediction results provide good explanations for the test data and show the significant effect of the SCS return momentum on the RCS water levels

  1. Intergranular attack evaluation from hideout return

    International Nuclear Information System (INIS)

    Nordmann, F.; Dupin, M.; Menet, O.; Fiquet, J.-M.

    1989-01-01

    Intergranular Attack (IGA) is the secondary side corrosion mechanism on PWR steam generator tubing, which can occur most frequently even with a good waterchemistry. It has moderately developed in a few French units. Consequently, several remedies have been implemented, such as sodium content decrease in makeup water and application of more stringent chemistry specifications. In order to evaluate the local chemistry in restricted areas where IGA may occur, a large hideout return programme has been carried out on many units. It shows that free alkalinity returning during shutdown is usually ranging from 0.5 to 5 g of sodium per steam generator, and that the required time to let it return is about 40 hours. However, high temperature pH calculations indicate that such an amount of alkalinity can correspond to a potentially corrosive solution in restricted areas, where a concentration factor of 10 5 to 10 7 can be reached, inducing a pH of 10 at 300 o C. Studies are still in progress in order to define when a shutdown should be required to allow hideout return and help to prevent IGA. (author)

  2. Nurses' views about returning to practice after a career break.

    Science.gov (United States)

    Durand, Mary Alison; Randhawa, Gurch

    Shortages in nursing staff have led to recruitment campaigns targeting nurses who have left the profession. The present study explored reasons why career-break nurses decide for or against a return to practice, as well as perceptions of nursing following return. Semistructured interview were conducted with 24 nurses who had returned recently to the profession and 28 nurses on a "career break". Findings revealed that those who returned did so when their personal circumstances allowed, and half returned as bank nurses in order to work flexible, family-friendly hours. Some non-returners reported that they could not afford to return because of childcare costs. Although still a caring one, the nurse's role is seen by returners as becoming increasingly technologically and administratively demanding. Flexibility with regard to working practices, increased salaries and demonstrating that it values its staff, were highlighted by interviewees generally as priority issues for the NHS if it wishes to recruit career-break nurses.

  3. Return to experience and initial wage level

    DEFF Research Database (Denmark)

    Sørensen, K.L.; Vejlin, R.

    2014-01-01

    This paper estimates the relationship between initial wage and return to experience. We use a Mincer-like wage model to non-parametrically estimate this relationship allowing for an unobservable individual permanent effect in wages and unobservable individual return to experience. The relationshi...

  4. Legal institutions, strategic default, and stock returns

    NARCIS (Netherlands)

    Favara, G.; Schroth, E.; Valta, P.

    2008-01-01

    This paper studies the impact of legal institutions on stock returns. More specifically, we examine how differences in debt enforcement and creditor protection around the world affect stock returns of individual firms. We hypothesize that if legal institutions prevent shareholders from engaging in

  5. Husbands' return migration and wives' occupational choices

    NARCIS (Netherlands)

    Mahe, Clotilde

    2017-01-01

    Exploiting the documented effect of migration on occupational choice upon return to their origin country with data from Egypt, we establish a link between return migration of men and their wives' time use through within-couple occupational interdependence. Seemingly Unrelated Regression model

  6. Risk-return relationship in a complex adaptive system.

    Directory of Open Access Journals (Sweden)

    Kunyu Song

    Full Text Available For survival and development, autonomous agents in complex adaptive systems involving the human society must compete against or collaborate with others for sharing limited resources or wealth, by using different methods. One method is to invest, in order to obtain payoffs with risk. It is a common belief that investments with a positive risk-return relationship (namely, high risk high return and vice versa are dominant over those with a negative risk-return relationship (i.e., high risk low return and vice versa in the human society; the belief has a notable impact on daily investing activities of investors. Here we investigate the risk-return relationship in a model complex adaptive system, in order to study the effect of both market efficiency and closeness that exist in the human society and play an important role in helping to establish traditional finance/economics theories. We conduct a series of computer-aided human experiments, and also perform agent-based simulations and theoretical analysis to confirm the experimental observations and reveal the underlying mechanism. We report that investments with a negative risk-return relationship have dominance over those with a positive risk-return relationship instead in such a complex adaptive systems. We formulate the dynamical process for the system's evolution, which helps to discover the different role of identical and heterogeneous preferences. This work might be valuable not only to complexity science, but also to finance and economics, to management and social science, and to physics.

  7. Risk-return relationship in a complex adaptive system.

    Science.gov (United States)

    Song, Kunyu; An, Kenan; Yang, Guang; Huang, Jiping

    2012-01-01

    For survival and development, autonomous agents in complex adaptive systems involving the human society must compete against or collaborate with others for sharing limited resources or wealth, by using different methods. One method is to invest, in order to obtain payoffs with risk. It is a common belief that investments with a positive risk-return relationship (namely, high risk high return and vice versa) are dominant over those with a negative risk-return relationship (i.e., high risk low return and vice versa) in the human society; the belief has a notable impact on daily investing activities of investors. Here we investigate the risk-return relationship in a model complex adaptive system, in order to study the effect of both market efficiency and closeness that exist in the human society and play an important role in helping to establish traditional finance/economics theories. We conduct a series of computer-aided human experiments, and also perform agent-based simulations and theoretical analysis to confirm the experimental observations and reveal the underlying mechanism. We report that investments with a negative risk-return relationship have dominance over those with a positive risk-return relationship instead in such a complex adaptive systems. We formulate the dynamical process for the system's evolution, which helps to discover the different role of identical and heterogeneous preferences. This work might be valuable not only to complexity science, but also to finance and economics, to management and social science, and to physics.

  8. Expected commodity returns and pricing models

    International Nuclear Information System (INIS)

    Cortazar, Gonzalo; Kovacevic, Ivo; Schwartz, Eduardo S.

    2015-01-01

    Stochastic models of commodity prices have evolved considerably in terms of their structure and the number and interpretation of the state variables that model the underlying risk. Using multiple factors, different specifications and modern estimation techniques, these models have gained wide acceptance because of their success in accurately fitting the observed commodity futures' term structures and their dynamics. It is not well emphasized however that these models, in addition to providing the risk neutral distribution of future spot prices, also provide their true distribution. While the parameters of the risk neutral distribution are estimated more precisely and are usually statistically significant, some of the parameters of the true distribution are typically measured with large errors and are statistically insignificant. In this paper we argue that to increase the reliability of commodity pricing models, and therefore their use by practitioners, some of their parameters — in particular the risk premium parameters — should be obtained from other sources and we show that this can be done without losing any precision in the pricing of futures contracts. We show how the risk premium parameters can be obtained from estimations of expected futures returns and provide alternative procedures for estimating these expected futures returns. - Highlights: • Simple methodology to improve the performance of commodity pricing models • New information about commodity futures expected return is added to the estimation. • No significant effect in pricing futures contracts is observed. • More reliable commodity pricing model's expected returns are obtained. • Methodology is open to any expected futures return model preferred by practitioner

  9. Lidar 2009 - All Returns

    Data.gov (United States)

    Kansas Data Access and Support Center — LIDAR-derived binary (.las) files containing classified points of all returns. We have 3 classifications Unclassified, Ground, Low points. The average Ground Sample...

  10. Returns on Investment in California County Departments of Public Health

    Science.gov (United States)

    2016-01-01

    Objectives. To estimate the average return on investment for the overall activities of county departments of public health in California. Methods. I gathered the elements necessary to estimate the average return on investment for county departments of public health in California during the period 2001 to 2008–2009. These came from peer-reviewed journal articles published as part of a larger project to develop a method for determining return on investment for public health by using a health economics framework. I combined these elements by using the standard formula for computing return on investment, and performed a sensitivity analysis. Then I compared the return on investment for county departments of public health with the returns on investment generated for various aspects of medical care. Results. The estimated return on investment from $1 invested in county departments of public health in California ranges from $67.07 to $88.21. Conclusions. The very large estimated return on investment for California county departments of public health relative to the return on investment for selected aspects of medical care suggests that public health is a wise investment. PMID:27310339

  11. Exploring consumer online product returning behavior : Chinese e-consumers’ perspective

    OpenAIRE

    Zhu, Yijun

    2018-01-01

    In the retail world, product returns are a common practice by consumers. Many businesses have been attempting to obtain more sales by providing customers with lenient return policies as well as customer-friendly return processes and procedures. Over the past decade, the issue of product returns by consumers is on the rise and drawing increased attention from practitioners and researchers. The objective of this thesis is to explore Chinese e-consumers’ perception of fraudulent returning beh...

  12. Analyse Risk-Return Paradox: Evidence from Electricity Sector of Pakistan

    OpenAIRE

    Naqi Shah, Sadia; Qayyum, Abdul

    2016-01-01

    This study analyse risk return relationship of the electricity companies of Pakistan by using the log return series of these electricity companies. Financial time series data have the property of autoregressive heteroscedasticity so move towards the GARCH family test. As the study want to analyse the risk return relationship so, GARCH-M Model of Engel et al (1987) is used, who empirically found relationship between risk and return. Results show that risk return in case of Pakistan electricity...

  13. Returns management in the supply chain

    Directory of Open Access Journals (Sweden)

    Anna Maria Jeszka

    2014-09-01

    Full Text Available Background:  The aim of this exploratory empirical research was to evaluate the level of cooperation in the area of reverse logistics between selected retail chains and logistics operators and suppliers; to identify and evaluate the influence the procedures of handling returns have on the relationships with customers, cost reduction, value recovery, inventory reduction and increasing profitability; as well as determining to what extent logistics operators are involved in the procedures of handling returns in the analysed chains. Methods: Based on the literature and the experience of researchers from developed countries a questionnaire was constructed which was subsequently used to conduct empirical research in selected retail chains operating in two provinces in Poland. The questionnaire survey involved the sales personnel of selected retail chains in the clothing industry. Overall, 105 questionnaires were collected and analysed. Results: Various aspects of cooperation with suppliers and logistics operators in respect of handling returns were evaluated. Most indicators of cooperation were evaluated favourably, with the exception of joint access to the database, the use of inventory data available online, and access to information from the warehouse, which received low marks from the respondents. In the case of the studied stores, some of the activities in the area of reverse logistics are outsourced; for example, obtaining products from users, logistics, and the transport of returns are typically done by an outside operator. Inspection, sorting, appraisal, repairs, as well as the sales of refurbished products are usually performed within the studied retail corporations. Conclusions: The research has shown that the retail chains developed very good programmes for handling returns in the supply chain, as evidenced by the presented and highly rated indicators of cooperation, with the exception of information exchange where there is still much

  14. Analytical study of electron flows with a virtual cathode

    International Nuclear Information System (INIS)

    Dubinov, A.E.

    2000-01-01

    The dynamics of the electron flow behavior by its injection into a half-space is considered. Two problems are considered, namely the long-term injection of a monoenergetic electron flow and instantaneous flow injection with an assigned electron energy spectrum. The all flow electrons in both cases return to the injection plane. The simple analytical self-consistent model of the initial stage of the virtual cathode formation in a plane-parallel equipotential gap is plotted in the course of analysis whereof the duration of the virtual cathode formation process is determined. The performance of this model is not limited by the multivalence of the electron velocity in the flow. This makes it possible to extend the frames of the model performance relative to the moment of the virtual cathode formation and to consider its dynamics. The frequency of electron oscillations in the potential cathode-virtual cathode well is determined on the basis of the above model [ru

  15. Return to the workforce following infective endocarditis

    DEFF Research Database (Denmark)

    Butt, Jawad H.; Kragholm, Kristian; Dalager-Pedersen, Michael

    2018-01-01

    Background The ability to return to work after infective endocarditis (IE) holds important socioeconomic consequences for both patients and society, yet data on this issue are sparse. We examined return to the workforce and associated factors in IE patients of working age. Methods Using Danish...

  16. Return Predictability, Model Uncertainty, and Robust Investment

    DEFF Research Database (Denmark)

    Lukas, Manuel

    Stock return predictability is subject to great uncertainty. In this paper we use the model confidence set approach to quantify uncertainty about expected utility from investment, accounting for potential return predictability. For monthly US data and six representative return prediction models, we...... find that confidence sets are very wide, change significantly with the predictor variables, and frequently include expected utilities for which the investor prefers not to invest. The latter motivates a robust investment strategy maximizing the minimal element of the confidence set. The robust investor...... allocates a much lower share of wealth to stocks compared to a standard investor....

  17. 26 CFR 1.6031(a)-1 - Return of partnership income.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 13 2010-04-01 2010-04-01 false Return of partnership income. 1.6031(a)-1...) INCOME TAX (CONTINUED) INCOME TAXES Information Returns § 1.6031(a)-1 Return of partnership income. (a) Domestic partnerships—(1) Return required. Except as provided in paragraphs (a)(3) and (c) of this section...

  18. Tick size and stock returns

    Science.gov (United States)

    Onnela, Jukka-Pekka; Töyli, Juuso; Kaski, Kimmo

    2009-02-01

    Tick size is an important aspect of the micro-structural level organization of financial markets. It is the smallest institutionally allowed price increment, has a direct bearing on the bid-ask spread, influences the strategy of trading order placement in electronic markets, affects the price formation mechanism, and appears to be related to the long-term memory of volatility clustering. In this paper we investigate the impact of tick size on stock returns. We start with a simple simulation to demonstrate how continuous returns become distorted after confining the price to a discrete grid governed by the tick size. We then move on to a novel experimental set-up that combines decimalization pilot programs and cross-listed stocks in New York and Toronto. This allows us to observe a set of stocks traded simultaneously under two different ticks while holding all security-specific characteristics fixed. We then study the normality of the return distributions and carry out fits to the chosen distribution models. Our empirical findings are somewhat mixed and in some cases appear to challenge the simulation results.

  19. High Resolution Monitoring of River Bluff Erosion Reveals Failure Mechanisms and Geomorphically Effective Flows

    Directory of Open Access Journals (Sweden)

    Sara Ann Kelly

    2018-03-01

    Full Text Available Using a combination of Structure from Motion and time lapse photogrammetry, we document rapid river bluff erosion occurring in the Greater Blue Earth River (GBER basin, a muddy tributary to the sediment-impaired Minnesota River in south central Minnesota. Our datasets elucidated dominant bluff failure mechanisms and rates of bluff retreat in a transient system responding to ongoing streamflow increases and glacial legacy impacts. Specifically, we document the importance of fluvial scour, freeze–thaw, as well as other drivers of bluff erosion. We find that even small flows, a mere 30% of the two-year recurrence interval flow, are capable of causing bluff erosion. During our study period (2014–2017, the most erosion was associated with two large flood events with 13- and 25-year return periods. However, based on the frequency of floods and magnitude of bluff face erosion associated with floods over the last 78 years, the 1.2-year return interval flood has likely accomplished the most cumulative erosion, and is thus more geomorphically effective than larger magnitude floods. Flows in the GBER basin are nonstationary, increasing across the full range of return intervals. We find that management implications differ considerably depending on whether the bluff erosion-runoff power law exponent, γ, is greater than, equal to, or less than 1. Previous research has recommended installation of water retention sites in tributaries to the Minnesota River in order to reduce flows and sediment loading from river bluffs. Our findings support the notion that water retention would be an effective practice to reduce sediment loading and highlight the importance of managing for both runoff frequency and magnitude.

  20. Recovery of testicular blood flow following ligation of testicular vessels

    International Nuclear Information System (INIS)

    Pascual, J.A.; Villanueva-Meyer, J.; Salido, E.; Ehrlich, R.M.; Mena, I.; Rajfer, J.

    1989-01-01

    To determine whether initial ligation of the testicular vessels of the high undescended testis followed by a delayed secondary orchiopexy is a viable alternative to the classical Fowler-Stephens procedure, a series of preliminary experiments were conducted in the rat in which testicular blood flow was measured by the 133-xenon washout technique before, and 1 hour and 30 days after ligation of the vessels. In addition, testicular histology, and testis and sex-accessory tissue weights were measured in 6 control, 6 sham operated and 6 testicular vessel ligated rats 54 days after vessel ligation. The data demonstrate that ligation and division of the testicular blood vessels produce an 80 per cent decrease in testicular blood flow 1 hour after ligation of the vessels. However, 30 days later testis blood flow returns to the control and pre-treatment value. There were no significant changes in testis or sex-accessory tissue weights 54 days after vessel ligation. Histologically, 4 of the surgically operated testes demonstrated necrosis of less than 25 per cent of the seminiferous tubules while 1 testis demonstrated more than 75 per cent necrosis. The rest of the tubules in all 6 testes demonstrated normal spermatogenesis. From this study we conclude that initial testicular vessel ligation produces an immediate decrease in testicular blood flow but with time the collateral vessels are able to compensate and return the testis blood flow to its normal pre-treatment value. These preliminary observations lend support for the concept that initial ligation of the testicular vessels followed by a delayed secondary orchiopexy in patients with a high undescended testis may be a possible alternative to the classical Fowler-Stephens approach

  1. DESIGNING THE RETURN MIGRATION OF ROMANIAN STUDENTS

    Directory of Open Access Journals (Sweden)

    Magdalena VELCIU

    2017-05-01

    Full Text Available Romanian youth migration is an increasing phenomenon, due to subjective and objective factors as economical reasons, professional carrer and increasingly more international competition for talent. In these circumstances, the present article aims to evaluate determinant factors that contribute to the decision of Romanian graduates to return national labour market. We sustain that young Romanians consider carefully and hardly decide their professional future. A particular attention is given to their personal reasons and motivations as well as family and friends network. For designing returning factors we present the results of a questionnaire survey, asking young pupils and students about their future educational way and personal reasons underlying the decision to study in a foreign country and taking into consideration the returning decision. As far international student migration is seen as a first step to migration for work, our work desires to fight for returning home of Romanian well-educated graduates.

  2. Fluctuation behaviors of financial return volatility duration

    Science.gov (United States)

    Niu, Hongli; Wang, Jun; Lu, Yunfan

    2016-04-01

    It is of significantly crucial to understand the return volatility of financial markets because it helps to quantify the investment risk, optimize the portfolio, and provide a key input of option pricing models. The characteristics of isolated high volatility events above certain threshold in price fluctuations and the distributions of return intervals between these events arouse great interest in financial research. In the present work, we introduce a new concept of daily return volatility duration, which is defined as the shortest passage time when the future volatility intensity is above or below the current volatility intensity (without predefining a threshold). The statistical properties of the daily return volatility durations for seven representative stock indices from the world financial markets are investigated. Some useful and interesting empirical results of these volatility duration series about the probability distributions, memory effects and multifractal properties are obtained. These results also show that the proposed stock volatility series analysis is a meaningful and beneficial trial.

  3. Return to play in elite rugby union: application of global positioning system technology in return-to-running programs.

    Science.gov (United States)

    Reid, Laura C; Cowman, Jason R; Green, Brian S; Coughlan, Garrett F

    2013-05-01

    Global positioning systems (GPS) are widely used in sport settings to evaluate the physical demands on players in training and competition. The use of these systems in the design and implementation of rehabilitation and return-to-running programs has not yet been elucidated. To demonstrate the application of GPS technology in the management of return to play in elite-club Rugby Union. Case series. Professional Rugby Union club team. 8 elite Rugby Union players (age 27.86 ± 4.78 y, height 1.85 ± 0.08 m, weight 99.14 ± 9.96 kg). Players wore GPS devices for the entire duration of a club game. Variables of locomotion speed and distance were measured. Differences in physical demands between playing positions were observed for all variables. An analysis of the position-specific physical demands measured by GPS provides key information regarding the level and volume of loads sustained by a player in a game environment. Using this information, sports-medicine practitioners can develop rehabilitation and return-to-running protocols specific to the player position to optimize safe return to play.

  4. Risk-Return Trade-Off for European Stock Markets

    OpenAIRE

    Aslanidis, Nektarios; Christiansen, Charlotte; Savva, Christos S.

    2015-01-01

    This paper adopts dynamic factor models with macro-finance predictors to revisit the intertemporal risk-return relation in five large European stock markets. We identify country specific, Euro area, and global factors to determine the conditional moments of returns considering the role of higher-order moments as additional measures of risk. The preferred combination of factors varies across countries. In the linear model, there is a strong but negative relation between conditional returns and...

  5. Understanding the Puzzling Risk-Return Relationship for Housing

    OpenAIRE

    Lu Han

    2013-01-01

    Standard theory predicts a positive relationship between risk and return, yet recent data show that housing returns vary positively with risk in some markets but negatively in others. This paper rationalizes these cross-market differences in the risk-return relationship for housing, and in so doing, explains the puzzling negative relationship. The paper shows that when the current house provides a hedge against the risk associated with the future housing consumption, households are willing to...

  6. Meteorological analysis of the eruption of soufriere in april 1979.

    Science.gov (United States)

    Barr, S; Heffter, J L

    1982-06-04

    Meteorological upper-air data, in conjunction with satellite imagery, lidar light detection and ranging returns, and aircraft sampling, aid in the determination of plume altitude and transport. The estimated trajectories indicate that the ash was transported eastward across the Atlantic to Africa in 3 to 5 days and that there was modest meridional transport as far as 15 degrees poleward during the first week of travel.

  7. 26 CFR 301.6063-1 - Signing of partnership returns.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Signing of partnership returns. 301.6063-1 Section 301.6063-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED....6063-1 Signing of partnership returns. For provisions relating to the signing of returns of partnership...

  8. Comet coma sample return instrument

    Science.gov (United States)

    Albee, A. L.; Brownlee, Don E.; Burnett, Donald S.; Tsou, Peter; Uesugi, K. T.

    1994-01-01

    The sample collection technology and instrument concept for the Sample of Comet Coma Earth Return Mission (SOCCER) are described. The scientific goals of this Flyby Sample Return are to return to coma dust and volatile samples from a known comet source, which will permit accurate elemental and isotopic measurements for thousands of individual solid particles and volatiles, detailed analysis of the dust structure, morphology, and mineralogy of the intact samples, and identification of the biogenic elements or compounds in the solid and volatile samples. Having these intact samples, morphologic, petrographic, and phase structural features can be determined. Information on dust particle size, shape, and density can be ascertained by analyzing penetration holes and tracks in the capture medium. Time and spatial data of dust capture will provide understanding of the flux dynamics of the coma and the jets. Additional information will include the identification of cosmic ray tracks in the cometary grains, which can provide a particle's process history and perhaps even the age of the comet. The measurements will be made with the same equipment used for studying micrometeorites for decades past; hence, the results can be directly compared without extrapolation or modification. The data will provide a powerful and direct technique for comparing the cometary samples with all known types of meteorites and interplanetary dust. This sample collection system will provide the first sample return from a specifically identified primitive body and will allow, for the first time, a direct method of matching meteoritic materials captured on Earth with known parent bodies.

  9. FTRANS, Radionuclide Flow in Groundwater and Fractured Rock

    International Nuclear Information System (INIS)

    Huyakorn, P.; Golis, M.J.

    1987-01-01

    1 - Description of program or function: FTRANS (Fractured flow and Transport of Radionuclides) is a two-dimensional finite-element code designed to simulate ground-water flow and transport of radioactive nuclides in a fractured porous return medium. FTRANS takes into account fluid interactions between the fractures and porous matrix blocks, advective-dispersive transport in the fractures and diffusion in the porous matrix blocks, and chain reactions of radionuclide components. It has the capability to model the fractured system using either the dual-porosity or the discrete- fracture modeling approach or a combination of both. FTRANS can be used to perform two-dimensional near-field or far-field predictive analyses of ground-water flow and to perform risk assessments of radionuclide transport from nuclear waste repository subsystems to the biosphere. 2 - Restrictions on the complexity of the problem: Although FTRANS does cannot account for deformation processes which can affect the flow capacity and velocity field

  10. ADVERTISING ON FACEBOOK: THE EFFECT ON FUND FLOWS OF FUND FAMILY

    OpenAIRE

    Kang, Jiaqi

    2017-01-01

    Using data for the top 100 US mutual fund families for the period between Jan 2009 to Jun 2016, this paper studies the relationship between mutual fund families’ advertising on Facebook and their fund flow. In particular, I examine whether advertising via social media helps mutual funds to attract new fund flow. I also include the number of followers to proxy for visibility and past returns to control for performance. In line with previous research, I find that large part of the variation in ...

  11. Investment Strategy Based on Aviation Accidents: Are there abnormal returns?

    Directory of Open Access Journals (Sweden)

    Marcos Rosa Costa

    2013-06-01

    Full Text Available This article investigates whether an investment strategy based on aviation accidents can generate abnormal returns. We performed an event study considering all the aviation accidents with more than 10 fatalities in the period from 1998 to 2009 and the stock market performance of the respective airlines and aircraft manufacturers in the days after the event. The tests performed were based on the model of Campbell, Lo & MacKinlay (1997 for definition of abnormal returns, by means of linear regression between the firms’ stock returns and the return of a market portfolio used as a benchmark. This enabled projecting the expected future returns of the airlines and aircraft makers, for comparison with the observed returns after each event. The result obtained suggests that an investment strategy based on aviation accidents is feasible because abnormal returns can be obtained in the period immediately following an aviation disaster.

  12. Aggregate Unemployment Decreases Individual Returns to Education

    Science.gov (United States)

    Ammermueller, Andreas; Kuckulenz, Anja; Zwick, Thomas

    2009-01-01

    Aggregate unemployment may affect individual returns to education through qualification-specific responses in participation and wage bargaining. This paper shows that an increase in regional unemployment by 1% decreases returns to education by 0.005 percentage points. This implies that higher skilled employees are better sheltered from labour…

  13. Returnable containers: an example of reverse logistics

    NARCIS (Netherlands)

    L.G. Kroon (Leo); G.M.C. Vrijens

    1996-01-01

    textabstractConsiders the application of returnable containers as an example of reverse logistics. A returnable container is a type of secondary packaging that can be used several times in the same form, in contrast with traditional cardboard boxes. For this equipment to be used, a system for the

  14. Sovereign Risk and Currently Returns

    DEFF Research Database (Denmark)

    Della Corte, Pasquale; Sarno, Lucio; Schmeling, Maik

    We empirically investigate the relation between sovereign risk and exchange rates for a broad set of currencies. An increase in the credit default swap (CDS) spread of a country is accompanied by a significant depreciation of the exchange rate. More generally, CDS spread changes have substantial...... explanatory power for currency returns which is largely driven by shocks to global credit risk. Consistent with the notion that sovereign risk is priced, we find that a country's exposure to global credit risk forecasts excess returns to trading exchange rates as well as to trading on the volatility, skewness...

  15. Sovereign Risk and Currency Returns

    DEFF Research Database (Denmark)

    Della Corte, Pasquale; Sarno, Lucio; Schmeling, Maik

    We empirically investigate the relation between sovereign risk and exchange rates for a broad set of currencies. An increase in the credit default swap (CDS) spread of a country is accompanied by a significant depreciation of the exchange rate. More generally, CDS spread changes have substantial...... explanatory power for currency returns which is largely driven by shocks to global credit risk. Consistent with the notion that sovereign risk is priced, we find that a country's exposure to global credit risk forecasts excess returns to trading exchange rates as well as to trading on the volatility, skewness...

  16. Estudios sobre la vegetación del estado de Paraná (Brasil meridional

    Directory of Open Access Journals (Sweden)

    de Bolòs, Oriol

    1991-12-01

    Full Text Available Contribution to knowledge about the vegetation of the state of Paraná in southern Brazil (Serra do Mar, Planaltos, Iguaçu Valley. Numerous plant associations are described and grouped together in the following classes: Pistio-Eichhornietea (communities of floating cormophytes Xyrido-Typhetea (helophytic herbaceous vegetation Polypodio-Tillandsietea (epiphytic and comophytic vegetation Ruderali-Manihotetea (ruderal and segetal vegetation Andropogono-Baccharidetea (savanoid vegetation Rhizophoretea (mangroves Lantano-Chusqueetea (woody marginal communities of the forest Cedrelo-Ocoteetea (rain and mesophilous forest. Special attention is paid to the study of the physiognomy, structure and dynamism of the vegetation and its biogeographical significance.

    Aportación al conocimiento de la vegetación del estado de Paraná en el Brasil meridional (Serra do Mar, Planaltos, valle del Iguaçu. Se describen numerosas asociaciones vegetales agrupadas en las clases siguientes: Pistio-Eichhornietea (comunidades de cormófitos flotantes. Xyrido-Typhetea (vegetación herbácea helofítica. Polypodio-Tillandsietea (vegetación epifítica y comofítica. Ruderali-Manihotetea (vegetación ruderal, viaria y arvense. Andropogono-Baccharidetea (vegetación sabanoide. Rhizophoretea (manglar. Lantano-Chusqueetea (manto marginal leñoso de la selva. Cedrelo-Ocoteetea (selva pluvial y mesófila. Se dedica atención especial al estudio de la fisionomía, estructura y dinamismo de la vegetación y a su significación biogeográfica.

  17. Return to golf after spine surgery.

    Science.gov (United States)

    Abla, Adib A; Maroon, Joseph C; Lochhead, Richard; Sonntag, Volker K H; Maroon, Adara; Field, Melvin

    2011-01-01

    no published evidence indicates when patients can resume golfing after spine surgery. The objective of this study is to provide data from surveys sent to spine surgeons. a survey of North American Spine Society members was undertaken querying the suggested timing of return to golf. Of 1000 spine surgeons surveyed, 523 responded (52.3%). The timing of recommended return to golf and the reasons were questioned for college/professional athletes and avid and recreational golfers of both sexes. Responses were tallied for lumbar laminectomy, lumbar microdiscectomy, lumbar fusion, and anterior cervical discectomy with fusion. the most common recommended time for return to golf was 4-8 weeks after lumbar laminectomy and lumbar microdiscectomy, 2-3 months after anterior cervical fusion, and 6 months after lumbar fusion. The results showed a statistically significant increase in the recommended time to resume golf after lumbar fusion than after cervical fusion in all patients (p golf after spine surgery depends on many variables, including the general well-being of patients in terms of pain control and comfort when golfing. This survey serves as a guide that can assist medical practitioners in telling patients the average times recommended by surgeons across North America regarding return to golf after spine surgery.

  18. Efficient Return Algorithms For Associated Plasticity With Multiple Yield Planes

    DEFF Research Database (Denmark)

    Clausen, Johan Christian; Damkilde, Lars; Andersen, Lars

    2006-01-01

    of such criteria. The return formulae are in closed form and no iteration is required. The method accounts for three types of stress return: Return to a single yield plane, to a discontinuity line at the intersection of two yield planes and to a discontinuity point at the intersection between three or more yield...... planes. The infinitesimal and the consistent elastoplastic constitutive matrix are calculated for each type of stress return, as are the conditions to ascertain which type of return is required. The method is exemplified with the Mohr-Coulomb yield criterion....

  19. What stock market returns to expect for the future?

    Science.gov (United States)

    Diamond, P A

    2000-01-01

    In evaluating proposals for reforming Social Security that involve stock investments, the Office of the Chief Actuary (OCACT) has generally used a 7.0 percent real return for stocks. The 1994-96 Advisory Council specified that OCACT should use that return in making its 75-year projections of investment-based reform proposals. The assumed ultimate real return on Treasury bonds of 3.0 percent implies a long-run equity premium of 4.0 percent. There are two equity-premium concepts: the realized equity premium, which is measured by the actual rates of return; and the required equity premium, which investors expect to receive for being willing to hold available stocks and bonds. Over the past two centuries, the realized premium was 3.5 percent on average, but 5.2 percent for 1926 to 1998. Some critics argue that the 7.0 percent projected stock returns are too high. They base their arguments on recent developments in the capital market, the current high value of the stock market, and the expectation of slower economic growth. Increased use of mutual funds and the decline in their costs suggest a lower required premium, as does the rising fraction of the American public investing in stocks. The size of the decrease is limited, however, because the largest cost savings do not apply to the very wealthy and to large institutional investors, who hold a much larger share of the stock market's total value than do new investors. These trends suggest a lower equity premium for projections than the 5.2 percent of the past 75 years. Also, a declining required premium is likely to imply a temporary increase in the realized premium because a rising willingness to hold stocks tends to increase their price. Therefore, it would be a mistake during a transition period to extrapolate what may be a temporarily high realized return. In the standard (Solow) economic growth model, an assumption of slower long-run growth lowers the marginal product of capital if the savings rate is constant

  20. After a career break: supporting women returning to ICT

    OpenAIRE

    Herman, Clem

    2011-01-01

    This is a case study of an initiative to support women returning to ICT after a career break, which was run in the UK and Ireland between 2005 and 2011.The article starts by outlining how the UK government’s concern about women failing return to SET careers led to the setting up of a national campaign (RETURN) to address this issue. A brief overview of previous research about women’s reasons for leaving ICT employment and the difficulties and barriers they encounter in returning to work, sets...