Science.gov

Sample records for skew bridges

  1. Buffeting response of long-span cable-supported bridges under skew winds. Part 2: case study

    NASA Astrophysics Data System (ADS)

    Xu, Y. L.; Zhu, L. D.

    2005-03-01

    The finite-element-based framework for buffeting analysis of long-span cable-supported bridges under skew winds has been presented in Part 1 of this paper. The framework is now applied to the Tsing Ma Suspension Bridge in Hong Kong as a case study. The wind velocities and bridge responses measured by the Wind and Structural Health Monitoring System (WASHMS) of the bridge during Typhoon Sam in 1999 are first analyzed to find the skew wind characteristics surrounding the bridge, the modal damping ratios and acceleration responses of the bridge. The buffeting responses of the bridge under skew winds during Typhoon Sam are then computed using the wind characteristics and modal damping ratios measured from the field and the aerodynamic coefficients and flutter derivatives of the bridge deck and tower measured from the wind tunnel under skew winds. The computed acceleration responses of the bridge deck and cable are finally compared with the responses measured from the field. The comparison is found to be satisfactory in general and the case study forms a good practical demonstration for the verification of the proposed method for buffeting analysis of long-span cable-supported bridges under skew winds.

  2. Performance-based seismic assessment of skewed bridges with and without considering soil-structure interaction effects for various site classes

    NASA Astrophysics Data System (ADS)

    Ghotbi, Abdoulreza

    This study aims to investigate the behavior of skewed and straight highway overpass bridges both with and without taking into account the effects of Soil-Structure Interaction (SSI) due to near-fault ground motions. Both deterministic (i.e., pushover and nonlinear dynamic analyses) and probabilistic approaches were utilized. A set of response sensitivity analyses was performed considering various skew angles, column elements, and soil properties for bridge considered both as fixed-base and SSI models. It has been observed that as the skew angle increased, the bridge responded more severely to the ground motion. For instance, the deck rotation and shear-keys displacement increased with an increase in the skew angle. A modal pushover analysis was also performed in conjunction with the nonlinear dynamic analysis. It has been found that combining the bridge responses for various modes of vibration resulted in a relatively accurate seismic response compared to the nonlinear dynamic analysis while saving time and analysis cost, to a great extent. A probabilistic analysis was also performed considering record-to-record variability in ground motion, and a set of probabilistic seismic demand and fragility plots was generated. The effects of change in the skew angle and also SSI were studied to see various bridge responses. The damage probability increased especially with respect to deck rotation as the skew angle increased. The SSI had a decreasing effect on the overall response of the bridge with pile foundation.

  3. Performance-based seismic assessment of skewed bridges with and without considering soil-foundation interaction effects for various site classes

    NASA Astrophysics Data System (ADS)

    Ghotbi, Abdoul R.

    2014-09-01

    The seismic behavior of skewed bridges has not been well studied compared to straight bridges. Skewed bridges have shown extensive damage, especially due to deck rotation, shear keys failure, abutment unseating and column-bent drift. This research, therefore, aims to study the behavior of skewed and straight highway overpass bridges both with and without taking into account the effects of Soil-Structure Interaction (SSI) due to near-fault ground motions. Due to several sources of uncertainty associated with the ground motions, soil and structure, a probabilistic approach is needed. Thus, a probabilistic methodology similar to the one developed by the Pacific Earthquake Engineering Research Center (PEER) has been utilized to assess the probability of damage due to various levels of shaking using appropriate intensity measures with minimum dispersions. The probabilistic analyses were performed for various bridge configurations and site conditions, including sand ranging from loose to dense and clay ranging from soft to stiff, in order to evaluate the effects. The results proved a considerable susceptibility of skewed bridges to deck rotation and shear keys displacement. It was also found that SSI had a decreasing effect on the damage probability for various demands compared to the fixed-base model without including SSI. However, deck rotation for all types of the soil and also abutment unseating for very loose sand and soft clay showed an increase in damage probability compared to the fixed-base model. The damage probability for various demands has also been found to decrease with an increase of soil strength for both sandy and clayey sites. With respect to the variations in the skew angle, an increase in skew angle has had an increasing effect on the amplitude of the seismic response for various demands. Deck rotation has been very sensitive to the increase in the skew angle; therefore, as the skew angle increased, the deck rotation responded accordingly. Furthermore, abutment unseating showed an increasing trend due to an increase in skew angle for both fixed-base and SSI models.

  4. Bridges

    USGS Multimedia Gallery

    Bridges from top to bottom: Expressway Bridge, Liberty Memorial Bridge, Burlington Northern SantaFe Railway Bridge, and Interstate 94 Grant Marsh Bridge. Photo taken by USGS personnel on a Civil Air Patrol flight....

  5. Metric adjusted skew information

    E-print Network

    Frank Hansen

    2008-02-21

    We extend the concept of Wigner-Yanase-Dyson skew information to something we call ``metric adjusted skew information'' (of a state with respect to a conserved observable). This ``skew information'' is intended to be a non-negative quantity bounded by the variance (of an observable in a state) that vanishes for observables commuting with the state. We show that the skew information is a convex function on the manifold of states. It also satisfies other requirements, proposed by Wigner and Yanase, for an effective measure-of-information content of a state relative to a conserved observable. We establish a connection between the geometrical formulation of quantum statistics as proposed by Chentsov and Morozova and measures of quantum information as introduced by Wigner and Yanase and extended in this article. We show that the set of normalized Morozova-Chentsov functions describing the possible quantum statistics is a Bauer simplex and determine its extreme points. We determine a particularly simple skew information, the ``lambda-skew information,'' parametrized by a lambda in (0,1], and show that the convex cone this family generates coincides with the set of all metric adjusted skew informations. Key words: Skew information, convexity, monotone metric, Morozova-Chentsov function, lambda-skew information.

  6. Quantum skew divergence

    SciTech Connect

    Audenaert, Koenraad M. R.

    2014-11-15

    In this paper, we study the quantum generalisation of the skew divergence, which is a dissimilarity measure between distributions introduced by Lee in the context of natural language processing. We provide an in-depth study of the quantum skew divergence, including its relation to other state distinguishability measures. Finally, we present a number of important applications: new continuity inequalities for the quantum Jensen-Shannon divergence and the Holevo information, and a new and short proof of Bravyi's Small Incremental Mixing conjecture.

  7. Quantum skew divergence

    NASA Astrophysics Data System (ADS)

    Audenaert, Koenraad M. R.

    2014-11-01

    In this paper, we study the quantum generalisation of the skew divergence, which is a dissimilarity measure between distributions introduced by Lee in the context of natural language processing. We provide an in-depth study of the quantum skew divergence, including its relation to other state distinguishability measures. Finally, we present a number of important applications: new continuity inequalities for the quantum Jensen-Shannon divergence and the Holevo information, and a new and short proof of Bravyi's Small Incremental Mixing conjecture.

  8. 12. Underside of Skew SpanHot Metal system on right, toward ...

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

    12. Underside of Skew Span-Hot Metal system on right, toward Rocker Bent. - Monongahela Connecting Railroad Company, Hot Metal Bridge, Spanning Monongahela River at mile post 3.1, Pittsburgh, Allegheny County, PA

  9. CYLINDRIC SKEW SCHUR FUNCTIONS PETER MCNAMARA

    E-print Network

    McNamara, Peter

    CYLINDRIC SKEW SCHUR FUNCTIONS PETER MCNAMARA Abstract. Cylindric skew Schur functions, which explaining these motivations, we study cylindric skew Schur functions from the point of view of Schur-Fontanine and W. Fulton, thus giving an expansion of an arbitrary cylindric skew Schur function in terms of skew

  10. Einstein manifolds with skew torsion

    E-print Network

    Ilka Agricola; Ana Cristina Ferreira

    2013-02-15

    This paper is devoted to the first systematic investigation of manifolds that are Einstein for a connection with skew symmetric torsion. We derive the Einstein equation from a variational principle and prove that, for parallel torsion, any Einstein manifold with skew torsion has constant scalar curvature; and if it is complete of positive scalar curvature, it is necessarily compact and it has finite first fundamental group. The longest part of the paper is devoted to the systematic construction of large families of examples. We discuss when a Riemannian Einstein manifold can be Einstein with skew torsion. We give examples of almost Hermitian, almost metric contact, and G2 manifolds that are Einstein with skew torsion. For example, we prove that any Einstein-Sasaki manifold and any 7-dimensional 3-Sasakian manifolds admit deformations into an Einstein metric with parallel skew torsion.

  11. Skew resisting hydrodynamic seal

    DOEpatents

    Conroy, William T. (Pearland, TX); Dietle, Lannie L. (Sugar Land, TX); Gobeli, Jeffrey D. (Houston, TX); Kalsi, Manmohan S. (Houston, TX)

    2001-01-01

    A novel hydrodynamically lubricated compression type rotary seal that is suitable for lubricant retention and environmental exclusion. Particularly, the seal geometry ensures constraint of a hydrodynamic seal in a manner preventing skew-induced wear and provides adequate room within the seal gland to accommodate thermal expansion. The seal accommodates large as-manufactured variations in the coefficient of thermal expansion of the sealing material, provides a relatively stiff integral spring effect to minimize pressure-induced shuttling of the seal within the gland, and also maintains interfacial contact pressure within the dynamic sealing interface in an optimum range for efficient hydrodynamic lubrication and environment exclusion. The seal geometry also provides for complete support about the circumference of the seal to receive environmental pressure, as compared the interrupted character of seal support set forth in U.S. Pat. Nos. 5,873,576 and 6,036,192 and provides a hydrodynamic seal which is suitable for use with non-Newtonian lubricants.

  12. Rizkalla, S., and Tadros, G., "FRP for Prestressing of Concrete Bridges in Canada,"Page 1 FRP for Prestressing of Concrete Bridges in Canada

    E-print Network

    undertaken before the final design of the two bridges. The first bridge is a 75 ft. (23.85 m) span skew. Design considerations and details of the safety features used for each bridge are provided. The paper. SIGNIFICANCE OF RESEARCH The experience gained by design, prestressing of bridge girders and construction

  13. Factor Analysis for Skewed Data and Skew-Normal Maximum Likelihood Factor Analysis 

    E-print Network

    Gaucher, Beverly Jane

    2013-04-04

    This research explores factor analysis applied to data from skewed distributions for the general skew model, the selection-elliptical model, the selection-normal model, the skew-elliptical model and the skew-normal model for finite sample sizes...

  14. HOT METAL BRIDGE (NOTE: BUILDERS: JONES AND LAUGHLIN STEEL CA. ...

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

    HOT METAL BRIDGE (NOTE: BUILDERS: JONES AND LAUGHLIN STEEL CA. 1890), SOUTH PORTAL. THREE PIN CONNECTED CAMELBACK TRUSS SPANS, ONE SKEWED THROUGH TRUSS SPAN ON NORTH SIDE TRUSS BRIDGE, EAST OF HOT METAL BRIDGE BUILT BY AMERICAN BRIDGE COMPANY CA. 1910. (RIVETED MULTI-SPAN TRUSS). - Jones & Laughlin Steel Corporation, Pittsburgh Works, Morgan Billet Mill Engine, 550 feet north of East Carson Street, opposite South Twenty-seventh Street, Pittsburgh, Allegheny County, PA

  15. Kinematic correction for roller skewing

    NASA Technical Reports Server (NTRS)

    Savage, M.; Loewenthal, S. H.

    1980-01-01

    A theory of kinematic stabilization of rolling cylinders is developed for high-speed cylindrical roller bearings. This stabilization requires race and roller crowning to product changes in the rolling geometry as the roller shifts axially. These changes put a reverse skew in the rolling elements by changing the rolling taper. Twelve basic possible bearing modifications are identified in this paper. Four have single transverse convex curvature in the rollers while eight have rollers with compound transverse curvature composed of a central cylindrical band of constant radius surrounded by symmetric bands with both slope and transverse curvature.

  16. Roller skewing measurements in cylindrical roller bearings

    NASA Technical Reports Server (NTRS)

    Nypan, L. J.

    1981-01-01

    Measurements of roller skewing in a 118 mm bore roller bearing operating at shaft speeds to 12,000 rpm are reported. High speed motion pictures of a modified roller were taken through a derotation prism to record skewing as the roller moved through loaded and unloaded regions of the bearing. Subsequent frame by frame measurement of the photographic film provided information on roller skewing. Radial and tangential skew amplitudes of 0.4 to 0.5 degrees were observed with 0.5 degree misalignment.

  17. Portfolio optimization with skewness and kurtosis

    NASA Astrophysics Data System (ADS)

    Lam, Weng Hoe; Jaaman, Saiful Hafizah Hj.; Isa, Zaidi

    2013-04-01

    Mean and variance of return distributions are two important parameters of the mean-variance model in portfolio optimization. However, the mean-variance model will become inadequate if the returns of assets are not normally distributed. Therefore, higher moments such as skewness and kurtosis cannot be ignored. Risk averse investors prefer portfolios with high skewness and low kurtosis so that the probability of getting negative rates of return will be reduced. The objective of this study is to compare the portfolio compositions as well as performances between the mean-variance model and mean-variance-skewness-kurtosis model by using the polynomial goal programming approach. The results show that the incorporation of skewness and kurtosis will change the optimal portfolio compositions. The mean-variance-skewness-kurtosis model outperforms the mean-variance model because the mean-variance-skewness-kurtosis model takes skewness and kurtosis into consideration. Therefore, the mean-variance-skewness-kurtosis model is more appropriate for the investors of Malaysia in portfolio optimization.

  18. Skew-Flavored Dark Matter

    E-print Network

    Agrawal, Prateek; Fortes, Elaine C F S; Kilic, Can

    2015-01-01

    We explore a novel flavor structure in the interactions of dark matter with the Standard Model. We consider theories in which both the dark matter candidate, and the particles that mediate its interactions with the Standard Model fields, carry flavor quantum numbers. The interactions are skewed in flavor space, so that a dark matter particle does not directly couple to the Standard Model matter fields of the same flavor, but only to the other two flavors. This framework respects Minimal Flavor Violation, and is therefore naturally consistent with flavor constraints. We study the phenomenology of a benchmark model in which dark matter couples to right-handed charged leptons. In large regions of parameter space the dark matter can emerge as a thermal relic, while remaining consistent with the constraints from direct and indirect detection. The collider signatures of this scenario include events with multiple leptons and missing energy. These events exhibit a characteristic flavor pattern that may allow this cla...

  19. Reproductive skew in the polygynandrous acorn woodpecker

    PubMed Central

    Haydock, Joseph; Koenig, Walter D.

    2002-01-01

    Reproductive skew models, which focus on the degree to which reproduction is shared equally (low skew) or monopolized by a single individual (high skew) within groups, have been heralded as providing a general unifying framework for understanding the factors determining social evolution. Here, we test the ability of optimal skew, or “transactional,” models, which predict the level of skew necessary to promote stable associations of dominants and subordinates, rather than independent breeding, to predict reproductive partitioning in the acorn woodpecker (Melanerpes formicivorus). This species provides a key test case because only a few vertebrates exhibit polygynandry (multiple breeders of both sexes within a group). Contrary to the predictions of the models, joint-nesting females share reproduction more equitably than expected, apparently because egg destruction and the inability of females to defend their eggs from cobreeders eliminate any possibility for one female to control reproduction. For males, however, reproductive skew is high, with the most successful male siring over three times as many young as the next most successful male. Although this result is consistent with optimal skew models, other aspects of male behavior are not; in particular, the reproductively most successful male frequently switches between nests produced by the same set of cobreeders, and we were unable to detect any phenotypic correlate of success. These results are consistent with an alternative null model in which cobreeder males have equal chance of paternity, but paternity of offspring within broods is nonindependent as a consequence of female, rather than male, control. PMID:11997473

  20. Decomposing data sets into skewness modes

    E-print Network

    Rubén A. Pasmanter; Frank M. Selten

    2009-08-24

    We derive the nonlinear equations satisfied by the coefficients of linear combinations that maximize their skewness when their variance is constrained to take a specific value. In order to numerically solve these nonlinear equations we develop a gradient-type flow that preserves the constraint. In combination with the Karhunen-Lo\\`eve decomposition this leads to a set of orthogonal modes with maximal skewness. For illustration purposes we apply these techniques to atmospheric data; in this case the maximal-skewness modes correspond to strongly localized atmospheric flows. We show how these ideas can be extended, for example to maximal-flatness modes.

  1. Skew-Flavored Dark Matter

    E-print Network

    Prateek Agrawal; Zackaria Chacko; Elaine C. F. S. Fortes; Can Kilic

    2015-11-19

    We explore a novel flavor structure in the interactions of dark matter with the Standard Model. We consider theories in which both the dark matter candidate, and the particles that mediate its interactions with the Standard Model fields, carry flavor quantum numbers. The interactions are skewed in flavor space, so that a dark matter particle does not directly couple to the Standard Model matter fields of the same flavor, but only to the other two flavors. This framework respects Minimal Flavor Violation, and is therefore naturally consistent with flavor constraints. We study the phenomenology of a benchmark model in which dark matter couples to right-handed charged leptons. In large regions of parameter space the dark matter can emerge as a thermal relic, while remaining consistent with the constraints from direct and indirect detection. The collider signatures of this scenario include events with multiple leptons and missing energy. These events exhibit a characteristic flavor pattern that may allow this class of models to be distinguished from other theories of dark matter.

  2. Bridge permeameter

    DOEpatents

    Graf, Darin C. (Edgewood, NM); Warpinski, Norman R. (Albuquerque, NM)

    1996-01-01

    A system for single-phase, steady-state permeability measurements of porous rock utilizes a fluid bridge arrangement analogous to a Wheatstone bridge. The arms of the bridge contain the sample and calibrated flow resistors.

  3. Myocardial Bridge

    MedlinePLUS

    ... Sudden Cardiac Arrest Valve Disease Vulnerable Plaque Myocardial Bridge | Share Related terms: myocardium, coronary arteries, myocardial ischemia ... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart ...

  4. High reproductive skew in tropical hover wasps.

    PubMed Central

    Sumner, Seirian; Casiraghi, Maurizio; Foster, William; Field, Jeremy

    2002-01-01

    A plethora of recent models examines how genetic and environmental factors might influence partitioning of reproduction ('skew') in animal societies, but empirical data are sparse. We used three microsatellite loci to estimate skew on 13 nests of the Malaysian hover wasp, Liostenogaster flavolineata. Groups are small in L. flavolineata (1-10 females) and all females are capable of mating and laying eggs. Despite considerable variation between nests in parameters expected to influence skew, skew was uniformly high. On 11 of the 13 nests, all female eggs had been laid by a single dominant female. A second female had laid one to two out of 5-10 eggs respectively on the two remaining nests. A likelihood analysis suggested that on average, 90% of the male eggs had also been laid by the dominant. The slightly lower skew among male eggs might reflect the lower average relatedness of subordinates to male versus female offspring of the dominant. We suggest that high skew in L. flavolineata may result from strong ecological constraints and a relatively high probability that a subordinate will eventually inherit the dominant, egg-laying position. PMID:11798434

  5. Defining surfaces for skewed, highly variable data

    USGS Publications Warehouse

    Helsel, D.R.; Ryker, S.J.

    2002-01-01

    Skewness of environmental data is often caused by more than simply a handful of outliers in an otherwise normal distribution. Statistical procedures for such datasets must be sufficiently robust to deal with distributions that are strongly non-normal, containing both a large proportion of outliers and a skewed main body of data. In the field of water quality, skewness is commonly associated with large variation over short distances. Spatial analysis of such data generally requires either considerable effort at modeling or the use of robust procedures not strongly affected by skewness and local variability. Using a skewed dataset of 675 nitrate measurements in ground water, commonly used methods for defining a surface (least-squares regression and kriging) are compared to a more robust method (loess). Three choices are critical in defining a surface: (i) is the surface to be a central mean or median surface? (ii) is either a well-fitting transformation or a robust and scale-independent measure of center used? (iii) does local spatial autocorrelation assist in or detract from addressing objectives? Published in 2002 by John Wiley & Sons, Ltd.

  6. Modular classes of skew algebroid relations

    E-print Network

    Grabowski, Janusz

    2011-01-01

    Skew algebroid is a natural generalization of the concept of Lie algebroid. In this paper, for a skew algebroid E, its modular class mod(E) is defined in the classical as well as in the supergeometric formulation. It is proved that there is a homogeneous nowhere-vanishing 1-density on E* which is invariant with respect to all Hamiltonian vector fields if and only if E is modular, i.e. mod(E)=0. Further, relative modular class of a subalgebroid is introduced and studied together with its application to holonomy, as well as modular class of a skew algebroid relation. These notions provide, in particular, a unified approach to the concepts of a modular class of a Lie algebroid morphism and that of a Poisson map.

  7. Modular classes of skew algebroid relations

    E-print Network

    Janusz Grabowski

    2011-08-11

    Skew algebroid is a natural generalization of the concept of Lie algebroid. In this paper, for a skew algebroid E, its modular class mod(E) is defined in the classical as well as in the supergeometric formulation. It is proved that there is a homogeneous nowhere-vanishing 1-density on E* which is invariant with respect to all Hamiltonian vector fields if and only if E is modular, i.e. mod(E)=0. Further, relative modular class of a subalgebroid is introduced and studied together with its application to holonomy, as well as modular class of a skew algebroid relation. These notions provide, in particular, a unified approach to the concepts of a modular class of a Lie algebroid morphism and that of a Poisson map.

  8. Skewness and Kurtosis in Statistical Kinetics

    NASA Astrophysics Data System (ADS)

    Barato, Andre C.; Seifert, Udo

    2015-10-01

    We obtain lower and upper bounds on the skewness and kurtosis associated with the cycle completion time of unicyclic enzymatic reaction schemes. Analogous to a well-known lower bound on the randomness parameter, the lower bounds on skewness and kurtosis are related to the number of intermediate states in the underlying chemical reaction network. Our results demonstrate that evaluating these higher order moments with single molecule data can lead to information about the enzymatic scheme that is not contained in the randomness parameter.

  9. Skew chicane based betatron eigenmode exchange module

    DOEpatents

    Douglas, David (Yorktown, VA)

    2010-12-28

    A skewed chicane eigenmode exchange module (SCEEM) that combines in a single beamline segment the separate functionalities of a skew quad eigenmode exchange module and a magnetic chicane. This module allows the exchange of independent betatron eigenmodes, alters electron beam orbit geometry, and provides longitudinal parameter control with dispersion management in a single beamline segment with stable betatron behavior. It thus reduces the spatial requirements for multiple beam dynamic functions, reduces required component counts and thus reduces costs, and allows the use of more compact accelerator configurations than prior art design methods.

  10. Biased Estimations of Variance and Skewness

    SciTech Connect

    Hui, L. ); Gaztanaga, E. , Institut d'Estudis Espacials de Catalunya, Edf. Nexus-104-c/ Gran Capita 2-4, 08034, Barcelona )

    1999-07-01

    Nonlinear combinations of direct observables are often used to estimate quantities of theoretical interest. Without sufficient caution, this could lead to biased estimations. An example of great interest is the skewness S[sub 3] of the galaxy distribution, defined as the ratio of the third moment [bar [xi

  11. Bridge permeameter

    DOEpatents

    Graf, D.C.; Warpinski, N.R.

    1996-08-13

    A system is described for single-phase, steady-state permeability measurements of porous rock which utilizes a fluid bridge arrangement analogous to a Wheatstone bridge. The arms of the bridge contain the sample and calibrated flow resistors. 8 figs.

  12. Safer Bridges

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Safer bridges are among a number of spinoff benefits from NASA procedures for testing 'cfracture toughness" of a structural part, meaning its ability to -siscracktsh at might cause failure. The New River Bridge in West Virginia, shown under construction, is the world's largest single span bridge. U.S. Steel fracture toughness requirements for such bridges include NASA-developed test procedures. Bridge materials and other metal structures may develop flaws during their service lifetimes. Such flaws can affect the structural integrity of the part. Thus, it is important to know the "fracture toughness" of a structural part, or its ability to resist cracks. NASA has long experience in developing fracture toughness tests for aerospace hardware. Since 1960, NASA-Lewis has worked closely with the American Society for Testing & Materials. Lewis and NASA-funded industrial contractors have made many important contributions to test procedures, now recommended by ASTM, for measuring fracture toughness.

  13. Inferring climate variability from skewed proxy records

    NASA Astrophysics Data System (ADS)

    Emile-Geay, J.; Tingley, M.

    2013-12-01

    Many paleoclimate analyses assume a linear relationship between the proxy and the target climate variable, and that both the climate quantity and the errors follow normal distributions. An ever-increasing number of proxy records, however, are better modeled using distributions that are heavy-tailed, skewed, or otherwise non-normal, on account of the proxies reflecting non-normally distributed climate variables, or having non-linear relationships with a normally distributed climate variable. The analysis of such proxies requires a different set of tools, and this work serves as a cautionary tale on the danger of making conclusions about the underlying climate from applications of classic statistical procedures to heavily skewed proxy records. Inspired by runoff proxies, we consider an idealized proxy characterized by a nonlinear, thresholded relationship with climate, and describe three approaches to using such a record to infer past climate: (i) applying standard methods commonly used in the paleoclimate literature, without considering the non-linearities inherent to the proxy record; (ii) applying a power transform prior to using these standard methods; (iii) constructing a Bayesian model to invert the mechanistic relationship between the climate and the proxy. We find that neglecting the skewness in the proxy leads to erroneous conclusions and often exaggerates changes in climate variability between different time intervals. In contrast, an explicit treatment of the skewness, using either power transforms or a Bayesian inversion of the mechanistic model for the proxy, yields significantly better estimates of past climate variations. We apply these insights in two paleoclimate settings: (1) a classical sedimentary record from Laguna Pallcacocha, Ecuador (Moy et al., 2002). Our results agree with the qualitative aspects of previous analyses of this record, but quantitative departures are evident and hold implications for how such records are interpreted, and compared to other proxy records. (2) a multiproxy reconstruction of temperature over the Common Era (Mann et al., 2009), where we find that about one third of the records display significant departures from normality. Accordingly, accounting for skewness in proxy predictors has a notable influence on both reconstructed global mean and spatial patterns of temperature change. Inferring climate variability from skewed proxy records thus requires cares, but can be done with relatively simple tools. References - Mann, M. E., Z. Zhang, S. Rutherford, R. S. Bradley, M. K. Hughes, D. Shindell, C. Ammann, G. Faluvegi, and F. Ni (2009), Global signatures and dynamical origins of the little ice age and medieval climate anomaly, Science, 326(5957), 1256-1260, doi:10.1126/science.1177303. - Moy, C., G. Seltzer, D. Rodbell, and D. Anderson (2002), Variability of El Niño/Southern Oscillation activ- ity at millennial timescales during the Holocene epoch, Nature, 420(6912), 162-165.

  14. Biased Estimations of Variance and Skewness

    NASA Astrophysics Data System (ADS)

    Hui, Lam; Gaztañaga, Enrique

    1999-07-01

    Nonlinear combinations of direct observables are often used to estimate quantities of theoretical interest. Without sufficient caution, this could lead to biased estimations. An example of great interest is the skewness S3 of the galaxy distribution, defined as the ratio of the third moment ?¯3 and the variance squared ?¯22 smoothed at some scale R. Suppose one is given unbiased estimators for ?¯3 and ?¯22, respectively; taking a ratio of the two does not necessarily result in an unbiased estimator of S3. Exactly such an estimation bias (distinguished from the galaxy bias) affects most existing measurements of S3 from galaxy surveys. Furthermore, common estimators for ?¯3 and ?¯2 suffer also from this kind of estimation bias themselves because of a division by the estimated mean counts in cell. In the case of ?¯2, the bias is equivalent to what is commonly known as the integral constraint. We present a unifying treatment allowing all these estimation biases to be calculated analytically. These estimation biases are in general negative, and decrease in significance as the survey volume increases, for a given smoothing scale. We present a preliminary reanalysis of some existing measurements of the variance and skewness (from the APM, CfA, SSRS, and IRAS) and show that most of the well-known systematic discrepancies between surveys with similar selection criteria, but different sizes, can be attributed to the volume-dependent estimation biases. This affects the inference of the galaxy bias(es) from these surveys. Our methodology can be adapted to measurements of the variance and skewness of, for instance, the transmission distribution in quasar spectra and the convergence distribution in weak-lensing maps. We discuss generalizations to N>3, suggest methods to reduce the estimation bias, and point out other examples in large-scale structure studies that might suffer from this type of a nonlinear estimation bias.

  15. Associative skew clock routing for difficult instances 

    E-print Network

    Kim, Min-seok

    2006-08-16

    stream_source_info etd-tamu-2006A-CEEN-Kim.pdf.txt stream_content_type text/plain stream_size 30458 Content-Encoding ISO-8859-1 stream_name etd-tamu-2006A-CEEN-Kim.pdf.txt Content-Type text/plain; charset=ISO-8859...-1 ASSOCIATIVE SKEW CLOCK ROUTING FOR DIFFICULT INSTANCES A Thesis by MIN-SEOK KIM Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May 2006 Major Subject...

  16. Skew quad compensation for SPEAR minibeta optics

    SciTech Connect

    Wille, K.

    1984-06-01

    With the new minibeta insertion for SPEAR the betatron coupling and the perturbations of beam optics caused by the solenoid field of the MARK III detector can't be compensated by the simple coils used so far. Therefore another scheme with four skew quads arranged in two families has been chosen. Even though this scheme doesn't compensate the effect of the solenoid on the beam completely, the residual emittance coupling is much less than 1% which should be sufficient under all running conditions. The major advantage of this concept is its simplicity.

  17. Temperature-Compensated Clock Skew Adjustment

    PubMed Central

    Castillo-Secilla, Jose María; Palomares, Jose Manuel; Olivares, Joaquín

    2013-01-01

    This work analyzes several drift compensation mechanisms in wireless sensor networks (WSN). Temperature is an environmental factor that greatly affects oscillators shipped in every WSN mote. This behavior creates the need of improving drift compensation mechanisms in synchronization protocols. Using the Flooding Time Synchronization Protocol (FTSP), this work demonstrates that crystal oscillators are affected by temperature variations. Thus, the influence of temperature provokes a low performance of FTSP in changing conditions of temperature. This article proposes an innovative correction factor that minimizes the impact of temperature in the clock skew. By means of this factor, two new mechanisms are proposed in this paper: the Adjusted Temperature (AT) and the Advanced Adjusted Temperature (A2T). These mechanisms have been combined with FTSP to produce AT-FTSP and A2T-FTSP Both have been tested in a network of TelosB motes running TinyOS. Results show that both AT-FTSP and A2T-FTSP improve the average synchronization errors compared to FTSP and other temperature-compensated protocols (Environment-Aware Clock Skew Estimation and Synchronization for WSN (EACS) and Temperature Compensated Time Synchronization (TCTS)). PMID:23966192

  18. Modelling Scalar Skewness in Cloudy Boundary Layers

    NASA Astrophysics Data System (ADS)

    Mironov, Dmitrii; Machulskaya, Ekaterina; Naumann, Ann Kristin; Seifert, Axel; Mellado, Juan Pedro

    2015-04-01

    Following the pioneering work of Sommeria and Deardorff (1977), statistical cloud schemes are widely used in numerical weather prediction (NWP) and climate models to parameterize the effect of shallow clouds on turbulent mixing and radiation fluxes. Statistical cloud schemes compute the cloud fraction, the amount of cloud condensate and the effect clouds on the buoyancy flux in a given atmospheric-model grid box. This is done with due regard for the sub-grid scale (SGS) fluctuations of temperature and humidity (and possibly the vertical velocity), thus providing an important coupling between cloudiness and the SGS mixing processes. The shape of the PDF of fluctuating fields is assumed, whereas the PDF moments should be provided to the cloud scheme as an input. For non-precipitation clouds, the mixing schemes are usually formulated in terms of quasi-conservative variable, e.g. the liquid (total) water potential temperature and the total water specific humidity. Then, the cloud schemes are conveniently cast in terms of the linearized saturation deficit, referred to as the "s" variable (Mellor 1977), that accounts for the combined effect of the two scalars. If a simple two-parameter single-Gaussian PDF is used, the only "turbulence" parameter to be provided to the cloud scheme is the variance of s. The single-Gaussian PDF ignores the skewed nature of SGS motions and fails to describe many important regimes, e.g. shallow cumuli. A number of more flexible skewed PDFs have been proposed to date. A three-parameter PDF, based on a double-Gaussian distribution and diagnostic relations between some PDF parameters derived from LES and observational data (Naumann et al. 2013), appears to be a good compromise between physical realism and computational economy. A crucial point is that the cloud schemes using non-Gaussian PDFs require the scalar skewness as an input. Using rather mild non-restrictive assumptions, we develop a transport equation for the s-variable triple correlation. That equation contains three terms that require closure. A simple relaxation approximation in terms of the turbulence time (length) scale is used for the dissipation term. The third-order and the fourth-order scalar-velocity correlations are parameterized using an advanced advection-diffusion formulation and a generalized Millionschikov hypothesis (Mironov et al. 1999, Gryanik et al. 2005). These formulations satisfy both the Gaussian limit and, importantly, the limit of strong skewness. The equation for the s triple correlation is coupled to the turbulence kinetic energy (TKE) - scalar variance mixing scheme (Machulskaya and Mironov 2013), where not only the TKE but also the scalar variances and covariance are computed from the prognostic transport equations with due regard for the third-order transport. The coupled scheme is tested through single-column numerical experiments. Results compare favourably with large-eddy simulation data from well-documented shallow cloud cases. Some details of the implementation of the s-skewness formulation into NWP models are discussed.

  19. Bridging Anticoagulation

    MedlinePLUS

    ... practical approach . Blood . 2011 ; 117 : 5044 – 5049 . FREE Full Text Spyropoulos AC . Bridging therapy and oral anticoagulation: current ... doi: 10.1161/CIRCULATIONAHA.111.084517 Extract Free » Full Text Free PDF Free Classifications Cardiology Patient Page Services ...

  20. Liquid Bridge

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Crystal Growth in magnetic fields, a float-zone sample, the surface tension of the melt keeps the sample suspended between the sample rods in the furnace forming an actual liquid bridge. Principal Investigator: Dr. Frank Szofran

  1. Learning a Novel Pattern through Balanced and Skewed Input

    ERIC Educational Resources Information Center

    McDonough, Kim; Trofimovich, Pavel

    2013-01-01

    This study compared the effectiveness of balanced and skewed input at facilitating the acquisition of the transitive construction in Esperanto, characterized by the accusative suffix "-n" and variable word order (SVO, OVS). Thai university students (N = 98) listened to 24 sentences under skewed (one noun with high token frequency) or…

  2. Polynomial Combinatorial Algorithms for Skew-bisubmodular Function Minimization

    E-print Network

    Kawahigashi, Yasuyuki

    RIMS-1837 Polynomial Combinatorial Algorithms for Skew-bisubmodular Function Minimization By Satoru, Kyoto, Japan #12;Polynomial Combinatorial Algorithms for Skew-bisubmodular Function Minimization Satoru for bisubmodular function minimization by Fujishige and Iwata [9] and McCormick and Fujishige [21], which are built

  3. EXPLOSION POINTS IN SKEW MAPS Anne Stefanie Costolanski

    E-print Network

    Sander, Evelyn

    EXPLOSION POINTS IN SKEW MAPS by Anne Stefanie Costolanski A Thesis Submitted to the Graduate: Summer Semester 2007 George Mason University Fairfax, VA #12;Explosion Points in Skew Maps A thesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 2.7 Crises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 2.8 Explosions

  4. ON THE SPECTRUM OF SKEW-SHIFT SCHRODINGER HELGE KRUGER

    E-print Network

    Krueger, Helge

    ON THE SPECTRUM OF SKEW-SHIFT SCHR¨ODINGER OPERATORS HELGE KR¨UGER Abstract. I prove that the spectrum of a skew-shift Schr¨odinger operator contains larges interval in the semi-classical regime-classical regime, that is for h > 0 sufficiently small, I will show that the spectrum of the operator Hh contains

  5. Testing for nonzero skew in maximum discharge runoff data

    NASA Astrophysics Data System (ADS)

    Whitley, Robert; Hromadka, T. V.

    1993-02-01

    Water Resource Council Bulletin 17B (Interagency Advisory Committee on Water Data, 1982) recommends finding T-year flood values by fitting stream gauge data with a log Pearson III distribution. A problem arising in using this method is that, as is well known, the estimator for the skew of this distribution is highly variable and the computed T-year values are sensitive to the value of skew used. The variability in estimating the skew is studied in this note by computing operating characteristic curves which display the probability that a sample from a site with a nonzero skew will actually fall in a specific interval. In rough summary it is not usually possible to reject, at a high level of significance the hypothesis that the skew at a site is zero by using only the data available for that site.

  6. Cracked shells under skew-symmetric loading

    NASA Technical Reports Server (NTRS)

    Lelale, F.

    1982-01-01

    A shell containing a through crack in one of the principal planes of curvature and under general skew-symmetric loading is considered. By employing a Reissner type shell theory which takes into account the effect of transverse shear strains, all boundary conditions on the crack surfaces are satisfied separately. Consequently, unlike those obtained from the classical shell theory, the angular distributions of the stress components around the crack tips are shown to be identical to the distributions obtained from the plane and antiplane elasticity solutions. Extensive results are given for axially and circumferentially cracked cylindrical shells, spherical shells, and toroidal shells under uniform inplane shearing, out of plane shearing, and torsion. The effect of orthotropy on the results is also studied.

  7. BRIDGE Summary Minutes BRIDGE Group Meeting

    E-print Network

    BRIDGE Summary Minutes 01.17.12 1 BRIDGE Group Meeting Date: 01.17.12 Agenda 1. CAT Tag Process 2 a schedule conflict and would be introduced at the March BRIDGE meeting. He encouraged BRIDGE members moved under his direction. The group has started an overnight report (which BRIDGE members can sign up

  8. Investigating the Investigative Task: Testing for Skewness--An Investigation of Different Test Statistics and Their Power to Detect Skewness

    ERIC Educational Resources Information Center

    Tabor, Josh

    2010-01-01

    On the 2009 AP[c] Statistics Exam, students were asked to create a statistic to measure skewness in a distribution. This paper explores several of the most popular student responses and evaluates which statistic performs best when sampling from various skewed populations. (Contains 8 figures, 3 tables, and 4 footnotes.)

  9. Female reproductive synchrony predicts skewed paternity across primates

    PubMed Central

    Nunn, Charles L.; Schülke, Oliver

    2008-01-01

    Recent studies have uncovered remarkable variation in paternity within primate groups. To date, however, we lack a general understanding of the factors that drive variation in paternity skew among primate groups and across species. Our study focused on hypotheses from reproductive skew theory involving limited control and the use of paternity “concessions” by investigating how paternity covaries with the number of males, female estrous synchrony, and rates of extragroup paternity. In multivariate and phylogenetically controlled analyses of data from 27 studies on 19 species, we found strong support for a limited control skew model, with reproductive skew within groups declining as female reproductive synchrony and the number of males per group increase. Of these 2 variables, female reproductive synchrony explained more of the variation in paternity distributions. To test whether dominant males provide incentives to subordinates to resist matings by extragroup males, that is, whether dominants make concessions of paternity, we derived a novel prediction that skew is lower within groups when threat from outside the group exists. This prediction was not supported as a primary factor underlying patterns of reproductive skew among primate species. However, our approach revealed that if concessions occur in primates, they are most likely when female synchrony is low, as these conditions provide alpha male control of paternity that is assumed by concessions models. Collectively, our analyses demonstrate that aspects of male reproductive competition are the primary drivers of reproductive skew in primates. PMID:19018288

  10. Bridged graphite oxide materials

    NASA Technical Reports Server (NTRS)

    Herrera-Alonso, Margarita (Inventor); McAllister, Michael J. (Inventor); Aksay, Ilhan A. (Inventor); Prud'homme, Robert K. (Inventor)

    2010-01-01

    Bridged graphite oxide material comprising graphite sheets bridged by at least one diamine bridging group. The bridged graphite oxide material may be incorporated in polymer composites or used in adsorption media.

  11. The Affective Impact of Financial Skewness on Neural Activity and Choice

    PubMed Central

    Wu, Charlene C.; Bossaerts, Peter; Knutson, Brian

    2011-01-01

    Few finance theories consider the influence of “skewness” (or large and asymmetric but unlikely outcomes) on financial choice. We investigated the impact of skewed gambles on subjects' neural activity, self-reported affective responses, and subsequent preferences using functional magnetic resonance imaging (FMRI). Neurally, skewed gambles elicited more anterior insula activation than symmetric gambles equated for expected value and variance, and positively skewed gambles also specifically elicited more nucleus accumbens (NAcc) activation than negatively skewed gambles. Affectively, positively skewed gambles elicited more positive arousal and negatively skewed gambles elicited more negative arousal than symmetric gambles equated for expected value and variance. Subjects also preferred positively skewed gambles more, but negatively skewed gambles less than symmetric gambles of equal expected value. Individual differences in both NAcc activity and positive arousal predicted preferences for positively skewed gambles. These findings support an anticipatory affect account in which statistical properties of gambles—including skewness—can influence neural activity, affective responses, and ultimately, choice. PMID:21347239

  12. The Bridge.

    ERIC Educational Resources Information Center

    Strunck, Ted

    1995-01-01

    A teacher at Upland Hills School (Royal Oaks, Michigan) describes how he and groups of seventh and eighth graders built a 175-foot bridge across a gully between the school and an outdoor environmental education area. Students received basic design and engineering instruction at a nearby university, and parents and community provided support and…

  13. Multiple linear regression estimators with skew normal errors

    NASA Astrophysics Data System (ADS)

    Alhamide, A. A.; Ibrahim, K.; Alodat, M. T.

    2015-09-01

    The idea of skew normal distribution is suitable to be used for the analysis of data which is skewed. The purpose of this paper is to study the estimation of the regression parameters under the extended multivariate skew normal errors. The estimators for the regression parameters found based on the maximum likelihood method are derived. A simulation study is carried out to investigate the performance of the estimators derived and the standard errors associate with the respective parameters estimates are found to be quite small.

  14. Numerical simulation of the Langevin equation for skewed turbulence

    SciTech Connect

    Ermak, D. L.; Nasstrom, J. S.

    1994-12-01

    In this paper the authors present a numerical method for the generalized Langevin equation of motion with skewed random forcing for the case of homogeneous, skewed turbulence. The authors begin by showing how the analytic solution to the Langevin equation for this case can be used to determine the relationship between the particle velocity moments and the properties of the skewed random force. They then present a numerical method that uses simple probability distribution functions to simulate the effect of the random force. The numerical solution is shown to be exact in the limit of infinitesimal time steps, and to be within acceptable error limits when practical time steps are used.

  15. Bayesian QTL mapping using skewed Student-t distributions

    PubMed Central

    von Rohr, Peter; Hoeschele, Ina

    2002-01-01

    In most QTL mapping studies, phenotypes are assumed to follow normal distributions. Deviations from this assumption may lead to detection of false positive QTL. To improve the robustness of Bayesian QTL mapping methods, the normal distribution for residuals is replaced with a skewed Student-t distribution. The latter distribution is able to account for both heavy tails and skewness, and both components are each controlled by a single parameter. The Bayesian QTL mapping method using a skewed Student-t distribution is evaluated with simulated data sets under five different scenarios of residual error distributions and QTL effects. PMID:11929622

  16. Bridge Inspector's Training Manual.

    ERIC Educational Resources Information Center

    Federal Highway Administration (DOT), Washington, DC. Bureau of Public Roads.

    A guide for the instruction of bridge inspectors is provided in this manual as well as instructions for conducting and reporting on a bridge inspection. The chapters outline the qualifications necessary to become a bridge inspector. The subject areas covered are: The Bridge Inspector, Bridge Structures, Bridge Inspection Reporting System,…

  17. The Belizean Bridge Activity.

    ERIC Educational Resources Information Center

    Murfin, Brian

    2000-01-01

    Describes the famous swing bridge in Belize. Students build bridges from a variety of materials and answer the questions, What are different types of bridges?, How do bridges work?, How can you tell if a bridge design will be safe?, and What is the best way to build a bridge over a river while still allowing boat traffic? (SAH)

  18. Flexion and Skewness in Map Projections of the Earth

    E-print Network

    David M. Goldberg; J. Richard Gott III

    2007-04-12

    Tissot indicatrices have provided visual measures of local area and isotropy distortions. Here we show how large scale distortions of flexion (bending) and skewness (lopsidedness) can be measured. Area and isotropy distortions depend on the map projection metric, flexion and skewness, which manifest themselves on continental scales, depend on the first derivatives of the metric. We introduce new indicatrices that show not only area and isotropy distortions but flexion and skewness as well. We present a table showing error measures for area, isotropy, flexion, skewness, distances, and boundary cuts allowing us to compare different world map projections. We find that the Winkel-Tripel projection (already adopted for world maps by the National Geographic), has low distortion on most measures and excellent quality overall.

  19. PRINCIPLE OF SKEW QUADRUPOLE MODULATION TO MEASURE BETATRON COUPLING.

    SciTech Connect

    LUO.Y.PILAT,F.ROSER,T.ET AL.

    2004-07-05

    The measurement of the residual betatron coupling via skew quadrupole modulation is a new diagnostics technique that has been developed and tested at the Relativistic Heavy Ion Collider (RHIC) as a very promising method for the linear decoupling on the ramp. By modulating the strengths of different skew quadrupole families the two eigentunes are precisely measured with the phase lock loop system. The projections of the residual coupling coefficient onto the skew quadrupole coupling modulation directions are determined. The residual linear coupling could be corrected according to the measurement. An analytical solution for skew quadrupole modulation based on Hamiltonian perturbation approximation is given, and simulation code using smooth accelerator model is also developed. Some issues concerning the practical applications of this technique are discussed.

  20. Reproductive skew in female common marmosets: what can proximate mechanisms

    E-print Network

    Saltzman, Wendy

    -imposed by most subordinates, consistent with restraint models of reproductive skew. In contrast to restraint appears to be generated predominantly by subordinate self-restraint, in a proximate sense, but ultimately

  1. Bicriterion seriation methods for skew-symmetric matrices.

    PubMed

    Brusco, Michael J; Stahl, Stephanie

    2005-11-01

    The decomposition of an asymmetric proximity matrix into its symmetric and skew-symmetric components is a well-known principle in combinatorial data analysis. The seriation of the skew-symmetric component can emphasize information corresponding to the sign or absolute magnitude of the matrix elements, and the choice of objective criterion can have a profound impact on the ordering. In this research note, we propose a bicriterion approach for seriation of a skew-symmetric matrix incorporating both sign and magnitude information. Two numerical demonstrations reveal that the bicriterion procedure is an effective alternative to direct seriation of the skew-symmetric matrix, facilitating favourable trade-offs among sign and magnitude information. PMID:16293204

  2. Systems of Differential Equations with Skew-Symmetric, Orthogonal Matrices

    ERIC Educational Resources Information Center

    Glaister, P.

    2008-01-01

    The solution of a system of linear, inhomogeneous differential equations is discussed. The particular class considered is where the coefficient matrix is skew-symmetric and orthogonal, and where the forcing terms are sinusoidal. More general matrices are also considered.

  3. Skewed exponential pairwise velocities from Gaussian initial conditions

    SciTech Connect

    Juszkiewicz, R.; Fisher, K. B.; Szapudi, I.

    1998-09-01

    Using an Eulerian perturbative calculation, we show that the distribution of relative pairwise velocities which arises from gravitational instability of Gaussian density fluctuations has asymmetric (skewed) exponential tails. The negative skewness is induced by the negative mean streaming velocity of pairs (the infall prevails over expansion), while the exponential tails arise because the relative pairwise velocity is a number, not volume weighted statistic. The derived probability distribution is compared with N-body simulations and shown to provide a reasonable fit.

  4. BRIDGE Summary Minutes BRIDGE Group Meeting

    E-print Network

    BRIDGE Summary Minutes 02.16.10 1 BRIDGE Group Meeting Date: 03.16.10 Agenda 1. Workplace violence is trying to distribute training on how to react if there is an active shooter on campus. He asked BRIDGE it is #12;BRIDGE Summary Minutes 02.16.10 2 complimented by an advanced communications system throughout

  5. BRIDGE Summary Minutes BRIDGE Group Meeting

    E-print Network

    BRIDGE Summary Minutes 07.19.11 1 BRIDGE Group Meeting Date: 07.19.11 Agenda 1. FM Sign Shop 2 unless directed to do so. The bulletin #12;BRIDGE Summary Minutes 07.19.11 2 boards in Moos tower · Keller (EECsi) · McNeal · Nicholson · Rapson #12;BRIDGE Summary Minutes 07.19.11 3 · Ruttan (CoB) · STSS

  6. BRIDGE Summary Minutes BRIDGE Group Meeting

    E-print Network

    BRIDGE Summary Minutes 07.17.12 1 BRIDGE Group Meeting Date: 07.17.12 Agenda 1. Elevator Update 2 informed BRIDGE members about potential changes in the way elevators/escalators are maintained-business hours during the week and 90 minutes during non-business hours during the weekend. #12;BRIDGE Summary

  7. BRIDGE Summary Minutes BRIDGE Group Meeting

    E-print Network

    BRIDGE Summary Minutes 05.21.13 1 BRIDGE Group Meeting Date: 05.21.13 Agenda 1. Introductions 2 to schedule time for the outages due to many disparate customer needs. He appealed for the BRIDGE members help up is a completely redundant system which is #12;BRIDGE Summary Minutes 05.21.13 2 used in the most

  8. BRIDGE Summary Minutes BRIDGE Group Meeting

    E-print Network

    BRIDGE Summary Minutes 02.16.10 1 BRIDGE Group Meeting Date: 02.16.10 Agenda 1. U Construction CPPM and FM Districts. Mike then walked BRIDGE members through a swim-lane document which presented how process for targeted projects. #12;BRIDGE Summary Minutes 02.16.10 2 Mike then introduced Dean Spratt

  9. BRIDGE Summary Minutes BRIDGE Group Meeting

    E-print Network

    BRIDGE Summary Minutes 09.20.11 1 BRIDGE Group Meeting Date: 09.20.11 Agenda 1. Six-year Capital the directions, Brian invited BRIDGE members to call him with any questions. Q&A Is there a million dollar of power and University #12;BRIDGE Summary Minutes 09.20.11 2 equipment as well as developing design

  10. BRIDGE Summary Minutes BRIDGE Group Meeting

    E-print Network

    BRIDGE Summary Minutes 05.25.10 1 BRIDGE Group Meeting Date: 05.18.10 Agenda 1. CPPM FY 11 Rates and he is sure that they will be making adjustments. He asked BRIDGE members to remain patient. The rate will reduce 16 positions initially and evaluate an additional 8 positions during FY11. #12;BRIDGE Summary

  11. BRIDGE Summary Minutes BRIDGE Group Meeting

    E-print Network

    BRIDGE Summary Minutes 05.17.11 1 BRIDGE Group Meeting Date: 05.17.11 Agenda 1. LRT Update 2 dynamic situation. She asked that BRIDGE members let the U Services Vice President's Office know on the Cedar Ave. Bridge? We are aware of the initial slow traffic and traffic control agents

  12. BRIDGE Summary Minutes BRIDGE Group Meeting

    E-print Network

    BRIDGE Summary Minutes 03.20.12 1 BRIDGE Group Meeting Date: 03.20.12 Agenda 1. Meet CPPM AVP and private sector engagements (see attached bio). Suzanne said she is looking forward to working with BRIDGE of Transportation. Tim also reminded BRIDGE members that when completed the project will be a benefit

  13. Flow in Rotating Serpentine Coolant Passages With Skewed Trip Strips

    NASA Technical Reports Server (NTRS)

    Tse, David G.N.; Steuber, Gary

    1996-01-01

    Laser velocimetry was utilized to map the velocity field in serpentine turbine blade cooling passages with skewed trip strips. The measurements were obtained at Reynolds and Rotation numbers of 25,000 and 0.24 to assess the influence of trips, passage curvature and Coriolis force on the flow field. The interaction of the secondary flows induced by skewed trips with the passage rotation produces a swirling vortex and a corner recirculation zone. With trips skewed at +45 deg, the secondary flows remain unaltered as the cross-flow proceeds from the passage to the turn. However, the flow characteristics at these locations differ when trips are skewed at -45 deg. Changes in the flow structure are expected to augment heat transfer, in agreement with the heat transfer measurements of Johnson, et al. The present results show that trips are skewed at -45 deg in the outward flow passage and trips are skewed at +45 deg in the inward flow passage maximize heat transfer. Details of the present measurements were related to the heat transfer measurements of Johnson, et al. to relate fluid flow and heat transfer measurements.

  14. Level II scour analysis for Bridge 25 (BRNATH00290034) on Town Highway 29, crossing Locust Creek, Barnard, Vermont

    USGS Publications Warehouse

    Ivanoff, Michael A.; Weber, Matthew A.

    1996-01-01

    The Town Highway 29 crossing of Locust Creek is a 37-ft-long, one-lane bridge consisting of one 32-foot concrete span (Vermont Agency of Transportation, written communication, August 23, 1994). The bridge is supported by vertical, concrete abutments with wingwalls. The channel is skewed approximately 25 degrees to the opening while the opening-skew-to-roadway is 25 degrees. There was no observable scour protection measure at the site. Additional details describing conditions at the site are included in the Level II Summary and Appendices D and E.

  15. SAMP Bridge Mark Taylor

    E-print Network

    Taylor, Mark

    SAMP Bridge Mark Taylor (AstroGrid, Bristol) IVOA Interop Meeting, ESO 9 November 2009 $Id: bridge/9 #12;Operation 1. Two independent hubs are running 2. Bridge starts up, connects to both hubs Mark are running 2. Bridge starts up, connects to both hubs 3. Proxies for Hub 2 clients, controlled by Bridge

  16. Quantum Fisher and Skew information for Unruh accelerated Dirac qubit

    E-print Network

    Subhashish Banerjee; Ashutosh Kumar Alok; S. Omkar

    2015-11-10

    We develop a Bloch vector representation of Unruh channel for a Dirac field mode. This is used to provide a unified, analytical treatment of quantum Fisher and Skew information for a qubit subjected to the Unruh channel, both in its pure form as well as in the presence of experimentally relevant external noise channels. The time evolution of Fisher and Skew information is studied along with the impact of external environment parameters such as temperature and squeezing. The external noises are modelled by both purely dephasing phase damping as well as the squeezed generalized amplitude damping channels. An interesting interplay between the external reservoir temperature and squeezing on the Fisher and Skew information is observed, in particular, for the action of the squeezed generalized amplitude damping channel. It is seen that for some regimes, squeezing can enhance the quantum information against the deteriorating influence of the ambient environment. Similar features are also observed for the analogous study of Skew information, highlighting the similar origin of the Fisher and Skew information.

  17. Quantum Fisher and Skew information for Unruh accelerated Dirac qubit

    E-print Network

    Banerjee, Subhashish; Omkar, S

    2015-01-01

    We develop a Bloch vector representation of Unruh channel for a Dirac field mode. This is used to provide a unified, analytical treatment of quantum Fisher and Skew information for a qubit subjected to the Unruh channel, both in its pure form as well as in the presence of experimentally relevant external noise channels. The time evolution of Fisher and Skew information is studied along with the impact of external environment parameters such as temperature and squeezing. The external noises are modelled by both purely dephasing phase damping as well as the squeezed generalized amplitude damping channels. An interesting interplay between the external reservoir temperature and squeezing on the Fisher and Skew information is observed, in particular, for the action of the squeezed generalized amplitude damping channel. It is seen that for some regimes, squeezing can enhance the quantum information against the deteriorating influence of the ambient environment. Similar features are also observed for the analogous s...

  18. Determining collective barrier operation skew in a parallel computer

    SciTech Connect

    Faraj, Daniel A.

    2015-11-24

    Determining collective barrier operation skew in a parallel computer that includes a number of compute nodes organized into an operational group includes: for each of the nodes until each node has been selected as a delayed node: selecting one of the nodes as a delayed node; entering, by each node other than the delayed node, a collective barrier operation; entering, after a delay by the delayed node, the collective barrier operation; receiving an exit signal from a root of the collective barrier operation; and measuring, for the delayed node, a barrier completion time. The barrier operation skew is calculated by: identifying, from the compute nodes' barrier completion times, a maximum barrier completion time and a minimum barrier completion time and calculating the barrier operation skew as the difference of the maximum and the minimum barrier completion time.

  19. Determining collective barrier operation skew in a parallel computer

    DOEpatents

    Faraj, Daniel A.

    2015-12-24

    Determining collective barrier operation skew in a parallel computer that includes a number of compute nodes organized into an operational group includes: for each of the nodes until each node has been selected as a delayed node: selecting one of the nodes as a delayed node; entering, by each node other than the delayed node, a collective barrier operation; entering, after a delay by the delayed node, the collective barrier operation; receiving an exit signal from a root of the collective barrier operation; and measuring, for the delayed node, a barrier completion time. The barrier operation skew is calculated by: identifying, from the compute nodes' barrier completion times, a maximum barrier completion time and a minimum barrier completion time and calculating the barrier operation skew as the difference of the maximum and the minimum barrier completion time.

  20. THE TRUSS BRIDGE SEGMENT OF THE TRIBOROUGH BRIDGE IN FOREGROUND ...

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

    THE TRUSS BRIDGE SEGMENT OF THE TRIBOROUGH BRIDGE IN FOREGROUND AND THE HELL GATE BRIDGE IN THE BACKGROUND ADJACENT TO THE SUSPENSION SEGMENT OF THE TRIBOROUGH BRIDGE. - Triborough Bridge, Passing through Queens, Manhattan & the Bronx, Queens (subdivision), Queens County, NY

  1. BRIDGE Summary Minutes BRIDGE Group Meeting

    E-print Network

    BRIDGE Summary Minutes 11.15.11 1 BRIDGE Group Meeting Date: 11.15.11 Agenda 1. Snow Removal Plans be reached at 4-6400 or pmwright@umn.edu. BRIDGE members were invited to join a tour of SuperValu's flex;BRIDGE Summary Minutes 11.15.11 2 Are there any plans to educate students about the Gopher way? That

  2. Latitudinal skewness in global EQ distributions

    NASA Astrophysics Data System (ADS)

    Sasorova, E.; Levin, B.

    2009-04-01

    The results of statistical analysis of worldwide seismic catalogs (ISC and NEIC), which was carried out in frame of two projects are presented. In both cases we extracted the evens occurred in the Pacific region from 1964 with Mb>=4.0. The aftershocks were canceled from the list. All events were divided into following magnitude ranges (MR): 4<=Mb<4.5; 4.5<=Mb<5; 5<=Mb<5.5; 5.5<=Mb<6.0; 6<=Mb. Further analysis was performed separately for each MR. In frame of the first project [Levin, Sasorova, 2009] the whole Pacific region was divided in 18 latitudinal intervals (size of every interval was 10 deg). The number of events in each latitudinal interval was normalized two times. The first one number of events was divided on common number of events in given MR. It was calculated relative number of events in each latitudinal interval for given MR. Then normalization was produced with respect to the length of lithosphere plate boundaries situated in given latitude zone. The approach gives the characteristic of seismicity for lithosphere plate boundary, i.e. seismic event number which was generated at unit of length of plate boundary. An analysis of the Pacific earthquake latitude distribution showed that the empirical distribution is described by a bimodal function with two maxima in middle latitudes (40-50 deg N and 20-30 deg S), local minimum near equator (10-20 deg N), and zero values in polar zones. Thus the bimodal latitudinal EQ distribution shows clear expressed skewness (in direction to the Northern Hemisphere). The stability of distributions from the observation interval size was demonstrated on the data independence analysis for several ten-year intervals. Then it was carried out the analysis about statistically valid regularity of the EQ distribution over depth and over latitudinal belts for different magnitude ranges (MR). It was shown, that for the high latitudes up to 90% of the EQ sources are located on the depth H<=20 km. The part of EQ with 20=500 km (deep EQ). In this case clear expressed peak of deep EQ belongs on latitudinal belt 30-20 deg S In frame of the second project [Levin, Sasorova, 2005; Sasorova, Levin, Emelyanova, 2006] statistical verification of hypothesis about existence non-random component in time distribution of the EQs between the Northern and Southern part of the Pacific was carried out. The distribution-free test (run test with significant level 1%) was used for existence proof of nonrandom component into time sequences. The time sequences of the EQ switching between the Northern and Southern parts of the Pacific region contain statistically significant nonrandom component for the events with 4.0<=Mb<6.0. Then data in each magnitude range was subdivided in two groups: the deep earthquakes (H>70km) and the shallow earthquakes (H<=70km). It was found that nonrandom component does not exist for deep earthquakes. On the contrary it is clearly manifested in time distribution of the shallow events. The digital model (superposition of random and periodic processes) was proposed. It was shown that the manifestation of non-random component depends on magnitude of studied events and on the duration of the observation period. The stability of distributions from the observation interval size was demonstrated on the data independence analysis for several eight -year intervals.

  3. BRIDGE Summary Minutes BRIDGE Group Meeting

    E-print Network

    BRIDGE Summary Minutes 07.20.10 1 BRIDGE Group Meeting Date: 07.20.10 Agenda 1. University Space Initiative 2. Standard Bldg Hours & Furlough Plans 3. U Construction Update 4. Sightlines Customer Comments 1 lockers. The professors have appreciated the #12;BRIDGE Summary Minutes 07.20.10 2 change because

  4. Arc voltage distribution skewness as an indicator of electrode gap during vacuum arc remelting

    DOEpatents

    Williamson, Rodney L. (Albuquerque, NM); Zanner, Frank J. (Sandia Park, NM); Grose, Stephen M. (Glenwood, WV)

    1998-01-01

    The electrode gap of a VAR is monitored by determining the skewness of a distribution of gap voltage measurements. A decrease in skewness indicates an increase in gap and may be used to control the gap.

  5. Arc voltage distribution skewness as an indicator of electrode gap during vacuum arc remelting

    DOEpatents

    Williamson, R.L.; Zanner, F.J.; Grose, S.M.

    1998-01-13

    The electrode gap of a VAR is monitored by determining the skewness of a distribution of gap voltage measurements. A decrease in skewness indicates an increase in gap and may be used to control the gap. 4 figs.

  6. Thermocline Feedback Influence on Indian Ocean Dipole Skewness

    NASA Astrophysics Data System (ADS)

    Ng, B.; Cai, W.; Walsh, K. J.

    2014-12-01

    A positive Indian Ocean Dipole (IOD) tends to have stronger cold sea surface temperature anomalies (SSTAs) over the eastern Indian Ocean with greater impacts than warm SSTAs that occur during its negative phase. These impacts from positive IODs range from drought over Australia and Indonesia, to flooding over East Africa and India. Two feedbacks have been suggested as the cause of positive IOD skewness, a positive Bjerknes feedback and a negative SST-cloud-radiation (SCR) feedback, but their relative importance is debated. Using models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) and inter-model statistics, we show that the most important process for IOD skewness is an asymmetry in the thermocline feedback, whereby SSTAs respond to thermocline depth anomalies more strongly during the positive phase than negative phase. This asymmetric thermocline feedback drives IOD skewness despite positive IODs receiving greater damping from the SCR feedback. In response to global warming, although the thermocline feedback strengthens, its asymmetry between positive and negative IODs weakens. This behaviour change explains the reduction in IOD skewness that many models display under global warming.

  7. PERSPECTIVES Biodiversity loss, trophic skew and ecosystem functioning

    E-print Network

    Duffy, J. Emmett

    . Importantly, species loss appears biased toward strong interactors among animals but weak interactors among, Gloucester Point, VA 23062-1346, USA Correspondence: E-mail: jeduffy@vims.edu Abstract Experiments testing such determinism involves biased extinction of large consumers, skewing trophic structure and substantially

  8. M. Alexandra Skewes Carmen Holmgren Charles R. Stern

    E-print Network

    Mojzsis, Stephen J.

    ARTICLE M. Alexandra Skewes Æ Carmen Holmgren Charles R. Stern The Donoso copper-rich, tourmaline Springer-Verlag 2002 Abstract The copper-rich, tourmaline-bearing Donoso breccia pipe is one among more% of the total rock volume consisting of breccia-matrix min- erals, which include tourmaline, quartz

  9. Clock Skew Scheduling for Timing Speculation , Feng Yuan

    E-print Network

    Zhou, Hai

    and industry. In this work, we formulate the clock skew scheduling problem for circuits equipped with timing REliable Computing Laboratory (CURE) Department of Computer Science & Engineering The Chinese University of Hong Kong, Shatin, N.T., Hong Kong Shenzhen Institutes of Advanced Technology, Chinese Academy

  10. Making Skew-Resistant Fabrics For Composite Layups

    NASA Technical Reports Server (NTRS)

    Farley, Gary L.

    1994-01-01

    Fabrics used in curved composite-material structures prevented from skewing during composite layup by weaving them in modified process in which warp and fill yarns bonded together at their points of contact. (Bonding concept may prove similarly beneficial for braided and knitted fabrics.) In modified weaving process, adhesives prevent excessive shifting of warp and fill yarns with respect to each other.

  11. Root waving and skewing: unexpectedly in micro-g.

    PubMed

    Roux, Stanley J

    2012-01-01

    Gravity has major effects on both the form and overall length of root growth. Numerous papers have documented these effects (over 300 publications in the last 5 years), the most well-studied being gravitropism, which is a growth re-orientation directed by gravity toward the earth's center. Less studied effects of gravity are undulations due to the regular periodic change in the direction root tips grow, called waving, and the slanted angle of growth roots exhibit when they are growing along a nearly-vertical surface, called skewing. Although diverse studies have led to the conclusion that a gravity stimulus is needed for plant roots to show waving and skewing, the novel results just published by Paul et al. (2012) reveal that this conclusion is not correct. In studies carried out in microgravity on the International Space Station, the authors used a new imaging system to collect digital photographs of plants every six hours during 15 days of spaceflight. The imaging system allowed them to observe how roots grew when their orientation was directed not by gravity but by overhead LED lights, which roots grew away from because they are negatively phototropic. Surprisingly, the authors observed both skewing and waving in spaceflight plants, thus demonstrating that both growth phenomena were gravity independent. Touch responses and differential auxin transport would be common features of root waving and skewing at 1-g and micro-g, and the novel results of Paul et al. will focus the attention of cell and molecular biologists more on these features as they try to decipher the signaling pathways that regulate root skewing and waving. PMID:23217095

  12. Correcting Quadrupole Roll in Magnetic Lenses with Skew Quadrupoles

    SciTech Connect

    Walstrom, Peter Lowell

    2014-11-10

    Quadrupole rolls (i.e. rotation around the magnet axis) are known to be a significant source of image blurring in magnetic quadrupole lenses. These rolls may be caused by errors in mechanical mounting of quadrupoles, by uneven radiation-induced demagnetization of permanent-magnet quadrupoles, etc. Here a four-quadrupole ×10 lens with so-called ”Russian” or A -B B-A symmetry is used as a model problem. Existing SLAC 1/2 in. bore high-gradient quadrupoles are used in the design. The dominant quadrupole roll effect is changes in the first-order part of the transfer map (the R matrix) from the object to the image plane (Note effects on the R matrix can be of first order in rotation angle for some R-matrix elements and second order in rotation angle for other elements, as shown below). It is possible to correct roll-induced image blur by mechanically adjusting the roll angle of one or more of the quadrupoles. Usually, rotation of one quadrupole is sufficient to correct most of the combined effect of rolls in all four quadrupoles. There are drawbacks to this approach, however, since mechanical roll correction requires multiple entries into experimental area to make the adjustments, which are made according to their effect on images. An alternative is to use a single electromagnetic skew quadrupole corrector placed either between two of the quadrupoles or after the fourth quadrupole (so-called “non-local” correction). The basic feasibility of skew quadrupole correction of quadrupole roll effects is demonstrated here. Rolls of the third lens quadrupole of up to about 1 milliradian can be corrected with a 15 cm long skew quadrupole with a gradient of up to 1 T/m. Since the effect of rolls of the remaining three lens quadrupoles are lower, a weaker skew quadrupole can be used to correct them. Non-local correction of quadrupole roll effects by skew quadrupoles is shown to be about one-half as effective as local correction (i.e. rotating individual quadrupoles to zero roll angle or placing skew quadrupole correctors in the bores of main quadrupoles).

  13. Universal relation between skewness and kurtosis in complex dynamics.

    PubMed

    Cristelli, Matthieu; Zaccaria, Andrea; Pietronero, Luciano

    2012-06-01

    We identify an important correlation between skewness and kurtosis for a broad class of complex dynamic systems and present a specific analysis of earthquake and financial time series. Two regimes of non-Gaussianity can be identified: a parabolic one, which is common in various fields of physics, and a power law one, with exponent 4/3, which at the moment appears to be specific of earthquakes and financial markets. For this property we propose a model and an interpretation in terms of very rare events dominating the statistics independently on the nature of the events considered. The predicted scaling relation between skewness and kurtosis matches very well the experimental pattern of the second regime. Regarding price fluctuations, this situation characterizes a universal stylized fact. PMID:23005163

  14. Skewed Brownian Fluctuations in Single-Molecule Magnetic Tweezers

    PubMed Central

    Burnham, Daniel R.; De Vlaminck, Iwijn; Henighan, Thomas; Dekker, Cees

    2014-01-01

    Measurements in magnetic tweezers rely upon precise determination of the position of a magnetic microsphere. Fluctuations in the position due to Brownian motion allows calculation of the applied force, enabling deduction of the force-extension response function for a single DNA molecule that is attached to the microsphere. The standard approach relies upon using the mean of position fluctuations, which is valid when the microsphere axial position fluctuations obey a normal distribution. However, here we demonstrate that nearby surfaces and the non-linear elasticity of DNA can skew the distribution. Through experiment and simulations, we show that such a skewing leads to inaccurate position measurements which significantly affect the extracted DNA extension and mechanical properties, leading to up to two-fold errors in measured DNA persistence length. We develop a simple, robust and easily implemented method to correct for such mismeasurements. PMID:25265383

  15. Newspaper Coverage of Intimate Partner Violence: Skewing Representations of Risk

    PubMed Central

    Carlyle, Kellie E.; Slater, Michael D.; Chakroff, Jennifer L.

    2011-01-01

    How media portray intimate partner violence (IPV) has implications for public perceptions and social policy. Therefore, to better understand these portrayals, this study content analyzes a nationally representative sample of newspaper coverage of IPV over a two-year-period and compares this coverage to epidemiological data in order to examine the implications of the discrepancies between coverage and social reality. Stratified media outlets across the country were used to obtain a representative sample of daily newspapers based on their designated market areas, resulting in 395 IPV-related articles. Results show that newspaper framing of IPV tends to be heavily skewed toward episodic framing. In addition, there are significant differences between our data and epidemiological estimates, particularly in the coverage of homicide and use of alcohol and illegal drugs, which may skew public perceptions of risk. Implications for public perceptions and social policy are discussed. PMID:21297889

  16. Micromagnetic recording model of writer geometry effects at skew

    NASA Astrophysics Data System (ADS)

    Plumer, M. L.; Bozeman, S.; van Ek, J.; Michel, R. P.

    2006-04-01

    The effects of the pole-tip geometry at the air-bearing surface on perpendicular recording at a skew angle are examined through modeling and spin-stand test data. Head fields generated by the finite element method were used to record transitions within our previously described micromagnetic recording model. Write-field contours for a variety of square, rectangular, and trapezoidal pole shapes were evaluated to determine the impact of geometry on field contours. Comparing results for recorded track width, transition width, and media signal to noise ratio at 0° and 15° skew demonstrate the benefits of trapezoidal and reduced aspect-ratio pole shapes. Consistency between these modeled results and test data is demonstrated.

  17. Identification of spots in rotated and skewed microarray images

    NASA Astrophysics Data System (ADS)

    Le Brese, Christopher; Zou, Ju Jia

    2009-12-01

    DNA microarray image processing has vast potential in the measurement of mass gene expression. A common approach to processing microarrays consists of spot identification, spot segmentation, and information extraction. We are concerned with spot identification. We aim to tackle the problem of identifying spots in rotated and skewed arrays via an automated process. The method proposed is composed of three steps, namely, array orientation calculation based on the Hough transform, affine calculation and correction, and gridding. The method is able to correctly identify spots in a microarray that has been rotated or skewed at an angle between 0 and +/-30 deg and corrupted by various types of noise such as high-intensity streaks, Gaussian noise, and salt-and-pepper noise.

  18. Multivariate Skew-t Distributions in Econometrics and Environmetrics 

    E-print Network

    Marchenko, Yulia V.

    2012-02-14

    of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved by: Chair of Committee, Marc G. Genton Committee Members, Raymond J. Carroll Mohsen Pourahmadi Kenneth P. Bowman Head of Department, Simon J. Sheather December 2010 Major Subject: Statistics... iii ABSTRACT Multivariate Skew-t Distributions in Econometrics and Environmetrics. (December 2010) Yulia V. Marchenko, Diploma, Belarussian State University, Minsk, Belarus; M.S., Texas A&M University Chair of Advisory Committee: Dr. Marc G...

  19. Skew and twist resistant hydrodynamic rotary shaft seal

    DOEpatents

    Dietle, L.; Kalsi, M.S.

    1999-02-23

    A hydrodynamically lubricated squeeze packing type rotary shaft seal suitable for lubricant retention and environmental exclusion which incorporates one or more resilient protuberances which cooperate with the gland walls to hold the seal straight in its installation groove in unpressurized and low pressure lubricant retention applications thereby preventing skew-induced wear caused by impingement of abrasive contaminants present in the environment, and which also serve as radial bearings to prevent tipping of the seal within its installation gland. 14 figs.

  20. Skew and twist resistant hydrodynamic rotary shaft seal

    DOEpatents

    Dietle, Lannie (Sugar Land, TX); Kalsi, Manmohan Singh (Houston, TX)

    1999-01-01

    A hydrodynamically lubricated squeeze packing type rotary shaft seal suitable for lubricant retention and environmental exclusion which incorporates one or more resilient protuberances which and cooperate with the gland walls to hold the seal straight in its installation groove in unpressurized and low pressure lubricant retention applications thereby preventing skew-induced wear caused by impingement of abrasive contaminants present in the environment, and which also serve as radial bearings to prevent tipping of the seal within its installation gland.

  1. Bridging spinal cord injuries

    E-print Network

    2008-10-15

    Abstract One strategy for spinal cord injury repair is to make cellular bridges that support axon regeneration. However, the bridging cells often fail to integrate with host tissue and may lead to increased pain sensitivity. Recent work has tested...

  2. Digital Planetaria: Building Bridges

    E-print Network

    Collar, Juan I.

    Digital Planetaria: Building Bridges Building Bridges Between Institutions, Universities for collaboration between NASA, digital planetarium experts, formal and informal science education facilities and educational digital planetarium presentations. Over the course of the two-day Focus Group and subsequent

  3. A longitudinal analysis of reproductive skew in male rhesus macaques.

    PubMed Central

    Widdig, Anja; Bercovitch, Fred B.; Streich, Wolf Jürgen; Sauermann, Ulrike; Nürnberg, Peter; Krawczak, Michael

    2004-01-01

    One of the basic tenets of sexual selection is that male reproductive success should be large in polygynous species. Here, we analysed 6 years of molecular genetic data from a semi-free-ranging population of rhesus macaques (Macaca mulatta), using Nonac's B index, to assess the level of male reproductive skew in the study troop. On average, the top sire in each year produced 24% of the infants, while 71% of troop males sired no offspring at all. Consequently, 74% of infants had at least one paternal half-sibling in their own birth cohort. Reproductive success was greatest for high-ranking males, males who spent the whole mating season in the troop and males of 9-11 years of age. Heterozygosity for major histocompatibility complex (MHC) class II gene DQB1 was the strongest single predictor of male reproductive success. A negative relationship suggestive of female mate choice was noted between the B index and the proportion of extragroup paternities. Reproductive skew was not associated with relatedness among potential sires or with female cycle synchrony. We conclude that reproductive skew in male rhesus macaques is best accounted for by the 'limited-control' model, with multiple factors interacting to regulate individual reproductive output. PMID:15255100

  4. Skew-orthogonal polynomials and random-matrix ensembles.

    PubMed

    Ghosh, Saugata; Pandey, Akhilesh

    2002-04-01

    There is considerable interest in understanding the relation between random-matrix ensembles and quantum chaotic systems in the context of the universality of energy-level correlations. In this connection, while Gaussian ensembles of random matrices have been studied extensively, not much is known about ensembles with non-Gaussian weight functions. Dyson has shown that the n-level correlation functions can be expressed in terms of a kernel function involving orthogonal and skew-orthogonal polynomials--orthogonal for matrix ensembles with unitary invariance and skew orthogonal for ensembles with orthogonal and symplectic invariances. We have obtained the following results. (1) Skew-orthogonal polynomials of both types are derived for the Jacobi class of weight functions including the limiting cases of associated Laguerre and Hermite (or Gaussian). (2) Matrix-integral representations are given for the general weight functions. (3) Asymptotic forms of the polynomials are obtained rigorously for the Jacobi class and in the form of an ansatz for the general case. (4) For the three types of ensembles, the (asymptotic) n-level correlation functions with appropriate scaling are shown to be universal, being independent of the weight function and location in the spectrum, and identical with the well-known Gaussian results. This provides a rigorous justification for the universality of the Gaussian ensemble results observed in quantum chaotic systems. As expected, the level density is not universal. PMID:12005990

  5. Kurtosis, skewness, and non-Gaussian cosmological density perturbations

    NASA Technical Reports Server (NTRS)

    Luo, Xiaochun; Schramm, David N.

    1993-01-01

    Cosmological topological defects as well as some nonstandard inflation models can give rise to non-Gaussian density perturbations. Skewness and kurtosis are the third and fourth moments that measure the deviation of a distribution from a Gaussian. Measurement of these moments for the cosmological density field and for the microwave background temperature anisotropy can provide a test of the Gaussian nature of the primordial fluctuation spectrum. In the case of the density field, the importance of measuring the kurtosis is stressed since it will be preserved through the weakly nonlinear gravitational evolution epoch. Current constraints on skewness and kurtosis of primeval perturbations are obtained from the observed density contrast on small scales and from recent COBE observations of temperature anisotropies on large scales. It is also shown how, in principle, future microwave anisotropy experiments might be able to reveal the initial skewness and kurtosis. It is shown that present data argue that if the initial spectrum is adiabatic, then it is probably Gaussian, but non-Gaussian isocurvature fluctuations are still allowed, and these are what topological defects provide.

  6. Validation of an Acoustic Impedance Prediction Model for Skewed Resonators

    NASA Technical Reports Server (NTRS)

    Howerton, Brian M.; Parrott, Tony L.

    2009-01-01

    An impedance prediction model was validated experimentally to determine the composite impedance of a series of high-aspect ratio slot resonators incorporating channel skew and sharp bends. Such structures are useful for packaging acoustic liners into constrained spaces for turbofan noise control applications. A formulation of the Zwikker-Kosten Transmission Line (ZKTL) model, incorporating the Richards correction for rectangular channels, is used to calculate the composite normalized impedance of a series of six multi-slot resonator arrays with constant channel length. Experimentally, acoustic data was acquired in the NASA Langley Normal Incidence Tube over the frequency range of 500 to 3500 Hz at 120 and 140 dB OASPL. Normalized impedance was reduced using the Two-Microphone Method for the various combinations of channel skew and sharp 90o and 180o bends. Results show that the presence of skew and/or sharp bends does not significantly alter the impedance of a slot resonator as compared to a straight resonator of the same total channel length. ZKTL predicts the impedance of such resonators very well over the frequency range of interest. The model can be used to design arrays of slot resonators that can be packaged into complex geometries heretofore unsuitable for effective acoustic treatment.

  7. Low nasal bridge

    MedlinePLUS

    A low nasal bridge is a flattening of the top part of the nose. ... Decreased growth (hypoplasia) of the nasal bridge may due to infections or genetic diseases. A decrease in the height of the nasal bridge is best seen from a side ...

  8. Severe Skew Foot Deformity in a Patient With Freeman-Sheldon Syndrome

    PubMed Central

    Kaissi, Ali Al; Klaushofer, Klaus; Grill, Franz

    2011-01-01

    We report on a 3-year-old boy with the full phenotypic features of Freeman Sheldon syndrome (FSS). Severe skew foot deformity has been recognized as additional skeletal abnormality. Parents were first degree cousins, raising the possibility of autosomal recessive pattern of inheritance. To the best of our knowledge this is the first report of severe skew foot deformity in a patient with (FSS). Keywords Freeman-Sheldon syndrome; Skew foot deformity; Metatarsus adductus PMID:22383916

  9. Correlating the skewness and kurtosis of baryon number distributions

    E-print Network

    Wei-jie Fu; Jan M. Pawlowski

    2015-12-28

    The skewness and the kurtosis of the baryon number distributions are computed within QCD-improved low energy effective models including quantum thermal and density fluctuations. The results are compared with the Beam Energy Scan experiment at RHIC. The theoretical results agree with the experimental measurements up to errors, for the colliding energy $\\sqrt{s}\\ge 19.6\\,\\mathrm{GeV}$. For smaller colliding energies a discrepancy between theoretical and experimental results develops. This is explained with the lack of precision of the current set-up for small colliding energies. It is outlined how this deficiency can be overcome.

  10. Skew And Twist Resistant Hydrodynamic Rotary Shaft Seal

    DOEpatents

    Dietle, Lannie (Sugar Land, TX); Kalsi, Manmohan Singh (Houston, TX)

    2000-03-14

    A hydrodynamically lubricated squeeze packing type rotary shaft seal suitable for lubricant retention and environmental exclusion which incorporates one or more resilient protuberances which and cooperate with the gland walls to hold the seal straight in its installation groove in unpressurized and low pressure lubricant retention applications thereby preventing skew-induced wear caused by impingement of abrasive contaminants present in the environment, and which also serve as radial bearings to prevent tipping of the seal within its installation gland. Compared to prior art, this invention provides a dramatic reduction of seal and shaft wear in abrasive environments and provides a significant increase in seal life.

  11. Effect of Resonator Axis Skew on Normal Incidence Impedance

    NASA Technical Reports Server (NTRS)

    Parrott, Tony L.; Jones, Michael G.; Homeijer, Brian

    2003-01-01

    High by-pass turbofan engines have fewer fan blades and lower rotation speeds than their predecessors. Consequently, the noise suppression at the low frequency end of the noise spectra has become an increasing concern. This has led to a renewed emphasis on improving noise suppression efficiency of passive, duct liner treatments at the lower frequencies. For a variety of reasons, passive liners are comprised of locally-reacting, resonant absorbers. One reason for this design choice is to satisfy operational and economic requirements. The simplest liner design consists of a single layer of honeycomb core sandwiched between a porous facesheet and an impervious backing plate. These resonant absorbing structures are integrated into the nacelle wall and are very ef- ficient over a limited bandwidth centered on their resonance frequency. Increased noise suppression bandwidth and greater suppression at lower frequencies is typically achieved for conventional liners by increasing the liner depth and incorporating thin porous septa into the honeycomb core. However, constraints on liner depth in modern high by-pass engine nacelles severely limit the suppression bandwidth extension to lower frequencies. Also, current honeycomb core liners may not be suitable for irregular geometric volumes heretofore not considered. It is of interest, therefore, to find ways to circumvent liner depth restrictions and resonator cavity shape constraints. One way to increase effective liner depth is to skew the honeycomb core axis relative to the porous facesheet surface. Other possibilities are to alter resonator cavity shape, e.g. high aspect ratio, narrow channels that possibly include right angle bends, 180. channel fold-backs, and splayed channel walls to conform to irregular geometric constraints. These possibilities constitute the practical motivation for expanding impedance modeling capability to include unconventional resonator orientations and shapes. The work reported in this paper is in the nature of a progress report and is limited to examining the implications of resonator axis skew on the composite normal incidence impedance of an array of resonator channels. Specifically, experimental results are compared with a modified impedance prediction model for highaspect- ratio, rectangular, resonator channels with varying amounts of skew relative to the incident particle velocity. It is shown that for resonator channel widths of 1 to 2 mm, aspect ratios of 25 to 50, and skew angles of zero to sixty degrees, the surface impedance of test models can be predicted with good accuracy. Predicted resistances and reactances are particularly well correlated through the first resonance and first anti-resonance for all six test models investigated. Beyond the first anti-resonance, the impedance prediction model loses the ability to predict details of resistance and reactance but still predicts the mean trends very well.

  12. LOOKING WNW, CHEVROLET AVENUE BRIDGE CROSSING FLINT RIVER. BRIDGE CONNECTED ...

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

    LOOKING WNW, CHEVROLET AVENUE BRIDGE CROSSING FLINT RIVER. BRIDGE CONNECTED NORTH AND SOUTH PORTIONS OF FACTORY COMPLEX. DANIEL LUTEN DESIGNED THE BRIDGE, AND ILLINOIS BRIDGE COMPANY BUILT IT IN 1918. THE BRIDGE WAS THE SITE OF THE BATTLE OF RUNNING BULLS IN THE 1936-1937 GM SIT DOWN STRIKE. - Delphi Flint West, 300 Chevrolet Avenue, Flint, Genesee County, MI

  13. A novel bridge scour monitoring and prediction system

    NASA Astrophysics Data System (ADS)

    Valyrakis, Manousos; Michalis, Panagiotis; Zhang, Hanqing

    2015-04-01

    Earth's surface is continuously shaped due to the action of geophysical flows. Erosion due to the flow of water in river systems has been identified as a key problem in preserving ecological health but also a threat to our built environment and critical infrastructure, worldwide. As an example, it has been estimated that a major reason for bridge failure is due to scour. Even though the flow past bridge piers has been investigated both experimentally and numerically, and the mechanisms of scouring are relatively understood, there still lacks a tool that can offer fast and reliable predictions. Most of the existing formulas for prediction of bridge pier scour depth are empirical in nature, based on a limited range of data or for piers of specific shape. In this work, the use of a novel methodology is proposed for the prediction of bridge scour. Specifically, the use of an Adaptive Neuro-Fuzzy Inference System (ANFIS) is proposed to estimate the scour depth around bridge piers. In particular, various complexity architectures are sequentially built, in order to identify the optimal for scour depth predictions, using appropriate training and validation subsets obtained from the USGS database (and pre-processed to remove incomplete records). The model has five variables, namely the effective pier width (b), the approach velocity (v), the approach depth (y), the mean grain diameter (D50) and the skew to flow. Simulations are conducted with data groups (bed material type, pier type and shape) and different number of input variables, to produce reduced complexity and easily interpretable models. Analysis and comparison of the results indicate that the developed ANFIS model has high accuracy and outstanding generalization ability for prediction of scour parameters. The effective pier width (as opposed to skew to flow) is amongst the most relevant input parameters for the estimation. Training of the system to new bridge geometries and flow conditions can be achieved by obtaining real time data, via novel electromagnetic sensors monitoring scour depth. Once the model is trained with data representative of the new system, bridge scour prediction can be performed for high/design flows or floods.

  14. Galactic Bridges in Pairs

    NASA Astrophysics Data System (ADS)

    Thierjung, Brianna; Jorge Moreno, Paul Torrey, Phil Hopkins

    2016-01-01

    We employ a suite of 75 simulations of galaxies in idealized major mergers to investigate the bridges formed by interactions. These simulations are based on the Feedback in Realistic Environments (FIRE) model (Hopkins et al. 2011). Moreover, unlike past work, we have both the resolution and diversity in merging orbits to make statistically meaningful predictions. We find that very dense, star forming bridges can be characterized as strong bridges. In particular, prograde mergers with high eccentricities and high impact parameters produce the most mass of stars in the bridge.

  15. Semiconductor bridge (SCB) detonator

    DOEpatents

    Bickes, Jr., Robert W. (Albuquerque, NM); Grubelich, Mark C. (Albuquerque, NM)

    1999-01-01

    The present invention is a low-energy detonator for high-density secondary-explosive materials initiated by a semiconductor bridge igniter that comprises a pair of electrically conductive lands connected by a semiconductor bridge. The semiconductor bridge is in operational or direct contact with the explosive material, whereby current flowing through the semiconductor bridge causes initiation of the explosive material. Header wires connected to the electrically-conductive lands and electrical feed-throughs of the header posts of explosive devices, are substantially coaxial to the direction of current flow through the SCB, i.e., substantially coaxial to the SCB length.

  16. Semiconductor bridge (SCB) detonator

    DOEpatents

    Bickes, R.W. Jr.; Grubelich, M.C.

    1999-01-19

    The present invention is a low-energy detonator for high-density secondary-explosive materials initiated by a semiconductor bridge (SCB) igniter that comprises a pair of electrically conductive lands connected by a semiconductor bridge. The semiconductor bridge is in operational or direct contact with the explosive material, whereby current flowing through the semiconductor bridge causes initiation of the explosive material. Header wires connected to the electrically-conductive lands and electrical feed-throughs of the header posts of explosive devices, are substantially coaxial to the direction of current flow through the SCB, i.e., substantially coaxial to the SCB length. 3 figs.

  17. Crossover ensembles of random matrices and skew-orthogonal polynomials

    SciTech Connect

    Kumar, Santosh; Pandey, Akhilesh

    2011-08-15

    Highlights: > We study crossover ensembles of Jacobi family of random matrices. > We consider correlations for orthogonal-unitary and symplectic-unitary crossovers. > We use the method of skew-orthogonal polynomials and quaternion determinants. > We prove universality of spectral correlations in crossover ensembles. > We discuss applications to quantum conductance and communication theory problems. - Abstract: In a recent paper (S. Kumar, A. Pandey, Phys. Rev. E, 79, 2009, p. 026211) we considered Jacobi family (including Laguerre and Gaussian cases) of random matrix ensembles and reported exact solutions of crossover problems involving time-reversal symmetry breaking. In the present paper we give details of the work. We start with Dyson's Brownian motion description of random matrix ensembles and obtain universal hierarchic relations among the unfolded correlation functions. For arbitrary dimensions we derive the joint probability density (jpd) of eigenvalues for all transitions leading to unitary ensembles as equilibrium ensembles. We focus on the orthogonal-unitary and symplectic-unitary crossovers and give generic expressions for jpd of eigenvalues, two-point kernels and n-level correlation functions. This involves generalization of the theory of skew-orthogonal polynomials to crossover ensembles. We also consider crossovers in the circular ensembles to show the generality of our method. In the large dimensionality limit, correlations in spectra with arbitrary initial density are shown to be universal when expressed in terms of a rescaled symmetry breaking parameter. Applications of our crossover results to communication theory and quantum conductance problems are also briefly discussed.

  18. Skewed sex ratios in India: "physician, heal thyself".

    PubMed

    Patel, Archana B; Badhoniya, Neetu; Mamtani, Manju; Kulkarni, Hemant

    2013-06-01

    Sex selection, a gender discrimination of the worst kind, is highly prevalent across all strata of Indian society. Physicians have a crucial role in this practice and implementation of the Indian Government's Pre-Natal Diagnostic Techniques Act in 1996 to prevent the misuse of ultrasound techniques for the purpose of prenatal sex determination. Little is known about family preferences, let alone preferences among families of physicians. We investigated the sex ratios in 946 nuclear families with 1,624 children, for which either one or both parents were physicians. The overall child sex ratio was more skewed than the national average of 914. The conditional sex ratios decreased with increasing number of previous female births, and a previous birth of a daughter in the family was associated with a 38 % reduced likelihood of a subsequent female birth. The heavily skewed sex ratios in the families of physicians are indicative of a deeply rooted social malady that could pose a critical challenge in correcting the sex ratios in India. PMID:23322380

  19. Characterising Uncertainty in Expert Assessments: Encoding Heavily Skewed Judgements

    PubMed Central

    O’Leary, Rebecca A.; Low-Choy, Samantha; Fisher, Rebecca; Mengersen, Kerrie; Caley, M. Julian

    2015-01-01

    When limited or no observed data are available, it is often useful to obtain expert knowledge about parameters of interest, including point estimates and the uncertainty around these values. However, it is vital to elicit this information appropriately in order to obtain valid estimates. This is particularly important when the experts’ uncertainty about these estimates is strongly skewed, for instance when their best estimate is the same as the lowest value they consider possible. Also this is important when interest is in the aggregation of elicited values. In this paper, we compare alternative distributions for describing such estimates. The distributions considered include the lognormal, mirror lognormal, Normal and scaled Beta. The case study presented here involves estimation of the number of species in coral reefs, which requires eliciting counts within broader taxonomic groups, with highly skewed uncertainty estimates. This paper shows substantial gain in using the scaled Beta distribution, compared with Normal or lognormal distributions. We demonstrate that, for this case study on counting species, applying the novel encoding methodology developed in this paper can facilitate the acquisition of more rigorous estimates of (hierarchical) count data and credible bounds. The approach can also be applied to the more general case of enumerating a sampling frame via elicitation. PMID:26517835

  20. APPROACH BRIDGE PORTION OF VALVE TOWER FOOT BRIDGE, AS SEEN ...

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

    APPROACH BRIDGE PORTION OF VALVE TOWER FOOT BRIDGE, AS SEEN FROM ENTRY. VIEW FACING NORTHWEST - Schofield Barracks Military Reservation, Ku Tree Reservoir, Valve Tower Foot Bridge, Kalakoa Stream, East Range, Wahiawa, Honolulu County, HI

  1. APPROACH BRIDGE PORTION OF VALVE TOWER FOOT BRIDGE, AS SEEN ...

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

    APPROACH BRIDGE PORTION OF VALVE TOWER FOOT BRIDGE, AS SEEN FROM BELOW, SHOWING VALVE TOWER TO RIGHT. VIEW FACING NORTH - Schofield Barracks Military Reservation, Ku Tree Reservoir, Valve Tower Foot Bridge, Kalakoa Stream, East Range, Wahiawa, Honolulu County, HI

  2. Plans: Poop Deck, Boat Deck, Housetop, Bridge Deck, Upper Bridge ...

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

    Plans: Poop Deck, Boat Deck, Housetop, Bridge Deck, Upper Bridge Deck, Navigating Bridge, Forecastle Deck, Upper Deck, Second Deck and Hold - Saugatuck, James River Reserve Fleet, Newport News, Newport News, VA

  3. GOETHALS BRIDGE FROM NORTH SIDE OVER ARTHUR KILL. RAILROAD BRIDGE ...

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

    GOETHALS BRIDGE FROM NORTH SIDE OVER ARTHUR KILL. RAILROAD BRIDGE IN FOREGROUND - Goethals Bridge, Spanning Arthur Kill from New Jersey to Staten Island, Staten Island (subdivision), Richmond County, NY

  4. 1. VIEW OF SWING BRIDGE FROM KEDZIE AVENUE BRIDGE, LOOKING ...

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

    1. VIEW OF SWING BRIDGE FROM KEDZIE AVENUE BRIDGE, LOOKING EAST. - Chicago, Madison & Northern Railroad, Sanitary & Ship Canal Bridge, Spanning Sanitary & Ship Canal, east of Kedzie Avenue, Chicago, Cook County, IL

  5. 18. SPRING STREET BRIDGE AND BROADWAY BRIDGE AT CENTER. LOOKING ...

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

    18. SPRING STREET BRIDGE AND BROADWAY BRIDGE AT CENTER. LOOKING NORTHWEST. NOTE ELYSIAN PARK AT CENTER REAR. ARROYO SECO FREEWAY AT RIGHT REAR - Los Angeles River Bridges, Los Angeles, Los Angeles County, CA

  6. LODGEPOLE BRIDGE, FACING SOUTHEAST Generals Highway, Lodge Pole Bridge, ...

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

    LODGEPOLE BRIDGE, FACING SOUTHEAST - Generals Highway, Lodge Pole Bridge, Spanning Marble Fork of Kaweah River, approximately 21 miles northwest of Ash Mountain Entrance, Three Rivers, Tulare County, CA

  7. LODGEPOLE BRIDGE, FACING NORTHWEST Generals Highway, Lodge Pole Bridge, ...

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

    LODGEPOLE BRIDGE, FACING NORTHWEST - Generals Highway, Lodge Pole Bridge, Spanning Marble Fork of Kaweah River, approximately 21 miles northwest of Ash Mountain Entrance, Three Rivers, Tulare County, CA

  8. Precision bolometer bridge

    NASA Technical Reports Server (NTRS)

    White, D. R.

    1968-01-01

    Prototype precision bolometer calibration bridge is manually balanced device for indicating dc bias and balance with either dc or ac power. An external galvanometer is used with the bridge for null indication, and the circuitry monitors voltage and current simultaneously without adapters in testing 100 and 200 ohm thin film bolometers.

  9. Active-bridge oscillator

    DOEpatents

    Wessendorf, Kurt O. (Albuquerque, NM)

    2001-01-01

    An active bridge oscillator is formed from a differential amplifier where positive feedback is a function of the impedance of one of the gain elements and a relatively low value common emitter resistance. This use of the nonlinear transistor parameter h stabilizes the output and eliminates the need for ALC circuits common to other bridge oscillators.

  10. Bryce Canyon Natural Bridge

    USGS Multimedia Gallery

    The Bryce Canyon Natural Bridge. Technically, this is not a natural bridge, which forms when running water erodes a tunnel into a rock formation. Instead, this is a natural arch, similar to the ones in nearby Arches National Park. Bryce Canyon is a unique sandstone formation in southern Utah. It is...

  11. STEM Bridge Scholarship Program

    E-print Network

    Virginia Tech

    2015-2016 STEM Bridge Scholarship Program Virginia Space Grant Consortium (VSGC) provides renewable STEM Bridge Scholarships of $1,000 to sophomore students from any federally recognized minority group enrolled full-time in a program of study in science, technology, engineering, or math (STEM) at one

  12. Modelling a Suspension Bridge.

    ERIC Educational Resources Information Center

    Rawlins, Phil

    1991-01-01

    The quadratic function can be modeled in real life by a suspension bridge that supports a uniform weight. This activity uses concrete models and computer generated graphs to discover the mathematical model of the shape of the main cable of a suspension bridge. (MDH)

  13. Support Column of Bridge

    USGS Multimedia Gallery

    Support column of bridge across Struve Slough, Highway 1. Enlargement of hole where support enters the ground is an effect of lateral shaking, which caused the concrete to break up where the column joined the bridge and was instrumental in the roadbed collapse....

  14. Virtual Bridge Design Challenge

    ERIC Educational Resources Information Center

    Mitts, Charles R.

    2013-01-01

    This design/problem-solving activity challenges students to design a replacement bridge for one that has been designated as either structurally deficient or functionally obsolete. The Aycock MS Technology/STEM Magnet Program Virtual Bridge Design Challenge is an authentic introduction to the engineering design process. It is a socially relevant…

  15. Dissociable Influences of Skewness and Valence on Economic Choice and Neural Activity

    E-print Network

    Wright, Nicholas

    to positive skew (i.e. a small chance of a particularly good outcome) help explain gambling [5]. How of potential outcomes (i.e. skewness), and whether those potential outcomes reflect gains or losses (i Value-based decision-making is influenced by risk in potential outcomes, and also by whether those

  16. GC skew is a conserved property of unmethylated CpG island promoters across vertebrates.

    PubMed

    Hartono, Stella R; Korf, Ian F; Chédin, Frédéric

    2015-11-16

    GC skew is a measure of the strand asymmetry in the distribution of guanines and cytosines. GC skew favors R-loops, a type of three stranded nucleic acid structures that form upon annealing of an RNA strand to one strand of DNA, creating a persistent RNA:DNA hybrid. Previous studies show that GC skew is prevalent at thousands of human CpG island (CGI) promoters and transcription termination regions, which correspond to hotspots of R-loop formation. Here, we investigated the conservation of GC skew patterns in 60 sequenced chordates genomes. We report that GC skew is a conserved sequence characteristic of the CGI promoter class in vertebrates. Furthermore, we reveal that promoter GC skew peaks at the exon 1/ intron1 junction and that it is highly correlated with gene age and CGI promoter strength. Our data also show that GC skew is predictive of unmethylated CGI promoters in a range of vertebrate species and that it imparts significant DNA hypomethylation for promoters with intermediate CpG densities. Finally, we observed that terminal GC skew is conserved for a subset of vertebrate genes that tend to be located significantly closer to their downstream neighbors, consistent with a role for R-loop formation in transcription termination. PMID:26253743

  17. COMPENSATION OF FAST KICKER ROLLS WITH SKEW QUADRUPOLES

    SciTech Connect

    Pinayev, I.

    2011-03-28

    The development of the third generation light sources lead to the implementation of the top-up operation, when injection occurs while users collect data. The beam excursions due to the non-closure of the injection bump can spoil the data and need to be suppressed. In the horizontal plane compensation can be achieved by adjusting timing and kick amplitudes. The rolls of the kicker magnets create non-closure in the vertical plane and usually there is no means for correction. In the paper we describe proposed compensation scheme utilizing two skew quadrupoles placed inside the injection bump. The third generation light sources implement top-up operation firstly introduced at Advanced Photon Source. In this mode the circulating beam current is supported near constant by frequent injection of small charge, while photon beam is delivered for users. The beam perturbations caused by the mismatched injection bump can provide undesired noise in the user data. Usually the injection trigger is distributed to the users end stations so that those affected would be able to blank data acquisition. Nevertheless, as good operational practice such transients should be suppressed as much as possible. In the horizontal plane (which is commonly used for injection) one can adjust individual kicker strength as well as trigger delay while observing motion of the stored beam centroid. In the vertical plane such means are unavailable in the most cases. The possible solutions include dedicated weak vertical kickers and motorized adjustment of the roll angle of the injection kickers. Both abovementioned approaches are expensive and can significantly deteriorate reliability. We suggest two employ two skew quadrupoles (to correct both angle and position) placed inside the injection bump. In this case the beam position itself serves as measure of the kicker strength (assuming that kickers are well matched) and vertical kicks from the skew quadrupoles will be self synchronized with injection bump. In this paper we will consider the case when injection hardware (kickers and septa) are located in the same straight. Such an approach simplifies consideration but it can be generalized.

  18. Cracked shells under skew-symmetric loading. [Reissner theory

    NASA Technical Reports Server (NTRS)

    Delale, F.

    1981-01-01

    The general problem of a shell containing a through crack in one of the principal planes of curvature and under general skew-symmetric loading is considered. By employing a Reissner type shell theory which takes into account the effect of transverse shear strains, all boundary conditions on the crack surfaces are satisfied separately. Consequently, unlike those obtained from the classical shell theory, the angular distributions of the stress components around the crack tips are shown to be identical to the distributions obtained from the plane and anti-plane elasticity solutions. Results are given for axially and circumferentially cracked cylindrical shells, spherical shells, and toroidal shells under uniform in-plane shearing, out of plane shearing, and torsion. The problem is formulated for specially orthostropic materials, therefore, the effect of orthotropy on the results is also studied.

  19. Constraints on the skewness coefficient of symmetric nuclear matter

    E-print Network

    Bao-Jun Cai; Lie-Wen Chen

    2014-02-18

    Within the nonlinear relativistic mean field model, we show that both the pressure of symmetric nuclear matter at supra-saturation densities and the maximum mass of neutron stars are sensitive to the skewness coefficient $J_0$ of symmetric nuclear matter. Using experimental constraints on the pressure of symmetric nuclear matter at supra-saturation densities from flow data in heavy ion collisions and the astrophysical observation of a large mass neutron star PSR J0348+0432, with the former favoring a smaller $J_0$ while the latter a larger $J_0$, we extract a constraint of $-494 MeV \\leq J_0 \\leq -10 MeV$. This constraint is compared with the results obtained in other analyses.

  20. Restoring the skew quadrupole moment in the Tevatron dipoles

    SciTech Connect

    Harding, D.J.; Bauer, P.C.; Blowers, J.N.; DiMarco, J.; Glass, H.D.; Hanft, R.W.; Carson, J.A.; Robotham, W.F.; Tartaglia, M.A.; Tompkins, J.C.; Velev, G.; /Fermilab

    2005-05-01

    In early 2003 it was realized that mechanical changes in the Tevatron dipoles had led to a deterioration of the magnetic field quality that was hindering operation of the accelerator. After extensive study, a remediation program was started in late 2003 that will continue through 2005. The mechanical and magnetic effects are discussed. The readjustment process and experience are reported, along with other observations on aging magnets. In January 2003 two lines of inquiry converged, leading to the recognition that the severe betatron coupling that was hindering operation of the Tevatron could be explained by a systematic shift on the skew quadrupole field in the dipole magnets of the same size expected from observed mechanical movement of the coils inside the magnet yokes [1]. This paper reports on subsequent magnet studies that were conducted in parallel with additional beam studies and accelerator modeling [2] exploring the feasibility of the eventual remediation effort [3].

  1. Study of rolling element dynamic interactions with separator and raceway paths. Roller skewing measurements in roller bearings

    NASA Technical Reports Server (NTRS)

    Nypan, L. J.

    1980-01-01

    Measurements of roller skewing in a 118 mm bore roller bearing operating at shaft speeds to 12000 rpm are reported. High speed motion pictures of a modified roller were taken through a derotation prism to record skewing as the roller moved through loaded and unloaded regions of the bearing. Subsequent frame by frame measurement of the photographic film provided information on roller skewing. Radial and tangential skew amplitudes of .4 to .5 degrees were observed with .5 degree misalignment.

  2. The floating water bridge The floating water bridge

    E-print Network

    Podgornik, Rudolf

    experiments were performed under normal laboratory atmosphere using triply distilled water. High speed-05) was used. #12;The floating water bridge To record the surface temperature along the water bridgeThe floating water bridge The floating water bridge Elmar C. Fuchs1 , Jakob Woisetschläger2 , Karl

  3. VIEW OF BRIDGE, LOOKING SOUTHWEST, WITH SOUTHERN PACIFIC RAILROAD BRIDGE ...

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

    VIEW OF BRIDGE, LOOKING SOUTHWEST, WITH SOUTHERN PACIFIC RAILROAD BRIDGE IN BACKGROUND. THE PAVEMENT OF THE NORTH APPROACH IS SEEN BURIED ON THE RIGHT. ROADWAY (CENTER) CROSSES THE USUALLY DRY CHANNEL OF THE SALT RIVER. A BALUSTRADE OF THE MILL AVENUE BRIDGE IS SEEN AT THE LOWER LEFT CORNER - Ash Avenue Bridge, Spanning Salt River at Foot of Ash Avenue, Tempe, Maricopa County, AZ

  4. 29. BRIDGE NO. 13 APRON AND BRIDGE HINGE JOINT AND ...

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

    29. BRIDGE NO. 13 APRON AND BRIDGE HINGE JOINT AND BRIDGE SUSPENSION SYSTEM (OLDER STYLE) SHOWING EYEBAR AND CABLE CONNECTIONS. LOOKING WEST. - Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, Upper New York Bay, Jersey City, Hudson County, NJ

  5. 28. BRIDGE NO. 9 APRON AND BRIDGE HINGE JOINT AND ...

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

    28. BRIDGE NO. 9 APRON AND BRIDGE HINGE JOINT AND BRIDGE SUSPENSION SYSTEM SHOWING EYEBAR AND CABLE CONNECTIONS. LOOKING WEST. - Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, Upper New York Bay, Jersey City, Hudson County, NJ

  6. Torsional instability in suspension bridges: the Tacoma Narrows Bridge case

    E-print Network

    Torsional instability in suspension bridges: the Tacoma Narrows Bridge case Gianni ARIOLI ­ Filippo explanations for the torsional instability of suspension bridges have been somehow criticised and none of them is unanimously accepted by the scientific community. We suggest a new nonlinear model for a suspension bridge

  7. 47 CFR 80.331 - Bridge-to-bridge communication procedure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Bridge-to-bridge communication procedure. 80...Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED...Bridge-to-bridge communication procedure. ...frequency must conduct communications in a format...

  8. Modulation of Root Skewing in Arabidopsis by Apyrases and Extracellular ATP.

    PubMed

    Yang, Xingyan; Wang, Bochu; Farris, Ben; Clark, Greg; Roux, Stanley J

    2015-11-01

    When plant primary roots grow along a tilted surface that is impenetrable, they can undergo a slanted deviation from the direction of gravity called skewing. Skewing is induced by touch stimuli which the roots experience as they grow along the surface. Touch stimuli also induce the release of extracellular ATP (eATP) into the plant's extracellular matrix, and two apyrases (NTPDases) in Arabidopsis, APY1 and APY2, can help regulate the concentration of eATP. The primary roots of seedlings overexpressing APY1 show less skewing than wild-type plants. Plants suppressed in their expression of APY1 show more skewing than wild-type plants. Correspondingly, chemical inhibition of apyrase activity increased skewing in mutants and wild-type roots. Exogenous application of ATP or ATP?S also increased skewing in wild-type roots, which could be blocked by co-incubation with a purinergic receptor antagonist. These results suggest a model in which gradients of eATP set up by differential touch stimuli along roots help direct skewing in roots growing along an impenetrable surface. PMID:26412783

  9. Log Pearson type 3 quantile estimators with regional skew information and low outlier adjustments

    USGS Publications Warehouse

    Griffis, V.W.; Stedinger, J.R.; Cohn, T.A.

    2004-01-01

    [1] The recently developed expected moments algorithm (EMA) [Cohn et al., 1997] does as well as maximum likelihood estimations at estimating log-Pearson type 3 (LP3) flood quantiles using systematic and historical flood information. Needed extensions include use of a regional skewness estimator and its precision to be consistent with Bulletin 17B. Another issue addressed by Bulletin 17B is the treatment of low outliers. A Monte Carlo study compares the performance of Bulletin 17B using the entire sample with and without regional skew with estimators that use regional skew and censor low outliers, including an extended EMA estimator, the conditional probability adjustment (CPA) from Bulletin 17B, and an estimator that uses probability plot regression (PPR) to compute substitute values for low outliers. Estimators that neglect regional skew information do much worse than estimators that use an informative regional skewness estimator. For LP3 data the low outlier rejection procedure generally results in no loss of overall accuracy, and the differences between the MSEs of the estimators that used an informative regional skew are generally modest in the skewness range of real interest. Samples contaminated to model actual flood data demonstrate that estimators which give special treatment to low outliers significantly outperform estimators that make no such adjustment.

  10. Onyx Bridg e Volcanology

    E-print Network

    Carso n Oregon Onyx Bridg e Cascad e Willamette University etuhcseDs BEECH Boyn itseuHs Volcanology (Turns into Franklin Blvd) 6. Continue on Franklin Blvd until you reach Onyx. 7. Turn right into the Onyx

  11. Enhanced responsivity with skew ray excitation of reflection- and transmission-type refractometric sensors.

    PubMed

    Chen, George Y; Codemard, Christophe A; Lewis, Richard J; Jankowski, Lukasz; Chan, Jaclyn S; Gorman, Philip M; Zervas, Michalis N

    2014-07-01

    The responsivity of optical fibers to refractive index can be enhanced using high-order skew rays compared with using meridional rays. Skew rays can have a much higher number of reflections with increased interaction length along the core-cladding interface, which gives rise to stronger interactions with the external medium. Reflection/transmission-type refractometric sensors based on twin-coupled-core and multimode fibers showed one/two orders of magnitude increase in responsivity with skew ray excitation. The responsivity and sensitivity for the two types are ~2000%/RIU, ~1400%/RIU, and 4.9×10????RIU, 7.0×10????RIU, respectively. PMID:24978746

  12. Estimating generalized skew of the log-Pearson Type III distribution for annual peak floods in Illinois

    USGS Publications Warehouse

    Oberg, Kevin A.; Mades, Dean M.

    1987-01-01

    Four techniques for estimating generalized skew in Illinois were evaluated: (1) a generalized skew map of the US; (2) an isoline map; (3) a prediction equation; and (4) a regional-mean skew. Peak-flow records at 730 gaging stations having 10 or more annual peaks were selected for computing station skews. Station skew values ranged from -3.55 to 2.95, with a mean of -0.11. Frequency curves computed for 30 gaging stations in Illinois using the variations of the regional-mean skew technique are similar to frequency curves computed using a skew map developed by the US Water Resources Council (WRC). Estimates of the 50-, 100-, and 500-yr floods computed for 29 of these gaging stations using the regional-mean skew techniques are within the 50% confidence limits of frequency curves computed using the WRC skew map. Although the three variations of the regional-mean skew technique were slightly more accurate than the WRC map, there is no appreciable difference between flood estimates computed using the variations of the regional-mean technique and flood estimates computed using the WRC skew map. (Peters-PTT)

  13. Statistics on Cannabis Users Skew Perceptions of Cannabis Use

    PubMed Central

    Burns, Rachel M.; Caulkins, Jonathan P.; Everingham, Susan S.; Kilmer, Beau

    2013-01-01

    Collecting information about the prevalence of cannabis use is necessary but not sufficient for understanding the size, dynamics, and outcomes associated with cannabis markets. This paper uses two data sets describing cannabis consumption in the United States and Europe to highlight (1) differences in inferences about sub-populations based on the measure used to quantify cannabis-related activity; (2) how different measures of cannabis-related activity can be used to more accurately describe trends in cannabis usage over time; and (3) the correlation between frequency of use in the past-month and average grams consumed per use-day. Key findings: focusing on days of use instead of prevalence shows substantially greater increases in U.S. cannabis use in recent years; however, the recent increase is mostly among adults, not youth. Relatively more rapid growth in use days also occurred among the college-educated and Hispanics. Further, data from a survey conducted in seven European countries show a strong positive correlation between frequency of use and quantity consumed per day of use, suggesting consumption is even more skewed toward the minority of heavy users than is suggested by days-of-use calculations. PMID:24223560

  14. Skew redundant MEMS IMU calibration using a Kalman filter

    NASA Astrophysics Data System (ADS)

    Jafari, M.; Sahebjameyan, M.; Moshiri, B.; Najafabadi, T. A.

    2015-10-01

    In this paper, a novel calibration procedure for skew redundant inertial measurement units (SRIMUs) based on micro-electro mechanical systems (MEMS) is proposed. A general model of the SRIMU measurements is derived which contains the effects of bias, scale factor error and misalignments. For more accuracy, the effect of lever arms of the accelerometers to the center of the table are modeled and compensated in the calibration procedure. Two separate Kalman filters (KFs) are proposed to perform the estimation of error parameters for gyroscopes and accelerometers. The predictive error minimization (PEM) stochastic modeling method is used to simultaneously model the effect of bias instability and random walk noise on the calibration Kalman filters to diminish the biased estimations. The proposed procedure is simulated numerically and has expected experimental results. The calibration maneuvers are applied using a two-axis angle turntable in a way that the persistency of excitation (PE) condition for parameter estimation is met. For this purpose, a trapezoidal calibration profile is utilized to excite different deterministic error parameters of the accelerometers and a pulse profile is used for the gyroscopes. Furthermore, to evaluate the performance of the proposed KF calibration method, a conventional least squares (LS) calibration procedure is derived for the SRIMUs and the simulation and experimental results compare the functionality of the two proposed methods with each other.

  15. New understanding on the contribution of the central otolithic system to eye movement and skew deviation.

    PubMed

    Wong, A M F

    2015-02-01

    The otolith organs consist of the utricle and saccule. The utricle mediates the utriculo-ocular reflex by detecting horizontal head translation and static head tilt. Skew deviation is a vertical strabismus caused by imbalance of the utriculo-ocular reflex pathway and is commonly caused by lesions in the brainstem or cerebellum. It is associated with abnormal utriculo-ocular reflexes including asymmetric reduction of the translational vestibulo-ocular and ocular counterroll responses. Skew deviation is also associated with head position-dependent changes in ocular torsion and vertical strabismus. The reduction in ocular torsion and vertical strabismus when changing from an upright to supine position in skew deviation allows us to devise a new bedside 'upright-supine test' to differentiate skew deviation from fourth nerve palsy and other causes of vertical strabismus. PMID:25323854

  16. On Good Matrices and Skew Hadamard Gene Awyzio and Jennifer Seberry

    E-print Network

    Seberry, Jennifer

    and similar matrices such as Hadamard ma- trices, weighing matrices, conference matrices and D-optimal designs matrices. Good matrices were designed to plug into the Seberry-Williamson array to give skew

  17. Skewness in large-scale structure and non-Gaussian initial conditions

    NASA Technical Reports Server (NTRS)

    Fry, J. N.; Scherrer, Robert J.

    1994-01-01

    We compute the skewness of the galaxy distribution arising from the nonlinear evolution of arbitrary non-Gaussian intial conditions to second order in perturbation theory including the effects of nonlinear biasing. The result contains a term identical to that for a Gaussian initial distribution plus terms which depend on the skewness and kurtosis of the initial conditions. The results are model dependent; we present calculations for several toy models. At late times, the leading contribution from the initial skewness decays away relative to the other terms and becomes increasingly unimportant, but the contribution from initial kurtosis, previously overlooked, has the same time dependence as the Gaussian terms. Observations of a linear dependence of the normalized skewness on the rms density fluctuation therefore do not necessarily rule out initially non-Gaussian models. We also show that with non-Gaussian initial conditions the first correction to linear theory for the mean square density fluctuation is larger than for Gaussian models.

  18. Dog Bridge, view of the deck of the bridge and ...

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

    Dog Bridge, view of the deck of the bridge and rails looking from Linden Lane - National Park Seminary, Bounded by Capitol Beltway (I-495), Linden Lane, Woodstove Avenue, & Smith Drive, Silver Spring, Montgomery County, MD

  19. 4. VIEW OF SILVER BRIDGE (ST. MARY'S BRIDGE), CARRYING COUNTY ...

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

    4. VIEW OF SILVER BRIDGE (ST. MARY'S BRIDGE), CARRYING COUNTY ROAD OVER SOURIS RIVER NEAR SOUTH END OF REFUGE, LOOKING NORTHEAST - Upper Souris National Wildlife Refuge Dams, Souris River Basin, Foxholm, Ward County, ND

  20. Genetic Architecture of Skewed X Inactivation in the Laboratory Mouse

    PubMed Central

    Calaway, John D.; Lenarcic, Alan B.; Didion, John P.; Wang, Jeremy R.; Searle, Jeremy B.; McMillan, Leonard; Valdar, William; Pardo-Manuel de Villena, Fernando

    2013-01-01

    X chromosome inactivation (XCI) is the mammalian mechanism of dosage compensation that balances X-linked gene expression between the sexes. Early during female development, each cell of the embryo proper independently inactivates one of its two parental X-chromosomes. In mice, the choice of which X chromosome is inactivated is affected by the genotype of a cis-acting locus, the X-chromosome controlling element (Xce). Xce has been localized to a 1.9 Mb interval within the X-inactivation center (Xic), yet its molecular identity and mechanism of action remain unknown. We combined genotype and sequence data for mouse stocks with detailed phenotyping of ten inbred strains and with the development of a statistical model that incorporates phenotyping data from multiple sources to disentangle sources of XCI phenotypic variance in natural female populations on X inactivation. We have reduced the Xce candidate 10-fold to a 176 kb region located approximately 500 kb proximal to Xist. We propose that structural variation in this interval explains the presence of multiple functional Xce alleles in the genus Mus. We have identified a new allele, Xcee present in Mus musculus and a possible sixth functional allele in Mus spicilegus. We have also confirmed a parent-of-origin effect on X inactivation choice and provide evidence that maternal inheritance magnifies the skewing associated with strong Xce alleles. Based on the phylogenetic analysis of 155 laboratory strains and wild mice we conclude that Xcea is either a derived allele that arose concurrently with the domestication of fancy mice but prior the derivation of most classical inbred strains or a rare allele in the wild. Furthermore, we have found that despite the presence of multiple haplotypes in the wild Mus musculus domesticus has only one functional Xce allele, Xceb. Lastly, we conclude that each mouse taxa examined has a different functional Xce allele. PMID:24098153

  1. Skewed birth sex ratio and premature mortality in elephants.

    PubMed

    Saragusty, Joseph; Hermes, Robert; Göritz, Frank; Schmitt, Dennis L; Hildebrandt, Thomas B

    2009-10-01

    Sex allocation theories predict equal offspring number of both sexes unless differential investment is required or some competition exists. Left undisturbed, elephants reproduce well and in approximately even numbers in the wild. We report an excess of males are born and substantial juvenile mortality occurs, perinatally, in captivity. Studbook data on captive births (CB, n=487) and premature deaths (PD, <5 years of age; n=164) in Asian and African elephants in Europe and North America were compared with data on Myanmar timber (Asian) elephants (CB, n=3070; PD, n=738). Growth in CB was found in three of the captive populations. A significant excess of male births occurred in European Asian elephants (ratio: 0.61, P=0.044) and in births following artificial insemination (0.83, P=0.003), and a numerical inclination in North American African elephants (0.6). While juvenile mortality in European African and Myanmar populations was 21-23%, it was almost double (40-45%) in all other captive populations. In zoo populations, 68-91% of PD were within 1 month of birth with stillbirth and infanticide being major causes. In Myanmar, 62% of juvenile deaths were at >6 months with maternal insufficient milk production, natural hazards and accidents being the main causes. European Asian and Myanmar elephants PD was biased towards males (0.71, P=0.024 and 0.56, P<0.001, respectively). The skewed birth sex ratio and high juvenile mortality hinder efforts to help captive populations become self-sustaining. Efforts should be invested to identify the mechanism behind these trends and seek solutions for them. PMID:19058933

  2. 18. GRAYS RIVER BRIDGE PLAN, DATED 1905 (Original bridge plan ...

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

    18. GRAYS RIVER BRIDGE PLAN, DATED 1905 (Original bridge plan was lost after the plan was photographed.) this photograph is an 8x10-inch enlargement from a 4x5-inch negative) - Grays River Covered Bridge, Worrel Road spanning Grays River, Grays River, Wahkiakum County, WA

  3. 50. INTERIOR OF BRIDGE SUSPENSION STRUCTURE ABOVE BRIDGE NOS. 10 ...

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

    50. INTERIOR OF BRIDGE SUSPENSION STRUCTURE ABOVE BRIDGE NOS. 10 AND 9 SHOWING CABLE COUNTERWEIGHT SYSTEM AND SCREW-TYPE VERTICAL ADJUSTMENT MACHINERY (LIFTING SCREWS). LOOKING NORTH. - Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, Upper New York Bay, Jersey City, Hudson County, NJ

  4. 16. LOG AND PLANK BRIDGE ON ACCESS ROAD NEAR BRIDGE ...

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

    16. LOG AND PLANK BRIDGE ON ACCESS ROAD NEAR BRIDGE SITE; SAME STRUCTURE AS SHOWN IN PHOTO #12. ZION NP NEGATIVE NO. 967 ZIO. - Zion-Mount Carmel Highway, Virgin River Bridge, Spanning North Fork of Virgin River on Zion-Mount Carmel Highway, Springdale, Washington County, UT

  5. Bike/ped bridge CAMPUSDRIVEWEST

    E-print Network

    I Bike/ped bridge Bike/ped bridge Bike/ped underpass ELCAM ELCAM INO REAL GALVEZST SERRA MALL CAM Center Safeway Munger Y2E2 Parking & Transportation Services (P&TS) Montag Hall Stock Farm lot Parking

  6. BUILDING "BRIDGES" WITH QUALITY ASSURANCE

    EPA Science Inventory

    The papr describes how, rather than building "bridges" across centuries, quality assurance (QA) personnel have the opportunity to build bridges across technical disciplines, between public and private organizations, and between different QA groups. As reviewers and auditors of a...

  7. Bryce Canyon Natural Bridge

    USGS Multimedia Gallery

    Bryce Canyon's Natural Bridge is technically a natural arch, similar to those in the nearby Arches National Park. Bryce Canyon is a unique sandstone formation in southern Utah. It is home to a large number of hoodoos, which are oddly shaped pillars of rock that formed due to different erosion rates...

  8. Building Migratory Bridges

    ERIC Educational Resources Information Center

    Roy, Michael; Doss, Laurie K.

    2007-01-01

    The Building Migratory Bridges (BOMB) program--a collaboration between the Marvel wood School and Audubon Sharon in Connecticut and Conservation Research Education Action (CR EA), a U.S. not-for-profit in Panama--uses nontropical migratory bird research in the United States and Panama to demonstrate how negative environmental impacts in one…

  9. The Bridge to Somewhere

    ERIC Educational Resources Information Center

    Lum, Lydia

    2009-01-01

    Since its inception in 2000, Pan-Asian American Community House's (PAACH's) education mission has bridged Asian-American studies to student life. PAACH initiatives have helped spread Asian-American diaspora to thousands of students at the University of Pennsylvania. They have also helped students determine for themselves what it means to be a…

  10. Bridges With Biology, Neuroscience,

    E-print Network

    Ruvinsky, Ilya

    , and aggression; to group processes such as social facilitation, cooper- ation and competition, equity, leadership the history of social psychology, we can witness continuity and change in the degree to which various bridges social psychology has been strongly connected to the study of biological sys- tems, to animal research

  11. Virtual Bridge Design

    ERIC Educational Resources Information Center

    Bisogno, Janet; JeanPierre, Bobby

    2008-01-01

    The West Point Bridge Design (WPBD) building project engages students in project-based learning by giving them a real-life problem to solve. By using technology, students are able to become involved in solving problems that they normally would not encounter. Involvement with interactive websites, such as WPBD, assists students in using…

  12. Bridging the Gap?

    ERIC Educational Resources Information Center

    Salter, Colin

    2009-01-01

    The political context of the conversion of the Historic Tramway Bridge, adjacent to Sandon Point in Bulli (NSW, Australia), and how this was exploited to serve predetermined ends, illustrates that technologies can be designed to have particular social (and political) effects. Through reflection on this relatively small engineering project, this…

  13. Bridging the Gap.

    ERIC Educational Resources Information Center

    Kroto, Joseph J.

    1988-01-01

    Describes interdisciplinary activities with real-world applications ranging from science to mathematics to technology. Cites the study and construction of model bridges as a way for students to learn about engineering concepts and some of their relationships. States that the exercise enhanced teacher cooperation between the different fields. (RT)

  14. Onyx Bridg e Volcanology

    E-print Network

    Carso n Oregon Onyx Bridg e Cascad e Willamette University etuhcseDs BEECH Boyn itseuHs Volcanology on Franklin Blvd until you reach Onyx. 7. Turn right into the Onyx lot, then left towards the end of the lot

  15. Bridging the Generation Gap

    ERIC Educational Resources Information Center

    Johnson, Susan Moore; Kardos, Susan M.

    2005-01-01

    The lack of instructional continuity in schools negates every effort of principals to provide an environment where all students would be successful. One solution could be to bridge the gap between the professional knowledge and skills of experienced teachers and the energy and fresh ideas of new recruits so that the latter are provided support…

  16. Quantum Bidding in Bridge

    NASA Astrophysics Data System (ADS)

    Muhammad, Sadiq; Tavakoli, Armin; Kurant, Maciej; Paw?owski, Marcin; ?ukowski, Marek; Bourennane, Mohamed

    2014-04-01

    Quantum methods allow us to reduce communication complexity of some computational tasks, with several separated partners, beyond classical constraints. Nevertheless, experimental demonstrations of this have thus far been limited to some abstract problems, far away from real-life tasks. We show here, and demonstrate experimentally, that the power of reduction of communication complexity can be harnessed to gain an advantage in a famous, immensely popular, card game—bridge. The essence of a winning strategy in bridge is efficient communication between the partners. The rules of the game allow only a specific form of communication, of very low complexity (effectively, one has strong limitations on the number of exchanged bits). Surprisingly, our quantum technique does not violate the existing rules of the game (as there is no increase in information flow). We show that our quantum bridge auction corresponds to a biased nonlocal Clauser-Horne-Shimony-Holt game, which is equivalent to a 2?1 quantum random access code. Thus, our experiment is also a realization of such protocols. However, this correspondence is not complete, which enables the bridge players to have efficient strategies regardless of the quality of their detectors.

  17. Bridging the Gaps.

    ERIC Educational Resources Information Center

    Netzer, Greg

    1995-01-01

    Discusses a model water quality monitoring project, Project Bridge, established to train minority girls about to enter eighth grade in scientific procedures followed by hands-on experimentation. Students spent a week monitoring water in an urban stream and analyzing results. (LZ)

  18. USGS Gage At Covered Bridge

    USGS Multimedia Gallery

    This photograph shows Lowe's Bridge off ME-15 in Guilford, Maine, spanning the Piscataquis River. USGS gaging station 01031500 is located on the downstream side of the bridge. The original bridge, built in 1857, washed away in the flood of 1987, and was rebuilt on the original abutments in 1990....

  19. SURROGATE BRIDGE FREEZING SRDJAN JANKOVIC

    E-print Network

    SURROGATE BRIDGE FREEZING SENSORS by SRDJAN JANKOVIC Bachelor of Science University of Belgrade: Stillwater, Oklahoma Title of Study: SURROGATE BRIDGE FREEZING SENSORS Pages in Study: 121 Candidate of this study was to design and test surrogate bridge freezing sensors in order to provide training data

  20. Intracolonial genetic variation affects reproductive skew and colony productivity during colony foundation in a parthenogenetic termite

    PubMed Central

    2014-01-01

    Background In insect societies, intracolonial genetic variation is predicted to affect both colony efficiency and reproductive skew. However, because the effects of genetic variation on these two colony characteristics have been tested independently, it remains unclear whether they are affected by genetic variation independently or in a related manner. Here we test the effect of genetic variation on colony efficiency and reproductive skew in a rhinotermitid termite, Reticulitermes speratus, a species in which female-female pairs can facultatively found colonies. We established colonies using two types of female-female pairs: colonies founded by sisters (i.e., sister-pair colonies) and those founded by females from different colonies (i.e., unrelated-pair colonies). Colony growth and reproductive skew were then compared between the two types of incipient colonies. Results At 15 months after colony foundation, unrelated-pair colonies were larger than sister-pair colonies, although the caste ratio between workers and nymphs, which were alternatively differentiated from young larvae, did not differ significantly. Microsatellite DNA analyses of both founders and their parthenogenetically produced offspring indicated that, in both sister-pair and unrelated-pair colonies, there was no significant skew in the production of eggs, larvae, workers and soldiers. Nymph production, however, was significantly more skewed in the sister-pair colonies than in unrelated-pair colonies. Because nymphs can develop into winged adults (alates) or nymphoid reproductives, they have a higher chance of direct reproduction than workers in this species. Conclusions Our results support the idea that higher genetic variation among colony members could provide an increase in colony productivity, as shown in hymenopteran social insects. Moreover, this study suggests that low genetic variation (high relatedness) between founding females increases reproductive skew via one female preferentially channeling her relatives along the reproductive track. This study thus demonstrated that, in social insects, intracolonial genetic variation can simultaneously affect both colony efficiency and reproductive skew. PMID:25123355

  1. Effective step-skew method for cogging torque reduction in surface-mounted permanent magnet synchronous motor

    NASA Astrophysics Data System (ADS)

    Kim, Tae-Woo; Chang, Jung-Hwan

    2013-08-01

    This paper suggests an effective step-skew method to reduce the cogging torque of a surface-mounted permanent magnet synchronous motor (SPMSM). The main concept of the proposed method is to adjust each step length by considering the non-uniform air gap flux density distribution in the axial direction. The results show that the proposed step-skew method reduces the net cogging torque compared with the conventional step-skew method and is more effective for smaller stacking lengths and larger skew steps.

  2. Analysis of gamma-ray burst duration distribution using mixtures of skewed distributions

    E-print Network

    Mariusz Tarnopolski

    2015-12-09

    Two classes of GRBs have been confidently identified thus far and are prescribed to different physical scenarios -- NS-NS or NS-BH mergers, and collapse of massive stars, for short and long GRBs, respectively. A third, intermediate in duration class, was suggested to be present in previous catalogs, such as BATSE and $Swift$, based on statistical tests regarding a mixture of two or three log-normal distributions of $T_{90}$. However, this might possibly not be an adequate model. This paper investigates whether the distributions of $\\log T_{90}$ from BATSE, $Swift$, and $Fermi$ are described better by a mixture of skewed distributions rather than standard Gaussians. Mixtures of standard normal, skew-normal, sinh-arcsinh and alpha-skew-normal distributions are fitted using a maximum likelihood method. The preferred model is chosen based on the Akaike information criterion. It is found that mixtures of two skew-normal or two sinh-arcsinh distributions are more likely to describe the observed duration distribution of $Fermi$ than a mixture of three standard Gaussians, and that mixtures of two sinh-arcsinh or two skew-normal distributions are models competing with the conventional three-Gaussian in the case of BATSE and $Swift$. Based on statistical reasoning, existence of a third (intermediate) class of GRBs in $Fermi$ data is rejected, and it is shown that other phenomenological models may describe the observed $Fermi$, BATSE, and $Swift$ duration distributions at least as well as a mixture of standard normal distributions.

  3. Starving the competition: a proximate cause of reproductive skew in burying beetles (Nicrophorus vespilloides)

    PubMed Central

    Eggert, Anne-Katrin; Otte, Tobias; Müller, Josef K

    2008-01-01

    Proximate mechanisms underlying reproductive skew are obscure in many animals that breed communally. Here, we address causes of reproductive skew in brood-parasitic associations of burying beetles (Nicrophorus vespilloides). Male and female burying beetles feed and defend their larvae on buried carcasses. When several females locate the same small carcass, they engage in violent physical altercations. The subordinate then acts as an intraspecific brood parasite, laying eggs, but not providing care. The dominant female largely monopolizes access to the carcass; she alone provides parental care and her share of the brood is much larger than the subordinate's. On larger carcasses, subordinates have greater access to the carcass than on small ones, and reproductive skew is reduced. Differential fecundity, ovicide and larvicide have been suggested as causes of skew on small carcasses. Here, we report the results of the experiments pertaining to the first two of these potential mechanisms. Ovicide did not significantly contribute to reproductive skew on small carcasses, but differential fecundity did. Fecundity differences were due to dominance status, not body size per se. Fecundity differences disappeared when supplemental food was available, suggesting that reduced access to the carcass limits fecundity by causing nutritional deficiencies. Supplemental food prevented such nutritional deficiencies and allowed subordinates to produce as many eggs as dominants. Apparently, aggressive behaviour by dominants functions in the context of reproductive competition, limiting subordinate reproduction by preventing food intake on the carcass. PMID:18647719

  4. Electrical Actuation Technology Bridging

    NASA Astrophysics Data System (ADS)

    Hammond, Monica; Sharkey, John

    1993-05-01

    This document contains the proceedings of the NASA Electrical Actuation Technology Bridging (ELA-TB) Workshop held in Huntsville, Alabama, September 29-October 1, 1992. The workshop was sponsored by the NASA Office of Space Systems Development and Marshall Space Flight Center (MSFC). The workshop addressed key technologies bridging the entire field of electrical actuation including systems methodology, control electronics, power source systems, reliability, maintainability, and vehicle health management with special emphasis on thrust vector control (TVC) applications on NASA launch vehicles. Speakers were drawn primarily from industry with participation from universities and government. In addition, prototype hardware demonstrations were held at the MSFC Propulsion Laboratory each afternoon. Splinter sessions held on the final day afforded the opportunity to discuss key issues and to provide overall recommendations. Presentations are included in this document.

  5. Electrical Actuation Technology Bridging

    NASA Technical Reports Server (NTRS)

    Hammond, Monica (compiler); Sharkey, John (compiler)

    1993-01-01

    This document contains the proceedings of the NASA Electrical Actuation Technology Bridging (ELA-TB) Workshop held in Huntsville, Alabama, September 29-October 1, 1992. The workshop was sponsored by the NASA Office of Space Systems Development and Marshall Space Flight Center (MSFC). The workshop addressed key technologies bridging the entire field of electrical actuation including systems methodology, control electronics, power source systems, reliability, maintainability, and vehicle health management with special emphasis on thrust vector control (TVC) applications on NASA launch vehicles. Speakers were drawn primarily from industry with participation from universities and government. In addition, prototype hardware demonstrations were held at the MSFC Propulsion Laboratory each afternoon. Splinter sessions held on the final day afforded the opportunity to discuss key issues and to provide overall recommendations. Presentations are included in this document.

  6. Modeling the effects of wave skewness and beach cusps on littoral sand transport

    USGS Publications Warehouse

    Haas, K.A.; Check, L.A.; Hanes, D.M.

    2008-01-01

    A process-based numerical modeling system is utilized for predicting littoral sand transport. The intent is to examine conditions slightly more complex than linear waves impinging upon a plane beach. Two factors that we examine are wave skewness and longshore varying bathymetry. An empirical model is used for calculating the skewed bottom wave orbital velocity. The advection of sediment due to the skewed wave velocity is larger and in the direction of the waves, opposite to the results with sinusoidal wave velocities, due to the increase in the bottom shear stress under the wave crests. The model system is also applied to bathymetry containing beach cusps. When the wave field has relatively weak longshore wave power, the currents and the littoral transport exhibit significant longshore variability, thereby altering the overall mean littoral transport.

  7. Distribution of mean Doppler shift, spectral width, and skewness of coherent 50-MHz auroral radar backscatter

    SciTech Connect

    Watermann, J.; McNamara, A.G. ); Sofko, G.J.; Koehler, J.A. )

    1989-06-01

    Some 7,700 radio aurora spectra obtained from a six link 50-MHz CW radar network set up on the Canadian prairies were analyzed with respect to the distributions of mean Doppler shift, spectral width and skewness. A comparison with recently published SABRE results obtained at 153 MHz shows substantial differences in the distributions which are probably due to different experimental and geophysical conditions. The spectra are mostly broad with mean Doppler shifts close to zero (type II spectra). The typical groupings of type I and type III spectra are clearly identified. All types appear to be in general much more symmetric than those recorded with SABRE, and the skewness is only weakly dependent on the sign of the mean Doppler shift. Its distribution peaks near zero and shows a weak positive correlation with the type II Doppler shifts while the mostly positive type I Doppler shifts are slightly negatively correlated with the skewness.

  8. Gaudin-type models, non-skew-symmetric classical r-matrices and nested Bethe ansatz

    NASA Astrophysics Data System (ADS)

    Skrypnyk, T.

    2015-02-01

    We consider quantum integrable systems associated with the Lie algebra gl (n) and Cartan-invariant non-dynamical non-skew-symmetric classical r-matrices. We describe the sub-class of Cartan-invariant non-skew-symmetric r-matrices for which exists the standard procedure of the nested Bethe ansatz associated with the chain of embeddings gl (n) ? gl (n - 1) ? gl (n - 2) ? ⋯ ? gl (1). We diagonalize the corresponding quantum integrable systems by its means. We illustrate the obtained results by the examples of the generalized Gaudin systems with and without external magnetic field associated with three classes of non-dynamical non-skew-symmetric classical r-matrices.

  9. Generation of time histories with a specified auto spectral density, skewness, and kurtosis

    SciTech Connect

    Smallwood, D.O.

    1996-02-01

    Some dynamic environments are characterized by time histories that are not Gaussian. A more accurate simulation of these environments can be generated if a realization of a non Gaussian time history can be reproduced which has a specified auto spectral density (also called power spectral density) and a specified skewness and kurtosis (not necessarily the skewness and kurtosis of a Gaussian time history). The mean square of the waveform is reproduced if the spectrum is reproduced. Modern waveform reproduction techniques can be used to reproduce the realized waveform on an electrodynamic or electrohydraulic shaker. A method is presented for the generation of realizations of zero mean non Gaussian random time histories with a specified auto spectral density, skewness, and kurtosis. Kurtosis, defined in this paper as E[{chi}{sup 4}]/E{sup 2}[{chi}{sup 2}], greater than 3 can be realized. Realizations of the random process are generated with a generalization of shot noise.

  10. Perceived quality of wood images influenced by the skewness of image histogram

    NASA Astrophysics Data System (ADS)

    Katsura, Shigehito; Mizokami, Yoko; Yaguchi, Hirohisa

    2015-08-01

    The shape of image luminance histograms is related to material perception. We investigated how the luminance histogram contributed to improvements in the perceived quality of wood images by examining various natural wood and adhesive vinyl sheets with printed wood grain. In the first experiment, we visually evaluated the perceived quality of wood samples. In addition, we measured the colorimetric parameters of the wood samples and calculated statistics of image luminance. The relationship between visual evaluation scores and image statistics suggested that skewness and kurtosis affected the perceived quality of wood. In the second experiment, we evaluated the perceived quality of wood images with altered luminance skewness and kurtosis using a paired comparison method. Our result suggests that wood images are more realistic if the skewness of the luminance histogram is slightly negative.

  11. Scaled variance, skewness, and kurtosis near the critical point of nuclear matter

    NASA Astrophysics Data System (ADS)

    Vovchenko, V.; Anchishkin, D. V.; Gorenstein, M. I.; Poberezhnyuk, R. V.

    2015-11-01

    The van der Waals (VDW) equation of state predicts the existence of a first-order liquid-gas phase transition and contains a critical point. The VDW equation with Fermi statistics is applied to a description of the nuclear matter. The nucleon number fluctuations near the critical point of nuclear matter are studied. The scaled variance, skewness, and kurtosis diverge at the critical point. It is found that the crossover region of the phase diagram is characterized by the large values of the scaled variance, the almost zero skewness, and the significantly negative kurtosis. The rich structures of the skewness and kurtosis are observed in the phase diagram in the wide region around the critical point; namely, they both may attain large positive or negative values.

  12. Elevated Mortality among Birds in Chernobyl as Judged from Skewed Age and Sex Ratios

    PubMed Central

    Møller, Anders Pape; Bonisoli-Alquati, Andrea; Rudolfsen, Geir; Mousseau, Timothy A.

    2012-01-01

    Background Radiation has negative effects on survival of animals including humans, although the generality of this claim is poorly documented under low-dose field conditions. Because females may suffer disproportionately from the effects of radiation on survival due to differences in sex roles during reproduction, radiation-induced mortality may result in male-skewed adult sex ratios. Methodology/Principal Finding We estimated the effects of low-dose radiation on adult survival rates in birds by determining age ratios of adults captured in mist nets during the breeding season in relation to background radiation levels around Chernobyl and in nearby uncontaminated control areas. Age ratios were skewed towards yearlings, especially in the most contaminated areas, implying that adult survival rates were reduced in contaminated areas, and that populations in such areas could only be maintained through immigration from nearby uncontaminated areas. Differential mortality in females resulted in a strongly male-skewed sex ratio in the most contaminated areas. In addition, males sang disproportionately commonly in the most contaminated areas where the sex ratio was male skewed presumably because males had difficulty finding and acquiring mates when females were rare. The results were not caused by permanent emigration by females from the most contaminated areas because none of the recaptured birds had changed breeding site, and the proportion of individuals with morphological abnormalities did not differ significantly between the sexes for areas with normal and higher levels of contamination. Conclusions/Significance These findings are consistent with the hypothesis that the adult survival rate of female birds is particularly susceptible to the effects of low-dose radiation, resulting in male skewed sex ratios at high levels of radiation. Such skewed age ratios towards yearlings in contaminated areas are consistent with the hypothesis that an area exceeding 30,000 km2 in Chernobyl’s surroundings constitutes an ecological trap that causes dramatic excess mortality. PMID:22514722

  13. Cooperativity of complex salt bridges

    PubMed Central

    Gvritishvili, Anzor G.; Gribenko, Alexey V.; Makhatadze, George I.

    2008-01-01

    The energetic contribution of complex salt bridges, in which one charged residue (anchor residue) forms salt bridges with two or more residues simultaneously, has been suggested to have importance for protein stability. Detailed analysis of the net energetics of complex salt bridge formation using double- and triple-mutant cycle analysis revealed conflicting results. In two cases, it was shown that complex salt bridge formation is cooperative, i.e., the net strength of the complex salt bridge is more than the sum of the energies of individual pairs. In one case, it was reported that complex salt bridge formation is anti-cooperative. To resolve these different findings, we performed analysis of the geometries of salt bridges in a representative set of structures from the PDB and found that over 87% of all complex salt bridges anchored by Arg/Lys have a geometry such that the angle formed by their C? atoms, ?, is <90°. This preferred geometry is observed in the two reported instances when the energetics of complex salt bridge formation is cooperative, while in the reported anti-cooperative complex salt bridge, ? is close to 160°. Based on these observations, we hypothesized that complex salt bridges are cooperative for ? < 90° and anti-cooperative for 90° < ? < 180°. To provide a further experimental test for this hypothesis, we engineered a complex salt bridge with ? = 150° into a model protein, the activation domain of human procarboxypeptidase A2 (ADA2h). Experimentally derived stabilities of the ADA2h variants allowed us to show that the complex salt bridge in ADA2h is anti-cooperative. PMID:18469176

  14. Skew-Tolerant Key Distribution for Load Balancing in MapReduce

    NASA Astrophysics Data System (ADS)

    Son, Jihoon; Choi, Hyunsik; Chung, Yon Dohn

    MapReduce is a parallel processing framework for large scale data. In the reduce phase, MapReduce employs the hash scheme in order to distribute data sharing the same key across cluster nodes. However, this approach is not robust for the skewed data distribution. In this paper, we propose a skew-tolerant key distribution method for MapReduce. The proposed method assigns keys to cluster nodes balancing their workloads. We implemented our proposed method on Hadoop. Through experiments, we evaluate the performance of the proposed method in comparison with the conventional method.

  15. Multivariate skew- t approach to the design of accumulation risk scenarios for the flooding hazard

    NASA Astrophysics Data System (ADS)

    Ghizzoni, Tatiana; Roth, Giorgio; Rudari, Roberto

    2010-10-01

    The multivariate version of the skew- t distribution provides a powerful analytical description of the joint behavior of multivariate processes. It enjoys valuable properties: from the aptitude to model skewed as well as leptokurtic datasets to the availability of moments and likelihood analytical expressions. Moreover, it offers a wide range of extremal dependence strength, allowing for upper and lower tail dependence. The idea underneath this work is to employ the multivariate skew- t distribution to provide an estimation of the joint probability of flood events in a multi-site multi-basin approach. This constitutes the basis for the design and evaluation of flood hazard scenarios for large areas in terms of their intensity, extension and frequency, i.e. those information required by civil protection agencies to put in action mitigation strategies and by insurance companies to price the flooding risk and to evaluate portfolios. Performances of the skew- t distribution and the corresponding t copula function, introduced to represent the state of the art for multivariate simulations, are discussed with reference to the Tanaro Basin, North-western Italy. To enhance the characteristics of the correlation structure, three nested and non-nested gauging stations are selected with contributing areas from 1500 to 8000 km 2. A dataset of 76 trivariate flood events is extracted from a mean daily discharges database available for the time period from January 1995 to December 2003. Applications include the generation of multivariate skew- t and t copula samples and models' comparison through the principle of minimum cross-entropy, here revised for the application to multivariate samples. Copula and skew- t based scenario return period estimations are provided for the November 1994 flood event, i.e. the worst on record in the 1801-2001 period. Results are encouraging: the skew- t distribution seems able to describe the joint behavior, being close to the observations. Marginal distributions derived from the skew- t multivariate fit are comparable to the observed ones, and the model is also able to describe the tail behavior.

  16. Robust Inference for State-Space Models with Skewed Measurement Noise

    NASA Astrophysics Data System (ADS)

    Nurminen, Henri; Ardeshiri, Tohid; Piche, Robert; Gustafsson, Fredrik

    2015-11-01

    Filtering and smoothing algorithms for linear discrete-time state-space models with skewed and heavy-tailed measurement noise are presented. The algorithms use a variational Bayes approximation of the posterior distribution of models that have normal prior and skew-t-distributed measurement noise. The proposed filter and smoother are compared with conventional low-complexity alternatives in a simulated pseudorange positioning scenario. In the simulations the proposed methods achieve better accuracy than the alternative methods, the computational complexity of the filter being roughly 5 to 10 times that of the Kalman filter.

  17. High rates of pregnancy loss by subordinates leads to high reproductive skew in wild golden lion tamarins (Leontopithecus rosalia)

    E-print Network

    French, Jeffrey A.

    ÔØ Å ÒÙ× Ö ÔØ High rates of pregnancy loss by subordinates leads to high reproductive skew in wild., French, Jeffrey A., Dietz, James M., High rates of pregnancy loss by subordinates leads to high ACCEPTED MANUSCRIPT TITLE High rates of pregnancy loss by subordinates leads to high reproductive skew

  18. Numerical solution for the velocity-derivative skewness of a low-Reynolds-number decaying Navier-Stokes flow

    NASA Technical Reports Server (NTRS)

    Deissler, Robert G.

    1990-01-01

    The variation of the velocity-derivative skewness of a Navier-Stokes flow as the Reynolds number goes toward zero is calculated numerically. The value of the skewness, which has been somewhat controversial, is shown to become small at low Reynolds numbers.

  19. LEARNINGACTIVITY#4 Design a Truss Bridge

    E-print Network

    Bowen, James D.

    LEARNINGACTIVITY#4 4-1 #4 Design a Truss Bridge with a Computer Learning Activity #4: Overview Point Bridge Designer to design a truss bridge. We will use the software to create a structural model the engineering design process. n Design a truss bridge, using the West Point Bridge Designer software. Key Terms

  20. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE PROCEDURES § 115.40 Bridge repairs. Repairs to a bridge which...

  1. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE PROCEDURES § 115.40 Bridge repairs. Repairs to a bridge which...

  2. Full bridge converter Transformers and isolated converters

    E-print Network

    Knobloch,Jürgen

    Full bridge converter Transformers and isolated converters Most DC power supplies have parts of the B-H curve are used. Include: push-pull, half-bridge, full-bridge (explained below). An example - full-bridge converter Fig. 4: (a) Full-bridge converter. (b) voltage and current waveforms

  3. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE PROCEDURES § 115.40 Bridge repairs. Repairs to a bridge which...

  4. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE PROCEDURES § 115.40 Bridge repairs. Repairs to a bridge which...

  5. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE PROCEDURES § 115.40 Bridge repairs. Repairs to a bridge which...

  6. Bridging biometrics and forensics

    NASA Astrophysics Data System (ADS)

    Yan, Yanjun; Osadciw, Lisa Ann

    2008-02-01

    This paper is a survey on biometrics and forensics, especially on the techniques and applications of face recognition in forensics. This paper describes the differences and connections between biometrics and forensics, and bridges each other by formulating the conditions when biometrics can be applied in forensics. Under these conditions, face recognition, as a non-intrusive and non-contact biometrics, is discussed in detail as an illustration of applying biometrics in forensics. The discussion on face recognition covers different approaches, feature extractions, and decision procedures. The advantages and limitations of biometrics in forensic applications are also addressed.

  7. Nasal Bridge Intramuscular Hemangioma

    PubMed Central

    Hamir Basah, Zulkifli; Ramza Ramli, Ramiza; Gayadh, Maha Khadum; Mutum, Samarendra Singh

    2015-01-01

    Intramuscular haemangioma (IMH) is a benign mesenchymal tumour. It appears as a deep, nontender mass within the soft tissue, particularly in the extremities. This tumour may not be obvious on clinical examination. Head and neck IMHs represent only 13.5% of the total IMHs. The most common site for a head and neck IMH is the masseter muscle, followed by trapezius, sternocleidomastoid, and very rarely temporalis muscle. We present a patient with left nasal bridge swelling which was excised and histologically confirmed as intramuscular hemangioma. PMID:25709848

  8. 5. North side of throughtruss bridge over railroad tracks (bridge ...

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

    5. North side of through-truss bridge over railroad tracks (bridge #U182512605). View to southwest. - South Omaha Union Stock Yards, "O" Street Viaduct, "O" Street Spanning Hog Pens; South Omaha Terminal Railway Company Tracks & Union Pacific Railroad Tracks, Omaha, Douglas County, NE

  9. BridgeSPA: Improving Tor Bridges with Single Packet Authorization

    E-print Network

    Hengartner, Urs

    BridgeSPA: Improving Tor Bridges with Single Packet Authorization Rob Smits rdfsmits@cs.uwaterloo.ca ABSTRACT Tor is a network designed for low-latency anonymous com- munications. Tor clients form circuits these circuits. This indirection makes it difficult for a local adversary to determine with whom a particular Tor

  10. 16. Little Hell Gate Bridge with Big Hell Gate Bridge ...

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

    16. Little Hell Gate Bridge with Big Hell Gate Bridge in background. Wards Island, New York Co., NY. Sec. 4207, MP 8.02. - Northeast Railroad Corridor, Amtrak Route between New Jersey/New York & New York/Connecticut State Lines, New York, New York County, NY

  11. 20. Bronx Kill Bridge with Hell Gate Bridge in background. ...

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

    20. Bronx Kill Bridge with Hell Gate Bridge in background. Randalls Island, New York Co., NY. Sec. 4207, MP 8.54. - Northeast Railroad Corridor, Amtrak Route between New Jersey/New York & New York/Connecticut State Lines, New York, New York County, NY

  12. 25. White Plains Road Bridge in foreground; Unionport Road Bridge ...

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

    25. White Plains Road Bridge in foreground; Unionport Road Bridge in background. Van Nest, Bronx Co., NY. Sec. 4207, MP 12.75./78. - Northeast Railroad Corridor, Amtrak Route between New Jersey/New York & New York/Connecticut State Lines, New York, New York County, NY

  13. Spatial involute gearing -a new type of skew gears Hellmuth Stachel

    E-print Network

    Nawratil, Georg

    of a gear set is usually to transmit a rotary motion of the input wheel 1 about the axis 10p with angularSpatial involute gearing - a new type of skew gears Hellmuth Stachel Institute of Discrete stachel@dmg.tuwien.ac.at Abstract This is a geometric approach to spatial involute gearing which has

  14. Blind separation of skewed signals in instantaneous Nikolaos Mitianoudis, Tania Stathaki

    E-print Network

    Mitianoudis, Nikolaos

    Blind separation of skewed signals in instantaneous mixtures Nikolaos Mitianoudis, Tania Stathaki-- The problem of source separation of instantaneous mixtures has been addressed thoroughly in literature applications, there is a need to identify and separate signals that, apart from being non

  15. On Some Confidence Intervals for Estimating the Mean of a Skewed Population

    ERIC Educational Resources Information Center

    Shi, W.; Kibria, B. M. Golam

    2007-01-01

    A number of methods are available in the literature to measure confidence intervals. Here, confidence intervals for estimating the population mean of a skewed distribution are considered. This note proposes two alternative confidence intervals, namely, Median t and Mad t, which are simple adjustments to the Student's t confidence interval. In…

  16. On the skew-symmetric character of the couple-stress tensor

    E-print Network

    Ali R. Hadjesfandiari

    2015-01-20

    In this paper, the skew-symmetric character of the couple-stress tensor is established as the result of arguments from tensor analysis. Consequently, the couple-stress pseudo-tensor has a true vectorial character. The fundamental step in this development is that the isotropic couple-stress tensor cannot exist.

  17. Using social parasitism to test reproductive skew models in a primitively eusocial wasp.

    PubMed

    Green, Jonathan P; Cant, Michael A; Field, Jeremy

    2014-08-22

    Remarkable variation exists in the distribution of reproduction (skew) among members of cooperatively breeding groups, both within and between species. Reproductive skew theory has provided an important framework for understanding this variation. In the primitively eusocial Hymenoptera, two models have been routinely tested: concessions models, which assume complete control of reproduction by a dominant individual, and tug-of-war models, which assume on-going competition among group members over reproduction. Current data provide little support for either model, but uncertainty about the ability of individuals to detect genetic relatedness and difficulties in identifying traits conferring competitive ability mean that the relative importance of concessions versus tug-of-war remains unresolved. Here, we suggest that the use of social parasitism to generate meaningful variation in key social variables represents a valuable opportunity to explore the mechanisms underpinning reproductive skew within the social Hymenoptera. We present a direct test of concessions and tug-of-war models in the paper wasp Polistes dominulus by exploiting pronounced changes in relatedness and power structures that occur following replacement of the dominant by a congeneric social parasite. Comparisons of skew in parasitized and unparasitized colonies are consistent with a tug-of-war over reproduction within P. dominulus groups, but provide no evidence for reproductive concessions. PMID:24990668

  18. The Curious Anomaly of Skewed Judgment Distributions and Systematic Error in the Wisdom of Crowds

    PubMed Central

    Nash, Ulrik W.

    2014-01-01

    Judgment distributions are often skewed and we know little about why. This paper explains the phenomenon of skewed judgment distributions by introducing the augmented quincunx (AQ) model of sequential and probabilistic cue categorization by neurons of judges. In the process of developing inferences about true values, when neurons categorize cues better than chance, and when the particular true value is extreme compared to what is typical and anchored upon, then populations of judges form skewed judgment distributions with high probability. Moreover, the collective error made by these people can be inferred from how skewed their judgment distributions are, and in what direction they tilt. This implies not just that judgment distributions are shaped by cues, but that judgment distributions are cues themselves for the wisdom of crowds. The AQ model also predicts that judgment variance correlates positively with collective error, thereby challenging what is commonly believed about how diversity and collective intelligence relate. Data from 3053 judgment surveys about US macroeconomic variables obtained from the Federal Reserve Bank of Philadelphia and the Wall Street Journal provide strong support, and implications are discussed with reference to three central ideas on collective intelligence, these being Galton's conjecture on the distribution of judgments, Muth's rational expectations hypothesis, and Page's diversity prediction theorem. PMID:25406078

  19. Generalized Skew Bisubmodularity: A Characterization and a Min-Max Theorem

    E-print Network

    RIMS-1781 Generalized Skew Bisubmodularity: A Characterization and a Min-Max Theorem By Satoru Satoru Fujishige Shin-ichi Tanigawa Yuichi Yoshida May 15, 2013 Abstract Huber, Krokhin, and Powell (Proc polynomial-time algorithms for minimizing submodular functions [12, 13]. Later, Iwata, Fleischer

  20. Generalized Skew Bisubmodularity: A Characterization and a MinMax Theorem

    E-print Network

    RIMS­1781 Generalized Skew Bisubmodularity: A Characterization and a Min­Max Theorem By Satoru Satoru Fujishige # Shin­ichi Tanigawa + Yuichi Yoshida # May 15, 2013 Abstract Huber, Krokhin, and Powell functions [12, 13]. Later, Iwata, Fleischer, and Fujishige [18] and Schrijver [22] independently gave

  1. Exact and simple calculation of mutual impedance for coplanar-skew dipoles

    E-print Network

    Myung, Noh-Hoon

    Exact and simple calculation of mutual impedance for coplanar-skew dipoles J.H. Han and N.H. Myung A novel analysis method to calculate the mutual impedance between two dipoles for a coplanar numerical results. Introduction: Antenna mutual coupling is a significant issue for mobile communication

  2. The curious anomaly of skewed judgment distributions and systematic error in the wisdom of crowds.

    PubMed

    Nash, Ulrik W

    2014-01-01

    Judgment distributions are often skewed and we know little about why. This paper explains the phenomenon of skewed judgment distributions by introducing the augmented quincunx (AQ) model of sequential and probabilistic cue categorization by neurons of judges. In the process of developing inferences about true values, when neurons categorize cues better than chance, and when the particular true value is extreme compared to what is typical and anchored upon, then populations of judges form skewed judgment distributions with high probability. Moreover, the collective error made by these people can be inferred from how skewed their judgment distributions are, and in what direction they tilt. This implies not just that judgment distributions are shaped by cues, but that judgment distributions are cues themselves for the wisdom of crowds. The AQ model also predicts that judgment variance correlates positively with collective error, thereby challenging what is commonly believed about how diversity and collective intelligence relate. Data from 3053 judgment surveys about US macroeconomic variables obtained from the Federal Reserve Bank of Philadelphia and the Wall Street Journal provide strong support, and implications are discussed with reference to three central ideas on collective intelligence, these being Galton's conjecture on the distribution of judgments, Muth's rational expectations hypothesis, and Page's diversity prediction theorem. PMID:25406078

  3. Multivariate skew t mixture models: Applications to fluorescence-activated cell sorting data

    E-print Network

    McLachlan, Geoff

    Multivariate skew t mixture models: Applications to fluorescence-activated cell sorting data Kui of pattern recognition, the data often involve highly asymmetric observations. Normal mixture models tend of the fitted mixture components may be distorted. In this paper, we propose to adopt mixtures of multivariate

  4. A CMOS Delayed Locked Loop (DLL) for Reducing Clock Skew to Under 500ps

    E-print Network

    Ayers, Joseph

    A CMOS Delayed Locked Loop (DLL) for Reducing Clock Skew to Under 500ps Element Phase detector.400 Abstract Thas paper presents a varaable delay lane DLL car- cuat amplemented an a 0.8 p m CMOS technology-pull type clock synchronazataon scheme. The delay lane can be programmed 6 to 18 stages. The DLL carcuat

  5. SLOW SHOCKS AND CONDUCTION FRONTS FROM PETSCHEK RECONNECTION OF SKEWED MAGNETIC FIELDS: TWO-FLUID EFFECTS

    SciTech Connect

    Longcope, D. W.; Bradshaw, S. J.

    2010-08-01

    In models of fast magnetic reconnection, flux transfer occurs within a small portion of a current sheet triggering stored magnetic energy to be thermalized by shocks. When the initial current sheet separates magnetic fields which are not perfectly anti-parallel, i.e., they are skewed, magnetic energy is first converted to bulk kinetic energy and then thermalized in slow magnetosonic shocks. We show that the latter resemble parallel shocks or hydrodynamic shocks for all skew angles except those very near the anti-parallel limit. As for parallel shocks, the structures of reconnection-driven slow shocks are best studied using two-fluid equations in which ions and electrons have independent temperature. Time-dependent solutions of these equations can be used to predict and understand the shocks from reconnection of skewed magnetic fields. The results differ from those found using a single-fluid model such as magnetohydrodynamics. In the two-fluid model, electrons are heated indirectly and thus carry a heat flux always well below the free-streaming limit. The viscous stress of the ions is, however, typically near the fluid-treatable limit. We find that for a wide range of skew angles and small plasma {beta} an electron conduction front extends ahead of the slow shock but remains within the outflow jet. In such cases, conduction will play a more limited role in driving chromospheric evaporation than has been predicted based on single-fluid, anti-parallel models.

  6. Analysis and optimization of VLSI Clock Distribution Networks for skew variability reduction 

    E-print Network

    Rajaram, Anand K.

    2004-11-15

    synthesis.The second part of the thesis deals with optimizing a given clock tree to minimize the unwanted skew variations. Non-tree CDNs have been recognized as a promising approach to overcome the variation problem. We propose a novel non-tree CDN obtained...

  7. Biased Decision-Making: Developing an Understanding of How Positive and Negative Relationships May Skew Judgments

    ERIC Educational Resources Information Center

    Mills, Candice M.; Grant, Meridith G.

    2009-01-01

    The current experiment examines if and when children consider the possibility of relationships skewing judgments when evaluating judgments in different contexts. Eighty-seven 6-year-olds, 8-year-olds, 10-year-olds, and adults heard stories about judges who made decisions matching or mismatching possible relationship biases (e.g. a judge choosing a…

  8. Influence of pressure gradient on streamwise skewness factor in turbulent boundary layer

    NASA Astrophysics Data System (ADS)

    Dró?d?, Artur

    2014-08-01

    The paper shows an effect of favourable and adverse pressure gradients on turbulent boundary layer. The skewness factor of streamwise velocity component was chosen as a measure of the pressure gradient impact. It appears that skewness factor is an indicator of convection velocity of coherent structures, which is not always equal to the average flow velocity. The analysis has been performed based upon velocity profiles measured with hot-wire technique in turbulent boundary layer with pressure gradient corresponding to turbomachinery conditions. The results show that the skewness factor decreases in the flow region subjected to FPG and increases in the APG conditions. The changes of convection velocity and skewness factor are caused by influence of large-scale motion through the mechanism called amplitude modulation. The large-scale motion is less active in FPG and more active in APG, therefore in FPG the production of vortices is random (there are no high and low speed regions), while in the APG the large-scale motion drives the production of vortices. Namely, the vortices appear only in the high-speed regions, therefore have convection velocity higher than local mean velocity. The convection velocity affects directly the turbulent sweep and ejection events. The more flow is dominated by large-scale motion the higher values takes both the convection velocity of small-scale structures and sweep events induced by them.

  9. 11Skewed Distribution of Species Number in Grass Genera: Is It

    E-print Network

    Hilu, Khidir

    165 11Skewed Distribution of Species Number in Grass Genera: Is It a Taxonomic Artefact? K. W. Hilu........................................................................................................................ 165 11.2 The Grass Family (Poaceae .................................................................................................................................... 176 ABSTRACT The grass family (Poaceae) comprises about 10,000 species distributed in some 785 genera

  10. AkashiAkashi--KaikyoKaikyo BridgeBridge CEE 491CEE 491

    E-print Network

    Prevedouros, Panos D.

    6 Lanes ·· Suspension BridgeSuspension Bridge ·· Materials: Steel andMaterials: Steel and ConcreteAkashiAkashi--KaikyoKaikyo BridgeBridge CEE 491CEE 491 Louis SantosLouis Santos TroyTroy SamuraHonshu--Shikoku Bridge AuthorityShikoku Bridge Authority ·· Cost $3.6 billionCost $3.6 billion ·· Toll $20.00Toll $20

  11. 47 CFR 80.1007 - Bridge-to-bridge radiotelephone installation.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Bridge-to-bridge radiotelephone installation. 80.1007 Section 80.1007 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Bridge-to-Bridge Act § 80.1007 Bridge-to-bridge radiotelephone installation. Use of the...

  12. 47 CFR 80.331 - Bridge-to-bridge communication procedure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Bridge-to-bridge communication procedure. 80..., Alarm, Urgency and Safety Procedures § 80.331 Bridge-to-bridge communication procedure. (a) Vessels subject to the Bridge-to-Bridge Act transmitting on the designated navigational frequency must...

  13. 47 CFR 80.163 - Operator requirements of the Bridge-to-Bridge Act.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Operator requirements of the Bridge-to-Bridge... Requirements § 80.163 Operator requirements of the Bridge-to-Bridge Act. Each ship subject to the Bridge-to-Bridge Act must have on board a radio operator who holds a restricted radiotelephone operator permit...

  14. 47 CFR 80.309 - Watch required by the Bridge-to-Bridge Act.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Watch required by the Bridge-to-Bridge Act. 80... Safety Watches § 80.309 Watch required by the Bridge-to-Bridge Act. In addition to the watch requirement contained in § 80.148, all vessels subject to the Bridge-to-Bridge Act must keep a watch on the...

  15. 47 CFR 80.1007 - Bridge-to-bridge radiotelephone installation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Bridge-to-bridge radiotelephone installation. 80.1007 Section 80.1007 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Bridge-to-Bridge Act § 80.1007 Bridge-to-bridge radiotelephone installation. Use of the...

  16. 47 CFR 80.1007 - Bridge-to-bridge radiotelephone installation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Bridge-to-bridge radiotelephone installation. 80.1007 Section 80.1007 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Bridge-to-Bridge Act § 80.1007 Bridge-to-bridge radiotelephone installation. Use of the...

  17. 47 CFR 80.309 - Watch required by the Bridge-to-Bridge Act.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Watch required by the Bridge-to-Bridge Act. 80... Safety Watches § 80.309 Watch required by the Bridge-to-Bridge Act. In addition to the watch requirement contained in § 80.148, all vessels subject to the Bridge-to-Bridge Act must keep a watch on the...

  18. 47 CFR 80.331 - Bridge-to-bridge communication procedure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Bridge-to-bridge communication procedure. 80..., Alarm, Urgency and Safety Procedures § 80.331 Bridge-to-bridge communication procedure. (a) Vessels subject to the Bridge-to-Bridge Act transmitting on the designated navigational frequency must...

  19. 47 CFR 80.1007 - Bridge-to-bridge radiotelephone installation.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Bridge-to-bridge radiotelephone installation. 80.1007 Section 80.1007 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Bridge-to-Bridge Act § 80.1007 Bridge-to-bridge radiotelephone installation. Use of the...

  20. 47 CFR 80.309 - Watch required by the Bridge-to-Bridge Act.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Watch required by the Bridge-to-Bridge Act. 80... Safety Watches § 80.309 Watch required by the Bridge-to-Bridge Act. In addition to the watch requirement contained in § 80.148, all vessels subject to the Bridge-to-Bridge Act must keep a watch on the...

  1. 47 CFR 80.331 - Bridge-to-bridge communication procedure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Bridge-to-bridge communication procedure. 80..., Alarm, Urgency and Safety Procedures § 80.331 Bridge-to-bridge communication procedure. (a) Vessels subject to the Bridge-to-Bridge Act transmitting on the designated navigational frequency must...

  2. 47 CFR 80.163 - Operator requirements of the Bridge-to-Bridge Act.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Operator requirements of the Bridge-to-Bridge... Requirements § 80.163 Operator requirements of the Bridge-to-Bridge Act. Each ship subject to the Bridge-to-Bridge Act must have on board a radio operator who holds a restricted radiotelephone operator permit...

  3. 47 CFR 80.163 - Operator requirements of the Bridge-to-Bridge Act.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Operator requirements of the Bridge-to-Bridge... Requirements § 80.163 Operator requirements of the Bridge-to-Bridge Act. Each ship subject to the Bridge-to-Bridge Act must have on board a radio operator who holds a restricted radiotelephone operator permit...

  4. 47 CFR 80.309 - Watch required by the Bridge-to-Bridge Act.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Watch required by the Bridge-to-Bridge Act. 80... Safety Watches § 80.309 Watch required by the Bridge-to-Bridge Act. In addition to the watch requirement contained in § 80.148, all vessels subject to the Bridge-to-Bridge Act must keep a watch on the...

  5. 47 CFR 80.331 - Bridge-to-bridge communication procedure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Bridge-to-bridge communication procedure. 80..., Alarm, Urgency and Safety Procedures § 80.331 Bridge-to-bridge communication procedure. (a) Vessels subject to the Bridge-to-Bridge Act transmitting on the designated navigational frequency must...

  6. 47 CFR 80.309 - Watch required by the Bridge-to-Bridge Act.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Watch required by the Bridge-to-Bridge Act. 80... Safety Watches § 80.309 Watch required by the Bridge-to-Bridge Act. In addition to the watch requirement contained in § 80.148, all vessels subject to the Bridge-to-Bridge Act must keep a watch on the...

  7. 47 CFR 80.331 - Bridge-to-bridge communication procedure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Bridge-to-bridge communication procedure. 80..., Alarm, Urgency and Safety Procedures § 80.331 Bridge-to-bridge communication procedure. (a) Vessels subject to the Bridge-to-Bridge Act transmitting on the designated navigational frequency must...

  8. 47 CFR 80.163 - Operator requirements of the Bridge-to-Bridge Act.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Operator requirements of the Bridge-to-Bridge... Requirements § 80.163 Operator requirements of the Bridge-to-Bridge Act. Each ship subject to the Bridge-to-Bridge Act must have on board a radio operator who holds a restricted radiotelephone operator permit...

  9. 47 CFR 80.1007 - Bridge-to-bridge radiotelephone installation.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Bridge-to-bridge radiotelephone installation. 80.1007 Section 80.1007 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND... Bridge-to-Bridge Act § 80.1007 Bridge-to-bridge radiotelephone installation. Use of the...

  10. 47 CFR 80.163 - Operator requirements of the Bridge-to-Bridge Act.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Operator requirements of the Bridge-to-Bridge... Requirements § 80.163 Operator requirements of the Bridge-to-Bridge Act. Each ship subject to the Bridge-to-Bridge Act must have on board a radio operator who holds a restricted radiotelephone operator permit...

  11. Effects of Trophic Skewing of Species Richness on Ecosystem Functioning in a Diverse Marine Community

    PubMed Central

    Reynolds, Pamela L.; Bruno, John F.

    2012-01-01

    Widespread overharvesting of top consumers of the world’s ecosystems has “skewed” food webs, in terms of biomass and species richness, towards a generally greater domination at lower trophic levels. This skewing is exacerbated in locations where exotic species are predominantly low-trophic level consumers such as benthic macrophytes, detritivores, and filter feeders. However, in some systems where numerous exotic predators have been added, sometimes purposefully as in many freshwater systems, food webs are skewed in the opposite direction toward consumer dominance. Little is known about how such modifications to food web topology, e.g., changes in the ratio of predator to prey species richness, affect ecosystem functioning. We experimentally measured the effects of trophic skew on production in an estuarine food web by manipulating ratios of species richness across three trophic levels in experimental mesocosms. After 24 days, increasing macroalgal richness promoted both plant biomass and grazer abundance, although the positive effect on plant biomass disappeared in the presence of grazers. The strongest trophic cascade on the experimentally stocked macroalgae emerged in communities with a greater ratio of prey to predator richness (bottom-rich food webs), while stronger cascades on the accumulation of naturally colonizing algae (primarily microalgae with some early successional macroalgae that recruited and grew in the mesocosms) generally emerged in communities with greater predator to prey richness (the more top-rich food webs). These results suggest that trophic skewing of species richness and overall changes in food web topology can influence marine community structure and food web dynamics in complex ways, emphasizing the need for multitrophic approaches to understand the consequences of marine extinctions and invasions. PMID:22693549

  12. Designing and Building File-Folder Bridges

    E-print Network

    Bowen, James D.

    .....................................................................................v Learning Activity #1: Build a Model of a Truss Bridge ............................................................3-1 Learning Activity #4: Design a Truss Bridge with a Computer.........................................4-1 Learning Activity #5: Design and Build a Model Truss Bridge

  13. Development of a bridge fault extractor tool 

    E-print Network

    Bhat, Nandan D.

    2005-02-17

    Bridge fault extractors are tools that analyze chip layouts and produce a realistic list of bridging faults within that chip. FedEx, previously developed at Texas A&M University, extracts all two-node intralayer bridges ...

  14. Bridging properties of multiblock copolymers.

    SciTech Connect

    Rasmussen, K. O.; Kober, E. M.; Lookman, T.; Saxena, A. B.

    2003-01-01

    Using self-consistent field theory, we attempt to elucidate the links between microscopically determined properties, such as the bridging fraction of chains, and mechanical properties of multiblock copolymer materials. We determine morphological aspects such as period and interfacial width and calculate the bridging fractions, and compare with experimental data .

  15. Mathematics in Use: Suspension Bridges.

    ERIC Educational Resources Information Center

    Ginther, John L.

    1992-01-01

    Reviews the mathematics utilized in the design and construction of suspension bridges, in general, then illustrates these mathematical concepts by examining data associated with the Mackinac Bridge, which connects the two peninsulas of Michigan. Emphasizes the strong interest factor these gigantic structures have for students by attaching a sense…

  16. Burning trees and bridges

    NASA Technical Reports Server (NTRS)

    Levine, Joel S.

    1990-01-01

    Most burning of biomass is the result of human activity, and on a global scale it is increasing. Tropospheric concentrations of CO2, CO, CH4, non-methane hydrocarbons, and ozone are all increasing with time; global biomass burning may make an important contribution to this increase and thus to potential global climate change. The nitrogen cycle also can have important climatic effects. Nitrous oxide put into the atmosphere by biomass burning is a greenhouse gas 250 times more powerful (molecule for molecule) than carbon dioxide. Nitric oxide, as well as being a photochemical precursor of ozone, a major pollutant in the troposphere, produces nitric acid, the fastest-growing component of acid rain. Hence, the new bridge in the nitrogen cycle is of more than mere technical interest.

  17. A bridge between cultures

    NASA Astrophysics Data System (ADS)

    Friebele, Elaine

    Journalists who report on scientific discoveries and the scientists who make them are, in many cases, separated by a Grand Canyon-sized gap. A recent U.S. survey revealed that journalists believe that scientists' jargon prevents effective communication. Scientists polled in the same survey, conducted by Today Show host Jim Hartz and NASA scientist Rick Chappell, said that journalists need to do a better job of verifying facts and interpreting scientific results.Panelists representing the scientific and media communities will discuss ways to bridge that gap during the “Science and the Media” episode of Freedom Speaks, to be aired by Public Broadcasting Stations in May and June (check your local listings).

  18. Cascaded resonant bridge converters

    NASA Technical Reports Server (NTRS)

    Stuart, Thomas A. (Inventor)

    1989-01-01

    A converter for converting a low voltage direct current power source to a higher voltage, high frequency alternating current output for use in an electrical system where it is desired to use low weight cables and other circuit elements. The converter has a first stage series resonant (Schwarz) converter which converts the direct current power source to an alternating current by means of switching elements that are operated by a variable frequency voltage regulator, a transformer to step up the voltage of the alternating current, and a rectifier bridge to convert the alternating current to a direct current first stage output. The converter further has a second stage series resonant (Schwarz) converter which is connected in series to the first stage converter to receive its direct current output and convert it to a second stage high frequency alternating current output by means of switching elements that are operated by a fixed frequency oscillator. The voltage of the second stage output is controlled at a relatively constant value by controlling the first stage output voltage, which is accomplished by controlling the frequency of the first stage variable frequency voltage controller in response to second stage voltage. Fault tolerance in the event of a load short circuit is provided by making the operation of the first stage variable frequency voltage controller responsive to first and second stage current limiting devices. The second stage output is connected to a rectifier bridge whose output is connected to the input of the second stage to provide good regulation of output voltage wave form at low system loads.

  19. TsingTsing Ma BridgeMa Bridge University of Hawaii at ManoaUniversity of Hawaii at Manoa

    E-print Network

    Prevedouros, Panos D.

    --First long span suspension bridge in typhoon zoneFirst long span suspension bridge in typhoon zoneTsingTsing Ma BridgeMa Bridge University of Hawaii at ManoaUniversity of Hawaii at Manoa CEE 491CEE as a motorway bridge, freeway bridgeUsed as a motorway bridge, freeway bridge and a railway bridgeand a railway

  20. Optimization Of Mean-Semivariance-Skewness Portfolio Selection Model In Fuzzy Random Environment

    NASA Astrophysics Data System (ADS)

    Chatterjee, Amitava; Bhattacharyya, Rupak; Mukherjee, Supratim; Kar, Samarjit

    2010-10-01

    The purpose of the paper is to construct a mean-semivariance-skewness portfolio selection model in fuzzy random environment. The objective is to maximize the skewness with predefined maximum risk tolerance and minimum expected return. Here the security returns in the objectives and constraints are assumed to be fuzzy random variables in nature and then the vagueness of the fuzzy random variables in the objectives and constraints are transformed into fuzzy variables which are similar to trapezoidal numbers. The newly formed fuzzy model is then converted into a deterministic optimization model. The feasibility and effectiveness of the proposed method is verified by numerical example extracted from Bombay Stock Exchange (BSE). The exact parameters of fuzzy membership function and probability density function are obtained through fuzzy random simulating the past dates.

  1. Skew-Quad Parametric-Resonance Ionization Cooling: Theory and Modeling

    SciTech Connect

    Afanaciev, Andre; Derbenev, Yaroslav S.; Morozov, Vasiliy; Sy, Amy; Johnson, Rolland P.

    2015-09-01

    Muon beam ionization cooling is a key component for the next generation of high-luminosity muon colliders. To reach adequately high luminosity without excessively large muon intensities, it was proposed previously to combine ionization cooling with techniques using a parametric resonance (PIC). Practical implementation of PIC proposal is a subject of this report. We show that an addition of skew quadrupoles to a planar PIC channel gives enough flexibility in the design to avoid unwanted resonances, while meeting the requirements of radially-periodic beam focusing at ionization-cooling plates, large dynamic aperture and an oscillating dispersion needed for aberration corrections. Theoretical arguments are corroborated with models and a detailed numerical analysis, providing step-by-step guidance for the design of Skew-quad PIC (SPIC) beamline.

  2. Muon Tracking Studies in a Skew Parametric Resonance Ionization Cooling Channel

    SciTech Connect

    Sy, Amy; Afanaciev, Andre; Derbenev, Yaroslav S.; Johnson, Rolland; Morozov, Vasiliy

    2015-09-01

    Skew Parametric-resonance Ionization Cooling (SPIC) is an extension of the Parametric-resonance Ionization Cooling (PIC) framework that has previously been explored as the final 6D cooling stage of a high-luminosity muon collider. The addition of skew quadrupoles to the PIC magnetic focusing channel induces coupled dynamic behavior of the beam that is radially periodic. The periodicity of the radial motion allows for the avoidance of unwanted resonances in the horizontal and vertical transverse planes, while still providing periodic locations at which ionization cooling components can be implemented. A first practical implementation of the magnetic field components required in the SPIC channel is modeled in MADX. Dynamic features of the coupled correlated optics with and without induced parametric resonance are presented and discussed.

  3. Olfactory learning skews mushroom body output pathways to steer behavioral choice in Drosophila.

    PubMed

    Owald, David; Waddell, Scott

    2015-12-01

    Learning permits animals to attach meaning and context to sensory stimuli. How this information is coded in neural networks in the brain, and appropriately retrieved and utilized to guide behavior, is poorly understood. In the fruit fly olfactory memories of particular value are represented within sparse populations of odor-activated Kenyon cells (KCs) in the mushroom body ensemble. During learning reinforcing dopaminergic neurons skew the mushroom body network by driving zonally restricted plasticity at synaptic junctions between the KCs and subsets of the overall small collection of mushroom body output neurons. Reactivation of this skewed KC-output neuron network retrieves memory of odor valence and guides appropriate approach or avoidance behavior. PMID:26496148

  4. Geometrically nonlinear static and dynamic analysis of functionally graded skew plates

    NASA Astrophysics Data System (ADS)

    Upadhyay, A. K.; Shukla, K. K.

    2013-08-01

    The present paper deals with nonlinear static and dynamic behavior of functionally graded skew plates. The equations of motion are derived using higher order shear deformation theory in conjunction with von-Karman's nonlinear kinematics. The physical domain is mapped into computational domain using linear mapping and chain rule of differentiation. The spatial and temporal discretization is based on fast converging finite double Chebyshev series and Houbolt's method. Quadratic extrapolation technique is employed to linearize the governing nonlinear equations. The spatial and temporal convergence and validation studies have been carried out to establish the efficacy of the present solution methodology. In case of dynamic analysis, the results are obtained for uniform step, sine, half sine, triangular and exponential type of loadings. The effect of volume fraction index, skew angle and boundary conditions on nonlinear displacement and moment response are presented.

  5. Skew Projection of Echo-Detected EPR Spectra for Increased Sensitivity and Resolution

    PubMed Central

    Bowman, Michael K.; Krzyaniak, Matthew D.; Cruce, Alex A.; Weber, Ralph T.

    2013-01-01

    The measurement of EPR spectra during pulsed EPR experiments is commonly accomplished by recording the integral of the electron spin echo as the applied magnetic field is stepped through the spectrum. This approach to echo-detected EPR spectral measurement (ED-EPR) limits sensitivity and spectral resolution and can cause gross distortions in the resulting spectra because some of the information present in the electron spin echo is discarded in such measurements. However, Fourier Transformation of echo shapes measured at a series of magnetic field values followed by skew projection onto either a magnetic field or resonance frequency axis can increase both spectral resolution and sensitivity without the need to trade one against the other. Examples of skew-projected spectra with single crystals, glasses and powders show resolution improvements as large as a factor of seven with sensitivity increases of as much as a factor of five. PMID:23644351

  6. Skewness and Kurtosis as Indicators of Non-Gaussianity in Sky Maps

    E-print Network

    Ben-David, Assaf; Jackson, Andrew D

    2015-01-01

    Observational cosmology is entering an era in which high precision will be required in both measurement and data analysis. Accuracy, however, can only be achieved with a thorough understanding of potential sources of contamination from foreground effects. Our primary focus will be on non- Gaussian effects in foregrounds. This issue will be crucial for coming experiments to determine B-mode polarization. We propose a novel method for investigating a data set in terms of skewness and kurtosis in locally defined regions that collectively cover the entire sky. The method is demonstrated on two sky maps: (i) the SMICA map of Cosmic Microwave Background fluctuations provided by the Planck Collaboration and (ii) a version of the Haslam map at 408 MHz that describes synchrotron radiation. We find that skewness and kurtosis can be evaluated in combination to reveal local physical information. In the present case, we demonstrate that the local properties of both maps are predominantly Gaussian. This result was expected...

  7. Commutative n-ary superalgebras with an invariant skew-symmetric form

    NASA Astrophysics Data System (ADS)

    Vishnyakova, E. G.

    2015-12-01

    We study n-ary commutative superalgebras and L?-algebras that possess a skew-symmetric invariant form, using the derived bracket formalism. This class of superalgebras includes for instance Lie algebras and their n-ary generalizations, commutative associative and Jordan algebras with an invariant form. We give a classification of anti-commutative m-dimensional (m - 3) -ary algebras with an invariant form, and a classification of real simple m-dimensional Lie (m - 3) -algebras with a positive definite invariant form up to isometry. Furthermore, we develop the Hodge Theory for L?-algebras with a symmetric invariant form, and we describe quasi-Frobenius structures on skew-symmetric n-ary algebras.

  8. Skew ray tracing in a step-index optical fiber using Geometric Algebra

    E-print Network

    Ang, Angeleene; McNamara, Daniel J

    2015-01-01

    We used Geometric Algebra to compute the paths of skew rays in a cylindrical, step-index multimode optical fiber. To do this, we used the vector addition form for the law of propagation, the exponential of an imaginary vector form for the law of refraction, and the juxtaposed vector product form for the law of reflection. In particular, the exponential forms of the vector rotations enables us to take advantage of the addition or subtraction of exponential arguments of two rotated vectors in the derivation of the ray tracing invariants in cylindrical and spherical coordinates. We showed that the light rays inside the optical fiber trace a polygonal helical path characterized by three invariants that relate successive reflections inside the fiber: the ray path distance, the difference in axial distances, and the difference in the azimuthal angles. We also rederived the known generalized formula for the numerical aperture for skew rays, which simplifies to the standard form for meridional rays.

  9. Spin Hall effect induced by Bi impurities in Cu: Skew scattering and side-jump

    NASA Astrophysics Data System (ADS)

    Levy, Peter M.; Yang, Hongxin; Chshiev, Mairbek; Fert, Albert

    2013-12-01

    The spin Hall effect (SHE) has recently turned out to be an interesting tool for the conversion between charge and spin currents, the conversion factor being characterized by the spin Hall angle ?H. Large spin Hall angles have been now measured in heavy metals like W (?H=-0.33) and Cu doped with Bi impurities (?H=-0.24). In this article we express the contributions to the SHE induced by skew scattering and scattering with side-jump from Bi impurities in Cu, and we use ab initio calculations of the electronic structure of CuBi alloys to estimate the values of these two contributions. The predominant effect comes from skew scattering; the spin Hall angle is negative in agreement with experiments, but the calculated amplitude is smaller.

  10. Surveying and optical tooling technologies combined to align a skewed beamline at the LAMPF accelerator

    SciTech Connect

    Bauke, W.; Clark, D.A.; Trujillo, P.B.

    1985-01-01

    Optical Tooling evolved from traditional surveying, and both technologies are sometimes used interchangeably in large industrial installations, since the instruments and their specialized adapters and supports complement each other well. A unique marriage of both technologies was accomplished in a novel application at LAMPF, the Los Alamos Meson Physics Facility. LAMPF consists of a linear accelerator with multiple target systems, one of which had to be altered to accommodate a new beamline for a neutrino experiment. The new line was to be installed into a crowded beam tunnel and had to be skewed and tilted in compound angles to avoid existing equipment. In this paper we describe how Optical Tooling was used in conjunction with simple alignment and reference fixtures to set fiducials on the magnets and other mechanical components of the beamline, and how theodolites and sight levels were then adapted to align these components along the calculated skew planes. Design tolerances are compared with measured alignment results.

  11. Post-earthquake Prioritization of Bridge Inspections

    E-print Network

    Eberhard, Marc O.

    .3 s. Bridges constructed before the 1940s, movable bridges, and older trusses were particularly and older trusses as "other" bridges. An inspection prioritization strategy was developed that combinesPost-earthquake Prioritization of Bridge Inspections R. T. Ranf,a... M.EERI, M. O. Eberhard,b... M

  12. Washed Out Bridge, Snake Creek Near Whitesburg

    USGS Multimedia Gallery

    Tributary to Snake Creek, near Whitesburg, Georgia, showing a washed out bridge. When bridges such as this one collapse during a flood, it is rarely the pressure of the rushing water against the bridge that causes the bridge to fail. Rather, the rushing water erodes the ground underneath and surroun...

  13. Balsa Wood Bridge Competition Sponsored by

    E-print Network

    Wang, Xiaorui "Ray"

    Balsa Wood Bridge Competition Sponsored by: The University of Tennessee, Department of Civil bridge capable of supporting a given load over a given span. The bridge must allow the passage of one Hot Wheel's Car of any variety along the entire length. EACH SCHOOL MAY BRING 1 BRIDGE!!! Materials

  14. atom cell body bridge.usc.edu

    E-print Network

    Zhou, Xianghong Jasmine

    atom ­ cell ­ body bridge.usc.edu Bridge UnderGraduate Science Program Kicks Off! Aug. 15, 2015 ­ If you're wondering what the buzz is about, it's the inaugural Bridge UnderGraduate Science (or, BUGS in custom, individualized research projects in our laboratories as part of The Bridge@USC initiative. We

  15. 77 FR 16784 - General Bridge Regulation; Amendment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-22

    ... SECURITY Coast Guard 33 CFR Part 114, 116, 118 RIN 1625-AB36 General Bridge Regulation; Amendment AGENCY... rulemaking concerning amendments to the general bridge regulations. The rulemaking was initiated to clarify the statutory responsibilities of bridge owners to remove their bridges from navigable waterways...

  16. Quantum integrable systems, non-skew-symmetric r-matrices and algebraic Bethe ansatz

    SciTech Connect

    Skrypnyk, T.

    2007-02-15

    We prove the integrability of the general quantum Hamiltonian systems governed by an arbitrary non-skew-symmetric, so(3)-valued, nondynamical classical r-matrix with spectral parameters. We consider the most interesting example of these quantum integrable systems, namely, the so(3) 'generalized Gaudin systems' in detail. In the case of an arbitrary r-matrix which is 'diagonal' in the sl(2) basis we calculate the spectrum and the eigenvalues of the corresponding Hamiltonians using the algebraic Bethe ansatz technique.

  17. Physical structures. Forming physical fields and manifolds. (Properties of skew-symmetric differential forms)

    E-print Network

    L. I. Petrova

    2004-04-20

    It is shown that physical fields are formed by physical structures, which in their properties are differential-geometrical structures. These results have been obtained due to using the mathematical apparatus of skew-symmetric differential forms. This apparatus discloses the controlling role of the conservation laws in evolutionary processes, which proceed in material media and lead to origination of physical structures and forming physical fields and manifolds.

  18. Permanent Magnet Skew Quadrupoles for the Low Emittance LER Lattice of PEP-II

    SciTech Connect

    Decker, F.-J.; Anderson, S.; Kharakh, D.; Sullivan, M.; /SLAC

    2011-07-05

    The vertical emittance of the low energy ring (LER) in the PEP-II B-Factory was reduced by using skew quadrupoles consisting of permanent magnet material. The advantages over electric quadrupoles or rotating existing normal quadrupoles are discussed. To assure a high field quality, a Biot-Savart calculation was used to cancel the natural 12-pole component by using different size poles over a few layers. A magnetic measurement confirmed the high quality of the magnets. After installation and adjusting the original electric 12 skew and 16 normal quadrupoles the emittance contribution from the region close to the interaction point, which was the biggest part in the original design, was considerably reduced. To strengthen the vertical behavior of the LER beam, a low emittance lattice was developed. It lowered the original vertical design emittance from 0.54 nm-rad to 0.034 nm-rad. In order to achieve this, additional skew quadrupoles were required to bring the coupling correction out of the arcs and closer to the detector solenoid in the straight (Fig. 1). It is important, together with low vertical dispersion, that the low vertical emittance is not coupled into the horizontal, which is what we get if the coupling correction continues into the arcs. Further details of the lattice work is described in another paper; here we concentrate on the development of the permanent skew (PSK) quadrupole solution. Besides the permanent magnets there are two other possibilities, using electric magnets or rotating normal quadrupoles. Electric magnets would have required much more additional equipment like magnets stands, power supply, and new vacuum chamber sections. Rotating existing quadrupoles was also not feasible since they are mostly mounted together with a bending magnet on the same support girder.

  19. Measuring skewness of red blood cell deformability distribution by laser ektacytometry

    SciTech Connect

    Nikitin, S Yu; Priezzhev, A V; Lugovtsov, A E; Ustinov, V D

    2014-08-31

    An algorithm is proposed for measuring the parameters of red blood cell deformability distribution based on laser diffractometry of red blood cells in shear flow (ektacytometry). The algorithm is tested on specially prepared samples of rat blood. In these experiments we succeeded in measuring the mean deformability, deformability variance and skewness of red blood cell deformability distribution with errors of 10%, 15% and 35%, respectively. (laser biophotonics)

  20. The role of the SST-thermocline relationship in Indian Ocean Dipole skewness and its response to global warming.

    PubMed

    Ng, Benjamin; Cai, Wenju; Walsh, Kevin

    2014-01-01

    A positive Indian Ocean Dipole (IOD) tends to have stronger cold sea surface temperature anomalies (SSTAs) over the eastern Indian Ocean with greater impacts than warm SSTAs that occur during its negative phase. Two feedbacks have been suggested as the cause of positive IOD skewness, a positive Bjerknes feedback and a negative SST-cloud-radiation (SCR) feedback, but their relative importance is debated. Using inter-model statistics, we show that the most important process for IOD skewness is an asymmetry in the thermocline feedback, whereby SSTAs respond to thermocline depth anomalies more strongly during the positive phase than negative phase. This asymmetric thermocline feedback drives IOD skewness despite positive IODs receiving greater damping from the SCR feedback. In response to global warming, although the thermocline feedback strengthens, its asymmetry between positive and negative IODs weakens. This behaviour change explains the reduction in IOD skewness that many models display under global warming. PMID:25112717

  1. The role of the SST-thermocline relationship in Indian Ocean Dipole skewness and its response to global warming

    PubMed Central

    Ng, Benjamin; Cai, Wenju; Walsh, Kevin

    2014-01-01

    A positive Indian Ocean Dipole (IOD) tends to have stronger cold sea surface temperature anomalies (SSTAs) over the eastern Indian Ocean with greater impacts than warm SSTAs that occur during its negative phase. Two feedbacks have been suggested as the cause of positive IOD skewness, a positive Bjerknes feedback and a negative SST-cloud-radiation (SCR) feedback, but their relative importance is debated. Using inter-model statistics, we show that the most important process for IOD skewness is an asymmetry in the thermocline feedback, whereby SSTAs respond to thermocline depth anomalies more strongly during the positive phase than negative phase. This asymmetric thermocline feedback drives IOD skewness despite positive IODs receiving greater damping from the SCR feedback. In response to global warming, although the thermocline feedback strengthens, its asymmetry between positive and negative IODs weakens. This behaviour change explains the reduction in IOD skewness that many models display under global warming. PMID:25112717

  2. Mineral bridges in nacre revisited

    E-print Network

    Antonio G. Checa; Julyan H. E. Cartwright; Marc-Georg Willinger

    2012-07-20

    We confirm with high-resolution techniques the existence of mineral bridges between superposed nacre tablets. In the towered nacre of both gastropods and the cephalopod Nautilus there are large bridges aligned along the tower axes, corresponding to gaps (150-200 nm) in the interlamellar membranes. Gaps are produced by the interaction of the nascent tablets with a surface membrane that covers the nacre compartment. In the terraced nacre of bivalves bridges associated with elongated gaps in the interlamellar membrane (> 100 nm) have mainly been found at or close to the edges of superposed parental tablets. To explain this placement, we hypothesize that the interlamellar membrane breaks due to differences in osmotic pressure across it when the interlamellar space below becomes reduced at an advanced stage of calcification. In no cases are the minor connections between superimposed tablets (mineral bridges, found to be such.

  3. Joint Skewness and Its Application in Unsupervised Band Selection for Small Target Detection

    PubMed Central

    Geng, Xiurui; Sun, Kang; Ji, Luyan; Tang, Hairong; Zhao, Yongchao

    2015-01-01

    Few band selection methods are specially designed for small target detection. It is well known that the information of small targets is most likely contained in non-Gaussian bands, where small targets are more easily separated from the background. On the other hand, correlation of band set also plays an important role in the small target detection. When the selected bands are highly correlated, it will be unbeneficial for the subsequent detection. However, the existing non-Gaussianity-based band selection methods have not taken the correlation of bands into account, which generally result in high correlation of obtained bands. In this paper, combining the third-order (third-order tensor) and second-order (correlation) statistics of bands, we define a new concept, named joint skewness, for multivariate data. Moreover, we also propose an easy-to-implement approach to estimate this index based on high-order singular value decomposition (HOSVD). Based on the definition of joint skewness, we present an unsupervised band selection for small target detection for hyperspectral data, named joint skewness band selection (JSBS). The evaluation results demonstrate that the bands selected by JSBS are very effective in terms of small target detection. PMID:25873018

  4. Squaring the Circle: Geometric Skewness and Symmetry Breaking for Passive Scalar Transport in Ducts and Pipes

    NASA Astrophysics Data System (ADS)

    Aminian, Manuchehr; Bernardi, Francesca; Camassa, Roberto; McLaughlin, Richard M.

    2015-10-01

    We study the role geometry plays in the emergence of asymmetries in diffusing passive scalars advected by pressure-driven flows in ducts and pipes of different aspect ratios. We uncover nonintuitive, multi-time-scale behavior gauged by a new statistic, which we term "geometric skewness" SG, which measures instantaneously forming asymmetries at short times due to flow geometry. This signature distinguishes elliptical pipes of any aspect ratio, for which SG=0 , from rectangular ducts whose SG is generically nonzero, and, interestingly, shows that a special duct of aspect ratio ?0.533 35 behaves like a circular pipe as its geometric skewness vanishes. Using a combination of exact solutions, novel short-time asymptotics, and Monte Carlo simulations, we establish the relevant time scales for plateaus and extrema in the evolution of the skewness and kurtosis for our class of geometries. For ducts limiting to channel geometries, we present new exact, single-series formulas for the first four moments on slices used to benchmark Monte Carlo simulations.

  5. A Bayesian estimate of the concordance correlation coefficient with skewed data.

    PubMed

    Feng, Dai; Baumgartner, Richard; Svetnik, Vladimir

    2015-01-01

    Concordance correlation coefficient (CCC) is one of the most popular scaled indices used to evaluate agreement. Most commonly, it is used under the assumption that data is normally distributed. This assumption, however, does not apply to skewed data sets. While methods for the estimation of the CCC of skewed data sets have been introduced and studied, the Bayesian approach and its comparison with the previous methods has been lacking. In this study, we propose a Bayesian method for the estimation of the CCC of skewed data sets and compare it with the best method previously investigated. The proposed method has certain advantages. It tends to outperform the best method studied before when the variation of the data is mainly from the random subject effect instead of error. Furthermore, it allows for greater flexibility in application by enabling incorporation of missing data, confounding covariates, and replications, which was not considered previously. The superiority of this new approach is demonstrated using simulation as well as real-life biomarker data sets used in an electroencephalography clinical study. The implementation of the Bayesian method is accessible through the Comprehensive R Archive Network. PMID:26033433

  6. WORLD WISE'99-Winnipeg, Manitoba Taylor Bridge -A Bridge For the 21st

    E-print Network

    WORLD WISE'99- Winnipeg, Manitoba Taylor Bridge - A Bridge For the 21st Century Taylor Bridge - A Bridge For the 21st Century Emile ShehataI, Rick Haldane-Wilsone1 , Doug Stewart!, Gamil Tadros2 and Sami and build the Taylor "smart" Bridge utilizing fibre reinforced polymer (FRP) reinforcing materials

  7. Bridge Funding Bridge funding is designed to stabilize meritorious research programs that have lost extramural

    E-print Network

    Brownstone, Rob

    Bridge Funding Overview: Bridge funding is designed to stabilize meritorious research programs that have lost extramural funding. Bridge funds are for one year and are intended to enhance the likelihood by the applicant's Department/Division. Applicants may only request bridge funding once per calendar year. Bridge

  8. GAUVREAU, The Three Myths of Bridge Aesthetics, 1/8 THE THREE MYTHS OF BRIDGE AESTHETICS

    E-print Network

    Gauvreau, Paul

    wisdom on bridge aesthetics. If bridge design is to be recognized as a valid and distinct means of the flow of forces are irrelevant). The works of Maillart, Roebling, and other masters of bridge design of artistic significance. 1. Introduction: Creating Bridges as Art If bridge design is a valid means

  9. The Higgs Bridge

    E-print Network

    Roland E. Allen

    2013-12-01

    The particle recently discovered at the Large Hadron Collider near Geneva is almost certainly a Higgs boson, the long-sought completion of the Standard Model of particle physics. But this discovery, an achievement by more than six thousand scientists (including students), is actually much more than a mere capstone of the Standard Model. It instead represents a bridge from the Standard Model to exciting discoveries of the future, at higher energies or in other experiments, and to the properties of matter at very low temperatures. The mere existence of a particle with zero spin implies a need for new physics, with the most likely candidate being supersymmetry, which requires that every known particle has a superpartner yet to be discovered. And phenomena similar to the Higgs are seen in superconducting metals and superfluid gases at low temperatures, which extend down to a millionth or even a billionth of a degree Kelvin. So the discovery of a Higgs boson has a central place in our attempts both to achieve a true understanding of Nature and to harness Nature in practical applications.

  10. Earthquake Response of Suspension Bridges

    NASA Astrophysics Data System (ADS)

    Erdik, Mustafa; Apayd?n, Nurdan

    Suspension bridges represent critical nodes of major transportation systems. Bridge failure during strong earthquakes poses not only a threat of fatalities but causes a substantial interruption of emergency efforts. Although wind induced vibrations have historically been the primary concern in the design of suspension bridges, earthquake effects have also gained importance in recent decades. This study involves ambient vibration testing and sophisticated three-dimensional dynamic finite element analysis and earthquake performance assessment of Fatih Sultan Mehmet and suspension Bo?aziçi bridges in Istanbul under earthquake excitation. Nonlinear time history analysis of 3D finite-element models of Fatih Sultan Mehmet and Bo?aziçi suspension bridges included initial stresses in the cables, suspenders, and towers in equilibrium under dead load conditions. Multi-support scenario earthquake excitation was applied to the structure. Suspension bridges are complex 3-D structures that can exhibit a large number of closely spaced coupled modes of vibration. The large number of closely spaced modes, spatially different ground motion characteristics, and the potential for nonlinear behaviour complicate the seismic response of suspension bridges. Spatial variation of ground motion exhibits itself with different ground motions at supports due to the wave passage, incoherence and local site effects. The source of nonlinear behaviour is due to geometric nonlinearity and the presence of cables that can only carry tensile forces. The natural frequencies of vibration and the corresponding mode shapes in their dead load and live load configurations are determined. Displacement time histories and stresses at critical points of the bridges are computed and their earthquake performance under the action of scenario earthquake are estimated.

  11. Sacrificial bridges for MEMS fabrication

    NASA Astrophysics Data System (ADS)

    Chang, Chao-Min; Chen, Yang-Che; Fong, Chien-Fu; Guu, Yunn-Horng; Chen, Rongshun; Yeh, J. Andrew; Hou, Max T.

    2011-09-01

    This study discusses sacrificial bridges that are used to release MEMS devices. Before being released, sacrificial bridges connect all the component structures into an integral structure. Solder bump bonding is used to mount the MEMS chip on another chip or a printed circuit board (PCB) and to maintain the alignment among all component structures after removal of the sacrificial bridges. Two types of sacrificial bridges were designed, analyzed and fabricated. The fabrication process—which used low resistivity single crystal silicon (SCS) wafers as the device material—was developed to implement the sacrificial bridges. Novel SCS through silicon vias (TSVs), which interconnect stacked chips, was made using the same process. An electrostatic comb drive actuator was fabricated and mounted onto a PCB. The fabricated actuator was tested to demonstrate the feasibility of the fabrication process, sacrificial bridges and SCS TSVs. The results show that the actuator worked well. Its maximum displacement and resonant frequency were 69.9 µm and 406 Hz, respectively. This method is promising for the delivery of a novel 3D system in package for MEMS devices.

  12. Development of inspection robots for bridge cables.

    PubMed

    Yun, Hae-Bum; Kim, Se-Hoon; Wu, Liuliu; Lee, Jong-Jae

    2013-01-01

    This paper presents the bridge cable inspection robot developed in Korea. Two types of the cable inspection robots were developed for cable-suspension bridges and cable-stayed bridge. The design of the robot system and performance of the NDT techniques associated with the cable inspection robot are discussed. A review on recent advances in emerging robot-based inspection technologies for bridge cables and current bridge cable inspection methods is also presented. PMID:24459453

  13. Development of Inspection Robots for Bridge Cables

    PubMed Central

    Kim, Se-Hoon; Lee, Jong-Jae

    2013-01-01

    This paper presents the bridge cable inspection robot developed in Korea. Two types of the cable inspection robots were developed for cable-suspension bridges and cable-stayed bridge. The design of the robot system and performance of the NDT techniques associated with the cable inspection robot are discussed. A review on recent advances in emerging robot-based inspection technologies for bridge cables and current bridge cable inspection methods is also presented. PMID:24459453

  14. Coil Creep and Skew-Quadrupole Field Components in the Tevatron

    SciTech Connect

    Annala, G.; Harding, D.J.; Syphers, M.J.; /Fermilab

    2011-07-11

    During the start-up of Run II of the Tevatron Collider program, several issues surfaced which were not present, or not seen as detrimental, during Run I. These included the repeated deterioration of the closed orbit requiring orbit smoothing every two weeks or so, the inability to correct the closed orbit to desired positions due to various correctors running at maximum limits, regions of systematically strong vertical dipole corrections, and the identification of very strong coupling between the two transverse degrees-of-freedom. It became apparent that many of the problems being experienced operationally were connected to a deterioration of the main dipole magnet alignment, and remedial actions were undertaken. However, the alignment alone was not enough to explain the corrector strengths required to handle transverse coupling. With one exception, strong coupling had generally not been an issue in the Tevatron during Run I. Based on experience with the Main Ring, the Tevatron was designed with a very strong skew quadrupole circuit to compensate any quadrupole alignment and skew quadrupole field errors that might present themselves. The circuit was composed of 48 correctors placed evenly throughout the arcs, 8 per sector, evenly placed in every other cell. Other smaller circuits were installed but not initially needed or commissioned. These smaller circuits were composed of individual skew quadrupole correctors on either side of the long straight sections. These circuits were tuned by first bringing the horizontal and vertical tunes near each other. The skew quadrupoles were then adjusted to minimize tune split, usually to less than 0.003. Initially, the main skew quad circuit (designated T:SQ) could accomplish this global decoupling with only 4% of its possible current, and the smaller circuits were not required at all. The start-up of Run Ib was complicated by what was later discovered to be a rolled triplet quadrupole magnet in one of the Interaction Regions. This led to a reduction in luminosity of nearly 50%, as well as operational confusion until it was uncovered. By the time Collider Run II began, the current needed on the main SQ circuit had increased to 60% of its maximum value. Some of the smaller circuits were also needed to fully decouple the tunes. With this history, several studies were performed early in Run II to search for strong local coupling sources like the triplet quadrupole, but without success. The strong corrector settings were indicative of a much larger problem than a single rolled magnet, and the locality of the error was hard to deduce from the setting of a global correction system. Several possible reasons for the increase in coupling were investigated.

  15. 26. NEW STEEL BRIDGE COMPLETED ASSEMBLED. OLD BRIDGE BELOW. U.S.G.S. ...

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

    26. NEW STEEL BRIDGE COMPLETED ASSEMBLED. OLD BRIDGE BELOW. U.S.G.S. GAGING STATION IN RIGHT BACKGROUND. VIEW LOOKING NORTHEAST - Kaibab Trail Suspension Bridge, Spanning Colorado River, Grand Canyon, Coconino County, AZ

  16. Documentation for assessment of modal pushover-based scaling procedure for nonlinear response history analysis of "ordinary standard" bridges

    USGS Publications Warehouse

    Kalkan, Erol; Kwong, Neal S.

    2010-01-01

    The earthquake engineering profession is increasingly utilizing nonlinear response history analyses (RHA) to evaluate seismic performance of existing structures and proposed designs of new structures. One of the main ingredients of nonlinear RHA is a set of ground-motion records representing the expected hazard environment for the structure. When recorded motions do not exist (as is the case for the central United States), or when high-intensity records are needed (as is the case for San Francisco and Los Angeles), ground motions from other tectonically similar regions need to be selected and scaled. The modal-pushover-based scaling (MPS) procedure recently was developed to determine scale factors for a small number of records, such that the scaled records provide accurate and efficient estimates of 'true' median structural responses. The adjective 'accurate' refers to the discrepancy between the benchmark responses and those computed from the MPS procedure. The adjective 'efficient' refers to the record-to-record variability of responses. Herein, the accuracy and efficiency of the MPS procedure are evaluated by applying it to four types of existing 'ordinary standard' bridges typical of reinforced-concrete bridge construction in California. These bridges are the single-bent overpass, multi span bridge, curved-bridge, and skew-bridge. As compared to benchmark analyses of unscaled records using a larger catalog of ground motions, it is demonstrated that the MPS procedure provided an accurate estimate of the engineering demand parameters (EDPs) accompanied by significantly reduced record-to-record variability of the responses. Thus, the MPS procedure is a useful tool for scaling ground motions as input to nonlinear RHAs of 'ordinary standard' bridges.

  17. Assessment of modal-pushover-based scaling procedure for nonlinear response history analysis of ordinary standard bridges

    USGS Publications Warehouse

    Kalkan, E.; Kwong, N.

    2012-01-01

    The earthquake engineering profession is increasingly utilizing nonlinear response history analyses (RHA) to evaluate seismic performance of existing structures and proposed designs of new structures. One of the main ingredients of nonlinear RHA is a set of ground motion records representing the expected hazard environment for the structure. When recorded motions do not exist (as is the case in the central United States) or when high-intensity records are needed (as is the case in San Francisco and Los Angeles), ground motions from other tectonically similar regions need to be selected and scaled. The modal-pushover-based scaling (MPS) procedure was recently developed to determine scale factors for a small number of records such that the scaled records provide accurate and efficient estimates of “true” median structural responses. The adjective “accurate” refers to the discrepancy between the benchmark responses and those computed from the MPS procedure. The adjective “efficient” refers to the record-to-record variability of responses. In this paper, the accuracy and efficiency of the MPS procedure are evaluated by applying it to four types of existing Ordinary Standard bridges typical of reinforced concrete bridge construction in California. These bridges are the single-bent overpass, multi-span bridge, curved bridge, and skew bridge. As compared with benchmark analyses of unscaled records using a larger catalog of ground motions, it is demonstrated that the MPS procedure provided an accurate estimate of the engineering demand parameters (EDPs) accompanied by significantly reduced record-to-record variability of the EDPs. Thus, it is a useful tool for scaling ground motions as input to nonlinear RHAs of Ordinary Standard bridges.

  18. A strange bridge by Leonardo

    E-print Network

    Huylebrouck, Dirk

    2013-01-01

    On folio 855 recto of the Codex Atlanticus, Leonardo da Vinci drew three 'easily movable' bridges, but one of them is enigmatic: all 'replicas' in Leonardo museums and exhibitions come as a surprise, to say the least, to any engineer or architect whose attention is drawn to it. This is the case for models in Amboise (France), Chicago and Portland (USA), Florence (Italy) and for the one of the traveling exhibition by the Australian company 'Grande Exhibitions' that already visited 40 major cities in the world. All 'replicas' of the bridge model attributed to Leonardo have pillars standing on the deck of the bridge, while the deck is suspended by cables attached on these pillars. At first sight this problem does not catch the attention of the observer, as the bridge seems to be a mixed form of a beam and a suspension bridge, but it was not overlooked by my colleague architect-engineer Dr. Laurens Luyten (Gent, Belgium). Yet, after a TV-interview in Brussels so much pressure was exerted by some of the museum col...

  19. Quantitative analysis of replication-related mutation and selection pressures in bacterial chromosomes and plasmids using generalised GC skew index

    PubMed Central

    2009-01-01

    Background Due to their bi-directional replication machinery starting from a single finite origin, bacterial genomes show characteristic nucleotide compositional bias between the two replichores, which can be visualised through GC skew or (C-G)/(C+G). Although this polarisation is used for computational prediction of replication origins in many bacterial genomes, the degree of GC skew visibility varies widely among different species, necessitating a quantitative measurement of GC skew strength in order to provide confidence measures for GC skew-based predictions of replication origins. Results Here we discuss a quantitative index for the measurement of GC skew strength, named the generalised GC skew index (gGCSI), which is applicable to genomes of any length, including bacterial chromosomes and plasmids. We demonstrate that gGCSI is independent of the window size and can thus be used to compare genomes with different sizes, such as bacterial chromosomes and plasmids. It can suggest the existence of different replication mechanisms in archaea and of rolling-circle replication in plasmids. Correlation of gGCSI values between plasmids and their corresponding host chromosomes suggests that within the same strain, these replicons have reproduced using the same replication machinery and thus exhibit similar strengths of replication strand skew. Conclusions gGCSI can be applied to genomes of any length and thus allows comparative study of replication-related mutation and selection pressures in genomes of different lengths such as bacterial chromosomes and plasmids. Using gGCSI, we showed that replication-related mutation or selection pressure is similar for replicons with similar machinery. PMID:20042086

  20. Nonlinear models of suspension bridges

    NASA Astrophysics Data System (ADS)

    Malik, Josef

    2006-09-01

    Nonlinear variational equations describing one type of suspension bridges are proposed and studied. The variational equations describe the behaviour of road bed, main cables and cable stays. The road bed is described by two functions connected with vertical and horizontal deformation of any cross section. The main cable is considered to be perfectly flexible and inextensible. The cable stays only resist tensile forces. The variational equations are derived from the principle of minimum potential energy. The existence of solution is based on the Brouwer Fixed Point Theorem. The local uniqueness and continuous dependence on the data represented by gravitational forces acting on the road bed are studied. The local results are based on the Implicit Function Theorem for Banach spaces. A certain stability criterion for suspension bridges is formulated and this criterion indicates how to influence the stability of suspension bridges.

  1. Bridge Decomposition of Restriction Measures

    E-print Network

    Tom Alberts; Hugo Duminil-Copin

    2010-07-03

    Motivated by Kesten's bridge decomposition for two-dimensional self-avoiding walks in the upper half plane, we show that the conjectured scaling limit of the half-plane SAW, the SLE(8/3) process, also has an appropriately defined bridge decomposition. This continuum decomposition turns out to entirely be a consequence of the restriction property of SLE(8/3), and as a result can be generalized to the wider class of restriction measures. Specifically we show that the restriction hulls with index less than one can be decomposed into a Poisson Point Process of irreducible bridges in a way that is similar to Ito's excursion decomposition of a Brownian motion according to its zeros.

  2. Detecting global bridges in networks

    E-print Network

    Jensen, Pablo; Karsai, Marton; Venturini, Tommaso; Vespignani, Alessandro; Jacomy, Mathieu; Cointet, Jean-Philippe; Merckle, Pierre; Fleury, Eric

    2015-01-01

    The identification of nodes occupying important positions in a network structure is crucial for the understanding of the associated real-world system. Usually, betweenness centrality is used to evaluate a node capacity to connect different graph regions. However, we argue here that this measure is not adapted for that task, as it gives equal weight to "local" centers (i.e. nodes of high degree central to a single region) and to "global" bridges, which connect different communities. This distinction is important as the roles of such nodes are different in terms of the local and global organisation of the network structure. In this paper we propose a decomposition of betweenness centrality into two terms, one highlighting the local contributions and the other the global ones. We call the latter bridgeness centrality and show that it is capable to specifically spot out global bridges. In addition, we introduce an effective algorithmic implementation of this measure and demonstrate its capability to identify glob...

  3. A Hamiltonian-Entropy Production Connection in the Skew-symmetric Part of a Stochastic Dynamics

    E-print Network

    Hong Qian

    2013-04-06

    The infinitesimal transition probability operator for a continuous-time discrete-state Markov process, $\\mathcal{Q}$, can be decomposed into a symmetric and a skew-symmetric parts. As recently shown for the case of diffusion processes, while the symmetric part corresponding to a gradient system stands for a reversible Markov process, the skew-symmetric part, $\\frac{d}{dt}u(t)=\\mcA u$, is mathematically equivalent to a linear Hamiltonian dynamics with Hamiltonian $H=1/2u^T\\big(\\mcA^T\\mcA)^{1/2}u$. It can also be transformed into a Schr\\"{o}dinger-like equation $\\frac{d}{dt}u=i\\mathcal{H}u$ where the "Hamiltonian" operator $\\mathcal{H}=-i\\mcA$ is Hermitian. In fact, these two representations of a skew-symmetric dynamics emerge natually through singular-value and eigen-value decompositions, respectively. The stationary probability of the Markov process can be expressed as $\\|u^s_i\\|^2$. The motion can be viewed as "harmonic" since $\\frac{d}{dt}\\|u(t)-\\vec{c}\\|^2=0$ where $\\vec{c}=(c,c,...,c)$ with $c$ being a constant. More interestingly, we discover that $\\textrm{Tr}(\\mcA^T\\mcA)=\\sum_{j,\\ell=1}^n \\frac{(q_{j\\ell}\\pi_\\ell-q_{\\ell j}\\pi_j)^2}{\\pi_j\\pi_{\\ell}}$, whose right-hand-side is intimately related to the entropy production rate of the Markov process in a nonequilibrium steady state with stationary distribution $\\{\\pi_j\\}$. The physical implication of this intriguing connection between conservative Hamiltonian dynamics and dissipative entropy production remains to be further explored.

  4. Heat transfer in rotating serpentine passages with trips skewed to the flow

    NASA Technical Reports Server (NTRS)

    Johnson, B. V.; Wagner, J. H.; Steuber, G. D.; Yeh, F. C.

    1992-01-01

    Experiments were conducted to determine the effects of buoyancy and Coriolis forces on heat transfer in turbine blade internal coolant passages. The experiments were conducted with a large scale, multi-pass, heat transfer model with both radially inward and outward flow. Trip strips, skewed at 45 deg to the flow direction, were machined on the leading and trailing surfaces of the radial coolant passages. An analysis of the governing flow equations showed that four parameters influence the heat transfer in rotating passages: coolant-to-wall temperature, rotation number, Reynolds number, and radius-to-passage hydraulic diameter ratio. The first three of these four parameters were varied over ranges which are typical of advanced gas turbine engine operating conditions. Results were correlated and compared to previous results from similar stationary and rotating models with smooth walls and with trip strips normal to the flow direction. The heat transfer coefficients on surfaces, where the heat transfer decreased with rotation and buoyancy, decreased to as low as 40 percent of the value without rotation. However, the maximum values of the heat transfer coefficients with high rotation were only slightly above the highest levels previously obtained with the smooth wall models. It was concluded that (1) both Coriolis and buoyancy effects must be considered in turbine blade cooling designs with trip strips, (2) the effects of rotation are markedly different depending upon the flow direction, and (3) the heat transfer with skewed trip strips is less sensitive to buoyancy than the heat transfer in models with either smooth or normal trips. Therefore, skewed trip strips rather than normal trip strips are recommended and geometry-specific tests are required for accurate design information.

  5. Excitation Methods for Bridge Structures

    SciTech Connect

    Farrar, C.R.; Duffy, T.A.; Cornwell, P.J.; Doebling, S.W.

    1999-02-08

    This paper summarizes the various methods that have been used to excited bridge structures during dynamic testing. The excitation methods fall into the general categories of ambient excitation methods and measured-input excitation methods. During ambient excitation the input to the bridge is not directly measured. In contrast, as the category label implies, measured-input excitations are usually applied at a single location where the force input to the structure can be monitored. Issues associated with using these various types of measurements are discussed along with a general description of the various excitation methods.

  6. Balanced bridge feedback control system

    NASA Technical Reports Server (NTRS)

    Lurie, Boris J. (inventor)

    1990-01-01

    In a system having a driver, a motor, and a mechanical plant, a multiloop feedback control apparatus for controlling the movement and/or positioning of a mechanical plant, the control apparatus has a first local bridge feedback loop for feeding back a signal representative of a selected ratio of voltage and current at the output driver, and a second bridge feedback loop for feeding back a signal representative of a selected ratio of force and velocity at the output of the motor. The control apparatus may further include an outer loop for feeding back a signal representing the angular velocity and/or position of the mechanical plant.

  7. Measuring skew in average surface roughness as a function of surface preparation

    NASA Astrophysics Data System (ADS)

    Stahl, Mark T.

    2015-08-01

    Characterizing surface roughness is important for predicting optical performance. Better measurement of surface roughness reduces polishing time, saves money and allows the science requirements to be better defined. This study characterized statistics of average surface roughness as a function of polishing time. Average surface roughness was measured at 81 locations using a Zygo® white light interferometer at regular intervals during the polishing process. Each data set was fit to a normal and Largest Extreme Value (LEV) distribution; then tested for goodness of fit. We show that the skew in the average data changes as a function of polishing time.

  8. Measuring Skew in Average Surface Roughness as a Function of Surface Preparation

    NASA Technical Reports Server (NTRS)

    Stahl, Mark

    2015-01-01

    Characterizing surface roughness is important for predicting optical performance. Better measurement of surface roughness reduces polishing time, saves money and allows the science requirements to be better defined. This study characterized statistics of average surface roughness as a function of polishing time. Average surface roughness was measured at 81 locations using a Zygo white light interferometer at regular intervals during the polishing process. Each data set was fit to a normal and Largest Extreme Value (LEV) distribution; then tested for goodness of fit. We show that the skew in the average data changes as a function of polishing time.

  9. SoftBridge: A Multimodal Instant Messaging Bridging System

    E-print Network

    Blake, Edwin

    experiments. Keywords--instant messaging, bridging, XML, SOAP, Jabber, web services, speech synthesis, speech in a single chat room. The system is built upon an open Instant Mes- saging platform called Jabber[2]. All Jabber mes- sages are passed as XML, and there is a well defined method for extending the protocol. We

  10. Stochastic epigenetic mutations (DNA methylation) increase exponentially in human aging and correlate with X chromosome inactivation skewing in females

    PubMed Central

    Gentilini, Davide; Garagnani, Paolo; Pisoni, Serena; Bacalini, Maria Giulia; Calzari, Luciano; Mari, Daniela; Vitale, Giovanni; Franceschi, Claudio; Di Blasio, Anna Maria

    2015-01-01

    In this study we applied a new analytical strategy to investigate the relations between stochastic epigenetic mutations (SEMs) and aging. We analysed methylation levels through the Infinium HumanMethylation27 and HumanMethylation450 BeadChips in a population of 178 subjects ranging from 3 to 106 years. For each CpG probe, epimutated subjects were identified as the extreme outliers with methylation level exceeding three times interquartile ranges the first quartile (Q1-(3 × IQR)) or the third quartile (Q3+(3 × IQR)). We demonstrated that the number of SEMs was low in childhood and increased exponentially during aging. Using the HUMARA method, skewing of X chromosome inactivation (XCI) was evaluated in heterozygotes women. Multivariate analysis indicated a significant correlation between log(SEMs) and degree of XCI skewing after adjustment for age (? = 0.41; confidence interval: 0.14, 0.68; p-value = 0.0053). The PATH analysis tested the complete model containing the variables: skewing of XCI, age, log(SEMs) and overall CpG methylation. After adjusting for the number of epimutations we failed to confirm the well reported correlation between skewing of XCI and aging. This evidence might suggest that the known correlation between XCI skewing and aging could not be a direct association but mediated by the number of SEMs. PMID:26342808

  11. Wind effect on long span bridge

    E-print Network

    Zhang, Xi, M. Eng. Massachusetts Institute of Technology

    2012-01-01

    This thesis has studied different types of reactions of long span bridge under wind load, such as vortex shedding, flutter and buffeting. Since all of these conditions have the chance to damage bridge structure, we calculate ...

  12. 28. Under ninth bridge, view to concrete dam and eighth ...

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

    28. Under ninth bridge, view to concrete dam and eighth bridge in background during heavy rain, view to the SW. - Vicksburg National Military Park Roads & Bridges, Melan Arch Bridges, Spanning various tributaries at Confederate Avenue, Vicksburg, Warren County, MS

  13. 12. View of bridge seat at north abutment with expansion ...

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

    12. View of bridge seat at north abutment with expansion bearing, under bridge at northwest corner of bridge, looking from the east - Bridge No. 4900, Spanning Root River at Trunk Highway 16, Rushford, Fillmore County, MN

  14. STUDENT STEEL BRIDGE COMPETITION The mission of the Student Steel Bridge Competition (SSBC) is to supplement

    E-print Network

    Stuart, Steven J.

    1 STUDENT STEEL BRIDGE COMPETITION 2012 RULES #12;2 MISSION The mission of the Student Steel Bridge individuals in the Student Steel Bridge Competition without regard to race, ethnicity, religion, age, gender, sexual orientation, nationality, or physical challenges. Bridge teams should be inclusive and open

  15. 77 FR 53251 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-31

    ... Federal Highway Administration Annual Materials Report on New Bridge Construction and Bridge.... L. 109-59; 119 Stat. 1144) continued the highway bridge program to enable States to improve the condition of their highway bridges over waterways, other topographical barriers, other highways,...

  16. 75 FR 62181 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-07

    ... Federal Highway Administration Annual Materials Report on New Bridge Construction and Bridge.... L. 109-59; 119 Stat. 1144) continued the highway bridge program to enable States to improve the condition of their highway bridges over waterways, other topographical barriers, other highways,...

  17. 76 FR 55160 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-06

    ... Federal Highway Administration Annual Materials Report on New Bridge Construction and Bridge.... L. 109-59; 119 Stat. 1144) continued the highway bridge program to enable States to improve the condition of their highway bridges over waterways, other topographical barriers, other highways,...

  18. Bridge Programs in Illinois: Results of the 2010 Illinois Bridge Status Survey

    ERIC Educational Resources Information Center

    Taylor, J. L.; Harmon, T.

    2010-01-01

    This report provides a summary of major results of the Illinois Bridge Status Survey, administered online between April and June 2010. The purpose of the survey was to understand the extent to which bridge programs are being implemented in Illinois, as well as to build an online directory of bridge programs. Bridge programs are an emerging…

  19. Over the Ramp: Building Bridges

    ERIC Educational Resources Information Center

    Sutton, Mary

    2007-01-01

    TheatreWorks is the third largest theatre in the San Francisco bay area. Through the usual educational programs that $6 million companies tend to offer, it has reached over 100,000 students of all ages in the past 8 years. The TheatreWorks Bridges Projects, however, are special. They are intricate and expansive, work with multiple community…

  20. Bridging the Multimedia Generation Gap.

    ERIC Educational Resources Information Center

    Hurn, Janet; Thibeault, Nancy

    This paper outlines efforts at Miami University (Middletown, Ohio) to bridge the "generation gap" between students who are comfortable using computer technologies and the faculty and staff who are reluctant to use them. Two Instructional Technology Fairs were held on campus (in Springs 1995 and 1996) to show faculty, staff, students, and community…

  1. Bike/ped bridge CAMPUSDRIVEWEST

    E-print Network

    Bike/ped bridge Bike/ped underpass ELCAM INO REAL ELCAM INO REAL GALVEZST SERRA MALL CAM PUSDREAST & Transportation Services (P&TS) Montag Hall Stock Farm lot Parking Structure 5 (PS5) EH&S Stanford West Apartments 1000 1101 900 C Line C Effective Oct.6,2014 #12;ELCAM INO REAL M INO REAL GALVEZST SERRA MALL CAM

  2. A Bridge to the Future

    ERIC Educational Resources Information Center

    Anderson, Richard

    2008-01-01

    Career and technical education (CTE) has a promising future at Darlington (WI) High School. In this article, the author describes how a class bridge project became a real-world, project-based learning opportunity involving higher-level thinking skills that are at the core of CTE at his school. It began when a local citizen approached him at the…

  3. Evaluation of Summer Bridge Programs

    ERIC Educational Resources Information Center

    Garcia, Lisa D.; Paz, Chiara C.

    2009-01-01

    Many colleges and universities in the United States offer summer programs for their incoming students. While programs are structured and administered in a variety of ways and target various student populations, the most common type of summer bridge program aims to serve historically underrepresented students and students of low socioeconomic…

  4. Building Cultural Bridges. Research Brief

    ERIC Educational Resources Information Center

    Burton, Ella

    2007-01-01

    The book "Building Cultural Bridges" is designed to increase multi-cultural awareness and sensitivity. There are supplemental materials available that include a leader's guide, reproducible student workbook, readings, worksheets, and activities. This material is recommended for use with students in grades 7-12. The materials included with this…

  5. Bridging The Gap: From Biometrics to Forensics

    E-print Network

    Bridging The Gap: From Biometrics to Forensics Anil K. Jain Michigan State University http://biometrics.cse.msu.edu February 2, 2015 1 #12;Outline 2 · Questions about identity · What is biometrics? · Why biometric recognition? · Automatic biometric recognition · Challenges · Bridging the gap #12;Bridging The Gap

  6. Pedestrian excitation of bridges D E Newland

    E-print Network

    Newland, David E.

    (alternatively, mass of pedestrians per unit length of bridge) mr non-dimensional mass ratio ^ abm=M m0 mass per person M modal mass of bridge (alternatively, mass of bridge per unit length) Sc Scruton number Scp to high vibration levels. The main assumption is that the movement of a pedestrian's centre of mass has

  7. Remediation: Higher Education's Bridge to Nowhere

    ERIC Educational Resources Information Center

    Complete College America, 2012

    2012-01-01

    The intentions were noble. It was hoped that remediation programs would be an academic bridge from poor high school preparation to college readiness. Sadly, remediation has become instead higher education's "Bridge to Nowhere." This broken remedial bridge is travelled by some 1.7 million beginning students each year, most of whom will not reach…

  8. Bridge Detection By Road Detection Jeff Kaufman

    E-print Network

    Danner, Andrew

    Bridge Detection By Road Detection Jeff Kaufman cbr@sccs.swarthmore.edu 1 Introduction It is useful, with local min- ima: cells from which there is no direction of descent. A common cause of this is bridges. The area over which a bridge passes shows up in the digital elevation as being of a height greater than

  9. River Lagan Lagan Bridge (M3)

    E-print Network

    Gribakin, Gleb

    River Lagan Stew art Street Pakenham St. Ormeau Road PSNI Odyssey/W5 Lagan Bridge (M3) Royal Avenue Church Lane BridgeSt. HillStreet Skipper Street Ann Street Gordon Street Talbot Street DunbarStreet Gt. Glengall Street Divis Street Castle Street Durham Street BoyneBridge BarrackStreet BedfordStreet Linenhall

  10. Building Bridges One Line at a Time

    ERIC Educational Resources Information Center

    Grigsby, Cathy Murray

    2012-01-01

    In this article, first-grade students were taught the different kinds of lines that were part of the construction of various bridges--the curved lines of the arches of stone bridges, straight lines connecting the cables of a suspension bridge, vertical lines, horizontal lines, and so on. They gained practice in drawing structures and in fine brush…

  11. 3D Bridge Construction Author: Yuan Xie

    E-print Network

    Schroeder, Peter

    3D Bridge Construction Author: Yuan Xie Mentor: Dr. Peter Schröder and Steven Schkolne California for constructing various kinds of bridges. This project involves constructing basic elements of a bridge architects to design and construct large complex structures in a three-dimensional space, and interact

  12. Dynamic Testing of Alfred Zampa Memorial Bridge

    E-print Network

    2008-01-01

    there were no construction activities on the bridge and thusconstruction of the AZMB, the strait was spanned by two steel truss bridges,and construction of the AZMB incorporates several innovative structural features that have never been used previously for a suspension bridge

  13. MARKOVIAN BRIDGES: WEAK CONTINUITY AND PATHWISE CONSTRUCTIONS

    E-print Network

    MARKOVIAN BRIDGES: WEAK CONTINUITY AND PATHWISE CONSTRUCTIONS LO¨IC CHAUMONT AND GER´ONIMO URIBE´evy's construction of the Brownian bridge: given a Brownian motion B starting at zero, let bx,y,t s = x + Bs - Bt´evy's Gaussian construction of the Brownian bridge is of limited applicability in the context of Markov processes

  14. TAYLOR BRIDGE -FIELD ASSESSMENT Doug STEWARTi

    E-print Network

    construction materials relative to the conventionally reinforced portions of the bridge. Design philosophiesTAYLOR BRIDGE - FIELD ASSESSMENT Doug STEWARTi , Emile SHEHATAi , Gamil TADROS2 and Sami RIZKALLA2 the Taylor "smart" Bridge utilizing fibre reinforced polymer (FRP) reinforcing materials as the primary

  15. 77 FR 16784 - General Bridge Regulation; Amendment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-22

    ...determining whether an unused bridge is an unreasonable obstruction...email Mr. Chris Jaufmann, Bridge Program, U.S. Coast Guard...you have questions on viewing material in the docket, call Renee...alteration or removal of unused bridges. This rulemaking would...

  16. ADVANCED COMPOSITE MATERIALS FOR BRIDGES Sami RIZKALLA

    E-print Network

    the Canadian experience in the design and construction of highway bridges built with these new materials. The paper reviews the design and construction ofthe Taylor Bridge inHeadingley, Manitoba, where FRPs were and provide design guidelines for the construction details used in the bridge[l]. The following section

  17. Recent Innovation for Concrete Highway Bridges

    E-print Network

    generation of concrete highway bridges has recently been built in Canada using new design concepts at the Technical University of Nova Scotia. The paper also describes the design and the development of a new bridgeRecent Innovation for Concrete Highway Bridges S. H. Rizkalla' and A. A. Mufti2 Abstract A new

  18. 49 CFR 236.713 - Bridge, movable.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Bridge, movable. 236.713 Section 236.713 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Bridge, movable. That section of a structure bridging a navigable waterway so designed that it may...

  19. 49 CFR 236.713 - Bridge, movable.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Bridge, movable. 236.713 Section 236.713 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Bridge, movable. That section of a structure bridging a navigable waterway so designed that it may...

  20. 49 CFR 236.713 - Bridge, movable.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Bridge, movable. 236.713 Section 236.713 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Bridge, movable. That section of a structure bridging a navigable waterway so designed that it may...

  1. 49 CFR 236.713 - Bridge, movable.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Bridge, movable. 236.713 Section 236.713 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Bridge, movable. That section of a structure bridging a navigable waterway so designed that it may...

  2. Bridges 2013 Poetry Anthology Sarah Glaz, Editor

    E-print Network

    Glaz, Sarah

    Bridges 2013 Poetry Anthology Sarah Glaz, Editor Contents Introduction Poems by Bridges Enschede poems with commentary from FRED AND BLOSSOM: So How Do You Design an Aeroplane 5 Centres of Gravity 1934;Eveline Pye Solving Problems 27 Numerical Landscape 28 Statistics 29 Love of Algebra 30 Poems by Bridges

  3. 49 CFR 236.713 - Bridge, movable.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Bridge, movable. 236.713 Section 236.713 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Bridge, movable. That section of a structure bridging a navigable waterway so designed that it may...

  4. Skewness and kurtosis as indicators of non-Gaussianity in galactic foreground maps

    NASA Astrophysics Data System (ADS)

    Ben-David, Assaf; von Hausegger, Sebastian; Jackson, Andrew D.

    2015-11-01

    Observational cosmology is entering an era in which high precision will be required in both measurement and data analysis. Accuracy, however, can only be achieved with a thorough understanding of potential sources of contamination from foreground effects. Our primary focus will be on non-Gaussian effects in foregrounds. This issue will be crucial for coming experiments to determine B-mode polarization. We propose a novel method for investigating a data set in terms of skewness and kurtosis in locally defined regions that collectively cover the entire sky. The method is demonstrated on two sky maps: (i) the SMICA map of Cosmic Microwave Background fluctuations provided by the Planck Collaboration and (ii) a version of the Haslam map at 408 MHz that describes synchrotron radiation. We find that skewness and kurtosis can be evaluated in combination to reveal local physical information. In the present case, we demonstrate that the statistical properties of both maps in small local regions are predominantly Gaussian. This result was expected for the SMICA map. It is surprising that it also applies for the Haslam map given its evident large scale non-Gaussianity. The approach described here has a generality and flexibility that should make it useful in a variety of astrophysical and cosmological contexts.

  5. Changes of skewness and sharpness of partially coherent decentered annular beams on propagation

    NASA Astrophysics Data System (ADS)

    Yang, Ting; Ji, Xiaoling; Li, Xiaoqing; Zhang, Hao; Wang, Tao

    2016-01-01

    Changes of skewness and sharpness of partially coherent decentered annular beams (PCDA beams) on propagation both in free space and in oceanic turbulence are studied. Based on the Wigner distribution function, the analytical expressions for the skewness parameter A and the kurtosis parameter K of PCDA beams are derived. The analytical expression for the oceanic turbulence parameter T? related to K is also derived, and characteristics of T? are examined. It is found that the behaviors of A and K in oceanic turbulence are quite different from those in free space. In free space, the mass of the intensity distribution may move from one side of the centroid position axis yc to another side at a certain propagation distance z0, and z0 is independent of the correlation parameter ?. The mass of the intensity distribution is concentrated on one side of yc on propagation only for a poorly coherent beam in free space, but it is always this situation for different value of ? when oceanic turbulence is not weak. In free space, it takes a leptokurtic profile in the far field, and a Gaussian profile appears only for a poorly coherent beam. However, in oceanic turbulence it always reaches a Gaussian profile for different value of ? in the far field.

  6. Fourier transform assisted deconvolution of skewed peaks in complex multi-dimensional chromatograms.

    PubMed

    Hanke, Alexander T; Verhaert, Peter D E M; van der Wielen, Luuk A M; Eppink, Michel H M; van de Sandt, Emile J A X; Ottens, Marcel

    2015-05-15

    Lower order peak moments of individual peaks in heavily fused peak clusters can be determined by fitting peak models to the experimental data. The success of such an approach depends on two main aspects: the generation of meaningful initial estimates on the number and position of the peaks, and the choice of a suitable peak model. For the detection of meaningful peaks in multi-dimensional chromatograms, a fast data scanning algorithm was combined with prior resolution enhancement through the reduction of column and system broadening effects with the help of two-dimensional fast Fourier transforms. To capture the shape of skewed peaks in multi-dimensional chromatograms a formalism for the accurate calculation of exponentially modified Gaussian peaks, one of the most popular models for skewed peaks, was extended for direct fitting of two-dimensional data. The method is demonstrated to successfully identify and deconvolute peaks hidden in strongly fused peak clusters. Incorporation of automatic analysis and reporting of the statistics of the fitted peak parameters and calculated properties allows to easily identify in which regions of the chromatograms additional resolution is required for robust quantification. PMID:25841612

  7. Hematopoietic lineage skewing and intestinal epithelia degeneration in aged mice with telomerase RNA component deletion.

    PubMed

    Chen, Jichun; Bryant, Mark A; Dent, James J; Sun, Yu; Desierto, Marie J; Young, Neal S

    2015-12-01

    A deletion of a telomerase RNA component (Terc(-/-)) in C57BL/6 (B6) mice resulted in hematopoietic lineage skewing with increased neutrophils and CD11b(+) myeloid cells and decreased red blood cells and CD45R(+) B lymphocytes when animals reach ages older than 12months. There was no decline in bone marrow (BM) c-Kit(+)Sca-1(+)Lin(-) (KSL) cells in old Terc(-/-) mice, and the lineage skewing phenomenon was not transferred when BM cells from old Terc(-/-) donors were transplanted into young B6 recipients. Necropsy and histological examinations found minimal to no change in the lung, spleen and liver but detected severe epithelia degeneration, ulceration and infection in small and large intestines, leading to enteritis, typhlitis and colitis in old Terc(-/-) mice. In a mouse model of dextran-sulfate-sodium-induced typhlitis and colitis, development of intestinal pathology was associated with increases in neutrophils and CD11b(+) myeloid cells and a decrease in CD45R(+) B cells, similar to those observed in old Terc(-/-) mice. Treatment of 11-13month old Terc(-/-) mice with antibiotic trimethoprim-sulfa water reduced neutrophils and myeloid cells and increased B lymphocytes in the blood, indicating that mitigation of intestinal infection and inflammation could alleviate hematological abnormalities in old Terc(-/-) animals. PMID:26523501

  8. Heat transfer in rotating serpentine passages with trips skewed to the flow

    NASA Technical Reports Server (NTRS)

    Johnson, B. V.; Wagner, J. H.; Steuber, G. D.; Yeh, F. C.

    1992-01-01

    Experiments were conducted to determine the effects of buoyancy and Coriolis forces on heat transfer in turbine blade internal coolant passages. The experiments were conducted with a large scale, multi-pass heat transfer model with both radially inward and outward flow. An analysis of the governing flow equations showed that four parameters influence the heat transfer in rotating passages: coolant-to-wall temperature, rotation number, Reynolds number, and radius-to-passage hydraulic diameter ratio. Results were correlated and compared to previous results from similar stationary and rotating models with smooth walls and with trip strips normal to the flow direction. It was concluded that (1) both Coriolis and buoyancy must be considered in turbine blade cooling designs with trip strips, (2) the effects of rotation are markedly different depending upon the flow direction, and (3) the heat transfer with skewed trip strips is less sensitive to buoyancy than the heat transfer models with either smooth or normal trips. Therefore, skewed trip strips rather than normal trip strips are recommended and geometry-specific tests are required for accurate design.

  9. Skew Young diagram method in spectral decomposition of integrable lattice models

    E-print Network

    Anatol N. Kirillov; Atsuo Kuniba; Tomoki Nakanishi

    1996-07-19

    The spectral decomposition of the path space of the vertex model associated to the vector representation of the quantized affine algebra $U_q(\\hat{sl}_n)$ is studied. We give a one-to-one correspondence between the spin configurations and the semi-standard tableaux of skew Young diagrams. As a result we obtain a formula of the characters for the degeneracy of the spectrum in terms of skew Schur functions. We conjecture that our result describes the $sl_n$-module contents of the Yangian $Y(sl_n)$-module structures of the level 1 integrable modules of the affine Lie algebra $\\hat{sl}_n$. An analogous result is obtained also for a vertex model associated to the quantized twisted affine algebra $U_q(A^{(2)}_{2n})$, where $Y(B_n)$ characters appear for the degeneracy of the spectrum. The relation to the spectrum of the Haldane-Shastry and the Polychronakos models are also discussed.

  10. Fuel cell plates with skewed process channels for uniform distribution of stack compression load

    DOEpatents

    Granata, Jr., Samuel J. (Greensburg, PA); Woodle, Boyd M. (North Huntingdon Township, Westmoreland County, PA)

    1989-01-01

    An electrochemical fuel cell includes an anode electrode, a cathode electrode, an electrolyte matrix sandwiched between electrodes, and a pair of plates above and below the electrodes. The plate above the electrodes has a lower surface with a first group of process gas flow channels formed thereon and the plate below the electrodes has an upper surface with a second group of process gas flow channels formed thereon. The channels of each group extend generally parallel to one another. The improvement comprises the process gas flow channels on the lower surface of the plate above the anode electrode and the process gas flow channels on the upper surface of the plate below the cathode electrode being skewed in opposite directions such that contact areas of the surfaces of the plates through the electrodes are formed in crisscross arrangements. Also, the plates have at least one groove in areas of the surfaces thereof where the channels are absent for holding process gas and increasing electrochemical activity of the fuel cell. The groove in each plate surface intersects with the process channels therein. Also, the opposite surfaces of a bipolar plate for a fuel cell contain first and second arrangements of process gas flow channels in the respective surfaces which are skewed the same amount in opposite directions relative to the longitudinal centerline of the plate.

  11. Structural Bridges through Fold Space.

    PubMed

    Edwards, Hannah; Deane, Charlotte M

    2015-09-01

    Several protein structure classification schemes exist that partition the protein universe into structural units called folds. Yet these schemes do not discuss how these units sit relative to each other in a global structure space. In this paper we construct networks that describe such global relationships between folds in the form of structural bridges. We generate these networks using four different structural alignment methods across multiple score thresholds. The networks constructed using the different methods remain a similar distance apart regardless of the probability threshold defining a structural bridge. This suggests that at least some structural bridges are method specific and that any attempt to build a picture of structural space should not be reliant on a single structural superposition method. Despite these differences all representations agree on an organisation of fold space into five principal community structures: all-?, all-? sandwiches, all-? barrels, ?/? and ? + ?. We project estimated fold ages onto the networks and find that not only are the pairings of unconnected folds associated with higher age differences than bridged folds, but this difference increases with the number of networks displaying an edge. We also examine different centrality measures for folds within the networks and how these relate to fold age. While these measures interpret the central core of fold space in varied ways they all identify the disposition of ancestral folds to fall within this core and that of the more recently evolved structures to provide the peripheral landscape. These findings suggest that evolutionary information is encoded along these structural bridges. Finally, we identify four highly central pivotal folds representing dominant topological features which act as key attractors within our landscapes. PMID:26372166

  12. Structural Bridges through Fold Space

    PubMed Central

    Edwards, Hannah; Deane, Charlotte M.

    2015-01-01

    Several protein structure classification schemes exist that partition the protein universe into structural units called folds. Yet these schemes do not discuss how these units sit relative to each other in a global structure space. In this paper we construct networks that describe such global relationships between folds in the form of structural bridges. We generate these networks using four different structural alignment methods across multiple score thresholds. The networks constructed using the different methods remain a similar distance apart regardless of the probability threshold defining a structural bridge. This suggests that at least some structural bridges are method specific and that any attempt to build a picture of structural space should not be reliant on a single structural superposition method. Despite these differences all representations agree on an organisation of fold space into five principal community structures: all-?, all-? sandwiches, all-? barrels, ?/? and ? + ?. We project estimated fold ages onto the networks and find that not only are the pairings of unconnected folds associated with higher age differences than bridged folds, but this difference increases with the number of networks displaying an edge. We also examine different centrality measures for folds within the networks and how these relate to fold age. While these measures interpret the central core of fold space in varied ways they all identify the disposition of ancestral folds to fall within this core and that of the more recently evolved structures to provide the peripheral landscape. These findings suggest that evolutionary information is encoded along these structural bridges. Finally, we identify four highly central pivotal folds representing dominant topological features which act as key attractors within our landscapes. PMID:26372166

  13. 49 CFR 237.111 - Review of bridge inspection reports.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Review of bridge inspection reports. 237.111... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.111 Review of bridge inspection reports. Bridge inspection reports shall be reviewed by railroad bridge supervisors and...

  14. 49 CFR 237.111 - Review of bridge inspection reports.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Review of bridge inspection reports. 237.111... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.111 Review of bridge inspection reports. Bridge inspection reports shall be reviewed by railroad bridge supervisors and...

  15. 49 CFR 237.111 - Review of bridge inspection reports.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Review of bridge inspection reports. 237.111... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.111 Review of bridge inspection reports. Bridge inspection reports shall be reviewed by railroad bridge supervisors and...

  16. 49 CFR 237.109 - Bridge inspection records.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Bridge inspection records. 237.109 Section 237.109..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.109 Bridge inspection records... performed on those bridges under this part. (b) Each record of an inspection under the bridge...

  17. 49 CFR 237.111 - Review of bridge inspection reports.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Review of bridge inspection reports. 237.111... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.111 Review of bridge inspection reports. Bridge inspection reports shall be reviewed by railroad bridge supervisors and...

  18. 49 CFR 237.109 - Bridge inspection records.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Bridge inspection records. 237.109 Section 237.109..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.109 Bridge inspection records... performed on those bridges under this part. (b) Each record of an inspection under the bridge...

  19. 49 CFR 237.111 - Review of bridge inspection reports.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Review of bridge inspection reports. 237.111... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.111 Review of bridge inspection reports. Bridge inspection reports shall be reviewed by railroad bridge supervisors and...

  20. 49 CFR 237.109 - Bridge inspection records.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Bridge inspection records. 237.109 Section 237.109..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.109 Bridge inspection records... performed on those bridges under this part. (b) Each record of an inspection under the bridge...

  1. 49 CFR 237.109 - Bridge inspection records.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Bridge inspection records. 237.109 Section 237.109..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.109 Bridge inspection records... performed on those bridges under this part. (b) Each record of an inspection under the bridge...

  2. 49 CFR 237.109 - Bridge inspection records.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Bridge inspection records. 237.109 Section 237.109..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.109 Bridge inspection records... performed on those bridges under this part. (b) Each record of an inspection under the bridge...

  3. g g gg g gSustainable Bridge Design & Health MonitoringSustainable Bridge Design & Health Monitoring Whatever Happened to LongWhatever Happened to Long--Term Bridge DesignTerm Bridge Design??

    E-print Network

    Hines, Eric

    g g gg g gSustainable Bridge Design & Health MonitoringSustainable Bridge Design & Health Monitoring Whatever Happened to LongWhatever Happened to Long--Term Bridge DesignTerm Bridge Design?? Why now to include over 500,000 bridges. At the time many of these bridges were designed based on a design life

  4. Problems associated with nondestructive evaluation of bridges

    NASA Astrophysics Data System (ADS)

    Prine, David W.

    1995-05-01

    The US has 542,000 bridges that consume billions of dollars per year in construction, rehabilitation, and maintenance funds and which are the lifelines of US commerce. The 1992 ISTEA (Intermodal Surface Transportation Efficiency Act) mandates the implementation of a quantitative computerized bridge management system by 1996. A prime need of such a system are quantitative bridge inspection methods to feed accurate reliable condition information to the huge database of bridges. Nondestructive evaluation (NDE) will fill a critical need in the implementation of effective bridge management. However, many serious barriers exist to the widespread routine application of this technology to bridges. This paper provides an overview of the typical problems associated with applying NDE to bridges.

  5. Numerical solution for the velocity-derivative skewness of a low Reynolds-number turbulent-like decaying Navier-Stokes flow

    NASA Technical Reports Server (NTRS)

    Deissler, Robert G.

    1991-01-01

    The variation of the velocity-derivative skewness of a Navier-Stokes flow as the Reynolds number goes toward zero is calculated numerically. The value of the skewness, which has been somewhat controversial, is shown to become small at low Reynolds numbers.

  6. All porcelain anterior veneer bridges.

    PubMed

    Denissen, H W; Gardner, F B; Wijnhoff, G F; Veldhuis, H A; Kalk, W

    1990-01-01

    The introduction of new porcelain materials used in combination with vastly improved bonding materials and techniques have virtually revolutionized the use of conservative esthetic bonded prosthetic restorations fabricated without the need for metal substructures. Missing anterior teeth in selected cases may be replaced by all porcelain veneer bridges that are accomplished with more conservation of natural tooth structure of the abutment teeth as compared to traditional procedures. A total of 12 all porcelain veneer bridges were monitored for varying periods up to 24 months postoperatively, during which time no fractures occurred. The authors have attributed this high early success rate primarily to several factors, namely (1) case selection, (2) bulk of porcelain at the sides of the major connectors, and (3) adjustment of occlusion and articulation with the opposing teeth. PMID:2098061

  7. Halliburton Composite Bridge Plug Assembly

    SciTech Connect

    Starbuck, J.M.; Luttrell, C.R.; Aramayo, G.

    2005-01-15

    The overall objectives of this CRADA were to assist Halliburton in analyzing a composite bridge plug and to determine why their original design was failing in the field. In Phase 1, finite element analyses were done on the original composite slip design and several alternative designs. The composite slip was the component in the bridge plug that was failing. The finite element code ABAQUS was used for these calculations and I-DEAS was used as the pre- and post-processor in the analyses. Several different designs and materials were analyzed and recommendations were made towards improving the design. In Phase 2, the objective was to develop finite element models that would accurately represent the deformations in the entire all-composite 4-1/2' diameter bridge plug assembly. The finite element code LS-DYNA was used and the results from this effort were intended to expand Halliburton's composite design and analysis capabilities with regard to developing future composite components for downhole tools. In addition to the finite element modeling, this effort involved the utilization of micromechanics to determine the necessary composite material properties that were needed as input for finite element codes.

  8. Scour assessment at bridges from Flag Point to Million Dollar Bridge, Copper River Highway, Alaska

    USGS Publications Warehouse

    Brabets, T.P.

    1994-01-01

    Twelve bridges are located along the Copper River Highway from Flag Point (Mile 27) to lhe Million Dollar Bridge (Mile 48). These bridges cross all or parts of the Copper River. Channel scour at these bridges was assessed by collecting and analyzing discharge and sediment data, analyzing aerial photography for eight different years, surveying and comparing cross sections, and utilizing scour equations. Between 1968 and 1992, scour occurring at Bridge 331 has formed two distinct channels at the bridge. The channel at Bridge 1187 has remained relatively unchanged between 1968 and 1992. During this same time period, the channel at Bridge 332 appears to have gradually filled. However, during the 1992 runoff season, the channel at this bridge scoured significantly, probably because of its unstable nature. The most significant scour has occurred at Bridge 342. A high-water period in 1981 probably shifted much of the flow of the Copper River through this bridge. As a result, severe contraction scour occurred which required major repairs to the bridge. During 1991 and 1992, the approach channel to Bridge 342 has been migrating, causing scour in the left side of the channel. Bed material at the Million Dollar Bridge consists of hard unweathered boulders nested in dense gravel. Because of this type of erosion-resistant material, no significant scour has occurred at this site. Contraction scour equations overestimated the mean depth of flow at Bridge 331 by 2.6 to 5.0 ft, but were within 1.0 ft of the mean depth of flow for Bridge 1187. The local scour equations generally overestimated local scour at both Bridge 331 and Bridge 1187. The accuracy of some equations was probably affected because water velocities could not be obtained upstream from the piers.

  9. Shift Dependent Skew Quadrupole in Advanced Light SourceElliptically Polarizing Undulators, Cause and Corrections

    SciTech Connect

    Marks, Steve; Prestemon, Soren; Robin, David; Schlueter, Ross D.; Steier, Christoph; Wolski, Andrew; Jung, Jin-Young; Chubar, Oleg

    2005-11-29

    Three elliptically polarizing undulators (EPU) are installed and operational at the Advanced Light Source (ALS); the most recent was installed in April 2005. Operational experience has shown a variation in electron beam size which correlates with the EPU's magnetic quadrant shifts used to vary polarization. Storage ring electron dynamics studies pointed to the existence of a shift dependent skew quadrupole (SQ) component generated within the EPUs. Detailed magnetic and mechanical measurements demonstrated that the field errors were the result of systematic individual magnetic block displacements which vary with quadrant shift. This paper will discuss the results of electron dynamics studies, magnetic and mechanical measurements, design modifications planned for future EPUs to eliminate the SQ source, and the design and implementation of SQ compensation coils.

  10. Nonlinear free flexural vibrations of functionally graded rectangular and skew plates under thermal environments

    E-print Network

    Sundararajan, N; Ganapathi, M; 10.1016/j.finel.2005.06.001

    2011-01-01

    The nonlinear formulation developed based on von Karman's assumptions is employed to study the free vibration characteristics of functionally graded material (FGM) plates subjected to thermal environment. Temperature field is assumed to be a uniform distribution over the plate surface and varied in the thickness direction. The material is assumed to be temperature dependent and graded in the thickness direction according to the power-law distribution in terms of volume fractions of the constituents. The effective material properties are estimated from the volume fractions and the material properties of the constituents using Mori-Tanaka homogenization method. The nonlinear governing equations obtained using Lagrange's equations of motion are solved using finite element procedure coupled with the direct iteration technique. The variation of nonlinear frequency ratio with amplitude is highlighted considering various parameters such as gradient index, temperature, thickness and aspect ratios, and skew angle. For...

  11. Natural Connection with Totally Skew-Symmetric Torsion on Riemannian Almost Product Manifolds

    E-print Network

    Dimitar Mekerov; Mancho Manev

    2011-02-22

    On a Riemannian almost product manifold $(M,P,g)$ we consider a linear connection preserving the almost product structure $P$ and the Riemannian metric $g$ and having a totally skew-symmetric torsion. We determine the class of the manifolds $(M,P,g)$ admitting such a connection and prove that this connection is unique in terms of the covariant derivative of $P$ with respect to the Levi-Civita connection. We find a necessary and sufficient condition the curvature tensor of the considered connection to have similar properties like the ones of the K\\"ahler tensor in Hermitian geometry. We pay attention to the case when the torsion of the connection is parallel. We consider this connection on a Riemannian almost product manifold $(G,P,g)$ constructed by a Lie group $G$.

  12. Nondestructive evaluation techniques for enhanced bridge inspection

    SciTech Connect

    Thomas, G.; Benson, S.; Durbin, P.; Del Grande, N.; Haskins, J.; Brown, A.; Schneberk, D.

    1993-10-01

    Nondestructive evaluation of bridges is a critical aspect in the US aging infrastructure problem. For example in California there are 26,000 bridges, 3000 are made of steel, and of the steel bridges, 1000 are fracture critical. California Department of Transportation (Caltrans), Federal Highway Administration, and Lawrence Livermore National Laboratory (LLNL) are collaborating to develop and field NDE techniques to improve bridge inspections. We have demonstrated our NDE technologies on several bridge inspection applications. An early collaboration was to ultrasonically evaluate the steel pins in the E-9 pier on the San Francisco Bay Bridge. Following the Loma-Prieta earthquake in 1989 and the road way collapse at the E-9 pier, a complete nondestructive evaluation was conducted by Caltrans inspectors and several ultrasonic indications were noted. LLNL worked with Caltrans to help identify the source of these reflections. Another project was to digitally enhance high energy radiographs of bridge components such as cable end caps. We demonstrated our ability to improve the detection of corrosion and fiber breakage inside the end cap. An extension of this technology is limited view computer tomography (CT). We implemented our limited view CT software and produced cross-sectional views of bridge cables from digitized radiographic films. Most recently, we are developing dual band infrared imaging techniques to assess bridge decks for delaminations. We have demonstrated the potential of our NDE technology for enhancing the inspection of the country`s aging bridges.

  13. On the Empirical Importance of the Conditional Skewness Assumption in Modelling the Relationship between Risk and Return

    NASA Astrophysics Data System (ADS)

    Pipie?, M.

    2008-09-01

    We present the results of an application of Bayesian inference in testing the relation between risk and return on the financial instruments. On the basis of the Intertemporal Capital Asset Pricing Model, proposed by Merton we built a general sampling distribution suitable in analysing this relationship. The most important feature of our assumptions is that the skewness of the conditional distribution of returns is used as an alternative source of relation between risk and return. This general specification relates to Skewed Generalized Autoregressive Conditionally Heteroscedastic-in-Mean model. In order to make conditional distribution of financial returns skewed we considered the unified approach based on the inverse probability integral transformation. In particular, we applied hidden truncation mechanism, inverse scale factors, order statistics concept, Beta and Bernstein distribution transformations and also a constructive method. Based on the daily excess returns on the Warsaw Stock Exchange Index we checked the empirical importance of the conditional skewness assumption on the relation between risk and return on the Warsaw Stock Market. We present posterior probabilities of all competing specifications as well as the posterior analysis of the positive sign of the tested relationship.

  14. Buffered Clock Tree Sizing for Skew Minimization Under Power and Thermal Budgets Krit Athikulwongse, Xin Zhao, and Sung Kyu Lim

    E-print Network

    Lim, Sung Kyu

    - sipation in synchronous VLSI systems. Low-power clock tree design has become a crucial step in determining- linear fashion due to the wire resistance and capacitance changes. Buffer sizing affects the driving resistance and input capacitance of the buffer, which in turn changes clock skew. This wire/buffer sizing

  15. Genetic variation in nuclear and mitochondrial markers supports a large sex difference in lifetime reproductive skew in a lekking species

    PubMed Central

    Verkuil, Yvonne I; Juillet, Cedric; Lank, David B; Widemo, Fredrik; Piersma, Theunis

    2014-01-01

    Sex differences in skews of vertebrate lifetime reproductive success are difficult to measure directly. Evolutionary histories of differential skew should be detectable in the genome. For example, male-biased skew should reduce variation in the biparentally inherited genome relative to the maternally inherited genome. We tested this approach in lek-breeding ruff (Class Aves, Philomachus pugnax) by comparing genetic variation of nuclear microsatellites (?n; biparental) versus mitochondrial D-loop sequences (?m; maternal), and conversion to comparable nuclear (Ne) and female (Nef) effective population size using published ranges of mutation rates for each marker (?). We provide a Bayesian method to calculate Ne (?n = 4Ne?n) and Nef (?m = 2Nef?m) using 95% credible intervals (CI) of ?n and ?m as informative priors, and accounting for uncertainty in ?. In 96 male ruffs from one population, Ne was 97% (79–100%) lower than expected under random mating in an ideal population, where Ne:Nef = 2. This substantially lower autosomal variation represents the first genomic support of strong male reproductive skew in a lekking species. PMID:25478153

  16. Th1-skewed tissue responses to a mycolyl glycolipid in mycobacteria-infected rhesus macaques

    SciTech Connect

    Morita, Daisuke; Miyamoto, Ayumi; Hattori, Yuki; Komori, Takaya; Nakamura, Takashi; Igarashi, Tatsuhiko; Harashima, Hideyoshi; Sugita, Masahiko

    2013-11-08

    Highlights: •Glucose monomycolate (GMM) is a marker glycolipid for active tuberculosis. •Tissue responses to GMM involved up-regulation of Th1-attracting chemokines. •Th1-skewed local responses were mounted at the GMM-injected tissue. -- Abstract: Trehalose 6,6?-dimycolate (TDM) is a major glycolipid of the cell wall of mycobacteria with remarkable adjuvant functions. To avoid detection by the host innate immune system, invading mycobacteria down-regulate the expression of TDM by utilizing host-derived glucose as a competitive substrate for their mycolyltransferases; however, this enzymatic reaction results in the concomitant biosynthesis of glucose monomycolate (GMM) which is recognized by the acquired immune system. GMM-specific, CD1-restricted T cell responses have been detected in the peripheral blood of infected human subjects and monkeys as well as in secondary lymphoid organs of small animals, such as guinea pigs and human CD1-transgenic mice. Nevertheless, it remains to be determined how tissues respond at the site where GMM is produced. Here we found that rhesus macaques vaccinated with Mycobacterium bovis bacillus Calmette–Guerin mounted a chemokine response in GMM-challenged skin that was favorable for recruiting T helper (Th)1 T cells. Indeed, the expression of interferon-?, but not Th2 or Th17 cytokines, was prominent in the GMM-injected tissue. The GMM-elicited tissue response was also associated with the expression of monocyte/macrophage-attracting CC chemokines, such as CCL2, CCL4 and CCL8. Furthermore, the skin response to GMM involved the up-regulated expression of granulysin and perforin. Given that GMM is produced primarily by pathogenic mycobacteria proliferating within the host, the Th1-skewed tissue response to GMM may function efficiently at the site of infection.

  17. Ultra-High Energy Cosmic Rays: Composition, Early Air Shower Interactions, and Xmax Skewness

    NASA Astrophysics Data System (ADS)

    Stapleton, James

    The composition of Ultra-High Energy Cosmic Rays (UHECRs) is still not completely understood, and must be inferred from Extended Air Shower (EAS), particle cascades which they initiate upon entering the atmosphere. The atmospheric depth at which the shower contains the maximum number of particles ( Xmax) is the most composition-sensitive property of the air shower, but its interpretation is hindered by intrinsic statistical fluctuations in EAS development which cause distinct compositions to produce overlapping Xmax distributions as well as our limited knowledge at these energies of hadronic physics which strongly impacts the Xmax distribution's shape. These issues ultimately necessitate a variety of complementary approaches to interpreting UHECR composition from Xmax data. The current work advances these approaches by connecting X max skewness to the uncertainties above. The study of X max has historically focused only on the mean and standard deviation of its distribution, but skewness is shown here to be strongly related to both the statistical fluctuations in EAS development as well as the least-understood hadronic cross-sections in the air shower. This leads into a treatment of the Exponentially-Modified Gaussian (EMG) distribution, whose little-known properties make it very useful for Xmax analysis and for data analysis in general. A powerful method emerges which uses only descriptive statistics in a robust check for energy-dependent changes in UHECR mass or EAS development. The application of these analyses to X max data provides tantalizing clues concerning issues of critical importance, such as the relationship between Xmax and the 'ankle' break in the UHECR energy spectrum, or the inferred properties of the UHECR mass distribution and its strong dependence on hadronic model systematics.

  18. A missing model in reproductive skew theory: the bordered tug-of-war.

    PubMed

    Reeve, Hudson Kern; Shen, Sheng-Feng

    2006-05-30

    Models of reproductive skew can be classified into two groups: transactional models, in which group members yield shares of reproduction to each other in return for cooperation, and tug-of-war models, in which group members invest group resources in a tug-of-war over their respective reproductive shares. We synthesize these two models to yield a "bordered tug-of-war" model in which the internal tug-of-war is limited ("bordered") by the requirement that group members must achieve a certain amount of reproduction lest they pursue a noncooperative option leading to group breakup. Previous attempts to synthesize these two models did not allow for the fact that the tug-of-war will affect group output, which in turn feeds back on the reproductive payments required by group members to remain cooperative. The bordered tug-of-war model, which does not assume complete reproductive control by any individual and allows for conflict within groups, predicts that the degree of within-group selfishness will increase as the noncooperative options become less attractive, e.g., as ecological constraints on solitary breeding increase. When the noncooperative option involves fighting for the group resource (e.g., territory) and leaving if the fight is lost, the subordinate's overall share of reproduction is predicted to be independent of its relatedness to the dominant and to increase the greater its probability of winning the fight, the less the value of the territory, and the greater its personal payoff for leaving. The unique predictions of the bordered tug-of-war model may fit skew data from a number of species, including meerkats, lions, and wood mice. PMID:16717185

  19. Bayesian WLS/GLS regression for regional skewness analysis for regions with large crest stage gage networks

    USGS Publications Warehouse

    Veilleux, Andrea G.; Stedinger, Jery R.; Eash, David A.

    2012-01-01

    This paper summarizes methodological advances in regional log-space skewness analyses that support flood-frequency analysis with the log Pearson Type III (LP3) distribution. A Bayesian Weighted Least Squares/Generalized Least Squares (B-WLS/B-GLS) methodology that relates observed skewness coefficient estimators to basin characteristics in conjunction with diagnostic statistics represents an extension of the previously developed B-GLS methodology. B-WLS/B-GLS has been shown to be effective in two California studies. B-WLS/B-GLS uses B-WLS to generate stable estimators of model parameters and B-GLS to estimate the precision of those B-WLS regression parameters, as well as the precision of the model. The study described here employs this methodology to develop a regional skewness model for the State of Iowa. To provide cost effective peak-flow data for smaller drainage basins in Iowa, the U.S. Geological Survey operates a large network of crest stage gages (CSGs) that only record flow values above an identified recording threshold (thus producing a censored data record). CSGs are different from continuous-record gages, which record almost all flow values and have been used in previous B-GLS and B-WLS/B-GLS regional skewness studies. The complexity of analyzing a large CSG network is addressed by using the B-WLS/B-GLS framework along with the Expected Moments Algorithm (EMA). Because EMA allows for the censoring of low outliers, as well as the use of estimated interval discharges for missing, censored, and historic data, it complicates the calculations of effective record length (and effective concurrent record length) used to describe the precision of sample estimators because the peak discharges are no longer solely represented by single values. Thus new record length calculations were developed. The regional skewness analysis for the State of Iowa illustrates the value of the new B-WLS/BGLS methodology with these new extensions.

  20. Replacement bridge crossing uses unique pipe rollers

    SciTech Connect

    Cline, R.A.

    1982-03-01

    Spanning the Schuykill River between Valley Forge and Norristown, Pa., the old steel-truss Betzwood Bridge was used by PECO to carry a 12-in. high-pressure main from 1927 until 1981, when a routine inspection disclosed that the west edge of the south abutment had collapsed, leaving only the 12-in. gas main to support the southwest end of the bridge. PECO's engineers installed a new main in the new Betzwood Bridge, located 150 ft downstream from the historic truss structure. They surmounted restrictions against welding or dilling the bridge's structural steel by suspending the pipeline from the bridge crossbeams using insulating pipe rollers, a patented product that electrically isolates the pipe from the bridge structure and protects the coating and pipe from abrasion and wear. The rollers, along with specially forged steel beam clamps, now hold the pipe in its suspended position.

  1. Network Bridging Potential in Later Life

    PubMed Central

    Cornwell, Benjamin

    2009-01-01

    Objectives Much work in social gerontology has examined older adults’ social connectedness, but we know little about the extent to which older adults occupy positions of power and independence in their networks. The author uses health and life-course frameworks to understand older adults’ prospects of occupying bridging positions between otherwise unconnected individuals. Methods Egocentric social network data were collected from a nationally representative sample of 3,005 older adults between the ages of 57 and 85 in 2005–2006. A series of multivariate regression analyses was used to examine how health and life-course factors relate to bridging. Results Age is not significantly associated with bridging. However, retirees and people with poor health are less likely to have bridging potential. At the same time, widows are more likely to serve as bridges. Discussion The discusses the need for more dialogue between social network researchers and social gerontologists to help explain older adults’ bridging prospects. PMID:19144972

  2. Level II scour analysis for Bridge 42 (RANDVT00120042) on State Highway 12, crossing Third Branch White River, Randolph, Vermont

    USGS Publications Warehouse

    Olson, Scott A.; Weber, Matthew A.

    1996-01-01

    bridge consisting of four concrete spans. The maximum span length is 57 ft. (Vermont Agency of Transportation, written commun., July 29, 1994). The bridge is supported by vertical, concrete abutments and three concrete piers. The toe of the left abutment is at the channel edge. The toe of the right abutment is set back on the right over-bank. The roadway centerline on the structure has a slight horizontal curve; however, the main channel is skewed approximately 5 degrees to the bridge. Additional details describing conditions at the site are included in the Level II Summary and Appendices D and E. Scour depths and rock rip-rap sizes were computed using the general guidelines described in Hydraulic Engineering Circular 18 (Richardson and others, 1993). Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. The scour analysis results are presented in tables 1 and 2 and a graph of the scour depths is presented in figure 8.

  3. 75 FR 62181 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-07

    ...britab.htm. FOR FURTHER INFORMATION CONTACT: Ms. Ann Shemaka, Office of Bridge Technology, HIBT-30, (202) 366-1575, or Mr. Thomas Everett, Office of Bridge Technology, HIBT-30, (202) 366-4675, Federal Highway Administration,...

  4. 76 FR 55160 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-06

    ...brdgtabs.cfm. FOR FURTHER INFORMATION CONTACT: Ms. Ann Shemaka, Office of Bridge Technology, HIBT-30, (202) 366-1575, or Mr. Thomas Everett, Office of Bridge Technology, HIBT-30, (202) 366-4675, Federal Highway Administration,...

  5. A data management infrastructure for bridge monitoring

    NASA Astrophysics Data System (ADS)

    Jeong, Seongwoon; Byun, Jaewook; Kim, Daeyoung; Sohn, Hoon; Bae, In Hwan; Law, Kincho H.

    2015-04-01

    This paper discusses a data management infrastructure framework for bridge monitoring applications. As sensor technologies mature and become economically affordable, their deployment for bridge monitoring will continue to grow. Data management becomes a critical issue not only for storing the sensor data but also for integrating with the bridge model to support other functions, such as management, maintenance and inspection. The focus of this study is on the effective data management of bridge information and sensor data, which is crucial to structural health monitoring and life cycle management of bridge structures. We review the state-of-the-art of bridge information modeling and sensor data management, and propose a data management framework for bridge monitoring based on NoSQL database technologies that have been shown useful in handling high volume, time-series data and to flexibly deal with unstructured data schema. Specifically, Apache Cassandra and Mongo DB are deployed for the prototype implementation of the framework. This paper describes the database design for an XML-based Bridge Information Modeling (BrIM) schema, and the representation of sensor data using Sensor Model Language (SensorML). The proposed prototype data management framework is validated using data collected from the Yeongjong Bridge in Incheon, Korea.

  6. 33 CFR 118.90 - Bridges crossing channel obliquely.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Bridges crossing channel... SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.90 Bridges crossing channel obliquely. Bridges crossing a body of water at an angle other than 90° with the axis of the channel shall be lighted...

  7. Willamette River Transit Bridge PSU CTS Seminar January 16, 2009

    E-print Network

    Bertini, Robert L.

    · Trusses and Arches · Cable Supported · Movable #12;Willamette River Transit Bridge Proposed BridgeWillamette River Transit Bridge PSU CTS Seminar January 16, 2009 Dave Unsworth, TriMet Guenevere River Transit Bridge · Portland-Milwaukie Light Rail Project · Plans for a new Willamette River Bridge

  8. MULTI-HAZARD RESISTANT HIGHWAY BRIDGE PIERS HAVING

    E-print Network

    Bruneau, Michel

    of California to its main suspension bridges and the detailed shots of the Golden Gate and Brooklyn bridgesMULTI-HAZARD RESISTANT HIGHWAY BRIDGE PIERS HAVING CONCRETE-FILLED STEEL TUBE Shuichi FUJIKURA1 of a multi-hazard bridge pier concept, i.e., a bridge pier system capable of providing an adequate level

  9. 23 CFR 650.307 - Bridge inspection organization.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 23 Highways 1 2014-04-01 2014-04-01 false Bridge inspection organization. 650.307 Section 650.307... BRIDGES, STRUCTURES, AND HYDRAULICS National Bridge Inspection Standards § 650.307 Bridge inspection... bridges located on public roads that are fully or partially located within the State's boundaries,...

  10. 49 CFR 237.101 - Scheduling of bridge inspections.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Scheduling of bridge inspections. 237.101 Section... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.101 Scheduling of bridge inspections. (a) Each bridge management program shall include a provision for scheduling...

  11. 33 CFR 118.85 - Lights on vertical lift bridges.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on vertical lift bridges... BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.85 Lights on vertical lift bridges. (a) Lift span lights. The vertical lift span of every vertical lift bridge shall be lighted so that the center of...

  12. 49 CFR 237.31 - Adoption of bridge management programs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Adoption of bridge management programs. 237.31... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Railroad Bridge Safety Assurance § 237.31 Adoption of bridge management programs. Each track owner shall adopt a bridge safety management program...

  13. 49 CFR 237.31 - Adoption of bridge management programs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Adoption of bridge management programs. 237.31... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Railroad Bridge Safety Assurance § 237.31 Adoption of bridge management programs. Each track owner shall adopt a bridge safety management program...

  14. 33 CFR 118.85 - Lights on vertical lift bridges.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Lights on vertical lift bridges... BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.85 Lights on vertical lift bridges. (a) Lift span lights. The vertical lift span of every vertical lift bridge shall be lighted so that the center of...

  15. 49 CFR 237.31 - Adoption of bridge management programs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Adoption of bridge management programs. 237.31... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Railroad Bridge Safety Assurance § 237.31 Adoption of bridge management programs. Each track owner shall adopt a bridge safety management program...

  16. 49 CFR 237.107 - Conduct of bridge inspections.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Conduct of bridge inspections. 237.107 Section 237... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.107 Conduct of bridge inspections. Bridge inspections shall be conducted under the direct supervision of a...

  17. 33 CFR 118.85 - Lights on vertical lift bridges.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Lights on vertical lift bridges... BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.85 Lights on vertical lift bridges. (a) Lift span lights. The vertical lift span of every vertical lift bridge shall be lighted so that the center of...

  18. 49 CFR 237.101 - Scheduling of bridge inspections.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Scheduling of bridge inspections. 237.101 Section... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.101 Scheduling of bridge inspections. (a) Each bridge management program shall include a provision for scheduling...

  19. 49 CFR 237.107 - Conduct of bridge inspections.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Conduct of bridge inspections. 237.107 Section 237... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.107 Conduct of bridge inspections. Bridge inspections shall be conducted under the direct supervision of a...

  20. 33 CFR 118.85 - Lights on vertical lift bridges.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Lights on vertical lift bridges... BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.85 Lights on vertical lift bridges. (a) Lift span lights. The vertical lift span of every vertical lift bridge shall be lighted so that the center of...

  1. 49 CFR 237.107 - Conduct of bridge inspections.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Conduct of bridge inspections. 237.107 Section 237... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.107 Conduct of bridge inspections. Bridge inspections shall be conducted under the direct supervision of a...

  2. 49 CFR 237.101 - Scheduling of bridge inspections.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Scheduling of bridge inspections. 237.101 Section... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.101 Scheduling of bridge inspections. (a) Each bridge management program shall include a provision for scheduling...

  3. 33 CFR 118.85 - Lights on vertical lift bridges.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Lights on vertical lift bridges... BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.85 Lights on vertical lift bridges. (a) Lift span lights. The vertical lift span of every vertical lift bridge shall be lighted so that the center of...

  4. 49 CFR 237.107 - Conduct of bridge inspections.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Conduct of bridge inspections. 237.107 Section 237... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.107 Conduct of bridge inspections. Bridge inspections shall be conducted under the direct supervision of a...

  5. 23 CFR 650.307 - Bridge inspection organization.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Bridge inspection organization. 650.307 Section 650.307... BRIDGES, STRUCTURES, AND HYDRAULICS National Bridge Inspection Standards § 650.307 Bridge inspection... bridges located on public roads that are fully or partially located within the State's boundaries,...

  6. 49 CFR 237.31 - Adoption of bridge management programs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Adoption of bridge management programs. 237.31... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Railroad Bridge Safety Assurance § 237.31 Adoption of bridge management programs. Each track owner shall adopt a bridge safety management program...

  7. 49 CFR 237.101 - Scheduling of bridge inspections.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Scheduling of bridge inspections. 237.101 Section... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.101 Scheduling of bridge inspections. (a) Each bridge management program shall include a provision for scheduling...

  8. 49 CFR 237.31 - Adoption of bridge management programs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Adoption of bridge management programs. 237.31... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Railroad Bridge Safety Assurance § 237.31 Adoption of bridge management programs. Each track owner shall adopt a bridge safety management program...

  9. 23 CFR 650.307 - Bridge inspection organization.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 23 Highways 1 2011-04-01 2011-04-01 false Bridge inspection organization. 650.307 Section 650.307... BRIDGES, STRUCTURES, AND HYDRAULICS National Bridge Inspection Standards § 650.307 Bridge inspection... bridges located on public roads that are fully or partially located within the State's boundaries,...

  10. 49 CFR 237.101 - Scheduling of bridge inspections.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Scheduling of bridge inspections. 237.101 Section... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.101 Scheduling of bridge inspections. (a) Each bridge management program shall include a provision for scheduling...

  11. 23 CFR 650.307 - Bridge inspection organization.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 23 Highways 1 2012-04-01 2012-04-01 false Bridge inspection organization. 650.307 Section 650.307... BRIDGES, STRUCTURES, AND HYDRAULICS National Bridge Inspection Standards § 650.307 Bridge inspection... bridges located on public roads that are fully or partially located within the State's boundaries,...

  12. 49 CFR 237.107 - Conduct of bridge inspections.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Conduct of bridge inspections. 237.107 Section 237... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.107 Conduct of bridge inspections. Bridge inspections shall be conducted under the direct supervision of a...

  13. 23 CFR 650.307 - Bridge inspection organization.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 23 Highways 1 2013-04-01 2013-04-01 false Bridge inspection organization. 650.307 Section 650.307... BRIDGES, STRUCTURES, AND HYDRAULICS National Bridge Inspection Standards § 650.307 Bridge inspection... bridges located on public roads that are fully or partially located within the State's boundaries,...

  14. 49 CFR 237.103 - Bridge inspection procedures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Bridge inspection procedures. 237.103 Section 237... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.103 Bridge inspection procedures. (a) Each bridge management program shall specify the procedure to be used...

  15. 49 CFR 237.103 - Bridge inspection procedures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Bridge inspection procedures. 237.103 Section 237... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.103 Bridge inspection procedures. (a) Each bridge management program shall specify the procedure to be used...

  16. 49 CFR 237.71 - Determination of bridge load capacities.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... from existing design and modification records of a bridge, provided that the bridge substantially... 49 Transportation 4 2014-10-01 2014-10-01 false Determination of bridge load capacities. 237.71... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Capacity of Bridges § 237.71...

  17. Empirical Study of Life-Cycle Cost Analysis for Bridges

    E-print Network

    for bridge life-cycle cost · Determine the design practice that leads to the lowest bridge life-cycle costEmpirical Study of Life-Cycle Cost Analysis for Bridges Progress Report Ahmad Hadavi, PhD, PE and their timing during the life of a bridge to achieve the 50- to 100-year service life that many bridge

  18. 49 CFR 237.71 - Determination of bridge load capacities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... from existing design and modification records of a bridge, provided that the bridge substantially... 49 Transportation 4 2012-10-01 2012-10-01 false Determination of bridge load capacities. 237.71... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Capacity of Bridges § 237.71...

  19. 49 CFR 237.71 - Determination of bridge load capacities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... from existing design and modification records of a bridge, provided that the bridge substantially... 49 Transportation 4 2011-10-01 2011-10-01 false Determination of bridge load capacities. 237.71... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Capacity of Bridges § 237.71...

  20. 49 CFR 237.103 - Bridge inspection procedures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Bridge inspection procedures. 237.103 Section 237... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.103 Bridge inspection procedures. (a) Each bridge management program shall specify the procedure to be used...

  1. IN-SERVICE LOAD & RESISTANCE FACTOR RATING METHOD FOR BRIDGES

    E-print Network

    Bhattacharya, Baidurya

    is different from bridge design. When bridges are designed, the behavior of the as-built bridge, as well as the nature of the site-specific traffic, can only be estimated. Bridge design is by necessity conservativeIN-SERVICE LOAD & RESISTANCE FACTOR RATING METHOD FOR BRIDGES Degang Li1 , Baidurya Bhattacharya2

  2. 49 CFR 237.103 - Bridge inspection procedures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Bridge inspection procedures. 237.103 Section 237... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.103 Bridge inspection procedures. (a) Each bridge management program shall specify the procedure to be used...

  3. 49 CFR 237.103 - Bridge inspection procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Bridge inspection procedures. 237.103 Section 237... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.103 Bridge inspection procedures. (a) Each bridge management program shall specify the procedure to be used...

  4. 49 CFR 237.71 - Determination of bridge load capacities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... from existing design and modification records of a bridge, provided that the bridge substantially... 49 Transportation 4 2010-10-01 2010-10-01 false Determination of bridge load capacities. 237.71... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Capacity of Bridges § 237.71...

  5. 49 CFR 237.71 - Determination of bridge load capacities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... from existing design and modification records of a bridge, provided that the bridge substantially... 49 Transportation 4 2013-10-01 2013-10-01 false Determination of bridge load capacities. 237.71... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Capacity of Bridges § 237.71...

  6. 49 CFR 236.312 - Movable bridge, interlocking of signal appliances with bridge devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Movable bridge, interlocking of signal appliances with bridge devices. 236.312 Section 236.312 Transportation Other Regulations Relating to... SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.312 Movable bridge, interlocking of...

  7. 49 CFR 236.312 - Movable bridge, interlocking of signal appliances with bridge devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Movable bridge, interlocking of signal appliances with bridge devices. 236.312 Section 236.312 Transportation Other Regulations Relating to... SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.312 Movable bridge, interlocking of...

  8. 49 CFR 236.312 - Movable bridge, interlocking of signal appliances with bridge devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Movable bridge, interlocking of signal appliances with bridge devices. 236.312 Section 236.312 Transportation Other Regulations Relating to... SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.312 Movable bridge, interlocking of...

  9. 49 CFR 236.312 - Movable bridge, interlocking of signal appliances with bridge devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Movable bridge, interlocking of signal appliances with bridge devices. 236.312 Section 236.312 Transportation Other Regulations Relating to... SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.312 Movable bridge, interlocking of...

  10. 49 CFR 236.312 - Movable bridge, interlocking of signal appliances with bridge devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Movable bridge, interlocking of signal appliances with bridge devices. 236.312 Section 236.312 Transportation Other Regulations Relating to... SYSTEMS, DEVICES, AND APPLIANCES Interlocking Standards § 236.312 Movable bridge, interlocking of...

  11. The Pennsylvania State University www.BioEnergyBridge.psu.edu 1 BioEnergy Bridge

    E-print Network

    Lee, Dongwon

    © The Pennsylvania State University www.BioEnergyBridge.psu.edu 1 Penn State BioEnergy Bridge Partnership The Pennsylvania State University Bob Wallace, Director TM #12;© The Pennsylvania State University www.BioEnergyBridge.psu.edu 2 · Penn State Institutes of Energy

  12. 77 FR 53251 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-31

    ...bridge/brdgtabs.cfm. FOR FURTHER INFORMATION CONTACT: Ms. Ann Shemaka, Office of Bridge Technology, (202) 366-1575, or via email at ann.shemaka@dot.gov or Mr. Thomas Everett, Office of Bridge Technology, (202) 366-4675, or...

  13. 6. VIEW OF GDOT BRIDGE NO. 02700268X00678N BRIDGE PLATE IDENTIFYING ...

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

    6. VIEW OF GDOT BRIDGE NO. 027-00268X-00678N BRIDGE PLATE IDENTIFYING COUNTY COMMISSIONERS AT THE TIME OF CONSTRUCTION. - GDOT Bridge No. 027-00268X-00678N, County Road 268-Empress Road span Piscola Creek, Quitman, Brooks County, GA

  14. Bridge-Mediated Two-Electron Transfer via Delocalized Bridge Orbitals E. G. Petrov, Ya. R. Zelinskyy, and V. May*,

    E-print Network

    Röder, Beate

    Bridge-Mediated Two-Electron Transfer via Delocalized Bridge Orbitals E. G. Petrov, Ya. R, 2004 Bridge mediated two-electron transfer (TET) in a donor-acceptor (D-A) complex is studied theoretically. A type of bridge is considered where the intersite coupling in the bridge becomes so large

  15. Bridge Scour Measurements Using the Rfid Technology

    NASA Astrophysics Data System (ADS)

    Moustakidis, I.; Tsakiris, A. G.; Papanicolaou, T.

    2010-12-01

    The main purpose of this project is to develop a system for continuous monitoring scour around bridge piers and abutments (i.e. bridge scour) using the Radio Frequency IDentification (RFID) technology and examine its applicability for estimating scour around a pier or an existing bridge. Excessive bridge scour can compromise the bridge foundations and lead to dramatic bridge collapses with significant impacts on economy and traveling public safety. An RFID system consists of three main components: the low frequency reader (~134.2 kHz frequency), the transponder (derived from transmitter/responder) and the antenna (of rectangular shape with one or more loops). RFID is a technology that permits the wireless two-way transfer of information from a reader to a transponder via RF waves transmitted with an antenna. What makes RFIDs suitable for monitoring bridge scour is that no line of sight is necessary between the reader and the transponder, which can be detected even when it is buried in the bed substrate. The proposed system for monitoring bridge scour relies on the principle that transponders oriented perpendicular to antenna plane can be detected at longer distances, than transponders oriented parallel to it. We intend to attach transponders at predetermined locations (depths) along a chain with known length. The chain will subsequently be driven into the bed substrate at the location where bridge scour hole is expected within the detection range of the antenna, which will be installed directly above the chain. The chain will retain the transponders perpendicular to the antenna plane, so that they can be continuously detected. Once scour takes place, the transponders will be oriented parallel to the antenna plane and thus they will not be detected. The latter will indicate that bridge scour reached the known depth, at which the transponder was initially buried. Once a prototype RFID system is functional, future research will aim at combining it with satellite technology for real time acquisition of bridge scour information to a base station.

  16. Bridges to sustainable tropical health

    PubMed Central

    Singer, Burton H.; de Castro, Marcia Caldas

    2007-01-01

    Ensuring sustainable health in the tropics will require bridge building between communities that currently have a limited track record of interaction. It will also require new organizational innovation if much of the negative health consequences of large-scale economic development projects are to be equitably mitigated, if not prevented. We focus attention on three specific contexts: (i) forging linkages between the engineering and health communities to implement clean water and sanitation on a broad scale to prevent reworming, after the current deworming-only programs, of people by diverse intestinal parasites; (ii) building integrated human and animal disease surveillance infrastructure and technical capacity in tropical countries on the reporting and scientific evidence requirements of the sanitary and phytosanitary agreement under the World Trade Organization; and (iii) developing an independent and equitable organizational structure for health impact assessments as well as monitoring and mitigation of health consequences of economic development projects. Effective global disease surveillance and timely early warning of new outbreaks will require a far closer integration of veterinary and human medicine than heretofore. Many of the necessary surveillance components exist within separate animal- and human-oriented organizations. The challenge is to build the necessary bridges between them. PMID:17913894

  17. Capacitance bridge measurements of magnetostriction

    NASA Astrophysics Data System (ADS)

    Boley, Mark S.; Shin, Won C.; Rigsbee, David K.; Franklin, Doug A.

    2002-05-01

    Magnetostriction effects were investigated for three different materials by using a simple, reproducible, and cost-effective method recently developed in our laboratory. The magnetostriction effects were generated by a large oscillating magnetic field produced by a high current 60 Hz ac welder power supply, capable of reaching saturation levels for the material, and then detected by a change in capacitance between a hollow cylindrical sample and a concentric brass ring. This capacitance change was continuously monitored at a high frequency rate by a standard laboratory capacitance bridge meter. The output voltage of the bridge was fed into a storage cathode-ray oscilloscope and its voltage versus time signals were then analyzed by a computer program. Two ferromagnetic rings, constructed of high-speed steels 4620 and 4340, which have proven applicability for use in magnetoelastic torque sensing, were used as the samples for investigating the magnetostriction effects, while a paramagnetic aluminum ring was used for the control sample. Our study showed that the 4340 ring, which had higher nickel, cobalt, and chromium content than that of the 4620 ring, had the largest magnetostriction effect, and that the aluminum ring displayed no magnetostriction effect, as was expected. We have found this experimental method to be both reproducible and sufficient to rank different ferromagnetic materials by their magnetostriction level, which is a significant consideration in producing effective magnetoelastic torque sensors.

  18. Global monitoring concept for bridges

    NASA Astrophysics Data System (ADS)

    Bergmeister, Konrad; Santa, Ulrich

    2000-06-01

    Knowledge of the integrity of in-service structures on a continuous time basis is an ultimate objective for owners and maintenance authorities. The development of a life extension and/or replacement strategy for highway structures is a crucial point in an effective bridge management system. A key component of such a bridge management system is a means of surveillance techniques and determining the condition of an existing structure within the normative and budgetary constraints. Recent advances in sensing technologies and material/structure damage characterization combined with current developments in computations and communications have resulted in a significant interest in developing diagnostic technologies for monitoring the integrity of and for the detection of damages of structures. To identify anomalies and deterioration processes, it is essential to understand the relationships between the signal measurements and the real occurred phenomena. Therefore, the comparison of measured and calculated data in order to tune and validate the mechanical and numerical model assumptions is an integral part of any system analysis. Finally, the interpreted results of all measurements should be the basis for the condition assessment and the safety evaluation of a structure to facilitate replacement and repair decisions.

  19. NPIP: A skew line needle configuration optimization system for HDR brachytherapy

    SciTech Connect

    Siauw, Timmy; Cunha, Adam; Berenson, Dmitry; Atamtuerk, Alper; Hsu, I-Chow; Goldberg, Ken; Pouliot, Jean

    2012-07-15

    Purpose: In this study, the authors introduce skew line needle configurations for high dose rate (HDR) brachytherapy and needle planning by integer program (NPIP), a computational method for generating these configurations. NPIP generates needle configurations that are specific to the anatomy of the patient, avoid critical structures near the penile bulb and other healthy structures, and avoid needle collisions inside the body. Methods: NPIP consisted of three major components: a method for generating a set of candidate needles, a needle selection component that chose a candidate needle subset to be inserted, and a dose planner for verifying that the final needle configuration could meet dose objectives. NPIP was used to compute needle configurations for prostate cancer data sets from patients previously treated at our clinic. NPIP took two user-parameters: a number of candidate needles, and needle coverage radius, {delta}. The candidate needle set consisted of 5000 needles, and a range of {delta} values was used to compute different needle configurations for each patient. Dose plans were computed for each needle configuration. The number of needles generated and dosimetry were analyzed and compared to the physician implant. Results: NPIP computed at least one needle configuration for every patient that met dose objectives, avoided healthy structures and needle collisions, and used as many or fewer needles than standard practice. These needle configurations corresponded to a narrow range of {delta} values, which could be used as default values if this system is used in practice. The average end-to-end runtime for this implementation of NPIP was 286 s, but there was a wide variation from case to case. Conclusions: The authors have shown that NPIP can automatically generate skew line needle configurations with the aforementioned properties, and that given the correct input parameters, NPIP can generate needle configurations which meet dose objectives and use as many or fewer needles than the current HDR brachytherapy workflow. Combined with robot assisted brachytherapy, this system has the potential to reduce side effects associated with treatment. A physical trial should be done to test the implant feasibility of NPIP needle configurations.

  20. Politicizing NIH funding: a bridge to nowhere.

    PubMed

    Epstein, Jonathan A

    2011-09-01

    We live in a time of increased spending, mounting debt, and few remedies for balancing the federal budget that have bipartisan support. Unfortunately, one recent target for decreased allocations of the federal budget is the NIH; the discussion of the awarded grants and the grant funding process has been skewed and altered to present medical research in an unfriendly light, and this can have very damaging repercussions. Politicizing this process could ultimately challenge human health, technology, and economic growth. PMID:21881213

  1. 1. AERIAL VIEW OF THE PATH TRANSIT SYSTEM BRIDGE, LOOKING ...

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

    1. AERIAL VIEW OF THE PATH TRANSIT SYSTEM BRIDGE, LOOKING NORTHEAST. THE CONRAIL BRIDGE (HAER No. NJ-43) AND THE NEWARK TURNPIKE ARE VISIBLE IN THE BACKGROUND - Path Transit System Bridge, Spanning Hackensack River, Kearny, Hudson County, NJ

  2. 46 CFR 112.43-7 - Navigating bridge distribution panel.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... false Navigating bridge distribution panel. 112.43-7 Section 112.43-7...43-7 Navigating bridge distribution panel. (a) Except as allowed in paragraph...lights must be supplied from a distribution panel on the navigating bridge: (1)...

  3. 46 CFR 112.43-7 - Navigating bridge distribution panel.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... false Navigating bridge distribution panel. 112.43-7 Section 112.43-7...43-7 Navigating bridge distribution panel. (a) Except as allowed in paragraph...lights must be supplied from a distribution panel on the navigating bridge: (1)...

  4. 46 CFR 112.43-7 - Navigating bridge distribution panel.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... false Navigating bridge distribution panel. 112.43-7 Section 112.43-7...43-7 Navigating bridge distribution panel. (a) Except as allowed in paragraph...lights must be supplied from a distribution panel on the navigating bridge: (1)...

  5. 46 CFR 112.43-7 - Navigating bridge distribution panel.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... false Navigating bridge distribution panel. 112.43-7 Section 112.43-7...43-7 Navigating bridge distribution panel. (a) Except as allowed in paragraph...lights must be supplied from a distribution panel on the navigating bridge: (1)...

  6. 46 CFR 112.43-7 - Navigating bridge distribution panel.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... false Navigating bridge distribution panel. 112.43-7 Section 112.43-7...43-7 Navigating bridge distribution panel. (a) Except as allowed in paragraph...lights must be supplied from a distribution panel on the navigating bridge: (1)...

  7. 1. Contextual view of bridge in setting, from downstream, view ...

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

    1. Contextual view of bridge in setting, from downstream, view to southwest along Port Kenyon Road. South end of bridge at left. - Salt River Bridge, Spanning Salt River at Dillon Road, Ferndale, Humboldt County, CA

  8. 2. Contextual view of bridge in setting, from north end ...

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

    2. Contextual view of bridge in setting, from north end of bridge, view to north along Dillon Road. Former Valley Flower Creamery at right center. - Salt River Bridge, Spanning Salt River at Dillon Road, Ferndale, Humboldt County, CA

  9. 1. Photocopy of photograph, 1972. GRAFTON BRIDGE. (Taken from 'American ...

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

    1. Photocopy of photograph, 1972. GRAFTON BRIDGE. (Taken from 'American Railroad Bridges,' Trans, A.S.C.E., Theodore Cooper, 1889) - Northwestern Virginia Railroad, Grafton Bridge, Spanning Tygart Valley River, Grafton, Taylor County, WV

  10. 7. Photocopy of photograph, 1972. GRAFTON BRIDGE (From 'American Railroad ...

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

    7. Photocopy of photograph, 1972. GRAFTON BRIDGE (From 'American Railroad Bridges,' Trans. A.S.C.E., Theodore Cooper, 1889) - Northwestern Virginia Railroad, Grafton Bridge, Spanning Tygart Valley River, Grafton, Taylor County, WV

  11. 7. VIEW ACROSS BRIDGE FROM NORTHWEST CORNER WITH WIDE ANGLE ...

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

    7. VIEW ACROSS BRIDGE FROM NORTHWEST CORNER WITH WIDE ANGLE LENS SHOWING BRIDGE IN LANDSCAPE. - Wildcat Creek Bridge, Spanning Wildcat Creek on New Big Oak Flat Road, Yosemite Village, Mariposa County, CA

  12. 8. VIEW OF BRIDGE, LOOKING DIRECTLY WEST THROUGH TRUSS FROM ...

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

    8. VIEW OF BRIDGE, LOOKING DIRECTLY WEST THROUGH TRUSS FROM MIDDLE OF BRIDGE - Shenandoah River Bridge, Spanning North fork of Shenandoah River on Virginia State Route 767, Quicksburg, Shenandoah County, VA

  13. 2. VIEW SHOWING SOUTH SIDE OF BRIDGE, LOOKING NORTH, DOWNSTREAM, ...

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

    2. VIEW SHOWING SOUTH SIDE OF BRIDGE, LOOKING NORTH, DOWNSTREAM, FROM DRY PORTION OF RIVER BED, SOUTH OF BRIDGE - Shenandoah River Bridge, Spanning North fork of Shenandoah River on Virginia State Route 767, Quicksburg, Shenandoah County, VA

  14. 19. COPY OF ENGRAVING OF 'WROUGHT IRON ARCH TRUSS BRIDGE,' ...

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

    19. COPY OF ENGRAVING OF 'WROUGHT IRON ARCH TRUSS BRIDGE,' PAT. DEC. 10, 1867 BY OHIO BRIDGE COMPANY, CLEVELAND, OHIO. (COURTESY OF OHIO HISTORICAL SOCIETY ARCHIVES, COLUMBUS, OHIO) - Tioronda Bridge, South Avenue spanning Fishkill Creek, Beacon, Dutchess County, NY

  15. 1. OVERALL VIEW OF BRIDGE AND LINCOLN HIGHWAY, SHOWING NORTH ...

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

    1. OVERALL VIEW OF BRIDGE AND LINCOLN HIGHWAY, SHOWING NORTH APPROACH TO BRIDGE. VIEW TO SOUTH. - Rock Valley Bridge, Spanning North Timber Creek at Old U.S. Highway 30, Marshalltown, Marshall County, IA

  16. 3. VIEW EAST TOWARD STAMFORD ANCHOR BRIDGE #374 OF CIRCUIT ...

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

    3. VIEW EAST TOWARD STAMFORD ANCHOR BRIDGE #374 OF CIRCUIT BREAKER INSTALLATION ON CROSS BEAM OF BRIDGE. - New York, New Haven & Hartford Railroad, Bridge-Type Circuit Breakers, Long Island shoreline between Stamford & New Haven, Cos Cob, Fairfield County, CT

  17. 2. VIEW EAST TOWARD DARIEN ANCHOR BRIDGE #465 OF CIRCUIT ...

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

    2. VIEW EAST TOWARD DARIEN ANCHOR BRIDGE #465 OF CIRCUIT BREAKER INSTALLATION ON CROSS BEAM OF BRIDGE. - New York, New Haven & Hartford Railroad, Bridge-Type Circuit Breakers, Long Island shoreline between Stamford & New Haven, Cos Cob, Fairfield County, CT

  18. ADDITIVITY PROPERTIES OF GENERALIZED BRIDGE NUMBERS OF KNOTS

    E-print Network

    . Later, Helmut Doll generalized the the notion of bridge number of a knot. Schubert's notion of bridge splitting of S 3 , whereas Doll's more general notion of bridge number can be formulated in terms of a nice

  19. 11. Standing on westerly fender at edge of bridge looking ...

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

    11. Standing on westerly fender at edge of bridge looking easterly, showing horizontal beams for deck and cross beams (reflection of steel grating on deck). Also shows bridge guardrail. - Colusa Bridge, Spanning Sacramento River, Colusa, Colusa County, CA

  20. 1. VIEW ACROSS WARREN TRUSS BRIDGE LOOKING EASTERLY FROM WEST ...

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

    1. VIEW ACROSS WARREN TRUSS BRIDGE LOOKING EASTERLY FROM WEST STONE ABUTMENT. THE STEEL FENCE PROHIBITS ACCESS ACROSS BRIDGE. - Double Intersection Warren Truss Bridge, Spanning Blackledge River, Colchester, New London County, CT

  1. 29. Historic photographer, photographer unknown, c. 1944. VIEW OF BRIDGE, ...

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

    29. Historic photographer, photographer unknown, c. 1944. VIEW OF BRIDGE, LOOKING EAST FROM TOP OF WEST TOWER. SHEEP CROSSING BRIDGE. NOTE SWAY CABLES. - Verde River Sheep Bridge, Spanning Verde River (Tonto National Forest), Cave Creek, Maricopa County, AZ

  2. 2. Contextual view of bridge in setting, from northwest end ...

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

    2. Contextual view of bridge in setting, from northwest end of bridge, view to south-southeast with Rawson Road in foreground. - Red Bank Creek Bridge, Spanning Red Bank Creek at Rawson Road, Red Bluff, Tehama County, CA

  3. 27. View of underside of ninth bridge, showing concrete mixture, ...

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

    27. View of underside of ninth bridge, showing concrete mixture, view to the NW. - Vicksburg National Military Park Roads & Bridges, Melan Arch Bridges, Spanning various tributaries at Confederate Avenue, Vicksburg, Warren County, MS

  4. 10. Detail of bridge underside showing gears for locking mechanism ...

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

    10. Detail of bridge underside showing gears for locking mechanism at south end of bridge. View to east. - Locke Avenue Bridge, Locke Avenue (County Route 671) Spanning Raccoon Creek, Swedesboro, Gloucester County, NJ

  5. 21. c, 1915 Historic plan, standard 2 beam girder bridge. ...

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

    21. c, 1915 Historic plan, standard 2 beam girder bridge. United Construction Company, Albany, New York. Generic plan typical of Prescott Bridge. Source: New Hampshire Department of Transportation - Prescott Bridge, Spanning Lamprey River on Prescott Road, Raymond, Rockingham County, NH

  6. 11. View of bridge seat north abutment with expansion bearing, ...

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

    11. View of bridge seat north abutment with expansion bearing, northeast corner of bridge, looking from the east - Bridge No. 4900, Spanning Root River at Trunk Highway 16, Rushford, Fillmore County, MN

  7. STEEL ERECTION. View of upstream side of bridge, looking north ...

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

    STEEL ERECTION. View of upstream side of bridge, looking north from the old suspension bridge at unjoined cantilever arms - South Fork Trinity River Bridge, State Highway 299 spanning South Fork Trinity River, Salyer, Trinity County, CA

  8. 8. West side of north end of bridge resting on ...

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

    8. West side of north end of bridge resting on approach abutment. Oblique detail view northeast (from below roadbed level, beside bridge). 150 mm lens. - Gault Bridge, Spanning Deer Creek at South Pine Street, Nevada City, Nevada County, CA

  9. 1. AERIAL VIEW LOOKING SOUTHWEST (OLD HARVARD STREET BRIDGE AT ...

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

    1. AERIAL VIEW LOOKING SOUTHWEST (OLD HARVARD STREET BRIDGE AT LEFT, NEW BRIDGE AT RIGHT) - Old Harvard Street Bridge, Spanning Rock Creek at National Zoological Park, Washington, District of Columbia, DC

  10. APPROACH VIADUCTS TO TRIBOROUGH SUSPENSION BRIDGE (AT RIGHT), AND THE ...

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

    APPROACH VIADUCTS TO TRIBOROUGH SUSPENSION BRIDGE (AT RIGHT), AND THE HELL GATE BRIDGE (AT LEFT), OVER RANDALL'S ISLAND. - Triborough Bridge, Passing through Queens, Manhattan & the Bronx, Queens (subdivision), Queens County, NY

  11. 33 CFR 115.70 - Advance approval of bridges.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...; and 49 CFR 1.46(c)) ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Advance approval of bridges. 115... BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE PROCEDURES § 115.70 Advance approval of...

  12. 33 CFR 115.70 - Advance approval of bridges.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...; and 49 CFR 1.46(c)) ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Advance approval of bridges. 115... BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE PROCEDURES § 115.70 Advance approval of...

  13. 1. Photocopy from George S. Morison's The Blair Crossing Bridge, ...

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

    1. Photocopy from George S. Morison's The Blair Crossing Bridge, 1886. Photographer unknown, circa 1883. SOUTH WEB AND WEST PORTAL OF BRIDGE - Blair Crossing Bridge, Spanning Missouri River, Blair, Washington County, NE

  14. 21 CFR 872.3770 - Temporary crown and bridge resin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a material, such as polymethylmethacrylate...prosthesis, such as a crown or bridge, for use until a...

  15. 49 CFR 237.103 - Bridge inspection procedures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...the configuration of the bridge; conditions found during...railroad traffic moved over the bridge (including equipment weights...of passenger and hazardous materials traffic); and vulnerability of the bridge to damage. (d) The...

  16. 21 CFR 872.3770 - Temporary crown and bridge resin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a material, such as polymethylmethacrylate...prosthesis, such as a crown or bridge, for use until a...

  17. 49 CFR 237.103 - Bridge inspection procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...the configuration of the bridge; conditions found during...railroad traffic moved over the bridge (including equipment weights...of passenger and hazardous materials traffic); and vulnerability of the bridge to damage. (d) The...

  18. Accurate resistive bridge fault modeling, simulation, and test generation 

    E-print Network

    Sar-Dessai, Vijay Ramesh

    1999-01-01

    Resistive bridging faults in CMOS combinational circuits are studied in this work. Bridging faults are modeled using HSPICE circuit simulation of the various types of bridging faults that can occur in CMOS combinational circuits. The results...

  19. 6. EARLY MORNING VIEW OF BOTH JOSO HIGH BRIDGE (UNION ...

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

    6. EARLY MORNING VIEW OF BOTH JOSO HIGH BRIDGE (UNION PACIFIC RAILROAD) IN BACKGROUND AND LYONS FERRY BRIDGE IN THE FOREGROUND - Snake River Bridge at Lyons' Ferry, State Route 261 spanning Snake River, Starbuck, Columbia County, WA

  20. 5. View showing Crooked River High Bridge in background and ...

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

    5. View showing Crooked River High Bridge in background and Ralph Modjeski railroad bridge in foreground - Crooked River High Bridge, Spanning Crooked River Gorge at Dalles-California Highway, Terrebonne, Deschutes County, OR

  1. 31. TACOMA NARROWS BRIDGE, LOOKING WEST ACROSS TOLL PLAZA, 29 ...

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

    31. TACOMA NARROWS BRIDGE, LOOKING WEST ACROSS TOLL PLAZA, 29 AUGUST 1940. (ELDRIDGE, CLARK M. TACOMA NARROWS BRIDGE, TACOMA, WASHINGTON, FINAL REPORT ON DESIGN AND CONSTRUCTION, 1941) - Tacoma Narrows Bridge, Spanning Narrows at State Route 16, Tacoma, Pierce County, WA

  2. Aeroelastic Analysis of Bridges: Effects of Turbulence and Aerodynamic Nonlinearities

    E-print Network

    Kareem, Ahsan

    , analyti- cal approaches have been widely used in the design of many bridges. Conventional analyticalAeroelastic Analysis of Bridges: Effects of Turbulence and Aerodynamic Nonlinearities Xinzhong Chen for capturing the emerging concerns in bridge aerodynamics introduced by aerodynamic nonlinearities

  3. 30. TACOMA NARROWS BRIDGE, LOOKING EAST THROUGH TOLL LANES, 29 ...

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

    30. TACOMA NARROWS BRIDGE, LOOKING EAST THROUGH TOLL LANES, 29 AUGUST 1940. (ELDRIDGE, CLARK H. TACOMA NARROWS BRIDGE, TACOMA, WASHINGTON, FINAL REPORT ON DESIGN AND CONSTRUCTION, 1941) - Tacoma Narrows Bridge, Spanning Narrows at State Route 16, Tacoma, Pierce County, WA

  4. 12. Interior detail of bridge operator's house showing generator and ...

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

    12. Interior detail of bridge operator's house showing generator and bridge operator, Mr. Gene Amonette, facing west. - Palm Valley Bridge, County Road 210 spanning Intracoastal Waterway, Ponte Vedra Beach, St. Johns County, FL

  5. DUAL FULL-BRIDGE MOTOR DRIVER

    E-print Network

    Wedeward, Kevin

    2998 DUAL FULL-BRIDGE MOTOR DRIVER As an interface between low-level logic and solenoids, dc (brush) motors, or stepper motors, the UDN2998W dual full-bridge driver will operate inductive loads up to 50 V, the two drivers in each package are completely independent. For external PWM control, an Output Enable

  6. A Data Management Infrastructure for Bridge Monitoring

    E-print Network

    Stanford University

    is on the effective data management of bridge information and sensor data, which is crucial to structural health of hundreds and thousands of sensors to collect valuable information about the state of the bridge structure.edu; phone 1 650 666-5556; #12;support Integrated Project Delivery process through exchange of information

  7. Instrumented monitoring of the Commodore Barry Bridge

    NASA Astrophysics Data System (ADS)

    Barrish, Raymond A., Jr.; Grimmelsman, Kirk A.; Aktan, A. Emin

    2000-06-01

    The Drexel Intelligent Infrastructure and Transportation Safety Institute, working in partnership with the Delaware River Port Authority (DRPA), has been investigating the application of various health monitoring techniques to long span bridges. Specifically, the researchers efforts have focused on the Commodore Barry Bridge, a major cantilevered through truss bridge owned by the DRPA. Health monitoring, in the case of civil infrastructure systems, may be considered as measuring and tracking the operating and loading environment of a structure and corresponding structural responses in order to detect and evaluate operational anomalies and deterioration or damage that may impact service or safety reliability. This paper describes the development and implementation of the health monitoring system that has been installed on the Commodore Barry Bridge. Issues that should be considered when conducting health monitoring of long span bridges are also discussed. The health monitoring system takes advantage of in excess of 100 data channels to continuously track the loading environment and numerous structural responses of the bridge. The major attributes of the health monitoring system for this bridge, many of which are applicable for use on other long span bridges, are also presented and described.

  8. Construction of CCC resistance ratio bridge

    SciTech Connect

    Hu, Z.; Jensen, D.H.; Holtoug, J.U.

    1994-12-31

    The paper introduces the cryogenic current comparator (CCC) resistance ratio bridge being built at DFM, which is designed to relate the value of quantized hall resistance R{sub H}(i) to room temperature resistance standards. The CCC is an overlapping tube type with copper wire. A double constant current source is used to supply for the CCC resistance ratio bridge.

  9. BUSINESS ANALYST: A BRIDGE Information Technology

    E-print Network

    Kundu, Sukhamay

    -scheduler of managers in a large company. #12;70.3 BA PROCESS · Understanding business need - The business environmentBUSINESS ANALYST: A BRIDGE BUSINESS ANALYST Information Technology People/Group (functional requirement) Business side of an Enterprise (business needs) · BA forms a bridge, a liaison, between business

  10. Passing the Einstein-Rosen bridge

    E-print Network

    M. O. Katanaev

    2013-10-28

    We relax the requirement of geodesic completeness of a space-time. Instead, we require test particles trajectories to be smooth only in the physical sector. Test particles trajectories for Einstein--Rosen bridge are proved to be smooth in the physical sector, and particles can freely penetrate the bridge in both directions.

  11. Chords Bridge By: Matt Lamon, Yve Kay,

    E-print Network

    Prevedouros, Panos D.

    at the base of Chords Bridge. · Construction Costs were double the original budget. · Total project is runningChords Bridge CEE 491 By: Matt Lamon, Yve Kay, Jared Kim #12;Infrastructure · Designer: ­ Santiago Calatrava · Location: ­ Jerusalem, Israel · Construction Time: ­ Construction began in 2002

  12. Engaging Faculty for Innovative STEM Bridge Programs

    ERIC Educational Resources Information Center

    Goldfien, Andrea C.; Badway, Norena Norton

    2014-01-01

    Bridge programs, in which underprepared students gain the academic and technical skills necessary for college level courses and entry-level employment, are a promising initiative for expanding access to, and success in, community college education. For career pathways related to science, technology, engineering, or mathematics (STEM), bridge

  13. Teaching Elements and Principles of Bridge Design

    ERIC Educational Resources Information Center

    Beck, Charles

    2005-01-01

    Bridge construction is a popular classroom activity. However, the basic principles of tension, compression, and counterbalance are not always clearly represented and defined. The common materials used to construct model bridges, such as straws, toothpicks, Legos[TM], and building blocks, are often too flexible or stationary to demonstrate the…

  14. Statistical study on evaluating bridge health degree based on bridge inspection database

    NASA Astrophysics Data System (ADS)

    Otake, Yu; Sasuga, Takashi; Honjo, Yusuke; Murakami, Shigeyuki; Kobayashi, Koichi

    This paper presents results of an investigation of evaluating the bridges health degree of 54 bridges managed by Gifu Prefecture in Gifu City. Bridge health degree is statistically calculated with periodic inspection data conducted by Gifu Prefecture. This inspection results consist of many items and evaluate the state of bridge details, but a currently index is insufficient as one used to maintenance. Accordingly, the index is required that can evaluate overall of each bridge elements or entire bridge. So, this study aims to express health degree of bridge elements by one or two overall index with principal component analysis, and grasped relationship to calculated health index, age, specification, design standard and environmental condition by multiple regression analysis.

  15. Seismic response of steel suspension bridge

    SciTech Connect

    McCallen, D.B.; Astaneh-Asl, A.

    1996-11-01

    Performing accurate, realistic numerical simulations of the seismic response of long-span bridges presents a significant challenge to the fields of earthquake engineering and seismology. Suspension bridges in particular represent some of the largest and most important man-made structures and ensuring the seismic integrity of these mega-structures is contingent on accurate estimations of earthquake ground motions and accurate computational simulations of the structure/foundation system response. A cooperative, multi-year research project between the Univ. of California and LLNL was recently initiated to study engineering and seismological issues essential for simulating the response of major structures. Part of this research project is focused on the response of the long-span bridges with the San Francisco-Oakland Bay Bridge serving as a case study. This paper reports on the status of this multi-disciplinary research project with emphasis on the numerical simulation of the transient seismic response of the Bay Bridge.

  16. Level II scour analysis for Bridge 45 (CHELTH00440045) on Town Highway 44, crossing first Branch White River, Chelsea, Vermont

    USGS Publications Warehouse

    Ayotte, Joseph D.; Hammond, Robert E.

    1996-01-01

    bridge consisting of one 27-foot clear-span concrete-encased steel beam deck superstructure (Vermont Agency of Transportation, written commun., August 25, 1994). The bridge is supported by vertical, concrete abutments with wingwalls. The channel is skewed approximately 10 degrees to the opening while the opening-skew-to-roadway is 5 degrees. Both abutment footings were reported as exposed and the left abutment was reported to be undermined by 0.5 ft at the time of the Level I assessment. The only scour protection measure at the site was type-1 stone fill (less than 12 inches diameter) along the left abutment which was reported as failed. Additional details describing conditions at the site are included in the Level II Summary and Appendices D and E. Scour depths and rock rip-rap sizes were computed using the general guidelines described in Hydraulic Engineering Circular 18 (Richardson and others, 1993). Total scour at a highway crossing is comprised of three components: 1) long-term streambed degradation; 2) contraction scour (due to accelerated flow caused by a reduction in flow area at a bridge) and; 3) local scour (caused by accelerated flow around piers and abutments). Total scour is the sum of the three components. Equations are available to compute depths for contraction and local scour and a summary of the results of these computations follows. Contraction scour for all modelled flows ranged from 0.4 to 5.1 ft. with the worst-case occurring at the 500-year discharge. Abutment scour ranged from 9.9 to 20.3 ft. The worst-case abutment scour also occurred at the 500-year discharge. Additional information on scour depths and depths to armoring are included in the section titled “Scour Results”. Scoured-streambed elevations, based on the calculated scour depths, are presented in tables 1 and 2. A cross-section of the scour computed at the bridge is presented in figure 8. Scour depths were calculated assuming an infinite depth of erosive material and a homogeneous particle-size distribution. It is generally accepted that the Froehlich equation (abutment scour) gives “excessively conservative estimates of scour depths” (Richardson and others, 1993, p. 48). Many factors, including historical performance during flood events, the geomorphic assessment, scour protection measures, and the results of the hydraulic analyses, must be considered to properly ass

  17. Are arrhythmic hearts more complex ? Using skewness and the first-digit phenomenon to identify dynamical transitions in cardiac models

    E-print Network

    Seenivasan, Pavithraa; Sridhar, S; Sinha, Sitabhra

    2015-01-01

    Disruptions in the normal rhythmic functioning of the heart, termed as arrhythmia, often result from qualitative changes in the excitation dynamics of the organ. The transitions between different types of arrhythmia are accompanied by alterations in the spatiotemporal pattern of electrical activity that can be measured by observing the time-intervals between successive excitations of different regions of the cardiac tissue. In this paper we show that the distribution of these time-intervals exhibit a systematic change in their skewness during such dynamical transitions. Further, the leading digits of the normalized intervals appear to fit Benford's law better at these transition points. This raises the possibility of using these observations to design a clinical indicator for identifying changes in the nature of arrhythmia. More importantly, our results reveal an intriguing relation between the changing skewness of a distribution and its agreement with Benford's law, both of which have been independently prop...

  18. Development and Validation of a New Blade Element Momentum Skewed-Wake Model within AeroDyn: Preprint

    SciTech Connect

    Ning, S. A.; Hayman, G.; Damiani, R.; Jonkman, J.

    2014-12-01

    Blade element momentum methods, though conceptually simple, are highly useful for analyzing wind turbines aerodynamics and are widely used in many design and analysis applications. A new version of AeroDyn is being developed to take advantage of new robust solution methodologies, conform to a new modularization framework for National Renewable Energy Laboratory's FAST, utilize advanced skewed-wake analysis methods, fix limitations with previous implementations, and to enable modeling of highly flexible and nonstraight blades. This paper reviews blade element momentum theory and several of the options available for analyzing skewed inflow. AeroDyn implementation details are described for the benefit of users and developers. These new options are compared to solutions from the previous version of AeroDyn and to experimental data. Finally, recommendations are given on how one might select from the various available solution approaches.

  19. Non-skew-symmetric classical r-matrices, algebraic Bethe ansatz, and Bardeen-Cooper-Schrieffer-type integrable systems

    SciTech Connect

    Skrypnyk, T.

    2009-03-15

    We construct quantum integrable systems associated with non-skew-symmetric gl(2)-valued classical r-matrices. We find a new explicit multiparametric family of such the non-skew-symmetric classical r-matrices. We consider two classes of examples of the corresponding integrable systems, namely generalized Gaudin systems with and without an external magnetic field. In the case of arbitrary r-matrices diagonal in a standard gl(2)-basis, we calculate the spectrum of the corresponding quantum integrable systems using the algebraic Bethe ansatz. We apply these results to a construction of integrable fermionic models and obtain a wide class of integrable Bardeen-Cooper-Schrieffer (BCS)-type fermionic Hamiltonians containing the pairing and electrostatic interaction terms. We also consider special cases when the corresponding integrable Hamiltonians contain only pairing interaction term and are exact analogs of the 'reduced BCS Hamiltonian' of Richardson.

  20. Sign change of skew scattering induced anomalous Hall conductivity in epitaxial NiCo(002) films: band filling effect

    NASA Astrophysics Data System (ADS)

    Fan, W. J.; Ma, L.; Zhou, S. M.

    2015-03-01

    Tuning effects of the band filling and impurity distribution on the anomalous Hall effect are demonstrated in epitaxial face centered cubic NixCo1-x (002) films through the alloy composition. The anomalous Hall resistivity obeys the conventional scaling law, i.e. {?\\text{AH}}=a{?xx}+b? xx2 . It is interesting to find that in addition to the scattering independent parameter b, the skew parameter a also changes sign from negative to positive near the same Ni atomic concentration (x = 0.80) due to the band filling effects. The magnitude of the skew scattering parameter a shows a similar variation trend for the residual resistivity because of effects of the impurity distribution. This work might provide a clue to design and fabrication of high sensitivity Hall sensor.