Sample records for table fluctuation method

  1. A time series approach to inferring groundwater recharge using the water table fluctuation method

    NASA Astrophysics Data System (ADS)

    Crosbie, Russell S.; Binning, Philip; Kalma, Jetse D.

    2005-01-01

    The water table fluctuation method for determining recharge from precipitation and water table measurements was originally developed on an event basis. Here a new multievent time series approach is presented for inferring groundwater recharge from long-term water table and precipitation records. Additional new features are the incorporation of a variable specific yield based upon the soil moisture retention curve, proper accounting for the Lisse effect on the water table, and the incorporation of aquifer drainage so that recharge can be detected even if the water table does not rise. A methodology for filtering noise and non-rainfall-related water table fluctuations is also presented. The model has been applied to 2 years of field data collected in the Tomago sand beds near Newcastle, Australia. It is shown that gross recharge estimates are very sensitive to time step size and specific yield. Properly accounting for the Lisse effect is also important to determining recharge.

  2. Groundwater Evapotranspiration from Diurnal Water Table Fluctuation: a Modified White Based Method Using Drainable and Fillable Porosity

    NASA Astrophysics Data System (ADS)

    Acharya, S.; Mylavarapu, R.; Jawitz, J. W.

    2012-12-01

    In shallow unconfined aquifers, the water table usually shows a distinct diurnal fluctuation pattern corresponding to the twenty-four hour solar radiation cycle. This diurnal water table fluctuation (DWTF) signal can be used to estimate the groundwater evapotranspiration (ETg) by vegetation, a method known as the White [1932] method. Water table fluctuations in shallow phreatic aquifers is controlled by two distinct storage parameters, drainable porosity (or specific yield) and the fillable porosity. Yet, it is implicitly assumed in most studies that these two parameters are equal, unless hysteresis effect is considered. The White based method available in the literature is also based on a single drainable porosity parameter to estimate the ETg. In this study, we present a modification of the White based method to estimate ETg from DWTF using separate drainable (λd) and fillable porosity (λf) parameters. Separate analytical expressions based on successive steady state moisture profiles are used to estimate λd and λf, instead of the commonly employed hydrostatic moisture profile approach. The modified method is then applied to estimate ETg using the DWTF data observed in a field in northeast Florida and the results are compared with ET estimations from the standard Penman-Monteith equation. It is found that the modified method resulted in significantly better estimates of ETg than the previously available method that used only a single, hydrostatic-moisture-profile based λd. Furthermore, the modified method is also used to estimate ETg even during rainfall events which produced significantly better estimates of ETg as compared to the single λd parameter method.

  3. An empirical method for approximating stream baseflow time series using groundwater table fluctuations

    NASA Astrophysics Data System (ADS)

    Meshgi, Ali; Schmitter, Petra; Babovic, Vladan; Chui, Ting Fong May

    2014-11-01

    Developing reliable methods to estimate stream baseflow has been a subject of interest due to its importance in catchment response and sustainable watershed management. However, to date, in the absence of complex numerical models, baseflow is most commonly estimated using statistically derived empirical approaches that do not directly incorporate physically-meaningful information. On the other hand, Artificial Intelligence (AI) tools such as Genetic Programming (GP) offer unique capabilities to reduce the complexities of hydrological systems without losing relevant physical information. This study presents a simple-to-use empirical equation to estimate baseflow time series using GP so that minimal data is required and physical information is preserved. A groundwater numerical model was first adopted to simulate baseflow for a small semi-urban catchment (0.043 km2) located in Singapore. GP was then used to derive an empirical equation relating baseflow time series to time series of groundwater table fluctuations, which are relatively easily measured and are physically related to baseflow generation. The equation was then generalized for approximating baseflow in other catchments and validated for a larger vegetation-dominated basin located in the US (24 km2). Overall, this study used GP to propose a simple-to-use equation to predict baseflow time series based on only three parameters: minimum daily baseflow of the entire period, area of the catchment and groundwater table fluctuations. It serves as an alternative approach for baseflow estimation in un-gauged systems when only groundwater table and soil information is available, and is thus complementary to other methods that require discharge measurements.

  4. A Mathematical View of Water Table Fluctuations in a Shallow Aquifer in Brazil.

    PubMed

    Neto, Dagmar C; Chang, Hung K; van Genuchten, Martinus Th

    2016-01-01

    Detailed monitoring of the groundwater table can provide important data about both short- and long-term aquifer processes, including information useful for estimating recharge and facilitating groundwater modeling and remediation efforts. In this paper, we presents results of 4 years (2002 to 2005) of monitoring groundwater water levels in the Rio Claro Aquifer using observation wells drilled at the Rio Claro campus of São Paulo State University in Brazil. The data were used to follow natural periodic fluctuations in the water table, specifically those resulting from earth tides and seasonal recharge cycles. Statistical analyses included methods of time-series analysis using Fourier analysis, cross-correlation, and R/S analysis. Relationships could be established between rainfall and well recovery, as well as the persistence and degree of autocorrelation of the water table variations. We further used numerical solutions of the Richards equation to obtain estimates of the recharge rate and seasonable groundwater fluctuations. Seasonable soil moisture transit times through the vadose zone obtained with the numerical solution were very close to those obtained with the cross-correlation analysis. We also employed a little-used deep drainage boundary condition to obtain estimates of seasonable water table fluctuations, which were found to be consistent with observed transient groundwater levels during the period of study. © 2015, National Ground Water Association.

  5. Effect of Water-Table Fluctuations on Source Depletion and Dissolved-Plume Behavior of a Multi-Component Light Nonaqueous-Phase Liquid

    NASA Astrophysics Data System (ADS)

    Dobson, R.; Schroth, M. H.; Zeyer, J.

    2006-12-01

    Light nonaqueous-phase liquids (LNAPLs) such as gasoline and diesel are among the most common soil and groundwater contaminants. Dissolution and subsequent advective transport of LNAPL components can negatively impact downgradient water supplies, while biodegradation is commonly thought to be an important sink for this class of contaminants. Water-table fluctuations, either naturally occurring or intentionally induced, may affect LNAPL component transport and biodegradation in aquifers. We present a laboratory investigation of the effect of water-table fluctuations on the dissolution and biodegradation of a multi-component LNAPL in a pair of similar model aquifers, one of which was subjected to a water-table fluctuation. Water-table fluctuation resulted in LNAPL and air entrapment below the water table, an increase in the vertical extent of LNAPL contamination and an increase in the volume of water passing through the contaminated zone. Effluent concentrations of dissolved LNAPL components were higher and those of dissolved nitrate were lower in the aquifer model where a fluctuation had been induced. Thus, water table fluctuation led to enhanced LNAPL dissolution as well as enhanced biodegradation activity. The increase in biodegradation observed after fluctuation was of lesser magnitude than the increase in LNAPL dissolution, such that water-table fluctuations might be expected to result in increased exposure of downgradient receptors to dissolved LNAPL components. Conversely, the potential for free-phase LNAPL migration was reduced following a water-table fluctuation, as LNAPL entrapment by the rising water table reduced the amount of free phase LNAPL. Lateral migration of LNAPL following emplacement was observed in the model aquifer where no fluctuation occurred, but not in the model aquifer where a water-table fluctuation was induced.

  6. Simulating the influence of groundwater table fluctuation on vapor intrusion

    NASA Astrophysics Data System (ADS)

    Huo, J.

    2017-12-01

    The migration of volatile chemicals from groundwater to an overlying building is a commonly existing phenomenon around the world. Due to the distinction of hydrologic conditions among vapor intrusion sites, it is necessary to consider the effect of dominant hydrologic factors in order to obtain a precise site evaluation and a health risk assessment during the screening process. This study mainly discusses the impact of groundwater table fluctuation and other hydrological factors including porosity, permeability and soil moisture on the vapor intrusion transport. A two-dimensional model is configured to inject different typical volatile organic contaminants from EPA's Vapor Intrusion Database. Through quantifying the contaminant vapor concentration attenuation factors under the effect of groundwater table fluctuation, this study provides suggestions for indoor air sample and vapor intrusion assessment.

  7. Temporal Hyporheic Zone Response to Water Table Fluctuations.

    PubMed

    Malzone, Jonathan M; Anseeuw, Sierra K; Lowry, Christopher S; Allen-King, Richelle

    2016-03-01

    Expansion and contraction of the hyporheic zone due to temporal hydrologic changes between stream and riparian aquifer influence the biogeochemical cycling capacity of streams. Theoretical studies have quantified the control of groundwater discharge on the depth of the hyporheic zone; however, observations of temporal groundwater controls are limited. In this study, we develop the concept of groundwater-dominated differential hyporheic zone expansion to explain the temporal control of groundwater discharge on the hyporheic zone in a third-order stream reach flowing through glacially derived terrain typical of the Great Lakes region. We define groundwater-dominated differential expansion of the hyporheic zone as: differing rates and magnitudes of hyporheic zone expansion in response to seasonal vs. storm-related water table fluctuation. Specific conductance and vertical hydraulic gradient measurements were used to map changes in the hyporheic zone during seasonal water table decline and storm events. Planar and riffle beds were monitored in order to distinguish the cause of increasing hyporheic zone depth. Planar bed seasonal expansion of the hyporheic zone was of a greater magnitude and longer in duration (weeks to months) than storm event expansion (hours to days). In contrast, the hyporheic zone beneath the riffle bed exhibited minimal expansion in response to seasonal groundwater decline compared to storm related expansion. Results indicated that fluctuation in the riparian water table controlled seasonal expansion of the hyporheic zone along the planar bed. This groundwater induced hyporheic zone expansion could increase the potential for biogeochemical cycling and natural attenuation. © 2015, National Ground Water Association.

  8. Prediction of seasonal water-table fluctuations in La Pampa and Buenos Aires, Argentina

    NASA Astrophysics Data System (ADS)

    Tanco, Raúl; Kruse, Eduardo

    2001-07-01

    The fluctuation of the water table east of La Pampa province and northwest of Buenos Aires province, Argentina, influences agricultural production in the region because it is closely related to the alternation of dry and wet periods. Sea-surface temperature (SST) anomalies have been used as predictors to forecast atmospheric variables in different regions of the world. The objective of this work is to present a simple model to forecast seasonal rainfall using SST distribution in the Pacific Ocean as a predictor. Once the relationship between precipitation and water-table fluctuations was established, a methodology for the prediction of water-table fluctuations was developed. A good agreement between observed and predicted water-table fluctuations was found when estimating water-table fluctuations in the summer and autumn seasons. Résumé. Les fluctuations de la nappe à l'est de la province de La Pampa et au nord-ouest de la province de Buenos Aires (Argentine) influence la production agricole de la région parce qu'elle est étroitement liée à l'alternance de saisons sèches et humides. Les anomalies de la température de surface de l'océan (SST) ont été utilisées comme prédicteurs pour prévoir les variables atmosphériques dans différentes régions du monde. L'objectif de ce travail est de présenter un modèle simple de prévision des précipitations saisonnières en utilisant comme prédicteur la distribution des SST dans l'Océan Pacifique. Une fois que la relation entre les fluctuations des précipitations et celles de la nappe a été établie, une méthodologie de prédiction des variations de la nappe a été mise au point. Un bon accord entre les variations de la nappe observées et celles prédites a été trouvé pour les estimations des variations de nappe en été et en automne. Resumen. La fluctuación del nivel freático al este de la provincia de La Pampa y al nordeste de la de Buenos Aires (Argentina) repercute en la producción agr

  9. Paleoclimatic Inferences from a 120,000-Yr Calcite Record of Water-Table Fluctuation in Browns Room of Devils Hole, Nevada

    USGS Publications Warehouse

    Szabo, B. J.; Kolesar, Peter T.; Riggs, A.C.; Winograd, I.J.; Ludwig, K. R.

    1994-01-01

    The petrographic and morphologic differences between calcite precipitated below, at, or above the present water table and uranium-series dating were used to reconstruct a chronology of water-table fluctuation for the past 120,000 yr in Browns Room, a subterranean air-filled chamber of Devils Hole fissure adjacent to the discharge area of the large Ash Meadows groundwater flow system in southern Nevada. The water table was more than 5 m above present level between about 116,000 and 53,000 yr ago, fluctuated between about +5 and +9 m during the period between about 44,000 and 20,000 yr ago, and declined rapidly from +9 to its present level during the past 20,000 yr. Because the Ash Meadows groundwater basin is greater than 12,000 km2 in extent, these documented water-table fluctuations are likely to be of regional significance. Although different in detail, water-level fluctuation recorded by Browns Room calcites generally correlate with other Great Basin proxy palcoclimatic data.

  10. Predictability and Quantification of Complex Groundwater Table Dynamics Driven by Irregular Surface Water Fluctuations

    NASA Astrophysics Data System (ADS)

    Xin, Pei; Wang, Shen S. J.; Shen, Chengji; Zhang, Zeyu; Lu, Chunhui; Li, Ling

    2018-03-01

    Shallow groundwater interacts strongly with surface water across a quarter of global land area, affecting significantly the terrestrial eco-hydrology and biogeochemistry. We examined groundwater behavior subjected to unimodal impulse and irregular surface water fluctuations, combining physical experiments, numerical simulations, and functional data analysis. Both the experiments and numerical simulations demonstrated a damped and delayed response of groundwater table to surface water fluctuations. To quantify this hysteretic shallow groundwater behavior, we developed a regression model with the Gamma distribution functions adopted to account for the dependence of groundwater behavior on antecedent surface water conditions. The regression model fits and predicts well the groundwater table oscillations resulting from propagation of irregular surface water fluctuations in both laboratory and large-scale aquifers. The coefficients of the Gamma distribution function vary spatially, reflecting the hysteresis effect associated with increased amplitude damping and delay as the fluctuation propagates. The regression model, in a relatively simple functional form, has demonstrated its capacity of reproducing high-order nonlinear effects that underpin the surface water and groundwater interactions. The finding has important implications for understanding and predicting shallow groundwater behavior and associated biogeochemical processes, and will contribute broadly to studies of groundwater-dependent ecology and biogeochemistry.

  11. A generalized groundwater fluctuation model based on precipitation for estimating water table levels of deep unconfined aquifers

    NASA Astrophysics Data System (ADS)

    Jeong, Jina; Park, Eungyu; Shik Han, Weon; Kim, Kue-Young; Suk, Heejun; Beom Jo, Si

    2018-07-01

    A generalized water table fluctuation model based on precipitation was developed using a statistical conceptualization of unsaturated infiltration fluxes. A gamma distribution function was adopted as a transfer function due to its versatility in representing recharge rates with temporally dispersed infiltration fluxes, and a Laplace transformation was used to obtain an analytical solution. To prove the general applicability of the model, convergences with previous water table fluctuation models were shown as special cases. For validation, a few hypothetical cases were developed, where the applicability of the model to a wide range of unsaturated zone conditions was confirmed. For further validation, the model was applied to water table level estimations of three monitoring wells with considerably thick unsaturated zones on Jeju Island. The results show that the developed model represented the pattern of hydrographs from the two monitoring wells fairly well. The lag times from precipitation to recharge estimated from the developed system transfer function were found to agree with those from a conventional cross-correlation analysis. The developed model has the potential to be adopted for the hydraulic characterization of both saturated and unsaturated zones by being calibrated to actual data when extraneous and exogenous causes of water table fluctuation are limited. In addition, as it provides reference estimates, the model can be adopted as a tool for surveilling groundwater resources under hydraulically stressed conditions.

  12. Discrete-storm water-table fluctuation method to estimate episodic recharge.

    USGS Publications Warehouse

    Nimmo, John R.; Horowittz, Charles; Mitchell, Lara

    2015-01-01

    We have developed a method to identify and quantify recharge episodes, along with their associated infiltration-related inputs, by a consistent, systematic procedure. Our algorithm partitions a time series of water levels into discrete recharge episodes and intervals of no episodic recharge. It correlates each recharge episode with a specific interval of rainfall, so storm characteristics such as intensity and duration can be associated with the amount of recharge that results. To be useful in humid climates, the algorithm evaluates the separability of events, so that those whose recharge cannot be associated with a single storm can be appropriately lumped together. Elements of this method that are subject to subjectivity in the application of hydrologic judgment are values of lag time, fluctuation tolerance, and master recession parameters. Because these are determined once for a given site, they do not contribute subjective influences affecting episode-to-episode comparisons. By centralizing the elements requiring scientific judgment, our method facilitates such comparisons by keeping the most subjective elements openly apparent, making it easy to maintain consistency. If applied to a period of data long enough to include recharge episodes with broadly diverse characteristics, the method has value for predicting how climatic alterations in the distribution of storm intensities and seasonal duration may affect recharge.

  13. Field data and numerical simulation of btex concentration trends under water table fluctuations: Example of a jet fuel-contaminated site in Brazil

    NASA Astrophysics Data System (ADS)

    Teramoto, Elias Hideo; Chang, Hung Kiang

    2017-03-01

    Mass transfer of light non-aqueous phase liquids (LNAPLs) trapped in porous media is a complex phenomenon. Water table fluctuations have been identified as responsible for generating significant variations in the concentration of dissolved hydrocarbons. Based on field evidence, this work presents a conceptual model and a numerical solution for mass transfer from entrapped LNAPL to groundwater controlled by both LNAPL saturation and seasonal water table fluctuations within the LNAPL smear zone. The numerical approach is capable of reproducing aqueous BTEX concentration trends under three different scenarios - water table fluctuating within smear zone, above the smear zone and partially within smear zone, resulting in in-phase, out-of-phase and alternating in-phase and out-of-phase BTEX concentration trend with respect to water table oscillation, respectively. The results demonstrate the model's applicability under observed field conditions and its ability to predict source zone depletion.

  14. Discrete-storm water-table fluctuation method to estimate episodic recharge.

    PubMed

    Nimmo, John R; Horowitz, Charles; Mitchell, Lara

    2015-01-01

    We have developed a method to identify and quantify recharge episodes, along with their associated infiltration-related inputs, by a consistent, systematic procedure. Our algorithm partitions a time series of water levels into discrete recharge episodes and intervals of no episodic recharge. It correlates each recharge episode with a specific interval of rainfall, so storm characteristics such as intensity and duration can be associated with the amount of recharge that results. To be useful in humid climates, the algorithm evaluates the separability of events, so that those whose recharge cannot be associated with a single storm can be appropriately lumped together. Elements of this method that are subject to subjectivity in the application of hydrologic judgment are values of lag time, fluctuation tolerance, and master recession parameters. Because these are determined once for a given site, they do not contribute subjective influences affecting episode-to-episode comparisons. By centralizing the elements requiring scientific judgment, our method facilitates such comparisons by keeping the most subjective elements openly apparent, making it easy to maintain consistency. If applied to a period of data long enough to include recharge episodes with broadly diverse characteristics, the method has value for predicting how climatic alterations in the distribution of storm intensities and seasonal duration may affect recharge. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  15. Field data and numerical simulation of btex concentration trends under water table fluctuations: Example of a jet fuel-contaminated site in Brazil.

    PubMed

    Teramoto, Elias Hideo; Chang, Hung Kiang

    2017-03-01

    Mass transfer of light non-aqueous phase liquids (LNAPLs) trapped in porous media is a complex phenomenon. Water table fluctuations have been identified as responsible for generating significant variations in the concentration of dissolved hydrocarbons. Based on field evidence, this work presents a conceptual model and a numerical solution for mass transfer from entrapped LNAPL to groundwater controlled by both LNAPL saturation and seasonal water table fluctuations within the LNAPL smear zone. The numerical approach is capable of reproducing aqueous BTEX concentration trends under three different scenarios - water table fluctuating within smear zone, above the smear zone and partially within smear zone, resulting in in-phase, out-of-phase and alternating in-phase and out-of-phase BTEX concentration trend with respect to water table oscillation, respectively. The results demonstrate the model's applicability under observed field conditions and its ability to predict source zone depletion. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Estimating groundwater recharge uncertainty from joint application of an aquifer test and the water-table fluctuation method

    NASA Astrophysics Data System (ADS)

    Delottier, H.; Pryet, A.; Lemieux, J. M.; Dupuy, A.

    2018-05-01

    Specific yield and groundwater recharge of unconfined aquifers are both essential parameters for groundwater modeling and sustainable groundwater development, yet the collection of reliable estimates of these parameters remains challenging. Here, a joint approach combining an aquifer test with application of the water-table fluctuation (WTF) method is presented to estimate these parameters and quantify their uncertainty. The approach requires two wells: an observation well instrumented with a pressure probe for long-term monitoring and a pumping well, located in the vicinity, for the aquifer test. The derivative of observed drawdown levels highlights the necessity to represent delayed drainage from the unsaturated zone when interpreting the aquifer test results. Groundwater recharge is estimated with an event-based WTF method in order to minimize the transient effects of flow dynamics in the unsaturated zone. The uncertainty on groundwater recharge is obtained by the propagation of the uncertainties on specific yield (Bayesian inference) and groundwater recession dynamics (regression analysis) through the WTF equation. A major portion of the uncertainty on groundwater recharge originates from the uncertainty on the specific yield. The approach was applied to a site in Bordeaux (France). Groundwater recharge was estimated to be 335 mm with an associated uncertainty of 86.6 mm at 2σ. By the use of cost-effective instrumentation and parsimonious methods of interpretation, the replication of such a joint approach should be encouraged to provide reliable estimates of specific yield and groundwater recharge over a region of interest. This is necessary to reduce the predictive uncertainty of groundwater management models.

  17. Estimating evapotranspiration and groundwater flow from water-table fluctuations for a general wetland scenario

    USGS Publications Warehouse

    Carlson Mazur, Martha L.; Michael J. Wiley,; Douglas A. Wilcox,

    2015-01-01

    The use of diurnal water-table fluctuation methods to calculate evapotranspiration (ET) and groundwater flow is of increasing interest in ecohydrological studies. Most studies of this type, however, have been located in riparian wetlands of semi-arid regions where groundwater levels are consistently below topographic surface elevations and precipitation events are infrequent. Current methodologies preclude application to a wider variety of wetland systems. In this study, we extended a method for estimating sub-daily ET and groundwater flow rates from water-level fluctuations to fit highly dynamic, non-riparian wetland scenarios. Modifications included (1) varying the specific yield to account for periodic flooded conditions and (2) relating empirically derived ET to estimated potential ET for days when precipitation events masked the diurnal signal. To demonstrate the utility of this method, we estimated ET and groundwater fluxes over two growing seasons (2006–2007) in 15 wetlands within a ridge-and-swale wetland complex of the Laurentian Great Lakes under flooded and non-flooded conditions. Mean daily ET rates for the sites ranged from 4.0 mm d−1 to 6.6 mm d−1. Shallow groundwater discharge rates resulting from evaporative demand ranged from 2.5 mm d−1 to 4.3 mm d−1. This study helps to expand our understanding of the evapotranspirative demand of plants under various hydrologic and climate conditions.

  18. Estimating evapotranspiration and groundwater flow from water-table fluctuations for a general wetland scenario

    USGS Publications Warehouse

    Weber, Lisa C.; Wiley, Michael J.; Wilcox, Douglas A.

    2016-01-01

    The use of diurnal water-table fluctuation methods to calculate evapotranspiration (ET) and groundwater flow is of increasing interest in ecohydrological studies. Most studies of this type, however, have been located in riparian wetlands of semi-arid regions where groundwater levels are consistently below topographic surface elevations and precipitation events are infrequent. Current methodologies preclude application to a wider variety of wetland systems. In this study, we extended a method for estimating sub-daily ET and groundwater flow rates from water-level fluctuations to fit highly dynamic, non-riparian wetland scenarios. Modifications included (1) varying the specific yield to account for periodic flooded conditions and (2) relating empirically derived ET to estimated potential ET for days when precipitation events masked the diurnal signal. To demonstrate the utility of this method, we estimated ET and groundwater fluxes over two growing seasons (2006–2007) in 15 wetlands within a ridge-and-swale wetland complex of the Laurentian Great Lakes under flooded and non-flooded conditions. Mean daily ET rates for the sites ranged from 4.0 mm d−1 to 6.6 mm d−1. Shallow groundwater discharge rates resulting from evaporative demand ranged from 2.5 mm d−1 to 4.3 mm d−1. This study helps to expand our understanding of the evapotranspirative demand of plants under various hydrologic and climate conditions. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  19. Estimating groundwater evapotranspiration by a subtropical pine plantation using diurnal water table fluctuations: Implications from night-time water use

    NASA Astrophysics Data System (ADS)

    Fan, Junliang; Ostergaard, Kasper T.; Guyot, Adrien; Fujiwara, Stephen; Lockington, David A.

    2016-11-01

    Exotic pine plantations have replaced large areas of the native forests for timber production in the subtropical coastal Australia. To evaluate potential impacts of changes in vegetation on local groundwater discharge, we estimated groundwater evapotranspiration (ETg) by the pine plantation using diurnal water table fluctuations for the dry season of 2012 from August 1st to December 31st. The modified White method was used to estimate the ETg, considering the night-time water use by pine trees (Tn). Depth-dependent specific yields were also determined both experimentally and numerically for estimation of ETg. Night-time water use by pine trees was comprehensively investigated using a combination of groundwater level, sap flow, tree growth, specific yield, soil matric potential and climatic variables measurements. Results reveal a constant average transpiration flux of 0.02 mm h-1 at the plot scale from 23:00 to 05:00 during the study period, which verified the presence of night-time water use. The total ETg for the period investigated was 259.0 mm with an accumulated Tn of 64.5 mm, resulting in an error of 25% on accumulated evapotranspiration from the groundwater if night-time water use was neglected. The results indicate that the development of commercial pine plantations may result in groundwater losses in these areas. It is also recommended that any future application of diurnal water table fluctuation based methods investigate the validity of the zero night-time water use assumption prior to use.

  20. Influence of tidal fluctuations in the water table and methods applied in the calculation of hydrogeological parameters. The case of Motril-Salobreña coastal aquifer

    NASA Astrophysics Data System (ADS)

    Sánchez Úbeda, Juan Pedro; Calvache Quesada, María Luisa; Duque Calvache, Carlos; López Chicano, Manuel; Martín Rosales, Wenceslao

    2013-04-01

    The hydraulic properties of coastal aquifer are essential for any estimation of groundwater flow with simple calculations or modelling techniques. Usually the application of slug test or tracers test are the techniques selected for solving the uncertainties. Other methods are based on the information associated to the changes induced by tidal fluctuation in coastal zones. The Tidal Response Method is a simple technique based in two different factors, tidal efficiency factor and time lag of the tidal oscillation regarding to hydraulic head oscillation caused into the aquifer. This method was described for a homogeneous and isotropic confined aquifer; however, it's applicable to unconfined aquifers when the ratio of maximum water table fluctuation and the saturated aquifer thickness is less than 0.02. Moreover, the tidal equations assume that the tidal signal follows a sinusoidal wave, but actually, the tidal wave is a set of simple harmonic components. Due to this, another methods based in the Fourier series have been applied in earlier studies trying to describe the tidal wave. Nevertheless, the Tidal Response Method represents an acceptable and useful technique in the Motril-Salobreña coastal aquifer. From recently hydraulic head data sets at discharge zone of the Motril-Salobreña aquifer have been calculated transmissivity values using different methods based in the tidal fluctuations and its effects on the hydraulic head. The effects of the tidal oscillation are detected in two boreholes of 132 m and 38 m depth located 300 m to the coastline. The main difficulties for the application of the method were the consideration of a confined aquifer and the variation of the effect at different depths (that is not included into the tidal equations), but these troubles were solved. In one hand, the assumption that the storage coefficient (S) in this unconfined aquifer is close to confined aquifers values due to the hydrogeological conditions at high depth and without

  1. A New Compression Method for FITS Tables

    NASA Technical Reports Server (NTRS)

    Pence, William; Seaman, Rob; White, Richard L.

    2010-01-01

    As the size and number of FITS binary tables generated by astronomical observatories increases, so does the need for a more efficient compression method to reduce the amount disk space and network bandwidth required to archive and down1oad the data tables. We have developed a new compression method for FITS binary tables that is modeled after the FITS tiled-image compression compression convention that has been in use for the past decade. Tests of this new method on a sample of FITS binary tables from a variety of current missions show that on average this new compression technique saves about 50% more disk space than when simply compressing the whole FITS file with gzip. Other advantages of this method are (1) the compressed FITS table is itself a valid FITS table, (2) the FITS headers remain uncompressed, thus allowing rapid read and write access to the keyword values, and (3) in the common case where the FITS file contains multiple tables, each table is compressed separately and may be accessed without having to uncompress the whole file.

  2. Electrical Resistivity Imaging of Tidal Fluctuations in the Water Table at Inwood Hill Park, Manhattan

    NASA Astrophysics Data System (ADS)

    Kenyon, P. M.; Kassem, D.; Olin, A.; Nunez, J.; Smalling, A.

    2005-05-01

    Inwood Hill Park is located on the northern tip of Manhattan and has been extensively modified over the years by human activities. In its current form, it has a backbone of exposed or lightly covered bedrock along the Hudson River, adjacent to a flat area with two tidal inlets along the northern shore of Manhattan. The tidal motions in the inlets are expected to drive corresponding fluctuations in the water table along the borders of the inlets. In the Fall of 2002, a group of students from the Department of Earth and Atmospheric Sciences at the City College of New York studied these fluctuations. Electrical resistivity cross sections were obtained with a Syscal Kid Switch 24 resistivity meter during the course of a tidal cycle at three locations surrounding the westernmost inlet in the park. No change was seen over a tidal cycle at Site 1, possibly due to the effect of concrete erosion barriers which were located between the land and the water surrounding this site. Measurements at Site 2 revealed a small, regular change in the water table elevation of approximately 5 cm over the course of a tidal cycle. This site is inferred to rest on alluvial sediments deposited by a small creek. The cross sections taken at different times during a tidal cycle at Site 3 were the most interesting. They show a very heterogeneous subsurface, with water spurting between blocks of high resistivity materials during the rising portion of the cycle. A small sinkhole was observed on the surface of the ground directly above an obvious plume of water in the cross section. Park personnel confirmed that this sinkhole, like others scattered around this site, is natural and not due to recent construction activity. They also indicated that debris from the construction of the New York City subways may have been dumped in the area in the past. Our conclusion is that the tidal fluctuations at Site 3 are being channeled by solid blocks in the construction debris, and that the sinkholes currently

  3. Dynamics of water-table fluctuations in an upland between two prairie-pothole wetlands in North Dakota

    USGS Publications Warehouse

    Rosenberry, Donald O.; Winter, Thomas C.

    1997-01-01

    Data from a string of instrumented wells located on an upland of 55 m width between two wetlands in central North Dakota, USA, indicated frequent changes in water-table configuration following wet and dry periods during 5 years of investigation. A seasonal wetland is situated about 1.5 m higher than a nearby semipermanent wetland, suggesting an average ground water-table gradient of 0.02. However, water had the potential to flow as ground water from the upper to the lower wetland during only a few instances. A water-table trough adjacent to the lower semipermanent wetland was the most common water-table configuration during the first 4 years of the study, but it is likely that severe drought during those years contributed to the longevity and extent of the water-table trough. Water-table mounds that formed in response to rainfall events caused reversals of direction of flow that frequently modified the more dominant water-table trough during the severe drought. Rapid and large water-table rise to near land surface in response to intense rainfall was aided by the thick capillary fringe. One of the wettest summers on record ended the severe drought during the last year of the study, and caused a larger-scale water-table mound to form between the two wetlands. The mound was short in duration because it was overwhelmed by rising stage of the higher seasonal wetland which spilled into the lower wetland. Evapotranspiration was responsible for generating the water-table trough that formed between the two wetlands. Estimation of evapotranspiration based on diurnal fluctuations in wells yielded rates that averaged 3–5 mm day−1. On many occasions water levels in wells closer to the semipermanent wetland indicated a direction of flow that was different from the direction indicated by water levels in wells farther from the wetland. Misinterpretation of direction and magnitude of gradients between ground water and wetlands could result from poorly placed or too few

  4. Fluctuating ideal-gas lattice Boltzmann method with fluctuation dissipation theorem for nonvanishing velocities.

    PubMed

    Kaehler, G; Wagner, A J

    2013-06-01

    Current implementations of fluctuating ideal-gas descriptions with the lattice Boltzmann methods are based on a fluctuation dissipation theorem, which, while greatly simplifying the implementation, strictly holds only for zero mean velocity and small fluctuations. We show how to derive the fluctuation dissipation theorem for all k, which was done only for k=0 in previous derivations. The consistent derivation requires, in principle, locally velocity-dependent multirelaxation time transforms. Such an implementation is computationally prohibitively expensive but, with a small computational trick, it is feasible to reproduce the correct FDT without overhead in computation time. It is then shown that the previous standard implementations perform poorly for non vanishing mean velocity as indicated by violations of Galilean invariance of measured structure factors. Results obtained with the method introduced here show a significant reduction of the Galilean invariance violations.

  5. Climate change and water table fluctuation: Implications for raised bog surface variability

    NASA Astrophysics Data System (ADS)

    Taminskas, Julius; Linkevičienė, Rita; Šimanauskienė, Rasa; Jukna, Laurynas; Kibirkštis, Gintautas; Tamkevičiūtė, Marija

    2018-03-01

    Cyclic peatland surface variability is influenced by hydrological conditions that highly depend on climate and/or anthropogenic activities. A low water level leads to a decrease of peatland surface and an increase of C emissions into the atmosphere, whereas a high water level leads to an increase of peatland surface and carbon sequestration in peatlands. The main aim of this article is to evaluate the influence of hydrometeorological conditions toward the peatland surface and its feedback toward the water regime. A regional survey of the raised bog water table fluctuation and surface variability was made in one of the largest peatlands in Lithuania. Two appropriate indicators for different peatland surface variability periods (increase and decrease) were detected. The first one is an 200 mm y- 1 average net rainfall over a three-year range. The second one is an average annual water depth of 25-30 cm. The application of these indicators enabled the reconstruction of Čepkeliai peatland surface variability during a 100 year period. Processes of peatland surface variability differ in time and in separate parts of peatland. Therefore, internal subbasins in peatland are formed. Subbasins involve autogenic processes that can later affect their internal hydrology, nutrient status, and vegetation succession. Internal hydrological conditions, surface fluctuation, and vegetation succession in peatland subbasins should be taken into account during evaluation of their state, nature management projects, and other peatland research works.

  6. Magnetic properties changes due to hydrocarbon contaminated groundwater table fluctuations

    NASA Astrophysics Data System (ADS)

    Ameen, Nawrass

    2013-04-01

    This study aims to understand the mechanisms and conditions which control the formation and transformation of ferro(i)magnetic minerals caused by hydrocarbon contaminated groundwater, in particular in the zone of fluctuating water levels. The work extends previous studies conducted at the same site. The study area is a former military air base at Hradčany, Czech Republic (50°37'22.71"N, 14°45'2.24"E). The site was heavily contaminated with petroleum hydrocarbons, due to leaks in petroleum storage tanks and jet fuelling stations over years of active use by the Soviet Union, which closed the base in 1991. The site is one of the most important sources of high quality groundwater in the Czech Republic. In a previous study, Rijal et al. (2010) concluded that the contaminants could be flushed into the sediments as the water level rose due to remediation processes leading to new formation of magnetite. In this previous study three different locations were investigated; however, from each location only one core was obtained. In order to recognize significant magnetic signatures versus depth three cores from each of these three locations were drilled in early 2012, penetrating the unsaturated zone, the groundwater fluctuation (GWF) zone and extending to about one meter below the groundwater level (~2.3 m depth at the time of sampling). Magnetic susceptibility (MS) profiles combined with other magnetic properties were analyzed to obtain a significant depth distribution of the ferro(i)magnetic concentration. Sediment properties, hydrocarbon content and bacterial activity were additionally studied. The results show that the highest ferrimagnetic mineral concentrations exist between 1.4-1.9 m depth from the baseline which is interpreted as the top of the GWF zone. Spikes of MS detected in the previous studies turned out to represent small-scale isolated features, but the trend of increasing MS values from the lowermost position of the groundwater table upward was verified

  7. The influence of irrigation-induced water table fluctuation on iron redistribution and arsenic immobilization within the unsaturation zone.

    PubMed

    Chi, Zeyong; Xie, Xianjun; Pi, Kunfu; Wang, Yanxin; Li, Junxia; Qian, Kun

    2018-05-08

    Given the long-term potential risk of arsenic (As)-contaminated agricultural soil to public health, the redistribution of iron (Fe) and immobilization of As within the unsaturation zone during irrigation and consequent water table fluctuations were studied via a column experiment and corresponding geochemical modeling. Experimental results show that As and Fe accumulated significantly at the top of the column during irrigation. A tremendous increase in As and Fe accumulation rates exists after water table recovery. It was deduced that Fe(II) and As(III) were oxidized directly by O 2 at the period of low water table. But the production of hydroxyl radical (OH) was promoted at the period of high water table due to the oxidation of adsorbed Fe(II). The generated OH further accelerate the oxidation of Fe(II) and As(III). Moreover, the combination of As and Fe is more stronger at the top of the column due to the transformation of combined states of As from surface complexation into surface precipitation with the growth of Fe(III) minerals. This study details the processes and mechanisms of As and Fe immobilization within the unsaturation zone during different irrigation periods and accordingly provides some insights to mitigate As accumulation in topsoil. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Predicting the past: a simple reverse stand table projection method

    Treesearch

    Quang V. Cao; Shanna M. McCarty

    2006-01-01

    A stand table gives number of trees in each diameter class. Future stand tables can be predicted from current stand tables using a stand table projection method. In the simplest form of this method, a future stand table can be expressed as the product of a matrix of transitional proportions (based on diameter growth rates) and a vector of the current stand table. There...

  9. 40 CFR Table 3 of Subpart Aaaaaaa... - Test Methods

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 15 2014-07-01 2014-07-01 false Test Methods 3 Table 3 of Subpart..., Subpt. AAAAAAA, Table 3 Table 3 of Subpart AAAAAAA of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A in...

  10. 40 CFR Table 3 of Subpart Aaaaaaa... - Test Methods

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 15 2012-07-01 2012-07-01 false Test Methods 3 Table 3 of Subpart..., Subpt. AAAAAAA, Table 3 Table 3 of Subpart AAAAAAA of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A in...

  11. 40 CFR Table 3 of Subpart Aaaaaaa... - Test Methods

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 14 2011-07-01 2011-07-01 false Test Methods 3 Table 3 of Subpart..., Subpt. AAAAAAA, Table 3 Table 3 of Subpart AAAAAAA of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A in...

  12. 40 CFR Table 3 of Subpart Aaaaaaa... - Test Methods

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 14 2010-07-01 2010-07-01 false Test Methods 3 Table 3 of Subpart..., Subpt. AAAAAAA, Table 3 Table 3 of Subpart AAAAAAA of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A in...

  13. 40 CFR Table 3 of Subpart Aaaaaaa... - Test Methods

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 15 2013-07-01 2013-07-01 false Test Methods 3 Table 3 of Subpart..., Subpt. AAAAAAA, Table 3 Table 3 of Subpart AAAAAAA of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A in...

  14. Monthly fluctuations in the quality of ground water near the water table in Nassau and Suffolk Counties, Long Island, New York

    USGS Publications Warehouse

    Katz, Brian G.; Ragone, Stephen E.; Lindner-Lunsford, Juli B.

    1978-01-01

    Water samples from wells in a sewered and an unsewered suburban area and an unsewered rural area on Long Island, N.Y. were collected and analyzed monthly from August 1975 to July 1976 to determine the concentrations of chloride, sulfate, and nitrate in ground water near the water table. Short-term and seasonal fluctuations in concentrations of these substances were evaluated to determine their relation to nonpoint discharges. Major factors that may cause concentrations of these substances to fluctuate at any particular site are precipitation, lawn fertilizer, dissolved salts in storm runoff, and effluent from septic tanks and cesspools. Chloride concentrations during the study fluctuated by as little as 2 milligrams per liter (mg/liter) at some sites and as much as 300 mg/liter at others. Nitrate and sulfate concentrations showed essentially no change at some sites but fluctuated by as much as 8 and 40 mg/liter, respectively, at others. Short-term fluctuations in the concentrations of these substances in ground water seem to have no consistent correlation with type of land use (suburban or agricultural) or precipitation but seem to be related to seasonal variations in input from specific nonpoint sources. (Woodard-USGS)

  15. The radio-frequency fluctuation effect on the floating harmonic method

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

    Lee, Jaewon; Kim, Kyung-Hyun; Kim, Dong-Hwan

    2016-08-15

    The radio-frequency (RF) plasma diagnostics with an electrical probe facing a challenge, because the RF fluctuation oscillates the plasma potential and distorts the current-voltage (I-V) curve. As Langmuir probe is widely used in plasma diagnostics, many researchers have been studying the effect of RF fluctuation on probe and compensation methods. On the other hand, there have not been enough studies on the fluctuation effect on the floating harmonic method. Therefore, we investigated the impact of RF fluctuation on the floating harmonic method theoretically and experimentally. When the electrons are in ideal Maxwellian distribution, the floating potential is negatively shifted bymore » the RF fluctuation, but the fluctuation does not distort I-V curve around the floating potential. However, in practical plasmas, the I-V curve and their harmonic components are distorted. This RF fluctuation effect becomes more significant in a low density plasma with a high impedance sheath. The second harmonic current decreases with the RF fluctuation while the first harmonic current is merely affected. Therefore, the electron temperatures measured with the floating harmonic method under low density plasma with uncompensated probe are overestimated than the results obtained with the compensated probe.« less

  16. Ground Water Recharge Estimation Using Water Table Fluctuation Method And By GIS Applications

    NASA Astrophysics Data System (ADS)

    Vajja, V.; Bekkam, V.; Nune, R.; M. v. S, R.

    2007-05-01

    Quite often it has become a debating point that how much recharge is occurring to the groundwater table through rainfall on one hand and through recharge structures such as percolation ponds and checkdams on the other. In the present investigations Musi basin of Andhra Pradesh, India is selected for study during the period 2005-06. Pre-monsoon and Post-monsoon groundwater levels are collected through out the Musi basin at 89 locations covering an area11, 291.69 km2. Geology of the study area and rainfall data during the study period has been collected. The contour maps of rainfall and the change in groundwater level between Pre-monsoon and Post- monsoon have been prepared. First the change in groundwater storage is estimated for each successive strips of areas enclosed between two contours of groundwater level fluctuations. In this calculation Specific yield (Sy) values are adopted based on the local Geology. Areas between the contours are estimated through Arc GIS software package. All such storages are added to compute the total storage for the entire basin. In order to find out the percent of rainfall converted into groundwater storage as well as to find out the ground water recharge due to storageponds, a contour map of rainfall for the study area is prepared and areas between successive contours have been calculated. Based on the Geology map, Infiltration values are adopted for each successive strip of the contour area. Then the amount of water infiltrated into the ground is calculated by adjusting the infiltration values for each strip, so that the total infiltrated water for the entire basin is matched with change in Ground water storage, which is 1314.37 MCM for the upper Musi basin while it is 2827.29 MCM for entire Musi basin. With this procedure on an average 29.68 and 30.66 percent of Rainfall is converted into Groundwater recharge for Upper Musi and for entire Musi basin respectively. In the total recharge, the contribution of rainfall directly to

  17. Early Holocene groundwater table fluctuations in relation to rice domestication in the middle Yangtze River basin, China

    NASA Astrophysics Data System (ADS)

    Liu, Tao; Liu, Yan; Sun, Qianli; Zong, Yongqiang; Finlayson, Brian; Chen, Zhongyuan

    2017-01-01

    The early Holocene environmental amelioration stimulated the trajectory of Neolithic farming cultures and specific geographic settings played a role in determining the nature of these cultures. Using microfossil evidence, the present study reveals that the fluctuations of the groundwater table substantially influenced rice domestication in the Dongting Lake area of the middle Yangtze River basin in the early Holocene. Our 14C-dated sediment core taken from the Bashidang (BSD) Neolithic site contains evidence that the site was a floodplain prior to human occupation ca. 8600 years ago. Poaceae, which contained wild rice (Oryza sp.) as indicated by combined pollen and phytolith evidence, and low counts of freshwater algae indicated a moist site condition. The area then gradually evolved into wetlands as the water table rose, in response to the increasing monsoon precipitation during the early Holocene. This favored rice domestication, assisted by firing and clearing, that continued to flourish for several hundred years. Finally, rice domestication declined during the late stage of the Pengtoushan culture, accompanied by evidence of the expansion of wetlands reflecting the effects of a rising groundwater table that had caused the cessation of rice farming at the Bashidang site after ca. 8000-7900 cal yr BP. This study shows that there are local effects at particular sites that may differ from the trend at the regional scale, necessitating a careful interpretation of the available evidence.

  18. Analysis of Tide and Offshore Storm-Induced Water Table Fluctuations for Structural Characterization of a Coastal Island Aquifer

    NASA Astrophysics Data System (ADS)

    Trglavcnik, Victoria; Morrow, Dean; Weber, Kela P.; Li, Ling; Robinson, Clare E.

    2018-04-01

    Analysis of water table fluctuations can provide important insight into the hydraulic properties and structure of a coastal aquifer system including the connectivity between the aquifer and ocean. This study presents an improved approach for characterizing a permeable heterogeneous coastal aquifer system through analysis of the propagation of the tidal signal, as well as offshore storm pulse signals through a coastal aquifer. Offshore storms produce high wave activity, but are not necessarily linked to significant onshore precipitation. In this study, we focused on offshore storm events during which no onshore precipitation occurred. Extensive groundwater level data collected on a sand barrier island (Sable Island, NS, Canada) show nonuniform discontinuous propagation of the tide and offshore storm pulse signals through the aquifer with isolated inland areas showing enhanced response to both oceanic forcing signals. Propagation analysis suggests that isolated inland water table fluctuations may be caused by localized leakage from a confined aquifer that is connected to the ocean offshore but within the wave setup zone. Two-dimensional groundwater flow simulations were conducted to test the leaky confined-unconfined aquifer conceptualization and to identify the effect of key parameters on tidal signal propagation in leaky confined-unconfined coastal aquifers. This study illustrates that analysis of offshore storm signal propagation, in addition to tidal signal propagation, provides a valuable and low resource approach for large-scale characterization of permeable heterogeneous coastal aquifers. Such an approach is needed for the effective management of coastal environments where water resources are threatened by human activities and the changing climate.

  19. Non-invasive water-table imaging with joint DC-resistivity/microgravity/hydrologic-model inversion

    NASA Astrophysics Data System (ADS)

    Kennedy, J.; Macy, J. P.

    2017-12-01

    The depth of the water table, and fluctuations thereof, is a primary concern in hydrology. In riparian areas, the water table controls when and where vegetation grows. Fluctuations in the water table depth indicate changes in aquifer storage and variation in ET, and may also be responsible for the transport and degradation of contaminants. In the latter case, installation of monitoring wells is problematic because of the potential to create preferential flow pathways. We present a novel method for non-invasive water table monitoring using combined DC resistivity and repeat microgravity data. Resistivity profiles provide spatial resolution, but a quantifiable relation between resistivity changes and aquifer-storage changes depends on a petrophysical relation (typically, Archie's Law), with additional parameters and therefore uncertainty. Conversely, repeat microgravity data provide a direct, quantifiable measurement of aquifer-storage change but lack depth resolution. We show how these two geophysical measurements, together with an unsaturated-zone flow model (Hydrogeosphere), effectively constrain the water table position and help identify groundwater-flow model parameters. A demonstration of the method is made using field data collected during the historic 2014 pulse flow in the Colorado River Delta, which shows that geophysical data can effectively constrain a coupled surface-water/groundwater model used to simulate the potential for riparian vegetation germination and recruitment.

  20. Comparison of detrending methods for fluctuation analysis in hydrology

    NASA Astrophysics Data System (ADS)

    Zhang, Qiang; Zhou, Yu; Singh, Vijay P.; Chen, Yongqin David

    2011-03-01

    SummaryTrends within a hydrologic time series can significantly influence the scaling results of fluctuation analysis, such as rescaled range (RS) analysis and (multifractal) detrended fluctuation analysis (MF-DFA). Therefore, removal of trends is important in the study of scaling properties of the time series. In this study, three detrending methods, including adaptive detrending algorithm (ADA), Fourier-based method, and average removing technique, were evaluated by analyzing numerically generated series and observed streamflow series with obvious relative regular periodic trend. Results indicated that: (1) the Fourier-based detrending method and ADA were similar in detrending practices, and given proper parameters, these two methods can produce similarly satisfactory results; (2) detrended series by Fourier-based detrending method and ADA lose the fluctuation information at larger time scales, and the location of crossover points is heavily impacted by the chosen parameters of these two methods; and (3) the average removing method has an advantage over the other two methods, i.e., the fluctuation information at larger time scales is kept well-an indication of relatively reliable performance in detrending. In addition, the average removing method performed reasonably well in detrending a time series with regular periods or trends. In this sense, the average removing method should be preferred in the study of scaling properties of the hydrometeorolgical series with relative regular periodic trend using MF-DFA.

  1. Depth dependent microbial carbon use efficiency in the capillary fringe as affected by water table fluctuations in a column incubation experiment

    NASA Astrophysics Data System (ADS)

    Pronk, G. J.; Mellage, A.; Milojevic, T.; Smeaton, C. M.; Rezanezhad, F.; Van Cappellen, P.

    2017-12-01

    Microbial growth and turnover of soil organic carbon (SOC) depend on the availability of electron donors and acceptors. The steep geochemical gradients in the capillary fringe between the saturated and unsaturated zones provide hotspots of soil microbial activity. Water table fluctuations and the associated drying and wetting cycles within these zones have been observed to lead to enhanced turnover of SOC and adaptation of the local microbial communities. To improve our understanding of SOC degradation under changing moisture conditions, we carried out an automated soil column experiment with integrated of hydro-bio-geophysical monitoring under both constant and oscillating water table conditions. An artificial soil mixture composed of quartz sand, montmorillonite, goethite and humus was used to provide a well-defined system. This material was inoculated with a microbial community extracted from a forested riparian zone. The soils were packed into 6 columns (60 cm length and 7.5 cm inner diameter) to a height of 45 cm; and three replicate columns were incubated under constant water table while another three were saturated and drained monthly. The initial soil development, carbon cycling and microbial community development were then characterized during 10 months of incubation. This system provides an ideal artificial gradient from the saturated to the unsaturated zone to study soil development from initially homogeneous materials and the same microbial community composition under controlled conditions. Depth profiles of SOC and microbial biomass after 329 days of incubation showed a depletion of carbon in the transition drying and wetting zone that was not associated with higher accumulation of microbial biomass, indicating a lower carbon use efficiency of the microbial community established within the water table fluctuation zone. This was supported by a higher ATP to microbial biomass carbon ratio within the same zone. The findings from this study highlight the

  2. League tables and school effectiveness: a mathematical model.

    PubMed Central

    Hoyle, Rebecca B; Robinson, James C

    2003-01-01

    'School performance tables', an alphabetical list of secondary schools along with aggregates of their pupils' performances in national tests, have been published in the UK since 1992. Inevitably, the media have responded by publishing ranked 'league tables'. Despite concern over the potentially divisive effect of such tables, the current government has continued to publish this information in the same form. The effect of this information on standards and on the social make-up of the community has been keenly debated. Since there is no control group available that would allow us to investigate this issue directly, we present here a simple mathematical model. Our results indicate that, while random fluctuations from year to year can cause large distortions in the league-table positions, some schools still establish themselves as 'desirable'. To our surprise, we found that 'value-added' tables were no more accurate than tables based on raw exam scores, while a different method of drawing up the tables, in which exam results are averaged over a period of time, appears to give a much more reliable measure of school performance. PMID:12590748

  3. Comparison of specific-yield estimates for calculating evapotranspiration from diurnal groundwater-level fluctuations

    NASA Astrophysics Data System (ADS)

    Gribovszki, Zoltán

    2018-05-01

    Methods that use diurnal groundwater-level fluctuations are commonly used for shallow water-table environments to estimate evapotranspiration (ET) and recharge. The key element needed to obtain reliable estimates is the specific yield (Sy), a soil-water storage parameter that depends on unsaturated soil-moisture and water-table fluxes, among others. Soil-moisture profile measurement down to the water table, along with water-table-depth measurements, can provide a good opportunity to calculate Sy values even on a sub-daily scale. These values were compared with Sy estimates derived by traditional techniques, and it was found that slug-test-based Sy values gave the most similar results in a sandy soil environment. Therefore, slug-test methods, which are relatively cheap and require little time, were most suited to estimate Sy using diurnal fluctuations. The reason for this is that the timeframe of the slug-test measurement is very similar to the dynamic of the diurnal signal. The dynamic characteristic of Sy was also analyzed on a sub-daily scale (depending mostly on the speed of drainage from the soil profile) and a remarkable difference was found in Sy with respect to the rate of change of the water table. When comparing constant and sub-daily (dynamic) Sy values for ET estimation, the sub-daily Sy application yielded higher correlation, but only a slightly smaller deviation from the control ET method, compared with the usage of constant Sy.

  4. Magnetic susceptibility as a proxy for the hydrobiogeochemical cycling of iron within the water table fluctuation zone at hydrocarbon contaminated sites

    NASA Astrophysics Data System (ADS)

    Atekwana, E. A.; Enright, A.; Atekwana, E. A.; Beaver, C. L.; Rossbach, S.; Slater, L. D.; Ntarlagiannis, D.

    2016-12-01

    Sharp redox gradients are indicative of enhanced biogeochemical activity and occur at or near the water table. Hydrologic forcing drives changes in redox state and oxygen levels, enhancing the elemental cycling of metals, and coupling different biogeochemical cycles. These coupled hydrobiogeochemical cycles are often difficult to study in the field using geochemical and microbial proxies because of direct sampling limitations, the costs associated with these techniques, and because the dynamic nature of these processes complicates the interpretation of single time point measurements, which may not give accurate representations of prevailing conditions. Geophysical techniques can provide both the spatial and temporal resolution needed to elucidate these processes. Here we investigated the use of magnetic susceptibility (c) as a viable proxy for understanding the biogeochemical cycling of iron at several hydrocarbon contaminated sites where active intrinsic bioremediation is occurring. We performed borehole c logging using a Bartington c probe in the field as well as made c measurements on core samples retrieved from the field sites. Our results show the following: (1) in both sulfate-rich and sulfate-poor aquifers, excursions in c are coincident with zones of free product contamination and are limited to the water table fluctuation (smear) zone; (2) c values within the free product plume and contamination source zones are higher compared to values within the dissolved product plume; (3) high c coincides with zones of elevated Fe (II) and Fe (III) concentrations extracted from aquifer solids; and (4) the mixed valence magnetite and greigite were the dominant magnetic minerals. The c excursions are limited to the water table fluctuation zones because fluctuating water level conditions are hot beds for microbial activity due to the steep hydrocarbon and nutrients and consequently redox gradients. High water levels during periods of recharge favor anaerobic conditions

  5. 40 CFR Table 3 of Subpart Bbbbbbb... - Test Methods

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 14 2011-07-01 2011-07-01 false Test Methods 3 Table 3 of Subpart... 3 Table 3 of Subpart BBBBBBB of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A in appendix A to part 60. 2...

  6. 40 CFR Table 3 of Subpart Bbbbbbb... - Test Methods

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 14 2010-07-01 2010-07-01 false Test Methods 3 Table 3 of Subpart... 3 Table 3 of Subpart BBBBBBB of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A in appendix A to part 60. 2...

  7. 40 CFR Table 3 of Subpart Bbbbbbb... - Test Methods

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 15 2013-07-01 2013-07-01 false Test Methods 3 Table 3 of Subpart... 3 Table 3 of Subpart BBBBBBB of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A in appendix A to part 60. 2...

  8. 40 CFR Table 3 of Subpart Bbbbbbb... - Test Methods

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 15 2014-07-01 2014-07-01 false Test Methods 3 Table 3 of Subpart... 3 Table 3 of Subpart BBBBBBB of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A in appendix A to part 60. 2...

  9. 40 CFR Table 3 of Subpart Bbbbbbb... - Test Methods

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 15 2012-07-01 2012-07-01 false Test Methods 3 Table 3 of Subpart... 3 Table 3 of Subpart BBBBBBB of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A in appendix A to part 60. 2...

  10. Water table depth fluctuations during ENSO phenomenon on different tropical peat swamp forest land covers in Katingan, Indonesia

    NASA Astrophysics Data System (ADS)

    Rossita, A.; Witono, A.; Darusman, T.; Lestari, D. P.; Risdiyanto, I.

    2018-03-01

    As it is the main role to maintain hydrological function, peatland has been a limelight since drainage construction for agriculture evolved. Drainage construction will decrease water table depth (WTD) and result in CO2 emission release to the atmosphere. Regardless of human intervention, WTD fluctuations can be affected by seasonal climate and climate variability, foremost El Niño Southern Oscillation (ENSO). This study aims to determine the correlation between rainfall in Katingan and ENSO index, analyze the pattern of WTD fluctuation of open area and forest area in 2015 (during very strong El Niño) and 2016 (during weak La Niña), calculate the WTD trendline slope during the dry season, and rainfall and WTD correlation. The result showed that open area has a sharper slope of decreasing or increasing WTD when entering the dry, compared to the forest area. Also, it is found that very strong El Niño in 2015 generated a pattern of more extreme decreasing WTD during the dry season than weak La Niña in 2016.

  11. Identity method to study chemical fluctuations in relativistic heavy-ion collisions

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

    Gazdzicki, Marek; Grebieszkow, Katarzyna; Mackowiak, Maja

    Event-by-event fluctuations of the chemical composition of the hadronic final state of relativistic heavy-ion collisions carry valuable information on the properties of strongly interacting matter produced in the collisions. However, in experiments incomplete particle identification distorts the observed fluctuation signals. The effect is quantitatively studied and a new technique for measuring chemical fluctuations, the identity method, is proposed. The method fully eliminates the effect of incomplete particle identification. The application of the identity method to experimental data is explained.

  12. Identity method-a new tool for studying chemical fluctuations

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

    Mackowiak, M., E-mail: majam@if.pw.edu.pl

    Event-by-event fluctuations of the chemical composition of the hadronic system produced in nuclear collisions are believed to be sensitive to properties of the transition between confined and deconfined strongly interacting matter. In this paper a new technique for the study of chemical fluctuation, the identity method, is introduced and its features are discussed. The method is tested using data on central PbPb collisions at 40 A GeV registered by the NA49 experiment at the CERN SPS.

  13. Influence analysis of fluctuation parameters on flow stability based on uncertainty method

    NASA Astrophysics Data System (ADS)

    Meng, Tao; Fan, Shangchun; Wang, Chi; Shi, Huichao

    2018-05-01

    The relationship between flow fluctuation and pressure in a flow facility is studied theoretically and experimentally in this paper, and a method for measuring the flow fluctuation is proposed. According to the synchronicity of pressure and flow fluctuation, the amplitude of the flow fluctuation is calculated using the pressure measured in the flow facility and measurement of the flow fluctuation in a wide range of frequency is realized. Based on the method proposed, uncertainty analysis is used to evaluate the influences of different parameters on the flow fluctuation by the help of a sample-based stochastic model established and the parameters that have great influence are found, which can be a reference for the optimization design and the stability improvement of the flow facility.

  14. Annual safe groundwater yield in a semiarid basin using combination of water balance equation and water table fluctuation

    NASA Astrophysics Data System (ADS)

    Rezaei, Abolfazl; Mohammadi, Zargham

    2017-10-01

    The safe groundwater yield plays a major role in the appropriate management of groundwater systems, particularly in (semi-)arid areas like Iran. This study incorporates both the water balance equation and the water table fluctuation to estimate the annual safe yield of the unconfined aquifer in the eastern part of the Kaftar Lake, an Iranian semiarid region. Firstly, the water balance year 2002-03, owing same water table elevation at the beginning and year-end, was chosen from the monthly representative groundwater hydrograph of the aquifer to be taken into account as a basic water year for determining the safe yield. Then the ratio of the total groundwater pumping to the annual groundwater recharge in the selected water balance year together with the quantity of total recharge occurred in the wet period (October to May) of the year of interest were applied to evaluate the annual safe yield at the initiation of the dry period (June to September) of the year of interest. Knowing the annual safe groundwater withdrawal rate at the initiation of each dry period could be helpful to decision makers in managing groundwater resources conservation. Analysis results indicate that to develop a safe management strategy in the aquifer; the ratio of the annual groundwater withdrawal to the annually recharged volume should not exceed 0.69. In the water year 2003-04 where the ratio is equal to 0.52, the water table raised up (about 0.48 m) while the groundwater level significantly declined (about 1.54 m) over the water year 2007-08 where the ratio of the annual groundwater withdrawal to the annually recharged volume (i.e., 2.76) is larger than 0.69.

  15. Barometric fluctuations in wells tapping deep unconfined aquifers

    USGS Publications Warehouse

    Weeks, Edwin P.

    1979-01-01

    Water levels in wells screened only below the water table in unconfined aquifers fluctuate in response to atmospheric pressure changes. These fluctuations occur because the materials composing the unsaturated zone resist air movement and have capacity to store air with a change in pressure. Consequently, the translation of any pressure change at land surface is slowed as it moves through the unsaturated zone to the water table, but it reaches the water surface in the well instantaneously. Thus a pressure imbalance is created that results in a water level fluctuation. Barometric effects on water levels in unconfined aquifers can be computed by solution of the differential equation governing the flow of gas in the unsaturated zone subject to the appropriate boundary conditions. Solutions to this equation for two sets of boundary conditions were applied to compute water level response in a well tapping the Ogallala Formation near Lubbock, Texas from simultaneous microbarograph records. One set of computations, based on the step function unit response solution and convolution, resulted in a very good match between computed and measured water levels. A second set of computations, based on analysis of the amplitude ratios of simultaneous cyclic microbarograph and water level fluctuations, gave inconsistent results in terms of the unsaturated zone pneumatic properties but provided useful insights on the nature of unconfined-aquifer water level fluctuations.

  16. Improved look-up table method of computer-generated holograms.

    PubMed

    Wei, Hui; Gong, Guanghong; Li, Ni

    2016-11-10

    Heavy computation load and vast memory requirements are major bottlenecks of computer-generated holograms (CGHs), which are promising and challenging in three-dimensional displays. To solve these problems, an improved look-up table (LUT) method suitable for arbitrarily sampled object points is proposed and implemented on a graphics processing unit (GPU) whose reconstructed object quality is consistent with that of the coherent ray-trace (CRT) method. The concept of distance factor is defined, and the distance factors are pre-computed off-line and stored in a look-up table. The results show that while reconstruction quality close to that of the CRT method is obtained, the on-line computation time is dramatically reduced compared with the LUT method on the GPU and the memory usage is lower than that of the novel-LUT considerably. Optical experiments are carried out to validate the effectiveness of the proposed method.

  17. Analyzing and Improving the Water-Table Fluctuation Method of Estimating Groundwater Recharge: Field Considerations Patros, T.B. and Parkin, G.W., School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Patros, T.; Parkin, G. W.

    2012-12-01

    The focus of the project is on measuring and quantifying groundwater recharge (GWR) using the water-table fluctuation (WTF) method. This method requires measuring the change in water-table (WT) height (Δh) during recharge (R) events and volumetric soil specific yield water content (θsy), (&/or) perhaps more correctly volumetric soil fillable water content (θf). The rise in WT can also result from other non-precipitation-related WTF causes (e.g., Lisse effect, temperature variations, barometric, lateral flow, Reverse Wieringermeer effect, encapsulated air, pumping), which must be counted for. The measurement of the storativity (S) terms (θsy) and/or θf) is, indeed, not clear-cut and often they are taken as being constant with depth, time, WT movement (Drying-Wetting & Freezing-Thawing) history and heterogeneity. In fact, these two terms (θsy & θf) are controversial in their definition, thus in their use, in the literature and may either overestimate the R, when using θsy, or underestimate it, when using θf. To resolve some of these questions, a novel-automated method is under development, at the University of Guelph's Elora Research Station (ERS) and Arboretum, along with a novel multi-event time series model. The long-term expected outcomes and significance of this study are; 1. Establishing accuracy in defining and evaluating the θsy and θf and using them accordingly in estimating GWR with the WTF method in order to overcome some of the existing substantial gaps in our knowledge of groundwater (GW) storage variation. 2. Obtaining GWR measurements at the local scale on a year-round basis, which are currently scarce or even completely lacking for many regions of Ontario and thus would provide a valuable database for guiding development of any policy requiring GWR. 3. Using this database to calibrate and test estimates of the spatial and temporal variability in regional-scale (watershed scale) GWR from approximate statistical techniques or deterministic

  18. Microtropography and water table fluctuation in a sphagnum mire

    Treesearch

    E.S. Verry

    1984-01-01

    A detailed organic soil profile description, 22 years of continuous water table records, and a hummock-hollow level survey were examined at a small Minnesota mire (a bog with remnants of poor fen vegetation). Variation in the level survey suggests that hollows be used to minimize variation when detailed topographic information is needed and to match profile...

  19. Peatland pines as a proxy for water table fluctuations: disentangling tree growth, hydrology and possible human influence.

    PubMed

    Smiljanić, Marko; Seo, Jeong-Wook; Läänelaid, Alar; van der Maaten-Theunissen, Marieke; Stajić, Branko; Wilmking, Martin

    2014-12-01

    Dendrochronological investigations of Scots pine (Pinus sylvestris L.) growing on Männikjärve peatland in central Estonia showed that annual tree growth of peatland pines can be used as a proxy for past variations of water table levels. Reconstruction of past water table levels can help us to better understand the dynamics of various ecological processes in peatlands, e.g. the formation of vegetation patterns or carbon and nitrogen cycling. Männikjärve bog has one of the longest water table records in the boreal zone, continuously monitored since 1956. Common uncertainties encountered while working with peatland trees (e.g. narrow, missing and wedging rings) were in our case exacerbated with difficulties related to the instability of the relationship between tree growth and peatland environment. We hypothesized that the instable relationship was mainly due to a significant change of the limiting factor, i.e. the rise of the water table level due to human activity. To test our hypothesis we had to use several novel methods of tree-ring chronology analysis as well as to test explicitly whether undetected missing rings biased our results. Since the hypothesis that the instable relationship between tree growth and environment was caused by a change in limiting factor could not be rejected, we proceeded to find possible significant changes of past water table levels using structural analysis of the tree-ring chronologies. Our main conclusions were that peatland pines can be proxies to water table levels and that there were several shifting periods of high and low water table levels in the past 200 years. Copyright © 2014 Elsevier B.V. All rights reserved.

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

    PubMed

    Harada, Ryuhei; Takano, Yu; Shigeta, Yasuteru

    2014-03-28

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

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

    NASA Astrophysics Data System (ADS)

    Harada, Ryuhei; Takano, Yu; Shigeta, Yasuteru

    2014-03-01

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

  2. A method of reducing background fluctuation in tunable diode laser absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Yang, Rendi; Dong, Xiaozhou; Bi, Yunfeng; Lv, Tieliang

    2018-03-01

    Optical interference fringe is the main factor that leads to background fluctuation in gas concentration detection based on tunable diode laser absorption spectroscopy. The interference fringes are generated by multiple reflections or scatterings upon optical surfaces in optical path and make the background signal present an approximated sinusoidal oscillation. To reduce the fluctuation of the background, a method that combines dual tone modulation (DTM) with vibration reflector (VR) is proposed in this paper. The combination of DTM and VR can make the unwanted periodic interference fringes to be averaged out and the effectiveness of the method in reducing background fluctuation has been verified by simulation and real experiments in this paper. In the detection system based on the proposed method, the standard deviation (STD) value of the background signal is decreased to 0.0924 parts per million (ppm), which is reduced by a factor of 16 compared with that of wavelength modulation spectroscopy. The STD value of 0.0924 ppm corresponds to the absorption of 4 . 328 × 10-6Hz - 1 / 2 (with effective optical path length of 4 m and integral time of 0.1 s). Moreover, the proposed method presents a better stable performance in reducing background fluctuation in long time experiments.

  3. Estimation of groundwater consumption by phreatophytes using diurnal water table fluctuations: A saturated‐unsaturated flow assessment

    USGS Publications Warehouse

    Loheide, Steven P.; Butler, James J.; Gorelick, Steven M.

    2005-01-01

    Groundwater consumption by phreatophytes is a difficult‐to‐measure but important component of the water budget in many arid and semiarid environments. Over the past 70 years the consumptive use of groundwater by phreatophytes has been estimated using a method that analyzes diurnal trends in hydrographs from wells that are screened across the water table (White, 1932). The reliability of estimates obtained with this approach has never been rigorously evaluated using saturated‐unsaturated flow simulation. We present such an evaluation for common flow geometries and a range of hydraulic properties. Results indicate that the major source of error in the White method is the uncertainty in the estimate of specific yield. Evapotranspirative consumption of groundwater will often be significantly overpredicted with the White method if the effects of drainage time and the depth to the water table on specific yield are ignored. We utilize the concept of readily available specific yield as the basis for estimation of the specific yield value appropriate for use with the White method. Guidelines are defined for estimating readily available specific yield based on sediment texture. Use of these guidelines with the White method should enable the evapotranspirative consumption of groundwater to be more accurately quantified.

  4. A New Method for Generating Probability Tables in the Unresolved Resonance Region

    DOE PAGES

    Holcomb, Andrew M.; Leal, Luiz C.; Rahnema, Farzad; ...

    2017-04-18

    One new method for constructing probability tables in the unresolved resonance region (URR) has been developed. This new methodology is an extensive modification of the single-level Breit-Wigner (SLBW) pseudo-resonance pair sequence method commonly used to generate probability tables in the URR. The new method uses a Monte Carlo process to generate many pseudo-resonance sequences by first sampling the average resonance parameter data in the URR and then converting the sampled resonance parameters to the more robust R-matrix limited (RML) format. Furthermore, for each sampled set of pseudo-resonance sequences, the temperature-dependent cross sections are reconstructed on a small grid around themore » energy of reference using the Reich-Moore formalism and the Leal-Hwang Doppler broadening methodology. We then use the effective cross sections calculated at the energies of reference to construct probability tables in the URR. The RML cross-section reconstruction algorithm has been rigorously tested for a variety of isotopes, including 16O, 19F, 35Cl, 56Fe, 63Cu, and 65Cu. The new URR method also produced normalized cross-section factor probability tables for 238U that were found to be in agreement with current standards. The modified 238U probability tables were shown to produce results in excellent agreement with several standard benchmarks, including the IEU-MET-FAST-007 (BIG TEN), IEU-MET-FAST-003, and IEU-COMP-FAST-004 benchmarks.« less

  5. Spine surgeon's kinematics during discectomy, part II: operating table height and visualization methods, including microscope.

    PubMed

    Park, Jeong Yoon; Kim, Kyung Hyun; Kuh, Sung Uk; Chin, Dong Kyu; Kim, Keun Su; Cho, Yong Eun

    2014-05-01

    Surgeon spine angle during surgery was studied ergonomically and the kinematics of the surgeon's spine was related with musculoskeletal fatigue and pain. Spine angles varied depending on operation table height and visualization method, and in a previous paper we showed that the use of a loupe and a table height at the midpoint between the umbilicus and the sternum are optimal for reducing musculoskeletal loading. However, no studies have previously included a microscope as a possible visualization method. The objective of this study is to assess differences in surgeon spine angles depending on operating table height and visualization method, including microscope. We enrolled 18 experienced spine surgeons for this study, who each performed a discectomy using a spine surgery simulator. Three different methods were used to visualize the surgical field (naked eye, loupe, microscope) and three different operating table heights (anterior superior iliac spine, umbilicus, the midpoint between the umbilicus and the sternum) were studied. Whole spine angles were compared for three different views during the discectomy simulation: midline, ipsilateral, and contralateral. A 16-camera optoelectronic motion analysis system was used, and 16 markers were placed from the head to the pelvis. Lumbar lordosis, thoracic kyphosis, cervical lordosis, and occipital angle were compared between the different operating table heights and visualization methods as well as a natural standing position. Whole spine angles differed significantly depending on visualization method. All parameters were closer to natural standing values when discectomy was performed with a microscope, and there were no differences between the naked eye and the loupe. Whole spine angles were also found to differ from the natural standing position depending on operating table height, and became closer to natural standing position values as the operating table height increased, independent of the visualization method

  6. Mortality table construction

    NASA Astrophysics Data System (ADS)

    Sutawanir

    2015-12-01

    Mortality tables play important role in actuarial studies such as life annuities, premium determination, premium reserve, valuation pension plan, pension funding. Some known mortality tables are CSO mortality table, Indonesian Mortality Table, Bowers mortality table, Japan Mortality table. For actuary applications some tables are constructed with different environment such as single decrement, double decrement, and multiple decrement. There exist two approaches in mortality table construction : mathematics approach and statistical approach. Distribution model and estimation theory are the statistical concepts that are used in mortality table construction. This article aims to discuss the statistical approach in mortality table construction. The distributional assumptions are uniform death distribution (UDD) and constant force (exponential). Moment estimation and maximum likelihood are used to estimate the mortality parameter. Moment estimation methods are easier to manipulate compared to maximum likelihood estimation (mle). However, the complete mortality data are not used in moment estimation method. Maximum likelihood exploited all available information in mortality estimation. Some mle equations are complicated and solved using numerical methods. The article focus on single decrement estimation using moment and maximum likelihood estimation. Some extension to double decrement will introduced. Simple dataset will be used to illustrated the mortality estimation, and mortality table.

  7. A method to calibrate phase fluctuation in polarization-sensitive swept-source optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Lu, Zenghai; Kasaragod, Deepa K.; Matcher, Stephen J.

    2011-06-01

    A phase fluctuation calibration method is presented for polarization-sensitive swept-source optical coherence tomography (PS-SS-OCT) using continuous polarization modulation. The method consists of the generation of a continuous triggered tone-burst waveform rather than an asynchronous waveform by use of a function generator and the removal of the global phases of the measured Jones matrices by use of matrix normalization. This could remove the use of auxiliary optical components for the phase fluctuation compensation in the system, which reduces the system complexity. Phase fluctuation calibration is necessary to obtain the reference Jones matrix by averaging the measured Jones matrices at sample surfaces. Measurements on an equine tendon sample were made by the PS-SS-OCT system to validate the proposed method.

  8. Filling the gap: using non-invasive geophysical methods to monitor the processes leading to enhanced carbon turnover induced by periodic water table fluctuations

    NASA Astrophysics Data System (ADS)

    Mellage, A.; Pronk, G.; Atekwana, E. A.; Furman, A.; Rezanezhad, F.; Van Cappellen, P.

    2017-12-01

    Subsurface transition environments such as the capillary fringe are characterized by steep gradients in redox conditions. Spatial and temporal variations in electron acceptor and donor availability - driven by hydrological changes - may enhance carbon turnover, in some cases resulting in pulses of CO2-respiration. Filling the mechanistic knowledge gap between the hydrological driver and its biogeochemical effects hinges on our ability to monitor microbial activity and key geochemical markers at a high spatial and temporal resolution. However, direct access to subsurface biogeochemical processes is logistically difficult, invasive and usually expensive. In-line, non-invasive geophysical techniques - Spectral Induced Polarization (SIP) and Electrodic Potential (EP), specifically - offer a comparatively inexpensive alternative and can provide data with high spatial and temporal resolution. The challenge lies in linking electrical responses to specific changes in biogeochemical processes. We conducted SIP and EP measurements on a soil column experiment where an artificial soil mixture was subjected to monthly drainage and imbibition cycles. SIP responses showed a clear dependence on redox zonation and microbial abundance. Temporally variable responses exhibited no direct moisture dependence suggesting that the measured responses recorded changes in microbial activity and coincided with the depth interval over which enhanced carbon turnover was observed. EP measurements detected the onset of sulfate mineralization and mapped its depth zonation. SIP and EP signals thus detected enhanced microbial activity within the water table fluctuation zone as well as the timing of the development of specific reactive processes. These findings can be used to relate measured electrical signals to specific reaction pathways and help inform reactive transport models, increasing their predictive capabilities.

  9. Methods to predict seasonal high water table (SHGWT) : final report.

    DOT National Transportation Integrated Search

    2017-04-03

    The research study was sectioned into 5 separate tasks. Task 1 included defining the seasonal high ground water table (SHGWT); describing : methods and techniques used to determine SHGWTs; identify problems associated with estimating SHGWT conditions...

  10. Diameter growth and phenology of trees on sites with high water tables

    Treesearch

    D.C. McClurkin

    1965-01-01

    On a site where the water table always was within the root zone, thinning had little effect on diameter growth of white ash or sweetgum but increased the growth of baldcypress. Thinning did not extend durating of growth into the fall, nor was growth related to seasonal fluctuations in the water table. In ash and sweetgum, growth initiation seemed related to soil...

  11. Method to measure efficiently rare fluctuations of turbulence intensity for turbulent-laminar transitions in pipe flows

    NASA Astrophysics Data System (ADS)

    Nemoto, Takahiro; Alexakis, Alexandros

    2018-02-01

    The fluctuations of turbulence intensity in a pipe flow around the critical Reynolds number is difficult to study but important because they are related to turbulent-laminar transitions. We here propose a rare-event sampling method to study such fluctuations in order to measure the time scale of the transition efficiently. The method is composed of two parts: (i) the measurement of typical fluctuations (the bulk part of an accumulative probability function) and (ii) the measurement of rare fluctuations (the tail part of the probability function) by employing dynamics where a feedback control of the Reynolds number is implemented. We apply this method to a chaotic model of turbulent puffs proposed by Barkley and confirm that the time scale of turbulence decay increases super exponentially even for high Reynolds numbers up to Re =2500 , where getting enough statistics by brute-force calculations is difficult. The method uses a simple procedure of changing Reynolds number that can be applied even to experiments.

  12. Diagnostic articulation tables

    NASA Astrophysics Data System (ADS)

    Mikhailov, V. G.

    2002-09-01

    In recent years, considerable progress has been made in the development of instrumental methods for general speech quality and intelligibility evaluation on the basis of modeling the auditory perception of speech and measuring the signal-to-noise ratio. Despite certain advantages (fast measurement procedures with a low labor consumption), these methods are not universal and, in essence, secondary, because they rely on the calibration based on subjective-statistical measurements. At the same time, some specific problems of speech quality evaluation, such as the diagnostics of the factors responsible for the deviation of the speech quality from standard (e.g., accent features of a speaker or individual voice distortions), can be solved by psycholinguistic methods. This paper considers different kinds of diagnostic articulation tables: tables of minimal pairs of monosyllabic words (DRT) based on the Jacobson differential features, tables consisting of multisyllabic quartets of Russian words (the choice method), and tables of incomplete monosyllables of the _VC/CV_ type (the supplementary note method). Comparative estimates of the tables are presented along with the recommendations concerning their application.

  13. A Fuzzy-Based Control Method for Smoothing Power Fluctuations in Substations along High-Speed Railways

    NASA Astrophysics Data System (ADS)

    Sugio, Tetsuya; Yamamoto, Masayoshi; Funabiki, Shigeyuki

    The use of an SMES (Superconducting Magnetic Energy Storage) for smoothing power fluctuations in a railway substation has been discussed. This paper proposes a smoothing control method based on fuzzy reasoning for reducing the SMES capacity at substations along high-speed railways. The proposed smoothing control method comprises three countermeasures for reduction of the SMES capacity. The first countermeasure involves modification of rule 1 for smoothing out the fluctuating electric power to its average value. The other countermeasures involve the modification of the central value of the stored energy control in the SMES and revision of the membership function in rule 2 for reduction of the SMES capacity. The SMES capacity in the proposed smoothing control method is reduced by 49.5% when compared to that in the nonrevised control method. It is confirmed by computer simulations that the proposed control method is suitable for smoothing out power fluctuations in substations along high-speed railways and for reducing the SMES capacity.

  14. Relationships between water table and model simulated ET

    Treesearch

    Prem B. Parajuli; Gretchen F. Sassenrath; Ying Ouyang

    2013-01-01

    This research was conducted to develop relationships among evapotranspiration (ET), percolation (PERC), groundwater discharge to the stream (GWQ), and water table fluctuations through a modeling approach. The Soil and Water Assessment Tool (SWAT) hydrologic and crop models were applied in the Big Sunflower River watershed (BSRW; 7660 km2) within the Yazoo River Basin...

  15. Energy Requirement Assessment in Japanese Table Tennis Players Using the Doubly Labeled Water Method.

    PubMed

    Sagayama, Hiroyuki; Hamaguchi, Genki; Toguchi, Makiko; Ichikawa, Mamiko; Yamada, Yosuke; Ebine, Naoyuki; Higaki, Yasuki; Tanaka, Hiroaki

    2017-10-01

    Total daily energy expenditure (TEE) and physical activity level (PAL) are important for adequate nutritional management in athletes. The PAL of table tennis has been estimated to about 2.0: it is categorized as a moderateactivity sport (4.0 metabolic equivalents [METs]) in the Compendium of Physical Activities. However, modern table tennis makes high physiological demands. The aims of the current study were to examine (1) TEE and PAL of competitive table tennis players and (2) the physiological demands of various types of table tennis practice. In Experiment 1, we measured TEE and PAL in 10 Japanese college competitive table tennis players (aged 19.9 ± 1.1 years) using the doubly labeled water (DLW) method during training and with an exercise training log and self-reported energy intake. TEE was 15.5 ± 1.9 MJ·day -1 (3695 ± 449 kcal·day -1 ); PAL was 2.53 ± 0.25; and the average training duration was 181 ± 38 min·day -1 . In Experiment 2, we measured METs of five different practices in seven college competition players (20.6 ± 1.2 years). Three practices without footwork were 4.5-5.2 METs, and two practices with footwork were 9.5-11.5 METs. Table tennis practices averaged 7.1 ± 3.2 METS demonstrating similarities with other vigorous racket sports. In conclusion the current Compendium of Physical Activities underestimates the physiological demands of table tennis practice for competition; the estimated energy requirement should be based on DLW method data.

  16. Scots pine (Pinus sylvestris L.) based reconstruction of 130 years of water table fluctuations in a peatland and its relevance for moisture variability assessments

    NASA Astrophysics Data System (ADS)

    Tamkevičiūtė, Marija; Edvardsson, Johannes; Pukienė, Rūtilė; Taminskas, Julius; Stoffel, Markus; Corona, Christophe; Kibirkštis, Gintautas

    2018-03-01

    Continuous water-table (WT) measurements from peatlands are scarce and - if existing at all -very short. Consequently, proxy indicators are critically needed to simulate hydrological changes in peatlands over longer time periods. In this study, we demonstrate that tree-ring width (TRW) records of Scots pine (Pinus sylvestris L.) growing in the Čepkeliai peatland (southern Lithuania) can be used as a proxy to reconstruct hydrological variability in a raised bog environment. A two-step modelling procedure was applied to extend existing measurements and to develop a new and longer peatland WT time series. To this end, we used instrumental WT measurements extending back to 2002, meteorological records, a P-PET (difference between precipitation and potential evapotranspiration) series covering the period 1935-2014, so as to construct a tree-ring based time series of WT fluctuations at the site for the period 1870-2014. Strongest correlations were obtained between average annual WT measured at the bog margin and total P-PET over 7 years (r = 0.923, p < 0.00001), as well as between modelled WT and standardized TRW data with a two years lag (r = -0.602, p < 0.001) for those periods where WT fluctuated at the level of pine roots which is typically at <50 cm depth below the peat surface. Our results suggest that moisture is a limiting factor for tree growth at peatlands, but below a certain WT level (<50 cm under the soil surface), drought becomes a limiting factor instead. To validate the WT reconstruction from the Čepkeliai bog, results were compared to Nemunas river runoff since CE 1812 (r = 0.39, p < 0.00001, 1870-2014). We conclude that peatlands can act both as sinks and sources of greenhouse gases in case that hydrological conditions change, but that hydrological lags and complex feedbacks still hamper our understanding of several processes affecting the hydrology and carbon budget in peatlands. We therefore call for the development of further proxy records of water-table

  17. Symbol Tables and Branch Tables: Linking Applications Together

    NASA Technical Reports Server (NTRS)

    Handler, Louis M.

    2011-01-01

    This document explores the computer techniques used to execute software whose parts are compiled and linked separately. The computer techniques include using a branch table or indirect address table to connect the parts. Methods of storing the information in data structures are discussed as well as differences between C and C++.

  18. Image compression system and method having optimized quantization tables

    NASA Technical Reports Server (NTRS)

    Ratnakar, Viresh (Inventor); Livny, Miron (Inventor)

    1998-01-01

    A digital image compression preprocessor for use in a discrete cosine transform-based digital image compression device is provided. The preprocessor includes a gathering mechanism for determining discrete cosine transform statistics from input digital image data. A computing mechanism is operatively coupled to the gathering mechanism to calculate a image distortion array and a rate of image compression array based upon the discrete cosine transform statistics for each possible quantization value. A dynamic programming mechanism is operatively coupled to the computing mechanism to optimize the rate of image compression array against the image distortion array such that a rate-distortion-optimal quantization table is derived. In addition, a discrete cosine transform-based digital image compression device and a discrete cosine transform-based digital image compression and decompression system are provided. Also, a method for generating a rate-distortion-optimal quantization table, using discrete cosine transform-based digital image compression, and operating a discrete cosine transform-based digital image compression and decompression system are provided.

  19. Influence of thermal fluctuations on ligament break-up: a fluctuating lattice Boltzmann study

    NASA Astrophysics Data System (ADS)

    Xue, Xiao; Biferale, Luca; Sbragaglia, Mauro; Toschi, Federico

    2017-11-01

    Thermal fluctuations are essential ingredients in a nanoscale system, driving Brownian motion of particles and capillary waves at non-ideal interfaces. Here we study the influence of thermal fluctuations on the breakup of liquid ligaments at the nanoscale. We offer quantitative characterization of the effects of thermal fluctuations on the Plateau-Rayleigh mechanism that drives the breakup process of ligaments. Due to thermal fluctuations, the droplet sizes after break-up need to be analyzed in terms of their distribution over an ensemble made of repeated experiments. To this aim, we make use of numerical simulations based on the fluctuating lattice Boltzmann method (FLBM) for multicomponent mixtures. The method allows an accurate and efficient simulation of the fluctuating hydrodynamics equations of a binary mixture, where both stochastic viscous stresses and diffusion fluxes are introduced. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No 642069.

  20. An Effective Method of Introducing the Periodic Table as a Crossword Puzzle at the High School Level

    ERIC Educational Resources Information Center

    Joag, Sushama D.

    2014-01-01

    A simple method to introduce the modern periodic table of elements at the high school level as a game of solving a crossword puzzle is presented here. A survey to test the effectiveness of this new method relative to the conventional method, involving use of a wall-mounted chart of the periodic table, was conducted on a convenience sample. This…

  1. 40 CFR Table C-3 to Subpart C of... - Test Specifications for Pb in TSP and Pb in PM10 Methods

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Pb in PM10 Methods C Table C-3 to Subpart C of Part 53 Protection of Environment ENVIRONMENTAL..., Subpt. C, Table C-3 Table C-3 to Subpart C of Part 53—Test Specifications for Pb in TSP and Pb in PM10 Methods Table C-3 to Subpart C of Part 53—Test Specifications for Pb in TSP and Pb in PM10 Methods...

  2. 40 CFR Table C-3 to Subpart C of... - Test Specifications for Pb in TSP and Pb in PM10 Methods

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Pb in PM10 Methods C Table C-3 to Subpart C of Part 53 Protection of Environment ENVIRONMENTAL..., Subpt. C, Table C-3 Table C-3 to Subpart C of Part 53—Test Specifications for Pb in TSP and Pb in PM10 Methods Table C-3 to Subpart C of Part 53—Test Specifications for Pb in TSP and Pb in PM10 Methods...

  3. Fluctuating local field method probed for a description of small classical correlated lattices

    NASA Astrophysics Data System (ADS)

    Rubtsov, Alexey N.

    2018-05-01

    Thermal-equilibrated finite classical lattices are considered as a minimal model of the systems showing an interplay between low-energy collective fluctuations and single-site degrees of freedom. Standard local field approach, as well as classical limit of the bosonic DMFT method, do not provide a satisfactory description of Ising and Heisenberg small lattices subjected to an external polarizing field. We show that a dramatic improvement can be achieved within a simple approach, in which the local field appears to be a fluctuating quantity related to the low-energy degree(s) of freedom.

  4. Identity method for particle number fluctuations and correlations

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

    Gorenstein, M. I.

    An incomplete particle identification distorts the observed event-by-event fluctuations of the hadron chemical composition in nucleus-nucleus collisions. A new experimental technique called the identity method was recently proposed. It eliminated the misidentification problem for one specific combination of the second moments in a system of two hadron species. In the present paper, this method is extended to calculate all the second moments in a system with an arbitrary number of hadron species. Special linear combinations of the second moments are introduced. These combinations are presented in terms of single-particle variables and can be found experimentally from the event-by-event averaging. Themore » mathematical problem is then reduced to solving a system of linear equations. The effect of incomplete particle identification is fully eliminated from the final results.« less

  5. Cervical spine motion in manual versus Jackson table turning methods in a cadaveric global instability model.

    PubMed

    DiPaola, Matthew J; DiPaola, Christian P; Conrad, Bryan P; Horodyski, MaryBeth; Del Rossi, Gianluca; Sawers, Andrew; Bloch, David; Rechtine, Glenn R

    2008-06-01

    A study of spine biomechanics in a cadaver model. To quantify motion in multiple axes created by transfer methods from stretcher to operating table in the prone position in a cervical global instability model. Patients with an unstable cervical spine remain at high risk for further secondary injury until their spine is adequately surgically stabilized. Previous studies have revealed that collars have significant, but limited benefit in preventing cervical motion when manually transferring patients. The literature proposes multiple methods of patient transfer, although no one method has been universally adopted. To date, no study has effectively evaluated the relationship between spine motion and various patient transfer methods to an operating room table for prone positioning. A global instability was surgically created at C5-6 in 4 fresh cadavers with no history of spine pathology. All cadavers were tested both with and without a rigid cervical collar in the intact and unstable state. Three headrest permutations were evaluated Mayfield (SM USA Inc), Prone View (Dupaco, Oceanside, CA), and Foam Pillow (OSI, Union City, CA). A trained group of medical staff performed each of 2 transfer methods: the "manual" and the "Jackson table" transfer. The manual technique entailed performing a standard rotation of the supine patient on a stretcher to the prone position on the operating room table with in-line manual cervical stabilization. The "Jackson" technique involved sliding the supine patient to the Jackson table (OSI, Union City, CA) with manual in-line cervical stabilization, securing them to the table, then initiating the table's lock and turn mechanism and rotating them into a prone position. An electromagnetic tracking device captured angular motion between the C5 and C6 vertebral segments. Repeated measures statistical analysis was performed to evaluate the following conditions: collar use (2 levels), headrest (3 levels), and turning technique (2 levels). For all

  6. Helium tables.

    NASA Technical Reports Server (NTRS)

    Havill, Clinton H

    1928-01-01

    These tables are intended to provide a standard method and to facilitate the calculation of the quantity of "Standard Helium" in high pressure containers. The research data and the formulas used in the preparation of the tables were furnished by the Research Laboratory of Physical Chemistry, of the Massachusetts Institute of Technology.

  7. Evaluation of the table Mountain Ronchi telescope for angular tracking

    NASA Technical Reports Server (NTRS)

    Lanyi, G.; Purcell, G.; Treuhaft, R.; Buffington, A.

    1992-01-01

    The performance of the University of California at San Diego (UCSD) Table Mountain telescope was evaluated to determine the potential of such an instrument for optical angular tracking. This telescope uses a Ronchi ruling to measure differential positions of stars at the meridian. The Ronchi technique is summarized and the operational features of the Table Mountain instrument are described. Results from an analytic model, simulations, and actual data are presented that characterize the telescope's current performance. For a star pair of visual magnitude 7, the differential uncertainty of a 5-min observation is about 50 nrad (10 marcsec), and tropospheric fluctuations are the dominant error source. At magnitude 11, the current differential uncertainty is approximately 800 nrad (approximately 170 marcsec). This magnitude is equivalent to that of a 2-W laser with a 0.4-m aperture transmitting to Earth from a spacecraft at Saturn. Photoelectron noise is the dominant error source for stars of visual magnitude 8.5 and fainter. If the photoelectron noise is reduced, ultimately tropospheric fluctuations will be the limiting source of error at an average level of 35 nrad (7 marcsec) for stars approximately 0.25 deg apart. Three near-term strategies are proposed for improving the performance of the telescope to the 10-nrad level: improving the efficiency of the optics, masking background starlight, and averaging tropospheric fluctuations over multiple observations.

  8. Predicting groundwater level fluctuations with meteorological effect implications—A comparative study among soft computing techniques

    NASA Astrophysics Data System (ADS)

    Shiri, Jalal; Kisi, Ozgur; Yoon, Heesung; Lee, Kang-Kun; Hossein Nazemi, Amir

    2013-07-01

    The knowledge of groundwater table fluctuations is important in agricultural lands as well as in the studies related to groundwater utilization and management levels. This paper investigates the abilities of Gene Expression Programming (GEP), Adaptive Neuro-Fuzzy Inference System (ANFIS), Artificial Neural Networks (ANN) and Support Vector Machine (SVM) techniques for groundwater level forecasting in following day up to 7-day prediction intervals. Several input combinations comprising water table level, rainfall and evapotranspiration values from Hongcheon Well station (South Korea), covering a period of eight years (2001-2008) were used to develop and test the applied models. The data from the first six years were used for developing (training) the applied models and the last two years data were reserved for testing. A comparison was also made between the forecasts provided by these models and the Auto-Regressive Moving Average (ARMA) technique. Based on the comparisons, it was found that the GEP models could be employed successfully in forecasting water table level fluctuations up to 7 days beyond data records.

  9. Effects of soil water table regime on tree community species richness and structure of alluvial forest fragments in Southeast Brazil.

    PubMed

    Silva, A C; Higuchi, P; van den Berg, E

    2010-08-01

    In order to determine the influence of soil water table fluctuation on tree species richness and structure of alluvial forest fragments, 24 plots were allocated in a point bar forest and 30 plots in five forest fragments located in a floodplain, in the municipality of São Sebastião da Bela Vista, Southeast Brazil, totalizing 54, 10 X 20 m, plots. The information recorded in each plot were the soil water table level, diameter at breast height (dbh), total height and botanical identity off all trees with dbh > 5 cm. The water table fluctuation was assessed through 1 m deep observation wells in each plot. Correlations analysis indicated that sites with shallower water table in the flooding plains had a low number of tree species and high tree density. Although the water table in the point bar remained below the wells during the study period, low tree species richness was observed. There are other events taking place within the point bar forest that assume a high ecological importance, such as the intensive water velocity during flooding and sedimentation processes.

  10. Integer lattice gas with Monte Carlo collision operator recovers the lattice Boltzmann method with Poisson-distributed fluctuations

    NASA Astrophysics Data System (ADS)

    Blommel, Thomas; Wagner, Alexander J.

    2018-02-01

    We examine a new kind of lattice gas that closely resembles modern lattice Boltzmann methods. This new kind of lattice gas, which we call a Monte Carlo lattice gas, has interesting properties that shed light on the origin of the multirelaxation time collision operator, and it derives the equilibrium distribution for an entropic lattice Boltzmann. Furthermore these lattice gas methods have Galilean invariant fluctuations given by a Poisson statistics, giving further insight into the properties that we should expect for fluctuating lattice Boltzmann methods.

  11. Life-table methods for detecting age-risk factor interactions in long-term follow-up studies.

    PubMed

    Logue, E E; Wing, S

    1986-01-01

    Methodological investigation has suggested that age-risk factor interactions should be more evident in age of experience life tables than in follow-up time tables due to the mixing of ages of experience over follow-up time in groups defined by age at initial examination. To illustrate the two approaches, age modification of the effect of total cholesterol on ischemic heart disease mortality in two long-term follow-up studies was investigated. Follow-up time life table analysis of 116 deaths over 20 years in one study was more consistent with a uniform relative risk due to cholesterol, while age of experience life table analysis was more consistent with a monotonic negative age interaction. In a second follow-up study (160 deaths over 24 years), there was no evidence of a monotonic negative age-cholesterol interaction by either method. It was concluded that age-specific life table analysis should be used when age-risk factor interactions are considered, but that both approaches yield almost identical results in absence of age interaction. The identification of the more appropriate life-table analysis should be ultimately guided by the nature of the age or time phenomena of scientific interest.

  12. A study on the influence of tides on the water table conditions of the shallow coastal aquifers

    NASA Astrophysics Data System (ADS)

    Singaraja, C.; Chidambaram, S.; Jacob, Noble

    2018-03-01

    Tidal variation and water level in aquifer is an important function in the coastal environment, this study attempts to find the relationship between water table fluctuation and tides in the shallow coastal aquifers. The study was conducted by selecting three coastal sites and by monitoring the water level for every 2-h interval in 24 h of observation. The study was done during two periods of full moon and new moon along the Cuddalore coastal region of southern part of Tamil Nadu, India. The study shows the relationship between tidal variation, water table fluctuations, dissolved oxygen, and electrical conductivity. An attempt has also been made in this study to approximate the rate of flow of water. Anyhow, the differences are site specific and the angle of inclination of the water table shows a significant relation to the mean sea level, with respect to the distance of the point of observation from the sea and elevation above mean sea level.

  13. Life History Characteristics of Frankliniella occidentalis and Frankliniella intonsa (Thysanoptera: Thripidae) in Constant and Fluctuating Temperatures.

    PubMed

    Ullah, Mohammad Shaef; Lim, Un Taek

    2015-06-01

    Frankliniella occidentalis (Pergande) and Frankliniella intonsa (Trybom) are sympatric pests of many greenhouse and field crops in Korea. We compared the influence of constant (27.3°C) and fluctuating temperatures (23.8-31.5°C, with an average of 27.3°C) on the life table characteristics of F. occidentalis and F. intonsa held at a photoperiod of 16:8 (L:D) h and 45±5% relative humidity. The development times of both F. occidentalis and F. intonsa were significantly affected by temperature fluctuation, species, and sex. The development time from egg to adult of F. intonsa was shorter than that for F. occidentalis at both constant and fluctuating temperatures. Survival of immature life stages was higher under fluctuating than constant temperature for both thrips species. The total and daily production of first instars was higher in F. intonsa (90.4 and 4.2 at constant temperature, and 95.7 and 3.9 at fluctuating temperatures) than that of F. occidentalis (58.7 and 3.3 at constant temperature, and 60.5 and 3.1 at fluctuating temperatures) under both constant and fluctuating temperatures. The percentage of female offspring was greater in F. intonsa (72.1-75.7%) than in F. occidentalis (57.4-58.7%) under both temperature regimes. The intrinsic rate of natural increase (rm) was higher at constant temperature than at fluctuating temperature for both thrips species. F. intonsa had a higher rm value (0.2146 and 0.2004) than did F. occidentalis (0.1808 and 0.1733), under both constant and fluctuating temperatures, respectively. The biological response of F. occidentalis and F. intonsa to constant and fluctuating temperature was found to be interspecifically different, and F. intonsa may have higher pest potential than F. occidentalis based on the life table parameters we are reporting first here. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Increasing the utility of regional water table maps: a new method for estimating groundwater recharge

    NASA Astrophysics Data System (ADS)

    Gilmore, T. E.; Zlotnik, V. A.; Johnson, M.

    2017-12-01

    Groundwater table elevations are one of the most fundamental measurements used to characterize unconfined aquifers, groundwater flow patterns, and aquifer sustainability over time. In this study, we developed an analytical model that relies on analysis of groundwater elevation contour (equipotential) shape, aquifer transmissivity, and streambed gradient between two parallel, perennial streams. Using two existing regional water table maps, created at different times using different methods, our analysis of groundwater elevation contours, transmissivity and streambed gradient produced groundwater recharge rates (42-218 mm yr-1) that were consistent with previous independent recharge estimates from different methods. The three regions we investigated overly the High Plains Aquifer in Nebraska and included some areas where groundwater is used for irrigation. The three regions ranged from 1,500 to 3,300 km2, with either Sand Hills surficial geology, or Sand Hills transitioning to loess. Based on our results, the approach may be used to increase the value of existing water table maps, and may be useful as a diagnostic tool to evaluate the quality of groundwater table maps, identify areas in need of detailed aquifer characterization and expansion of groundwater monitoring networks, and/or as a first approximation before investing in more complex approaches to groundwater recharge estimation.

  15. A novel method linking neural connectivity to behavioral fluctuations: Behavior-regressed connectivity.

    PubMed

    Passaro, Antony D; Vettel, Jean M; McDaniel, Jonathan; Lawhern, Vernon; Franaszczuk, Piotr J; Gordon, Stephen M

    2017-03-01

    During an experimental session, behavioral performance fluctuates, yet most neuroimaging analyses of functional connectivity derive a single connectivity pattern. These conventional connectivity approaches assume that since the underlying behavior of the task remains constant, the connectivity pattern is also constant. We introduce a novel method, behavior-regressed connectivity (BRC), to directly examine behavioral fluctuations within an experimental session and capture their relationship to changes in functional connectivity. This method employs the weighted phase lag index (WPLI) applied to a window of trials with a weighting function. Using two datasets, the BRC results are compared to conventional connectivity results during two time windows: the one second before stimulus onset to identify predictive relationships, and the one second after onset to capture task-dependent relationships. In both tasks, we replicate the expected results for the conventional connectivity analysis, and extend our understanding of the brain-behavior relationship using the BRC analysis, demonstrating subject-specific BRC maps that correspond to both positive and negative relationships with behavior. Comparison with Existing Method(s): Conventional connectivity analyses assume a consistent relationship between behaviors and functional connectivity, but the BRC method examines performance variability within an experimental session to understand dynamic connectivity and transient behavior. The BRC approach examines connectivity as it covaries with behavior to complement the knowledge of underlying neural activity derived from conventional connectivity analyses. Within this framework, BRC may be implemented for the purpose of understanding performance variability both within and between participants. Published by Elsevier B.V.

  16. Field observation of diurnal dissolved oxygen fluctuations in shallow groundwater.

    PubMed

    Schilling, Keith E; Jacobson, Peter

    2015-01-01

    Dissolved oxygen (DO) concentrations influence many biogeochemical processes in groundwater systems but studies of temporal variability in DO are lacking. In this study, we used an optical DO probe to measure rapid changes in concentration due to plant-groundwater interaction at an alluvial aquifer field site in Iowa. Diurnal DO concentrations were observed during mid- to late-summer when soil conditions were dry, fluctuating approximately 0.2 to 0.3 mg/L on a daily basis. DO fluctuations in groundwater were out-of-phase with diurnal water table fluctuations, increasing during the day and decreasing at night. DO consumption at night is likely due to increased soil autotrophic and heterotrophic respiration linked with patterns of carbon supply derived from daytime photosynthetic activity, and consistent with available literature on diurnal soil respiration patterns. Although more work is needed to quantify specific processes, our results indicate the potential usefulness of the new optical DO technology to reveal insights regarding many ecohydrological processes. © 2014, National Ground Water Association.

  17. Development of insect life tables: comparison of two demographic methods of Delia antiqua (Diptera: Anthomyiidae) on different hosts.

    PubMed

    Ning, Shuoying; Zhang, Wenchao; Sun, Yan; Feng, Jinian

    2017-07-06

    In this study, we first construct an age-stage, two-sex life table for onion maggot, Delia antiqua, grown on three host plants: onion, scallion, and garlic. We found that onion is the optimal host for this species and populations grown on onion have maximum fecundity, longest adult longevity and reproduction period, and the shortest immature developmental time. In contrast, the fecundity on other hosts was lower, particularly on garlic, but these crops can also serve as important secondary hosts for this pest. These data will be useful to the growers to develop specific integrated management programs for each of hosts. We also compared the demographic analyses of using individually-reared and group-reared methods. These two methods provided similar accurate outcomes for estimating insect population dynamics for this species. However, for gregarious species, using the individually-reared method to construct insect life tables produces inaccurate results, and researchers must use group-reared method for life table calculations. When studying large groups of insect, group-reared demographic analysis for age-stage, two-sex life table can also simplify statistical analysis, save considerable labor, and reduce experimental errors.

  18. Towards "Inverse" Character Tables? A One-Step Method for Decomposing Reducible Representations

    ERIC Educational Resources Information Center

    Piquemal, J.-Y.; Losno, R.; Ancian, B.

    2009-01-01

    In the framework of group theory, a new procedure is described for a one-step automated reduction of reducible representations. The matrix inversion tool, provided by standard spreadsheet software, is applied to the central part of the character table that contains the characters of the irreducible representation. This method is not restricted to…

  19. [A method to estimate one's own blood alcohol concentration when the ministerial tables are not avaible].

    PubMed

    Dosi, G; Taggi, F; Macchia, T

    2009-01-01

    To reduce the prevalence of driving under the influence, tables allowing to estimate one's own blood alcohol concentration (BAC) by type and quantity of alcoholic drinks intake have been enacted by decree in Italy. Such tables, based on a modified Widmark's formula, are now put up in all public concerns serving alcoholic beverages. Aim of this initiative is to try to get subjects which consume alcoholics and then will drive a vehicle take in account their own estimated BAC and, on this base, put into effect, if needed, suitable actions (to avoid or to limit a further consumption, to wait more time before driving, to leave driving a sober subject). Nevertheless, many occasions exist in which these tables are not available. To allow anybody to rough estimate his own BAC in these cases too, a proper method has been developed. Briefly, the weight (in grams) of consumed alcohol has to be divided by half her own weight, if female drunk on an empty stomach (by the 90% of her own weight, if she drunk on a full stomach); by 70% of his own weight, if male drunk on an empty stomach (by 120% of his own weight, if he drunk in a full stomach). Consistency between BAC values estimated by the proposed method and those shown in the ministerial tables is very narrow: they differ in a few hundredth of grams/liter. Unlike the ministerial tables, the proposed method needs to compute the grams of ingested alcohol. This maybe involves some difficulties that, nevertheless, can be overcome easily. In our opinion, the skillfulness in computing the grams of assumed alcohol is of great significance since it provides the subject with a strong signal not only in road safety terms, but also in health terms. The ministerial tables and the proposed method should be part of teaching to issue the driving licence and to recovery of driving licence taken away points. In broad terms, the school should teach youngs to calculate alcohol quantities assumed by drink to acquaint them with the risks paving

  20. Quantifying fluctuations in economic systems by adapting methods of statistical physics

    NASA Astrophysics Data System (ADS)

    Stanley, H. E.; Gopikrishnan, P.; Plerou, V.; Amaral, L. A. N.

    2000-12-01

    The emerging subfield of econophysics explores the degree to which certain concepts and methods from statistical physics can be appropriately modified and adapted to provide new insights into questions that have been the focus of interest in the economics community. Here we give a brief overview of two examples of research topics that are receiving recent attention. A first topic is the characterization of the dynamics of stock price fluctuations. For example, we investigate the relation between trading activity - measured by the number of transactions NΔ t - and the price change GΔ t for a given stock, over a time interval [t, t+ Δt] . We relate the time-dependent standard deviation of price fluctuations - volatility - to two microscopic quantities: the number of transactions NΔ t in Δ t and the variance WΔ t2 of the price changes for all transactions in Δ t. Our work indicates that while the pronounced tails in the distribution of price fluctuations arise from WΔ t, the long-range correlations found in ∣ GΔ t∣ are largely due to NΔ t. We also investigate the relation between price fluctuations and the number of shares QΔ t traded in Δ t. We find that the distribution of QΔ t is consistent with a stable Lévy distribution, suggesting a Lévy scaling relationship between QΔ t and NΔ t, which would provide one explanation for volume-volatility co-movement. A second topic concerns cross-correlations between the price fluctuations of different stocks. We adapt a conceptual framework, random matrix theory (RMT), first used in physics to interpret statistical properties of nuclear energy spectra. RMT makes predictions for the statistical properties of matrices that are universal, that is, do not depend on the interactions between the elements comprising the system. In physics systems, deviations from the predictions of RMT provide clues regarding the mechanisms controlling the dynamics of a given system, so this framework can be of potential value if

  1. Comparison of risk estimates using life-table methods.

    PubMed

    Sullivan, R E; Weng, P S

    1987-08-01

    Risk estimates promulgated by various radiation protection authorities in recent years have become increasingly more complex. Early "integral" estimates in the form of health effects per 0.01 person-Gy (per person-rad) or per 10(4) person-Gy (per 10(6) person-rad) have tended to be replaced by "differential" estimates which are age- and sex-dependent and specify both minimum induction (latency) and duration of risk expression (plateau) periods. These latter types of risk estimate must be used in conjunction with a life table in order to reduce them to integral form. In this paper, the life table has been used to effect a comparison of the organ and tissue risk estimates derived in several recent reports. In addition, a brief review of life-table methodology is presented and some features of the models used in deriving differential coefficients are discussed. While the great number of permutations possible with dose-response models, detailed risk estimates and proposed projection models precludes any unique result, the reduced integral coefficients are required to conform to the linear, absolute-risk model recommended for use with the integral risk estimates reviewed.

  2. Analysis of underlying and multiple-cause mortality data: the life table methods.

    PubMed

    Moussa, M A

    1987-02-01

    The stochastic compartment model concepts are employed to analyse and construct complete and abbreviated total mortality life tables, multiple-decrement life tables for a disease, under the underlying and pattern-of-failure definitions of mortality risk, cause-elimination life tables, cause-elimination effects on saved population through the gain in life expectancy as a consequence of eliminating the mortality risk, cause-delay life tables designed to translate the clinically observed increase in survival time as the population gain in life expectancy that would occur if a treatment protocol was made available to the general population and life tables for disease dependency in multiple-cause data.

  3. Fluctuation traits of Litchi wholesale price in China

    NASA Astrophysics Data System (ADS)

    Yan, F. F.; Qi, W. E.; Ouyang, X.

    2017-07-01

    This paper chose the wholesale price of litchi as research object based on the daily data of 11 main sales markets in China -- Beijing, Chengdu, Guangzhou, Hefei, Jiaxing, Nanjing, Shanghai, Shenyang, Changsha, Zhengzhou and Chongqing from April 1, 2012 to September 30, 2016. After analyzing the fluctuation characteristics with BP filter method and H-P filter method, and the fluctuation trends of litchi wholesale price in China obtained by BP filter are roughly consistent with the trends obtained by H-P filter. The main conclusions are as follows: there is strong cyclicality in the fluctuation of litchi wholesale price; the period of fluctuations of litchi wholesale prices are not repeatable; litchi wholesale price fluctuates asymmetrically in one fluctuation cycle.

  4. Preliminary Analysis of Fluctuations in the Received Uplink-Beacon-Power Data Obtained From the GOLD Experiments

    NASA Technical Reports Server (NTRS)

    Jeganathan, M.; Wilson, K. E.; Lesh, J. R.

    1996-01-01

    Uplink data from recent free-space optical communication experiments carried out between the Table Mountain Facility and the Japanese Engineering Test Satellite are used to study fluctuations caused by beam propagation through the atmosphere. The influence of atmospheric scintillation, beam wander and jitter, and multiple uplink beams on the statistics of power received by the satellite is analyzed and compared to experimental data. Preliminary analysis indicates the received signal obeys an approximate lognormal distribution, as predicted by the weak-turbulence model, but further characterization of other sources of fluctuations is necessary for accurate link predictions.

  5. Preliminary analysis of fluctuations in the received uplink-beacon-power data obtained from the GOLD experiments

    NASA Technical Reports Server (NTRS)

    Jeganathan, M.; Wilson, K. E.; Lesh, J. R.

    1996-01-01

    Uplink data from recent free-space optical communication experiments carried out between the Table Mountain Facility and the Japanese Engineering Test Satellite are used to study fluctuations caused by beam propagation through the atmosphere. The influence of atmospheric scintillation, beam wander and jitter, and multiple uplink beams on the statistics of power received by the satellite is analyzed and compared to experimental data. Preliminary analysis indicates the received signal obeys an approximate lognormal distribution, as predicted by the weak-turbulence model, but further characterization of other sources of fluctuations is necessary for accurate link predictions.

  6. Interactive data based on Apriori - AHP - C4.5 results assessment method

    NASA Astrophysics Data System (ADS)

    Zhao, Quan; Zhang, Li

    2017-05-01

    AHP method for weight calculation method, will introduce the subjective concept of "experts, supposed steps", for the objective result has certain uncertainty, causes the classroom interaction data attribute weights proportion difference is not big, the whole class achievement trend of convergence, introduce the concept of Apriori-AHP. C4.5 is used to calculate the weight of attribute column, and then using the Apriori-AHP algorithm calculate attribute weights, attribute importance weights on judgment performance indicators table overall consideration, with the weight of index table of gifted student achievement, make the class performance trends to fluctuate, have tended to be "standard" real results for teacher reference.

  7. How well do testate amoebae transfer functions relate to high-resolution water-table records?

    NASA Astrophysics Data System (ADS)

    Holden, Joseph; Swindles, Graeme; Raby, Cassandra; Blundell, Antony

    2014-05-01

    Testate amoebae (TA) community composition records from peat cores are often used to infer past water-table conditions on peatland sites. However, one of the problems is that validation of water-table depths used in such work typically comes from a one-off water-table measurement or a few measurements of water-table depth from the testate amoebae sample extraction point. Furthermore, one value of water-table depth is produced by the transfer function reconstruction, with sample-specific errors generated through a statistical resampling approach. However, we know that water tables fluctuate in peatlands and are dynamic. Traditional TA water-table data may not adequately capture a mean value from a site, and may not account for water-table dynamics (e.g. seasonal or annual variability) that could influence the TA community composition. We analysed automatically logged (at least hourly, mainly 15-min) peatland water-table data from 72 different dipwells located across northern Sweden, Wales and the Pennine region of England. Each location had not been subject to recent management intervention. A suite of characteristics of water-table dynamics for each point were determined. At each point surface samples were extracted and the TA community composition was determined. Our results show that estimated water-table depth based on the TA community transfer functions poorly represents the real mean or median water tables for the study sites. The TA approach does, however, generally identify sites that have water tables that are closer to the surface for a greater proportion of the year compared to sites with deeper water tables for large proportions of the year. However, the traditional TA approach does not differentiate between sites with similar mean (or median) water-table depths yet which have quite different water table variability (e.g. interquartile range). We suggest some ways of improving water-table metrics for use in Holocene peatland hydrology reconstructions.

  8. Beneficiation of Kulon Progo iron sand by using tabling and magnetic separation methods

    NASA Astrophysics Data System (ADS)

    Oediyani, Soesaptri; Ikhlasul Amal, M.; M. Victoriyan, N.; Juniarsih, Andinnie

    2018-04-01

    There are two types of iron resources such as primary iron ore and iron sand. In general, primary iron ores use as raw materials in iron and steel making because the iron content is high (± 60%) and can reduce directly. On the other and, iron sand is rarely used as a raw material because the iron content is low (20-40%) but the iron sand reserves are very abundant in Indonesia for instance is about 173 million tons in Kulon Progo, Jogyakarta. In addition, the new regulation of Energy and Mineral Resources Ministry required that iron sands must process before are being export. Therefore, the proper beneficiation methods are need to improve the iron content of iron sand. In this research Kulon Progo iron sand was used as a raw materials because not only the reserves very abundant but also the new iron making plant will build here soon. The combine of ore concentration methods such as tabling and magnetic separation used to improve the iron content. Then, the variable process were inclination of the table (2°,3° and 4°), fraction of feed size (-100 mesh, -150 mesh and -200 mesh) and the magnetic intensity (176, 830, 1500 Gauss). The highest recovery was about 96.75% and the concentrate which is contain 59.78 % Fe achieved by using -200 mesh particle size, 4° inclination of table and 1500 Gauss as a magnetic intensity. In conclusion, this concentrate fulfilled raw material requires of iron making (≥ 55%Fe).

  9. Method to enhance the performance of synthetic origin-destination (O-D) trip table estimation models.

    DOT National Transportation Integrated Search

    1998-01-01

    The conventional methods of determining origin-destination (O-D) trip tables involve elaborate surveys, e.g., home interviews, that require considerable time, staff, and funds. To overcome this drawback, a number of theoretical models that synthesize...

  10. Response of the microbial community to seasonal groundwater level fluctuations in petroleum hydrocarbon-contaminated groundwater.

    PubMed

    Zhou, Ai-xia; Zhang, Yu-ling; Dong, Tian-zi; Lin, Xue-yu; Su, Xiao-si

    2015-07-01

    The effects of seasonal groundwater level fluctuations on the contamination characteristics of total petroleum hydrocarbons (TPH) in soils, groundwater, and the microbial community were investigated at a typical petrochemical site in northern China. The measurements of groundwater and soil at different depths showed that significant TPH residue was present in the soil in this study area, especially in the vicinity of the pollution source, where TPH concentrations were up to 2600 mg kg(-1). The TPH concentration in the groundwater fluctuated seasonally, and the maximum variation was 0.8 mg L(-1). The highest TPH concentrations were detected in the silty clay layer and lied in the groundwater level fluctuation zones. The groundwater could reach previously contaminated areas in the soil, leading to higher groundwater TPH concentrations as TPH leaches into the groundwater. The coincident variation of the electron acceptors and TPH concentration with groundwater-table fluctuations affected the microbial communities in groundwater. The microbial community structure was significantly different between the wet and dry seasons. The canonical correspondence analysis (CCA) results showed that in the wet season, TPH, NO3(-), Fe(2+), TMn, S(2-), and HCO3(-) were the major factors correlating the microbial community. A significant increase in abundance of operational taxonomic unit J1 (97% similar to Dechloromonas aromatica sp.) was also observed in wet season conditions, indicating an intense denitrifying activity in the wet season environment. In the dry season, due to weak groundwater level fluctuations and low temperature of groundwater, the microbial activity was weak. But iron and sulfate-reducing were also detected in dry season at this site. As a whole, groundwater-table fluctuations would affect the distribution, transport, and biodegradation of the contaminants. These results may be valuable for the control and remediation of soil and groundwater pollution at this site

  11. Detection limit for rate fluctuations in inhomogeneous Poisson processes

    NASA Astrophysics Data System (ADS)

    Shintani, Toshiaki; Shinomoto, Shigeru

    2012-04-01

    Estimations of an underlying rate from data points are inevitably disturbed by the irregular occurrence of events. Proper estimation methods are designed to avoid overfitting by discounting the irregular occurrence of data, and to determine a constant rate from irregular data derived from a constant probability distribution. However, it can occur that rapid or small fluctuations in the underlying density are undetectable when the data are sparse. For an estimation method, the maximum degree of undetectable rate fluctuations is uniquely determined as a phase transition, when considering an infinitely long series of events drawn from a fluctuating density. In this study, we analytically examine an optimized histogram and a Bayesian rate estimator with respect to their detectability of rate fluctuation, and determine whether their detectable-undetectable phase transition points are given by an identical formula defining a degree of fluctuation in an underlying rate. In addition, we numerically examine the variational Bayes hidden Markov model in its detectability of rate fluctuation, and determine whether the numerically obtained transition point is comparable to those of the other two methods. Such consistency among these three principled methods suggests the presence of a theoretical limit for detecting rate fluctuations.

  12. Detection limit for rate fluctuations in inhomogeneous Poisson processes.

    PubMed

    Shintani, Toshiaki; Shinomoto, Shigeru

    2012-04-01

    Estimations of an underlying rate from data points are inevitably disturbed by the irregular occurrence of events. Proper estimation methods are designed to avoid overfitting by discounting the irregular occurrence of data, and to determine a constant rate from irregular data derived from a constant probability distribution. However, it can occur that rapid or small fluctuations in the underlying density are undetectable when the data are sparse. For an estimation method, the maximum degree of undetectable rate fluctuations is uniquely determined as a phase transition, when considering an infinitely long series of events drawn from a fluctuating density. In this study, we analytically examine an optimized histogram and a Bayesian rate estimator with respect to their detectability of rate fluctuation, and determine whether their detectable-undetectable phase transition points are given by an identical formula defining a degree of fluctuation in an underlying rate. In addition, we numerically examine the variational Bayes hidden Markov model in its detectability of rate fluctuation, and determine whether the numerically obtained transition point is comparable to those of the other two methods. Such consistency among these three principled methods suggests the presence of a theoretical limit for detecting rate fluctuations.

  13. Groundwater table fluctuations recorded in zonation of microbial siderites from end-Triassic strata

    NASA Astrophysics Data System (ADS)

    Weibel, R.; Lindström, S.; Pedersen, G. K.; Johansson, L.; Dybkjær, K.; Whitehouse, M. J.; Boyce, A. J.; Leng, M. J.

    2016-08-01

    In a terrestrial Triassic-Jurassic boundary succession of southern Sweden, perfectly zoned sphaerosiderites are restricted to a specific sandy interval deposited during the end-Triassic event. Underlying and overlying this sand interval there are several other types of siderite micromorphologies, i.e. poorly zoned sphaerosiderite, spheroidal (ellipsoid) siderite, spherical siderite and rhombohedral siderite. Siderite overgrowths occur mainly as rhombohedral crystals on perfectly zoned sphaerosiderite and as radiating fibrous crystals on spheroidal siderite. Concretionary sparry, microspar and/or micritic siderite cement postdate all of these micromorphologies. The carbon isotope composition of the siderite measured by conventional mass spectrometry shows the characteristic broad span of data, probably as a result of multiple stages of microbial activity. SIMS (secondary ion mass spectrometry) revealed generally higher δ13C values for the concretionary cement than the perfectly zoned sphaerosiderite, spheroidal siderite and their overgrowths, which marks a change in the carbon source during burial. All the various siderite morphologies have almost identical oxygen isotope values reflecting the palaeo-groundwater composition. A pedogenic/freshwater origin is supported by the trace element compositions of varying Fe:Mn ratios and low Mg contents. Fluctuating groundwater is the most likely explanation for uniform repeated siderite zones of varying Fe:Mn ratios reflecting alternating physiochemical conditions and hostility to microbial life/activity. Bacterially mediated siderite precipitation likely incorporated Mn and other metal ions during conditions that are not favourable for the bacteria and continued with Fe-rich siderite precipitation as the physico-chemical conditions changed into optimal conditions again, reflecting the response to groundwater fluctuations.

  14. Evidence reasoning method for constructing conditional probability tables in a Bayesian network of multimorbidity.

    PubMed

    Du, Yuanwei; Guo, Yubin

    2015-01-01

    The intrinsic mechanism of multimorbidity is difficult to recognize and prediction and diagnosis are difficult to carry out accordingly. Bayesian networks can help to diagnose multimorbidity in health care, but it is difficult to obtain the conditional probability table (CPT) because of the lack of clinically statistical data. Today, expert knowledge and experience are increasingly used in training Bayesian networks in order to help predict or diagnose diseases, but the CPT in Bayesian networks is usually irrational or ineffective for ignoring realistic constraints especially in multimorbidity. In order to solve these problems, an evidence reasoning (ER) approach is employed to extract and fuse inference data from experts using a belief distribution and recursive ER algorithm, based on which evidence reasoning method for constructing conditional probability tables in Bayesian network of multimorbidity is presented step by step. A multimorbidity numerical example is used to demonstrate the method and prove its feasibility and application. Bayesian network can be determined as long as the inference assessment is inferred by each expert according to his/her knowledge or experience. Our method is more effective than existing methods for extracting expert inference data accurately and is fused effectively for constructing CPTs in a Bayesian network of multimorbidity.

  15. 40 CFR Table C-3 to Subpart C of... - Test Specifications for Pb in TSP and Pb in PM 10 Methods

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 6 2014-07-01 2014-07-01 false Test Specifications for Pb in TSP and Pb in PM 10 Methods C Table C-3 to Subpart C of Part 53 Protection of Environment ENVIRONMENTAL..., Subpt. C, Table C-3 Table C-3 to Subpart C of Part 53—Test Specifications for Pb in TSP and Pb in PM 10...

  16. 40 CFR Table C-3 to Subpart C of... - Test Specifications for Pb in TSP and Pb in PM 10 Methods

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 6 2013-07-01 2013-07-01 false Test Specifications for Pb in TSP and Pb in PM 10 Methods C Table C-3 to Subpart C of Part 53 Protection of Environment ENVIRONMENTAL..., Subpt. C, Table C-3 Table C-3 to Subpart C of Part 53—Test Specifications for Pb in TSP and Pb in PM 10...

  17. 40 CFR Table C-3 to Subpart C of... - Test Specifications for Pb in TSP and Pb in PM10 Methods

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 6 2012-07-01 2012-07-01 false Test Specifications for Pb in TSP and Pb in PM10 Methods C Table C-3 to Subpart C of Part 53 Protection of Environment ENVIRONMENTAL..., Subpt. C, Table C-3 Table C-3 to Subpart C of Part 53—Test Specifications for Pb in TSP and Pb in PM10...

  18. Response of Groundwater table to Eucalyptus Plantations in a Tropical Monsoon Climate, Lake Tana Basin, Ethiopia

    NASA Astrophysics Data System (ADS)

    Enku, Temesgen; Melesse, Assefa; Ayana, Essaya; Tilahun, Seifu; Abate, Mengiste; Steenhuis, Tammo

    2017-04-01

    Given the increasing demand for water resources and the need for better management of regional water resources, it is essential to quantify the groundwater use by phreatophytes in tropical monsoon climates. Phreatophytes, like eucalyptus plantations are reported to be a groundwater sink and it could significantly affect the regional groundwater resources. In our study, the consumptive groundwater use of a closed eucalyptus plantation was calculated based on the diurnal water table fluctuations observed in monitoring wells for two dry monsoon phases in the Fogera plain, northwest of Ethiopia. Automated recorders were installed to monitor the hourly groundwater table fluctuations. The groundwater table fluctuates from maximum at early in the morning to minimum in the evening daily and generally declined linearly during the dry phase averaging 3.1 cm/day during the two year period under the eucalyptus plantations. The hourly eucalypts transpiration rate over the daylight hours follows the daily solar irradiance curve for clear sky days. It is minimal during the night and reaches maximum of 1.65mm/hour at mid-day. The evapotranspiration from the groundwater by eucalyptus plantations during the dry phases was estimated at about 2300mm from October 1 to 31 May, in 2015 compared to about 900mm without eucalyptus trees. The average daily evapotranspiration was 9.6mm. This is almost twice of the reference evapotranspiration in the area and 2.5 times the actual rate under fallow agricultural fields. Thus, water resources planning and management in the region needs to consider the effect of eucalyptus plantations on the availability of groundwater resources in the highlands of Ethiopia. Key words: Eucalyptus, Evapotranspiration, Groundwater, Ethiopia, Lake Tana

  19. Verifying detailed fluctuation relations for discrete feedback-controlled quantum dynamics

    NASA Astrophysics Data System (ADS)

    Camati, Patrice A.; Serra, Roberto M.

    2018-04-01

    Discrete quantum feedback control consists of a managed dynamics according to the information acquired by a previous measurement. Energy fluctuations along such dynamics satisfy generalized fluctuation relations, which are useful tools to study the thermodynamics of systems far away from equilibrium. Due to the practical challenge to assess energy fluctuations in the quantum scenario, the experimental verification of detailed fluctuation relations in the presence of feedback control remains elusive. We present a feasible method to experimentally verify detailed fluctuation relations for discrete feedback control quantum dynamics. Two detailed fluctuation relations are developed and employed. The method is based on a quantum interferometric strategy that allows the verification of fluctuation relations in the presence of feedback control. An analytical example to illustrate the applicability of the method is discussed. The comprehensive technique introduced here can be experimentally implemented at a microscale with the current technology in a variety of experimental platforms.

  20. Constructing stage-structured matrix population models from life tables: comparison of methods

    PubMed Central

    Diaz-Lopez, Jasmin

    2017-01-01

    A matrix population model is a convenient tool for summarizing per capita survival and reproduction rates (collectively vital rates) of a population and can be used for calculating an asymptotic finite population growth rate (λ) and generation time. These two pieces of information can be used for determining the status of a threatened species. The use of stage-structured population models has increased in recent years, and the vital rates in such models are often estimated using a life table analysis. However, potential bias introduced when converting age-structured vital rates estimated from a life table into parameters for a stage-structured population model has not been assessed comprehensively. The objective of this study was to investigate the performance of methods for such conversions using simulated life histories of organisms. The underlying models incorporate various types of life history and true population growth rates of varying levels. The performance was measured by comparing differences in λ and the generation time calculated using the Euler-Lotka equation, age-structured population matrices, and several stage-structured population matrices that were obtained by applying different conversion methods. The results show that the discretization of age introduces only small bias in λ or generation time. Similarly, assuming a fixed age of maturation at the mean age of maturation does not introduce much bias. However, aggregating age-specific survival rates into a stage-specific survival rate and estimating a stage-transition rate can introduce substantial bias depending on the organism’s life history type and the true values of λ. In order to aggregate survival rates, the use of the weighted arithmetic mean was the most robust method for estimating λ. Here, the weights are given by survivorship curve after discounting with λ. To estimate a stage-transition rate, matching the proportion of individuals transitioning, with λ used for discounting the

  1. Constructing stage-structured matrix population models from life tables: comparison of methods.

    PubMed

    Fujiwara, Masami; Diaz-Lopez, Jasmin

    2017-01-01

    A matrix population model is a convenient tool for summarizing per capita survival and reproduction rates (collectively vital rates) of a population and can be used for calculating an asymptotic finite population growth rate ( λ ) and generation time. These two pieces of information can be used for determining the status of a threatened species. The use of stage-structured population models has increased in recent years, and the vital rates in such models are often estimated using a life table analysis. However, potential bias introduced when converting age-structured vital rates estimated from a life table into parameters for a stage-structured population model has not been assessed comprehensively. The objective of this study was to investigate the performance of methods for such conversions using simulated life histories of organisms. The underlying models incorporate various types of life history and true population growth rates of varying levels. The performance was measured by comparing differences in λ and the generation time calculated using the Euler-Lotka equation, age-structured population matrices, and several stage-structured population matrices that were obtained by applying different conversion methods. The results show that the discretization of age introduces only small bias in λ or generation time. Similarly, assuming a fixed age of maturation at the mean age of maturation does not introduce much bias. However, aggregating age-specific survival rates into a stage-specific survival rate and estimating a stage-transition rate can introduce substantial bias depending on the organism's life history type and the true values of λ . In order to aggregate survival rates, the use of the weighted arithmetic mean was the most robust method for estimating λ . Here, the weights are given by survivorship curve after discounting with λ . To estimate a stage-transition rate, matching the proportion of individuals transitioning, with λ used for discounting

  2. Method and apparatus for automatically generating airfoil performance tables

    NASA Technical Reports Server (NTRS)

    van Dam, Cornelis P. (Inventor); Mayda, Edward A. (Inventor); Strawn, Roger Clayton (Inventor)

    2006-01-01

    One embodiment of the present invention provides a system that facilitates automatically generating a performance table for an object, wherein the object is subject to fluid flow. The system operates by first receiving a description of the object and testing parameters for the object. The system executes a flow solver using the testing parameters and the description of the object to produce an output. Next, the system determines if the output of the flow solver indicates negative density or pressure. If not, the system analyzes the output to determine if the output is converging. If converging, the system writes the output to the performance table for the object.

  3. Optimization of gold ore Sumbawa separation using gravity method: Shaking table

    NASA Astrophysics Data System (ADS)

    Ferdana, Achmad Dhaefi; Petrus, Himawan Tri Bayu Murti; Bendiyasa, I. Made; Prijambada, Irfan Dwidya; Hamada, Fumio; Sachiko, Takahi

    2018-04-01

    Most of artisanal small gold mining in Indonesia has been using amalgamation method, which caused negative impact to the environment around ore processing area due to the usage of mercury. One of the more environmental-friendly method for gold processing is gravity method. Shaking table is one of separation equipment of gravity method used to increase concentrate based on difference of specific gravity. The optimum concentration result is influenced by several variables, such as rotational speed shaking, particle size and deck slope. In this research, the range of rotational speed shaking was between 100 rpm and 200 rpm, the particle size was between -100 + 200 mesh and -200 + 300 mesh and deck slope was between 3° and 7°. Gold concentration in concentrate was measured by EDX. The result shows that the optimum condition is obtained at a shaking speed of 200 rpm, with a slope of 7° and particle size of -100 + 200 mesh.

  4. An efficient and guaranteed stable numerical method for continuous modeling of infiltration and redistribution with a shallow dynamic water table

    NASA Astrophysics Data System (ADS)

    Lai, Wencong; Ogden, Fred L.; Steinke, Robert C.; Talbot, Cary A.

    2015-03-01

    We have developed a one-dimensional numerical method to simulate infiltration and redistribution in the presence of a shallow dynamic water table. This method builds upon the Green-Ampt infiltration with Redistribution (GAR) model and incorporates features from the Talbot-Ogden (T-O) infiltration and redistribution method in a discretized moisture content domain. The redistribution scheme is more physically meaningful than the capillary weighted redistribution scheme in the T-O method. Groundwater dynamics are considered in this new method instead of hydrostatic groundwater front. It is also computationally more efficient than the T-O method. Motion of water in the vadose zone due to infiltration, redistribution, and interactions with capillary groundwater are described by ordinary differential equations. Numerical solutions to these equations are computationally less expensive than solutions of the highly nonlinear Richards' (1931) partial differential equation. We present results from numerical tests on 11 soil types using multiple rain pulses with different boundary conditions, with and without a shallow water table and compare against the numerical solution of Richards' equation (RE). Results from the new method are in satisfactory agreement with RE solutions in term of ponding time, deponding time, infiltration rate, and cumulative infiltrated depth. The new method, which we call "GARTO" can be used as an alternative to the RE for 1-D coupled surface and groundwater models in general situations with homogeneous soils with dynamic water table. The GARTO method represents a significant advance in simulating groundwater surface water interactions because it very closely matches the RE solution while being computationally efficient, with guaranteed mass conservation, and no stability limitations that can affect RE solvers in the case of a near-surface water table.

  5. Influence of water table fluctuations on subsurface methane dynamics and surface fluxes in seasonally flooded subtropical pastures.

    NASA Astrophysics Data System (ADS)

    Chamberlain, S.; Gomez-Casanovas, N.; Boughton, E.; Keel, E.; Walter, M. T.; Groffman, P. M.; Sparks, J. P.

    2015-12-01

    Seasonally flooded subtropical pastures are major sources of methane (CH4), and periodic flooding drives complex emission dynamics from these ecosystems. Understanding the mechanisms of belowground CH4 dynamics driving soil surface fluxes is needed to better understand emissions from these systems and their response to environmental change. We investigated subsurface CH4 dynamics in relation to net surface fluxes using laboratory water table manipulations and compared these results to eddy covariance-measured fluxes to link within-soil CH4 dynamics to observed ecosystem fluxes. Pronounced hysteresis was observed in ecosystem CH4 fluxes during precipitation driven flooding events. This dynamic was replicated in mesocosm experiments, with maximum CH4 fluxes observed during periods of water table recession. Hysteresis dynamics were best explained by oxygen dynamics during precipitation recharge events and the oxidation of CH4 produced in organic soil horizons during water table recession. We observed distinct CH4 dynamics between surface organic and deeper mineral soil horizons. In surface organic soil horizons, high levels of CH4 production were temporally linked to observed surface emissions. In contrast, high concentrations of CH4 observed in deeper mineral soils did not contribute to surface fluxes. Methane production potentials in surface organic soils were orders of magnitude higher than in mineral soils, suggesting that over longer flooding regimes CH4 produced in mineral horizons is unlikely to be a significant component of net surface emissions. Our results demonstrate that distinct CH4 dynamics may be stratified by depth, and flooding of the near-surface organic soils drives the high magnitude CH4 fluxes observed from subtropical pastures. These results suggest that relatively small changes in pasture water table dynamics can drive large changes in net CH4 emissions if surface organic soils remain saturated over longer time scales.

  6. Method to calibrate phase fluctuation in polarization-sensitive swept-source optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Lu, Zenghai; Kasaragod, Deepa K.; Matcher, Stephen J.

    2011-07-01

    We present a phase fluctuation calibration method for polarization-sensitive swept-source optical coherence tomography (PS-SS-OCT) using continuous polarization modulation. The method uses a low-voltage broadband polarization modulator driven by a synchronized sinusoidal burst waveform rather than an asynchronous waveform, together with the removal of the global phases of the measured Jones matrices by the use of matrix normalization. This makes it possible to average the measured Jones matrices to remove the artifact due to the speckle noise of the signal in the sample without introducing auxiliary optical components into the sample arm. This method was validated on measurements of an equine tendon sample by the PS-SS-OCT system.

  7. Detection of small-amplitude periodic surface pressure fluctuation by pressure-sensitive paint measurements using frequency-domain methods

    NASA Astrophysics Data System (ADS)

    Noda, Takahiro; Nakakita, Kazuyki; Wakahara, Masaki; Kameda, Masaharu

    2018-06-01

    Image measurement using pressure-sensitive paint (PSP) is an effective tool for analyzing the unsteady pressure field on the surface of a body in a low-speed air flow, which is associated with wind noise. In this study, the surface pressure fluctuation due to the tonal trailing edge (TE) noise for a two-dimensional NACA 0012 airfoil was quantitatively detected using a porous anodized aluminum PSP (AA-PSP). The emission from the PSP upon illumination by a blue laser diode was captured using a 12-bit high-speed complementary metal-oxide-semiconductor (CMOS) camera. The intensities of the captured images were converted to pressures using a standard intensity-based method. Three image-processing methods based on the fast Fourier transform (FFT) were tested to determine their efficiency in improving the signal-to-noise ratio (SNR) of the unsteady PSP data. In addition to two fundamental FFT techniques (the full data and ensemble averaging FFTs), a technique using the coherent output power (COP), which involves the cross correlation between the PSP data and the signal measured using a pointwise sound-level meter, was tested. Preliminary tests indicated that random photon shot noise dominates the intensity fluctuations in the captured PSP emissions above 200 Hz. Pressure fluctuations associated with the TE noise, whose dominant frequency is approximately 940 Hz, were successfully measured by analyzing 40,960 sequential PSP images recorded at 10 kfps. Quantitative validation using the power spectrum indicates that the COP technique is the most effective method of identification of the pressure fluctuation directly related to TE noise. It is possible to distinguish power differences with a resolution of 10 Pa^2 (4 Pa in amplitude) when the COP was employed without use of another wind-off data. This resolution cannot be achieved by the ensemble averaging FFT because of an insufficient elimination of the background noise.

  8. 40 CFR Table C-4 to Subpart C of... - Test Specifications for PM 10, PM 2.5 and PM 10-2.5 Candidate Equivalent Methods

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 6 2014-07-01 2014-07-01 false Test Specifications for PM 10, PM 2.5 and PM 10-2.5 Candidate Equivalent Methods C Table C-4 to Subpart C of Part 53 Protection of... Reference Methods Pt. 53, Subpt. C, Table C-4 Table C-4 to Subpart C of Part 53—Test Specifications for PM...

  9. 40 CFR Table C-4 to Subpart C of... - Test Specifications for PM 10, PM 2.5 and PM 10-2.5 Candidate Equivalent Methods

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 6 2013-07-01 2013-07-01 false Test Specifications for PM 10, PM 2.5 and PM 10-2.5 Candidate Equivalent Methods C Table C-4 to Subpart C of Part 53 Protection of... Reference Methods Pt. 53, Subpt. C, Table C-4 Table C-4 to Subpart C of Part 53—Test Specifications for PM...

  10. Quantifying economic fluctuations by adapting methods of statistical physics

    NASA Astrophysics Data System (ADS)

    Plerou, Vasiliki

    2001-09-01

    The first focus of this thesis is the investigation of cross-correlations between the price fluctuations of different stocks using the conceptual framework of random matrix theory (RMT), developed in physics to describe the statistical properties of energy-level spectra of complex nuclei. RMT makes predictions for the statistical properties of matrices that are universal, i.e., do not depend on the interactions between the elements comprising the system. In physical systems, deviations from the predictions of RMT provide clues regarding the mechanisms controlling the dynamics of a given system so this framework is of potential value if applied to economic systems. This thesis compares the statistics of cross-correlation matrix C-whose elements Cij are the correlation coefficients of price fluctuations of stock i and j-against the ``null hypothesis'' of a random matrix having the same symmetry properties. It is shown that comparison of the eigenvalue statistics of C with RMT results can be used to distinguish random and non-random parts of C. The non-random part of C which deviates from RMT results, provides information regarding genuine cross-correlations between stocks. The interpretations and potential practical utility of these deviations are also investigated. The second focus is the characterization of the dynamics of stock price fluctuations. The statistical properties of the changes G Δt in price over a time interval Δ t are quantified and the statistical relation between G Δt and the trading activity-measured by the number of transactions NΔ t in the interval Δt is investigated. The statistical properties of the volatility, i.e., the time dependent standard deviation of price fluctuations, is related to two microscopic quantities: NΔt and the variance W2Dt of the price changes for all transactions in the interval Δ t. In addition, the statistical relationship between G Δt and the number of

  11. A method to enhance the performance of synthetic origin-destination (O-D) trip table estimation models.

    DOT National Transportation Integrated Search

    1998-01-01

    The conventional methods of determining origin-destination (O-D) trip tables involve elaborate surveys, e.g., home interviews, that require considerable time, staff, and funds. To overcome this drawback, a number of theoretical models that synthesize...

  12. Standardized Pearson type 3 density function area tables

    NASA Technical Reports Server (NTRS)

    Cohen, A. C.; Helm, F. R.; Sugg, M.

    1971-01-01

    Tables constituting extension of similar tables published in 1936 are presented in report form. Single and triple parameter gamma functions are discussed. Report tables should interest persons concerned with development and use of numerical analysis and evaluation methods.

  13. Regulation of Methane Oxidation in a Freshwater Wetland by Water Table Changes and Anoxia

    NASA Technical Reports Server (NTRS)

    Roslev, Peter; King, Gary M.

    1996-01-01

    The effects of water table fluctuations and anoxia on methane emission and methane oxidation were studied in a freshwater marsh. Seasonal aerobic methane oxidation rates varied between 15% and 76% of the potential diffusive methane flux (diffusive flux in the absence of aerobic oxidation). On an annual basis, approximately 43% of the methane diffusing into the oxic zone was oxidized before reaching the atmosphere. The highest methane oxidation was observed when the water table was below the peat surface. This was confirmed in laboratory experiments where short-term decreases in water table levels increased methane oxidation but also net methane emission. Although methane emission was generally not observed during the winter, stems of soft rush (Juncus effusus) emitted methane when the marsh was ice covered. Indigenous methanotrophic bacteria from the wetiand studied were relatively anoxia tolerant. Surface peat incubated under anoxic conditions maintained 30% of the initial methane oxidation capacity after 32 days of anoxia. Methanotrophs from anoxic peat initiated aerobic methane oxidation relatively quickly after oxygen addition (1-7 hours). These results were supported by culture experiments with the methanotroph Methylosinus trichosporium OB3b. This organism maintained a greater capacity for aerobic methane oxidation when starved under anoxic compared to oxic conditions. Anoxic incubation of M. trichosporium OB3b in the presence of sulfide (2 mM) and a low redox potential (-110 mV) did not decrease the capacity for methane oxidation relative to anoxic cultures incubated without sulfide. The results suggest that aerobic methane oxidation was a major regulator of seasonal methane emission front the investigated wetland. The observed water table fluctuations affected net methane oxidation presumably due to associated changes in oxygen gradients. However, changes from oxic to anoxic conditions in situ had relatively little effect on survival of the methanotrophic

  14. A New Control Method to Mitigate Power Fluctuations for Grid Integrated PV/Wind Hybrid Power System Using Ultracapacitors

    NASA Astrophysics Data System (ADS)

    Jayalakshmi, N. S.; Gaonkar, D. N.

    2016-08-01

    The output power obtained from solar-wind hybrid system fluctuates with changes in weather conditions. These power fluctuations cause adverse effects on the voltage, frequency and transient stability of the utility grid. In this paper, a control method is presented for power smoothing of grid integrated PV/wind hybrid system using ultracapacitors in a DC coupled structure. The power fluctuations of hybrid system are mitigated and smoothed power is supplied to the utility grid. In this work both photovoltaic (PV) panels and the wind generator are controlled to operate at their maximum power point. The grid side inverter control strategy presented in this paper maintains DC link voltage constant while injecting power to the grid at unity power factor considering different operating conditions. Actual solar irradiation and wind speed data are used in this study to evaluate the performance of the developed system using MATLAB/Simulink software. The simulation results show that output power fluctuations of solar-wind hybrid system can be significantly mitigated using the ultracapacitor based storage system.

  15. Entropy in bimolecular simulations: A comprehensive review of atomic fluctuations-based methods.

    PubMed

    Kassem, Summer; Ahmed, Marawan; El-Sheikh, Salah; Barakat, Khaled H

    2015-11-01

    Entropy of binding constitutes a major, and in many cases a detrimental, component of the binding affinity in biomolecular interactions. While the enthalpic part of the binding free energy is easier to calculate, estimating the entropy of binding is further more complicated. A precise evaluation of entropy requires a comprehensive exploration of the complete phase space of the interacting entities. As this task is extremely hard to accomplish in the context of conventional molecular simulations, calculating entropy has involved many approximations. Most of these golden standard methods focused on developing a reliable estimation of the conformational part of the entropy. Here, we review these methods with a particular emphasis on the different techniques that extract entropy from atomic fluctuations. The theoretical formalisms behind each method is explained highlighting its strengths as well as its limitations, followed by a description of a number of case studies for each method. We hope that this brief, yet comprehensive, review provides a useful tool to understand these methods and realize the practical issues that may arise in such calculations. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Effect of water-table fluctuations on the degradation of Sphagnum phenols in surficial peats

    NASA Astrophysics Data System (ADS)

    Abbott, Geoffrey D.; Swain, Eleanor Y.; Muhammad, Aminu B.; Allton, Kathryn; Belyea, Lisa R.; Laing, Christopher G.; Cowie, Greg L.

    2013-04-01

    A much improved understanding of how water-table fluctuations near the surface affect decomposition and preservation of peat-forming plant litter and surficial peats is needed in order to predict possible feedbacks between the peatland carbon cycle and the global climate system. In this study peatland plants (bryophytes and vascular plants), their litter and peat cores were collected from the Ryggmossen peatland in the boreonemoral zone of central Sweden. The extracted insoluble residues from whole plant tissues were depolymerized using thermally assisted hydrolysis and methylation (THM) in the presence of both unlabelled and 13C-labelled tetramethylammonium hydroxide (TMAH) which yielded both vascular plant- and Sphagnum-derived phenols. Methylated 4-isopropenylphenol (IUPAC: 1-methoxy-4-(prop-1-en-2-yl)benzene), methylated cis- and trans-3-(4'-hydroxyphen-1-yl)but-2-enoic acid (IUPAC: (E/Z)-methyl 3-(4-methoxyphenyl)but-2-enoate), and methylated 3-(4'-hydroxyphen-1-yl)but-3-enoic acid (IUPAC: methyl 3-(4-methoxyphenyl)but-3-enoate) (van der Heijden et al., 1997) are confirmed as TMAH thermochemolysis products of "bound" sphagnum acid and also as being specific to Sphagnum mosses. These putative biomarkers were also significant components in the unlabelled TMAH thermochemolysis products from the depolymerization of ultrasonically extracted samples from eight peat cores, one from a hummock and one from a hollow at each of the four stages along the bog plateau-to-swamp forest gradient. We have proposed and measured two parameters namely (i) σ which is defined as the total amount of these four molecules normalised to 100 mg of OC; and (ii) an index (SR%) which is the ratio of σ to the Λ parameter giving a measure of the relative amounts of "bound" sphagnum acid to the "bound" vascular plant phenols in peat moss and the surficial peat layers. Changes in σ and SR% down the bog plateau (BP), bog margin (BM) and fen lagg (FL) cores in the Ryggmossen mire indicates

  17. Random River Fluctuations Shape the Root Profile of Riparian Plants

    NASA Astrophysics Data System (ADS)

    Perona, P.; Tron, S.; Gorla, L.; Schwarz, M.; Laio, F.; Ridolfi, L.

    2015-12-01

    Plant roots are recognized to play a key role in the riparian ecosystems: they contribute to the plant as well as to the streambank and bedforms stability, help to enhance the water quality of the river, and sustain the belowground biodiversity. The complexity of the root-system architecture recalls their remarkable ability to respond to environmental conditions, notably including soil heterogeneity, resource availability, and climate. In fluvial environments where nutrient availability is not a limiting factor for plant to grow, the root growth of phreatophytic plants is strongly influenced by water and oxygen availability in the soil. In this work, we demonstrate that the randomness of water table fluctuations, determined by streamflow stochastic variability, is likely to be the main driver for the root development strategy of riparian plants. A collection of root measurements from field and outdoor controlled experiments is used to demonstrate that the vertical root density distribution can be described by a simple analytical expression, whose parameters are linked to properties of soil, plant and water table fluctuations. This physically-based expression is able to predict riparian plant roots adaptability to different hydrological and pedologic scenarios in riverine environments. Hence, this model has great potential towards the comprehension of the effects of future climate and environmental changing conditions on plant adaptation and river ecomorphodynamic processes. Finally, we present an open access graphical user interface that we developed in order to estimate the vertical root distribution in fluvial environments and to make the model easily available to a wider scientific and professional audience.

  18. Evaluation of short-term tracer fluctuations in groundwater and soil air in a two year study

    NASA Astrophysics Data System (ADS)

    Jenner, Florian; Mayer, Simon; Aeschbach, Werner; Weissbach, Therese

    2016-04-01

    The application of gas tracers like noble gases (NGs), SF6 or CFCs in groundwater studies such as paleo temperature determination requires a detailed understanding of the dynamics of reactive and inert gases in the soil air with which the infiltrating water equilibrates. Due to microbial gas consumption and production, NG partial pressures in soil air can deviate from atmospheric air, an effect that could bias noble gas temperatures estimates if not taken into account. So far, such an impact on NG contents in groundwater has not been directly demonstrated. We provide the first long-term study of the above mentioned gas tracers and physical parameters in both the saturated and unsaturated soil zone, sampled continuously for more than two years near Mannheim (Germany). NG partial pressures in soil air correlate with soil moisture and the sum value of O2+CO2, with a maximal significant enhancement of 3-6% with respect to atmospheric air during summer time. Observed seasonal fluctuations result in a mass dependent fractionation of NGs in soil air. Concentrations of SF6 and CFCs in soil air are determined by corresponding fluctuations in local atmospheric air, caused by industrial emissions. Arising concentration peaks are damped with increasing soil depth. Shallow groundwater shows short-term NG fluctuations which are smoothed within a few meters below the water table. A correlation between NG contents of soil air and of groundwater is observable during strong recharge events. However, there is no evidence for a permanent influence of seasonal variations of soil air composition on shallow groundwater. Fluctuating NG contents in shallow groundwater are rather determined by variations of soil temperature and water table level. Our data gives evidence for a further temperature driven equilibration of groundwater with entrapped air bubbles within the topmost saturated zone, which permanently occurs even some years after recharge. Local subsurface temperature fluctuations

  19. Fluctuations of thermodynamic quantities calculated from the fundamental equation of thermodynamics

    NASA Astrophysics Data System (ADS)

    Yan, Zijun; Chen, Jincan

    1992-02-01

    On the basis of the probability distribution of the various values of the fluctuation and the fundamental equation of thermodynamics of any given system, a simple and useful method of calculating the fluctuations is presented. By using the method, the fluctuations of thermodynamic quantities can be directly determined from the fundamental equation of thermodynamics. Finally, some examples are given to illustrate the use of the method.

  20. Predicting Fluctuations in Cryptocurrency Transactions Based on User Comments and Replies.

    PubMed

    Kim, Young Bin; Kim, Jun Gi; Kim, Wook; Im, Jae Ho; Kim, Tae Hyeong; Kang, Shin Jin; Kim, Chang Hun

    2016-01-01

    This paper proposes a method to predict fluctuations in the prices of cryptocurrencies, which are increasingly used for online transactions worldwide. Little research has been conducted on predicting fluctuations in the price and number of transactions of a variety of cryptocurrencies. Moreover, the few methods proposed to predict fluctuation in currency prices are inefficient because they fail to take into account the differences in attributes between real currencies and cryptocurrencies. This paper analyzes user comments in online cryptocurrency communities to predict fluctuations in the prices of cryptocurrencies and the number of transactions. By focusing on three cryptocurrencies, each with a large market size and user base, this paper attempts to predict such fluctuations by using a simple and efficient method.

  1. Predicting Fluctuations in Cryptocurrency Transactions Based on User Comments and Replies

    PubMed Central

    Kim, Young Bin; Kim, Jun Gi; Kim, Wook; Im, Jae Ho; Kim, Tae Hyeong; Kang, Shin Jin; Kim, Chang Hun

    2016-01-01

    This paper proposes a method to predict fluctuations in the prices of cryptocurrencies, which are increasingly used for online transactions worldwide. Little research has been conducted on predicting fluctuations in the price and number of transactions of a variety of cryptocurrencies. Moreover, the few methods proposed to predict fluctuation in currency prices are inefficient because they fail to take into account the differences in attributes between real currencies and cryptocurrencies. This paper analyzes user comments in online cryptocurrency communities to predict fluctuations in the prices of cryptocurrencies and the number of transactions. By focusing on three cryptocurrencies, each with a large market size and user base, this paper attempts to predict such fluctuations by using a simple and efficient method. PMID:27533113

  2. Estimated Depth to Ground Water and Configuration of the Water Table in the Portland, Oregon Area

    USGS Publications Warehouse

    Snyder, Daniel T.

    2008-01-01

    Reliable information on the configuration of the water table in the Portland metropolitan area is needed to address concerns about various water-resource issues, especially with regard to potential effects from stormwater injection systems such as UIC (underground injection control) systems that are either existing or planned. To help address these concerns, this report presents the estimated depth-to-water and water-table elevation maps for the Portland area, along with estimates of the relative uncertainty of the maps and seasonal water-table fluctuations. The method of analysis used to determine the water-table configuration in the Portland area relied on water-level data from shallow wells and surface-water features that are representative of the water table. However, the largest source of available well data is water-level measurements in reports filed by well constructors at the time of new well installation, but these data frequently were not representative of static water-level conditions. Depth-to-water measurements reported in well-construction records generally were shallower than measurements by the U.S. Geological Survey (USGS) in the same or nearby wells, although many depth-to-water measurements were substantially deeper than USGS measurements. Magnitudes of differences in depth-to-water measurements reported in well records and those measured by the USGS in the same or nearby wells ranged from -119 to 156 feet with a mean of the absolute value of the differences of 36 feet. One possible cause for the differences is that water levels in many wells reported in well records were not at equilibrium at the time of measurement. As a result, the analysis of the water-table configuration relied on water levels measured during the current study or used in previous USGS investigations in the Portland area. Because of the scarcity of well data in some areas, the locations of select surface-water features including major rivers, streams, lakes, wetlands, and

  3. [Full Sibling Identification by IBS Scoring Method and Establishment of the Query Table of Its Critical Value].

    PubMed

    Li, R; Li, C T; Zhao, S M; Li, H X; Li, L; Wu, R G; Zhang, C C; Sun, H Y

    2017-04-01

    To establish a query table of IBS critical value and identification power for the detection systems with different numbers of STR loci under different false judgment standards. Samples of 267 pairs of full siblings and 360 pairs of unrelated individuals were collected and 19 autosomal STR loci were genotyped by Golden e ye™ 20A system. The full siblings were determined using IBS scoring method according to the 'Regulation for biological full sibling testing'. The critical values and identification power for the detection systems with different numbers of STR loci under different false judgment standards were calculated by theoretical methods. According to the formal IBS scoring criteria, the identification power of full siblings and unrelated individuals was 0.764 0 and the rate of false judgment was 0. The results of theoretical calculation were consistent with that of sample observation. The query table of IBS critical value for identification of full sibling detection systems with different numbers of STR loci was successfully established. The IBS scoring method defined by the regulation has high detection efficiency and low false judgment rate, which provides a relatively conservative result. The query table of IBS critical value for identification of full sibling detection systems with different numbers of STR loci provides an important reference data for the result judgment of full sibling testing and owns a considerable practical value. Copyright© by the Editorial Department of Journal of Forensic Medicine

  4. Event-by-event elliptic flow fluctuations from PHOBOS

    DOE PAGES

    Wosiek, Barbara; Alver, B.; Back, B. B.; ...

    2009-04-01

    Recently PHOBOS has focused on the study of fluctuations and correlations in particle production in heavy-ion collisions at the highest energies delivered by the Relativistic Heavy Ion Collider (RHIC). In this report, we present results on event-by-event elliptic flow fluctuations in Au + Au collisions at √s NN =200 GeV. A data-driven method was used to estimate the dominant contribution from non-flow correlations. Over the broad range of collision centralities, the observed large elliptic flow fluctuations are in agreement with the fluctuations in the initial source eccentricity.

  5. Event-by-Event Elliptic Flow Fluctuations from PHOBOS

    NASA Astrophysics Data System (ADS)

    Wosiek, B.; Alver, B.; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Busza, W.; Carroll, A.; Chai, Z.; Chetluru, V.; Decowski, M. P.; García, E.; Gburek, T.; George, N.; Gulbrandsen, K.; Halliwell, C.; Hamblen, J.; Harnarine, I.; Hauer, M.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Khan, N.; Kulinich, P.; Kuo, C. M.; Li, W.; Lin, W. T.; Loizides, C.; Manly, S.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Reed, C.; Richardson, E.; Roland, C.; Roland, G.; Sagerer, J.; Seals, H.; Sedykh, I.; Smith, C. E.; Stankiewicz, M. A.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Szostak, A.; Tonjes, M. B.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Vaurynovich, S. S.; Verdier, R.; Veres, G. I.; Walters, P.; Wenger, E.; Willhelm, D.; Wolfs, F. L. H.; Woźniak, K.; Wyngaardt, S.; Wysłouch, B.

    2009-04-01

    Recently PHOBOS has focused on the study of fluctuations and correlations in particle production in heavy-ion collisions at the highest energies delivered by the Relativistic Heavy Ion Collider (RHIC). In this report, we present results on event-by-event elliptic flow fluctuations in (Au+Au) collisions at sqrt {sNN}=200 GeV. A data-driven method was used to estimate the dominant contribution from non-flow correlations. Over the broad range of collision centralities, the observed large elliptic flow fluctuations are in agreement with the fluctuations in the initial source eccentricity.

  6. Comparing Performances of Multiple Comparison Methods in Commonly Used 2 × C Contingency Tables.

    PubMed

    Cangur, Sengul; Ankarali, Handan; Pasin, Ozge

    2016-12-01

    This study aims at mentioning briefly multiple comparison methods such as Bonferroni, Holm-Bonferroni, Hochberg, Hommel, Marascuilo, Tukey, Benjamini-Hochberg and Gavrilov-Benjamini-Sarkar for contingency tables, through the data obtained from a medical research and examining their performances by simulation study which was constructed as the total 36 scenarios to 2 × 4 contingency table. As results of simulation, it was observed that when the sample size is more than 100, the methods which can preserve the nominal alpha level are Gavrilov-Benjamini-Sarkar, Holm-Bonferroni and Bonferroni. Marascuilo method was found to be a more conservative than Bonferroni. It was found that Type I error rate for Hommel method is around 2 % in all scenarios. Moreover, when the proportions of the three populations are equal and the proportion value of the fourth population is far at a level of ±3 standard deviation from the other populations, the power value for Unadjusted All-Pairwise Comparison approach is at least a bit higher than the ones obtained by Gavrilov-Benjamini-Sarkar, Holm-Bonferroni and Bonferroni. Consequently, Gavrilov-Benjamini-Sarkar and Holm-Bonferroni methods have the best performance according to simulation. Hommel and Marascuilo methods are not recommended to be used because they have medium or lower performance. In addition, we have written a Minitab macro about multiple comparisons for use in scientific research.

  7. Stochastic simulation of reaction-diffusion systems: A fluctuating-hydrodynamics approach

    NASA Astrophysics Data System (ADS)

    Kim, Changho; Nonaka, Andy; Bell, John B.; Garcia, Alejandro L.; Donev, Aleksandar

    2017-03-01

    We develop numerical methods for stochastic reaction-diffusion systems based on approaches used for fluctuating hydrodynamics (FHD). For hydrodynamic systems, the FHD formulation is formally described by stochastic partial differential equations (SPDEs). In the reaction-diffusion systems we consider, our model becomes similar to the reaction-diffusion master equation (RDME) description when our SPDEs are spatially discretized and reactions are modeled as a source term having Poisson fluctuations. However, unlike the RDME, which becomes prohibitively expensive for an increasing number of molecules, our FHD-based description naturally extends from the regime where fluctuations are strong, i.e., each mesoscopic cell has few (reactive) molecules, to regimes with moderate or weak fluctuations, and ultimately to the deterministic limit. By treating diffusion implicitly, we avoid the severe restriction on time step size that limits all methods based on explicit treatments of diffusion and construct numerical methods that are more efficient than RDME methods, without compromising accuracy. Guided by an analysis of the accuracy of the distribution of steady-state fluctuations for the linearized reaction-diffusion model, we construct several two-stage (predictor-corrector) schemes, where diffusion is treated using a stochastic Crank-Nicolson method, and reactions are handled by the stochastic simulation algorithm of Gillespie or a weakly second-order tau leaping method. We find that an implicit midpoint tau leaping scheme attains second-order weak accuracy in the linearized setting and gives an accurate and stable structure factor for a time step size of an order of magnitude larger than the hopping time scale of diffusing molecules. We study the numerical accuracy of our methods for the Schlögl reaction-diffusion model both in and out of thermodynamic equilibrium. We demonstrate and quantify the importance of thermodynamic fluctuations to the formation of a two

  8. TOPMODEL simulations of streamflow and depth to water table in Fishing Brook Watershed, New York, 2007-09

    USGS Publications Warehouse

    Nystrom, Elizabeth A.; Burns, Douglas A.

    2011-01-01

    TOPMODEL uses a topographic wetness index computed from surface-elevation data to simulate streamflow and subsurface-saturation state, represented by the saturation deficit. Depth to water table was computed from simulated saturation-deficit values using computed soil properties. In the Fishing Brook Watershed, TOPMODEL was calibrated to the natural logarithm of streamflow at the study area outlet and depth to water table at Sixmile Wetland using a combined multiple-objective function. Runoff and depth to water table responded differently to some of the model parameters, and the combined multiple-objective function balanced the goodness-of-fit of the model realizations with respect to these parameters. Results show that TOPMODEL reasonably simulated runoff and depth to water table during the study period. The simulated runoff had a Nash-Sutcliffe efficiency of 0.738, but the model underpredicted total runoff by 14 percent. Depth to water table computed from simulated saturation-deficit values matched observed water-table depth moderately well; the root mean squared error of absolute depth to water table was 91 millimeters (mm), compared to the mean observed depth to water table of 205 mm. The correlation coefficient for temporal depth-to-water-table fluctuations was 0.624. The variability of the TOPMODEL simulations was assessed using prediction intervals grouped using the combined multiple-objective function. The calibrated TOPMODEL results for the entire study area were applied to several subwatersheds within the study area using computed hydrogeomorphic properties of the subwatersheds.

  9. A Table! (At the Table).

    ERIC Educational Resources Information Center

    Terry, Robert M.

    A review of French dining habits and table manners outlines: elements of the place setting, courtesies used at the table, serving conventions, restaurant tipping, the size and content of the different meals of the day, subtle differences in common foods, restaurant types, menu types, general wine and cheese choices, waiter-client communication,…

  10. Query-Adaptive Reciprocal Hash Tables for Nearest Neighbor Search.

    PubMed

    Liu, Xianglong; Deng, Cheng; Lang, Bo; Tao, Dacheng; Li, Xuelong

    2016-02-01

    Recent years have witnessed the success of binary hashing techniques in approximate nearest neighbor search. In practice, multiple hash tables are usually built using hashing to cover more desired results in the hit buckets of each table. However, rare work studies the unified approach to constructing multiple informative hash tables using any type of hashing algorithms. Meanwhile, for multiple table search, it also lacks of a generic query-adaptive and fine-grained ranking scheme that can alleviate the binary quantization loss suffered in the standard hashing techniques. To solve the above problems, in this paper, we first regard the table construction as a selection problem over a set of candidate hash functions. With the graph representation of the function set, we propose an efficient solution that sequentially applies normalized dominant set to finding the most informative and independent hash functions for each table. To further reduce the redundancy between tables, we explore the reciprocal hash tables in a boosting manner, where the hash function graph is updated with high weights emphasized on the misclassified neighbor pairs of previous hash tables. To refine the ranking of the retrieved buckets within a certain Hamming radius from the query, we propose a query-adaptive bitwise weighting scheme to enable fine-grained bucket ranking in each hash table, exploiting the discriminative power of its hash functions and their complement for nearest neighbor search. Moreover, we integrate such scheme into the multiple table search using a fast, yet reciprocal table lookup algorithm within the adaptive weighted Hamming radius. In this paper, both the construction method and the query-adaptive search method are general and compatible with different types of hashing algorithms using different feature spaces and/or parameter settings. Our extensive experiments on several large-scale benchmarks demonstrate that the proposed techniques can significantly outperform both

  11. A new algorithm for stand table projection models.

    Treesearch

    Quang V. Cao; V. Clark Baldwin

    1999-01-01

    The constrained least squares method is proposed as an algorithm for projecting stand tables through time. This method consists of three steps: (1) predict survival in each diameter class, (2) predict diameter growth, and (3) use the least squares approach to adjust the stand table to satisfy the constraints of future survival, average diameter, and stand basal area....

  12. Fluctuating hydrodynamics, current fluctuations, and hyperuniformity in boundary-driven open quantum chains

    NASA Astrophysics Data System (ADS)

    Carollo, Federico; Garrahan, Juan P.; Lesanovsky, Igor; Pérez-Espigares, Carlos

    2017-11-01

    We consider a class of either fermionic or bosonic noninteracting open quantum chains driven by dissipative interactions at the boundaries and study the interplay of coherent transport and dissipative processes, such as bulk dephasing and diffusion. Starting from the microscopic formulation, we show that the dynamics on large scales can be described in terms of fluctuating hydrodynamics. This is an important simplification as it allows us to apply the methods of macroscopic fluctuation theory to compute the large deviation (LD) statistics of time-integrated currents. In particular, this permits us to show that fermionic open chains display a third-order dynamical phase transition in LD functions. We show that this transition is manifested in a singular change in the structure of trajectories: while typical trajectories are diffusive, rare trajectories associated with atypical currents are ballistic and hyperuniform in their spatial structure. We confirm these results by numerically simulating ensembles of rare trajectories via the cloning method, and by exact numerical diagonalization of the microscopic quantum generator.

  13. Fluctuating hydrodynamics, current fluctuations, and hyperuniformity in boundary-driven open quantum chains.

    PubMed

    Carollo, Federico; Garrahan, Juan P; Lesanovsky, Igor; Pérez-Espigares, Carlos

    2017-11-01

    We consider a class of either fermionic or bosonic noninteracting open quantum chains driven by dissipative interactions at the boundaries and study the interplay of coherent transport and dissipative processes, such as bulk dephasing and diffusion. Starting from the microscopic formulation, we show that the dynamics on large scales can be described in terms of fluctuating hydrodynamics. This is an important simplification as it allows us to apply the methods of macroscopic fluctuation theory to compute the large deviation (LD) statistics of time-integrated currents. In particular, this permits us to show that fermionic open chains display a third-order dynamical phase transition in LD functions. We show that this transition is manifested in a singular change in the structure of trajectories: while typical trajectories are diffusive, rare trajectories associated with atypical currents are ballistic and hyperuniform in their spatial structure. We confirm these results by numerically simulating ensembles of rare trajectories via the cloning method, and by exact numerical diagonalization of the microscopic quantum generator.

  14. Verification of aerial photo stand volume tables for southeast Alaska.

    Treesearch

    Theodore S. Setzer; Bert R. Mead

    1988-01-01

    Aerial photo volume tables are used in the multilevel sampling system of Alaska Forest Inventory and Analysis. These volume tables are presented with a description of the data base and methods used to construct the tables. Volume estimates compiled from the aerial photo stand volume tables and associated ground-measured values are compared and evaluated.

  15. Maximum entropy, fluctuations and priors

    NASA Astrophysics Data System (ADS)

    Caticha, A.

    2001-05-01

    The method of maximum entropy (ME) is extended to address the following problem: Once one accepts that the ME distribution is to be preferred over all others, the question is to what extent are distributions with lower entropy supposed to be ruled out. Two applications are given. The first is to the theory of thermodynamic fluctuations. The formulation is exact, covariant under changes of coordinates, and allows fluctuations of both the extensive and the conjugate intensive variables. The second application is to the construction of an objective prior for Bayesian inference. The prior obtained by following the ME method to its inevitable conclusion turns out to be a special case (α=1) of what are currently known under the name of entropic priors. .

  16. Evaluation and analysis of current compaction methods for FDOT pipe trench backfills in areas of high water tables

    DOT National Transportation Integrated Search

    1999-01-01

    This research project was undertaken to examine the practicality and adequacy of the FDOT specifications regarding compaction methods for pipe trench backfills under high water table. Given the difficulty to determine density and to attain desired de...

  17. Stochastic simulation of reaction-diffusion systems: A fluctuating-hydrodynamics approach

    DOE PAGES

    Kim, Changho; Nonaka, Andy; Bell, John B.; ...

    2017-03-24

    Here, we develop numerical methods for stochastic reaction-diffusion systems based on approaches used for fluctuating hydrodynamics (FHD). For hydrodynamic systems, the FHD formulation is formally described by stochastic partial differential equations (SPDEs). In the reaction-diffusion systems we consider, our model becomes similar to the reaction-diffusion master equation (RDME) description when our SPDEs are spatially discretized and reactions are modeled as a source term having Poisson fluctuations. However, unlike the RDME, which becomes prohibitively expensive for an increasing number of molecules, our FHD-based description naturally extends from the regime where fluctuations are strong, i.e., each mesoscopic cell has few (reactive) molecules,more » to regimes with moderate or weak fluctuations, and ultimately to the deterministic limit. By treating diffusion implicitly, we avoid the severe restriction on time step size that limits all methods based on explicit treatments of diffusion and construct numerical methods that are more efficient than RDME methods, without compromising accuracy. Guided by an analysis of the accuracy of the distribution of steady-state fluctuations for the linearized reaction-diffusion model, we construct several two-stage (predictor-corrector) schemes, where diffusion is treated using a stochastic Crank-Nicolson method, and reactions are handled by the stochastic simulation algorithm of Gillespie or a weakly second-order tau leaping method. We find that an implicit midpoint tau leaping scheme attains second-order weak accuracy in the linearized setting and gives an accurate and stable structure factor for a time step size of an order of magnitude larger than the hopping time scale of diffusing molecules. We study the numerical accuracy of our methods for the Schlögl reaction-diffusion model both in and out of thermodynamic equilibrium. We demonstrate and quantify the importance of thermodynamic fluctuations to the formation of a

  18. Measuring multifractality of stock price fluctuation using multifractal detrended fluctuation analysis

    NASA Astrophysics Data System (ADS)

    Yuan, Ying; Zhuang, Xin-tian; Jin, Xiu

    2009-06-01

    Analyzing the Shanghai stock price index daily returns using MF-DFA method, it is found that there are two different types of sources for multifractality in time series, namely, fat-tailed probability distributions and non-linear temporal correlations. Based on that, a sliding window of 240 frequency data in 5 trading days was used to study stock price index fluctuation. It is found that when the stock price index fluctuates sharply, a strong variability is clearly characterized by the generalized Hurst exponents h(q). Therefore, two measures, Δh and σ, based on generalized Hurst exponents were proposed to compare financial risks before and after Price Limits and Reform of Non-tradable Shares. The empirical results verify the validity of the measures, and this has led to a better understanding of complex stock markets.

  19. Structural features that predict real-value fluctuations of globular proteins.

    PubMed

    Jamroz, Michal; Kolinski, Andrzej; Kihara, Daisuke

    2012-05-01

    It is crucial to consider dynamics for understanding the biological function of proteins. We used a large number of molecular dynamics (MD) trajectories of nonhomologous proteins as references and examined static structural features of proteins that are most relevant to fluctuations. We examined correlation of individual structural features with fluctuations and further investigated effective combinations of features for predicting the real value of residue fluctuations using the support vector regression (SVR). It was found that some structural features have higher correlation than crystallographic B-factors with fluctuations observed in MD trajectories. Moreover, SVR that uses combinations of static structural features showed accurate prediction of fluctuations with an average Pearson's correlation coefficient of 0.669 and a root mean square error of 1.04 Å. This correlation coefficient is higher than the one observed in predictions by the Gaussian network model (GNM). An advantage of the developed method over the GNMs is that the former predicts the real value of fluctuation. The results help improve our understanding of relationships between protein structure and fluctuation. Furthermore, the developed method provides a convienient practial way to predict fluctuations of proteins using easily computed static structural features of proteins. Copyright © 2012 Wiley Periodicals, Inc.

  20. Structural features that predict real-value fluctuations of globular proteins

    PubMed Central

    Jamroz, Michal; Kolinski, Andrzej; Kihara, Daisuke

    2012-01-01

    It is crucial to consider dynamics for understanding the biological function of proteins. We used a large number of molecular dynamics trajectories of non-homologous proteins as references and examined static structural features of proteins that are most relevant to fluctuations. We examined correlation of individual structural features with fluctuations and further investigated effective combinations of features for predicting the real-value of residue fluctuations using the support vector regression. It was found that some structural features have higher correlation than crystallographic B-factors with fluctuations observed in molecular dynamics trajectories. Moreover, support vector regression that uses combinations of static structural features showed accurate prediction of fluctuations with an average Pearson’s correlation coefficient of 0.669 and a root mean square error of 1.04 Å. This correlation coefficient is higher than the one observed for the prediction by the Gaussian network model. An advantage of the developed method over the Gaussian network models is that the former predicts the real-value of fluctuation. The results help improve our understanding of relationships between protein structure and fluctuation. Furthermore, the developed method provides a convienient practial way to predict fluctuations of proteins using easily computed static structural features of proteins. PMID:22328193

  1. a Mapping Method of Slam Based on Look up Table

    NASA Astrophysics Data System (ADS)

    Wang, Z.; Li, J.; Wang, A.; Wang, J.

    2017-09-01

    In the last years several V-SLAM(Visual Simultaneous Localization and Mapping) approaches have appeared showing impressive reconstructions of the world. However these maps are built with far more than the required information. This limitation comes from the whole process of each key-frame. In this paper we present for the first time a mapping method based on the LOOK UP TABLE(LUT) for visual SLAM that can improve the mapping effectively. As this method relies on extracting features in each cell divided from image, it can get the pose of camera that is more representative of the whole key-frame. The tracking direction of key-frames is obtained by counting the number of parallax directions of feature points. LUT stored all mapping needs the number of cell corresponding to the tracking direction which can reduce the redundant information in the key-frame, and is more efficient to mapping. The result shows that a better map with less noise is build using less than one-third of the time. We believe that the capacity of LUT efficiently building maps makes it a good choice for the community to investigate in the scene reconstruction problems.

  2. 40 CFR Table C-4 to Subpart C of... - Test Specifications for PM10, PM2.5 and PM10-2.5 Candidate Equivalent Methods

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 5 2011-07-01 2011-07-01 false Test Specifications for PM10, PM2.5 and PM10-2.5 Candidate Equivalent Methods C Table C-4 to Subpart C of Part 53 Protection of Environment... Pt. 53, Subpt. C, Table C-4 Table C-4 to Subpart C of Part 53—Test Specifications for PM10, PM2.5 and...

  3. 40 CFR Table C-4 to Subpart C of... - Test Specifications for PM10, PM2.5 and PM10-2.5 Candidate Equivalent Methods

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 6 2012-07-01 2012-07-01 false Test Specifications for PM10, PM2.5 and PM10-2.5 Candidate Equivalent Methods C Table C-4 to Subpart C of Part 53 Protection of Environment... Pt. 53, Subpt. C, Table C-4 Table C-4 to Subpart C of Part 53—Test Specifications for PM10, PM2.5 and...

  4. 40 CFR Table C-4 to Subpart C of... - Test Specifications for PM10, PM2.5 and PM10-2.5 Candidate Equivalent Methods

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Test Specifications for PM10, PM2.5 and PM10-2.5 Candidate Equivalent Methods C Table C-4 to Subpart C of Part 53 Protection of Environment... Pt. 53, Subpt. C, Table C-4 Table C-4 to Subpart C of Part 53—Test Specifications for PM10, PM2.5 and...

  5. Energetics of Table Tennis and Table Tennis-Specific Exercise Testing.

    PubMed

    Zagatto, Alessandro Moura; Leite, Jorge Vieira de Mello; Papoti, Marcelo; Beneke, Ralph

    2016-11-01

    To test the hypotheses that the metabolic profile of table tennis is dominantly aerobic, anaerobic energy is related to the accumulated duration and intensity of rallies, and activity and metabolic profile are interrelated with the individual fitness profile determined via table tennis-specific tests. Eleven male experienced table tennis players (22 ± 3 y, 77.6 ± 18.9 kg, 177.1 ± 8.1 cm) underwent 2 simulated table tennis matches to analyze aerobic (W OXID ) energy, anaerobic glycolytic (W BLC ) energy, and phosphocreatine breakdown (W PCr ); a table tennis-specific graded exercise test to measure ventilatory threshold and peak oxygen uptake; and an exhaustive supramaximal table tennis effort to determine maximal accumulated deficit of oxygen. W OXID , W BLC , and W PCr corresponded to 96.5% ± 1.7%, 1.0% ± 0.7%, and 2.5% ± 1.4%, respectively. W OXID was interrelated with rally duration (r = .81) and number of shots per rally (r = .77), whereas match intensity was correlated with WPCr (r = .62) and maximal accumulated oxygen deficit (r = .58). The metabolic profile of table tennis is predominantly aerobic and interrelated with the individual fitness profile determined via table tennis-specific tests. Table tennis-specific ventilatory threshold determines the average oxygen uptake and overall W OXID , whereas table tennis-specific maximal accumulated oxygen deficit indicates the ability to use and sustain slightly higher blood lactate concentration and W BLC during the match.

  6. Fluctuations, noise, and numerical methods in gyrokinetic particle-in-cell simulations

    NASA Astrophysics Data System (ADS)

    Jenkins, Thomas Grant

    In this thesis, the role of the "marker weight" (or "particle weight") used in gyrokinetic particle-in-cell (PIC) simulations is explored. Following a review of the foundations and major developments of gyrokinetic theory, key concepts of the Monte Carlo methods which form the basis for PIC simulations are set forth. Consistent with these methods, a Klimontovich representation for the set of simulation markers is developed in the extended phase space {R, v||, v ⊥, W, P} (with the additional coordinates representing weight fields); clear distinctions are consequently established between the marker distribution function and various physical distribution functions (arising from diverse moments of the marker distribution). Equations describing transport in the simulation are shown to be easily derivable using the formalism. The necessity of a two-weight model for nonequilibrium simulations is demonstrated, and a simple method for calculating the second (background-related) weight is presented. Procedures for arbitrary marker loading schemes in gyrokinetic PIC simulations are outlined; various initialization methods for simulations are compared. Possible effects of inadequate velocity-space resolution in gyrokinetic continuum simulations are explored. The "partial-f" simulation method is developed and its limitations indicated. A quasilinear treatment of electrostatic drift waves is shown to correctly predict nonlinear saturation amplitudes, and the relevance of the gyrokinetic fluctuation-dissipation theorem in assessing the effects of discrete-marker-induced statistical noise on the resulting marginally stable states is demonstrated.

  7. Linking Water Table Dynamics to Carbon Cycling in Artificial Soil Column Incubations

    NASA Astrophysics Data System (ADS)

    Geertje, Pronk; Adrian, Mellage; Tatjana, Milojevic; Fereidoun, Rezanezhad; Cappellen Philippe, Van

    2016-04-01

    The biogeochemistry of wetlands soils is closely tied to their hydrology. Water table fluctuations that cause flooding and drying of these systems may lead to enhanced degradation of organic matter and release of greenhouse gasses (e.g. CO2, CH4) to the atmosphere. However, predicting the influence of water table fluctuations on the biogeochemical functioning of soils requires an understanding of the interactions of soil hydrology with biogeochemical and microbial processes. To determine the effects of water table dynamics on carbon cycling, we are carrying out state-of-the-art automated soil column experiments with fully integrated monitoring of hydro-bio-geophysical process variables under both constant and oscillating water table conditions. An artificial, homogeneous mixture consisting of minerals and organic matter is used to provide a well-defined starting material. The artificial soils are composed of quartz sand, montmorillonite, goethite and humus from a forested riparian zone, from which we also extracted the microbial inoculum added to the soil mixture. The artificial soils are packed into 60 cm high, 7.5 cm wide columns. In the currently ongoing experiment, three replicate columns are incubated while keeping the water table constant water at mid-depth, while another three columns alternate between drained and saturated conditions. Micro-sensors installed at different depths below the soil surface record time-series redox potentials (Eh) varying between oxidizing (~+700 mV) and reducing (~-200 mV) conditions. Continuous O2 levels throughout the soil columns are monitored using high-resolution, luminescence-based, Multi Fiber Optode (MuFO) microsensors. Pore waters are collected periodically with MicroRhizon samplers from different depths, and analyzed for pH, EC, dissolved inorganic and organic carbon and ion/cation compositions. These measurements allow us to track the changes in pore water geochemistry and relate them to differences in carbon cycling

  8. [[Method of forming a multiple attrition life table and its application to the study of nuptiality among women in China

    PubMed

    Zeng, Y

    1987-01-01

    Trends in marital status among women in China for the period 1950-1970 and for 1981 are analyzed using the multiple decrement life table method. The results confirm those obtained with traditional methods of data analysis. It is found that over the past 30 years, Chinese women have experienced a high rate of marriage and a low divorce rate. The significant increase in age at marriage and the lowering of the death rate have affected marital status at all ages. The development of a marital status life table permits the author to estimate current numbers of women in the four marital statuses of unmarried, currently married, widowed, and divorced by age and their future likelihood of changing marital status.

  9. The European Southern Observatory-MIDAS table file system

    NASA Technical Reports Server (NTRS)

    Peron, M.; Grosbol, P.

    1992-01-01

    The new and substantially upgraded version of the Table File System in MIDAS is presented as a scientific database system. MIDAS applications for performing database operations on tables are discussed, for instance, the exchange of the data to and from the TFS, the selection of objects, the uncertainty joins across tables, and the graphical representation of data. This upgraded version of the TFS is a full implementation of the binary table extension of the FITS format; in addition, it also supports arrays of strings. Different storage strategies for optimal access of very large data sets are implemented and are addressed in detail. As a simple relational database, the TFS may be used for the management of personal data files. This opens the way to intelligent pipeline processing of large amounts of data. One of the key features of the Table File System is to provide also an extensive set of tools for the analysis of the final results of a reduction process. Column operations using standard and special mathematical functions as well as statistical distributions can be carried out; commands for linear regression and model fitting using nonlinear least square methods and user-defined functions are available. Finally, statistical tests of hypothesis and multivariate methods can also operate on tables.

  10. Plasma Diffusion in Self-Consistent Fluctuations

    NASA Technical Reports Server (NTRS)

    Smets, R.; Belmont, G.; Aunai, N.

    2012-01-01

    The problem of particle diffusion in position space, as a consequence ofeleclromagnetic fluctuations is addressed. Numerical results obtained with a self-consistent hybrid code are presented, and a method to calculate diffusion coefficient in the direction perpendicular to the mean magnetic field is proposed. The diffusion is estimated for two different types of fluctuations. The first type (resuiting from an agyrotropic in itiai setting)is stationary, wide band white noise, and associated to Gaussian probability distribution function for the magnetic fluctuations. The second type (result ing from a Kelvin-Helmholtz instability) is non-stationary, with a power-law spectrum, and a non-Gaussian probabi lity distribution function. The results of the study allow revisiting the question of loading particles of solar wind origin in the Earth magnetosphere.

  11. Hyper-Ramsey spectroscopy with probe-laser-intensity fluctuations

    NASA Astrophysics Data System (ADS)

    Beloy, K.

    2018-03-01

    We examine the influence of probe-laser-intensity fluctuations on hyper-Ramsey spectroscopy. We assume, as is appropriate for relevant cases of interest, that the probe-laser intensity I determines both the Rabi frequency (∝√{I } ) and the frequency shift to the atomic transition (∝I ) during probe-laser interactions with the atom. The spectroscopic signal depends on these two quantities that covary with fluctuations in the probe-laser intensity. Introducing a simple model for the fluctuations, we find that the signature robustness of the hyper-Ramsey method can be compromised. Taking the Yb+ electric octupole clock transition as an example, we quantify the clock error under different levels of probe-laser-intensity fluctuations.

  12. Higher-order correlations for fluctuations in the presence of fields.

    PubMed

    Boer, A; Dumitru, S

    2002-10-01

    The higher-order moments of the fluctuations for thermodynamic systems in the presence of fields are investigated in the framework of a theoretical method. The method uses a generalized statistical ensemble consistent with an adequate expression for the internal energy. The applications refer to the case of a system in a magnetoquasistatic field. In the case of linear magnetic media, one finds that, for the description of the magnetic induction fluctuations, the Gaussian approximation is satisfactory. For nonlinear media, the corresponding fluctuations are non-Gaussian, having a non-null asymmetry. Furthermore, the respective fluctuations have characteristics of leptokurtic, mesokurtic and platykurtic type, depending on the value of the magnetic field strength as compared with a scaling factor of the magnetization curve.

  13. Method to predict seasonal high ground water table (SHGWT) [summary].

    DOT National Transportation Integrated Search

    2017-04-01

    To help assure stability and long-term performance of pavement, a roadways base layer must : remain dry and be higher than the seasonal high groundwater table (SHGWT). Otherwise, the : roadways foundation can be weakened during certain times of...

  14. Method for evaluating compatibility of commercial electromagnetic (EM) microsensor tracking systems with surgical and imaging tables

    NASA Astrophysics Data System (ADS)

    Nafis, Christopher; Jensen, Vern; von Jako, Ron

    2008-03-01

    Electromagnetic (EM) tracking systems have been successfully used for Surgical Navigation in ENT, cranial, and spine applications for several years. Catheter sized micro EM sensors have also been used in tightly controlled cardiac mapping and pulmonary applications. EM systems have the benefit over optical navigation systems of not requiring a line-of-sight between devices. Ferrous metals or conductive materials that are transient within the EM working volume may impact tracking performance. Effective methods for detecting and reporting EM field distortions are generally well known. Distortion compensation can be achieved for objects that have a static spatial relationship to a tracking sensor. New commercially available micro EM tracking systems offer opportunities for expanded image-guided navigation procedures. It is important to know and understand how well these systems perform with different surgical tables and ancillary equipment. By their design and intended use, micro EM sensors will be located at the distal tip of tracked devices and therefore be in closer proximity to the tables. Our goal was to define a simple and portable process that could be used to estimate the EM tracker accuracy, and to vet a large number of popular general surgery and imaging tables that are used in the United States and abroad.

  15. Age correction in monitoring audiometry: method to update OSHA age-correction tables to include older workers

    PubMed Central

    Dobie, Robert A; Wojcik, Nancy C

    2015-01-01

    Objectives The US Occupational Safety and Health Administration (OSHA) Noise Standard provides the option for employers to apply age corrections to employee audiograms to consider the contribution of ageing when determining whether a standard threshold shift has occurred. Current OSHA age-correction tables are based on 40-year-old data, with small samples and an upper age limit of 60 years. By comparison, recent data (1999–2006) show that hearing thresholds in the US population have improved. Because hearing thresholds have improved, and because older people are increasingly represented in noisy occupations, the OSHA tables no longer represent the current US workforce. This paper presents 2 options for updating the age-correction tables and extending values to age 75 years using recent population-based hearing survey data from the US National Health and Nutrition Examination Survey (NHANES). Both options provide scientifically derived age-correction values that can be easily adopted by OSHA to expand their regulatory guidance to include older workers. Methods Regression analysis was used to derive new age-correction values using audiometric data from the 1999–2006 US NHANES. Using the NHANES median, better-ear thresholds fit to simple polynomial equations, new age-correction values were generated for both men and women for ages 20–75 years. Results The new age-correction values are presented as 2 options. The preferred option is to replace the current OSHA tables with the values derived from the NHANES median better-ear thresholds for ages 20–75 years. The alternative option is to retain the current OSHA age-correction values up to age 60 years and use the NHANES-based values for ages 61–75 years. Conclusions Recent NHANES data offer a simple solution to the need for updated, population-based, age-correction tables for OSHA. The options presented here provide scientifically valid and relevant age-correction values which can be easily adopted by

  16. Studies on the latitudinal distribution of ground-based geomagnetic pulsations and fluctuations in the interplanetary medium using discrete mathematical analysis methods

    NASA Astrophysics Data System (ADS)

    Zelinsky, N. R.; Kleimenova, N. G.; Malysheva, L. M.

    2014-07-01

    Ground-based geomagnetic Pc5 (2-7 mHz) pulsations, caused by the passage of dense transients (density disturbances) in the solar wind, were analyzed. It was shown that intensive bursts can appear in the density of the solar wind and its fluctuations, up to Np ˜ 30-50 cm3, even during the most magnetically calm year in the past decades (2009). The analysis, performed using one of the latest methods of discrete mathematical analysis (DMA), is presented. The energy functional of a time-series fragment (called "anomaly rectification" in DMA terms) of two such events was calculated. It was established that fluctuations in the dynamic pressure (density) of the solar wind (SW) cause the global excitation of Pc5 geomagnetic pulsations in the daytime sector of the Earth's magnetosphere, i.e., from polar to equatorial latitudes. Such pulsations started and ended suddenly and simultaneously at all latitudes. Fluctuations in the interplanetary magnetic field (IMF) have turned up to be less geoeffective in exciting geomagnetic pulsations than fluctuations in the SW density. The pulsation generation mechanisms in various structural regions of the magnetosphere were probably different. It was therefore concluded that the most probable source of ground-based pulsations are fluctuations of the corresponding periods in the SW density.

  17. Incorporating water table dynamics in climate modeling: 1. Water table observations and equilibrium water table simulations

    NASA Astrophysics Data System (ADS)

    Fan, Ying; Miguez-Macho, Gonzalo; Weaver, Christopher P.; Walko, Robert; Robock, Alan

    2007-05-01

    Soil moisture is a key participant in land-atmosphere interactions and an important determinant of terrestrial climate. In regions where the water table is shallow, soil moisture is coupled to the water table. This paper is the first of a two-part study to quantify this coupling and explore its implications in the context of climate modeling. We examine the observed water table depth in the lower 48 states of the United States in search of salient spatial and temporal features that are relevant to climate dynamics. As a means to interpolate and synthesize the scattered observations, we use a simple two-dimensional groundwater flow model to construct an equilibrium water table as a result of long-term climatic and geologic forcing. Model simulations suggest that the water table depth exhibits spatial organization at watershed, regional, and continental scales, which may have implications for the spatial organization of soil moisture at similar scales. The observations suggest that water table depth varies at diurnal, event, seasonal, and interannual scales, which may have implications for soil moisture memory at these scales.

  18. The study of RMB exchange rate complex networks based on fluctuation mode

    NASA Astrophysics Data System (ADS)

    Yao, Can-Zhong; Lin, Ji-Nan; Zheng, Xu-Zhou; Liu, Xiao-Feng

    2015-10-01

    In the paper, we research on the characteristics of RMB exchange rate time series fluctuation with methods of symbolization and coarse gaining. First, based on fluctuation features of RMB exchange rate, we define the first type of fluctuation mode as one specific foreign currency against RMB in four days' fluctuating situations, and the second type as four different foreign currencies against RMB in one day's fluctuating situation. With the transforming method, we construct the unique-currency and multi-currency complex networks. Further, through analyzing the topological features including out-degree, betweenness centrality and clustering coefficient of fluctuation-mode complex networks, we find that the out-degree distribution of both types of fluctuation mode basically follows power-law distributions with exponents between 1 and 2. The further analysis reveals that the out-degree and the clustering coefficient generally obey the approximated negative correlation. With this result, we confirm previous observations showing that the RMB exchange rate exhibits a characteristic of long-range memory. Finally, we analyze the most probable transmission route of fluctuation modes, and provide probability prediction matrix. The transmission route for RMB exchange rate fluctuation modes exhibits the characteristics of partially closed loop, repeat and reversibility, which lays a solid foundation for predicting RMB exchange rate fluctuation patterns with large volume of data.

  19. Detecting weak position fluctuations from encoder signal using singular spectrum analysis.

    PubMed

    Xu, Xiaoqiang; Zhao, Ming; Lin, Jing

    2017-11-01

    Mechanical fault or defect will cause some weak fluctuations to the position signal. Detection of such fluctuations via encoders can help determine the health condition and performance of the machine, and offer a promising alternative to the vibration-based monitoring scheme. However, besides the interested fluctuations, encoder signal also contains a large trend and some measurement noise. In applications, the trend is normally several orders larger than the concerned fluctuations in magnitude, which makes it difficult to detect the weak fluctuations without signal distortion. In addition, the fluctuations can be complicated and amplitude modulated under non-stationary working condition. To overcome this issue, singular spectrum analysis (SSA) is proposed for detecting weak position fluctuations from encoder signal in this paper. It enables complicated encode signal to be reduced into several interpretable components including a trend, a set of periodic fluctuations and noise. A numerical simulation is given to demonstrate the performance of the method, it shows that SSA outperforms empirical mode decomposition (EMD) in terms of capability and accuracy. Moreover, linear encoder signals from a CNC machine tool are analyzed to determine the magnitudes and sources of fluctuations during feed motion. The proposed method is proven to be feasible and reliable for machinery condition monitoring. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  20. Fluctuating volume-current formulation of electromagnetic fluctuations in inhomogeneous media: Incandescence and luminescence in arbitrary geometries

    NASA Astrophysics Data System (ADS)

    Polimeridis, Athanasios G.; Reid, M. T. H.; Jin, Weiliang; Johnson, Steven G.; White, Jacob K.; Rodriguez, Alejandro W.

    2015-10-01

    We describe a fluctuating volume-current formulation of electromagnetic fluctuations that extends our recent work on heat exchange and Casimir interactions between arbitrarily shaped homogeneous bodies [A. W. Rodriguez, M. T. H. Reid, and S. G. Johnson, Phys. Rev. B 88, 054305 (2013), 10.1103/PhysRevB.88.054305] to situations involving incandescence and luminescence problems, including thermal radiation, heat transfer, Casimir forces, spontaneous emission, fluorescence, and Raman scattering, in inhomogeneous media. Unlike previous scattering formulations based on field and/or surface unknowns, our work exploits powerful techniques from the volume-integral equation (VIE) method, in which electromagnetic scattering is described in terms of volumetric, current unknowns throughout the bodies. The resulting trace formulas (boxed equations) involve products of well-studied VIE matrices and describe power and momentum transfer between objects with spatially varying material properties and fluctuation characteristics. We demonstrate that thanks to the low-rank properties of the associated matrices, these formulas are susceptible to fast-trace computations based on iterative methods, making practical calculations tractable. We apply our techniques to study thermal radiation, heat transfer, and fluorescence in complicated geometries, checking our method against established techniques best suited for homogeneous bodies as well as applying it to obtain predictions of radiation from complex bodies with spatially varying permittivities and/or temperature profiles.

  1. iTTVis: Interactive Visualization of Table Tennis Data.

    PubMed

    Wu, Yingcai; Lan, Ji; Shu, Xinhuan; Ji, Chenyang; Zhao, Kejian; Wang, Jiachen; Zhang, Hui

    2018-01-01

    The rapid development of information technology paved the way for the recording of fine-grained data, such as stroke techniques and stroke placements, during a table tennis match. This data recording creates opportunities to analyze and evaluate matches from new perspectives. Nevertheless, the increasingly complex data poses a significant challenge to make sense of and gain insights into. Analysts usually employ tedious and cumbersome methods which are limited to watching videos and reading statistical tables. However, existing sports visualization methods cannot be applied to visualizing table tennis competitions due to different competition rules and particular data attributes. In this work, we collaborate with data analysts to understand and characterize the sophisticated domain problem of analysis of table tennis data. We propose iTTVis, a novel interactive table tennis visualization system, which to our knowledge, is the first visual analysis system for analyzing and exploring table tennis data. iTTVis provides a holistic visualization of an entire match from three main perspectives, namely, time-oriented, statistical, and tactical analyses. The proposed system with several well-coordinated views not only supports correlation identification through statistics and pattern detection of tactics with a score timeline but also allows cross analysis to gain insights. Data analysts have obtained several new insights by using iTTVis. The effectiveness and usability of the proposed system are demonstrated with four case studies.

  2. Pivot tables for mortality analysis, or who needs life tables anyway?

    PubMed

    Wesley, David; Cox, Hugh F

    2007-01-01

    Actuarial life-table analysis has long been used by life insurance medical directors for mortality abstraction from clinical studies. Ironically, today's life actuary instead uses pivot tables to analyze mortality. Pivot tables (a feature/function in MS Excel) collapse various dimensions of data that were previously arranged in an "experience study" format. Summary statistics such as actual deaths, actual and expected mortality (usually measured in dollars), and calculated results such as actual to expected ratios, are then displayed in a 2-dimensional grid. The same analytic process, excluding the dollar focus, can be used for clinical mortality studies. For raw survival data, especially large datasets, this combination of experience study data and pivot tables has clear advantages over life-table analysis in both accuracy and flexibility. Using the SEER breast cancer data, we compare the results of life-table analysis and pivot-table analysis.

  3. Automated edge finishing using an active XY table

    DOEpatents

    Loucks, Clifford S.; Starr, Gregory P.

    1993-01-01

    The disclosure is directed to an apparatus and method for automated edge finishing using hybrid position/force control of an XY table. The disclosure is particularly directed to learning the trajectory of the edge of a workpiece by "guarded moves". Machining is done by controllably moving the XY table, with the workpiece mounted thereon, along the learned trajectory with feedback from a force sensor. Other similar workpieces can be mounted, without a fixture on the XY table, located and the learned trajectory adjusted

  4. Free-Energy Fluctuations and Chaos in the Sherrington-Kirkpatrick Model

    NASA Astrophysics Data System (ADS)

    Aspelmeier, T.

    2008-03-01

    The sample-to-sample fluctuations ΔFN of the free-energy in the Sherrington-Kirkpatrick model are shown rigorously to be related to bond chaos. Via this connection, the fluctuations become analytically accessible by replica methods. The replica calculation for bond chaos shows that the exponent μ governing the growth of the fluctuations with system size N, ΔFN˜Nμ, is bounded by μ≤(1)/(4).

  5. The Application of LT-Table in TRIZ Contradiction Resolving Process

    NASA Astrophysics Data System (ADS)

    Wei, Zihui; Li, Qinghai; Wang, Donglin; Tian, Yumei

    TRIZ is used to resolve invention problems. ARIZ is the most powerful systematic method which integrates all of TRIZ heuristics. Definition of ideal final result (IFR), identification of contradictions and resource utilization are main lines of ARIZ. But resource searching of ARIZ has fault of blindness. Alexandr sets up mathematical model of transformation of the hereditary information in an invention problem using the theory of catastrophes, and provides method of resource searching using LT-table. The application of LT-table on contradiction resolving is introduced. Resource utilization using LT-table is joined into ARIZ step as an addition of TRIZ, apply this method in separator paper punching machine design.

  6. Report on computation of repetitive hyperbaric-hypobaric decompression tables

    NASA Technical Reports Server (NTRS)

    Edel, P. O.

    1975-01-01

    The tables were constructed specifically for NASA's simulated weightlessness training program; they provide for 8 depth ranges covering depths from 7 to 47 FSW, with exposure times of 15 to 360 minutes. These tables were based up on an 8 compartment model using tissue half-time values of 5 to 360 minutes and Workmanline M-values for control of the decompression obligation resulting from hyperbaric exposures. Supersaturation ratios of 1.55:1 to 2:1 were used for control of ascents to altitude following such repetitive dives. Adequacy of the method and the resultant tables were determined in light of past experience with decompression involving hyperbaric-hypobaric interfaces in human exposures. Using these criteria, the method showed conformity with empirically determined values. In areas where a discrepancy existed, the tables would err in the direction of safety.

  7. Adiabatic electron thermal pressure fluctuations in tokamak plasmas.

    PubMed

    Meier, M A; Bengtson, R D; Hallock, G A; Wootton, A J

    2001-08-20

    Electron thermal pressure fluctuations measured in the edge plasma of the Texas Experimental Tokamak Upgrade are a fundamental component of plasma turbulence on both sides of the velocity shear layer. The ratio of specific heats, estimated from fluctuations in electron temperature and electron number density measured simultaneously at the same electrode, indicates that observed fluctuations are adiabatic. The observations are made by means of a novel Langmuir probe technique, the time domain triple-probe method, which concurrently measures multiple plasma properties at each of two electrodes with the temporal and the spatial resolution required to estimate thermodynamic properties in a turbulent plasma.

  8. Sampling rare fluctuations of discrete-time Markov chains

    NASA Astrophysics Data System (ADS)

    Whitelam, Stephen

    2018-03-01

    We describe a simple method that can be used to sample the rare fluctuations of discrete-time Markov chains. We focus on the case of Markov chains with well-defined steady-state measures, and derive expressions for the large-deviation rate functions (and upper bounds on such functions) for dynamical quantities extensive in the length of the Markov chain. We illustrate the method using a series of simple examples, and use it to study the fluctuations of a lattice-based model of active matter that can undergo motility-induced phase separation.

  9. Sampling rare fluctuations of discrete-time Markov chains.

    PubMed

    Whitelam, Stephen

    2018-03-01

    We describe a simple method that can be used to sample the rare fluctuations of discrete-time Markov chains. We focus on the case of Markov chains with well-defined steady-state measures, and derive expressions for the large-deviation rate functions (and upper bounds on such functions) for dynamical quantities extensive in the length of the Markov chain. We illustrate the method using a series of simple examples, and use it to study the fluctuations of a lattice-based model of active matter that can undergo motility-induced phase separation.

  10. Fluctuating hydrodynamics of multispecies nonreactive mixtures

    DOE PAGES

    Balakrishnan, Kaushik; Garcia, Alejandro L.; Donev, Aleksandar; ...

    2014-01-22

    In this study we discuss the formulation of the fluctuating Navier-Stokes equations for multispecies, nonreactive fluids. In particular, we establish a form suitable for numerical solution of the resulting stochastic partial differential equations. An accurate and efficient numerical scheme, based on our previous methods for single species and binary mixtures, is presented and tested at equilibrium as well as for a variety of nonequilibrium problems. These include the study of giant nonequilibrium concentration fluctuations in a ternary mixture in the presence of a diffusion barrier, the triggering of a Rayleigh-Taylor instability by diffusion in a four-species mixture, as well asmore » reverse diffusion in a ternary mixture. Finally, good agreement with theory and experiment demonstrates that the formulation is robust and can serve as a useful tool in the study of thermal fluctuations for multispecies fluids.« less

  11. Nonconventional Methods in Teaching Matter, Atoms, Molecules and the Periodic Table for Nonmajor Students.

    ERIC Educational Resources Information Center

    Cherif, Abour A.; Adams, Gerald E.; Cannon, Charles E.

    1997-01-01

    Describes several activities used to teach students from middle school age to college nonmajors about the nature of matter, atoms, molecules and the periodic table. Strategies integrate such approaches as hands-on activities, visualization, writing, demonstrations, role play, and guided inquiry. For example, the periodic table is viewed as a town…

  12. Fluctuating asymmetry in broiler chickens: a decision protocol for trait selection in seven measuring methods.

    PubMed

    Van Nuffel, A; Tuyttens, F A M; Van Dongen, S; Talloen, W; Van Poucke, E; Sonck, B; Lens, L

    2007-12-01

    Nonidentical development of bilateral traits due to disturbing genetic or developmental factors is called fluctuating asymmetry (FA) if such deviations are continuously distributed. Fluctuating asymmetry is believed to be a reliable indicator of the fitness and welfare of an animal. Despite an increasing body of research, the link between FA and animal performance or welfare is reported to be inconsistent, possibly, among other reasons, due to inaccurate measuring protocols or incorrect statistical analyses. This paper reviews problems of interpreting FA results in poultry and provides guidelines for the measurement and analysis of FA, applied to broilers. A wide range of morphological traits were measured by 7 different techniques (ranging from measurements on living broilers or intact carcasses to X-rays, bones, and digital images) and evaluated for their applicability to estimate FA. Following 4 selection criteria (significant FA, absence of directional asymmetry or antisymmetry, absence of between-trait correlation in signed FA values, and high signal-to-noise ratio), from 3 to 14 measurements per method were found suitable for estimating the degree of FA. The accuracy of FA estimates was positively related to the complexity and time investment of the measuring method. In addition, our study clearly shows the importance of securing adequate statistical power when designing FA studies. Repeatability analyses of FA estimates indicated the need for larger sample sizes, more repeated measurements, or both, than are commonly used in FA studies.

  13. [The application of Delphi method in improving the score table for the hygienic quantifying and classification of hotels].

    PubMed

    Wang, Zi-yun; Liu, Yong-quan; Wang, Hong-bo; Zheng, Yang; Wu, Qi; Yang, Xia; Wu, Yong-wei; Zhao, Yi-ming

    2009-04-01

    By means of Delphi method and expert panel consultations, to choose suitable indicators and improve the score table for classifying the hygienic condition of hotels so that it can be widely used at nationwide. A two-round Delphi consultation was held to choose suitable indicators among 78 experts from 18 provinces, municipalities and autonomous regions. The suitable indicators were selected according to the importance recognized by experts. The average length of service in public health of the experts was (21.08 +/- 5.78) years and the average coefficient of experts' authorities C(r) was 0.89 +/- 0.07. The response rates of the two-round consultation were 98.72% (77/78) and 100.00% (77/77). The average feedback time were (8.49 +/- 4.48) d, (5.86 +/- 2.28) d, and the difference between two rounds was statistically significant (t = 4.60, P < 0.01). Kendall's coefficient were 0.26 (chi(2) = 723.63, P < 0.01), 0.32 (chi(2) = 635.65, P < 0.01) and opinions among experts became consistent. The score table for the hygienic quantifying and classification of hotels was composed of three first-class indicators (hygienic management, hygienic facilities and hygienic practices) and 36 second-class indicators. The weight coefficients of the three first-class indicators were 0.35, 0.34, 0.31. Delphi method might be used in a large-scale consultation among experts and be propitious to improve the score table for the hygienic quantifying and classification.

  14. Computing physical properties with quantum Monte Carlo methods with statistical fluctuations independent of system size.

    PubMed

    Assaraf, Roland

    2014-12-01

    We show that the recently proposed correlated sampling without reweighting procedure extends the locality (asymptotic independence of the system size) of a physical property to the statistical fluctuations of its estimator. This makes the approach potentially vastly more efficient for computing space-localized properties in large systems compared with standard correlated methods. A proof is given for a large collection of noninteracting fragments. Calculations on hydrogen chains suggest that this behavior holds not only for systems displaying short-range correlations, but also for systems with long-range correlations.

  15. 40 CFR Table C-2 to Subpart C of... - Sequence of Test Measurements

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 6 2013-07-01 2013-07-01 false Sequence of Test Measurements C Table C-2 to Subpart C of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Comparability Between Candidate Methods and Reference Methods Pt. 53, Subpt. C, Table C-2 Table C-2 to Subpart C...

  16. 40 CFR Table C-2 to Subpart C of... - Sequence of Test Measurements

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 6 2014-07-01 2014-07-01 false Sequence of Test Measurements C Table C-2 to Subpart C of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Comparability Between Candidate Methods and Reference Methods Pt. 53, Subpt. C, Table C-2 Table C-2 to Subpart C...

  17. 40 CFR Table C-2 to Subpart C of... - Sequence of Test Measurements

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 6 2012-07-01 2012-07-01 false Sequence of Test Measurements C Table C-2 to Subpart C of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Comparability Between Candidate Methods and Reference Methods Pt. 53, Subpt. C, Table C-2 Table C-2 to Subpart C...

  18. 40 CFR Table C-2 to Subpart C of... - Sequence of Test Measurements

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 5 2011-07-01 2011-07-01 false Sequence of Test Measurements C Table C-2 to Subpart C of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Comparability Between Candidate Methods and Reference Methods Pt. 53, Subpt. C, Table C-2 Table C-2 to Subpart C...

  19. 40 CFR Table C-2 to Subpart C of... - Sequence of Test Measurements

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Sequence of Test Measurements C Table C-2 to Subpart C of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Comparability Between Candidate Methods and Reference Methods Pt. 53, Subpt. C, Table C-2 Table C-2 to Subpart C...

  20. A shallow water table fluctuation model in response to precipitation with consideration of unsaturated gravitational flow

    NASA Astrophysics Data System (ADS)

    Park, E.; Jeong, J.

    2017-12-01

    A precise estimation of groundwater fluctuation is studied by considering delayed recharge flux (DRF) and unsaturated zone drainage (UZD). Both DRF and UZD are due to gravitational flow impeded in the unsaturated zone, which may nonnegligibly affect groundwater level changes. In the validation, a previous model without the consideration of unsaturated flow is benchmarked where the actual groundwater level and precipitation data are divided into three periods based on the climatic condition. The estimation capability of the new model is superior to the benchmarked model as indicated by the significantly improved representation of groundwater level with physically interpretable model parameters.

  1. Novel Hybrid Operating Table for Neuroendovascular Treatment.

    PubMed

    Jong-Hyun, Park; Jonghyeon, Mun; Dong-Seung, Shin; Bum-Tae, Kim

    2017-03-25

    The integration of interventional and surgical techniques is requiring the development of a new working environment equipped for the needs of an interdisciplinary neurovascular team. However, conventional surgical and interventional tables have only a limited ability to provide for these needs. We have developed a concept mobile hybrid operating table that provides the ability for such a team to conduct both endovascular and surgical procedures in a single session. We developed methods that provide surgeons with angiography-guided surgery techniques for use in a conventional operating room environment. In order to design a convenient device ideal for practical use, we consulted with mechanical engineers. The mobile hybrid operating table consists of two modules: a floating tabletop and a mobile module. In brief, the basic principle of the mobile hybrid operating table is as follows: firstly, the length of the mobile hybrid operating table is longer than that of a conventional surgical table and yet shorter than a conventional interventional table. It was designed with the goal of exhaustively meeting the intensive requirements of both endovascular and surgical procedures. Its mobile module allows for the floating tabletop to be moved quickly and precisely. It is important that during a procedure, a patient can be moved without being repositioned, particularly with a catheter in situ. Secondly, a slim-profile headrest facilitates the mounting of a radiolucent head cramp system for cranial stabilization and fixation. We have introduced a novel invention, a mobile hybrid operating table for use in an operating suite.

  2. A periodic table of coiled-coil protein structures.

    PubMed

    Moutevelis, Efrosini; Woolfson, Derek N

    2009-01-23

    Coiled coils are protein structure domains with two or more alpha-helices packed together via interlacing of side chains known as knob-into-hole packing. We analysed and classified a large set of coiled-coil structures using a combination of automated and manual methods. This led to a systematic classification that we termed a "periodic table of coiled coils," which we have made available at http://coiledcoils.chm.bris.ac.uk/ccplus/search/periodic_table. In this table, coiled-coil assemblies are arranged in columns with increasing numbers of alpha-helices and in rows of increased complexity. The table provides a framework for understanding possibilities in and limits on coiled-coil structures and a basis for future prediction, engineering and design studies.

  3. Accurate Evaluation Method of Molecular Binding Affinity from Fluctuation Frequency

    NASA Astrophysics Data System (ADS)

    Hoshino, Tyuji; Iwamoto, Koji; Ode, Hirotaka; Ohdomari, Iwao

    2008-05-01

    Exact estimation of the molecular binding affinity is significantly important for drug discovery. The energy calculation is a direct method to compute the strength of the interaction between two molecules. This energetic approach is, however, not accurate enough to evaluate a slight difference in binding affinity when distinguishing a prospective substance from dozens of candidates for medicine. Hence more accurate estimation of drug efficacy in a computer is currently demanded. Previously we proposed a concept of estimating molecular binding affinity, focusing on the fluctuation at an interface between two molecules. The aim of this paper is to demonstrate the compatibility between the proposed computational technique and experimental measurements, through several examples for computer simulations of an association of human immunodeficiency virus type-1 (HIV-1) protease and its inhibitor (an example for a drug-enzyme binding), a complexation of an antigen and its antibody (an example for a protein-protein binding), and a combination of estrogen receptor and its ligand chemicals (an example for a ligand-receptor binding). The proposed affinity estimation has proven to be a promising technique in the advanced stage of the discovery and the design of drugs.

  4. 40 CFR Table I-9 to Subpart I of... - Methods and Procedures for Conducting Emissions Test for Stack Systems

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Methods and Procedures for Conducting Emissions Test for Stack Systems I Table I-9 to Subpart I of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Electronics...

  5. The Star Schema Benchmark and Augmented Fact Table Indexing

    NASA Astrophysics Data System (ADS)

    O'Neil, Patrick; O'Neil, Elizabeth; Chen, Xuedong; Revilak, Stephen

    We provide a benchmark measuring star schema queries retrieving data from a fact table with Where clause column restrictions on dimension tables. Clustering is crucial to performance with modern disk technology, since retrievals with filter factors down to 0.0005 are now performed most efficiently by sequential table search rather than by indexed access. DB2’s Multi-Dimensional Clustering (MDC) provides methods to "dice" the fact table along a number of orthogonal "dimensions", but only when these dimensions are columns in the fact table. The diced cells cluster fact rows on several of these "dimensions" at once so queries restricting several such columns can access crucially localized data, with much faster query response. Unfortunately, columns of dimension tables of a star schema are not usually represented in the fact table. In this paper, we show a simple way to adjoin physical copies of dimension columns to the fact table, dicing data to effectively cluster query retrieval, and explain how such dicing can be achieved on database products other than DB2. We provide benchmark measurements to show successful use of this methodology on three commercial database products.

  6. A revised method for calculation of life expectancy tables from individual death records which provides increased accuracy at advanced ages.

    PubMed

    Mathisen, R W; Mazess, R B

    1981-02-01

    The authors present a revised method for calculating life expectancy tables for populations where individual ages at death are known or can be estimated. The conventional and revised methods are compared using data for U.S. and Hungarian males in an attempt to determine the accuracy of each method in calculating life expectancy at advanced ages. Means of correcting errors caused by age rounding, age exaggeration, and infant mortality are presented

  7. Links between climate change, water-table depth, and water chemistry in a mineralized mountain watershed

    USGS Publications Warehouse

    Manning, Andrew H.; Verplanck, Philip L.; Caine, Jonathan S.; Todd, Andrew S.

    2013-01-01

    Recent studies suggest that climate change is causing rising solute concentrations in mountain lakes and streams. These changes may be more pronounced in mineralized watersheds due to the sensitivity of sulfide weathering to changes in subsurface oxygen transport. Specific causal mechanisms linking climate change and accelerated weathering rates have been proposed, but in general remain entirely hypothetical. For mineralized watersheds, a favored hypothesis is that falling water tables caused by declining recharge rates allow an increasing volume of sulfide-bearing rock to become exposed to air, thus oxygen. Here, we test the hypothesis that falling water tables are the primary cause of an increase in metals and SO4 (100-400%) observed since 1980 in the Upper Snake River (USR), Colorado. The USR drains an alpine watershed geologically and climatologically representative of many others in mineralized areas of the western U.S. Hydrologic and chemical data collected from 2005 to 2011 in a deep monitoring well (WP1) at the top of the USR watershed are utilized. During this period, both water table depths and groundwater SO4 concentrations have generally increased in the well. A numerical model was constructed using TOUGHREACT that simulates pyrite oxidation near WP1, including groundwater flow and oxygen transport in both saturated and unsaturated zones. The modeling suggests that a falling water table could produce an increase in metals and SO4 of a magnitude similar to that observed in the USR (up to 300%). Future water table declines may produce limited increases in sulfide weathering high in the watershed because of the water table dropping below the depth of oxygen penetration, but may continue to enhance sulfide weathering lower in the watershed where water tables are shallower. Advective air (oxygen) transport in the unsaturated zone caused by seasonally variable recharge and associated water table fluctuations was found to have little influence on pyrite

  8. Brownian Motion with Active Fluctuations

    NASA Astrophysics Data System (ADS)

    Romanczuk, Pawel; Schimansky-Geier, Lutz

    2011-06-01

    We study the effect of different types of fluctuation on the motion of self-propelled particles in two spatial dimensions. We distinguish between passive and active fluctuations. Passive fluctuations (e.g., thermal fluctuations) are independent of the orientation of the particle. In contrast, active ones point parallel or perpendicular to the time dependent orientation of the particle. We derive analytical expressions for the speed and velocity probability density for a generic model of active Brownian particles, which yields an increased probability of low speeds in the presence of active fluctuations in comparison to the case of purely passive fluctuations. As a consequence, we predict sharply peaked Cartesian velocity probability densities at the origin. Finally, we show that such a behavior may also occur in non-Gaussian active fluctuations and discuss briefly correlations of the fluctuating stochastic forces.

  9. General method and thermodynamic tables for computation of equilibrium composition and temperature of chemical reactions

    NASA Technical Reports Server (NTRS)

    Huff, Vearl N; Gordon, Sanford; Morrell, Virginia E

    1951-01-01

    A rapidly convergent successive approximation process is described that simultaneously determines both composition and temperature resulting from a chemical reaction. This method is suitable for use with any set of reactants over the complete range of mixture ratios as long as the products of reaction are ideal gases. An approximate treatment of limited amounts of liquids and solids is also included. This method is particularly suited to problems having a large number of products of reaction and to problems that require determination of such properties as specific heat or velocity of sound of a dissociating mixture. The method presented is applicable to a wide variety of problems that include (1) combustion at constant pressure or volume; and (2) isentropic expansion to an assigned pressure, temperature, or Mach number. Tables of thermodynamic functions needed with this method are included for 42 substances for convenience in numerical computations.

  10. Tables for technical writers

    Treesearch

    E. vH. Larson

    1947-01-01

    Practically every publication we issue contains tables of some sort. Tables offer a convenient way of presenting many kinds of information. And tables are badly abused. There are few places a writer can go to find out how to construct clear, compact, easy-to-read tables, and how to use them.

  11. TableSeer: Automatic Table Extraction, Search, and Understanding

    ERIC Educational Resources Information Center

    Liu, Ying

    2009-01-01

    Tables are ubiquitous with a history that pre-dates that of sentential text. Authors often report a summary of their most important findings using tabular structure in documents. For example, scientists widely use tables to present the latest experimental results or statistical data in a condensed fashion. Along with the explosive development of…

  12. Determining the mean hydraulic gradient of ground water affected by tidal fluctuations

    USGS Publications Warehouse

    Serfes, Michael E.

    1991-01-01

    Tidal fluctuations in surface-water bodies produce progressive pressure waves in adjacent aquifers. As these pressure waves propagate inland, ground-water levels and hydraulic gradients continuously fluctuate, creating a situation where a single set of water-level measurements cannot be used to accurately characterize ground-water flow. For example, a time series of water levels measured in a confined aquifer in Atlantic City, New Jersey, showed that the hydraulic gradient ranged from .01 to .001 with a 22-degree change in direction during a tidal day of approximately 25 hours. At any point where ground water tidally fluctuates, the magnitude and direction of the hydraulic gradient fluctuates about the mean or regional hydraulic gradient. The net effect of these fluctuations on ground-water flow can be determined using the mean hydraulic gradient, which can be calculated by comparing mean ground- and surface-water elevations. Filtering methods traditionally used to determine daily mean sea level can be similarly applied to ground water to determine mean levels. Method (1) uses 71 consecutive hourly water-level observations to accurately determine the mean level. Method (2) approximates the mean level using only 25 consecutive hourly observations; however, there is a small error associated with this method.

  13. rSalvador: An R Package for the Fluctuation Experiment

    PubMed Central

    Zheng, Qi

    2017-01-01

    The past few years have seen a surge of novel applications of the Luria-Delbrück fluctuation assay protocol in bacterial research. Appropriate analysis of fluctuation assay data often requires computational methods that are unavailable in the popular web tool FALCOR. This paper introduces an R package named rSalvador to bring improvements to the field. The paper focuses on rSalvador’s capabilities to alleviate three kinds of problems found in recent investigations: (i) resorting to partial plating without properly accounting for the effects of partial plating; (ii) conducting attendant fitness assays without incorporating mutants’ relative fitness in subsequent data analysis; and (iii) comparing mutation rates using methods that are in general inapplicable to fluctuation assay data. In addition, the paper touches on rSalvador’s capabilities to estimate sample size and the difficulties related to parameter nonidentifiability. PMID:29084818

  14. The Dynamic Force Table

    ERIC Educational Resources Information Center

    Geddes, John B.; Black, Kelly

    2008-01-01

    We examine an experimental apparatus that is used to motivate the connections between the basic properties of vectors, potential functions, systems of nonlinear equations, and Newton's method for nonlinear systems of equations. The apparatus is an adaptation of a force table where we remove the center-pin and allow the center-ring to move freely.…

  15. Hot cell examination table

    DOEpatents

    Gaal, Peter S.; Ebejer, Lino P.; Kareis, James H.; Schlegel, Gary L.

    1991-01-01

    A table for use in a hot cell or similar controlled environment for use in examining specimens. The table has a movable table top that can be moved relative to a table frame. A shaft is fixedly mounted to the frame for axial rotation. A shaft traveler having a plurality of tilted rollers biased against the shaft is connected to the table top such that rotation of the shaft causes the shaft traveler to roll along the shaft. An electromagnetic drive is connected to the shaft and the frame for controllably rotating the shaft.

  16. Fluctuations of the flux of energy on the apparent horizon

    NASA Astrophysics Data System (ADS)

    Mimoso, José P.; Pavón, Diego

    2018-05-01

    Adopting the Landau-Lifshiftz method of classical fluctuations, we determine the statistical average strength of the fluctuations of the energy flux on the apparent horizon of a homogeneous and isotropic universe described by Einstein gravity. We find that the fluctuations increase with the temperature of the horizon and decrease with its area, in accordance with the features of systems where gravity can be neglected. We further find, on the one hand, that the fluctuations vanish in the cosmological constant dominated de Sitter expansion and, on the other hand, that the domination of phantom fields is excluded. The reasonableness of the results we have obtained lend support to the view that the Universe behaves as a normal thermodynamic system.

  17. Electron transfer statistics and thermal fluctuations in molecular junctions

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

    Goswami, Himangshu Prabal; Harbola, Upendra

    2015-02-28

    We derive analytical expressions for probability distribution function (PDF) for electron transport in a simple model of quantum junction in presence of thermal fluctuations. Our approach is based on the large deviation theory combined with the generating function method. For large number of electrons transferred, the PDF is found to decay exponentially in the tails with different rates due to applied bias. This asymmetry in the PDF is related to the fluctuation theorem. Statistics of fluctuations are analyzed in terms of the Fano factor. Thermal fluctuations play a quantitative role in determining the statistics of electron transfer; they tend tomore » suppress the average current while enhancing the fluctuations in particle transfer. This gives rise to both bunching and antibunching phenomena as determined by the Fano factor. The thermal fluctuations and shot noise compete with each other and determine the net (effective) statistics of particle transfer. Exact analytical expression is obtained for delay time distribution. The optimal values of the delay time between successive electron transfers can be lowered below the corresponding shot noise values by tuning the thermal effects.« less

  18. Eccentricity fluctuations are not the only source of elliptic flow fluctuations in a multiphase transport model

    NASA Astrophysics Data System (ADS)

    Xiao, Kai; Liu, Feng; Wang, Fu-Qiang

    2017-09-01

    Sources of event-by-event elliptic flow fluctuations in relativistic heavy-ion collisions are investigated in a multiphase parton transport model (AMPT). Besides the well-known initial eccentricity fluctuations, several other sources of elliptic flow dynamical fluctuations are identified. One is fluctuations in initial parton configurations at a given eccentricity. Configuration fluctuations are found to be as important as eccentricity fluctuations in elliptic flow development. A second is quantum fluctuations in parton-parton interactions during system evolution. A third is fluctuations caused by hadronization and final-state hadronic scatterings. The magnitudes of these fluctuations are investigated relative to the eccentricity fluctuations and the average elliptic flow magnitude. The fluctuations from the latter two sources are found to be negative. The results may have important implications for the interpretation of elliptic flow data. Supported by MOST, China, under 973 Grant 2015CB856901, National Natural Science Foundation of China (11521064, 11547143, 11228513), U.S. Department of Energy (DE-FG02-88ER40412), Fundamental Research Funds for the Central Universities, South-Central University for Nationalities (CZQ15001) and Excellent Doctorial Dissertation Cultivation Grant from Central China Normal University (2013YBZD18)

  19. Correlations of stock price fluctuations under multi-scale and multi-threshold scenarios

    NASA Astrophysics Data System (ADS)

    Sui, Guo; Li, Huajiao; Feng, Sida; Liu, Xueyong; Jiang, Meihui

    2018-01-01

    The multi-scale method is widely used in analyzing time series of financial markets and it can provide market information for different economic entities who focus on different periods. Through constructing multi-scale networks of price fluctuation correlation in the stock market, we can detect the topological relationship between each time series. Previous research has not addressed the problem that the original fluctuation correlation networks are fully connected networks and more information exists within these networks that is currently being utilized. Here we use listed coal companies as a case study. First, we decompose the original stock price fluctuation series into different time scales. Second, we construct the stock price fluctuation correlation networks at different time scales. Third, we delete the edges of the network based on thresholds and analyze the network indicators. Through combining the multi-scale method with the multi-threshold method, we bring to light the implicit information of fully connected networks.

  20. Vibration signal correction of unbalanced rotor due to angular speed fluctuation

    NASA Astrophysics Data System (ADS)

    Cao, Hongrui; He, Dong; Xi, Songtao; Chen, Xuefeng

    2018-07-01

    The rotating speed of a rotor is hardly constant in practice due to angular speed fluctuation, which affects the balancing accuracy of the rotor. In this paper, the effect of angular speed fluctuation on vibration responses of the unbalanced rotor is analyzed quantitatively. Then, a vibration signal correction method based on zoom synchrosqueezing transform (ZST) and tacholess order tracking is proposed. The instantaneous angular speed (IAS) of the rotor is extracted by the ZST firstly and then used to calculate the instantaneous phase. The vibration signal is further resampled in angular domain to reduce the effect of angular speed fluctuation. The signal obtained in angular domain is transformed into order domain using discrete Fourier transform (DFT) to estimate the amplitude and phase of the vibration signal. Simulated and experimental results show that the proposed method can successfully correct the amplitude and phase of the vibration signal due to angular speed fluctuation.

  1. A study on suppressing transmittance fluctuations for air-gapped Glan-type polarizing prisms

    NASA Astrophysics Data System (ADS)

    Zhang, Chuanfa; Li, Dailin; Zhu, Huafeng; Li, Chuanzhi; Jiao, Zhiyong; Wang, Ning; Xu, Zhaopeng; Wang, Xiumin; Song, Lianke

    2018-05-01

    Light intensity transmittance is a key parameter for the design of polarizing prisms, while sometimes its experimental curves based on spatial incident angle presents periodical fluctuations. Here, we propose a novel method for completely suppressing these fluctuations via setting a glued error angle in the air gap of Glan-Taylor prisms. The proposal consists of: an accurate formula of the intensity transmittance for Glan-Taylor prisms, a numerical simulation and a contrast experiment of Glan-Taylor prisms for analyzing the causes of the fluctuations, and a simple method for accurately measuring the glued error angle. The result indicates that when the setting glued error angle is larger than the critical angle for a certain polarizing prism, the fluctuations can be completely suppressed, and a smooth intensity transmittance curve can be obtained. Besides, the critical angle in the air gap for suppressing the fluctuations is decreased with the increase of beam spot size. This method has the advantage of having less demand for the prism position in optical systems.

  2. Mechanical energy fluctuations in granular chains: the possibility of rogue fluctuations or waves.

    PubMed

    Han, Ding; Westley, Matthew; Sen, Surajit

    2014-09-01

    The existence of rogue or freak waves in the ocean has been known for some time. They have been reported in the context of optical lattices and the financial market. We ask whether such waves are generic to late time behavior in nonlinear systems. In that vein, we examine the dynamics of an alignment of spherical elastic beads held within fixed, rigid walls at zero precompression when they are subjected to sufficiently rich initial conditions. Here we define such waves generically as unusually large energy fluctuations that sustain for short periods of time. Our simulations suggest that such unusually large fluctuations ("hot spots") and occasional series of such fluctuations through space and time ("rogue fluctuations") are likely to exist in the late time dynamics of the granular chain system at zero dissipation. We show that while hot spots are common in late time evolution, rogue fluctuations are seen in purely nonlinear systems (i.e., no precompression) at late enough times. We next show that the number of such fluctuations grows exponentially with increasing nonlinearity whereas rogue fluctuations decrease superexponentially with increasing precompression. Dissipation-free granular alignment systems may be possible to realize as integrated circuits and hence our observations may potentially be testable in the laboratory.

  3. Fluctuation scaling in the visual cortex at threshold

    NASA Astrophysics Data System (ADS)

    Medina, José M.; Díaz, José A.

    2016-05-01

    Fluctuation scaling relates trial-to-trial variability to the average response by a power function in many physical processes. Here we address whether fluctuation scaling holds in sensory psychophysics and its functional role in visual processing. We report experimental evidence of fluctuation scaling in human color vision and form perception at threshold. Subjects detected thresholds in a psychophysical masking experiment that is considered a standard reference for studying suppression between neurons in the visual cortex. For all subjects, the analysis of threshold variability that results from the masking task indicates that fluctuation scaling is a global property that modulates detection thresholds with a scaling exponent that departs from 2, β =2.48 ±0.07 . We also examine a generalized version of fluctuation scaling between the sample kurtosis K and the sample skewness S of threshold distributions. We find that K and S are related and follow a unique quadratic form K =(1.19 ±0.04 ) S2+(2.68 ±0.06 ) that departs from the expected 4/3 power function regime. A random multiplicative process with weak additive noise is proposed based on a Langevin-type equation. The multiplicative process provides a unifying description of fluctuation scaling and the quadratic S -K relation and is related to on-off intermittency in sensory perception. Our findings provide an insight into how the human visual system interacts with the external environment. The theoretical methods open perspectives for investigating fluctuation scaling and intermittency effects in a wide variety of natural, economic, and cognitive phenomena.

  4. Charge fluctuations in nanoscale capacitors.

    PubMed

    Limmer, David T; Merlet, Céline; Salanne, Mathieu; Chandler, David; Madden, Paul A; van Roij, René; Rotenberg, Benjamin

    2013-09-06

    The fluctuations of the charge on an electrode contain information on the microscopic correlations within the adjacent fluid and their effect on the electronic properties of the interface. We investigate these fluctuations using molecular dynamics simulations in a constant-potential ensemble with histogram reweighting techniques. This approach offers, in particular, an efficient, accurate, and physically insightful route to the differential capacitance that is broadly applicable. We demonstrate these methods with three different capacitors: pure water between platinum electrodes and a pure as well as a solvent-based organic electrolyte each between graphite electrodes. The total charge distributions with the pure solvent and solvent-based electrolytes are remarkably Gaussian, while in the pure ionic liquid the total charge distribution displays distinct non-Gaussian features, suggesting significant potential-driven changes in the organization of the interfacial fluid.

  5. Charge Fluctuations in Nanoscale Capacitors

    NASA Astrophysics Data System (ADS)

    Limmer, David T.; Merlet, Céline; Salanne, Mathieu; Chandler, David; Madden, Paul A.; van Roij, René; Rotenberg, Benjamin

    2013-09-01

    The fluctuations of the charge on an electrode contain information on the microscopic correlations within the adjacent fluid and their effect on the electronic properties of the interface. We investigate these fluctuations using molecular dynamics simulations in a constant-potential ensemble with histogram reweighting techniques. This approach offers, in particular, an efficient, accurate, and physically insightful route to the differential capacitance that is broadly applicable. We demonstrate these methods with three different capacitors: pure water between platinum electrodes and a pure as well as a solvent-based organic electrolyte each between graphite electrodes. The total charge distributions with the pure solvent and solvent-based electrolytes are remarkably Gaussian, while in the pure ionic liquid the total charge distribution displays distinct non-Gaussian features, suggesting significant potential-driven changes in the organization of the interfacial fluid.

  6. A novel HTS magnetic levitation dining table

    NASA Astrophysics Data System (ADS)

    Lu, Yiyun; Huang, Huiying

    2018-05-01

    High temperature superconducting (HTS) bulk can levitate above or suspend below a permanent magnet stably. Many magnificent potential applications of HTS bulk are proposed by researchers. Until now, few reports have been found for real applications of HTS bulk. A complete set of small-scale HTS magnetic levitation table is proposed in the paper. The HTS magnetic levitation table includes an annular HTS magnetic levitation system which is composed of an annular HTS bulk array and an annular permanent magnet guideway (PMG). The annular PMG and the annular cryogenics vessel which used to maintain low temperature environment of the HTS bulk array are designed. 62 YBCO bulks are used to locate at the bottom of the annular vessel. A 3D-model finite element numerical method is used to design the HTS bulk magnetic levitation system. Equivalent magnetic levitation and guidance forces calculation rules are proposed aimed at the annular HTS magnetic levitation system stability. Based on the proposed method, levitation and guidance forces curves of the one YBCO bulk magnetic above PMG could be obtained. This method also can use to assist PMG design to check whether the designed PMG could reach the basic demand of the HTS magnetic levitation table.

  7. Plasma fluctuations as Markovian noise.

    PubMed

    Li, B; Hazeltine, R D; Gentle, K W

    2007-12-01

    Noise theory is used to study the correlations of stationary Markovian fluctuations that are homogeneous and isotropic in space. The relaxation of the fluctuations is modeled by the diffusion equation. The spatial correlations of random fluctuations are modeled by the exponential decay. Based on these models, the temporal correlations of random fluctuations, such as the correlation function and the power spectrum, are calculated. We find that the diffusion process can give rise to the decay of the correlation function and a broad frequency spectrum of random fluctuations. We also find that the transport coefficients may be estimated by the correlation length and the correlation time. The theoretical results are compared with the observed plasma density fluctuations from the tokamak and helimak experiments.

  8. Fluctuating Thermodynamics for Biological Processes

    NASA Astrophysics Data System (ADS)

    Ham, Sihyun

    Because biomolecular processes are largely under thermodynamic control, dynamic extension of thermodynamics is necessary to uncover the mechanisms and driving factors of fluctuating processes. The fluctuating thermodynamics technology presented in this talk offers a practical means for the thermodynamic characterization of conformational dynamics in biomolecules. The use of fluctuating thermodynamics has the potential to provide a comprehensive picture of fluctuating phenomena in diverse biological processes. Through the application of fluctuating thermodynamics, we provide a thermodynamic perspective on the misfolding and aggregation of the various proteins associated with human diseases. In this talk, I will present the detailed concepts and applications of the fluctuating thermodynamics technology for elucidating biological processes. This work was supported by Samsung Science and Technology Foundation under Project Number SSTF-BA1401-13.

  9. Giant current fluctuations in an overheated single-electron transistor

    NASA Astrophysics Data System (ADS)

    Laakso, M. A.; Heikkilä, T. T.; Nazarov, Yuli V.

    2010-11-01

    Interplay of cotunneling and single-electron tunneling in a thermally isolated single-electron transistor leads to peculiar overheating effects. In particular, there is an interesting crossover interval where the competition between cotunneling and single-electron tunneling changes to the dominance of the latter. In this interval, the current exhibits anomalous sensitivity to the effective electron temperature of the transistor island and its fluctuations. We present a detailed study of the current and temperature fluctuations at this interesting point. The methods implemented allow for a complete characterization of the distribution of the fluctuating quantities, well beyond the Gaussian approximation. We reveal and explore the parameter range where, for sufficiently small transistor islands, the current fluctuations become gigantic. In this regime, the optimal value of the current, its expectation value, and its standard deviation differ from each other by parametrically large factors. This situation is unique for transport in nanostructures and for electron transport in general. The origin of this spectacular effect is the exponential sensitivity of the current to the fluctuating effective temperature.

  10. Stochastic estimation of plant-available soil water under fluctuating water table depths

    NASA Astrophysics Data System (ADS)

    Or, Dani; Groeneveld, David P.

    1994-12-01

    Preservation of native valley-floor phreatophytes while pumping groundwater for export from Owens Valley, California, requires reliable predictions of plant water use. These predictions are compared with stored soil water within well field regions and serve as a basis for managing groundwater resources. Soil water measurement errors, variable recharge, unpredictable climatic conditions affecting plant water use, and modeling errors make soil water predictions uncertain and error-prone. We developed and tested a scheme based on soil water balance coupled with implementation of Kalman filtering (KF) for (1) providing physically based soil water storage predictions with prediction errors projected from the statistics of the various inputs, and (2) reducing the overall uncertainty in both estimates and predictions. The proposed KF-based scheme was tested using experimental data collected at a location on the Owens Valley floor where the water table was artificially lowered by groundwater pumping and later allowed to recover. Vegetation composition and per cent cover, climatic data, and soil water information were collected and used for developing a soil water balance. Predictions and updates of soil water storage under different types of vegetation were obtained for a period of 5 years. The main results show that: (1) the proposed predictive model provides reliable and resilient soil water estimates under a wide range of external conditions; (2) the predicted soil water storage and the error bounds provided by the model offer a realistic and rational basis for decisions such as when to curtail well field operation to ensure plant survival. The predictive model offers a practical means for accommodating simple aspects of spatial variability by considering the additional source of uncertainty as part of modeling or measurement uncertainty.

  11. Multiple-methods investigation of recharge at a humid-region fractured rock site, Pennsylvania, USA

    USGS Publications Warehouse

    Heppner, C.S.; Nimmo, J.R.; Folmar, G.J.; Gburek, W.J.; Risser, D.W.

    2007-01-01

    Lysimeter-percolate and well-hydrograph analyses were combined to evaluate recharge for the Masser Recharge Site (central Pennsylvania, USA). In humid regions, aquifer recharge through an unconfined low-porosity fractured-rock aquifer can cause large magnitude water-table fluctuations over short time scales. The unsaturated hydraulic characteristics of the subsurface porous media control the magnitude and timing of these fluctuations. Data from multiple sets of lysimeters at the site show a highly seasonal pattern of percolate and exhibit variability due to both installation factors and hydraulic property heterogeneity. Individual event analysis of well hydrograph data reveals the primary influences on water-table response, namely rainfall depth, rainfall intensity, and initial water-table depth. Spatial and seasonal variability in well response is also evident. A new approach for calculating recharge from continuous water-table elevation records using a master recession curve (MRC) is demonstrated. The recharge estimated by the MRC approach when assuming a constant specific yield is seasonal to a lesser degree than the recharge estimate resulting from the lysimeter analysis. Partial reconciliation of the two recharge estimates is achieved by considering a conceptual model of flow processes in the highly-heterogeneous underlying fractured porous medium. ?? Springer-Verlag 2007.

  12. Fast mix table construction for material discretization

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

    Johnson, S. R.

    2013-07-01

    An effective hybrid Monte Carlo-deterministic implementation typically requires the approximation of a continuous geometry description with a discretized piecewise-constant material field. The inherent geometry discretization error can be reduced somewhat by using material mixing, where multiple materials inside a discrete mesh voxel are homogenized. Material mixing requires the construction of a 'mix table,' which stores the volume fractions in every mixture so that multiple voxels with similar compositions can reference the same mixture. Mix table construction is a potentially expensive serial operation for large problems with many materials and voxels. We formulate an efficient algorithm to construct a sparse mixmore » table in O(number of voxels x log number of mixtures) time. The new algorithm is implemented in ADVANTG and used to discretize continuous geometries onto a structured Cartesian grid. When applied to an end-of-life MCNP model of the High Flux Isotope Reactor with 270 distinct materials, the new method improves the material mixing time by a factor of 100 compared to a naive mix table implementation. (authors)« less

  13. Fast Mix Table Construction for Material Discretization

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

    Johnson, Seth R

    2013-01-01

    An effective hybrid Monte Carlo--deterministic implementation typically requires the approximation of a continuous geometry description with a discretized piecewise-constant material field. The inherent geometry discretization error can be reduced somewhat by using material mixing, where multiple materials inside a discrete mesh voxel are homogenized. Material mixing requires the construction of a ``mix table,'' which stores the volume fractions in every mixture so that multiple voxels with similar compositions can reference the same mixture. Mix table construction is a potentially expensive serial operation for large problems with many materials and voxels. We formulate an efficient algorithm to construct a sparse mix table inmore » $$O(\\text{number of voxels}\\times \\log \\text{number of mixtures})$$ time. The new algorithm is implemented in ADVANTG and used to discretize continuous geometries onto a structured Cartesian grid. When applied to an end-of-life MCNP model of the High Flux Isotope Reactor with 270 distinct materials, the new method improves the material mixing time by a factor of 100 compared to a naive mix table implementation.« less

  14. Hierarchical structure of stock price fluctuations in financial markets

    NASA Astrophysics Data System (ADS)

    Gao, Ya-Chun; Cai, Shi-Min; Wang, Bing-Hong

    2012-12-01

    The financial market and turbulence have been broadly compared on account of the same quantitative methods and several common stylized facts they share. In this paper, the She-Leveque (SL) hierarchy, proposed to explain the anomalous scaling exponents deviating from Kolmogorov monofractal scaling of the velocity fluctuation in fluid turbulence, is applied to study and quantify the hierarchical structure of stock price fluctuations in financial markets. We therefore observed certain interesting results: (i) the hierarchical structure related to multifractal scaling generally presents in all the stock price fluctuations we investigated. (ii) The quantitatively statistical parameters that describe SL hierarchy are different between developed financial markets and emerging ones, distinctively. (iii) For the high-frequency stock price fluctuation, the hierarchical structure varies with different time periods. All these results provide a novel analogy in turbulence and financial market dynamics and an insight to deeply understand multifractality in financial markets.

  15. Fluctuations in Cerebral Hemodynamics

    DTIC Science & Technology

    2003-12-01

    Determination of scaling properties Detrended Fluctuations Analysis (see (28) and references therein) is commonly used to determine scaling...pressure (averaged over a cardiac beat) of a healthy subject. First 1000 values of the time series are shown. (b) Detrended fluctuation analysis (DFA...1000 values of the time series are shown. (b) Detrended fluctuation analysis of the time series shown in (a). Fig . 3 Side-by-side boxplot for the

  16. Perceived Treatment Status of Fluctuations in Parkinson Disease Impacts Suicidality.

    PubMed

    Hinkle, Jared T; Perepezko, Kate; Mari, Zoltan; Marsh, Laura; Pontone, Gregory M

    2018-01-31

    On/off motor fluctuations in Parkinson disease (PD) can be associated with extreme mood fluctuations and severe dysphoria. The impact of these affective symptoms may be overlooked in the treatment of motor fluctuations. Our goal was to examine the relationship between motor fluctuations, their treatment status, and suicidality in PD participants. We analyzed data from the Methods of Optimal Depression Detection in Parkinson's Disease (MOOD-PD) study of 223 individuals with PD. Suicidality was measured using items from four depression scales: Hamilton Depression Rating Scale (HAM-D-17); Montgomery-Åsberg Depression Rating Scale (MADRS); Inventory for Depressive Symptomatology (IDS-C); and the self-rated Beck Depression Inventory (BDI). Multivariable Poisson regression analyses tested whether self-reported motor fluctuations and their treatment status were associated with suicidality while controlling for recognized risk factors. Thirty-seven participants (16.6%) self-reported suicidality and 89 (39.5%) self-reported motor fluctuations, of whom 21 (23.6%) perceived their fluctuations as untreated. Participants reporting untreated motor fluctuations more frequently had a current depressive disorder (p < 0.001) and endorsed suicidality (p = 0.006) than participants with treated or no fluctuations. They also had significantly higher total scores on the HAM-D-17, MADRS, IDS-C, and BDI depression scales (p < 0.001 for each). Regression analyses showed significant associations between untreated motor fluctuations and higher scores on suicide questions extracted from the HAM-D-17, MADRS, and IDS-C (p < 0.01 for each). PD patients with untreated motor fluctuations are at increased risk for suicidal thoughts and should be monitored for mood changes as treatment is adapted. Copyright © 2018 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

  17. Wetland Resiliency: How does multi-year water table level decline and recovery influence carbon dioxide and methane fluxes?

    NASA Astrophysics Data System (ADS)

    Pugh, C.; Reed, D. E.; Desai, A. R.; Sulman, B. N.

    2016-12-01

    Wetlands play a disproportionately large role in the global carbon budget, and individual wetlands can fluctuate between carbon sinks and sources depending on factors such as hydrology, biogeochemistry, and land use. Although much research has been done on wetland biogeochemical cycles, there is a lack of experimental evidence concerning how changes in wetland hydrology influence these cycles over interannual timescales. Over a seven-year period, Sulman et al. (2009) found that a drought-induced declining water table at a shrub wetland in northern Wisconsin coincided with increased ecosystem respiration (ER) and gross ecosystem productivity (GEP) (Sulman et al. 2009). Since then, however, the average water table level at this site has begun to increase, thus allowing a unique opportunity to explore how wetland carbon storage is impacted by water table recovery. With the addition of three more years of eddy covariance observations post recovery and new methane flux observations, we found that water table level no longer had a significant correlation with GEP, ER, or methane flux. Air temperature, however, had a strong correlation with all three. Average methane flux stayed relatively constant under 14 °C, before increasing an order of magnitude from 3.7 nmol m-2 s-1 in April to 36 nmol m-2 s-1 in July. These results suggest that, over decadal timescales, temperature, rather than water level, is a stronger limiting factor for both aerobic and anaerobic respiration in shrub fen wetlands. Wetlands play a disproportionately large role in the global carbon budget, and individual wetlands can fluctuate between carbon sinks and sources depending on factors such as hydrology, biogeochemistry, and land use. Although much research has been done on wetland biogeochemical cycles, there is a lack of experimental evidence concerning how changes in wetland hydrology influence these cycles over interannual timescales. Over a seven-year period, Sulman et al. (2009) found that a

  18. Table-top job analysis

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

    Not Available

    1994-12-01

    The purpose of this Handbook is to establish general training program guidelines for training personnel in developing training for operation, maintenance, and technical support personnel at Department of Energy (DOE) nuclear facilities. TTJA is not the only method of job analysis; however, when conducted properly TTJA can be cost effective, efficient, and self-validating, and represents an effective method of defining job requirements. The table-top job analysis is suggested in the DOE Training Accreditation Program manuals as an acceptable alternative to traditional methods of analyzing job requirements. DOE 5480-20A strongly endorses and recommends it as the preferred method for analyzing jobsmore » for positions addressed by the Order.« less

  19. Quantum dynamics in strong fluctuating fields

    NASA Astrophysics Data System (ADS)

    Goychuk, Igor; Hänggi, Peter

    A large number of multifaceted quantum transport processes in molecular systems and physical nanosystems, such as e.g. nonadiabatic electron transfer in proteins, can be treated in terms of quantum relaxation processes which couple to one or several fluctuating environments. A thermal equilibrium environment can conveniently be modelled by a thermal bath of harmonic oscillators. An archetype situation provides a two-state dissipative quantum dynamics, commonly known under the label of a spin-boson dynamics. An interesting and nontrivial physical situation emerges, however, when the quantum dynamics evolves far away from thermal equilibrium. This occurs, for example, when a charge transferring medium possesses nonequilibrium degrees of freedom, or when a strong time-dependent control field is applied externally. Accordingly, certain parameters of underlying quantum subsystem acquire stochastic character. This may occur, for example, for the tunnelling coupling between the donor and acceptor states of the transferring electron, or for the corresponding energy difference between electronic states which assume via the coupling to the fluctuating environment an explicit stochastic or deterministic time-dependence. Here, we review the general theoretical framework which is based on the method of projector operators, yielding the quantum master equations for systems that are exposed to strong external fields. This allows one to investigate on a common basis, the influence of nonequilibrium fluctuations and periodic electrical fields on those already mentioned dynamics and related quantum transport processes. Most importantly, such strong fluctuating fields induce a whole variety of nonlinear and nonequilibrium phenomena. A characteristic feature of such dynamics is the absence of thermal (quantum) detailed balance.ContentsPAGE1. Introduction5262. Quantum dynamics in stochastic fields531 2.1. Stochastic Liouville equation531 2.2. Non-Markovian vs. Markovian discrete

  20. Kepler Certified False Positive Table

    NASA Technical Reports Server (NTRS)

    Bryson, Stephen T.; Batalha, Natalie Marie; Colon, Knicole Dawn; Coughlin, Jeffrey Langer; Haas, Michael R.; Henze, Chris; Huber, Daniel; Morton, Tim; Rowe, Jason Frank; Mullally, Susan Elizabeth; hide

    2017-01-01

    This document describes the Kepler Certied False Positive table hosted at the Exoplanet Archive1, herein referred to as the CFP table. This table is the result of detailed examination by the Kepler False Positive Working Group (FPWG) of declared false positives in the Kepler Object of Interest (KOI) tables (see, for example, Batalha et al. (2012); Burke et al.(2014); Rowe et al. (2015); Mullally et al. (2015); Coughlin et al. (2015b)) at the Exoplanet Archive. A KOI is considered a false positive if it is not due to a planet orbiting the KOI's target star. The CFP table contains all KOIs in the Exoplanet Archive cumulative KOI table. The purpose of the CFP table is to provide a list of certified false positive KOIs. A KOI is certified as a false positive when, in the judgement of the FPWG, there is no plausible planetary interpretation of the observational evidence, which we summarize by saying that the evidence for a false positive is compelling. This certification process involves detailed examination using all available data for each KOI, establishing a high-reliability ground truth set. The CFP table can be used to estimate the reliability of, for example, the KOI tables which are created using only Kepler photometric data, so the disposition of individual KOIs may differ in the KOI and CFP tables. Follow-up observers may find the CFP table useful to avoid observing false positives.

  1. 47 CFR 73.698 - Tables.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Tables. 73.698 Section 73.698 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Television Broadcast Stations § 73.698 Tables. Table I [Reserved] Table II (1)—Channel (2)—31.4 kilometers (19.5 miles...

  2. Fluctuation solution theory of pure fluids

    NASA Astrophysics Data System (ADS)

    Ploetz, Elizabeth A.; Pallewela, Gayani N.; Smith, Paul E.

    2017-03-01

    Fluctuation Solution Theory (FST) provides an alternative view of fluid thermodynamics in terms of pair fluctuations in the particle number and excess energy observed for an equivalent open system. Here we extend the FST approach to provide a series of triplet and quadruplet particle and excess energy fluctuations that can also be used to help understand the behavior of fluids. The fluctuations for the gas, liquid, and supercritical regions of three fluids (H2O, CO2, and SF6) are then determined from accurate equations of state. Many of the fluctuating quantities change sign on moving from the gas to liquid phase and, therefore, we argue that the fluctuations can be used to characterize gas and liquid behavior. Further analysis provides an approach to isolate contributions to the excess energy fluctuations arising from just the intermolecular interactions and also indicates that the triplet and quadruplet particle fluctuations are related to the pair particle fluctuations by a simple power law for large regions of the phase diagram away from the critical point.

  3. Periodic Table of Students.

    ERIC Educational Resources Information Center

    Johnson, Mike

    1998-01-01

    Presents an exercise in which an eighth-grade science teacher decorated the classroom with a periodic table of students. Student photographs were arranged according to similarities into vertical columns. Students were each assigned an atomic number according to their placement in the table. The table is then used to teach students about…

  4. Manipulative lowering of the water table during summer does not affect CO2 emissions and uptake in a fen in Germany.

    PubMed

    Muhr, Jan; Höhle, Juliane; Otieno, Dennis O; Borken, Werner

    2011-03-01

    We simulated the effect of prolonged dry summer periods by lowering the water table on three manipulation plots (D(1-3)) in a minerotrophic fen in southeastern Germany in three years (2006-2008). The water table at this site was lowered by drainage and by excluding precipitation; three nonmanipulated control plots (C(1-3)) served as a reference. We found no significant differences in soil respiration (R(Soil)), gross primary production (GPP), or aboveground respiration (R(AG)) between the C(1-3) and D(1-3) plots in any of the measurement years. The water table on the control plots was naturally low, with a median water table (2006-2008) of 8 cm below the surface, and even lower during summer when respiratory activity was highest, with median values (C(1-3)) between 11 and 19 cm below the surface. If it is assumed that oxygen availability in the uppermost 10 cm was not limited by the location of the water table, manipulative lowering of the water table most likely increased oxygen availability only in deeper peat layers where we expect R(Soil) to be limited by poor substrate quality rather than anoxia. This could explain the lack of a manipulation effect. In a second approach, we estimated the influence of the water table on R(Soil) irrespective of treatment. The results showed a significant correlation between R(Soil) and water table, but with R(Soil) decreasing at lower water tables rather than increasing. We thus conclude that decomposition in the litter layer is not limited by waterlogging in summer, and deeper peat layers bear no significant decomposition potential due to poor substrate quality. Consequently, we do not expect enhanced C losses from this site due to increasing frequency of dry summers. Assimilation and respiration of aboveground vegetation were not affected by water table fluctuations between 10 and >60 cm depth, indicating the lack of stress resulting from either anoxia (high water table) or drought (low water table).

  5. The relation between skin friction fluctuations and turbulent fluctuating velocities in turbulent boundary layers

    NASA Astrophysics Data System (ADS)

    Diaz Daniel, Carlos; Laizet, Sylvain; Vassilicos, John Christos

    2015-11-01

    The Townsend-Perry hypothesis of wall-attached eddies relates the friction velocity uτ at the wall to velocity fluctuations at a position y from the wall, resulting in a wavenumber range where the streamwise fluctuating velocity spectrum scales as E (k) ~k-1 and the corresponding structure function scales as uτ2 in the corresponding length-scale range. However, this model does not take in account the fluctuations of the skin friction velocity, which are in fact strongly intermittent. A DNS of zero-pressure gradient turbulent boundary layer suggests a 10 to 15 degree angle from the lag of the peak in the cross-correlations between the fluctuations of the shear stress and streamwise fluctuating velocities at different heights in the boundary layer. Using this result, it is possible to refine the definition of the attached eddy range of scales, and our DNS suggests that, in this range, the second order structure function depends on filtered skin friction fluctuations in a way which is about the same at different distances from the wall and different local Reynolds numbers.

  6. Investigating Non-Equilibrium Fluctuations of Nanocolloids in a Magnetic Field Using Direct Imaging Methods

    NASA Astrophysics Data System (ADS)

    Rice, Ashley; Oprisan, Ana; Oprisan, Sorinel; Rice-Oprisan College of Charleston Team

    Nanoparticles of iron oxide have a high surface area and can be controlled by an external magnetic field. Since they have a fast response to the applied magnetic field, these systems have been used for numerous in vivo applications, such as MRI contrast enhancement, tissue repair, immunoassay, detoxification of biological fluids, hyperthermia, drug delivery, and cell separation. We performed three direct imaging experiments in order to investigate the concentration-driven fluctuations using magnetic nanoparticles in the absence and in the presence of magnetic field. Our direct imaging experimental setup involved a glass cell filled with magnetic nanocolloidal suspension and water with the concentration gradient oriented against the gravitational field and a superluminescent diode (SLD) as the light source. Nonequilibrium concentration-driven fluctuations were recorded using a direct imaging technique. We used a dynamic structure factor algorithm for image processing in order to compute the structure factor and to find the power law exponents. We saw evidence of large concentration fluctuations and permanent magnetism. Further research will use the correlation time to approximate the diffusion coefficient for the free diffusion experiment. Funded by College of Charleston Department of Undergraduate Research and Creative Activities SURF grant.

  7. Empirical yield tables for Minnesota.

    Treesearch

    Jerold T. Hahn; Gerhard K. Raile

    1982-01-01

    Describes the tables derived from the 1977 Forest Survey of Minnesota and presents examples of how the tables can be used. These tables are broken down according to Minnesota's four Forest Survey Units, 14 forest types, and 5 site index classes. Presents 210 of the 350 possible tables that contained sufficient data to justify publication.

  8. Fluctuation scaling, Taylor's law, and crime.

    PubMed

    Hanley, Quentin S; Khatun, Suniya; Yosef, Amal; Dyer, Rachel-May

    2014-01-01

    Fluctuation scaling relationships have been observed in a wide range of processes ranging from internet router traffic to measles cases. Taylor's law is one such scaling relationship and has been widely applied in ecology to understand communities including trees, birds, human populations, and insects. We show that monthly crime reports in the UK show complex fluctuation scaling which can be approximated by Taylor's law relationships corresponding to local policing neighborhoods and larger regional and countrywide scales. Regression models applied to local scale data from Derbyshire and Nottinghamshire found that different categories of crime exhibited different scaling exponents with no significant difference between the two regions. On this scale, violence reports were close to a Poisson distribution (α = 1.057 ± 0.026) while burglary exhibited a greater exponent (α = 1.292 ± 0.029) indicative of temporal clustering. These two regions exhibited significantly different pre-exponential factors for the categories of anti-social behavior and burglary indicating that local variations in crime reports can be assessed using fluctuation scaling methods. At regional and countrywide scales, all categories exhibited scaling behavior indicative of temporal clustering evidenced by Taylor's law exponents from 1.43 ± 0.12 (Drugs) to 2.094 ± 0081 (Other Crimes). Investigating crime behavior via fluctuation scaling gives insight beyond that of raw numbers and is unique in reporting on all processes contributing to the observed variance and is either robust to or exhibits signs of many types of data manipulation.

  9. Rice piles and sticky deltas: Sediment transport fluctuations in threshold-dominated systems

    NASA Astrophysics Data System (ADS)

    Jerolmack, D. J.

    2008-12-01

    Sediment transport is an intermittent process. Even under perfectly steady boundary conditions, sediment flux in systems as diverse as rivers and rice piles undergoes wild fluctuations as a result of the inherent nonlinear dynamics of transport. This variability confounds geologic interpretation and prediction: "mean" transport rates may be dominated by rare but extreme events such that short-term measurements are not directly comparable to longer-time integrated measurements; autogenic (internally-generated) erosion and depositon events may be mistaken for changes in climate and tectonics where their temporal and spatial scales overlap; and sediment transport may act as a nonlinear filter that obliterates signals of environmental forcing. Sediment transport fluctuations generally result from slow storage and rapid release of sediment within the transport system itself. We hypothesize that the presence of a strong process threshold, and a high degree of internal friction (or "stickiness"), are sufficient conditions to generate intermittent sediment transport behavior. We present experimental data showing similarities in transport fluctuations from three very different systems: gravel bed load transport in a large flume, avalanching in a table-top pile of rice, and shoreline migration in an experimental river delta. Numerical models of a rice pile and an avulsing river delta reproduce these fluctuations, and are used to explore both their origin and also their influence on environmental perturbations. We impose an environmental perturbation on our model systems in the form of cyclically-varying sediment supply. Physical and numerical experiments demonstrate that when the timescale of environmental forcing overlaps with the timescales of autogenic sediment transport fluctuations, the input signal is obliterated and cannot be detected in sediment output from the system. We also demonstrate how variability in transport introduces a dependence of mean transport rate on

  10. Fluctuating Selection in the Moran

    PubMed Central

    Dean, Antony M.; Lehman, Clarence; Yi, Xiao

    2017-01-01

    Contrary to classical population genetics theory, experiments demonstrate that fluctuating selection can protect a haploid polymorphism in the absence of frequency dependent effects on fitness. Using forward simulations with the Moran model, we confirm our analytical results showing that a fluctuating selection regime, with a mean selection coefficient of zero, promotes polymorphism. We find that increases in heterozygosity over neutral expectations are especially pronounced when fluctuations are rapid, mutation is weak, the population size is large, and the variance in selection is big. Lowering the frequency of fluctuations makes selection more directional, and so heterozygosity declines. We also show that fluctuating selection raises dn/ds ratios for polymorphism, not only by sweeping selected alleles into the population, but also by purging the neutral variants of selected alleles as they undergo repeated bottlenecks. Our analysis shows that randomly fluctuating selection increases the rate of evolution by increasing the probability of fixation. The impact is especially noticeable when the selection is strong and mutation is weak. Simulations show the increase in the rate of evolution declines as the rate of new mutations entering the population increases, an effect attributable to clonal interference. Intriguingly, fluctuating selection increases the dn/ds ratios for divergence more than for polymorphism, a pattern commonly seen in comparative genomics. Our model, which extends the classical neutral model of molecular evolution by incorporating random fluctuations in selection, accommodates a wide variety of observations, both neutral and selected, with economy. PMID:28108586

  11. Temporal scaling and spatial statistical analyses of groundwater level fluctuations

    NASA Astrophysics Data System (ADS)

    Sun, H.; Yuan, L., Sr.; Zhang, Y.

    2017-12-01

    Natural dynamics such as groundwater level fluctuations can exhibit multifractionality and/or multifractality due likely to multi-scale aquifer heterogeneity and controlling factors, whose statistics requires efficient quantification methods. This study explores multifractionality and non-Gaussian properties in groundwater dynamics expressed by time series of daily level fluctuation at three wells located in the lower Mississippi valley, after removing the seasonal cycle in the temporal scaling and spatial statistical analysis. First, using the time-scale multifractional analysis, a systematic statistical method is developed to analyze groundwater level fluctuations quantified by the time-scale local Hurst exponent (TS-LHE). Results show that the TS-LHE does not remain constant, implying the fractal-scaling behavior changing with time and location. Hence, we can distinguish the potentially location-dependent scaling feature, which may characterize the hydrology dynamic system. Second, spatial statistical analysis shows that the increment of groundwater level fluctuations exhibits a heavy tailed, non-Gaussian distribution, which can be better quantified by a Lévy stable distribution. Monte Carlo simulations of the fluctuation process also show that the linear fractional stable motion model can well depict the transient dynamics (i.e., fractal non-Gaussian property) of groundwater level, while fractional Brownian motion is inadequate to describe natural processes with anomalous dynamics. Analysis of temporal scaling and spatial statistics therefore may provide useful information and quantification to understand further the nature of complex dynamics in hydrology.

  12. Realtime Hourly Data Table

    Science.gov Websites

    Tables View the latest hourly text summary CLICK ON UNDERLINED HOUR / SHADED BOX FOR THE LATEST CYCLE 00z Dump Tables View the latest rap text summary CLICK ON UNDERLINED HOUR / SHADED BOX FOR THE LATEST CYCLE Data Dump Tables View the latest model data text summary NAM GFS GDS CLICK ON UNDERLINED HOUR / SHADED

  13. Transitions in optimal adaptive strategies for populations in fluctuating environments

    NASA Astrophysics Data System (ADS)

    Mayer, Andreas; Mora, Thierry; Rivoire, Olivier; Walczak, Aleksandra M.

    2017-09-01

    Biological populations are subject to fluctuating environmental conditions. Different adaptive strategies can allow them to cope with these fluctuations: specialization to one particular environmental condition, adoption of a generalist phenotype that compromises between conditions, or population-wise diversification (bet hedging). Which strategy provides the largest selective advantage in the long run depends on the range of accessible phenotypes and the statistics of the environmental fluctuations. Here, we analyze this problem in a simple mathematical model of population growth. First, we review and extend a graphical method to identify the nature of the optimal strategy when the environmental fluctuations are uncorrelated. Temporal correlations in environmental fluctuations open up new strategies that rely on memory but are mathematically challenging to study: We present analytical results to address this challenge. We illustrate our general approach by analyzing optimal adaptive strategies in the presence of trade-offs that constrain the range of accessible phenotypes. Our results extend several previous studies and have applications to a variety of biological phenomena, from antibiotic resistance in bacteria to immune responses in vertebrates.

  14. USEEIO Satellite Tables

    EPA Pesticide Factsheets

    These files contain the environmental data as particular emissions or resources associated with a BEA sectors that are used in the USEEIO model. They are organized by the emission or resources type, as described in the manuscript. The main files (without SI) show the final satellite tables in the 'Exchanges' sheet which have emissions or resource use per USD for 2013. The other sheets in these files provide meta data for the create of the tables, including general information, sources, etc. The 'export' sheet is used for saving the satellite table for csv export. The data dictionary describes the fields in this sheet. The supporting files provide all the details data transformation and organization for the development of the satellite tables.This dataset is associated with the following publication:Yang, Y., W. Ingwersen, T. Hawkins, and D. Meyer. USEEIO: a New and Transparent United States Environmentally Extended Input-Output Model. JOURNAL OF CLEANER PRODUCTION. Elsevier Science Ltd, New York, NY, USA,

  15. Online tables of contents for books: effect on usage*

    PubMed Central

    Morris, Ruth C.

    2001-01-01

    Objectives: To explore whether the presence of online tables of contents (TOC) in an online catalog affects circulation (checkouts and inhouse usage). Two major questions were posed: (1) did the presence of online tables of contents for books increase use, and, (2) if it did, what factors might cause the increase? Method: A randomized and stratified design was used in tracking usage of 3,957 book titles that were previously divided into two groups: one with TOC and one without TOC. Stratification was done for year of imprint, location, subject, previous use, circulating or non-circulating status, and presence of TOC. The use was tracked by the online catalog statistics in the InnoPac online catalog for fourteen months. Results: The study found that tables of contents do increase usage. It also showed a correlation in the size of the effect based on the currency of the titles. In general, even after adjusting for all of the variables (publication date, location, circulation status, subject, and previous use), the odds of a title being used increased by 45% if the titles had online tables of contents, a statistically significant impact at the 0.05 level. Conclusions: This case-control study presents new information about the impact on circulation and inhouse use when tables of contents for books are added to the online catalog record. The study helps to establish the positive role of tables of contents in online catalogs. The research establishes TOC as a major parameter that can be successfully studied using quantitative methods. The study also provides information professionals with some guidance on when enhancement of TOC is likely to be most effective in increasing the use of existing collections. PMID:11209798

  16. Decomposition of spontaneous fluctuations in tumour oxygenation using BOLD MRI and independent component analysis

    PubMed Central

    Gonçalves, Miguel R; Johnson, S Peter; Ramasawmy, Rajiv; Pedley, R Barbara; Lythgoe, Mark F; Walker-Samuel, Simon

    2015-01-01

    Background: Solid tumours can undergo cycles of hypoxia, followed by reoxygenation, which can have significant implications for the success of anticancer therapies. A need therefore exists to develop methods to aid its detection and to further characterise its biological basis. We present here a novel method for decomposing systemic and tumour-specific contributions to fluctuations in tumour deoxyhaemoglobin concentration, based on magnetic resonance imaging measurements. Methods: Fluctuations in deoxyhaemoglobin concentration in two tumour xenograft models of colorectal carcinoma were decomposed into distinct contributions using independent component analysis. These components were then correlated with systemic pulse oximetry measurements to assess the influence of systemic variations in blood oxygenation in tumours, compared with those that arise within the tumour itself (tumour-specific). Immunohistochemical staining was used to assess the physiological basis of each source of fluctuation. Results: Systemic fluctuations in blood oxygenation were found to contribute to cycling hypoxia in tumours, but tumour-specific fluctuations were also evident. Moreover, the size of the tumours was found to influence the degree of systemic, but not tumour-specific, oscillations. The degree of vessel maturation was related to the amplitude of tumour-specific, but not systemic, oscillations. Conclusions: Our results provide further insights into the complexity of spontaneous fluctuations in tumour oxygenation and its relationship with tumour pathophysiology. These observations could be used to develop improved drug delivery strategies. PMID:26484634

  17. Fluctuating Selection in the Moran.

    PubMed

    Dean, Antony M; Lehman, Clarence; Yi, Xiao

    2017-03-01

    Contrary to classical population genetics theory, experiments demonstrate that fluctuating selection can protect a haploid polymorphism in the absence of frequency dependent effects on fitness. Using forward simulations with the Moran model, we confirm our analytical results showing that a fluctuating selection regime, with a mean selection coefficient of zero, promotes polymorphism. We find that increases in heterozygosity over neutral expectations are especially pronounced when fluctuations are rapid, mutation is weak, the population size is large, and the variance in selection is big. Lowering the frequency of fluctuations makes selection more directional, and so heterozygosity declines. We also show that fluctuating selection raises d n / d s ratios for polymorphism, not only by sweeping selected alleles into the population, but also by purging the neutral variants of selected alleles as they undergo repeated bottlenecks. Our analysis shows that randomly fluctuating selection increases the rate of evolution by increasing the probability of fixation. The impact is especially noticeable when the selection is strong and mutation is weak. Simulations show the increase in the rate of evolution declines as the rate of new mutations entering the population increases, an effect attributable to clonal interference. Intriguingly, fluctuating selection increases the d n / d s ratios for divergence more than for polymorphism, a pattern commonly seen in comparative genomics. Our model, which extends the classical neutral model of molecular evolution by incorporating random fluctuations in selection, accommodates a wide variety of observations, both neutral and selected, with economy. Copyright © 2017 by the Genetics Society of America.

  18. Hadronic Correlations and Fluctuations

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

    Koch, Volker

    2008-10-09

    We will provide a review of some of the physics which can be addressed by studying fluctuations and correlations in heavy ion collisions. We will discuss Lattice QCD results on fluctuations and correlations and will put them into context with observables which have been measured in heavy-ion collisions. Special attention will be given to the QCD critical point and the first order co-existence region, and we will discuss how the measurement of fluctuations and correlations can help in an experimental search for non-trivial structures in the QCD phase diagram.

  19. Empirical yield tables for Wisconsin.

    Treesearch

    Jerold T. Hahn; Joan M. Stelman

    1989-01-01

    Describes the tables derived from the 1983 Forest Survey of Wisconsin and presents ways the tables can be used. These tables are broken down according to Wisconsin`s five Forest Survey Units and 14 forest types.

  20. Making a vision document tangible using "vision-tactics-metrics" tables.

    PubMed

    Drury, Ivo; Slomski, Carol

    2006-01-01

    We describe a method of making a vision document tangible by attaching specific tactics and metrics to the key elements of the vision. We report on the development and early use of a "vision-tactics-metrics" table in a department of surgery. Use of the table centered the vision in the daily life of the department and its faculty, and facilitated cultural change.

  1. The Wireless Data Acquisition System for the Vibration Table

    NASA Astrophysics Data System (ADS)

    Teng, Y. T.; Hu, X.

    2014-12-01

    The vibration table is a large-scaled tool used for inspecting the performance of seismometers. The output from a seismometer on the table can be directly monitored when the vibration table moves in certain pattern. Compared with other inspection methods, inspecting seismometers' performance indicators (frequency response, degree of linearity, sensitivity, lateral inhibition and dynamic range etc). using vibration tables is more intuitive. Therefore, the vibration tables are an essential testing part in developing new seismometers and seismometer quality control. Whereas, in practice, a cable is needed to connect the seismometer to the ground equipments for its signal outputs and power supply, that means adding a time-varying nonlinear spring between the vibration table and ground. The cable adds nonlinear feature to the table, distorts the table-board movement and bring extra errors to the inspecting work and affected the testing accuracy and precision. In face of this problem, we developed a wireless acquiring system for the vibration table. The system is consisted of a three-channel analog-to-digital conversion, an acquisition control part, local data storage, network interface, wireless router and power management, etc. The analog-to-digital conversion part uses a 24-digit high-precision converter, which has a programmable amplifier at the front end of its artificial circuit, with the function of matching outputs with different amplifier from the vibration table. The acquisition control part uses a 32 bit ARM processor, with low-power dissipation, minute extension and high performance. The application software platform is written in Linux to make the system convenient for multitasking work. Large volume local digital storage is achieved by a 32G SD card, which is used for saving real time acquired data. Data transmission is achieved by network interface and wireless router, which can simplify the application software by the supported TCP/IP protocol. Besides

  2. Entropic fluctuations in DNA sequences

    NASA Astrophysics Data System (ADS)

    Thanos, Dimitrios; Li, Wentian; Provata, Astero

    2018-03-01

    The Local Shannon Entropy (LSE) in blocks is used as a complexity measure to study the information fluctuations along DNA sequences. The LSE of a DNA block maps the local base arrangement information to a single numerical value. It is shown that despite this reduction of information, LSE allows to extract meaningful information related to the detection of repetitive sequences in whole chromosomes and is useful in finding evolutionary differences between organisms. More specifically, large regions of tandem repeats, such as centromeres, can be detected based on their low LSE fluctuations along the chromosome. Furthermore, an empirical investigation of the appropriate block sizes is provided and the relationship of LSE properties with the structure of the underlying repetitive units is revealed by using both computational and mathematical methods. Sequence similarity between the genomic DNA of closely related species also leads to similar LSE values at the orthologous regions. As an application, the LSE covariance function is used to measure the evolutionary distance between several primate genomes.

  3. Empirical yield tables for Michigan.

    Treesearch

    Jerold T. Hahn; Joan M. Stelman

    1984-01-01

    Describes the tables derived from the 1980 Forest Survey of Michigan and presents ways the tables can be used. These tables are broken down according to Michigan's four Forest Survey Units, 14 forest types, and 5 site-index classes.

  4. Beam Energy Scan of Specific Heat Through Temperature Fluctuations in Heavy Ion Collisions

    NASA Astrophysics Data System (ADS)

    Basu, Sumit; Nandi, Basanta K.; Chatterjee, Sandeep; Chatterjee, Rupa; Nayak, Tapan

    2016-01-01

    Temperature fluctuations may have two distinct origins, first, quantum fluctuations that are initial state fluctuations, and second, thermodynamical fluctuations. We discuss a method of extracting the thermodynamic temperature from the mean transverse momentum of pions, by using controllable parameters such as centrality of the system, and range of the transverse momenta. Event-by-event fluctuations in global temperature over a large phase space provide the specific heat of the system. We present Beam Energy Scan of specific heat from data, AMPT and HRG model prediction. Experimental results from NA49, STAR, PHENIX, PHOBOS and ALICE are combined to obtain the specific heat as a function of beam energy. These results are compared to calculations from AMPT event generator, HRG model and lattice calculations, respectively.

  5. SHAREv2: fluctuations and a comprehensive treatment of decay feed-down

    NASA Astrophysics Data System (ADS)

    Torrieri, G.; Jeon, S.; Letessier, J.; Rafelski, J.

    2006-11-01

    calculations to data it is necessary to consistently take into account resonance decays. However, event-by-event fluctuations are more sensitive than particle yields to experimental acceptance issues, and a range of techniques needs to be implemented to extract 'physical' fluctuations from an experimental event-by-event measurement. Method of solving the problem:The techniques used within the SHARE suite of programs [G. Torrieri, S. Steinke, W. Broniowski, W. Florkowski, J. Letessier, J. Rafelski, Comput. Phys. Comm. 167 (2005) 229; SHAREv1] are updated and extended to fluctuations. A full particle data-table, decay tree, and set of experimental feed-down coefficients are provided. Unlike SHAREv1.x, experimental acceptance feed-down coefficients can be entered for any resonance decay. SHAREv2 can calculate yields, fluctuations, and bulk properties of the fireball from provided thermal parameters; alternatively, parameters can be obtained from fits to experimental data, via the MINUIT fitting algorithm [F. James, M. Roos, Comput. Phys. Comm. 10 (1975) 343]. Fits can also be analyzed for significance, parameter and data point sensitivity. Averages and fluctuations at freeze-out of both the stable particles and the hadronic resonances are set according to a statistical prescription, calculated via a series of Bessel functions, using CERN library programs. We also have the option of including finite particle widths of the resonances. A χ minimization algorithm, also from the CERN library programs, is used to perform and analyze the fit. Please see SHAREv1 for more details on these. Purpose:The vast amount of high quality soft hadron production data, from experiments running at the SPS, RHIC, in past at the AGS, and in the near future at the LHC, offers the opportunity for statistical particle production model falsification. This task has turned out to be difficult when considering solely particle yields addressed in the context of SHAREv1.x. For this reason physical conditions at

  6. Fully Quantum Fluctuation Theorems

    NASA Astrophysics Data System (ADS)

    Åberg, Johan

    2018-02-01

    Systems that are driven out of thermal equilibrium typically dissipate random quantities of energy on microscopic scales. Crooks fluctuation theorem relates the distribution of these random work costs to the corresponding distribution for the reverse process. By an analysis that explicitly incorporates the energy reservoir that donates the energy and the control system that implements the dynamic, we obtain a quantum generalization of Crooks theorem that not only includes the energy changes in the reservoir but also the full description of its evolution, including coherences. Moreover, this approach opens up the possibility for generalizations of the concept of fluctuation relations. Here, we introduce "conditional" fluctuation relations that are applicable to nonequilibrium systems, as well as approximate fluctuation relations that allow for the analysis of autonomous evolution generated by global time-independent Hamiltonians. We furthermore extend these notions to Markovian master equations, implicitly modeling the influence of the heat bath.

  7. A New Approach to Simulate Groundwater Table Dynamics and Its Validation in China

    NASA Astrophysics Data System (ADS)

    Lv, M.; Lu, H.; Dan, L.; Yang, K.

    2017-12-01

    The groundwater has very important role in hydrology-climate-human activity interaction. But the groundwater table dynamics currently is not well simulated in global-scale land surface models. Meanwhile, almost all groundwater schemes are adopting a specific yield method to estimate groundwater table, in which how to determine the proper specific yield value remains a big challenge. In this study, we developed a Soil Moisture Correlation (SMC) method to simulate groundwater table dynamics. We coupled SMC with a hydrological model (named as NEW) and compared it with the original model in which a specific yield method is used (named as CTL). Both NEW and CTL were tested in Tangnaihai Subbasin of Yellow River and Jialingjiang Subbasin along Yangtze River, where underground water is less impacted by human activities. The simulated discharges by NEW and CTL are compared against gauge observations. The comparison results reveal that after calibration both models are able to reproduce the discharge well. However, there is no parameter needed to be calibrated for SMC. It indicates that SMC method is more efficient and easy-to-use than the specific yield method. Since there is no direct groundwater table observation in these two basins, simulated groundwater table were compared with a global data set provided by Fan et al. (2013). Both NEW and CTL estimate lower depths than Fan does. Moreover, when comparing the variation of terrestrial water storage (TWS) derived from NEW with that observed by GRACE, good agreements were confirmed. It demonstrated that SMC method is able to reproduce groundwater level dynamics reliably.

  8. Fluctuations of the gluon distribution from the small- x effective action

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

    Dumitru, Adrian; Skokov, Vladimir

    The computation of observables in high-energy QCD involves an average over stochastic semiclassical small-x gluon fields. The weight of various configurations is determined by the effective action. We introduce a method to study fluctuations of observables, functionals of the small-x fields, which does not explicitly involve dipoles. We integrate out those fluctuations of the semiclassical gluon field under which a given observable is invariant. Thereby we obtain the effective potential for that observable describing its fluctuations about the average. Here, we determine explicitly the effective potential for the covariant gauge gluon distribution both for the McLerran-Venugopalan (MV) model and formore » a (nonlocal) Gaussian approximation for the small-x effective action. This provides insight into the correlation of fluctuations of the number of hard gluons versus their typical transverse momentum. We find that the spectral shape of the fluctuations of the gluon distribution is fundamentally different in the MV model, where there is a pileup of gluons near the saturation scale, versus the solution of the small-x JIMWLK renormalization group, which generates essentially scale-invariant fluctuations above the absorptive boundary set by the saturation scale.« less

  9. Fluctuations of the gluon distribution from the small- x effective action

    DOE PAGES

    Dumitru, Adrian; Skokov, Vladimir

    2017-09-29

    The computation of observables in high-energy QCD involves an average over stochastic semiclassical small-x gluon fields. The weight of various configurations is determined by the effective action. We introduce a method to study fluctuations of observables, functionals of the small-x fields, which does not explicitly involve dipoles. We integrate out those fluctuations of the semiclassical gluon field under which a given observable is invariant. Thereby we obtain the effective potential for that observable describing its fluctuations about the average. Here, we determine explicitly the effective potential for the covariant gauge gluon distribution both for the McLerran-Venugopalan (MV) model and formore » a (nonlocal) Gaussian approximation for the small-x effective action. This provides insight into the correlation of fluctuations of the number of hard gluons versus their typical transverse momentum. We find that the spectral shape of the fluctuations of the gluon distribution is fundamentally different in the MV model, where there is a pileup of gluons near the saturation scale, versus the solution of the small-x JIMWLK renormalization group, which generates essentially scale-invariant fluctuations above the absorptive boundary set by the saturation scale.« less

  10. Dynamics of Viral Abundance and Diversity in a Sphagnum-Dominated Peatland: Temporal Fluctuations Prevail Over Habitat.

    PubMed

    Ballaud, Flore; Dufresne, Alexis; Francez, André-Jean; Colombet, Jonathan; Sime-Ngando, Télesphore; Quaiser, Achim

    2015-01-01

    Viruses impact microbial activity and carbon cycling in various environments, but their diversity and ecological importance in Sphagnum-peatlands are unknown. Abundances of viral particles and prokaryotes were monitored bi-monthly at a fen and a bog at two different layers of the peat surface. Viral particle abundance ranged from 1.7 x 10(6) to 5.6 x 10(8) particles mL(-1), and did not differ between fen and bog but showed seasonal fluctuations. These fluctuations were positively correlated with prokaryote abundance and dissolved organic carbon, and negatively correlated with water-table height and dissolved oxygen. Using shotgun metagenomics we observed a shift in viral diversity between winter/spring and summer/autumn, indicating a seasonal succession of viral communities, mainly driven by weather-related environmental changes. Based on the seasonal asynchrony between viral and microbial diversity, we hypothesize a seasonal shift in the active microbial communities associated with a shift from lysogenic to lytic lifestyles. Our results suggest that temporal variations of environmental conditions rather than current habitat differences control the dynamics of virus-host interactions in Sphagnum-dominated peatlands.

  11. Default "Gunel and Dickey" Bayes factors for contingency tables.

    PubMed

    Jamil, Tahira; Ly, Alexander; Morey, Richard D; Love, Jonathon; Marsman, Maarten; Wagenmakers, Eric-Jan

    2017-04-01

    The analysis of R×C contingency tables usually features a test for independence between row and column counts. Throughout the social sciences, the adequacy of the independence hypothesis is generally evaluated by the outcome of a classical p-value null-hypothesis significance test. Unfortunately, however, the classical p-value comes with a number of well-documented drawbacks. Here we outline an alternative, Bayes factor method to quantify the evidence for and against the hypothesis of independence in R×C contingency tables. First we describe different sampling models for contingency tables and provide the corresponding default Bayes factors as originally developed by Gunel and Dickey (Biometrika, 61(3):545-557 (1974)). We then illustrate the properties and advantages of a Bayes factor analysis of contingency tables through simulations and practical examples. Computer code is available online and has been incorporated in the "BayesFactor" R package and the JASP program ( jasp-stats.org ).

  12. Multiple Lookup Table-Based AES Encryption Algorithm Implementation

    NASA Astrophysics Data System (ADS)

    Gong, Jin; Liu, Wenyi; Zhang, Huixin

    Anew AES (Advanced Encryption Standard) encryption algorithm implementation was proposed in this paper. It is based on five lookup tables, which are generated from S-box(the substitution table in AES). The obvious advantages are reducing the code-size, improving the implementation efficiency, and helping new learners to understand the AES encryption algorithm and GF(28) multiplication which are necessary to correctly implement AES[1]. This method can be applied on processors with word length 32 or above, FPGA and others. And correspondingly we can implement it by VHDL, Verilog, VB and other languages.

  13. Solar cell efficiency tables (version 48): Solar cell efficiency tables (version 48)

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

    Green, Martin A.; Emery, Keith; Hishikawa, Yoshihiro

    Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since January 2016 are reviewed.

  14. Theory of slightly fluctuating ratchets

    NASA Astrophysics Data System (ADS)

    Rozenbaum, V. M.; Shapochkina, I. V.; Lin, S. H.; Trakhtenberg, L. I.

    2017-04-01

    We consider a Brownian particle moving in a slightly fluctuating potential. Using the perturbation theory on small potential fluctuations, we derive a general analytical expression for the average particle velocity valid for both flashing and rocking ratchets with arbitrary, stochastic or deterministic, time dependence of potential energy fluctuations. The result is determined by the Green's function for diffusion in the time-independent part of the potential and by the features of correlations in the fluctuating part of the potential. The generality of the result allows describing complex ratchet systems with competing characteristic times; these systems are exemplified by the model of a Brownian photomotor with relaxation processes of finite duration.

  15. Characteristics of Tables for Disseminating Biobehavioral Results.

    PubMed

    Schneider, Barbara St Pierre; Nagelhout, Ed; Feng, Du

    2018-01-01

    To report the complexity and richness of study variables within biological nursing research, authors often use tables; however, the ease with which consumers understand, synthesize, evaluate, and build upon findings depends partly upon table design. To assess and compare table characteristics within research and review articles published in Biological Research for Nursing and Nursing Research. A total of 10 elements in tables from 48 biobehavioral or biological research or review articles were analyzed. To test six hypotheses, a two-level hierarchical linear model was used for each of the continuous table elements, and a two-level hierarchical generalized linear model was used for each of the categorical table elements. Additionally, the inclusion of probability values in statistical tables was examined. The mean number of tables per article was 3. Tables in research articles were more likely to contain quantitative content, while tables in review articles were more likely to contain both quantitative and qualitative content. Tables in research articles had a greater number of rows, columns, and column-heading levels than tables in review articles. More than one half of statistical tables in research articles had a separate probability column or had probability values within the table, whereas approximately one fourth had probability notes. Authors and journal editorial staff may be generating tables that better depict biobehavioral content than those identified in specific style guidelines. However, authors and journal editorial staff may want to consider table design in terms of audience, including alternative visual displays.

  16. Effect of ripples on the finite temperature elastic properties of hexagonal boron nitride using strain-fluctuation method

    NASA Astrophysics Data System (ADS)

    Thomas, Siby; Ajith, K. M.; Valsakumar, M. C.

    2017-11-01

    This work intents to put forth the results of a classical molecular dynamics study to investigate the temperature dependent elastic constants of monolayer hexagonal boron nitride (h-BN) between 100 and 1000 K for the first time using strain fluctuation method. The temperature dependence of out-of-plane fluctuations (ripples) is quantified and is explained using continuum theory of membranes. At low temperatures, negative in-plane thermal expansion is observed and at high temperatures, a transition to positive thermal expansion has been observed due to the presence of thermally excited ripples. The decrease of Young's modulus, bulk modulus, shear modulus and Poisson's ratio with increase in temperature has been analyzed. The thermal rippling in h-BN leads to strong anharmonic behaviour that causes large deviation from the isotropic elasticity. A detailed study shows that the strong thermal rippling in large systems is also responsible for the softening of elastic constants in h-BN. From the determined values of elastic constants and elastic moduli, it has been elucidated that 2D h-BN sheets meet the Born's mechanical stability criterion in the investigated temperature range. The variation of longitudinal and shear velocities with temperature is also calculated from the computed values of elastic constants and elastic moduli.

  17. Differential interferometry for measurement of density fluctuations and fluctuation-induced transport (invited)

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

    Lin, L.; Ding, W. X.; Brower, D. L.

    2010-10-15

    Differential interferometry employs two parallel laser beams with a small spatial offset (less than beam width) and frequency difference (1-2 MHz) using common optics and a single mixer for a heterodyne detection. The differential approach allows measurement of the electron density gradient, its fluctuations, as well as the equilibrium density distribution. This novel interferometry technique is immune to fringe skip errors and is particularly useful in harsh plasma environments. Accurate calibration of the beam spatial offset, accomplished by use of a rotating dielectric wedge, is required to enable broad application of this approach. Differential interferometry has been successfully used onmore » the Madison Symmetric Torus reversed-field pinch plasma to directly measure fluctuation-induced transport along with equilibrium density profile evolution during pellet injection. In addition, by combining differential and conventional interferometry, both linear and nonlinear terms of the electron density fluctuation energy equation can be determined, thereby allowing quantitative investigation of the origin of the density fluctuations. The concept, calibration, and application of differential interferometry are presented.« less

  18. The Spectrum of Wind Power Fluctuations

    NASA Astrophysics Data System (ADS)

    Bandi, Mahesh

    2016-11-01

    Wind is a variable energy source whose fluctuations threaten electrical grid stability and complicate dynamical load balancing. The power generated by a wind turbine fluctuates due to the variable wind speed that blows past the turbine. Indeed, the spectrum of wind power fluctuations is widely believed to reflect the Kolmogorov spectrum; both vary with frequency f as f - 5 / 3. This variability decreases when aggregate power fluctuations from geographically distributed wind farms are averaged at the grid via a mechanism known as geographic smoothing. Neither the f - 5 / 3 wind power fluctuation spectrum nor the mechanism of geographic smoothing are understood. In this work, we explain the wind power fluctuation spectrum from the turbine through grid scales. The f - 5 / 3 wind power fluctuation spectrum results from the largest length scales of atmospheric turbulence of order 200 km influencing the small scales where individual turbines operate. This long-range influence spatially couples geographically distributed wind farms and synchronizes farm outputs over a range of frequencies and decreases with increasing inter-farm distance. Consequently, aggregate grid-scale power fluctuations remain correlated, and are smoothed until they reach a limiting f - 7 / 3 spectrum. This work was funded by the Collective Interactions Unit, OIST Graduate University, Japan.

  19. Interpolations of groundwater table elevation in dissected uplands.

    PubMed

    Chung, Jae-won; Rogers, J David

    2012-01-01

    The variable elevation of the groundwater table in the St. Louis area was estimated using multiple linear regression (MLR), ordinary kriging, and cokriging as part of a regional program seeking to assess liquefaction potential. Surface water features were used to determine the minimum water table for MLR and supplement the principal variables for ordinary kriging and cokriging. By evaluating the known depth to the water and the minimum water table elevation, the MLR analysis approximates the groundwater elevation for a contiguous hydrologic system. Ordinary kriging and cokriging estimate values in unsampled areas by calculating the spatial relationships between the unsampled and sampled locations. In this study, ordinary kriging did not incorporate topographic variations as an independent variable, while cokriging included topography as a supporting covariable. Cross validation suggests that cokriging provides a more reliable estimate at known data points with less uncertainty than the other methods. Profiles extending through the dissected uplands terrain suggest that: (1) the groundwater table generated by MLR mimics the ground surface and elicits a exaggerated interpolation of groundwater elevation; (2) the groundwater table estimated by ordinary kriging tends to ignore local topography and exhibits oversmoothing of the actual undulations in the water table; and (3) cokriging appears to give the realistic water surface, which rises and falls in proportion to the overlying topography. The authors concluded that cokriging provided the most realistic estimate of the groundwater surface, which is the key variable in assessing soil liquefaction potential in unconsolidated sediments. © 2011, The Author(s). Ground Water © 2011, National Ground Water Association.

  20. Ion temperature fluctuation measurements using a retarding field analyzer

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

    Nedzelskiy, I. S.; Silva, C.; Duarte, P.

    2011-04-15

    The retarding field analyzer (RFA) is a widely used diagnostic tool for the ion temperature measurement in the scrape-off-layer (SOL) of the thermonuclear plasma devices. However, the temporal resolution in the standard RFA application is restricted to the ms timescale. In this paper, a dc operation of the RFA is considered, which allows for the measurement of the plasma ion temperature fluctuations. The method is based on the relation for the RFA current-voltage (I-V) characteristic resulted from a common RFA model of shifted Maxwellian distribution of the analyzed ions, and the measurements of two points on the exponentially decaying regionmore » of the I-V characteristic with two differently dc biased RFA electrodes. The method has been tested and compared with conventional RFA measurements of the ion temperature in the tokamak ISTTOK SOL plasma. An ion temperature of T{sub i}= 17 eV is obtained near the limiter position. The agreement between the results of the two methods is within {approx}25%. The amplitude of the ion temperature fluctuations is found to be around 5 eV at this location. The method has been validated by taking into account the effect of fluctuations in the plasma potential and the noise contamination, proving the reliability of the results obtained. Finally, constrains to the method application are discussed that include a negligible electron emission from the RFA grids and the restriction to operate in the exponentially decaying region of the I-V characteristic.« less

  1. Analysis of swarm behaviors based on an inversion of the fluctuation theorem.

    PubMed

    Hamann, Heiko; Schmickl, Thomas; Crailsheim, Karl

    2014-01-01

    A grand challenge in the field of artificial life is to find a general theory of emergent self-organizing systems. In swarm systems most of the observed complexity is based on motion of simple entities. Similarly, statistical mechanics focuses on collective properties induced by the motion of many interacting particles. In this article we apply methods from statistical mechanics to swarm systems. We try to explain the emergent behavior of a simulated swarm by applying methods based on the fluctuation theorem. Empirical results indicate that swarms are able to produce negative entropy within an isolated subsystem due to frozen accidents. Individuals of a swarm are able to locally detect fluctuations of the global entropy measure and store them, if they are negative entropy productions. By accumulating these stored fluctuations over time the swarm as a whole is producing negative entropy and the system ends up in an ordered state. We claim that this indicates the existence of an inverted fluctuation theorem for emergent self-organizing dissipative systems. This approach bears the potential of general applicability.

  2. Coordinated Control of Wind Turbine and Energy Storage System for Reducing Wind Power Fluctuation

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

    Kim, Chunghun; Muljadi, Eduard; Chung, Chung Choo

    This paper proposes a method for the coordinated control of a wind turbine and an energy storage system (ESS). Because wind power (WP) is highly dependent on wind speed, which is variable, severe stability problems can be caused in power systems, especially when the WP has a high penetration level. To solve this problem, many power generation corporations or grid operators have begun using ESSs. An ESS has very quick response and good performance for reducing the impact of WP fluctuation; however, its installation cost is high. Therefore, it is important to design the control algorithm by considering both themore » ESS capacity and WP fluctuation. Thus, we propose a control algorithm to mitigate the WP fluctuation by using the coordinated control between the wind turbine and the ESS by considering the ESS capacity and the WP fluctuation. Using de-loaded control, according to the WP fluctuation and ESS capacity, we can expand the ESS lifespan and improve grid reliability by avoiding the extreme value of state of charge (SoC) (i.e., 0 or 1 pu). The effectiveness of the proposed method was validated via MATLAB/Simulink by considering a small power system that includes both a wind turbine generator and conventional generators that react to system frequency deviation. We found that the proposed method has better performance in SoC management, thereby improving the frequency regulation by mitigating the impact of the WP fluctuation on the small power system.« less

  3. Coordinated Control of Wind Turbine and Energy Storage System for Reducing Wind Power Fluctuation

    DOE PAGES

    Kim, Chunghun; Muljadi, Eduard; Chung, Chung Choo

    2017-12-27

    This paper proposes a method for the coordinated control of a wind turbine and an energy storage system (ESS). Because wind power (WP) is highly dependent on wind speed, which is variable, severe stability problems can be caused in power systems, especially when the WP has a high penetration level. To solve this problem, many power generation corporations or grid operators have begun using ESSs. An ESS has very quick response and good performance for reducing the impact of WP fluctuation; however, its installation cost is high. Therefore, it is important to design the control algorithm by considering both themore » ESS capacity and WP fluctuation. Thus, we propose a control algorithm to mitigate the WP fluctuation by using the coordinated control between the wind turbine and the ESS by considering the ESS capacity and the WP fluctuation. Using de-loaded control, according to the WP fluctuation and ESS capacity, we can expand the ESS lifespan and improve grid reliability by avoiding the extreme value of state of charge (SoC) (i.e., 0 or 1 pu). The effectiveness of the proposed method was validated via MATLAB/Simulink by considering a small power system that includes both a wind turbine generator and conventional generators that react to system frequency deviation. We found that the proposed method has better performance in SoC management, thereby improving the frequency regulation by mitigating the impact of the WP fluctuation on the small power system.« less

  4. The transmission of fluctuation among price indices based on Granger causality network

    NASA Astrophysics Data System (ADS)

    Sun, Qingru; Gao, Xiangyun; Wen, Shaobo; Chen, Zhihua; Hao, Xiaoqing

    2018-09-01

    In this paper, we provide a method of statistical physics to analyze the fluctuation of transmission by constructing Granger causality network among price indices (PIGCN) from a systematical perspective, using complex network theory combined with Granger causality method. In economic system, there are numerous price indices, of which the relationships are extreme complicated. Thus, time series data of 6 types of price indices of China, including 113 kinds of sub price indices, are selected as example of empirical study. Through the analysis of the structure of PIGCN, we identify important price indices with high transmission range, high intermediation capacity, high cohesion and the fluctuation transmission path of price indices, respectively. Furthermore, dynamic relationships among price indices are revealed. Based on these results, we provide several policy implications for monitoring the diffusion of risk of price fluctuation. Our method can also be used to study the price indices of other countries, which is generally applicable.

  5. The hidden sister of motor fluctuations in Parkinson's disease: A review on nonmotor fluctuations.

    PubMed

    Martínez-Fernández, Raul; Schmitt, Emmanuelle; Martinez-Martin, Pablo; Krack, Paul

    2016-08-01

    Only a few years after the introduction of levodopa, the first descriptions of motor fluctuations and dyskinesia related to dopaminergic therapy appeared. In PD, attention turned to their management, that had dampened the euphoria of the "levodopa miracle." It soon became clear that neuropsychiatric, autonomic, and sensory features also tend to develop fluctuations after chronic exposure to l-dopa. The diversity of fluctuating nonmotor symptoms, their largely subjective nature, coupled with a frequent lack of insight led to difficulties in identification and quantification. This may explain why, despite the high impact of nonmotor symptoms on patient autonomy and quality of life, evaluation of nonmotor fluctuations is not part of clinical routine. In view of the lack of specific validated assessment tools, detailed anamnesis should ideally be coupled with an evaluation in both ON and OFF drug conditions. The mechanisms of nonmotor fluctuations are not well understood. It is thought that they share dopaminergic presynaptic pharmacokinetic and postsynaptic pharmacodynamic mechanisms with the classical motor complications, but involve different neural pathways. Although symptoms fluctuate with dopaminergic treatment, serotonine and norepinephrine denervation, as well as interactions between neurotransmitter systems, probably contribute to their diversity. The lack of validated tools for assessment of these phenomena explains the almost complete absence of treatment studies. Management, largely resulting from expert opinion, includes psychiatric follow-up, nondopaminergic drugs, and advanced dopaminergic treatment, including drug delivery pumps and DBS. This review aims to provide a starting point for the understanding, diagnosis, and management of nonmotor fluctuations. © 2016 International Parkinson and Movement Disorder Society. © 2016 International Parkinson and Movement Disorder Society.

  6. Principle of minimal work fluctuations.

    PubMed

    Xiao, Gaoyang; Gong, Jiangbin

    2015-08-01

    Understanding and manipulating work fluctuations in microscale and nanoscale systems are of both fundamental and practical interest. For example, in considering the Jarzynski equality 〈e-βW〉=e-βΔF, a change in the fluctuations of e-βW may impact how rapidly the statistical average of e-βW converges towards the theoretical value e-βΔF, where W is the work, β is the inverse temperature, and ΔF is the free energy difference between two equilibrium states. Motivated by our previous study aiming at the suppression of work fluctuations, here we obtain a principle of minimal work fluctuations. In brief, adiabatic processes as treated in quantum and classical adiabatic theorems yield the minimal fluctuations in e-βW. In the quantum domain, if a system initially prepared at thermal equilibrium is subjected to a work protocol but isolated from a bath during the time evolution, then a quantum adiabatic process without energy level crossing (or an assisted adiabatic process reaching the same final states as in a conventional adiabatic process) yields the minimal fluctuations in e-βW, where W is the quantum work defined by two energy measurements at the beginning and at the end of the process. In the classical domain where the classical work protocol is realizable by an adiabatic process, then the classical adiabatic process also yields the minimal fluctuations in e-βW. Numerical experiments based on a Landau-Zener process confirm our theory in the quantum domain, and our theory in the classical domain explains our previous numerical findings regarding the suppression of classical work fluctuations [G. Y. Xiao and J. B. Gong, Phys. Rev. E 90, 052132 (2014)].

  7. Regional Input-Output Tables and Trade Flows: an Integrated and Interregional Non-survey Approach

    DOE PAGES

    Boero, Riccardo; Edwards, Brian Keith; Rivera, Michael Kelly

    2017-03-20

    Regional input–output tables and trade flows: an integrated and interregional non-survey approach. Regional Studies. Regional analyses require detailed and accurate information about dynamics happening within and between regional economies. However, regional input–output tables and trade flows are rarely observed and they must be estimated using up-to-date information. Common estimation approaches vary widely but consider tables and flows independently. Here, by using commonly used economic assumptions and available economic information, this paper presents a method that integrates the estimation of regional input–output tables and trade flows across regions. Examples of the method implementation are presented and compared with other approaches, suggestingmore » that the integrated approach provides advantages in terms of estimation accuracy and analytical capabilities.« less

  8. Regional Input-Output Tables and Trade Flows: an Integrated and Interregional Non-survey Approach

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

    Boero, Riccardo; Edwards, Brian Keith; Rivera, Michael Kelly

    Regional input–output tables and trade flows: an integrated and interregional non-survey approach. Regional Studies. Regional analyses require detailed and accurate information about dynamics happening within and between regional economies. However, regional input–output tables and trade flows are rarely observed and they must be estimated using up-to-date information. Common estimation approaches vary widely but consider tables and flows independently. Here, by using commonly used economic assumptions and available economic information, this paper presents a method that integrates the estimation of regional input–output tables and trade flows across regions. Examples of the method implementation are presented and compared with other approaches, suggestingmore » that the integrated approach provides advantages in terms of estimation accuracy and analytical capabilities.« less

  9. Centrifugal compressor surge detecting method based on wavelet analysis of unsteady pressure fluctuations in typical stages

    NASA Astrophysics Data System (ADS)

    Izmaylov, R.; Lebedev, A.

    2015-08-01

    Centrifugal compressors are complex energy equipment. Automotive control and protection system should meet the requirements: of operation reliability and durability. In turbocompressors there are at least two dangerous areas: surge and rotating stall. Antisurge protecting systems usually use parametric or feature methods. As a rule industrial system are parametric. The main disadvantages of anti-surge parametric systems are difficulties in mass flow measurements in natural gas pipeline compressor. The principal idea of feature method is based on the experimental fact: as a rule just before the onset of surge rotating or precursor stall established in compressor. In this case the problem consists in detecting of unsteady pressure or velocity fluctuations characteristic signals. Wavelet analysis is the best method for detecting onset of rotating stall in spite of high level of spurious signals (rotating wakes, turbulence, etc.). This method is compatible with state of the art DSP systems of industrial control. Examples of wavelet analysis application for detecting onset of rotating stall in typical stages centrifugal compressor are presented. Experimental investigations include unsteady pressure measurement and sophisticated data acquisition system. Wavelet transforms used biorthogonal wavelets in Mathlab systems.

  10. Electronic Noise and Fluctuations in Solids

    NASA Astrophysics Data System (ADS)

    Kogan, Sh.

    2008-07-01

    Preface; Part I. Introduction. Some Basic Concepts of the Theory of Random Processes: 1. Probability density functions. Moments. Stationary processes; 2. Correlation function; 3. Spectral density of noise; 4. Ergodicity and nonergodicity of random processes; 5. Random pulses and shot noise; 6. Markov processes. General theory; 7. Discrete Markov processes. Random telegraph noise; 8. Quasicontinuous (Diffusion-like) Markov processes; 9. Brownian motion; 10. Langevin approach to the kinetics of fluctuations; Part II. Fluctuation-Dissipation Relations in Equilibrium Systems: 11. Derivation of fluctuation-dissipation relations; 12. Equilibrium noise in quasistationary circuits. Nyquist theorem; 13. Fluctuations of electromagnetic fields in continuous media; Part III. Fluctuations in Nonequilibrium Gases: 14. Some basic concepts of hot-electrons' physics; 15. Simple model of current fluctuations in a semiconductor with hot electrons; 16. General kinetic theory of quasiclassical fluctuations in a gas of particles. The Boltzmann-Langevin equation; 17. Current fluctuations and noise temperature; 18. Current fluctuations and diffusion in a gas of hot electrons; 19. One-time correlation in nonequilibrium gases; 20. Intervalley noise in multivalley semiconductors; 21. Noise of hot electrons emitting optical phonons in the streaming regime; 22. Noise in a semiconductor with a postbreakdown stable current filament; Part IV. Generation-recombination noise: 23. G-R noise in uniform unipolar semiconductors; 24. Noise produced by recombination and diffusion; Part V. Noise in quantum ballistic systems: 25. Introduction; 26. Equilibrium noise and shot noise in quantum conductors; 27. Modulation noise in quantum point contacts; 28. Transition from a ballistic conductor to a macroscopic one; 29. Noise in tunnel junctions; Part VI. Resistance noise in metals: 30. Incoherent scattering of electrons by mobile defects; 31. Effect of mobile scattering centers on the electron interference

  11. Advances in food composition tables in Japan-Standard Tables Of Food Composition in Japan - 2015 - (Seventh Revised Edition).

    PubMed

    Watanabe, Tomoko; Kawai, Ryoko

    2018-01-01

    The latest version of the Standard Tables of Food Composition in Japan-2015- comprises the main food composition table (Standard Tables of Food Composition in Japan-2015-[Seventh revised Edition)) and three supplementary books. The supplementary books are Standard Tables of Food Composition in Japan - 2015 - (Seventh Revised Edition) - Amino Acids -, Standard Tables of Food Composition in Japan - 2015 - (Seventh Revised Edition) - Fatty Acids - and Standard Tables of Food Composition in Japan - 2015 - (Seventh Revised Edition) - Available Carbohydrates, Polyols and Organic Acids-. We believe understanding these food composition tables can give greater insight into Japan's gastronomic culture and changes in eating habits. We expect them to play important roles as part of the East Asia food composition tables. Copyright © 2017. Published by Elsevier Ltd.

  12. Fluctuation-driven price dynamics and investment strategies

    PubMed Central

    Li, Yan; Zheng, Bo; Chen, Ting-Ting; Jiang, Xiong-Fei

    2017-01-01

    Investigation of the driven mechanism of the price dynamics in complex financial systems is important and challenging. In this paper, we propose an investment strategy to study how dynamic fluctuations drive the price movements. The strategy is successfully applied to different stock markets in the world, and the result indicates that the driving effect of the dynamic fluctuations is rather robust. We investigate how the strategy performance is influenced by the market states and optimize the strategy performance by introducing two parameters. The strategy is also compared with several typical technical trading rules. Our findings not only provide an investment strategy which extends investors’ profits, but also offer a useful method to look into the dynamic properties of complex financial systems. PMID:29240783

  13. Fluctuation-driven price dynamics and investment strategies.

    PubMed

    Li, Yan; Zheng, Bo; Chen, Ting-Ting; Jiang, Xiong-Fei

    2017-01-01

    Investigation of the driven mechanism of the price dynamics in complex financial systems is important and challenging. In this paper, we propose an investment strategy to study how dynamic fluctuations drive the price movements. The strategy is successfully applied to different stock markets in the world, and the result indicates that the driving effect of the dynamic fluctuations is rather robust. We investigate how the strategy performance is influenced by the market states and optimize the strategy performance by introducing two parameters. The strategy is also compared with several typical technical trading rules. Our findings not only provide an investment strategy which extends investors' profits, but also offer a useful method to look into the dynamic properties of complex financial systems.

  14. Heat fluctuations of Brownian oscillators in nonstationary processes: Fluctuation theorem and condensation transition

    NASA Astrophysics Data System (ADS)

    Crisanti, A.; Sarracino, A.; Zannetti, M.

    2017-05-01

    We study analytically the probability distribution of the heat released by an ensemble of harmonic oscillators to the thermal bath, in the nonequilibrium relaxation process following a temperature quench. We focus on the asymmetry properties of the heat distribution in the nonstationary dynamics, in order to study the forms taken by the fluctuation theorem as the number of degrees of freedom is varied. After analyzing in great detail the cases of one and two oscillators, we consider the limit of a large number of oscillators, where the behavior of fluctuations is enriched by a condensation transition with a nontrivial phase diagram, characterized by reentrant behavior. Numerical simulations confirm our analytical findings. We also discuss and highlight how concepts borrowed from the study of fluctuations in equilibrium under symmetry-breaking conditions [Gaspard, J. Stat. Mech. (2012) P08021, 10.1088/1742-5468/2012/08/P08021] turn out to be quite useful in understanding the deviations from the standard fluctuation theorem.

  15. Resonant tunneling of fluctuation Cooper pairs

    PubMed Central

    Galda, Alexey; Mel'nikov, A. S.; Vinokur, V. M.

    2015-01-01

    Superconducting fluctuations have proved to be an irreplaceable source of information about microscopic and macroscopic material parameters that could be inferred from the experiment. According to common wisdom, the effect of thermodynamic fluctuations in the vicinity of the superconducting transition temperature, Tc, is to round off all of the sharp corners and discontinuities, which otherwise would have been expected to occur at Tc. Here we report the current spikes due to radiation-induced resonant tunneling of fluctuation Cooper pairs between two superconductors which grow even sharper and more pronounced upon approach to Tc. This striking effect offers an unprecedented tool for direct measurements of fluctuation Cooper pair lifetime, which is key to our understanding of the fluctuation regime, most notably to nature of the pseudogap state in high-temperature superconductors. Our finding marks a radical departure from the conventional view of superconducting fluctuations as a blurring and rounding phenomenon. PMID:25661237

  16. Resonant tunneling of fluctuation Cooper pairs.

    PubMed

    Galda, Alexey; Mel'nikov, A S; Vinokur, V M

    2015-02-09

    Superconducting fluctuations have proved to be an irreplaceable source of information about microscopic and macroscopic material parameters that could be inferred from the experiment. According to common wisdom, the effect of thermodynamic fluctuations in the vicinity of the superconducting transition temperature, Tc, is to round off all of the sharp corners and discontinuities, which otherwise would have been expected to occur at Tc. Here we report the current spikes due to radiation-induced resonant tunneling of fluctuation Cooper pairs between two superconductors which grow even sharper and more pronounced upon approach to Tc. This striking effect offers an unprecedented tool for direct measurements of fluctuation Cooper pair lifetime, which is key to our understanding of the fluctuation regime, most notably to nature of the pseudogap state in high-temperature superconductors. Our finding marks a radical departure from the conventional view of superconducting fluctuations as a blurring and rounding phenomenon.

  17. Continuous information flow fluctuations

    NASA Astrophysics Data System (ADS)

    Rosinberg, Martin Luc; Horowitz, Jordan M.

    2016-10-01

    Information plays a pivotal role in the thermodynamics of nonequilibrium processes with feedback. However, much remains to be learned about the nature of information fluctuations in small-scale devices and their relation with fluctuations in other thermodynamics quantities, like heat and work. Here we derive a series of fluctuation theorems for information flow and partial entropy production in a Brownian particle model of feedback cooling and extend them to arbitrary driven diffusion processes. We then analyze the long-time behavior of the feedback-cooling model in detail. Our results provide insights into the structure and origin of large deviations of information and thermodynamic quantities in autonomous Maxwell's demons.

  18. Separating intrinsic from extrinsic fluctuations in dynamic biological systems

    PubMed Central

    Paulsson, Johan

    2011-01-01

    From molecules in cells to organisms in ecosystems, biological populations fluctuate due to the intrinsic randomness of individual events and the extrinsic influence of changing environments. The combined effect is often too complex for effective analysis, and many studies therefore make simplifying assumptions, for example ignoring either intrinsic or extrinsic effects to reduce the number of model assumptions. Here we mathematically demonstrate how two identical and independent reporters embedded in a shared fluctuating environment can be used to identify intrinsic and extrinsic noise terms, but also how these contributions are qualitatively and quantitatively different from what has been previously reported. Furthermore, we show for which classes of biological systems the noise contributions identified by dual-reporter methods correspond to the noise contributions predicted by correct stochastic models of either intrinsic or extrinsic mechanisms. We find that for broad classes of systems, the extrinsic noise from the dual-reporter method can be rigorously analyzed using models that ignore intrinsic stochasticity. In contrast, the intrinsic noise can be rigorously analyzed using models that ignore extrinsic stochasticity only under very special conditions that rarely hold in biology. Testing whether the conditions are met is rarely possible and the dual-reporter method may thus produce flawed conclusions about the properties of the system, particularly about the intrinsic noise. Our results contribute toward establishing a rigorous framework to analyze dynamically fluctuating biological systems. PMID:21730172

  19. Separating intrinsic from extrinsic fluctuations in dynamic biological systems.

    PubMed

    Hilfinger, Andreas; Paulsson, Johan

    2011-07-19

    From molecules in cells to organisms in ecosystems, biological populations fluctuate due to the intrinsic randomness of individual events and the extrinsic influence of changing environments. The combined effect is often too complex for effective analysis, and many studies therefore make simplifying assumptions, for example ignoring either intrinsic or extrinsic effects to reduce the number of model assumptions. Here we mathematically demonstrate how two identical and independent reporters embedded in a shared fluctuating environment can be used to identify intrinsic and extrinsic noise terms, but also how these contributions are qualitatively and quantitatively different from what has been previously reported. Furthermore, we show for which classes of biological systems the noise contributions identified by dual-reporter methods correspond to the noise contributions predicted by correct stochastic models of either intrinsic or extrinsic mechanisms. We find that for broad classes of systems, the extrinsic noise from the dual-reporter method can be rigorously analyzed using models that ignore intrinsic stochasticity. In contrast, the intrinsic noise can be rigorously analyzed using models that ignore extrinsic stochasticity only under very special conditions that rarely hold in biology. Testing whether the conditions are met is rarely possible and the dual-reporter method may thus produce flawed conclusions about the properties of the system, particularly about the intrinsic noise. Our results contribute toward establishing a rigorous framework to analyze dynamically fluctuating biological systems.

  20. Application of VSC-HVDC with Shunt Connected SMES for Compensation of Power Fluctuation

    NASA Astrophysics Data System (ADS)

    Linn, Zarchi; Kakigano, Hiroaki; Miura, Yushi; Ise, Toshifumi

    This paper describes the application of VSC-HVDC (High Voltage DC Transmission using Voltage Source Converter) with shunt connected SMES (Superconducting Magnetic Energy Storage) for compensation of power fluctuation caused by fluctuating power source such as photovoltaics and wind turbines. The objectives of this proposed system is to smooth out fluctuating power in one terminal side of HVDC in order to avoid causing power system instability and frequency deviation by absorbing or providing power according to the system requirement while another terminal side power is fluctuated. The shunt connected SMES charges and discharges the energy to and from the dc side and it compensates required power of fluctuation to obtain constant power flow in one terminal side of VSC-HVDC system. This system configuration has ability for power system stabilization in the case of power fluctuation from natural energy source. PSCAD/EMTDC simulation is used to evaluate the performance of applied system configuration and control method.

  1. 30 CFR 250.1401 - Index table.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Index table. 250.1401 Section 250.1401 Mineral... OPERATIONS IN THE OUTER CONTINENTAL SHELF Outer Continental Shelf (OCS) Civil Penalties § 250.1401 Index table. The following table is an index of the sections in this subpart: § 250.1401Table Definitions...

  2. Do children with obesity have worse table manners? Associations between child table manners, weight status and weight gain.

    PubMed

    Briones, Naomi F; Cesaro, Robert J; Appugliese, Danielle P; Miller, Alison L; Rosenblum, Katherine L; Pesch, Megan H

    2018-06-01

    Children with obesity experience stigma stemming from stereotypes, one such stereotype is that people with obesity are "sloppy" or have poor manners. Teaching children "proper table manners" has been proposed as an obesity prevention strategy. Little is known about the association between children's weight status and table manners. To examine correlates of child table manners and to examine the association of child table manners with child obese weight status and prospective change in child body mass index z-score (BMIz). Mother-child dyads (N = 228) participated in a videotaped laboratory eating task with cupcakes. Coding schemes to capture child table manners (making crumbs, chewing with mouth open, getting food on face, shoving food in mouth, slouching, and getting out of seat), and maternal attentiveness to child table manners, were reliably applied. Anthropometrics were measured at baseline and at follow-up two years later. Regression analyses examined the association of participant characteristics with child table manners, as well as the associations of child table manners with child obese weight status, and prospective change in BMIz/year. Predictors of poorer child table manners were younger child age, greater cupcake consumption, and greater maternal attentiveness to child table manners. Poorer child table manners were not associated with child obese (vs. not) weight status, but were associated with a prospective decrease in BMIz/year in children with overweight/obesity. Obesity interventions to improve table manners may be perpetuating unfavorable stereotypes and stigma. Future work investigating these associations is warranted to inform childhood obesity guidelines around table manners. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Cloth-covered chiropractic treatment tables as a source of allergens and pathogenic microbes☆

    PubMed Central

    Evans, Marion W.; Campbell, Alan; Husbands, Chris; Breshears, Jennell; Ndetan, Harrison; Rupert, Ronald

    2008-01-01

    Abstract Objective Vinyl chiropractic tables have been found to harbor pathogenic bacteria, but wiping with a simple disinfection agent can significantly reduce the risk of bacteria. The aim of this study was to assess the presence of microbes and other allergens or pathogens on cloth chiropractic tables. Methods Cloth-covered tables in a chiropractic college teaching clinic were selected. Samples were taken from the facial piece and hand rests with RODAC plates containing nutrient agar, followed by confirmatory testing when indicated. Results Numerous microbacteria strains were found, including Staphylococcus aureus and Propionibacterium. Allergen-producing molds, including Candida, were also found. Conclusion Cloth tables were shown to contain pathogenic microbacteria and allergens. The chiropractic profession should establish an infection control protocol relevant to treatment tables and discard use of cloth-covered treatment tables in this process. PMID:19674718

  4. Resonant tunneling of fluctuation Cooper pairs

    DOE PAGES

    Galda, Alexey; Mel'nikov, A. S.; Vinokur, V. M.

    2015-02-09

    Superconducting fluctuations have proved to be an irreplaceable source of information about microscopic and macroscopic material parameters that could be inferred from the experiment. According to common wisdom, the effect of thermodynamic fluctuations in the vicinity of the superconducting transition temperature, T c, is to round off all of the sharp corners and discontinuities, which otherwise would have been expected to occur at T c. Here we report the current spikes due to radiation-induced resonant tunneling of fluctuation Cooper pairs between two superconductors which grow even sharper and more pronounced upon approach to T c. This striking effect offers anmore » unprecedented tool for direct measurements of fluctuation Cooper pair lifetime, which is key to our understanding of the fluctuation regime, most notably to nature of the pseudogap state in high-temperature superconductors. Lastly, our finding marks a radical departure from the conventional view of superconducting fluctuations as a blurring and rounding phenomenon.« less

  5. Empirical yield tables for Wisconsin.

    Treesearch

    Burton L. Essex; Jerold T. Hahn

    1976-01-01

    Describes the tables derived from the 1968 forest survey of Wisconsin. These tables are broken down according to Wisconsin's 5 Forest Survey Units, 12 forest types, and 5 site index classes. Presents 18 tables as examples of the more than 500 that can be ordered by using the order form enclosed in the publication.

  6. Rank and independence in contingency table

    NASA Astrophysics Data System (ADS)

    Tsumoto, Shusaku

    2004-04-01

    A contingency table summarizes the conditional frequencies of two attributes and shows how these two attributes are dependent on each other. Thus, this table is a fundamental tool for pattern discovery with conditional probabilities, such as rule discovery. In this paper, a contingency table is interpreted from the viewpoint of statistical independence and granular computing. The first important observation is that a contingency table compares two attributes with respect to the number of equivalence classes. For example, a n x n table compares two attributes with the same granularity, while a m x n(m >= n) table compares two attributes with different granularities. The second important observation is that matrix algebra is a key point of analysis of this table. Especially, the degree of independence, rank plays a very important role in evaluating the degree of statistical independence. Relations between rank and the degree of dependence are also investigated.

  7. Shadowgraph Study of Gradient Driven Fluctuations

    NASA Technical Reports Server (NTRS)

    Cannell, David; Nikolaenko, Gennady; Giglio, Marzio; Vailati, Alberto; Croccolo, Fabrizio; Meyer, William

    2002-01-01

    A fluid or fluid mixture, subjected to a vertical temperature and/or concentration gradient in a gravitational field, exhibits greatly enhanced light scattering at small angles. This effect is caused by coupling between the vertical velocity fluctuations due to thermal energy and the vertically varying refractive index. Physically, small upward or downward moving regions will be displaced into fluid having a refractive index different from that of the moving region, thus giving rise to the enhanced scattering. The scattered intensity is predicted to vary with scattering wave vector q, as q(sup -4), for sufficiently large q, but the divergence is quenched by gravity at small q. In the absence of gravity, the long wavelength fluctuations responsible for the enhanced scattering are predicted to grow until limited by the sample dimensions. It is thus of interest to measure the mean-squared amplitude of such fluctuations in the microgravity environment for comparison with existing theory and ground based measurements. The relevant wave vectors are extremely small, making traditional low-angle light scattering difficult or impossible because of stray elastically scattered light generated by optical surfaces. An alternative technique is offered by the shadowgraph method, which is normally used to visualize fluid flows, but which can also serve as a quantitative tool to measure fluctuations. A somewhat novel shadowgraph apparatus and the necessary data analysis methods will be described. The apparatus uses a spatially coherent, but temporally incoherent, light source consisting of a super-luminescent diode coupled to a single-mode optical fiber in order to achieve extremely high spatial resolution, while avoiding effects caused by interference of light reflected from the various optical surfaces that are present when using laser sources. Results obtained for a critical mixture of aniline and cyclohexane subjected to a vertical temperature gradient will be presented. The

  8. 40 CFR Table 4 of Subpart Aaaa to... - Requirements for Continuous Emission Monitoring Systems (CEMS)

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Monitoring Systems (CEMS) 4 Table 4 of Subpart AAAA to Part 60 Protection of Environment ENVIRONMENTAL.... 60, Subpt. AAAA, Table 4 Table 4 of Subpart AAAA to Part 60—Requirements for Continuous Emission... unit P.S. 2 Method 6C. 4. Carbon Monoxide 125 percent of the maximum expected hourly potential carbon...

  9. 26 CFR 1.461-0 - Table of contents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Payment liabilities. (l) [Reserved] (m) Change in method of accounting required by this section. (1) In general. (2) Change in method of accounting for long-term contracts and payment liabilities. § 1.461... 26 Internal Revenue 6 2010-04-01 2010-04-01 false Table of contents. 1.461-0 Section 1.461-0...

  10. Spectral properties of thermal fluctuations on simple liquid surfaces below shot-noise levels.

    PubMed

    Aoki, Kenichiro; Mitsui, Takahisa

    2012-07-01

    We study the spectral properties of thermal fluctuations on simple liquid surfaces, sometimes called ripplons. Analytical properties of the spectral function are investigated and are shown to be composed of regions with simple analytic behavior with respect to the frequency or the wave number. The derived expressions are compared to spectral measurements performed orders of magnitude below shot-noise levels, which is achieved using a novel noise reduction method. The agreement between the theory of thermal surface fluctuations and the experiment is found to be excellent, elucidating the spectral properties of the surface fluctuations. The measurement method requires relatively only a small sample both spatially (few μm) and temporally (~20 s). The method also requires relatively weak light power (~0.5 mW) so that it has a broad range of applicability, including local measurements, investigations of time-dependent phenomena, and noninvasive measurements.

  11. 40 CFR Table 15 to Subpart G of... - Wastewater-Information on Table 8 and/or Table 9 Compounds To Be Submitted With Notification of...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Wastewater-Information on Table 8 and... Operations, and Wastewater Pt. 63, Subpt. G, Table 15 Table 15 to Subpart G of Part 63—Wastewater—Information... specified in § 63.132 (c) or (d) and § 63.144. e When § 63.132(e) is used, indicate the wastewater stream is...

  12. 40 CFR Table 15 to Subpart G of... - Wastewater-Information on Table 8 and/or Table 9 Compounds To Be Submitted With Notification of...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Wastewater-Information on Table 8 and... Operations, and Wastewater Pt. 63, Subpt. G, Table 15 Table 15 to Subpart G of Part 63—Wastewater—Information... specified in § 63.132 (c) or (d) and § 63.144. e When § 63.132(e) is used, indicate the wastewater stream is...

  13. 40 CFR Table 15 to Subpart G of... - Wastewater-Information on Table 8 and/or Table 9 Compounds To Be Submitted With Notification of...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Wastewater-Information on Table 8 and... Operations, and Wastewater Pt. 63, Subpt. G, Table 15 Table 15 to Subpart G of Part 63—Wastewater—Information... specified in § 63.132 (c) or (d) and § 63.144. e When § 63.132(e) is used, indicate the wastewater stream is...

  14. 40 CFR Table 15 to Subpart G of... - Wastewater-Information on Table 8 and/or Table 9 Compounds To Be Submitted With Notification of...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Wastewater-Information on Table 8 and... Operations, and Wastewater Pt. 63, Subpt. G, Table 15 Table 15 to Subpart G of Part 63—Wastewater—Information... specified in § 63.132 (c) or (d) and § 63.144. e When § 63.132(e) is used, indicate the wastewater stream is...

  15. 40 CFR Table 15 to Subpart G of... - Wastewater-Information on Table 8 and/or Table 9 Compounds To Be Submitted With Notification of...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Wastewater-Information on Table 8 and... Operations, and Wastewater Pt. 63, Subpt. G, Table 15 Table 15 to Subpart G of Part 63—Wastewater—Information... specified in § 63.132 (c) or (d) and § 63.144. e When § 63.132(e) is used, indicate the wastewater stream is...

  16. Taper tables for western hemlock.

    Treesearch

    Floyd A. Johnson; Wilbur Engstrom

    1949-01-01

    In 1947 the West Coast Forestry procedures Committee recommended several mensuration projects, one of which called for the construction of taper tables for Western hemlock. In response the present tables were prepared. Basic data for these tables consist of measurements of 912 trees taken a number of years ago by members of the Pacific Northwest Forest & Range...

  17. Measurements of the driving forces of bio-motors using the fluctuation theorem

    PubMed Central

    Hayashi, Kumiko; Tanigawara, Mizue; Kishikawa, Jun-ichi

    2012-01-01

    The fluctuation theorem (FT), which is a recent achievement in non-equilibrium statistical mechanics, has been suggested to be useful for measuring the driving forces of motor proteins. As an example of this application, we performed single-molecule experiments on F1-ATPase, which is a rotary motor protein, in which we measured its rotary torque by taking advantage of FT. Because fluctuation is inherent nature in biological small systems and because FT is a non-destructive force measurement method using fluctuation, it will be applied to a wide range of biological small systems in future. PMID:27857609

  18. Event-shape fluctuations and flow correlations in ultra-relativistic heavy-ion collisions

    DOE PAGES

    Jia, Jiangyong

    2014-12-01

    I review recent measurements of a large set of flow observables associated with event-shape fluctuations and collective expansion in heavy ion collisions. First, these flow observables are classified and experiment methods are introduced. The experimental results for each type of observables are then presented and compared to theoretical calculations. A coherent picture of initial condition and collective flow based on linear and non-linear hydrodynamic responses is derived, which qualitatively describe most experimental results. I discuss new types of fluctuation measurements that can further our understanding of the event-shape fluctuations and collective expansion dynamics.

  19. A comparison of hierarchical cluster analysis and league table rankings as methods for analysis and presentation of district health system performance data in Uganda.

    PubMed

    Tashobya, Christine K; Dubourg, Dominique; Ssengooba, Freddie; Speybroeck, Niko; Macq, Jean; Criel, Bart

    2016-03-01

    In 2003, the Uganda Ministry of Health introduced the district league table for district health system performance assessment. The league table presents district performance against a number of input, process and output indicators and a composite index to rank districts. This study explores the use of hierarchical cluster analysis for analysing and presenting district health systems performance data and compares this approach with the use of the league table in Uganda. Ministry of Health and district plans and reports, and published documents were used to provide information on the development and utilization of the Uganda district league table. Quantitative data were accessed from the Ministry of Health databases. Statistical analysis using SPSS version 20 and hierarchical cluster analysis, utilizing Wards' method was used. The hierarchical cluster analysis was conducted on the basis of seven clusters determined for each year from 2003 to 2010, ranging from a cluster of good through moderate-to-poor performers. The characteristics and membership of clusters varied from year to year and were determined by the identity and magnitude of performance of the individual variables. Criticisms of the league table include: perceived unfairness, as it did not take into consideration district peculiarities; and being oversummarized and not adequately informative. Clustering organizes the many data points into clusters of similar entities according to an agreed set of indicators and can provide the beginning point for identifying factors behind the observed performance of districts. Although league table ranking emphasize summation and external control, clustering has the potential to encourage a formative, learning approach. More research is required to shed more light on factors behind observed performance of the different clusters. Other countries especially low-income countries that share many similarities with Uganda can learn from these experiences. © The Author 2015

  20. A comparison of hierarchical cluster analysis and league table rankings as methods for analysis and presentation of district health system performance data in Uganda†

    PubMed Central

    Tashobya, Christine K; Dubourg, Dominique; Ssengooba, Freddie; Speybroeck, Niko; Macq, Jean; Criel, Bart

    2016-01-01

    In 2003, the Uganda Ministry of Health introduced the district league table for district health system performance assessment. The league table presents district performance against a number of input, process and output indicators and a composite index to rank districts. This study explores the use of hierarchical cluster analysis for analysing and presenting district health systems performance data and compares this approach with the use of the league table in Uganda. Ministry of Health and district plans and reports, and published documents were used to provide information on the development and utilization of the Uganda district league table. Quantitative data were accessed from the Ministry of Health databases. Statistical analysis using SPSS version 20 and hierarchical cluster analysis, utilizing Wards’ method was used. The hierarchical cluster analysis was conducted on the basis of seven clusters determined for each year from 2003 to 2010, ranging from a cluster of good through moderate-to-poor performers. The characteristics and membership of clusters varied from year to year and were determined by the identity and magnitude of performance of the individual variables. Criticisms of the league table include: perceived unfairness, as it did not take into consideration district peculiarities; and being oversummarized and not adequately informative. Clustering organizes the many data points into clusters of similar entities according to an agreed set of indicators and can provide the beginning point for identifying factors behind the observed performance of districts. Although league table ranking emphasize summation and external control, clustering has the potential to encourage a formative, learning approach. More research is required to shed more light on factors behind observed performance of the different clusters. Other countries especially low-income countries that share many similarities with Uganda can learn from these experiences. PMID:26024882

  1. Chaotic Dynamical Ferromagnetic Phase Induced by Nonequilibrium Quantum Fluctuations.

    PubMed

    Lerose, Alessio; Marino, Jamir; Žunkovič, Bojan; Gambassi, Andrea; Silva, Alessandro

    2018-03-30

    We investigate the robustness of a dynamical phase transition against quantum fluctuations by studying the impact of a ferromagnetic nearest-neighbor spin interaction in one spatial dimension on the nonequilibrium dynamical phase diagram of the fully connected quantum Ising model. In particular, we focus on the transient dynamics after a quantum quench and study the prethermal state via a combination of analytic time-dependent spin wave theory and numerical methods based on matrix product states. We find that, upon increasing the strength of the quantum fluctuations, the dynamical critical point fans out into a chaotic dynamical phase within which the asymptotic ordering is characterized by strong sensitivity to the parameters and initial conditions. We argue that such a phenomenon is general, as it arises from the impact of quantum fluctuations on the mean-field out of equilibrium dynamics of any system which exhibits a broken discrete symmetry.

  2. Chaotic Dynamical Ferromagnetic Phase Induced by Nonequilibrium Quantum Fluctuations

    NASA Astrophysics Data System (ADS)

    Lerose, Alessio; Marino, Jamir; Žunkovič, Bojan; Gambassi, Andrea; Silva, Alessandro

    2018-03-01

    We investigate the robustness of a dynamical phase transition against quantum fluctuations by studying the impact of a ferromagnetic nearest-neighbor spin interaction in one spatial dimension on the nonequilibrium dynamical phase diagram of the fully connected quantum Ising model. In particular, we focus on the transient dynamics after a quantum quench and study the prethermal state via a combination of analytic time-dependent spin wave theory and numerical methods based on matrix product states. We find that, upon increasing the strength of the quantum fluctuations, the dynamical critical point fans out into a chaotic dynamical phase within which the asymptotic ordering is characterized by strong sensitivity to the parameters and initial conditions. We argue that such a phenomenon is general, as it arises from the impact of quantum fluctuations on the mean-field out of equilibrium dynamics of any system which exhibits a broken discrete symmetry.

  3. RADIOACTIVE ELEMENTS IN THE STANDARD ATOMIC WEIGHTS TABLE

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

    Holden, N.E.; Holden, N.; Holden,N.E.

    2011-07-27

    In the 1949 Report of the Atomic Weights Commission, a series of new elements were added to the Atomic Weights Table. Since these elements had been produced in the laboratory and were not discovered in nature, the atomic weight value of these artificial products would depend upon the production method. Since atomic weight is a property of an element as it occurs in nature, it would be incorrect to assign an atomic weight value to that element. As a result of that discussion, the Commission decided to provide only the mass number of the most stable (or longest-lived) known isotopemore » as the number to be associated with these entries in the Atomic Weights Table. As a function of time, the mass number associated with various elements has changed as longer-lived isotopes of a particular element has been found in nature, or as improved half-life values of an element's isotopes might cause a shift in the longest-lived isotope from one mass to another. In the 1957 Report of the Atomic Weights Commission, it was decided to discontinue the listing of the mass number in the Atomic Weights Table on the grounds that the kind of information supplied by the mass number is inconsistent with the primary purpose of the Table, i.e., to provide accurate values of 'these constants' for use in various chemical calculations. In addition to the Table of Atomic Weights, the Commission included an auxiliary Table of Radioactive Elements for the first time, where the entry would be the isotope of that element which was the most stable, i.e., the one with the longest known half-life. In their 1973 Report, the Commission noted that the users of the main Table of Atomic Weights were dissatisfied with the omission of values for some elements in that Table and it was decided to reintroduce the mass number for the radioactive elements into the main Table. In their 1983 Report, the Commission decided that radioactive elements were considered to lack a characteristic terrestrial isotopic

  4. 40 CFR Table 4 of Subpart Aaaa of... - Requirements for Continuous Emission Monitoring Systems (CEMS)

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Monitoring Systems (CEMS) 4 Table 4 of Subpart AAAA of Part 60 Protection of Environment ENVIRONMENTAL... Definitions What definitions must I know? Pt. 60, Subpt. AAAA, Table 4 Table 4 of Subpart AAAA of Part 60... dioxide emissions of the municipal waste combustion unit P.S. 2 Method 6C. 4. Carbon Monoxide 125 percent...

  5. 40 CFR Table 4 of Subpart Aaaa of... - Requirements for Continuous Emission Monitoring Systems (CEMS)

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Monitoring Systems (CEMS) 4 Table 4 of Subpart AAAA of Part 60 Protection of Environment ENVIRONMENTAL... Definitions What definitions must I know? Pt. 60, Subpt. AAAA, Table 4 Table 4 of Subpart AAAA of Part 60... dioxide emissions of the municipal waste combustion unit P.S. 2 Method 6C. 4. Carbon Monoxide 125 percent...

  6. Life expectancy--a commentary on this life table variable.

    PubMed

    Singer, Richard B

    2005-01-01

    In 1992, I wrote an article on a method of modifying the Decennial US Life Table to accommodate any pattern of excess mortality expressed in terms of excess death rate (EDR), for the specific purpose of calculating the reduced life expectancy, e. I believe this was the first article published in the Journal of Insurance Medicine (JIM) that dealt specifically with life expectancy as an index of survival and risk appraisal, never used in the classification of extra mortality risk in applicants for life insurance. In this commentary, I discuss the 1989-91 US Decennial Life Table in detail. I link the subject matter of the 1992 article with several more recent articles that also focus on the utility of life expectancy in underwriting structured settlement annuities and preparing reports on life expectancy for an attorney in a tort case. A few references are given for further reading on life table methodology and its use in the most accurate estimate of life expectancy, given the inherent limitations of the life table and the limited duration of follow-up studies.

  7. Current Fluctuations in Stochastic Lattice Gases

    NASA Astrophysics Data System (ADS)

    Bertini, L.; de Sole, A.; Gabrielli, D.; Jona-Lasinio, G.; Landim, C.

    2005-01-01

    We study current fluctuations in lattice gases in the macroscopic limit extending the dynamic approach for density fluctuations developed in previous articles. More precisely, we establish a large deviation theory for the space-time fluctuations of the empirical current which include the previous results. We then estimate the probability of a fluctuation of the average current over a large time interval. It turns out that recent results by Bodineau and Derrida [Phys. Rev. Lett.922004180601] in certain cases underestimate this probability due to the occurrence of dynamical phase transitions.

  8. The entropy of the life table: A reappraisal.

    PubMed

    Fernandez, Oscar E; Beltrán-Sánchez, Hiram

    2015-09-01

    The life table entropy provides useful information for understanding improvements in mortality and survival in a population. In this paper we take a closer look at the life table entropy and use advanced mathematical methods to provide additional insights for understanding how it relates to changes in mortality and survival. By studying the entropy (H) as a functional, we show that changes in the entropy depend on both the relative change in life expectancy lost due to death (e(†)) and in life expectancy at birth (e0). We also show that changes in the entropy can be further linked to improvements in premature and older deaths. We illustrate our methods with empirical data from Latin American countries, which suggests that at high mortality levels declines in H (which are associated with survival increases) linked with larger improvements in e0, whereas at low mortality levels e(†) made larger contributions to H. We additionally show that among countries with low mortality level, contributions of e(†) to changes in the life table entropy resulted from averting early deaths. These findings indicate that future increases in overall survival in low mortality countries will likely result from improvements in e(†). Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Volume and taper tables for red alder.

    Treesearch

    Robert O. Curtis; David Bruce; Caryanne VanCoevering

    1968-01-01

    Red alder is a species of increasing importance in the Pacific Northwest. Interest in improved volume tables for the species resulted in publication of the 1949 volume tables. More recently, Browne (1962) published cubic-foot-volume tables for red alder in British Columbia, and Hoyer (1966) presented tarif access tables, based on the 1949 tables, for use with the...

  10. Analysis of fluctuations in semiconductor devices

    NASA Astrophysics Data System (ADS)

    Andrei, Petru

    The random nature of ion implantation and diffusion processes as well as inevitable tolerances in fabrication result in random fluctuations of doping concentrations and oxide thickness in semiconductor devices. These fluctuations are especially pronounced in ultrasmall (nanoscale) semiconductor devices when the spatial scale of doping and oxide thickness variations become comparable with the geometric dimensions of devices. In the dissertation, the effects of these fluctuations on device characteristics are analyzed by using a new technique for the analysis of random doping and oxide thickness induced fluctuations. This technique is universal in nature in the sense that it is applicable to any transport model (drift-diffusion, semiclassical transport, quantum transport etc.) and it can be naturally extended to take into account random fluctuations of the oxide (trapped) charges and channel length. The technique is based on linearization of the transport equations with respect to the fluctuating quantities. It is computationally much (a few orders of magnitude) more efficient than the traditional Monte-Carlo approach and it yields information on the sensitivity of fluctuations of parameters of interest (e.g. threshold voltage, small-signal parameters, cut-off frequencies, etc.) to the locations of doping and oxide thickness fluctuations. For this reason, it can be very instrumental in the design of fluctuation-resistant structures of semiconductor devices. Quantum mechanical effects are taken into account by using the density-gradient model as well as through self-consistent Poisson-Schrodinger computations. Special attention is paid to the presenting of the technique in a form that is suitable for implementation on commercial device simulators. The numerical implementation of the technique is discussed in detail and numerous computational results are presented and compared with those previously published in literature.

  11. The multiple decrement life table: a unifying framework for cause-of-death analysis in ecology.

    PubMed

    Carey, James R

    1989-01-01

    The multiple decrement life table is used widely in the human actuarial literature and provides statistical expressions for mortality in three different forms: i) the life table from all causes-of-death combined; ii) the life table disaggregated into selected cause-of-death categories; and iii) the life table with particular causes and combinations of causes eliminated. The purpose of this paper is to introduce the multiple decrement life table to the ecological literature by applying the methods to published death-by-cause information on Rhagoletis pomonella. Interrelations between the current approach and conventional tools used in basic and applied ecology are discussed including the conventional life table, Key Factor Analysis and Abbott's Correction used in toxicological bioassay.

  12. Analysis of dynamic multiplicity fluctuations at PHOBOS

    NASA Astrophysics Data System (ADS)

    Chai, Zhengwei; PHOBOS Collaboration; Back, B. B.; Baker, M. D.; Ballintijn, M.; Barton, D. S.; Betts, R. R.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Chai, Z.; Decowski, M. P.; García, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Holynski, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steinberg, P.; Stephans, G. S. F.; Sukhanov, A.; Tang, J. L.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wolfs, F. L. H.; Wosiek, B.; Wozniak, K.; Wuosmaa, A. H.; Wyslouch, B.

    2005-01-01

    This paper presents the analysis of the dynamic fluctuations in the inclusive charged particle multiplicity measured by PHOBOS for Au+Au collisions at surdsNN = 200GeV within the pseudo-rapidity range of -3 < η < 3. First the definition of the fluctuations observables used in this analysis is presented, together with the discussion of their physics meaning. Then the procedure for the extraction of dynamic fluctuations is described. Some preliminary results are included to illustrate the correlation features of the fluctuation observable. New dynamic fluctuations results will be available in a later publication.

  13. Amplification of intrinsic fluctuations by the Lorenz equations

    NASA Astrophysics Data System (ADS)

    Fox, Ronald F.; Elston, T. C.

    1993-07-01

    Macroscopic systems (e.g., hydrodynamics, chemical reactions, electrical circuits, etc.) manifest intrinsic fluctuations of molecular and thermal origin. When the macroscopic dynamics is deterministically chaotic, the intrinsic fluctuations may become amplified by several orders of magnitude. Numerical studies of this phenomenon are presented in detail for the Lorenz model. Amplification to macroscopic scales is exhibited, and quantitative methods (binning and a difference-norm) are presented for measuring macroscopically subliminal amplification effects. In order to test the quality of the numerical results, noise induced chaos is studied around a deterministically nonchaotic state, where the scaling law relating the Lyapunov exponent to noise strength obtained for maps is confirmed for the Lorenz model, a system of ordinary differential equations.

  14. Fluctuations in epidemic modeling - disease extinction and control

    NASA Astrophysics Data System (ADS)

    Schwartz, Ira

    2009-03-01

    The analysis of infectious disease fluctuations has recently seen an increasing rise in the use of new tools and models from stochastic dynamics and statistical physics. Examples arise in modeling fluctuations of multi-strain diseases, in modeling adaptive social behavior and its impact on disease fluctuations, and in the analysis of disease extinction in finite population models. Proper stochastic model reduction [1] allows one to predict unobserved fluctuations from observed data in multi-strain models [2]. Degree alteration and power law behavior is predicted in adaptive network epidemic models [3,4]. And extinction rates derived from large fluctuation theory exhibit scaling with respect to distance to the bifurcation point of disease onset with an unusual exponent [5]. In addition to outbreak prediction, another main goal of epidemic modeling is one of eliminating the disease to extinction through various control mechanisms, such as vaccine implementation or quarantine. In this talk, a description will be presented of the fluctuational behavior of several epidemic models and their extinction rates. A general framework and analysis of the effect of non-Gaussian control actuations which enhance the rate to disease extinction will be described. In particular, in it is shown that even in the presence of a small Poisson distributed vaccination program, there is an exponentially enhanced rate to disease extinction. These ideas may lead to improved methods of controlling disease where random vaccinations are prevalent. [4pt] Recent papers:[0pt] [1] E. Forgoston and I. B. Schwartz, ``Escape Rates in a Stochastic Environment with Multiple Scales,'' arXiv:0809.1345 2008.[0pt] [2] L. B. Shaw, L. Billings, I. B. Schwartz, ``Using dimension reduction to improve outbreak predictability of multi-strain diseases,'' J. Math. Bio. 55, 1 2007.[0pt] [3] L. B. Shaw and I. B. Schwartz, ``Fluctuating epidemics on adaptive networks,'' Physical Review E 77, 066101 2008.[0pt] [4] L. B

  15. Evolutionary dynamics of fluctuating populations with strong mutualism

    NASA Astrophysics Data System (ADS)

    Chotibut, Thiparat; Nelson, David

    2013-03-01

    Evolutionary game theory with finite interacting populations is receiving increased attention, including subtle phenomena associated with number fluctuations, i.e., ``genetic drift.'' Models of cooperation and competition often utilize a simplified Moran model, with a strictly fixed total population size. We explore a more general evolutionary model with independent fluctuations in the numbers of two distinct species, in a regime characterized by ``strong mutualism.'' The model has two absorbing states, each corresponding to fixation of one of the two species, and allows exploration of the interplay between growth, competition, and mutualism. When mutualism is favored, number fluctuations eventually drive the system away from a stable fixed point, characterized by cooperation, to one of the absorbing states. Well-mixed populations will thus be taken over by a single species in a finite time, despite the bias towards cooperation. We calculate both the fixation probability and the mean fixation time as a function of the initial conditions and carrying capacities in the strong mutualism regime, using the method of matched asymptotic expansions. Our results are compared to computer simulations.

  16. Ecological periodic tables for nekton and benthic macrofaunal community usage of estuarine habitats Slides

    EPA Science Inventory

    Ecological periodic tables for nekton and benthic macrofaunal community usage of estuarine habitats Steven P. Ferraro, U.S. Environmental Protection Agency, Newport, OR Background/Questions/Methods The chemical periodic table, the Linnaean system of classification, and the Her...

  17. Fluctuation Scaling, Taylor’s Law, and Crime

    PubMed Central

    Hanley, Quentin S.; Khatun, Suniya; Yosef, Amal; Dyer, Rachel-May

    2014-01-01

    Fluctuation scaling relationships have been observed in a wide range of processes ranging from internet router traffic to measles cases. Taylor’s law is one such scaling relationship and has been widely applied in ecology to understand communities including trees, birds, human populations, and insects. We show that monthly crime reports in the UK show complex fluctuation scaling which can be approximated by Taylor’s law relationships corresponding to local policing neighborhoods and larger regional and countrywide scales. Regression models applied to local scale data from Derbyshire and Nottinghamshire found that different categories of crime exhibited different scaling exponents with no significant difference between the two regions. On this scale, violence reports were close to a Poisson distribution (α = 1.057±0.026) while burglary exhibited a greater exponent (α = 1.292±0.029) indicative of temporal clustering. These two regions exhibited significantly different pre-exponential factors for the categories of anti-social behavior and burglary indicating that local variations in crime reports can be assessed using fluctuation scaling methods. At regional and countrywide scales, all categories exhibited scaling behavior indicative of temporal clustering evidenced by Taylor’s law exponents from 1.43±0.12 (Drugs) to 2.094±0081 (Other Crimes). Investigating crime behavior via fluctuation scaling gives insight beyond that of raw numbers and is unique in reporting on all processes contributing to the observed variance and is either robust to or exhibits signs of many types of data manipulation. PMID:25271781

  18. High temporal resolution modeling of the impact of rain, tides, and sea level rise on water table flooding in the Arch Creek basin, Miami-Dade County Florida USA.

    PubMed

    Sukop, Michael C; Rogers, Martina; Guannel, Greg; Infanti, Johnna M; Hagemann, Katherine

    2018-03-01

    Modeling of groundwater levels in a portion of the low-lying coastal Arch Creek basin in northern Miami-Dade County in Southeast Florida USA, which is subject to repetitive flooding, reveals that rain-induced short-term water table rises can be viewed as a primary driver of flooding events under current conditions. Areas below 0.9m North American Vertical Datum (NAVD) elevation are particularly vulnerable and areas below 1.5m NAVD are vulnerable to exceptionally large rainfall events. Long-term water table rise is evident in the groundwater data, and the rate appears to be consistent with local rates of sea level rise. Linear extrapolation of long-term observed groundwater levels to 2060 suggest roughly a doubling of the number of days when groundwater levels exceed 0.9m NAVD and a threefold increase in the number of days when levels exceed 1.5m NAVD. Projected sea level rise of 0.61m by 2060 together with increased rainfall lead to a model prediction of frequent groundwater-related flooding in areas<0.9m NAVD. However, current simulations do not consider the range of rainfall events that have led to water table elevations>1.5m NAVD and widespread flooding of the area in the past. Tidal fluctuations in the water table are predicted to be more pronounced within 600m of a tidally influenced water control structure that is hydrodynamically connected to Biscayne Bay. The inland influence of tidal fluctuations appears to increase with increased sea level, but the principal driver of high groundwater levels under the 2060 scenario conditions remains groundwater recharge due to rainfall events. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Visualizing period fluctuations in strained-layer superlattices with scanning tunneling microscopy

    NASA Astrophysics Data System (ADS)

    Kanedy, K.; Lopez, F.; Wood, M. R.; Gmachl, C. F.; Weimer, M.; Klem, J. F.; Hawkins, S. D.; Shaner, E. A.; Kim, J. K.

    2018-01-01

    We show how cross-sectional scanning tunneling microscopy (STM) may be used to accurately map the period fluctuations throughout epitaxial, strained-layer superlattices based on the InAs/InAsSb and InGaAs/InAlAs material systems. The concept, analogous to Bragg's law in high-resolution x-ray diffraction, relies on an analysis of the [001]-convolved reciprocal-space satellite peaks obtained from discrete Fourier transforms of individual STM images. Properly implemented, the technique enables local period measurements that reliably discriminate vertical fluctuations localized to within ˜5 superlattice repeats along the [001] growth direction and orthogonal, lateral fluctuations localized to within ˜40 nm along <110> directions in the growth plane. While not as accurate as x-ray, the inherent, single-image measurement error associated with the method may be made as small as 0.1%, allowing the vertical or lateral period fluctuations contributing to inhomogeneous energy broadening and carrier localization in these structures to be pinpointed and quantified. The direct visualization of unexpectedly large, lateral period fluctuations on nanometer length scales in both strain-balanced systems supports a common understanding in terms of correlated interface roughness.

  20. Electric Field Fluctuations in Water

    NASA Astrophysics Data System (ADS)

    Thorpe, Dayton; Limmer, David; Chandler, David

    2013-03-01

    Charge transfer in solution, such as autoionization and ion pair dissociation in water, is governed by rare electric field fluctuations of the solvent. Knowing the statistics of such fluctuations can help explain the dynamics of these rare events. Trajectories short enough to be tractable by computer simulation are virtually certain not to sample the large fluctuations that promote rare events. Here, we employ importance sampling techniques with classical molecular dynamics simulations of liquid water to study statistics of electric field fluctuations far from their means. We find that the distributions of electric fields located on individual water molecules are not in general gaussian. Near the mean this non-gaussianity is due to the internal charge distribution of the water molecule. Further from the mean, however, there is a previously unreported Bjerrum-like defect that stabilizes certain large fluctuations out of equilibrium. As expected, differences in electric fields acting between molecules are gaussian to a remarkable degree. By studying these differences, though, we are able to determine what configurations result not only in large electric fields, but also in electric fields with long spatial correlations that may be needed to promote charge separation.

  1. Stochastic level-set variational implicit-solvent approach to solute-solvent interfacial fluctuations

    PubMed Central

    Zhou, Shenggao; Sun, Hui; Cheng, Li-Tien; Dzubiella, Joachim; McCammon, J. Andrew

    2016-01-01

    Recent years have seen the initial success of a variational implicit-solvent model (VISM), implemented with a robust level-set method, in capturing efficiently different hydration states and providing quantitatively good estimation of solvation free energies of biomolecules. The level-set minimization of the VISM solvation free-energy functional of all possible solute-solvent interfaces or dielectric boundaries predicts an equilibrium biomolecular conformation that is often close to an initial guess. In this work, we develop a theory in the form of Langevin geometrical flow to incorporate solute-solvent interfacial fluctuations into the VISM. Such fluctuations are crucial to biomolecular conformational changes and binding process. We also develop a stochastic level-set method to numerically implement such a theory. We describe the interfacial fluctuation through the “normal velocity” that is the solute-solvent interfacial force, derive the corresponding stochastic level-set equation in the sense of Stratonovich so that the surface representation is independent of the choice of implicit function, and develop numerical techniques for solving such an equation and processing the numerical data. We apply our computational method to study the dewetting transition in the system of two hydrophobic plates and a hydrophobic cavity of a synthetic host molecule cucurbit[7]uril. Numerical simulations demonstrate that our approach can describe an underlying system jumping out of a local minimum of the free-energy functional and can capture dewetting transitions of hydrophobic systems. In the case of two hydrophobic plates, we find that the wavelength of interfacial fluctuations has a strong influence to the dewetting transition. In addition, we find that the estimated energy barrier of the dewetting transition scales quadratically with the inter-plate distance, agreeing well with existing studies of molecular dynamics simulations. Our work is a first step toward the

  2. Terrestrial Gravity Fluctuations

    NASA Astrophysics Data System (ADS)

    Harms, Jan

    2015-12-01

    Different forms of fluctuations of the terrestrial gravity field are observed by gravity experiments. For example, atmospheric pressure fluctuations generate a gravity-noise foreground in measurements with super-conducting gravimeters. Gravity changes caused by high-magnitude earthquakes have been detected with the satellite gravity experiment GRACE, and we expect high-frequency terrestrial gravity fluctuations produced by ambient seismic fields to limit the sensitivity of ground-based gravitational-wave (GW) detectors. Accordingly, terrestrial gravity fluctuations are considered noise and signal depending on the experiment. Here, we will focus on ground-based gravimetry. This field is rapidly progressing through the development of GW detectors. The technology is pushed to its current limits in the advanced generation of the LIGO and Virgo detectors, targeting gravity strain sensitivities better than 10-23 Hz-1/2 above a few tens of a Hz. Alternative designs for GW detectors evolving from traditional gravity gradiometers such as torsion bars, atom interferometers, and superconducting gradiometers are currently being developed to extend the detection band to frequencies below 1 Hz. The goal of this article is to provide the analytical framework to describe terrestrial gravity perturbations in these experiments. Models of terrestrial gravity perturbations related to seismic fields, atmospheric disturbances, and vibrating, rotating or moving objects, are derived and analyzed. The models are then used to evaluate passive and active gravity noise mitigation strategies in GW detectors, or alternatively, to describe their potential use in geophysics. The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our understanding of

  3. Terrestrial Gravity Fluctuations.

    PubMed

    Harms, Jan

    2015-01-01

    Different forms of fluctuations of the terrestrial gravity field are observed by gravity experiments. For example, atmospheric pressure fluctuations generate a gravity-noise foreground in measurements with super-conducting gravimeters. Gravity changes caused by high-magnitude earthquakes have been detected with the satellite gravity experiment GRACE, and we expect high-frequency terrestrial gravity fluctuations produced by ambient seismic fields to limit the sensitivity of ground-based gravitational-wave (GW) detectors. Accordingly, terrestrial gravity fluctuations are considered noise and signal depending on the experiment. Here, we will focus on ground-based gravimetry. This field is rapidly progressing through the development of GW detectors. The technology is pushed to its current limits in the advanced generation of the LIGO and Virgo detectors, targeting gravity strain sensitivities better than 10 -23 Hz -1/2 above a few tens of a Hz. Alternative designs for GW detectors evolving from traditional gravity gradiometers such as torsion bars, atom interferometers, and superconducting gradiometers are currently being developed to extend the detection band to frequencies below 1 Hz. The goal of this article is to provide the analytical framework to describe terrestrial gravity perturbations in these experiments. Models of terrestrial gravity perturbations related to seismic fields, atmospheric disturbances, and vibrating, rotating or moving objects, are derived and analyzed. The models are then used to evaluate passive and active gravity noise mitigation strategies in GW detectors, or alternatively, to describe their potential use in geophysics. The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our understanding of

  4. Frontiers in Fluctuation Spectroscopy: Measuring protein dynamics and protein spatio-temporal connectivity

    NASA Astrophysics Data System (ADS)

    Digman, Michelle

    Fluorescence fluctuation spectroscopy has evolved from single point detection of molecular diffusion to a family of microscopy imaging correlation tools (i.e. ICS, RICS, STICS, and kICS) useful in deriving spatial-temporal dynamics of proteins in living cells The advantage of the imaging techniques is the simultaneous measurement of all points in an image with a frame rate that is increasingly becoming faster with better sensitivity cameras and new microscopy modalities such as the sheet illumination technique. A new frontier in this area is now emerging towards a high level of mapping diffusion rates and protein dynamics in the 2 and 3 dimensions. In this talk, I will discuss the evolution of fluctuation analysis from the single point source to mapping diffusion in whole cells and the technology behind this technique. In particular, new methods of analysis exploit correlation of molecular fluctuations originating from measurement of fluctuation correlations at distant points (pair correlation analysis) and methods that exploit spatial averaging of fluctuations in small regions (iMSD). For example the pair correlation fluctuation (pCF) analyses done between adjacent pixels in all possible radial directions provide a window into anisotropic molecular diffusion. Similar to the connectivity atlas of neuronal connections from the MRI diffusion tensor imaging these new tools will be used to map the connectome of protein diffusion in living cells. For biological reaction-diffusion systems, live single cell spatial-temporal analysis of protein dynamics provides a mean to observe stochastic biochemical signaling in the context of the intracellular environment which may lead to better understanding of cancer cell invasion, stem cell differentiation and other fundamental biological processes. National Institutes of Health Grant P41-RRO3155.

  5. Insects in fluctuating thermal environments.

    PubMed

    Colinet, Hervé; Sinclair, Brent J; Vernon, Philippe; Renault, David

    2015-01-07

    All climate change scenarios predict an increase in both global temperature means and the magnitude of seasonal and diel temperature variation. The nonlinear relationship between temperature and biological processes means that fluctuating temperatures lead to physiological, life history, and ecological consequences for ectothermic insects that diverge from those predicted from constant temperatures. Fluctuating temperatures that remain within permissive temperature ranges generally improve performance. By contrast, those which extend to stressful temperatures may have either positive impacts, allowing repair of damage accrued during exposure to thermal extremes, or negative impacts from cumulative damage during successive exposures. We discuss the mechanisms underlying these differing effects. Fluctuating temperatures could be used to enhance or weaken insects in applied rearing programs, and any prediction of insect performance in the field-including models of climate change or population performance-must account for the effect of fluctuating temperatures.

  6. Comparing Free-Free and Shaker Table Model Correlation Methods Using Jim Beam

    NASA Technical Reports Server (NTRS)

    Ristow, James; Smith, Kenneth Wayne, Jr.; Johnson, Nathaniel; Kinney, Jackson

    2018-01-01

    Finite element model correlation as part of a spacecraft program has always been a challenge. For any NASA mission, the coupled system response of the spacecraft and launch vehicle can be determined analytically through a Coupled Loads Analysis (CLA), as it is not possible to test the spacecraft and launch vehicle coupled system before launch. The value of the CLA is highly dependent on the accuracy of the frequencies and mode shapes extracted from the spacecraft model. NASA standards require the spacecraft model used in the final Verification Loads Cycle to be correlated by either a modal test or by comparison of the model with Frequency Response Functions (FRFs) obtained during the environmental qualification test. Due to budgetary and time constraints, most programs opt to correlate the spacecraft dynamic model during the environmental qualification test, conducted on a large shaker table. For any model correlation effort, the key has always been finding a proper definition of the boundary conditions. This paper is a correlation case study to investigate the difference in responses of a simple structure using a free-free boundary, a fixed boundary on the shaker table, and a base-drive vibration test, all using identical instrumentation. The NAVCON Jim Beam test structure, featured in the IMAC round robin modal test of 2009, was selected as a simple, well recognized and well characterized structure to conduct this investigation. First, a free-free impact modal test of the Jim Beam was done as an experimental control. Second, the Jim Beam was mounted to a large 20,000 lbf shaker, and an impact modal test in this fixed configuration was conducted. Lastly, a vibration test of the Jim Beam was conducted on the shaker table. The free-free impact test, the fixed impact test, and the base-drive test were used to assess the effect of the shaker modes, evaluate the validity of fixed-base modeling assumptions, and compare final model correlation results between these

  7. Fluctuating cognition in dementia with Lewy bodies and Alzheimer's disease is qualitatively distinct

    PubMed Central

    Bradshaw, J; Saling, M; Hopwood, M; Anderson, V; Brodtmann, A

    2004-01-01

    Objectives: To document and illustrate qualitative features of fluctuating cognition as described by care givers of patients with probable dementia with Lewy bodies (DLB) and Alzheimer's disease (AD). To determine whether the quality of the fluctuations differs between DLB and AD. To examine the clinical utility of two recently developed rating scales. Methods: Care givers of 13 patients with early probable DLB and 12 patients with early probable AD were interviewed using the Clinician Assessment of Fluctuation and the One Day Fluctuation Assessment Scale, both developed recently. Descriptions of fluctuating cognition were recorded verbatim, analysed, and rated. Results: Descriptions of fluctuating cognition in DLB had a spontaneous, periodic, transient quality, which appeared to reflect an interruption in the ongoing flow of awareness or attention that impacted on functional abilities. Descriptions of fluctuations in AD frequently highlighted episodes of memory failure, or a more enduring state shift in the form of "good" and "bad" days, typically occurring in response to the cognitive demands of the immediate environment. These qualitative differences could be detected reliably by independent raters, but were not always captured in standard severity scores. Conclusion: Fluctuations occuring in DLB have particular characteristics that are distinguishable from fluctuations occurring in AD. Interpretation and application of the fluctuation criterion continues to limit the diagnostic sensitivity of the consensus criteria for DLB. Findings suggest that explicit documentation and a wider appreciation of these distinctions could improve the reliability with which less experienced clinicians identify this core diagnostic feature in the clinical setting. PMID:14966152

  8. Automatically operable self-leveling load table

    NASA Technical Reports Server (NTRS)

    Burch, J. L. (Inventor)

    1974-01-01

    A self-leveling load table is described which is automatically maintained level by selectively opening and closing solenoid valves for inserting and removing air from chambers under the table. The table is floated in a fluid by nine air chambers beneath the top of the table. These chambers are open at the bottom and four oppositely located chambers are used for leveling the table by having the air increased or decreased by means of a flexible hose. Air bearing pendulums are used for selectively energizing solenoid valves which either apply pressurized air to the chamber or evacuate air from the chamber by means of a vacuum source.

  9. Development of a Moodle Course for Schoolchildren's Table Tennis Learning Based on Competence Motivation Theory: Its Effectiveness in Comparison to Traditional Training Method

    ERIC Educational Resources Information Center

    Zou, Junhua; Liu, Qingtang; Yang, Zongkai

    2012-01-01

    Based on Competence Motivation Theory (CMT), a Moodle course for schoolchildren's table tennis learning was developed (The URL is http://www.bssepp.com, and this course allows guest access). The effects of the course on students' knowledge, perceived competence and interest were evaluated through quantitative methods. The sample of the study…

  10. Low Mach number fluctuating hydrodynamics of multispecies liquid mixtures

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

    Donev, Aleksandar, E-mail: donev@courant.nyu.edu; Bhattacharjee, Amit Kumar; Nonaka, Andy

    We develop a low Mach number formulation of the hydrodynamic equations describing transport of mass and momentum in a multispecies mixture of incompressible miscible liquids at specified temperature and pressure, which generalizes our prior work on ideal mixtures of ideal gases [Balakrishnan et al., “Fluctuating hydrodynamics of multispecies nonreactive mixtures,” Phys. Rev. E 89 013017 (2014)] and binary liquid mixtures [Donev et al., “Low mach number fluctuating hydrodynamics of diffusively mixing fluids,” Commun. Appl. Math. Comput. Sci. 9(1), 47-105 (2014)]. In this formulation, we combine and extend a number of existing descriptions of multispecies transport available in the literature. Themore » formulation applies to non-ideal mixtures of arbitrary number of species, without the need to single out a “solvent” species, and includes contributions to the diffusive mass flux due to gradients of composition, temperature, and pressure. Momentum transport and advective mass transport are handled using a low Mach number approach that eliminates fast sound waves (pressure fluctuations) from the full compressible system of equations and leads to a quasi-incompressible formulation. Thermal fluctuations are included in our fluctuating hydrodynamics description following the principles of nonequilibrium thermodynamics. We extend the semi-implicit staggered-grid finite-volume numerical method developed in our prior work on binary liquid mixtures [Nonaka et al., “Low mach number fluctuating hydrodynamics of binary liquid mixtures,” http://arxiv.org/abs/1410.2300 (2015)] and use it to study the development of giant nonequilibrium concentration fluctuations in a ternary mixture subjected to a steady concentration gradient. We also numerically study the development of diffusion-driven gravitational instabilities in a ternary mixture and compare our numerical results to recent experimental measurements [Carballido-Landeira et al., “Mixed-mode instability of

  11. Let Us Make the Table Periodic.

    ERIC Educational Resources Information Center

    Campbell, J. Arthur

    1989-01-01

    An approach to teaching the properties of the elements and their arrangement in the periodic table is suggested. Discussed are symbols for the elements, format of the table, and coding the properties of the elements on the table. (CW)

  12. The Aerodynamic Plane Table

    NASA Technical Reports Server (NTRS)

    Zahm, A F

    1924-01-01

    This report gives the description and the use of a specially designed aerodynamic plane table. For the accurate and expeditious geometrical measurement of models in an aerodynamic laboratory, and for miscellaneous truing operations, there is frequent need for a specially equipped plan table. For example, one may have to measure truly to 0.001 inch the offsets of an airfoil at many parts of its surface. Or the offsets of a strut, airship hull, or other carefully formed figure may require exact calipering. Again, a complete airplane model may have to be adjusted for correct incidence at all parts of its surfaces or verified in those parts for conformance to specifications. Such work, if but occasional, may be done on a planing or milling machine; but if frequent, justifies the provision of a special table. For this reason it was found desirable in 1918 to make the table described in this report and to equip it with such gauges and measures as the work should require.

  13. Fluctuations of a q-deformed fermion gas

    NASA Astrophysics Data System (ADS)

    Zeng, Qijun; Ge, Jing; Luo, Yongsong

    2018-05-01

    The theory of q-deformed fermions is one of the theories of q-deformed oscillators. Within the framework of this theory and the traditional fluctuation theory, we investigate fluctuations of q-deformed fermion gas and obtain the expressions of fluctuations of the internal energy U, the particle number N and the correlation of fluctuations of the two physical quantities above. Further numerical calculation reveals that fluctuations of such a system have some interesting and particular features. We consider that this work may provide much insight into the theory of q fermions, and may also be helpful for the theory of q-deformed oscillators.

  14. Evaluation of Testing Methods to Develop Test Requirements for a Workstation Table Safety Standard

    DOT National Transportation Integrated Search

    2010-10-12

    Investigations of passenger train accidents have revealed serious safety hazards associated with the thin, rigid tops of workstation tables, which are common fixtures aboard rail cars. Thoracic and abdominal injuries caused by occupant impact with wo...

  15. An Investigation of Applications for Thermodynamic Work Potential Methods: Working Tables and Charts for Estimation of Thermodynamic Work Potential in Equilibrium Mixtures of Jet-A and Air

    NASA Technical Reports Server (NTRS)

    Mavris, Dimitri; Roth, Bryce; McDonald, Rob

    2002-01-01

    The objective of this report is to provide a tool to facilitate the application of thermodynamic work potential methods to aircraft and engine analysis. This starts with a discussion of the theoretical background underlying these methods, which is then used to derive various equations useful for thermodynamic analysis of aircraft engines. The work potential analysis method is implemented in the form of a set of working charts and tables that can be used to graphically evaluate work potential stored in high-enthalpy gas. The range of validity for these tables is 300 to 36,000 R, pressures between between 0.01 atm and 100 atm, and fuel-air ratios from zero to stoichiometric. The derivations and charts assume mixtures of Jet-A and air as the working fluid. The thermodynamic properties presented in these charts were calculated based upon standard thermodynamic curve fits.

  16. A method for simulating transient ground-water recharge in deep water-table settings in central Florida by using a simple water-balance/transfer-function model

    USGS Publications Warehouse

    O'Reilly, Andrew M.

    2004-01-01

    A relatively simple method is needed that provides estimates of transient ground-water recharge in deep water-table settings that can be incorporated into other hydrologic models. Deep water-table settings are areas where the water table is below the reach of plant roots and virtually all water that is not lost to surface runoff, evaporation at land surface, or evapotranspiration in the root zone eventually becomes ground-water recharge. Areas in central Florida with a deep water table generally are high recharge areas; consequently, simulation of recharge in these areas is of particular interest to water-resource managers. Yet the complexities of meteorological variations and unsaturated flow processes make it difficult to estimate short-term recharge rates, thereby confounding calibration and predictive use of transient hydrologic models. A simple water-balance/transfer-function (WBTF) model was developed for simulating transient ground-water recharge in deep water-table settings. The WBTF model represents a one-dimensional column from the top of the vegetative canopy to the water table and consists of two components: (1) a water-balance module that simulates the water storage capacity of the vegetative canopy and root zone; and (2) a transfer-function module that simulates the traveltime of water as it percolates from the bottom of the root zone to the water table. Data requirements include two time series for the period of interest?precipitation (or precipitation minus surface runoff, if surface runoff is not negligible) and evapotranspiration?and values for five parameters that represent water storage capacity or soil-drainage characteristics. A limiting assumption of the WBTF model is that the percolation of water below the root zone is a linear process. That is, percolating water is assumed to have the same traveltime characteristics, experiencing the same delay and attenuation, as it moves through the unsaturated zone. This assumption is more accurate if

  17. Clustering header categories extracted from web tables

    NASA Astrophysics Data System (ADS)

    Nagy, George; Embley, David W.; Krishnamoorthy, Mukkai; Seth, Sharad

    2015-01-01

    Revealing related content among heterogeneous web tables is part of our long term objective of formulating queries over multiple sources of information. Two hundred HTML tables from institutional web sites are segmented and each table cell is classified according to the fundamental indexing property of row and column headers. The categories that correspond to the multi-dimensional data cube view of a table are extracted by factoring the (often multi-row/column) headers. To reveal commonalities between tables from diverse sources, the Jaccard distances between pairs of category headers (and also table titles) are computed. We show how about one third of our heterogeneous collection can be clustered into a dozen groups that exhibit table-title and header similarities that can be exploited for queries.

  18. Lookup Tables Versus Stacked Rasch Analysis in Comparing Pre- and Postintervention Adult Strabismus-20 Data

    PubMed Central

    Leske, David A.; Hatt, Sarah R.; Liebermann, Laura; Holmes, Jonathan M.

    2016-01-01

    Purpose We compare two methods of analysis for Rasch scoring pre- to postintervention data: Rasch lookup table versus de novo stacked Rasch analysis using the Adult Strabismus-20 (AS-20). Methods One hundred forty-seven subjects completed the AS-20 questionnaire prior to surgery and 6 weeks postoperatively. Subjects were classified 6 weeks postoperatively as “success,” “partial success,” or “failure” based on angle and diplopia status. Postoperative change in AS-20 scores was compared for all four AS-20 domains (self-perception, interactions, reading function, and general function) overall and by success status using two methods: (1) applying historical Rasch threshold measures from lookup tables and (2) performing a stacked de novo Rasch analysis. Change was assessed by analyzing effect size, improvement exceeding 95% limits of agreement (LOA), and score distributions. Results Effect sizes were similar for all AS-20 domains whether obtained from lookup tables or stacked analysis. Similar proportions exceeded 95% LOAs using lookup tables versus stacked analysis. Improvement in median score was observed for all AS-20 domains using lookup tables and stacked analysis (P < 0.0001 for all comparisons). Conclusions The Rasch-scored AS-20 is a responsive and valid instrument designed to measure strabismus-specific health-related quality of life. When analyzing pre- to postoperative change in AS-20 scores, Rasch lookup tables and de novo stacked Rasch analysis yield essentially the same results. Translational Relevance We describe a practical application of lookup tables, allowing the clinician or researcher to score the Rasch-calibrated AS-20 questionnaire without specialized software. PMID:26933524

  19. Validating a topographically driven model of peatland water table: Implications for understanding land cover controls on water table.

    NASA Astrophysics Data System (ADS)

    Evans, Martin; Allott, Tim; Worrall, Fred; Rowson, James; Maskill, Rachael

    2014-05-01

    Water table is arguably the dominant control on biogeochemical cycling in peatland systems. Local water tables are controlled by peat surface water balance and lateral transfer of water driven by slope can be a significant component of this balance. In particular, blanket peatlands typically have relatively high surface slope compared to other peatland types so that there is the potential for water table to be significantly contolled by topographic context. UK blanket peatlands are also significantly eroded so that there is the potential for additional topographic drainage of the peatland surface. This paper presents a topographically driven model of blanket peat water table. An initial model presented in Allott et al. (2009) has been refined and tested against further water table data collected across the Bleaklow and Kinderscout plateaux of the English Peak District. The water table model quantifies the impact of peat erosion on water table throughout this dramatically dissected landscape demonstrating that almost 50% of the landscape has suffered significant water table drawdown. The model calibrates the impact of slope and degree of dissection on local water tables but does not incorporate any effects of surface cover on water table conditions. Consequently significant outliers in the test data are potentially indicative of important impacts of surface cover on water table conditions. In the test data presented here sites associated with regular moorland burning are significant outliers. The data currently available do not allow us to draw conclusions around the impact of land cover but they indicate an important potential application of the validated model in controlling for topographic position in further testing of the impact of land cover on peatland water tables. Allott, T.E.H. & Evans, M.G., Lindsay, J.B., Agnew, C.T., Freer, J.E., Jones, A. & Parnell, M. Water tables in Peak District blanket peatlands. Moors for the Future Report No. 17. Moors for the

  20. 40 CFR Table 3 of Subpart Aaaa to... - Requirements for Validating Continuous Emission Monitoring Systems (CEMS)

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Emission Monitoring Systems (CEMS) 3 Table 3 of Subpart AAAA to Part 60 Protection of Environment... SOURCES Pt. 60, Subpt. AAAA, Table 3 Table 3 of Subpart AAAA to Part 60—Requirements for Validating... following methods in appendix A of this part to measure oxygen (or carbon dioxide) 1. Nitrogen Oxides (Class...

  1. Numerical simulation of pressure fluctuation in 1000MW Francis turbine under small opening condition

    NASA Astrophysics Data System (ADS)

    Gong, R. Z.; Wang, H. G.; Yao, Y.; Shu, L. F.; Huang, Y. J.

    2012-11-01

    In order to study the cause of abnormal vibration in large Francis turbine under small opening condition, CFD method was adopted to analyze the flow filed and pressure fluctuation. Numerical simulation was performed on the commercial CFD code Ansys FLUENT 12, using DES method. After an effective validation of the computation result, the flow behaviour of internal flow field under small opening condition is analyzed. Pressure fluctuation in different working mode is obtained by unsteady CFD simulation, and results is compared to study its change. Radial force fluctuation is also analyzed. The result shows that the unstable flow under small opening condition leads to an increase of turbine instability in reverse pump mode, and is one possible reason of the abnormal oscillation.

  2. Topographic Controls on Hillslope-Riparian Water Table Continuity in a set of Nested Catchments, Northern Rocky Mountains, Montana

    NASA Astrophysics Data System (ADS)

    Jencso, K. G.; McGlynn, B. L.; Gooseff, M. N.; Wondzell, S. M.; Bencala, K. E.; Payn, R. A.

    2007-12-01

    Understanding how hillslope and riparian water table dynamics influence catchment scale hydrologic response remains a challenge. In steep headwater catchments with shallow soils, topographic convergence and divergence (upslope accumulated area-UAA) is a hypothesized first-order control on the distribution of soil water and groundwater. To test the relationship between UAA and the longevity of hillslope-riparian-stream shallow groundwater connectivity, we quantified water table continuity based on 80+ recording wells distributed across 24 hillslope-riparian-stream cross-sections. Cross-section upstream catchment areas ranged in size from 0.41 to 17.2 km2, within the Tenderfoot Creek Experimental Forest (U.S. Forest Service), northern Rocky Mountains, Montana, USA. We quantified toe-slope UAA and the topographic index (TI = ln a/tanβ) with a Multiple-D- Infinity (area routing in multiple infinite downslope directions) flow accumulation algorithm analysis of 1, 3, 10, and 30m ALSM derived DEMs. Indices derived from the 10m DEM best characterized subsurface flow accumulation, highlighting the balance between the process of interest, topographic complexity, and optimal grid scale representation. Across the 24 transects, toe-slope UAA ranged from 600-40,000 m2, the TI ranged from 5-16, and riparian widths were between 0-60m. Patterns in shallow groundwater table fluctuations suggest hydrologic dynamics reflective of hillslope-riparian landscape setting. Specifically, correlations were observed between longevity of hillslope-riparian water table continuity and the size of the UAA (r2=0.84) and its topographic index (r2=.86). These observations highlight the temporal component of topographic-hydrologic relationships important for understanding threshold mediated hydrologic variables. We are working to quantify the characteristics and spatial distribution of hillslope-riparian sequences and their water table dynamics to temporally link runoff source areas to whole

  3. Fluctuation-enhanced electric conductivity in electrolyte solutions

    DOE PAGES

    Péraud, Jean-Philippe; Nonaka, Andrew J.; Bell, John B.; ...

    2017-09-26

    In this work, we analyze the effects of an externally applied electric field on thermal fluctuations for a binary electrolyte fluid. We show that the fluctuating Poisson–Nernst–Planck (PNP) equations for charged multispecies diffusion coupled with the fluctuating fluid momentum equation result in enhanced charge transport via a mechanism distinct from the well-known enhancement of mass transport that accompanies giant fluctuations. Although the mass and charge transport occurs by advection by thermal velocity fluctuations, it can macroscopically be represented as electrodiffusion with renormalized electric conductivity and a nonzero cation–anion diffusion coefficient. Specifically, we predict a nonzero cation–anion Maxwell– Stefan coefficient proportionalmore » to the square root of the salt concentration, a prediction that agrees quantitatively with experimental measurements. The renormalized or effective macroscopic equations are different from the starting PNP equations, which contain no cross-diffusion terms, even for rather dilute binary electrolytes. At the same time, for infinitely dilute solutions the renormalized electric conductivity and renormalized diffusion coefficients are consistent and the classical PNP equations with renormalized coefficients are recovered, demonstrating the self-consistency of the fluctuating hydrodynamics equations. Our calculations show that the fluctuating hydrodynamics approach recovers the electrophoretic and relaxation corrections obtained by Debye–Huckel–Onsager theory, while elucidating the physical origins of these corrections and generalizing straightforwardly to more complex multispecies electrolytes. Lastly, we show that strong applied electric fields result in anisotropically enhanced “giant” velocity fluctuations and reduced fluctuations of salt concentration.« less

  4. Fluctuation-enhanced electric conductivity in electrolyte solutions

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

    Péraud, Jean-Philippe; Nonaka, Andrew J.; Bell, John B.

    In this work, we analyze the effects of an externally applied electric field on thermal fluctuations for a binary electrolyte fluid. We show that the fluctuating Poisson–Nernst–Planck (PNP) equations for charged multispecies diffusion coupled with the fluctuating fluid momentum equation result in enhanced charge transport via a mechanism distinct from the well-known enhancement of mass transport that accompanies giant fluctuations. Although the mass and charge transport occurs by advection by thermal velocity fluctuations, it can macroscopically be represented as electrodiffusion with renormalized electric conductivity and a nonzero cation–anion diffusion coefficient. Specifically, we predict a nonzero cation–anion Maxwell– Stefan coefficient proportionalmore » to the square root of the salt concentration, a prediction that agrees quantitatively with experimental measurements. The renormalized or effective macroscopic equations are different from the starting PNP equations, which contain no cross-diffusion terms, even for rather dilute binary electrolytes. At the same time, for infinitely dilute solutions the renormalized electric conductivity and renormalized diffusion coefficients are consistent and the classical PNP equations with renormalized coefficients are recovered, demonstrating the self-consistency of the fluctuating hydrodynamics equations. Our calculations show that the fluctuating hydrodynamics approach recovers the electrophoretic and relaxation corrections obtained by Debye–Huckel–Onsager theory, while elucidating the physical origins of these corrections and generalizing straightforwardly to more complex multispecies electrolytes. Lastly, we show that strong applied electric fields result in anisotropically enhanced “giant” velocity fluctuations and reduced fluctuations of salt concentration.« less

  5. Fluctuation-enhanced electric conductivity in electrolyte solutions.

    PubMed

    Péraud, Jean-Philippe; Nonaka, Andrew J; Bell, John B; Donev, Aleksandar; Garcia, Alejandro L

    2017-10-10

    We analyze the effects of an externally applied electric field on thermal fluctuations for a binary electrolyte fluid. We show that the fluctuating Poisson-Nernst-Planck (PNP) equations for charged multispecies diffusion coupled with the fluctuating fluid momentum equation result in enhanced charge transport via a mechanism distinct from the well-known enhancement of mass transport that accompanies giant fluctuations. Although the mass and charge transport occurs by advection by thermal velocity fluctuations, it can macroscopically be represented as electrodiffusion with renormalized electric conductivity and a nonzero cation-anion diffusion coefficient. Specifically, we predict a nonzero cation-anion Maxwell-Stefan coefficient proportional to the square root of the salt concentration, a prediction that agrees quantitatively with experimental measurements. The renormalized or effective macroscopic equations are different from the starting PNP equations, which contain no cross-diffusion terms, even for rather dilute binary electrolytes. At the same time, for infinitely dilute solutions the renormalized electric conductivity and renormalized diffusion coefficients are consistent and the classical PNP equations with renormalized coefficients are recovered, demonstrating the self-consistency of the fluctuating hydrodynamics equations. Our calculations show that the fluctuating hydrodynamics approach recovers the electrophoretic and relaxation corrections obtained by Debye-Huckel-Onsager theory, while elucidating the physical origins of these corrections and generalizing straightforwardly to more complex multispecies electrolytes. Finally, we show that strong applied electric fields result in anisotropically enhanced "giant" velocity fluctuations and reduced fluctuations of salt concentration.

  6. Fluctuation-enhanced electric conductivity in electrolyte solutions

    PubMed Central

    Péraud, Jean-Philippe; Nonaka, Andrew J.; Bell, John B.; Donev, Aleksandar; Garcia, Alejandro L.

    2017-01-01

    We analyze the effects of an externally applied electric field on thermal fluctuations for a binary electrolyte fluid. We show that the fluctuating Poisson–Nernst–Planck (PNP) equations for charged multispecies diffusion coupled with the fluctuating fluid momentum equation result in enhanced charge transport via a mechanism distinct from the well-known enhancement of mass transport that accompanies giant fluctuations. Although the mass and charge transport occurs by advection by thermal velocity fluctuations, it can macroscopically be represented as electrodiffusion with renormalized electric conductivity and a nonzero cation–anion diffusion coefficient. Specifically, we predict a nonzero cation–anion Maxwell–Stefan coefficient proportional to the square root of the salt concentration, a prediction that agrees quantitatively with experimental measurements. The renormalized or effective macroscopic equations are different from the starting PNP equations, which contain no cross-diffusion terms, even for rather dilute binary electrolytes. At the same time, for infinitely dilute solutions the renormalized electric conductivity and renormalized diffusion coefficients are consistent and the classical PNP equations with renormalized coefficients are recovered, demonstrating the self-consistency of the fluctuating hydrodynamics equations. Our calculations show that the fluctuating hydrodynamics approach recovers the electrophoretic and relaxation corrections obtained by Debye–Huckel–Onsager theory, while elucidating the physical origins of these corrections and generalizing straightforwardly to more complex multispecies electrolytes. Finally, we show that strong applied electric fields result in anisotropically enhanced “giant” velocity fluctuations and reduced fluctuations of salt concentration. PMID:28973890

  7. Detrended fluctuation analysis made flexible to detect range of cross-correlated fluctuations

    NASA Astrophysics Data System (ADS)

    Kwapień, Jarosław; Oświecimka, Paweł; DroŻdŻ, Stanisław

    2015-11-01

    The detrended cross-correlation coefficient ρDCCA has recently been proposed to quantify the strength of cross-correlations on different temporal scales in bivariate, nonstationary time series. It is based on the detrended cross-correlation and detrended fluctuation analyses (DCCA and DFA, respectively) and can be viewed as an analog of the Pearson coefficient in the case of the fluctuation analysis. The coefficient ρDCCA works well in many practical situations but by construction its applicability is limited to detection of whether two signals are generally cross-correlated, without the possibility to obtain information on the amplitude of fluctuations that are responsible for those cross-correlations. In order to introduce some related flexibility, here we propose an extension of ρDCCA that exploits the multifractal versions of DFA and DCCA: multifractal detrended fluctuation analysis and multifractal detrended cross-correlation analysis, respectively. The resulting new coefficient ρq not only is able to quantify the strength of correlations but also allows one to identify the range of detrended fluctuation amplitudes that are correlated in two signals under study. We show how the coefficient ρq works in practical situations by applying it to stochastic time series representing processes with long memory: autoregressive and multiplicative ones. Such processes are often used to model signals recorded from complex systems and complex physical phenomena like turbulence, so we are convinced that this new measure can successfully be applied in time-series analysis. In particular, we present an example of such application to highly complex empirical data from financial markets. The present formulation can straightforwardly be extended to multivariate data in terms of the q -dependent counterpart of the correlation matrices and then to the network representation.

  8. Advances in superresolution optical fluctuation imaging (SOFI)

    PubMed Central

    Dertinger, Thomas; Pallaoro, Alessia; Braun, Gary; Ly, Sonny; Laurence, Ted A.; Weiss, Shimon

    2013-01-01

    We review the concept of superresolution optical fluctuation imaging (SOFI), discuss its attributes and trade-offs (in comparison with other superresolution methods), and present superresolved images taken on samples stained with quantum dots, organic dyes, and plasmonic metal nanoparticles. We also discuss the prospects of SOFI for live cell superresolution imaging and for imaging with other (non-fluorescent) contrasts. PMID:23672771

  9. 40 CFR Table 3 of Subpart Aaaa of... - Requirements for Validating Continuous Emission Monitoring Systems (CEMS)

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Emission Monitoring Systems (CEMS) 3 Table 3 of Subpart AAAA of Part 60 Protection of Environment... Definitions What definitions must I know? Pt. 60, Subpt. AAAA, Table 3 Table 3 of Subpart AAAA of Part 60... levels Use the following methods in appendix A of this part to measure oxygen (or carbon dioxide) 1...

  10. Air-Bearing Table for Machine Shops

    NASA Technical Reports Server (NTRS)

    Ambrisco, D.

    1986-01-01

    Frequent workpiece repositioning made easier. Air-bearing table facilitates movement of heavy workpiece during machining or between repeated operations at different positions. Table assembly consists of workpiece supporting fixture riding on air bearing. Table especially useful for inertia welding, in which ease of mobility is important.

  11. Design of a lens table for a double toroidal electron spectrometer

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

    Liu Xiaojng; Nicolas, Christophe; Miron, Catalin

    2013-03-15

    We report here on the method we developed to build a lens table for a four-element electrostatic transfer lens operated together with a double toroidal electron energy analyzer designed by one of us, and whose original design and further improvements are described in detail in Miron et al. [Rev. Sci. Instrum. 68, 3728 (1997)] and Le Guen et al. [Rev. Sci. Instrum. 73, 3885 (2002)]. Both computer simulations and laboratory instrument tuning were performed in order to build this lens table. The obtained result was tested for a broad range of electron kinetic energies and analyzer pass energies. Based onmore » this new lens table, allowing to easily computer control the spectrometer working conditions, we could routinely achieve an electron energy resolution ranging between 0.6% and 0.8% of the analyzer pass energy, while the electron count rate was also significantly improved. The establishment of such a lens table is of high importance to relieve experimentalists from the tedious laboring of the lens optimization, which was previously necessary prior to any measurement. The described method can be adapted to any type of electron/ion energy analyzer, and will thus be interesting for all experimentalists who own, or plan to build or improve their charged particle energy analyzers.« less

  12. Magnetic Fluctuations in the Martian Ionosphere

    NASA Technical Reports Server (NTRS)

    Espley, Jared

    2010-01-01

    The Martian ionosphere is influenced by both the solar wind and the regional magnetic fields present in the Martian crust. Both influences ought to cause time variable changes in the magnetic fields present in the ionosphere. I report observations of these magnetic field fluctuations in the Martian ionosphere. I use data from the Mars Global Surveyor magnetometer instrument. By using data from the aerobraking low altitude passes (approx. 200 km) I find that there are numerous fluctuations both near and far from the strong crustal sources. Using data from the 400 km altitude mapping phase (which is near the topside of the primary ionosphere), I look at the comparative strength of the fluctuations relative to the solar wind and temporal variations. I discuss which wave modes and instabilities could be contributing to these fluctuations. I also discuss the implications of these fluctuations for understanding energy transfer in the Martian system and the effects on atmospheric escape.

  13. a HARTREE-FOCK Nuclear Mass Table

    NASA Astrophysics Data System (ADS)

    Goriely, S.; Tondeur, F.; Pearson, J. M.

    2001-03-01

    We present the first complete nuclear mass table, HFBCS-1, to be based on the Hartree-Fock-BCS method. The force used, MSk7, is a 10-parameter Skyrme force, along with a 4-parameter δ-function pairing force and a 2-parameter phenomenological Wigner term. Our tabulation presents 9200 nuclei, including all those lying between the drip lines over the range Z, N≥8 and Z≤120. The root-mean-square error of our fit to the 1888 nuclei in this range for which measured masses are given in the 1995 Audi-Wapstra compilation is 0.738 MeV. In addition to the calculated masses, we show the calculated neutron- and proton-separation energies, and beta-decay energies. We also give for each nucleus in the table the calculated values for the deformation parameters and deformation energy (with axial and left-right symmetry assumed), and for the charge radius.

  14. 40 CFR Table E-2 to Subpart E of... - Spectral Energy Distribution and Permitted Tolerance for Conducting Radiative Tests

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Permitted Tolerance for Conducting Radiative Tests E Table E-2 to Subpart E of Part 53 Protection of... Reference Methods and Class I and Class II Equivalent Methods for PM2.5 or PM10â2.5 Pt. 53, Subpt. E, Table E-2 Table E-2 to Subpart E of Part 53—Spectral Energy Distribution and Permitted Tolerance for...

  15. Measurement of laser quantum frequency fluctuations using a Pound-Drever stabilization system

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

    Cheng, Y.J.; Mussche, P.L.; Siegman, A.E.

    1994-06-01

    The authors describe a method for measuring the frequency fluctuation spectrum of a laser oscillator, especially the weak noise contributions in the wings of the spectrum, and apply this method to confirm the existence of large excess quantum frequency fluctuations in a laser oscillator using an unstable optical resonator. The measurement apparatus uses the Pound-Drever technique, which employs an RF phase modulator and a Fabry-Perot cavity to produce a sensitive high-speed frequency discrimination signal. The authors show that this signal can also be used to measure the quantum noise contributions to the frequency spectrum of a laser oscillator. Experimental measurementsmore » on a miniature diode-pumped Nd:YAG laser using a stable optical cavity closely match the predictions of the usual Schawlow-Townes theory, while the frequency fluctuations in a nearly identical laser employing an unstable optical resonator are approximately 1,300 times larger. These much larger fluctuations arise in part from the larger output coupling and cavity bandwidth of the unstable cavity, but they also appear to confirm a predicted excess spontaneous emission factor (Petermann excess noise factor) of [approx]180 times arising from the nonorthogonal transverse mode properties of the unstable cavity.« less

  16. 14 CFR 26.5 - Applicability table.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Applicability table. 26.5 Section 26.5... AIRWORTHINESS AND SAFETY IMPROVEMENTS FOR TRANSPORT CATEGORY AIRPLANES General § 26.5 Applicability table. Table... Subpart B EAPAS/FTS Subpart C widespread fatigue damage Subpart D fuel tankflammability Subpart E...

  17. 14 CFR 26.5 - Applicability table.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Applicability table. 26.5 Section 26.5... AIRWORTHINESS AND SAFETY IMPROVEMENTS FOR TRANSPORT CATEGORY AIRPLANES General § 26.5 Applicability table. Table... Subpart B EAPAS/FTS Subpart C widespread fatigue damage Subpart D fuel tankflammability Subpart E...

  18. 14 CFR 26.5 - Applicability table.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Applicability table. 26.5 Section 26.5... AIRWORTHINESS AND SAFETY IMPROVEMENTS FOR TRANSPORT CATEGORY AIRPLANES General § 26.5 Applicability table. Table... Subpart B EAPAS/FTS Subpart C widespread fatigue damage Subpart D fuel tankflammability Subpart E...

  19. 40 CFR Table B-4 to Subpart B of... - Line Voltage and Room Temperature Test Conditions

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Conditions B Table B-4 to Subpart B of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Testing Performance Characteristics of Automated Methods for SO2, CO, O3, and NO2 Pt. 53, Subpt. B, Table B-4 Table B-4 to Subpart B of Part 53—Line Voltage and Room Temperature Test Conditions Test day...

  20. 40 CFR Table B-4 to Subpart B of... - Line Voltage and Room Temperature Test Conditions

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Conditions B Table B-4 to Subpart B of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Testing Performance Characteristics of Automated Methods for SO2, CO, O3, and NO2 Pt. 53, Subpt. B, Table B-4 Table B-4 to Subpart B of Part 53—Line Voltage and Room Temperature Test Conditions Test day...

  1. 40 CFR Table B-4 to Subpart B of... - Line Voltage and Room Temperature Test Conditions

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Conditions B Table B-4 to Subpart B of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Testing Performance Characteristics of Automated Methods for SO2, CO, O3, and NO2 Pt. 53, Subpt. B, Table B-4 Table B-4 to Subpart B of Part 53—Line Voltage and Room Temperature Test Conditions Test day...

  2. The Living Periodic Table

    ERIC Educational Resources Information Center

    Nahlik, Mary Schrodt

    2005-01-01

    To help make the abstract world of chemistry more concrete eighth-grade students, the author has them create a living periodic table that can be displayed in the classroom or hallway. This display includes information about the elements arranged in the traditional periodic table format, but also includes visual real-world representations of the…

  3. [Sterilization effect analysis of B-class pulsation table top vacuum sterilizer to dental handpieces].

    PubMed

    Zeng, Shu-Rong; Jiang, Bo; Xiao, Xiao-Rong

    2007-06-01

    Discuss sterilization effect of B-class pulsation table top vacuum pressure steam sterilizer for dental handpiece. Analysis selection of sterilizer for dental handpiece and sterilization management processes and sterilization effect monitoring, evaluation of monitoring result and effective sterilization method. The B-class pulsation table top vacuum pressure steam sterilizer to dental handpiece in West China Stomatological Hospital of Sichuan University met the requirement of the chemical and biological monitoring. Its efficiency of sterilization was 100%. The results of aerobic culture, anaerobic culture, B-type hepatitis mark monitoring to sterilized dental handpiece were negative. It is effective method for dental handpiece sterilization to use B-class pulsation table top vacuum pressure steam sterilizer.

  4. Comparison of Oregon state highway division Table-1 and Table-2 asphalt : final report.

    DOT National Transportation Integrated Search

    1991-12-01

    The objective of this study was to compare the effect of using the Oregon State Highway Division (OSHD) modified Table-1 asphalts and the OSHD modified Table-2 asphalts in asphalt concrete; the primary factors for comparison were reflective and therm...

  5. Output power fluctuations due to different weights of macro particles used in particle-in-cell simulations of Cerenkov devices

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

    Bao, Rong; Li, Yongdong; Liu, Chunliang

    2016-07-15

    The output power fluctuations caused by weights of macro particles used in particle-in-cell (PIC) simulations of a backward wave oscillator and a travelling wave tube are statistically analyzed. It is found that the velocities of electrons passed a specific slow-wave structure form a specific electron velocity distribution. The electron velocity distribution obtained in PIC simulation with a relative small weight of macro particles is considered as an initial distribution. By analyzing this initial distribution with a statistical method, the estimations of the output power fluctuations caused by different weights of macro particles are obtained. The statistical method is verified bymore » comparing the estimations with the simulation results. The fluctuations become stronger with increasing weight of macro particles, which can also be determined reversely from estimations of the output power fluctuations. With the weights of macro particles optimized by the statistical method, the output power fluctuations in PIC simulations are relatively small and acceptable.« less

  6. Daily Fluctuation in Negative Affect for Family Caregivers of Individuals With Dementia

    PubMed Central

    Liu, Yin; Kim, Kyungmin; Almeida, David M.; Zarit, Steven H.

    2017-01-01

    Objective The study examined associations of intrinsic fluctuation in daily negative affect (i.e., depression and anger) with adult day service (ADS) use, daily experiences, and other caregiving characteristics. Methods This was an 8-day diary of 173 family caregivers of individuals with dementia. Multilevel models with common within-person variance were fit first to show average associations between daily stressors and mean level of daily affect. Then multilevel models with heterogeneous within-person variance were fit to test the hypotheses on associations between ADS use, daily experiences, and intrinsic fluctuation in daily affect. Results The study showed that, when the sum of ADS days was greater than average, there was a stabilizing effect of ADS use on caregivers’ within-person fluctuation in negative affect. Moreover, fewer daily stressors and greater-than-average daily care-related stressors, more positive events, not being a spouse, greater-than-average duration of caregiving, and less-than-average dependency of individuals with dementia on activities of daily living were associated with less fluctuation. Better sleep quality was associated with less intrinsic fluctuation in anger; and younger age and more years of education were associated with less intrinsic fluctuation in daily depression. Conclusions Because emotional stability has been argued as an aspect of emotional well-being in the general populations, intrinsic fluctuation of emotional experience was suggested as an outcome of evidence-based interventions for family caregivers. PMID:25365414

  7. Water Table Depth and Growth of Young Cottonwood

    Treesearch

    W. M. Broadfoot

    1973-01-01

    Planted cottonwood grew best when the water table was about 2 feet deep, whether the tree was planted on soil with a high water table or the water table was raised 1 year after planting. Growth over a 1- foot-deep water table was about the same as over no water table, but a surface water table restricted growth of cuttings planted in the water, and killed trees planted...

  8. Round-the-table teaching: a novel approach to resuscitation education

    PubMed Central

    McGarvey, Kathryn; Scott, Karen; O'Leary, Fenton

    2014-01-01

    Background Effective cardiopulmonary resuscitation saves lives. Health professionals who care for acutely unwell children need to be prepared to care for a child in arrest. Hospitals must ensure that their staff have the knowledge, confidence and ability to respond to a child in cardiac arrest. RESUS4KIDS is a programme designed to teach paediatric resuscitation to health care professionals who care for acutely unwell children. The programme is delivered in two components: an e–learning component for pre-learning, followed by a short, practical, face-to-face course that is taught using the round-the-table teaching approach. Context Round-the-table teaching is a novel, evidence-based small group teaching approach designed to teach paediatric resuscitation skills and knowledge. Round-the-table teaching uses a structured approach to managing a collapsed child, and ensures that each participant has the opportunity to practise the essential resuscitation skills of airway manoeuvres, bag mask ventilation and cardiac compressions. Innovation Round-the-table teaching is an engaging, non-threatening approach to delivering interdisciplinary paediatric resuscitation education. The methodology ensures that all participants have the opportunity to practise each of the different essential skills associated with the Danger, Response, Send for help, Airway, Breathing, Circulation, Defibrillation or rhythm recognition (DRSABCD) approach to the collapsed child. Implications Round-the-table teaching is based on evidence-based small group teaching methods. The methodology of round-the-table teaching can be applied to any topic where participants must demonstrate an understanding of a sequential approach to a clinical skill. Round-the-table teaching uses a structured approach to managing a collapsed child PMID:25212931

  9. Online tables of contents for books: effect on usage.

    PubMed

    Morris, R C

    2001-01-01

    To explore whether the presence of online tables of contents (TOC) in an online catalog affects circulation (checkouts and inhouse usage). Two major questions were posed: (1) did the presence of online tables of contents for books increase use, and, (2) if it did, what factors might cause the increase? A randomized and stratified design was used in tracking usage of 3,957 book titles that were previously divided into two groups: one with TOC and one without TOC. Stratification was done for year of imprint, location, subject, previous use, circulating or non-circulating status, and presence of TOC. The use was tracked by the online catalog statistics in the InnoPac online catalog for fourteen months. The study found that tables of contents do increase usage. It also showed a correlation in the size of the effect based on the currency of the titles. In general, even after adjusting for all of the variables (publication date, location, circulation status, subject, and previous use), the odds of a title being used increased by 45% if the titles had online tables of contents, a statistically significant impact at the 0.05 level. This case-control study presents new information about the impact on circulation and inhouse use when tables of contents for books are added to the online catalog record. The study helps to establish the positive role of tables of contents in online catalogs. The research establishes TOC as a major parameter that can be successfully studied using quantitative methods. The study also provides information professionals with some guidance on when enhancement of TOC is likely to be most effective in increasing the use of existing collections.

  10. An uncovered risk factor of sonothrombolysis: Substantial fluctuation of ultrasound transmittance through the human skull.

    PubMed

    Wang, Zuojun; Komatsu, Teppei; Mitsumura, Hidetaka; Nakata, Norio; Ogawa, Takeki; Iguchi, Yasuyuki; Yokoyama, Masayuki

    2017-05-01

    Sonothrombolysis is one of the most feasible methods for enhancing clot lysis with a recombinant tissue plasminogen activator (rt-PA) in cases of acute ischemic strokes. For safe and efficient clinical practices of sonothrombolysis, accurate estimation of ultrasound transmittance through the human skull is critical. Previously, we reported substantial and periodic fluctuation of ultrasound transmittance through a bone-phantom plate following changes to ultrasound frequency, the thickness of the bone-phantom plate, and the distance between a transducer and the bone-phantom plate. In the present study, we clarify the transmittance behavior of medium-frequency ultrasound (from 400kHz to 600kHz) through the human skull, and examine reduction of the transmittance fluctuation. For the study, we measured transmittance of sinusoidal ultrasound waves at 400kHz, 500kHz, and 600kHz at 13 temple spots on 3 human skulls by changing the distance between a transducer and the skull bone, and found substantial and periodic fluctuation in the transmittance behaviors for these sinusoidal voltage excitations. Degrees of the fluctuation varied depending on the measurement spots. A fluctuation ratio between the maximum transmittance and the minimum transmittance reached 3 in some spots. This large transmittance fluctuation is considered to be a risk factor for sonothrombolysis therapies. We examined a modulated ultrasound wave to reduce the fluctuation, and succeeded in obtaining considerable reduction. The average fluctuation ratios for 400-kHz, 500-kHz, and 600-kHz waves were 2.38, 2.38, and 2.07, respectively. We successfully reduced the ratio to 1.72 by using a periodic selection of random frequency (PSRF)-type of modulation wave. The thus obtained results indicate that attention to the fluctuation in ultrasound transmittance through the skull is necessary for safe and effective sonothrombolysis therapies, and that modulated ultrasound waves constitute a powerful method for reducing

  11. Fluctuating Hydrodynamics Confronts the Rapidity Dependence of Transverse Momentum Fluctuations

    NASA Astrophysics Data System (ADS)

    Pokharel, Rajendra; Gavin, Sean; Moschelli, George

    2012-10-01

    Interest in the development of the theory of fluctuating hydrodynamics is growing [1]. Early efforts suggested that viscous diffusion broadens the rapidity dependence of transverse momentum correlations [2]. That work stimulated an experimental analysis by STAR [3]. We attack this new data along two fronts. First, we compute STAR's fluctuation observable using the NeXSPheRIO code, which combines fluctuating initial conditions from a string fragmentation model with deterministic viscosity-free hydrodynamic evolution. We find that NeXSPheRIO produces a longitudinal narrowing, in contrast to the data. Second, we study the hydrodynamic evolution using second order causal viscous hydrodynamics including Langevin noise. We obtain a deterministic evolution equation for the transverse momentum density correlation function. We use the latest theoretical equations of state and transport coefficients to compute STAR's observable. The results are in excellent accord with the measured broadening. In addition, we predict features of the distribution that can distinguish 2nd and 1st order diffusion. [4pt] [1] J. Kapusta, B. Mueller, M. Stephanov, arXiv:1112.6405 [nucl-th].[0pt] [2] S. Gavin and M. Abdel-Aziz, Phys. Rev. Lett. 97, 162302 (2006)[0pt] [3] H. Agakishiev et al., STAR, STAR, Phys. Lett. B704

  12. Influence of Dynamic Hydraulic Conditions on Nitrogen Cycling in Column Experiments

    NASA Astrophysics Data System (ADS)

    Gassen, Niklas; von Netzer, Frederick; Ryabenko, Evgenia; Lüders, Tillmann; Stumpp, Christine

    2015-04-01

    In order to improve management strategies of agricultural nitrogen input, it is of major importance to further understand which factors influence turnover processes within the nitrogen cycle. Many studies have focused on the fate of nitrate in hydrological systems, but up to date only little is known about the influence of dynamic hydraulic conditions on the fate of nitrate at the soil-groundwater interface. We conducted column experiments with natural sediment and compared a system with a fluctuating water table to systems with different water content and static conditions under the constant input of ammonia into the system. We used hydrochemical methods in order to trace nitrogen species, 15N isotope methods to get information about dominating turnover processes and microbial community analysis in order to connect hydrochemical and microbial information. We found that added ammonia was removed more effectively under dynamic hydraulic conditions than under static conditions. Furthermore, denitrification is the dominant process under saturated, static conditions, while nitrification is more important under unsaturated, static conditions. We conclude that a fluctuating water table creates hot spots where both nitrification and denitrification processes can occur spatially close to each other and therefore remove nitrogen more effectively from the system. Furthermore, the fluctuating water table enhances the exchange of solutes and triggers hot moments of solute turnover. Therefore we conclude that a fluctuating water table can amplify hot spots and trigger hot moments of nitrogen cycling.

  13. A VLSI architecture for performing finite field arithmetic with reduced table look-up

    NASA Technical Reports Server (NTRS)

    Hsu, I. S.; Truong, T. K.; Reed, I. S.

    1986-01-01

    A new table look-up method for finding the log and antilog of finite field elements has been developed by N. Glover. In his method, the log and antilog of a field element is found by the use of several smaller tables. The method is based on a use of the Chinese Remainder Theorem. The technique often results in a significant reduction in the memory requirements of the problem. A VLSI architecture is developed for a special case of this new algorithm to perform finite field arithmetic including multiplication, division, and the finding of an inverse element in the finite field.

  14. 40 CFR Appendix - Tables to Part 132

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 23 2013-07-01 2013-07-01 false Tables to Part 132 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY GUIDANCE FOR THE GREAT LAKES SYSTEM Application of part 132 requirements in Great Lakes States and Tribes. Pt. 132, Tables Tables to Part 132 Table 1—Acute Water Quality...

  15. Nonequilibrium fluctuations during diffusion in liquid layers

    NASA Astrophysics Data System (ADS)

    Brogioli, Doriano; Vailati, Alberto

    2017-07-01

    Theoretical analysis and experiments have provided compelling evidence of the presence of long-range nonequilibrium concentration fluctuations during diffusion processes in fluids. In this paper, we investigate the dependence of the features of the fluctuations from the dimensionality of the system. In three-dimensional fluids the amplitude of nonequilibrium fluctuations can become several orders of magnitude larger than that of equilibrium fluctuations. Notwithstanding that, the amplitude of nonequilibrium fluctuations remains small with respect to the concentration difference driving the diffusion process. By extending the theory to two-dimensional systems, such as liquid monolayers and bilayers, we show that the amplitude of the fluctuations becomes much stronger than in three-dimensional systems. We investigate the properties of the fronts of diffusion and show that they have a self-affine structure characterized by a Hurst exponent H =1 . We discuss the implications of these results for diffusion in liquid crystals and in cellular membranes of living organisms.

  16. Nonequilibrium fluctuations during diffusion in liquid layers.

    PubMed

    Brogioli, Doriano; Vailati, Alberto

    2017-07-01

    Theoretical analysis and experiments have provided compelling evidence of the presence of long-range nonequilibrium concentration fluctuations during diffusion processes in fluids. In this paper, we investigate the dependence of the features of the fluctuations from the dimensionality of the system. In three-dimensional fluids the amplitude of nonequilibrium fluctuations can become several orders of magnitude larger than that of equilibrium fluctuations. Notwithstanding that, the amplitude of nonequilibrium fluctuations remains small with respect to the concentration difference driving the diffusion process. By extending the theory to two-dimensional systems, such as liquid monolayers and bilayers, we show that the amplitude of the fluctuations becomes much stronger than in three-dimensional systems. We investigate the properties of the fronts of diffusion and show that they have a self-affine structure characterized by a Hurst exponent H=1. We discuss the implications of these results for diffusion in liquid crystals and in cellular membranes of living organisms.

  17. 44 CFR 208.12 - Maximum Pay Rate Table.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Maximum Pay Rate Table. 208... § 208.12 Maximum Pay Rate Table. (a) Purpose. This section establishes the process for creating and updating the Maximum Pay Rate Table (Table), and the Table's use to reimburse Affiliated Personnel (Task...

  18. Fluctuation theorem: A critical review

    NASA Astrophysics Data System (ADS)

    Malek Mansour, M.; Baras, F.

    2017-10-01

    Fluctuation theorem for entropy production is revisited in the framework of stochastic processes. The applicability of the fluctuation theorem to physico-chemical systems and the resulting stochastic thermodynamics were analyzed. Some unexpected limitations are highlighted in the context of jump Markov processes. We have shown that these limitations handicap the ability of the resulting stochastic thermodynamics to correctly describe the state of non-equilibrium systems in terms of the thermodynamic properties of individual processes therein. Finally, we considered the case of diffusion processes and proved that the fluctuation theorem for entropy production becomes irrelevant at the stationary state in the case of one variable systems.

  19. Wall-pressure fluctuations beneath a spatially evolving turbulent boundary layer

    NASA Astrophysics Data System (ADS)

    Mahesh, Krishnan; Kumar, Praveen

    2016-11-01

    Wall-pressure fluctuations beneath a turbulent boundary layer are important in applications dealing with structural deformation and acoustics. Simulations are performed for flat plate and axisymmetric, spatially evolving zero-pressure-gradient turbulent boundary layers at inflow Reynolds number of 1400 and 2200 based on momentum thickness. The simulations generate their own inflow using the recycle-rescale method. The results for mean velocity and second-order statistics show excellent agreement with the data available in literature. The spectral characteristics of wall-pressure fluctuations and their relation to flow structure will be discussed. This work is supported by ONR.

  20. Spin-density fluctuations and the fluctuation-dissipation theorem in 3 d ferromagnetic metals

    DOE PAGES

    Wysocki, Alex L.; Valmispild, V. N.; Kutepov, A.; ...

    2017-11-15

    Spatial and time scales of spin-density fluctuations (SDFs) were analyzed in 3d ferromagnets using ab initio linear-response calculations of complete wave-vector and energy dependence of the dynamic spin susceptibility tensor. We demonstrate that SDFs are spread continuously over the entire Brillouin zone and while the majority of them reside within the 3d bandwidth, a significant amount comes from much higher energies. A validity of the adiabatic approximation in spin dynamics is discussed. The SDF spectrum is shown to have two main constituents: a minor low-energy spin-wave contribution and a much larger high-energy component from more localized excitations. Furthermore, using themore » fluctuation-dissipation theorem, the on-site spin correlator and the related effective fluctuating moment were properly evaluated and their universal dependence on the 3d band population is further discussed.« less

  1. Spin-density fluctuations and the fluctuation-dissipation theorem in 3 d ferromagnetic metals

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

    Wysocki, Alex L.; Valmispild, V. N.; Kutepov, A.

    Spatial and time scales of spin-density fluctuations (SDFs) were analyzed in 3d ferromagnets using ab initio linear-response calculations of complete wave-vector and energy dependence of the dynamic spin susceptibility tensor. We demonstrate that SDFs are spread continuously over the entire Brillouin zone and while the majority of them reside within the 3d bandwidth, a significant amount comes from much higher energies. A validity of the adiabatic approximation in spin dynamics is discussed. The SDF spectrum is shown to have two main constituents: a minor low-energy spin-wave contribution and a much larger high-energy component from more localized excitations. Furthermore, using themore » fluctuation-dissipation theorem, the on-site spin correlator and the related effective fluctuating moment were properly evaluated and their universal dependence on the 3d band population is further discussed.« less

  2. 26 CFR 1.6655-0 - Table of contents.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES Additions to the Tax, Additional Amounts, and Assessable Penalties § 1.6655-0 Table of... month. (3) Application of the rules related to the annualized income installment method to the adjusted...

  3. Quantifying two-dimensional nonstationary signal with power-law correlations by detrended fluctuation analysis

    NASA Astrophysics Data System (ADS)

    Fan, Qingju; Wu, Yonghong

    2015-08-01

    In this paper, we develop a new method for the multifractal characterization of two-dimensional nonstationary signal, which is based on the detrended fluctuation analysis (DFA). By applying to two artificially generated signals of two-component ARFIMA process and binomial multifractal model, we show that the new method can reliably determine the multifractal scaling behavior of two-dimensional signal. We also illustrate the applications of this method in finance and physiology. The analyzing results exhibit that the two-dimensional signals under investigation are power-law correlations, and the electricity market consists of electricity price and trading volume is multifractal, while the two-dimensional EEG signal in sleep recorded for a single patient is weak multifractal. The new method based on the detrended fluctuation analysis may add diagnostic power to existing statistical methods.

  4. The Influence of Training Strategy and Physical Condition toward Forehand Drive Ability in Table Tennis

    NASA Astrophysics Data System (ADS)

    Langitan, F. W.

    2018-02-01

    The objective of this research is to find out the influence of training strategy and physical condition toward forehand drive ability in table tennis of student in faculty of sport in university of Manado, department of health and recreation education. The method used in this research was factorial 2x2 design method. The population was taken from the student of Faculty of Sport at Manado State University, Indonesia, in 2017 of 76 students for sample research. The result of this research shows that: In general, this training strategy of wall bounce gives better influence toward forehand drive ability compare with the strategy of pair training in table tennis. For the students who have strong forehand muscle, the wall bounce training strategy give better influence to their ability of forehand drive in table tennis. For the student who have weak forehand muscle, pair training strategy give better influence than wall bound training toward forehand drive ability in table tennis. There is an interaction between training using hand muscle strength to the training result in table tennis using forehand drive.

  5. Fluctuation Analysis of Redox Potential to Distinguish Microbial Fe(II) Oxidation.

    PubMed

    Enright, A M L; Ferris, F G

    2016-11-01

    We developed a novel method for distinguishing abiotic and biological iron oxidation in liquid media using oxidation-reduction (redox) potential time series data. The instrument and processing algorithm were tested by immersing the tip of a Pt electrode with an Ag-AgCl reference electrode into an active iron-oxidizing biofilm in a groundwater discharge zone, as well as in two abiotic systems: a killed sample and a chemical control from the same site. We used detrended fluctuation analysis to characterize average root mean square fluctuation behavior, which was distinct in the live system. The calculated α value scaling exponents determined by detrended fluctuation analysis were significantly different at p < 0.001. This indicates that time series of electrode response data may be used to distinguish live and abiotic chemical reaction pathways. Due to the simplicity, portability, and small size, it may be suitable for characterization of extraterrestrial environments where water has been observed, such as Mars and Europa. Key Words: Oxidation-reduction potential-Detrended fluctuation analysis-Iron-oxidizing bacteria. Astrobiology 16, 846-852.

  6. Evaluation of bed load transport subject to high shear stress fluctuations

    NASA Astrophysics Data System (ADS)

    Cheng, Nian-Sheng; Tang, Hongwu; Zhu, Lijun

    2004-05-01

    Many formulas available in the literature for computing sediment transport rates are often expressed in terms of time mean variables such as time mean bed shear stress or flow velocity, while effects of turbulence intensity, e.g., bed shear stress fluctuation, on sediment transport were seldom considered. This may be due to the fact that turbulence fluctuation is relatively limited in laboratory open-channel flows, which are often used for conducting sediment transport experiments. However, turbulence intensity could be markedly enhanced in practice. This note presents an analytical method to compute bed load transport by including effects of fluctuations in the bed shear stress. The analytical results obtained show that the transport rate enhanced by turbulence can be expressed as a simple function of the relative fluctuation of the bed shear stress. The results are also verified using data that were collected recently from specifically designed laboratory experiments. The present analysis is applicable largely for the condition of a flat bed that is comprised of uniform sand particles subject to unidirectional flows.

  7. 40 CFR Table 25 to Subpart Uuu of... - Requirements for Performance Tests for Inorganic HAP Emissions From Catalytic Reforming Units

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Inorganic HAP Emissions From Catalytic Reforming Units 25 Table 25 to Subpart UUU of Part 63 Protection of... Sulfur Recovery Units Pt. 63, Subpt. UUU, Table 25 Table 25 to Subpart UUU of Part 63—Requirements for... Procedure) in appendix A to subpart UUU; or EPA Method 5050 combined either with EPA Method 9056, or with...

  8. 40 CFR Table 25 to Subpart Uuu of... - Requirements for Performance Tests for Inorganic HAP Emissions From Catalytic Reforming Units

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Inorganic HAP Emissions From Catalytic Reforming Units 25 Table 25 to Subpart UUU of Part 63 Protection of... Sulfur Recovery Units Pt. 63, Subpt. UUU, Table 25 Table 25 to Subpart UUU of Part 63—Requirements for... Procedure) in appendix A to subpart UUU; or EPA Method 5050 combined either with EPA Method 9056, or with...

  9. 40 CFR Table 25 to Subpart Uuu of... - Requirements for Performance Tests for Inorganic HAP Emissions From Catalytic Reforming Units

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Inorganic HAP Emissions From Catalytic Reforming Units 25 Table 25 to Subpart UUU of Part 63 Protection of... Units Pt. 63, Subpt. UUU, Table 25 Table 25 to Subpart UUU of Part 63—Requirements for Performance Tests... Procedure) in appendix A to subpart UUU; or EPA Method 5050 combined either with EPA Method 9056, or with...

  10. 40 CFR Table 25 to Subpart Uuu of... - Requirements for Performance Tests for Inorganic HAP Emissions From Catalytic Reforming Units

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Inorganic HAP Emissions From Catalytic Reforming Units 25 Table 25 to Subpart UUU of Part 63 Protection of... Sulfur Recovery Units Pt. 63, Subpt. UUU, Table 25 Table 25 to Subpart UUU of Part 63—Requirements for... Procedure) in appendix A to subpart UUU; or EPA Method 5050 combined either with EPA Method 9056, or with...

  11. A multi-method study of regional groundwater circulation in the Ordos Plateau, NW China

    NASA Astrophysics Data System (ADS)

    Jiang, Xiao-Wei; Wan, Li; Wang, Xu-Sheng; Wang, Dan; Wang, Heng; Wang, Jun-Zhi; Zhang, Hong; Zhang, Zhi-Yuan; Zhao, Ke-Yu

    2018-01-01

    The Ordos Basin is one of the most intensively studied groundwater basins in China. The Ordos Plateau, located in the north part of the Ordos Basin, is ideal to study the pattern of regional groundwater circulation induced by water-table undulations due to the wavy topography and the relatively simple aquifer systems with macroscopically homogeneous sandstone. In catchments located near the first-order divide, the water table is found to be a subdued replica of the topography, and the nonclosed water-table contours in topographic highs of a catchment are indicative of regional groundwater outflow to other catchments. In topographic lows, groundwater-fed lakes/rivers, topography-driven flowing wells, water-loving and/or salt-tolerant vegetation, and soap holes are all indicative of discharge areas. In discharge areas, although groundwater inflow from recharge areas is relatively stable, seasonal variations in groundwater recharge and evapotranspiration lead to significant seasonal fluctuations in the water table, which can be used to estimate groundwater inflow and evapotranspiration rates based on water balance at different stages of water-table change. In the lowest reaches of a complex basin, superposition of local flow systems on regional flow systems has been identified based on groundwater samples collected from wells with different depths and geophysical measurements of apparent resistivity, both of which can be used for characterizing groundwater flow systems. This study enhances understanding of the pattern of regional groundwater circulation in the Ordos Plateau, and also tests the effectiveness of methods for groundwater flow-system characterization.

  12. 40 CFR 230.24 - Normal water fluctuations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Normal water fluctuations. 230.24... Impacts on Physical and Chemical Characteristics of the Aquatic Ecosystem § 230.24 Normal water fluctuations. (a) Normal water fluctuations in a natural aquatic system consist of daily, seasonal, and annual...

  13. 40 CFR 230.24 - Normal water fluctuations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Normal water fluctuations. 230.24... Impacts on Physical and Chemical Characteristics of the Aquatic Ecosystem § 230.24 Normal water fluctuations. (a) Normal water fluctuations in a natural aquatic system consist of daily, seasonal, and annual...

  14. Estimating Transmissivity from the Water Level Fluctuations of a Sinusoidally Forced Well

    USGS Publications Warehouse

    Mehnert, E.; Valocchi, A.J.; Heidari, M.; Kapoor, S.G.; Kumar, P.

    1999-01-01

    The water levels in wells are known to fluctuate in response to earth tides and changes in atmospheric pressure. These water level fluctuations can be analyzed to estimate transmissivity (T). A new method to estimate transmissivity, which assumes that the atmospheric pressure varies in a sinusoidal fashion, is presented. Data analysis for this simplified method involves using a set of type curves and estimating the ratio of the amplitudes of the well response over the atmospheric pressure. Type curves for this new method were generated based on a model for ground water flow between the well and aquifer developed by Cooper et al. (1965). Data analysis with this method confirmed these published results: (1) the amplitude ratio is a function of transmissivity, the well radius, and the frequency of the sinusoidal oscillation; and (2) the amplitude ratio is a weak function of storativity. Compared to other methods, the developed method involves simpler, more intuitive data analysis and allows shorter data sets to be analyzed. The effect of noise on estimating the amplitude ratio was evaluated and found to be more significant at lower T. For aquifers with low T, noise was shown to mask the water level fluctuations induced by atmospheric pressure changes. In addition, reducing the length of the data series did not affect the estimate of T, but the variance of the estimate was higher for the shorter series of noisy data.

  15. Scale-invariant fluctuations from Galilean genesis

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

    Wang, Yi; Brandenberger, Robert, E-mail: wangyi@physics.mcgill.ca, E-mail: rhb@physics.mcgill.ca

    2012-10-01

    We study the spectrum of cosmological fluctuations in scenarios such as Galilean Genesis \\cite(Nicolis) in which a spectator scalar field acquires a scale-invariant spectrum of perturbations during an early phase which asymptotes in the far past to Minkowski space-time. In the case of minimal coupling to gravity and standard scalar field Lagrangian, the induced curvature fluctuations depend quadratically on the spectator field and are hence non-scale-invariant and highly non-Gaussian. We show that if higher dimensional operators (the same operators that lead to the η-problem for inflation) are considered, a linear coupling between background and spectator field fluctuations is induced whichmore » leads to scale-invariant and Gaussian curvature fluctuations.« less

  16. Extracellular signal fluctuations in shark electrosensors

    NASA Astrophysics Data System (ADS)

    Brown, Brandon R.; Hughes, Mary E.; Hutchison, John C.

    2003-05-01

    We examine the roll of an extracellular gel in the functioning of the electrosensors of elasmobranchs (sharks, skates, and rays). Here we focus on physical characteristics of the gel and their mechanistic relevance to the observed functioning of the electrosensors. The electrosensitive organs show sharp transient responses to both tiny electrical fluctuations and temperature fluctuations. We present a thermoelectric characterization of the gel. The data suggest a gel-mediated mechanism of transducing thermal fluctuations to electrical fluctuations in the electrosensor, independent of the sensing cells. We also present frequency-dependent electrical properties of the gel collected using electrical impedance spectroscopy. From these measurements we try to extract characteristic relaxation times. We analyze these results within the context of the electrosensors" bandwidth, as demonstrated in previous behavioral experiments.

  17. Optical probe with light fluctuation protection

    DOEpatents

    Da Silva, Luiz B.; Chase, Charles L.

    2003-11-11

    An optical probe for tissue identification includes an elongated body. Optical fibers are located within the elongated body for transmitting light to and from the tissue. Light fluctuation protection is associated with the optical fibers. In one embodiment the light fluctuation protection includes a reflective coating on the optical fibers to reduce stray light. In another embodiment the light fluctuation protection includes a filler with very high absorption located within the elongated body between the optical fibers.

  18. EAS fluctuation approach to primary mass composition investigation

    NASA Technical Reports Server (NTRS)

    Stamenov, J. N.; Janminchev, V. D.

    1985-01-01

    The analysis of muon and electron fluctuation distribution shapes by statistical method of invers problem solution gives the possibility to obtain the relative contribution values of the five main primary nuclei groups. The method is model-independent for a big class of interaction models and can give good results for observation levels not too far from the development maximum and for the selection of showers with fixed sizes and zenith angles not bigger than 30 deg.

  19. Scaling Behavior in Mitochondrial Redox Fluctuations

    PubMed Central

    Ramanujan, V. Krishnan; Biener, Gabriel; Herman, Brian A.

    2006-01-01

    Scale-invariant long-range correlations have been reported in fluctuations of time-series signals originating from diverse processes such as heart beat dynamics, earthquakes, and stock market data. The common denominator of these apparently different processes is a highly nonlinear dynamics with competing forces and distinct feedback species. We report for the first time an experimental evidence for scaling behavior in NAD(P)H signal fluctuations in isolated mitochondria and intact cells isolated from the liver of a young (5-month-old) mouse. Time-series data were collected by two-photon imaging of mitochondrial NAD(P)H fluorescence and signal fluctuations were quantitatively analyzed for statistical correlations by detrended fluctuation analysis and spectral power analysis. Redox [NAD(P)H / NAD(P)+] fluctuations in isolated mitochondria and intact liver cells were found to display nonrandom, long-range correlations. These correlations are interpreted as arising due to the regulatory dynamics operative in Krebs' cycle enzyme network and electron transport chain in the mitochondria. This finding may provide a novel basis for understanding similar regulatory networks that govern the nonequilibrium properties of living cells. PMID:16565066

  20. Fluctuation dynamics in reconnecting current sheets

    NASA Astrophysics Data System (ADS)

    von Stechow, Adrian; Grulke, Olaf; Ji, Hantao; Yamada, Masaaki; Klinger, Thomas

    2015-11-01

    During magnetic reconnection, a highly localized current sheet forms at the boundary between opposed magnetic fields. Its steep perpendicular gradients and fast parallel drifts can give rise to a range of instabilities which can contribute to the overall reconnection dynamics. In two complementary laboratory reconnection experiments, MRX (PPPL, Princeton) and VINETA.II (IPP, Greifswald, Germany), magnetic fluctuations are observed within the current sheet. Despite the large differences in geometries (toroidal vs. linear), plasma parameters (high vs. low beta) and magnetic configuration (low vs. high magnetic guide field), similar broadband fluctuation characteristics are observed in both experiments. These are identified as Whistler-like fluctuations in the lower hybrid frequency range that propagate along the current sheet in the electron drift direction. They are intrinsic to the localized current sheet and largely independent of the slower reconnection dynamics. This contribution characterizes these magnetic fluctuations within the wide parameter range accessible by both experiments. Specifically, the fluctuation spectra and wave dispersion are characterized with respect to the magnetic topology and plasma parameters of the reconnecting current sheet.

  1. Comparison of various multifractal approaches to analyze the intermittent magnetic fluctuations observed in the Earth's magnetospheric cusp

    NASA Astrophysics Data System (ADS)

    Lamy, Hervé; Echim, Marius; Chang, Tom

    2014-05-01

    Several approaches exist to compute the multifractal characteristics of an intermittent set of fluctuations. First, the classical method based on the computation of the partition function uses the full set of fluctuations . Since it is dominated by the more numerous fluctuations of small amplitudes, this method can mask the fractal characteristics of minor fluctuations of much larger amplitude. To solve this issue, a new method was developed by Chang & Wu (2008) : the Rank-Ordered Multifractal Analysis (ROMA) The ROMA method offers a natural connection between the one-parameter monofractal scaling idea and the multifractal phenomenon of intermittency. The key-element in ROMA is to find s(Y), the spectrum of the scaling exponents, and Ps(Y), the scaled Probability Distribution Function (PDFs), from the raw PDFs of the variable X at various scales tau , P(X,tau), with the following scaling: P(X,tau) tau ^s(Y)=Ps(Y) with Y= X/tau ^s(Y) The first (direct) method is to use range-limited structure functions in a sufficiently small range of the scaled variable Y and search for the value of monofroctal exponent s(Y). A drawback of this approach is that the range of Y must be large enough to ensure that the statistics is meaningful. As a consequence, some cross-over behavior between fluctuations with different monofractal exponents can lead to an ambiguity with several solutions s(Y) for some ranges of Y. Also the multifractal spectrum produced is step-wise discontinuous. To overcome these difficulties, Wu & Chang (2011) have suggested a refined method where a value of the parameter s is assumed and the corresponding value of Y ensuring a collapse of the raw PDFs is searched for. The advantage of this latter approach is that s(Y) and Ps(Y) can be obtained for single values of Y. The two ROMA methods and the partition function method are used on a set of intermittent magnetic field fluctuations observed by the Cluster spacecraft in the Earth's magnetospheric cusp. Results

  2. Numerical Simulation of the Effect about Groundwater Level Fluctuation on the Concentration of BTEX Dissolved into Source Zone

    NASA Astrophysics Data System (ADS)

    Sun, Liqun; Chen, Yudao; Jiang, Lingzhi; Cheng, Yaping

    2018-01-01

    The water level fluctuation of groundwater will affect the BTEX dissolution in the fuel leakage source zone. In order to study the effect, a leakage test of gasoline was performed in the sand-tank model in the laboratory, and the concentrations of BTEX along with water level were monitored over a long period. Combined with VISUAL MODFLOW software, RT3D module was used to simulate the concentrations of BTEX, and mass flux method was used to evaluate the effects of water level fluctuation on the BTEX dissolution. The results indicate that water level fluctuation can significantly increase the concentration of BTEX dissolved in the leakage source zone. The dissolved amount of BTEX can reach up to 2.4 times under the water level fluctuation condition. The method of numerical simulation combined with mass flux calculation can be used to evaluate the effect of water level fluctuation on BTEX dissolution.

  3. Age correction in monitoring audiometry: method to update OSHA age-correction tables to include older workers.

    PubMed

    Dobie, Robert A; Wojcik, Nancy C

    2015-07-13

    The US Occupational Safety and Health Administration (OSHA) Noise Standard provides the option for employers to apply age corrections to employee audiograms to consider the contribution of ageing when determining whether a standard threshold shift has occurred. Current OSHA age-correction tables are based on 40-year-old data, with small samples and an upper age limit of 60 years. By comparison, recent data (1999-2006) show that hearing thresholds in the US population have improved. Because hearing thresholds have improved, and because older people are increasingly represented in noisy occupations, the OSHA tables no longer represent the current US workforce. This paper presents 2 options for updating the age-correction tables and extending values to age 75 years using recent population-based hearing survey data from the US National Health and Nutrition Examination Survey (NHANES). Both options provide scientifically derived age-correction values that can be easily adopted by OSHA to expand their regulatory guidance to include older workers. Regression analysis was used to derive new age-correction values using audiometric data from the 1999-2006 US NHANES. Using the NHANES median, better-ear thresholds fit to simple polynomial equations, new age-correction values were generated for both men and women for ages 20-75 years. The new age-correction values are presented as 2 options. The preferred option is to replace the current OSHA tables with the values derived from the NHANES median better-ear thresholds for ages 20-75 years. The alternative option is to retain the current OSHA age-correction values up to age 60 years and use the NHANES-based values for ages 61-75 years. Recent NHANES data offer a simple solution to the need for updated, population-based, age-correction tables for OSHA. The options presented here provide scientifically valid and relevant age-correction values which can be easily adopted by OSHA to expand their regulatory guidance to

  4. A computer program for multiple decrement life table analyses.

    PubMed

    Poole, W K; Cooley, P C

    1977-06-01

    Life table analysis has traditionally been the tool of choice in analyzing distribution of "survival" times when a parametric form for the survival curve could not be reasonably assumed. Chiang, in two papers [1,2] formalized the theory of life table analyses in a Markov chain framework and derived maximum likelihood estimates of the relevant parameters for the analyses. He also discussed how the techniques could be generalized to consider competing risks and follow-up studies. Although various computer programs exist for doing different types of life table analysis [3] to date, there has not been a generally available, well documented computer program to carry out multiple decrement analyses, either by Chiang's or any other method. This paper describes such a program developed by Research Triangle Institute. A user's manual is available at printing costs which supplements the contents of this paper with a discussion of the formula used in the program listing.

  5. Ion isotropy and fluctuations in the solar wind

    NASA Technical Reports Server (NTRS)

    Kellogg, Paul J.; Lin, Naiguo

    1997-01-01

    The effects of measured fluctuations, with only general considerations as to their source, are considered. Data from interplanetary scintillations and fluctuations in plasma density provided data on electric fields, while fluctuations in magnetic fields are measured directly. Data from the unified radio and plasma experiment (URAP) on Ulysses is used to fill in higher frequency ranges, to assess the variations in the fluctuations with time and space, and to help to identify wave modes. It is shown that electric field fluctuations are of the right order of magnitude to maintain ion isotropy.

  6. Constructing increment-decrement life tables.

    PubMed

    Schoen, R

    1975-05-01

    A life table model which can recognize increments (or entrants) as well as decrements has proven to be of considerable value in the analysis of marital status patterns, labor force participation patterns, and other areas of substantive interest. Nonetheless, relatively little work has been done on the methodology of increment-decrement (or combined) life tables. The present paper reviews the general, recursive solution of Schoen and Nelson (1974), develops explicit solutions for three cases of particular interest, and compares alternative approaches to the construction of increment-decrement tables.

  7. Fluctuations of Attentional Networks and Default Mode Network during the Resting State Reflect Variations in Cognitive States: Evidence from a Novel Resting-state Experience Sampling Method.

    PubMed

    Van Calster, Laurens; D'Argembeau, Arnaud; Salmon, Eric; Peters, Frédéric; Majerus, Steve

    2017-01-01

    Neuroimaging studies have revealed the recruitment of a range of neural networks during the resting state, which might reflect a variety of cognitive experiences and processes occurring in an individual's mind. In this study, we focused on the default mode network (DMN) and attentional networks and investigated their association with distinct mental states when participants are not performing an explicit task. To investigate the range of possible cognitive experiences more directly, this study proposes a novel method of resting-state fMRI experience sampling, informed by a phenomenological investigation of the fluctuation of mental states during the resting state. We hypothesized that DMN activity would increase as a function of internal mentation and that the activity of dorsal and ventral networks would indicate states of top-down versus bottom-up attention at rest. Results showed that dorsal attention network activity fluctuated as a function of subjective reports of attentional control, providing evidence that activity of this network reflects the perceived recruitment of controlled attentional processes during spontaneous cognition. Activity of the DMN increased when participants reported to be in a subjective state of internal mentation, but not when they reported to be in a state of perception. This study provides direct evidence for a link between fluctuations of resting-state neural activity and fluctuations in specific cognitive processes.

  8. Elastic constants from microscopic strain fluctuations

    PubMed

    Sengupta; Nielaba; Rao; Binder

    2000-02-01

    Fluctuations of the instantaneous local Lagrangian strain epsilon(ij)(r,t), measured with respect to a static "reference" lattice, are used to obtain accurate estimates of the elastic constants of model solids from atomistic computer simulations. The measured strains are systematically coarse-grained by averaging them within subsystems (of size L(b)) of a system (of total size L) in the canonical ensemble. Using a simple finite size scaling theory we predict the behavior of the fluctuations as a function of L(b)/L and extract elastic constants of the system in the thermodynamic limit at nonzero temperature. Our method is simple to implement, efficient, and general enough to be able to handle a wide class of model systems, including those with singular potentials without any essential modification. We illustrate the technique by computing isothermal elastic constants of "hard" and "soft" disk triangular solids in two dimensions from Monte Carlo and molecular dynamics simulations. We compare our results with those from earlier simulations and theory.

  9. Fluctuation analysis of relativistic nucleus-nucleus collisions in emulsion chambers

    NASA Technical Reports Server (NTRS)

    Mcguire, Stephen C.

    1988-01-01

    An analytical technique was developed for identifying enhanced fluctuations in the angular distributions of secondary particles produced from relativistic nucleus-nucleus collisions. The method is applied under the assumption that the masses of the produced particles are small compared to their linear momenta. The importance of particles rests in the fact that enhanced fluctuations in the rapidity distributions is considered to be an experimental signal for the creation of the quark-gluon-plasma (QGP), a state of nuclear matter predicted from the quantum chromodynamics theory (QCD). In the approach, Monte Carlo simulations are employed that make use of a portable random member generator that allow the calculations to be performed on a desk-top computer. The method is illustrated with data taken from high altitude emulsion exposures and is immediately applicable to similar data from accelerator-based emulsion exposures.

  10. The Periodic Table as a Mnemonic Device for Writing Electronic Configurations

    NASA Astrophysics Data System (ADS)

    Mabrouk, Suzanne T.

    2003-08-01

    Lectures on electronic configurations often appear boring and intangible to many students. This topic can become engaging and interesting through the use of an interactive method based on the periodic table. Using a periodic table with shell and subshell designations in each square, students learn the patterns or the periodicity to the electronic configurations of the elements. Students are then encouraged to commit these patterns to memory through rehearsal in class. With the standard periodic table and the memorized patterns, students are shown that electronic configurations can be determined. Although students often appear mystified by the topic of electronic configurations, especially when its relevance to chemistry is absent, students' understanding can be improved easily by making connections and using analogy as the activity described here does.

  11. Statistical physics approaches to financial fluctuations

    NASA Astrophysics Data System (ADS)

    Wang, Fengzhong

    2009-12-01

    Complex systems attract many researchers from various scientific fields. Financial markets are one of these widely studied complex systems. Statistical physics, which was originally developed to study large systems, provides novel ideas and powerful methods to analyze financial markets. The study of financial fluctuations characterizes market behavior, and helps to better understand the underlying market mechanism. Our study focuses on volatility, a fundamental quantity to characterize financial fluctuations. We examine equity data of the entire U.S. stock market during 2001 and 2002. To analyze the volatility time series, we develop a new approach, called return interval analysis, which examines the time intervals between two successive volatilities exceeding a given value threshold. We find that the return interval distribution displays scaling over a wide range of thresholds. This scaling is valid for a range of time windows, from one minute up to one day. Moreover, our results are similar for commodities, interest rates, currencies, and for stocks of different countries. Further analysis shows some systematic deviations from a scaling law, which we can attribute to nonlinear correlations in the volatility time series. We also find a memory effect in return intervals for different time scales, which is related to the long-term correlations in the volatility. To further characterize the mechanism of price movement, we simulate the volatility time series using two different models, fractionally integrated generalized autoregressive conditional heteroscedasticity (FIGARCH) and fractional Brownian motion (fBm), and test these models with the return interval analysis. We find that both models can mimic time memory but only fBm shows scaling in the return interval distribution. In addition, we examine the volatility of daily opening to closing and of closing to opening. We find that each volatility distribution has a power law tail. Using the detrended fluctuation

  12. Projecting a Stand Table Through Time

    Treesearch

    Quang V. Cao; V. Clark Baldwin

    1999-01-01

    Stand tables provide number of trees per acre for each diameter class. This paper presents a general technique to predict a future stand table, based on the current stand table and future stand summary statistics such as trees and basal area per acre, and average diameter. The stand projection technique involves (a) predicting surviving trees for each class, and (b)...

  13. Round-the-table teaching: a novel approach to resuscitation education.

    PubMed

    McGarvey, Kathryn; Scott, Karen; O'Leary, Fenton

    2014-10-01

    Effective cardiopulmonary resuscitation saves lives. Health professionals who care for acutely unwell children need to be prepared to care for a child in arrest. Hospitals must ensure that their staff have the knowledge, confidence and ability to respond to a child in cardiac arrest. RESUS4KIDS is a programme designed to teach paediatric resuscitation to health care professionals who care for acutely unwell children. The programme is delivered in two components: an e-learning component for pre-learning, followed by a short, practical, face-to-face course that is taught using the round-the-table teaching approach. Round-the-table teaching is a novel, evidence-based small group teaching approach designed to teach paediatric resuscitation skills and knowledge. Round-the-table teaching uses a structured approach to managing a collapsed child, and ensures that each participant has the opportunity to practise the essential resuscitation skills of airway manoeuvres, bag mask ventilation and cardiac compressions. Round-the-table teaching is an engaging, non-threatening approach to delivering interdisciplinary paediatric resuscitation education. The methodology ensures that all participants have the opportunity to practise each of the different essential skills associated with the Danger, Response, Send for help, Airway, Breathing, Circulation, Defibrillation or rhythm recognition (DRSABCD) approach to the collapsed child. Round-the-table teaching is based on evidence-based small group teaching methods. The methodology of round-the-table teaching can be applied to any topic where participants must demonstrate an understanding of a sequential approach to a clinical skill. Round-the-table teaching uses a structured approach to managing a collapsed child. © 2014 The Authors. The Clinical Teacher published by Association for the Study of Medical Education and John Wiley & Sons Ltd.

  14. Origin of density fluctuations in extended inflation

    NASA Technical Reports Server (NTRS)

    Kolb, Edward W.; Salopek, David S.; Turner, Michael S.

    1990-01-01

    The density fluctuations (both curvature and isocurvature) that arise due to quantum fluctuations in a simple model of extended inflation based upon the Jordan-Brans-Dicke theory are calculated. Curvature fluctuations arise due to quantum fluctuations in the Brans-Dicke field, in general have a nonscale-invariant spectrum, and can have an amplitude that is cosmologically acceptable and interesting without having to tune any coupling constant to a very small value. The density perturbations that arise due to the inflation field are subdominant. If there are other massless fields in the theory, e.g., an axion or an ilion, then isocurvature fluctuations arise in these fields too. Production of gravitational waves and the massless particles associated with excitations of the Brans-Dicke field are also discussed. Several attempts at more realistic models of extended inflation are also analyzed. The importance of the Einstein conformal frame in calculating curvature fluctuations is emphasized. When viewed in this frame, extended inflation closely resembles slow-rollover inflation with an exponential potential and the usual formula for the amplitude of curvature perturbations applies.

  15. Generalized noise terms for the quantized fluctuational electrodynamics

    NASA Astrophysics Data System (ADS)

    Partanen, Mikko; Häyrynen, Teppo; Tulkki, Jukka; Oksanen, Jani

    2017-03-01

    The quantization of optical fields in vacuum has been known for decades, but extending the field quantization to lossy and dispersive media in nonequilibrium conditions has proven to be complicated due to the position-dependent electric and magnetic responses of the media. In fact, consistent position-dependent quantum models for the photon number in resonant structures have only been formulated very recently and only for dielectric media. Here we present a general position-dependent quantized fluctuational electrodynamics (QFED) formalism that extends the consistent field quantization to describe the photon number also in the presence of magnetic field-matter interactions. It is shown that the magnetic fluctuations provide an additional degree of freedom in media where the magnetic coupling to the field is prominent. Therefore, the field quantization requires an additional independent noise operator that is commuting with the conventional bosonic noise operator describing the polarization current fluctuations in dielectric media. In addition to allowing the detailed description of field fluctuations, our methods provide practical tools for modeling optical energy transfer and the formation of thermal balance in general dielectric and magnetic nanodevices. We use QFED to investigate the magnetic properties of microcavity systems to demonstrate an example geometry in which it is possible to probe fields arising from the electric and magnetic source terms. We show that, as a consequence of the magnetic Purcell effect, the tuning of the position of an emitter layer placed inside a vacuum cavity can make the emissivity of a magnetic emitter to exceed the emissivity of a corresponding electric emitter.

  16. Food table on ISS

    NASA Image and Video Library

    2015-04-08

    ISS043E091650 (04/08/2015) --- A view of the food table located in the Russian Zvezda service module on the International Space Station taken by Expedition 43 Flight Engineer Scott Kelly. Assorted food, drink and condiment packets are visible. Kelly tweeted this image along with the comment: ""Looks messy, but it's functional. Our #food table on the @space station. What's for breakfast? #YearInSpace".

  17. Water Table Depth Reconstruction in Ombrotrophic Peatlands Using Biomarker Abundance Ratios and Compound-Specific Hydrogen Isotope Composition

    NASA Astrophysics Data System (ADS)

    Nichols, J. E.; Jackson, S. T.; Booth, R. K.; Pendall, E. G.; Huang, Y.

    2005-12-01

    Sediment cores from ombrotrophic peat bogs provide sensitive records of changes in precipitation/evaporation (P/E) balance. Various proxies have been developed to reconstruct surface moisture conditions in peat bogs, including testate amoebae, plant macrofossils, and peat humification. Studying species composition of testate amoeba assemblages is time consuming and requires specialized training. Humification index can be influenced by environmental factors other than moisture balance. The plant macrofossil proxy is less quantitative and cannot be performed on highly decomposed samples. We demonstrate that the ratio of C23 alkane to C29 alkane abundance may provide a simple alternative or complementary means of tracking peatland water-table depth. Data for this proxy can be collected quickly using a small sample (100 mg dry). Water-table depth decreases during drought, and abundance of Sphagnum, the dominant peat-forming genus, decreases as vascular plants increase. Sphagnum moss produces mainly medium chain-length alkanes (C21-C25) while vascular plants (grasses and shrubs) produce primarily longer chain-length alkanes (C27-C31). Therefore, C23:C29 n-alkane ratios quantitatively track the water table depth fluctuations in peat bogs. We compared C23:C29 n-alkane ratios in a core from Minden Bog (southeastern Michigan) with water table depth reconstructions based on testate-amoeba assemblages and humification. The 184-cm core spans the past ~3kyr of continuous peat deposition in the bog. Our results indicate that the alkane ratios closely track the water table depth variations, with C29 most abundant during droughts. We also explored the use of D/H ratios in Sphagnum biomarkers as a water-table depth proxy. Compound-specific hydrogen isotope ratio analyses were performed on Sphagnum biomarkers: C23 and C25 alkane and C24 acid. Dry periods are represented in these records by an enrichment of deuterium in these Sphagnum-specific compounds. These events also correlate

  18. Analysis of hydrodynamic fluctuations in heterogeneous adjacent multidomains in shear flow

    NASA Astrophysics Data System (ADS)

    Bian, Xin; Deng, Mingge; Tang, Yu-Hang; Karniadakis, George Em

    2016-03-01

    We analyze hydrodynamic fluctuations of a hybrid simulation under shear flow. The hybrid simulation is based on the Navier-Stokes (NS) equations on one domain and dissipative particle dynamics (DPD) on the other. The two domains overlap, and there is an artificial boundary for each one within the overlapping region. To impose the artificial boundary of the NS solver, a simple spatial-temporal averaging is performed on the DPD simulation. In the artificial boundary of the particle simulation, four popular strategies of constraint dynamics are implemented, namely the Maxwell buffer [Hadjiconstantinou and Patera, Int. J. Mod. Phys. C 08, 967 (1997), 10.1142/S0129183197000837], the relaxation dynamics [O'Connell and Thompson, Phys. Rev. E 52, R5792 (1995), 10.1103/PhysRevE.52.R5792], the least constraint dynamics [Nie et al., J. Fluid Mech. 500, 55 (2004), 10.1017/S0022112003007225; Werder et al., J. Comput. Phys. 205, 373 (2005), 10.1016/j.jcp.2004.11.019], and the flux imposition [Flekkøy et al., Europhys. Lett. 52, 271 (2000), 10.1209/epl/i2000-00434-8], to achieve a target mean value given by the NS solver. Going beyond the mean flow field of the hybrid simulations, we investigate the hydrodynamic fluctuations in the DPD domain. Toward that end, we calculate the transversal autocorrelation functions of the fluctuating variables in k space to evaluate the generation, transport, and dissipation of fluctuations in the presence of a hybrid interface. We quantify the unavoidable errors in the fluctuations, due to both the truncation of the domain and the constraint dynamics performed in the artificial boundary. Furthermore, we compare the four methods of constraint dynamics and demonstrate how to reduce the errors in fluctuations. The analysis and findings of this work are directly applicable to other hybrid simulations of fluid flow with thermal fluctuations.

  19. A Shot Number Based Approach to Performance Analysis in Table Tennis

    PubMed Central

    Yoshida, Kazuto; Yamada, Koshi

    2017-01-01

    Abstract The current study proposes a novel approach that improves the conventional performance analysis in table tennis by introducing the concept of frequency, or the number of shots, of each shot number. The improvements over the conventional method are as follows: better accuracy of the evaluation of skills and tactics of players, additional insights into scoring and returning skills and ease of understanding the results with a single criterion. The performance analysis of matches played at the 2012 Summer Olympics in London was conducted using the proposed method. The results showed some effects of the shot number and gender differences in table tennis. Furthermore, comparisons were made between Chinese players and players from other countries, what threw light on the skills and tactics of the Chinese players. The present findings demonstrate that the proposed method provides useful information and has some advantages over the conventional method. PMID:28210334

  20. Environmental Regulatory Update Table, October 1991

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

    Houlberg, L.M.; Hawkins, G.T.; Salk, M.S.

    1991-11-01

    The Environmental Regulatory Update Table provides information on regulatory initiatives of interest to DOE operations and contractor staff with environmental management responsibilities. The table is updated each month with information from the Federal Register and other sources, including direct contact with regulatory agencies. Each table entry provides a chronological record of the rulemaking process for that initiative with an abstract and a projection of further action.

  1. Environmental Regulatory Update Table, December 1991

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

    Houlberg, L.M.; Hawkins, G.T.; Salk, M.S.

    1992-01-01

    The Environmental Regulatory Update Table provides information on regulatory initiatives of interest to DOE operations and contractor staff with environmental management responsibilities. The table is updated each month with information from the Federal Register and other sources, including direct contact with regulatory agencies. Each table entry provides a chronological record of the rulemaking process for that initiative with an abstract and a projection of further action.

  2. Environmental Regulatory Update Table, September 1991

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

    Houlberg, L.M.; Hawkins, G.T.; Salk, M.S.

    1991-10-01

    The Environmental Regulatory Update Table provides information on regulatory initiatives of interest to DOE operations and contractor staff with environmental management responsibilities. The table is updated each month with information from the Federal Register and other sources, including direct contact with regulatory agencies. Each table entry provides a chronological record of the rulemaking process for that initiative with an abstract and a projection of further action.

  3. Environmental Regulatory Update Table, November 1991

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

    Houlberg, L.M.; Hawkins, G.T.; Salk, M.S.

    1991-12-01

    The Environmental Regulatory Update Table provides information on regulatory initiatives of interest to DOE operations and contractor staff with environmental management responsibilities. The table is updated each month with information from the Federal Register and other sources, including direct contact with regulatory agencies. Each table entry provides a chronological record of the rulemaking process for that initiative with an abstract and a projection of further action.

  4. Probability distribution functions for intermittent scrape-off layer plasma fluctuations

    NASA Astrophysics Data System (ADS)

    Theodorsen, A.; Garcia, O. E.

    2018-03-01

    A stochastic model for intermittent fluctuations in the scrape-off layer of magnetically confined plasmas has been constructed based on a super-position of uncorrelated pulses arriving according to a Poisson process. In the most common applications of the model, the pulse amplitudes are assumed exponentially distributed, supported by conditional averaging of large-amplitude fluctuations in experimental measurement data. This basic assumption has two potential limitations. First, statistical analysis of measurement data using conditional averaging only reveals the tail of the amplitude distribution to be exponentially distributed. Second, exponentially distributed amplitudes leads to a positive definite signal which cannot capture fluctuations in for example electric potential and radial velocity. Assuming pulse amplitudes which are not positive definite often make finding a closed form for the probability density function (PDF) difficult, even if the characteristic function remains relatively simple. Thus estimating model parameters requires an approach based on the characteristic function, not the PDF. In this contribution, the effect of changing the amplitude distribution on the moments, PDF and characteristic function of the process is investigated and a parameter estimation method using the empirical characteristic function is presented and tested on synthetically generated data. This proves valuable for describing intermittent fluctuations of all plasma parameters in the boundary region of magnetized plasmas.

  5. Measuring and comparing structural fluctuation patterns in large protein datasets.

    PubMed

    Fuglebakk, Edvin; Echave, Julián; Reuter, Nathalie

    2012-10-01

    The function of a protein depends not only on its structure but also on its dynamics. This is at the basis of a large body of experimental and theoretical work on protein dynamics. Further insight into the dynamics-function relationship can be gained by studying the evolutionary divergence of protein motions. To investigate this, we need appropriate comparative dynamics methods. The most used dynamical similarity score is the correlation between the root mean square fluctuations (RMSF) of aligned residues. Despite its usefulness, RMSF is in general less evolutionarily conserved than the native structure. A fundamental issue is whether RMSF is not as conserved as structure because dynamics is less conserved or because RMSF is not the best property to use to study its conservation. We performed a systematic assessment of several scores that quantify the (dis)similarity between protein fluctuation patterns. We show that the best scores perform as well as or better than structural dissimilarity, as assessed by their consistency with the SCOP classification. We conclude that to uncover the full extent of the evolutionary conservation of protein fluctuation patterns, it is important to measure the directions of fluctuations and their correlations between sites. Nathalie.Reuter@mbi.uib.no Supplementary data are available at Bioinformatics Online.

  6. Study of the TRAC Airfoil Table Computational System

    NASA Technical Reports Server (NTRS)

    Hu, Hong

    1999-01-01

    The report documents the study of the application of the TRAC airfoil table computational package (TRACFOIL) to the prediction of 2D airfoil force and moment data over a wide range of angle of attack and Mach number. The TRACFOIL generates the standard C-81 airfoil table for input into rotorcraft comprehensive codes such as CAM- RAD. The existing TRACFOIL computer package is successfully modified to run on Digital alpha workstations and on Cray-C90 supercomputers. A step-by-step instruction for using the package on both computer platforms is provided. Application of the newer version of TRACFOIL is made for two airfoil sections. The C-81 data obtained using the TRACFOIL method are compared with those of wind-tunnel data and results are presented.

  7. Elucidating fluctuating diffusivity in center-of-mass motion of polymer models with time-averaged mean-square-displacement tensor

    NASA Astrophysics Data System (ADS)

    Miyaguchi, Tomoshige

    2017-10-01

    There have been increasing reports that the diffusion coefficient of macromolecules depends on time and fluctuates randomly. Here a method is developed to elucidate this fluctuating diffusivity from trajectory data. Time-averaged mean-square displacement (MSD), a common tool in single-particle-tracking (SPT) experiments, is generalized to a second-order tensor with which both magnitude and orientation fluctuations of the diffusivity can be clearly detected. This method is used to analyze the center-of-mass motion of four fundamental polymer models: the Rouse model, the Zimm model, a reptation model, and a rigid rodlike polymer. It is found that these models exhibit distinctly different types of magnitude and orientation fluctuations of diffusivity. This is an advantage of the present method over previous ones, such as the ergodicity-breaking parameter and a non-Gaussian parameter, because with either of these parameters it is difficult to distinguish the dynamics of the four polymer models. Also, the present method of a time-averaged MSD tensor could be used to analyze trajectory data obtained in SPT experiments.

  8. [Comments on the use of the "life-table method" in orthopedics].

    PubMed

    Hassenpflug, J; Hahne, H J; Hedderich, J

    1992-01-01

    In the description of long term results, e.g. of joint replacements, survivorship analysis is used increasingly in orthopaedic surgery. The survivorship analysis is more useful to describe the frequency of failure rather than global statements in percentage. The relative probability of failure for fixed intervals is drawn from the number of controlled patients and the frequency of failure. The complementary probabilities of success are linked in their temporal sequence thus representing the probability of survival at a fixed endpoint. Necessary condition for the use of this procedure is the exact definition of moment and manner of failure. It is described how to establish survivorship tables.

  9. Virtual World Currency Value Fluctuation Prediction System Based on User Sentiment Analysis.

    PubMed

    Kim, Young Bin; Lee, Sang Hyeok; Kang, Shin Jin; Choi, Myung Jin; Lee, Jung; Kim, Chang Hun

    2015-01-01

    In this paper, we present a method for predicting the value of virtual currencies used in virtual gaming environments that support multiple users, such as massively multiplayer online role-playing games (MMORPGs). Predicting virtual currency values in a virtual gaming environment has rarely been explored; it is difficult to apply real-world methods for predicting fluctuating currency values or shares to the virtual gaming world on account of differences in domains between the two worlds. To address this issue, we herein predict virtual currency value fluctuations by collecting user opinion data from a virtual community and analyzing user sentiments or emotions from the opinion data. The proposed method is straightforward and applicable to predicting virtual currencies as well as to gaming environments, including MMORPGs. We test the proposed method using large-scale MMORPGs and demonstrate that virtual currencies can be effectively and efficiently predicted with it.

  10. Virtual World Currency Value Fluctuation Prediction System Based on User Sentiment Analysis

    PubMed Central

    Kim, Young Bin; Lee, Sang Hyeok; Kang, Shin Jin; Choi, Myung Jin; Lee, Jung; Kim, Chang Hun

    2015-01-01

    In this paper, we present a method for predicting the value of virtual currencies used in virtual gaming environments that support multiple users, such as massively multiplayer online role-playing games (MMORPGs). Predicting virtual currency values in a virtual gaming environment has rarely been explored; it is difficult to apply real-world methods for predicting fluctuating currency values or shares to the virtual gaming world on account of differences in domains between the two worlds. To address this issue, we herein predict virtual currency value fluctuations by collecting user opinion data from a virtual community and analyzing user sentiments or emotions from the opinion data. The proposed method is straightforward and applicable to predicting virtual currencies as well as to gaming environments, including MMORPGs. We test the proposed method using large-scale MMORPGs and demonstrate that virtual currencies can be effectively and efficiently predicted with it. PMID:26241496

  11. Macroscopic behavior and fluctuation-dissipation response of stochastic ecohydrological systems

    NASA Astrophysics Data System (ADS)

    Porporato, A. M.

    2017-12-01

    The coupled dynamics of water, carbon and nutrient cycles in ecohydrological systems is forced by unpredictable and intermittent hydroclimatic fluctuations at different time scales. While modeling and long-term prediction of these complex interactions often requires a probabilistic approach, the resulting stochastic equations however are only solvable in special cases. To obtain information on the behavior of the system one typically has to resort to approximation methods. Here we discuss macroscopic equations for the averages and fluctuation-dissipation estimates for the general correlations between the forcing and the ecohydrological response for the soil moisture-plant biomass interaction and the problem of primary salinization and nitrogen retention in soils.

  12. New Tables For IABG's 320kN Shaker System: Design And Procurement Process

    NASA Astrophysics Data System (ADS)

    Baumgartl, Ralf

    2012-07-01

    For more than 25 years IABG is operating its 320kN vibration system in testing of space and non-space applications. The vibration system is a multi shaker system, using four electrodynamic shakers, driving a 3x3m2 head expander and a 3x3m2 slip table. During the recent years a modernisation program of the shaker system has been implemented. The purpose of this program was to exchange system components, which have reached their expected duration of life, as well as to exchange components which did no longer fulfil the state-of-the-art requirements in testing and thus to adapt the vibration system to future challenges. Two major components of the shaker system, which have been covered during the modernisation program, are the shaker tables (the head expander and the slip table). Being the direct interface of a vibration test facility to a specimen, the shaker tables are crucial regarding the shaker system overall performance. And this fact applies even more for shaker systems with large tables, because there are no off-the-shelf solutions in this area. During the recent 5 years IABG specified, designed and procured a new head expander and a new slip table for the 320kN shaker system. This paper describes the overall process investigating on the following listed aspects: - general requirements for the tables - definition of boundary conditions and guidance principles - specific areas of interest - definition of the table material and the manufacturing method - design solutions - challenges during manufacturing - results - table properties

  13. Non-tables look-up search algorithm for efficient H.264/AVC context-based adaptive variable length coding decoding

    NASA Astrophysics Data System (ADS)

    Han, Yishi; Luo, Zhixiao; Wang, Jianhua; Min, Zhixuan; Qin, Xinyu; Sun, Yunlong

    2014-09-01

    In general, context-based adaptive variable length coding (CAVLC) decoding in H.264/AVC standard requires frequent access to the unstructured variable length coding tables (VLCTs) and significant memory accesses are consumed. Heavy memory accesses will cause high power consumption and time delays, which are serious problems for applications in portable multimedia devices. We propose a method for high-efficiency CAVLC decoding by using a program instead of all the VLCTs. The decoded codeword from VLCTs can be obtained without any table look-up and memory access. The experimental results show that the proposed algorithm achieves 100% memory access saving and 40% decoding time saving without degrading video quality. Additionally, the proposed algorithm shows a better performance compared with conventional CAVLC decoding, such as table look-up by sequential search, table look-up by binary search, Moon's method, and Kim's method.

  14. Nonisothermal fluctuating hydrodynamics and Brownian motion

    NASA Astrophysics Data System (ADS)

    Falasco, G.; Kroy, K.

    2016-03-01

    The classical theory of Brownian dynamics follows from coarse graining the underlying linearized fluctuating hydrodynamics of the solvent. We extend this procedure to globally nonisothermal conditions, requiring only a local thermal equilibration of the solvent. Starting from the conservation laws, we establish the stochastic equations of motion for the fluid momentum fluctuations in the presence of a suspended Brownian particle. These are then contracted to the nonisothermal generalized Langevin description of the suspended particle alone, for which the coupling to stochastic temperature fluctuations is found to be negligible under typical experimental conditions.

  15. 40 CFR Table E-1 to Subpart E of... - Summary of Test Requirements for Reference and Class I Equivalent Methods for PM2.5 and PM10-2.5

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Reference and Class I Equivalent Methods for PM2.5 and PM10-2.5 E Table E-1 to Subpart E of Part 53... MONITORING REFERENCE AND EQUIVALENT METHODS Procedures for Testing Physical (Design) and Performance Characteristics of Reference Methods and Class I and Class II Equivalent Methods for PM2.5 or PM10â2.5 Pt. 53...

  16. High-precision control of LSRM based X-Y table for industrial applications.

    PubMed

    Pan, J F; Cheung, Norbert C; Zou, Yu

    2013-01-01

    The design of an X-Y table applying direct-drive linear switched reluctance motor (LSRM) principle is proposed in this paper. The proposed X-Y table has the characteristics of low cost, simple and stable mechanical structure. After the design procedure is introduced, an adaptive position control method based on online parameter identification and pole-placement regulation scheme is developed for the X-Y table. Experimental results prove the feasibility and its priority over a traditional PID controller with better dynamic response, static performance and robustness to disturbances. It is expected that the novel two-dimensional direct-drive system find its applications in high-precision manufacture area. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.

  17. Environmental Regulatory Update Table, August 1991

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

    Houlberg, L.M., Hawkins, G.T.; Salk, M.S.

    1991-09-01

    This Environmental Regulatory Update Table (August 1991) provides information on regulatory initiatives of interest to DOE operations and contractor staff with environmental management responsibilities. The table is updated each month with information from the Federal Register and other sources, including direct contact with regulatory agencies. Each table entry provides a chronological record of the rulemaking process for that initiative with an abstract and a projection of further action.

  18. Online Periodic Table: A Cautionary Note

    NASA Astrophysics Data System (ADS)

    Izci, Kemal; Barrow, Lloyd H.; Thornhill, Erica

    2013-08-01

    The purpose of this study was (a) to evaluate ten online periodic table sources for their accuracy and (b) to compare the types of information and links provided to users. Limited studies have been reported on online periodic table (Diener and Moore 2011; Slocum and Moore in J Chem Educ 86(10):1167, 2009). Chemistry students' understanding of periodic table is vital for their success in chemistry, and the online periodic table has the potential to advance learners' understanding of chemical elements and fundamental chemistry concepts (Brito et al. in J Res Sci Teach 42(1):84-111, 2005). The ten sites were compared for accuracy of data with the Handbook of Chemistry and Physics (HCP, Haynes in CRC handbook of chemistry and physics: a ready-reference book of chemical and physical data. CRC Press, Boca Raton 2012). The 10 sites are the most visited periodic table Web sites available. Four different elements, carbon, gold, argon, and plutonium, were selected for comparison, and 11 different attributes for each element were identified for evaluating accuracy. A wide variation of accuracy was found among the 10 periodic table sources. Chemicool was the most accurate information provider with 66.67 % accuracy when compared to the HCP. The 22 types of information including meaning of name and use in industry and society provided by these sites were, also, compared. WebElements, "Chemicool", "Periodic Table Live", and "the Photographic Periodic Table of the Elements" were the most information providers, providing 86.36 % of information among the 10 Web sites. "WebElements" provides the most links among the 10 Web sites. It was concluded that if an individual teacher or student desires only raw physical data from element, the Internet might not be the best choice.

  19. Energy transfer between two vacuum-gapped metal plates: Coulomb fluctuations and electron tunneling

    NASA Astrophysics Data System (ADS)

    Zhang, Zu-Quan; Lü, Jing-Tao; Wang, Jian-Sheng

    2018-05-01

    Recent experimental measurements for near-field radiative heat transfer between two bodies have been able to approach the gap distance within 2 nm , where the contributions of Coulomb fluctuation and electron tunneling are comparable. Using the nonequilibrium Green's function method in the G0W0 approximation, based on a tight-binding model, we obtain for the energy current a Caroli formula from the Meir-Wingreen formula in the local equilibrium approximation. Also, the Caroli formula is consistent with the evanescent part of the heat transfer from the theory of fluctuational electrodynamics. We go beyond the local equilibrium approximation to study the energy transfer in the crossover region from electron tunneling to Coulomb fluctuation based on a numerical calculation.

  20. Density Fluctuations in a Polar Coronal Hole

    NASA Astrophysics Data System (ADS)

    Hahn, Michael; D’Huys, Elke; Savin, Daniel Wolf

    2018-06-01

    We have measured the root-mean-square (rms) amplitude of intensity fluctuations, ΔI, in plume and interplume regions of a polar coronal hole. These intensity fluctuations correspond to density fluctuations. Using data from the Sun Watcher using the Active Pixel System detector and Image Processing on the Project for Onboard Autonomy (Proba2), our results extend up to a height of about 1.35 R ⊙. One advantage of the rms analysis is that it does not rely on a detailed evaluation of the power spectrum, which is limited by noise levels to low heights in the corona. The rms approach can be performed up to larger heights where the noise level is greater, provided that the noise itself can be quantified. At low heights, both the absolute ΔI, and the amplitude relative to the mean intensity, ΔI/I, decrease with height. However, starting at about 1.2 R ⊙, ΔI/I increases, reaching 20%–40% by 1.35 R ⊙. This corresponds to density fluctuations of Δn e/n e ≈ 10%–20%. The increasing relative amplitude implies that the density fluctuations are generated in the corona itself. One possibility is that the density fluctuations are generated by an instability of Alfvén waves. This generation mechanism is consistent with some theoretical models and with observations of Alfvén wave amplitudes in coronal holes. Although we find that the energy of the observed density fluctuations is small, these fluctuations are likely to play an important indirect role in coronal heating by promoting the reflection of Alfvén waves and driving turbulence.

  1. Automatic Extraction of Drug Adverse Effects from Product Characteristics (SPCs): A Text Versus Table Comparison.

    PubMed

    Lamy, Jean-Baptiste; Ugon, Adrien; Berthelot, Hélène

    2016-01-01

    Potential adverse effects (AEs) of drugs are described in their summary of product characteristics (SPCs), a textual document. Automatic extraction of AEs from SPCs is useful for detecting AEs and for building drug databases. However, this task is difficult because each AE is associated with a frequency that must be extracted and the presentation of AEs in SPCs is heterogeneous, consisting of plain text and tables in many different formats. We propose a taxonomy for the presentation of AEs in SPCs. We set up natural language processing (NLP) and table parsing methods for extracting AEs from texts and tables of any format, and evaluate them on 10 SPCs. Automatic extraction performed better on tables than on texts. Tables should be recommended for the presentation of the AEs section of the SPCs.

  2. Effects of redox fluctuations on microbial community ecology post-wildfire in a high elevation mixed-conifer catchment in northern New Mexico.

    NASA Astrophysics Data System (ADS)

    Fairbanks, D.; Green, K.; Murphy, M. A.; Shepard, C.; Chorover, J.; Rich, V. I.; Gallery, R. E.

    2015-12-01

    Wildfires are increasing in size and severity across the western United States with impacts on regional biogeochemical cycling. The resiliency of resident soil microbial communities determines rates of nutrient transformations as well as forest structure and recovery. Redox conditions in soil determine metabolic activities of microorganisms, which first consume oxygen and a succession of alternative terminal electron acceptors to support growth and metabolism using a variety of carbon sources. Controls on redox zonation are largely unknown in dominantly oxic soils, and microbial community adaptation and response to fluctuations in redox potential in a sub-alpine forested post-disturbance catchment has not been studied. Previous work has shown that fluctuating or rising water tables result in redox-dynamic sites, which can be 'hot spots' of biogeochemical activity depending on landscape position. Fire-induced tree mortality results in altered hydrologic flow paths and decreased evapotranspiration, leading to potential for intensified hot spot activity. We are testing such coupling of microbial activity with fluctuations in redox status using field measurements and laboratory incubation experiments. The 2013 Thompson Ridge Fire in the Jemez River Basin (NM) Critical Zone Observatory provides a highly-contextualized opportunity to examine how disturbance regime affects changes in soil microbial community dynamics and fluctuations in reduction-oxidation potential (as quantified by continuous CZO measurements of O2, CO2 and Eh as a function of soil depth and landscape location). We hypothesize that areas of depositional convergence in the catchment, which have been shown to exhibit more reducing conditions, will host microbial communities that are better adapted to fluctuating redox conditions and exhibit a greater diversity in functional capabilities. In these mixed conifer forests we find shifts in redox potential status in relation to depth and topography where more

  3. Contribution of spontaneous polarization and its fluctuations to refraction of light in ferroelectrics

    NASA Astrophysics Data System (ADS)

    Markovin, P. A.; Trepakov, V. A.; Tagantsev, A. K.; Deineka, A.; Andreev, D. A.

    2016-01-01

    The expressions for the spontaneous polar contribution δ n i s to the principal values of the refractive index due to the quadratic electro-optic effect in ferroelectrics have been considered within the phenomenological approach taking into account the polarization fluctuations. A method has been proposed for calculating the magnitude and temperature dependence of the root-mean-square fluctuations of the polarization (short-range local polar order) P sh = < P fl 2 >1/2 below the ferroelectric transition temperature T c from temperature changes in the spontaneous polar contribution δ n i s ( T) if the average spontaneous polarization P s = < P> characterizing the long-range order is determined from independent measurements (for example, from dielectric hysteresis loops). For the case of isotropic fluctuations, the proposed method has made it possible to calculate P sh and P s only from refractometric measurements. It has been shown that, upon interferometric measurements, the method developed in this work allows calculating P sh and P s directly from the measured temperature and electric-field changes in the relative optical path (the specific optical retardation) of the light.

  4. SGFSC: speeding the gene functional similarity calculation based on hash tables.

    PubMed

    Tian, Zhen; Wang, Chunyu; Guo, Maozu; Liu, Xiaoyan; Teng, Zhixia

    2016-11-04

    In recent years, many measures of gene functional similarity have been proposed and widely used in all kinds of essential research. These methods are mainly divided into two categories: pairwise approaches and group-wise approaches. However, a common problem with these methods is their time consumption, especially when measuring the gene functional similarities of a large number of gene pairs. The problem of computational efficiency for pairwise approaches is even more prominent because they are dependent on the combination of semantic similarity. Therefore, the efficient measurement of gene functional similarity remains a challenging problem. To speed current gene functional similarity calculation methods, a novel two-step computing strategy is proposed: (1) establish a hash table for each method to store essential information obtained from the Gene Ontology (GO) graph and (2) measure gene functional similarity based on the corresponding hash table. There is no need to traverse the GO graph repeatedly for each method with the help of the hash table. The analysis of time complexity shows that the computational efficiency of these methods is significantly improved. We also implement a novel Speeding Gene Functional Similarity Calculation tool, namely SGFSC, which is bundled with seven typical measures using our proposed strategy. Further experiments show the great advantage of SGFSC in measuring gene functional similarity on the whole genomic scale. The proposed strategy is successful in speeding current gene functional similarity calculation methods. SGFSC is an efficient tool that is freely available at http://nclab.hit.edu.cn/SGFSC . The source code of SGFSC can be downloaded from http://pan.baidu.com/s/1dFFmvpZ .

  5. [COSMOS motion design optimization in the CT table].

    PubMed

    Shang, Hong; Huang, Jian; Ren, Chao

    2013-03-01

    Through the CT Table dynamic simulation by COSMOS Motion, analysis the hinge of table and the motor force, then optimize the position of the hinge of table, provide the evidence of selecting bearing and motor, meanwhile enhance the design quality of the CT table and reduce the product design cost.

  6. ‘Valley Pearl’ table grape

    USDA-ARS?s Scientific Manuscript database

    ‘Valley Pearl’ is an early to mid-season, white seedless table grape (Vitis vinifera L.) suitable for commercial table grape production where V. vinifera can be grown. Significant characteristics of ‘Valley Pearl’ are its high and consistent fruit production on spur pruned vines and large round berr...

  7. Layout optimization with assist features placement by model based rule tables for 2x node random contact

    NASA Astrophysics Data System (ADS)

    Jun, Jinhyuck; Park, Minwoo; Park, Chanha; Yang, Hyunjo; Yim, Donggyu; Do, Munhoe; Lee, Dongchan; Kim, Taehoon; Choi, Junghoe; Luk-Pat, Gerard; Miloslavsky, Alex

    2015-03-01

    As the industry pushes to ever more complex illumination schemes to increase resolution for next generation memory and logic circuits, sub-resolution assist feature (SRAF) placement requirements become increasingly severe. Therefore device manufacturers are evaluating improvements in SRAF placement algorithms which do not sacrifice main feature (MF) patterning capability. There are known-well several methods to generate SRAF such as Rule based Assist Features (RBAF), Model Based Assist Features (MBAF) and Hybrid Assisted Features combining features of the different algorithms using both RBAF and MBAF. Rule Based Assist Features (RBAF) continue to be deployed, even with the availability of Model Based Assist Features (MBAF) and Inverse Lithography Technology (ILT). Certainly for the 3x nm node, and even at the 2x nm nodes and lower, RBAF is used because it demands less run time and provides better consistency. Since RBAF is needed now and in the future, what is also needed is a faster method to create the AF rule tables. The current method typically involves making masks and printing wafers that contain several experiments, varying the main feature configurations, AF configurations, dose conditions, and defocus conditions - this is a time consuming and expensive process. In addition, as the technology node shrinks, wafer process changes and source shape redesigns occur more frequently, escalating the cost of rule table creation. Furthermore, as the demand on process margin escalates, there is a greater need for multiple rule tables: each tailored to a specific set of main-feature configurations. Model Assisted Rule Tables(MART) creates a set of test patterns, and evaluates the simulated CD at nominal conditions, defocused conditions and off-dose conditions. It also uses lithographic simulation to evaluate the likelihood of AF printing. It then analyzes the simulation data to automatically create AF rule tables. It means that analysis results display the cost of

  8. Medical management of motor fluctuations.

    PubMed

    Dewey, Richard B

    2008-08-01

    Given the magnitude of the problem of motor fluctuations in patients who have Parkinson's disease treated with levodopa, a significant effort has been expended by physicians, researchers, and pharmaceutical manufacturers over the years to find effective treatments. This article briefly reviews the medical options for managing motor fluctuations that are in common use in the United States or that are expected to be available soon.

  9. The Periodic Table as a Mnemonic Device for Writing Electronic Configurations.

    ERIC Educational Resources Information Center

    Mabrouk, Suzanne T.

    2003-01-01

    Presents an interactive method for using the periodic table as an effective mnemonic for writing electronic configurations. Discusses the intrinsic relevance of configurations to chemistry by building upon past analogies. Addresses pertinent background information, describes the hands-on method, and demonstrates its use. Transforms the traditional…

  10. Lookup Tables Versus Stacked Rasch Analysis in Comparing Pre- and Postintervention Adult Strabismus-20 Data.

    PubMed

    Leske, David A; Hatt, Sarah R; Liebermann, Laura; Holmes, Jonathan M

    2016-02-01

    We compare two methods of analysis for Rasch scoring pre- to postintervention data: Rasch lookup table versus de novo stacked Rasch analysis using the Adult Strabismus-20 (AS-20). One hundred forty-seven subjects completed the AS-20 questionnaire prior to surgery and 6 weeks postoperatively. Subjects were classified 6 weeks postoperatively as "success," "partial success," or "failure" based on angle and diplopia status. Postoperative change in AS-20 scores was compared for all four AS-20 domains (self-perception, interactions, reading function, and general function) overall and by success status using two methods: (1) applying historical Rasch threshold measures from lookup tables and (2) performing a stacked de novo Rasch analysis. Change was assessed by analyzing effect size, improvement exceeding 95% limits of agreement (LOA), and score distributions. Effect sizes were similar for all AS-20 domains whether obtained from lookup tables or stacked analysis. Similar proportions exceeded 95% LOAs using lookup tables versus stacked analysis. Improvement in median score was observed for all AS-20 domains using lookup tables and stacked analysis ( P < 0.0001 for all comparisons). The Rasch-scored AS-20 is a responsive and valid instrument designed to measure strabismus-specific health-related quality of life. When analyzing pre- to postoperative change in AS-20 scores, Rasch lookup tables and de novo stacked Rasch analysis yield essentially the same results. We describe a practical application of lookup tables, allowing the clinician or researcher to score the Rasch-calibrated AS-20 questionnaire without specialized software.

  11. Quasi-critical fluctuations: a novel state of matter?

    PubMed

    Bertel, Erminald

    2013-05-01

    Quasi-critical fluctuations occur close to critical points or close to continuous phase transitions. In three-dimensional systems, precision tuning is required to access the fluctuation regime. Lowering the dimensionality enhances the parameter space for quasi-critical fluctuations considerably. This enables one to make use of novel properties emerging in fluctuating systems, such as giant susceptibilities, Casimir forces or novel quasi-particle interactions. Examples are discussed ranging from simple metal-adsorbate systems to unconventional superconductivity in iron-based superconductors.

  12. Spatial fluctuations in transient creep deformation

    NASA Astrophysics Data System (ADS)

    Laurson, Lasse; Rosti, Jari; Koivisto, Juha; Miksic, Amandine; Alava, Mikko J.

    2011-07-01

    We study the spatial fluctuations of transient creep deformation of materials as a function of time, both by digital image correlation (DIC) measurements of paper samples and by numerical simulations of a crystal plasticity or discrete dislocation dynamics model. This model has a jamming or yielding phase transition, around which power law or Andrade creep is found. During primary creep, the relative strength of the strain rate fluctuations increases with time in both cases—the spatially averaged creep rate obeys the Andrade law epsilont ~ t - 0.7, while the time dependence of the spatial fluctuations of the local creep rates is given by Δepsilont ~ t - 0.5. A similar scaling for the fluctuations is found in the logarithmic creep regime that is typically observed for lower applied stresses. We review briefly some classical theories of Andrade creep from the point of view of such spatial fluctuations. We consider these phenomenological, time-dependent creep laws in terms of a description based on a non-equilibrium phase transition separating evolving and frozen states of the system when the externally applied load is varied. Such an interpretation is discussed further by the data collapse of the local deformations in the spirit of absorbing state/depinning phase transitions, as well as deformation-deformation correlations and the width of the cumulative strain distributions. The results are also compared with the order parameter fluctuations observed close to the depinning transition of the 2d linear interface model or the quenched Edwards-Wilkinson equation.

  13. Reduction of magnetic field fluctuations in powered magnets for NMR using inductive measurements and sampled-data feedback control.

    PubMed

    Li, Mingzhou; Schiano, Jeffrey L; Samra, Jenna E; Shetty, Kiran K; Brey, William W

    2011-10-01

    Resistive and hybrid (resistive/superconducting) magnets provide substantially higher magnetic fields than those available in low-temperature superconducting magnets, but their relatively low spatial homogeneity and temporal field fluctuations are unacceptable for high resolution NMR. While several techniques for reducing temporal fluctuations have demonstrated varying degrees of success, this paper restricts attention to methods that utilize inductive measurements and feedback control to actively cancel the temporal fluctuations. In comparison to earlier studies using analog proportional control, this paper shows that shaping the controller frequency response results in significantly higher reductions in temporal fluctuations. Measurements of temporal fluctuation spectra and the frequency response of the instrumentation that cancels the temporal fluctuations guide the controller design. In particular, we describe a sampled-data phase-lead-lag controller that utilizes the internal model principle to selectively attenuate magnetic field fluctuations caused by the power supply ripple. We present a quantitative comparison of the attenuation in temporal fluctuations afforded by the new design and a proportional control design. Metrics for comparison include measurements of the temporal fluctuations using Faraday induction and observations of the effect that the fluctuations have on nuclear resonance measurements. Copyright © 2011. Published by Elsevier Inc.

  14. Stationary table CT dosimetry and anomalous scanner-reported values of CTDI{sub vol}

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

    Dixon, Robert L., E-mail: rdixon@wfubmc.edu; Boone, John M.

    2014-01-15

    Purpose: Anomalous, scanner-reported values of CTDI{sub vol} for stationary phantom/table protocols (having elevated values of CTDI{sub vol} over 300% higher than the actual dose to the phantom) have been observed; which are well-beyond the typical accuracy expected of CTDI{sub vol} as a phantom dose. Recognition of these outliers as “bad data” is important to users of CT dose index tracking systems (e.g., ACR DIR), and a method for recognition and correction is provided. Methods: Rigorous methods and equations are presented which describe the dose distributions for stationary-table CT. A comparison with formulae for scanner-reported values of CTDI{sub vol} clearly identifiesmore » the source of these anomalies. Results: For the stationary table, use of the CTDI{sub 100} formula (applicable to a moving phantom only) overestimates the dose due to extra scatter and also includes an overbeaming correction, both of which are nonexistent when the phantom (or patient) is held stationary. The reported DLP remains robust for the stationary phantom. Conclusions: The CTDI-paradigm does not apply in the case of a stationary phantom and simpler nonintegral equations suffice. A method of correction of the currently reported CTDI{sub vol} using the approach-to-equilibrium formula H(a) and an overbeaming correction factor serves to scale the reported CTDI{sub vol} values to more accurate levels for stationary-table CT, as well as serving as an indicator in the detection of “bad data.”.« less

  15. Asymptotics of QCD traveling waves with fluctuations and running coupling effects

    NASA Astrophysics Data System (ADS)

    Beuf, Guillaume

    2008-09-01

    Extending the Balitsky-Kovchegov (BK) equation independently to running coupling or to fluctuation effects due to pomeron loops is known to lead in both cases to qualitative changes of the traveling-wave asymptotic solutions. In this paper we study the extension of the forward BK equation, including both running coupling and fluctuations effects, extending the method developed for the fixed coupling case [E. Brunet, B. Derrida, A.H. Mueller, S. Munier, Phys. Rev. E 73 (2006) 056126, cond-mat/0512021]. We derive the exact asymptotic behavior in rapidity of the probabilistic distribution of the saturation scale.

  16. Thermodynamic constraints on fluctuation phenomena

    NASA Astrophysics Data System (ADS)

    Maroney, O. J. E.

    2009-12-01

    The relationships among reversible Carnot cycles, the absence of perpetual motion machines, and the existence of a nondecreasing globally unique entropy function form the starting point of many textbook presentations of the foundations of thermodynamics. However, the thermal fluctuation phenomena associated with statistical mechanics has been argued to restrict the domain of validity of this basis of the second law of thermodynamics. Here we demonstrate that fluctuation phenomena can be incorporated into the traditional presentation, extending rather than restricting the domain of validity of the phenomenologically motivated second law. Consistency conditions lead to constraints upon the possible spectrum of thermal fluctuations. In a special case this uniquely selects the Gibbs canonical distribution and more generally incorporates the Tsallis distributions. No particular model of microscopic dynamics need be assumed.

  17. Thermodynamic constraints on fluctuation phenomena.

    PubMed

    Maroney, O J E

    2009-12-01

    The relationships among reversible Carnot cycles, the absence of perpetual motion machines, and the existence of a nondecreasing globally unique entropy function form the starting point of many textbook presentations of the foundations of thermodynamics. However, the thermal fluctuation phenomena associated with statistical mechanics has been argued to restrict the domain of validity of this basis of the second law of thermodynamics. Here we demonstrate that fluctuation phenomena can be incorporated into the traditional presentation, extending rather than restricting the domain of validity of the phenomenologically motivated second law. Consistency conditions lead to constraints upon the possible spectrum of thermal fluctuations. In a special case this uniquely selects the Gibbs canonical distribution and more generally incorporates the Tsallis distributions. No particular model of microscopic dynamics need be assumed.

  18. Recharge characteristics of an unconfined aquifer from the rainfall-water table relationship

    NASA Astrophysics Data System (ADS)

    Viswanathan, M. N.

    1984-02-01

    The determination of recharge levels of unconfined aquifers, recharged entirely by rainfall, is done by developing a model for the aquifer that estimates the water-table levels from the history of rainfall observations and past water-table levels. In the present analysis, the model parameters that influence the recharge were not only assumed to be time dependent but also to have varying dependence rates for various parameters. Such a model is solved by the use of a recursive least-squares method. The variable-rate parameter variation is incorporated using a random walk model. From the field tests conducted at Tomago Sandbeds, Newcastle, Australia, it was observed that the assumption of variable rates of time dependency of recharge parameters produced better estimates of water-table levels compared to that with constant-recharge parameters. It was observed that considerable recharge due to rainfall occurred on the very same day of rainfall. The increase in water-table level was insignificant for subsequent days of rainfall. The level of recharge very much depends upon the intensity and history of rainfall. Isolated rainfalls, even of the order of 25 mm day -1, had no significant effect on the water-table levels.

  19. Methodological issues underlying multiple decrement life table analysis.

    PubMed

    Mode, C J; Avery, R C; Littman, G S; Potter, R G

    1977-02-01

    In this paper, the actuarial method of multiple decrement life table analysis of censored, longitudinal data is examined. The discussion is organized in terms of the first segment of usage of an intrauterine device. Weaknesses of the actuarial approach are pointed out, and an alternative approach, based on the classical model of competing risks, is proposed. Finally, the actuarial and the alternative method of analyzing censored data are compared, using data from the Taichung Medical Study on Intrauterine Devices.

  20. RAINIER: A simulation tool for distributions of excited nuclear states and cascade fluctuations

    NASA Astrophysics Data System (ADS)

    Kirsch, L. E.; Bernstein, L. A.

    2018-06-01

    A new code has been developed named RAINIER that simulates the γ-ray decay of discrete and quasi-continuum nuclear levels for a user-specified range of energy, angular momentum, and parity including a realistic treatment of level spacing and transition width fluctuations. A similar program, DICEBOX, uses the Monte Carlo method to simulate level and width fluctuations but is restricted in its initial level population algorithm. On the other hand, modern reaction codes such as TALYS and EMPIRE populate a wide range of states in the residual nucleus prior to γ-ray decay, but do not go beyond the use of deterministic functions and therefore neglect cascade fluctuations. This combination of capabilities allows RAINIER to be used to determine quasi-continuum properties through comparison with experimental data. Several examples are given that demonstrate how cascade fluctuations influence experimental high-resolution γ-ray spectra from reactions that populate a wide range of initial states.

  1. RAINIER: A simulation tool for distributions of excited nuclear states and cascade fluctuations

    DOE PAGES

    Kirsch, L. E.; Bernstein, L. A.

    2018-03-04

    In this paper, a new code has been developed named RAINIER that simulates the γ-ray decay of discrete and quasi-continuum nuclear levels for a user-specified range of energy, angular momentum, and parity including a realistic treatment of level spacing and transition width fluctuations. A similar program, DICEBOX, uses the Monte Carlo method to simulate level and width fluctuations but is restricted in its initial level population algorithm. On the other hand, modern reaction codes such as TALYS and EMPIRE populate a wide range of states in the residual nucleus prior to γ-ray decay, but do not go beyond the usemore » of deterministic functions and therefore neglect cascade fluctuations. This combination of capabilities allows RAINIER to be used to determine quasi-continuum properties through comparison with experimental data. Finally, several examples are given that demonstrate how cascade fluctuations influence experimental high-resolution γ-ray spectra from reactions that populate a wide range of initial states.« less

  2. RAINIER: A simulation tool for distributions of excited nuclear states and cascade fluctuations

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

    Kirsch, L. E.; Bernstein, L. A.

    In this paper, a new code has been developed named RAINIER that simulates the γ-ray decay of discrete and quasi-continuum nuclear levels for a user-specified range of energy, angular momentum, and parity including a realistic treatment of level spacing and transition width fluctuations. A similar program, DICEBOX, uses the Monte Carlo method to simulate level and width fluctuations but is restricted in its initial level population algorithm. On the other hand, modern reaction codes such as TALYS and EMPIRE populate a wide range of states in the residual nucleus prior to γ-ray decay, but do not go beyond the usemore » of deterministic functions and therefore neglect cascade fluctuations. This combination of capabilities allows RAINIER to be used to determine quasi-continuum properties through comparison with experimental data. Finally, several examples are given that demonstrate how cascade fluctuations influence experimental high-resolution γ-ray spectra from reactions that populate a wide range of initial states.« less

  3. Elasticity and Fluctuations of Frustrated Nanoribbons

    NASA Astrophysics Data System (ADS)

    Grossman, Doron; Sharon, Eran; Diamant, Haim

    2016-06-01

    We derive a reduced quasi-one-dimensional theory of geometrically frustrated elastic ribbons. Expressed in terms of geometric properties alone, it applies to ribbons over a wide range of scales, allowing the study of their elastic equilibrium, as well as thermal fluctuations. We use the theory to account for the twisted-to-helical transition of ribbons with spontaneous negative curvature and the effect of fluctuations on the corresponding critical exponents. The persistence length of such ribbons changes nonmonotonically with the ribbon's width, dropping to zero at the transition. This and other statistical properties qualitatively differ from those of nonfrustrated fluctuating filaments.

  4. Subcopula-based measure of asymmetric association for contingency tables.

    PubMed

    Wei, Zheng; Kim, Daeyoung

    2017-10-30

    For the analysis of a two-way contingency table, a new asymmetric association measure is developed. The proposed method uses the subcopula-based regression between the discrete variables to measure the asymmetric predictive powers of the variables of interest. Unlike the existing measures of asymmetric association, the subcopula-based measure is insensitive to the number of categories in a variable, and thus, the magnitude of the proposed measure can be interpreted as the degree of asymmetric association in the contingency table. The theoretical properties of the proposed subcopula-based asymmetric association measure are investigated. We illustrate the performance and advantages of the proposed measure using simulation studies and real data examples. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Some Reflections on the Periodic Table and Its Use.

    ERIC Educational Resources Information Center

    Fernelius, W. Conard

    1986-01-01

    Discusses early periodic tables; effect on the periodic table of atomic numbers; the periodic table in relation to electron distribution in the atoms of elements; terms and concepts related to the table; and the modern basis of the periodic table. Additional comments about these and other topics are included. (JN)

  6. 40 CFR Table C-1 to Subpart C of... - Test Concentration Ranges, Number of Measurements Required, and Maximum Discrepancy Specification

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Measurements Required, and Maximum Discrepancy Specification C Table C-1 to Subpart C of Part 53 Protection of... Reference Methods Pt. 53, Subpt. C, Table C-1 Table C-1 to Subpart C of Part 53—Test Concentration Ranges..., June 22, 2010, table C-1 to subpart C was revised, effective Aug. 23, 2010. For the convenience of the...

  7. 40 CFR Table 6 to Subpart Bbbb of... - Model Rule-Requirements for Validating Continuous Emission Monitoring Systems (CEMS)

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Continuous Emission Monitoring Systems (CEMS) 6 Table 6 to Subpart BBBB of Part 60 Protection of Environment... or Before August 30, 1999 Pt. 60, Subpt. BBBB, Table 6 Table 6 to Subpart BBBB of Part 60—Model Rule... levels Use the following methods in appendix A of this part to measure oxygen (or carbon dioxide) 1...

  8. 40 CFR Table 6 to Subpart Bbbb of... - Model Rule-Requirements for Validating Continuous Emission Monitoring Systems (CEMS)

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Continuous Emission Monitoring Systems (CEMS) 6 Table 6 to Subpart BBBB of Part 60 Protection of Environment... or Before August 30, 1999 Pt. 60, Subpt. BBBB, Table 6 Table 6 to Subpart BBBB of Part 60—Model Rule... levels Use the following methods in appendix A of this part to measure oxygen (or carbon dioxide) 1...

  9. Mapping water table depth using geophysical and environmental variables.

    PubMed

    Buchanan, S; Triantafilis, J

    2009-01-01

    Despite its importance, accurate representation of the spatial distribution of water table depth remains one of the greatest deficiencies in many hydrological investigations. Historically, both inverse distance weighting (IDW) and ordinary kriging (OK) have been used to interpolate depths. These methods, however, have major limitations: namely they require large numbers of measurements to represent the spatial variability of water table depth and they do not represent the variation between measurement points. We address this issue by assessing the benefits of using stepwise multiple linear regression (MLR) with three different ancillary data sets to predict the water table depth at 100-m intervals. The ancillary data sets used are Electromagnetic (EM34 and EM38), gamma radiometric: potassium (K), uranium (eU), thorium (eTh), total count (TC), and morphometric data. Results show that MLR offers significant precision and accuracy benefits over OK and IDW. Inclusion of the morphometric data set yielded the greatest (16%) improvement in prediction accuracy compared with IDW, followed by the electromagnetic data set (5%). Use of the gamma radiometric data set showed no improvement. The greatest improvement, however, resulted when all data sets were combined (37% increase in prediction accuracy over IDW). Significantly, however, the use of MLR also allows for prediction in variations in water table depth between measurement points, which is crucial for land management.

  10. Prediction of HR/BP response to the spontaneous breathing trial by fluctuation dissipation theory

    NASA Astrophysics Data System (ADS)

    Chen, Man

    2014-03-01

    We applied the non-equilibrium fluctuation dissipation theorem to predict how critically-ill patients respond to treatment, based on both heart rate data and blood pressure data collected by standard hospital monitoring devices. The non-equilibrium fluctuation dissipation theorem relates the response of a system to a perturbation to the fluctuations in the stationary state of the system. It is shown that the response of patients to a standard procedure performed on patients, the spontaneous breathing trial (SBT), can be predicted by the non-equilibrium fluctuation dissipation approach. We classify patients into different groups according to the patients' characteristics. For each patient group, we extend the fluctuation dissipation theorem to predict interactions between blood pressure and beat-to-beat dynamics of heart rate in response to a perturbation (SBT), We also extract the form of the perturbation function directly from the physiological data, which may help to reduce the prediction error. We note this method is not limited to the analysis of the heart rate dynamics, but also can be applied to analyze the response of other physiological signals to other clinical interventions.

  11. Stream Tables and Watershed Geomorphology Education.

    ERIC Educational Resources Information Center

    Lillquist, Karl D.; Kinner, Patricia W.

    2002-01-01

    Reviews copious stream tables and provides a watershed approach to stream table exercises. Results suggest that this approach to learning the concepts of fluvial geomorphology is effective. (Contains 39 references.) (DDR)

  12. 40 CFR Appendix - Tables to Part 132

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS WATER QUALITY GUIDANCE FOR THE GREAT... Tables to Part 132 Table 1—Acute Water Quality Criteria for Protection of Aquatic Life in Ambient Water... FR 35286, June 2, 2000] Table 2—Chronic Water Quality Criteria for Protection of Aquatic Life in...

  13. Commercial Buildings Energy Consumption Survey 2012 - Detailed Tables

    EIA Publications

    2016-01-01

    The 2012 CBECS consumption and expenditures detailed tables are comprised of Tables C1-C38, which cover overall electricity, natural gas, fuel oil and district heat consumption, and tables E1-E11, which disaggregate the same energy sources by end use (heating, cooling, lighting, etc.). All of the detailed tables contain extensive row categories of building characteristics.

  14. 40 CFR Appendix to Subpart Cc of... - Tables

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Tables Appendix to Subpart CC of Part... to Subpart CC of Part 63—Tables Table 1—Hazardous Air Pollutants Chemical name CAS No.a Benzene 71432... salts, esters, or derivatives. Table 2—Leak Definitions for Pumps and Valves Standard a Phase Leak...

  15. 40 CFR Appendix to Subpart Cc of... - Tables

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Tables Appendix to Subpart CC of Part... to Subpart CC of Part 63—Tables Table 1—Hazardous Air Pollutants Chemical name CAS No.a Benzene 71432... salts, esters, or derivatives. Table 2—Leak Definitions for Pumps and Valves Standard a Phase Leak...

  16. 40 CFR Appendix to Subpart Cc of... - Tables

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 11 2014-07-01 2014-07-01 false Tables Appendix to Subpart CC of Part... to Subpart CC of Part 63—Tables Table 1—Hazardous Air Pollutants Chemical name CAS No.a Benzene 71432... salts, esters, or derivatives. Table 2—Leak Definitions for Pumps and Valves Standard a Phase Leak...

  17. Synchrony in broadband fluctuation and the 2008 financial crisis.

    PubMed

    Lin, Der Chyan

    2013-01-01

    We propose phase-like characteristics in scale-free broadband processes and consider fluctuation synchrony based on the temporal signature of significant amplitude fluctuation. Using wavelet transform, successful captures of similar fluctuation pattern between such broadband processes are demonstrated. The application to the financial data leading to the 2008 financial crisis reveals the transition towards a qualitatively different dynamical regime with many equity price in fluctuation synchrony. Further analysis suggests an underlying scale free "price fluctuation network" with large clustering coefficient.

  18. Supplemental Figures, Tables, and Standard Error Tables for Student Financing of Undergraduate Education: 2007-08. Sticker, Net, and Out-of-Pocket Prices

    ERIC Educational Resources Information Center

    National Center for Education Statistics, 2010

    2010-01-01

    This paper presents the supplemental figures, tables, and standard error tables for the report "Student Financing of Undergraduate Education: 2007-08. Web Tables. NCES 2010-162." (Contains 6 figures and 10 tables.) [For the main report, see ED511828.

  19. Smoothed dissipative particle dynamics model for mesoscopic multiphase flows in the presence of thermal fluctuations

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

    Lei, Huan; Baker, Nathan A.; Wu, Lei

    2016-08-05

    Thermal fluctuations cause perturbations of fluid-fluid interfaces and highly nonlinear hydrodynamics in multiphase flows. In this work, we develop a novel multiphase smoothed dissipative particle dynamics model. This model accounts for both bulk hydrodynamics and interfacial fluctuations. Interfacial surface tension is modeled by imposing a pairwise force between SDPD particles. We show that the relationship between the model parameters and surface tension, previously derived under the assumption of zero thermal fluctuation, is accurate for fluid systems at low temperature but overestimates the surface tension for intermediate and large thermal fluctuations. To analyze the effect of thermal fluctuations on surface tension,more » we construct a coarse-grained Euler lattice model based on the mean field theory and derive a semi-analytical formula to directly relate the surface tension to model parameters for a wide range of temperatures and model resolutions. We demonstrate that the present method correctly models the dynamic processes, such as bubble coalescence and capillary spectra across the interface.« less

  20. Break-up dynamics of fluctuating liquid threads

    PubMed Central

    Petit, Julien; Rivière, David; Kellay, Hamid; Delville, Jean-Pierre

    2012-01-01

    The thinning dynamics of a liquid neck before break-up, as may happen when a drop detaches from a faucet or a capillary, follows different rules and dynamic scaling laws depending on the importance of inertia, viscous stresses, or capillary forces. If now the thinning neck reaches dimensions comparable to the thermally excited interfacial fluctuations, as for nanojet break-up or the fragmentation of thermally annealed nanowires, these fluctuations should play a dominant role according to recent theory and observations. Using near-critical interfaces, we here fully characterize the universal dynamics of this thermal fluctuation-dominated regime and demonstrate that the cross-over from the classical two-fluid pinch-off scenario of a liquid thread to the fluctuation-dominated regime occurs at a well-defined neck radius proportional to the thermal length scale. Investigating satellite drop formation, we also show that at the level of the cross-over between these two regimes it is more probable to produce monodisperse droplets because fluctuation-dominated pinch-off may allow the unique situation where satellite drop formation can be inhibited. Nonetheless, the interplay between the evolution of the neck profiles from the classical to the fluctuation-dominated regime and the satellites’ production remains to be clarified. PMID:23090994