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1

LOOKING WEST, BETWEEN READING DEPOT BRIDGE AND SKEW ARCH BRIDGE ...  

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

LOOKING WEST, BETWEEN READING DEPOT BRIDGE AND SKEW ARCH BRIDGE (HAER No. PA-116). - Philadelphia & Reading Railroad, Reading Depot Bridge, North Sixth Street at Woodward Street, Reading, Berks County, PA

2

http://rcc.its.psu.edu/hpc Guidelines for analyzing curved and skewed bridges and designing  

E-print Network

http://rcc.its.psu.edu/hpc Guidelines for analyzing curved and skewed bridges and designing them and skewed, I-girder/beam bridges continues to increase steadily throughout the country, certain aspects guidance for bridge engineers with respect to addressing construction issues during design. The effects

Bjørnstad, Ottar Nordal

3

Construction engineering of steel tub-girder bridge systems for skew effects  

NASA Astrophysics Data System (ADS)

Closed structural sections, such as those having circular, rectangular or trapezoidal shape, possess high rotational rigidity when compared to open sections such as I-girders. The high torsional rigidity of closed sections makes them ideal for use in highly curved bridges. In this case, the geometry of the bridge results in large torsional forces. Because of structural efficiency and economy reasons, most of these closed-section bridges consist of a trapezoidal cross-section, with a top concrete slab and bottom and side steel plates. The slab is cast after the steel is erected and thus a system of internal diaphragms and braces is necessary to stabilize the system during erection. During the steel erection and the early stages of the concrete deck placement, the section can be considered as quasi-closed as the top concrete flange has not been cast or is not yet effective. During steel erection, undetermined and/or large torsional forces and/or displacements may result in fit-up problems requiring large stresses to overcome. During concrete deck placement, the undetermined displacements can affect the control of the deck thickness and the final deck geometry, such as the alignment of deck joints and the matching of stages in phased constructions projects. Due to the interactions between their various components, the behavior of curved and skewed tub-girder bridges is significantly more complex than that of straight bridges. When skewed supports are used in tub-girders, the interaction of the girder bending rotations and the displacement constraints induced by the skewed support diaphragms causes twisting of the girders at the supports. These twist rotations introduce additional torques into the system. Both curvature and skew can cause design and construction difficulties, especially at the supports, where the corresponding steel dead load deflections and the large torsional stiffness of the girders may lead to large fit-up forces. Currently, the general understanding of the level of sophistication of analysis models required to properly predict forces and deformations of curved and/or skewed bridges during construction is limited. The development of guidelines regarding the sufficiency of simplified methods of structural analysis is the overall motivation and objective of this dissertation. This research addresses the construction load effects due to skew and due to combined skew and curvature and develops design recommendations and analytical tools for the construction engineering of tub-girder bridges. The effects of skew and curvature are studied by examining the results for different levels of analysis for 18 representative bridges. These bridges reflect the range of bridge curvature and skew used in current practice. By comparing the output from simplified analysis methods to validated refined 3D FEA solutions, general conclusions are developed as to when the simplified methods provide sufficient results. An important original contribution of this research is that the data generated constitutes the first systematic study on a large set of curved and skewed tub-girder bridges using consistent refined 3D FEA models to model construction forces and deformations. As such, the results of this research can serve as a benchmark for current and future improvements in methods of analysis and design for the construction engineering of curved and skewed tub-girder bridges. In the current research, this data has been used in both straight and curved tub-girder bridges to: • Develop a simplified 1D analysis method to account for the effect of skew on girder twist rotations and internal torques, • Evaluate the effect of skew on component forces, and propose improved simplified procedures to capture these effects, • Identify interactions between components and develop improved simplified analysis methods to account for these effects, • Establish limits for when the improved 1D and 2D simplified methods of analysis are sufficient for construction engineering analysis, and • Identify sources of steel erection fit-up proble

Jimenez Chong, Juan Manuel

4

Load distribution effects and repair procedures for existing skewed plate girder bridges  

E-print Network

single rolled section, such as a structural channel, or several rolled sections arranged to form a planar cross- frame, which is attached to vertical connection plates welded to the web plate of the girder. The function that diaphragms play...-to-flange fillet weld as well as at the toe of the connection plate weldment. It has been observed that, as the skew of the bridge increases, the degree of web gap cracking also increases (Fisher 1984). While the AASHTO specifications concerning the web gap...

Crozier, Allen R

2012-06-07

5

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

NASA Astrophysics Data System (ADS)

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.

Ghotbi, Abdoulreza

6

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

NASA Astrophysics Data System (ADS)

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.

Ghotbi, Abdoul R.

2014-09-01

7

Bridges  

NSDL National Science Digital Library

Bridges come in a wide variety of sizes, shapes, and lengths and are found all over the world. It is important that bridges are strong so they are safe to cross. Design and build a your own model bridge. Test your bridge for strength using a force sensor that measures how hard you pull on your bridge. By observing a graph of the force, determine the amount of force needed to make your bridge collapse.

Consortium, The C.

2012-05-21

8

Bridges  

NSDL National Science Digital Library

Through a five-lesson series that includes numerous hands-on activities, students are introduced to the importance and pervasiveness of bridges for connecting people to resources, places and other people, with references to many historical and current-day examples. In learning about bridge typesâarch, beam, truss and suspensionâstudents explore the effect of tensile and compressive forces. Students investigate the calculations that go into designing bridges; they learn about loads and cross-sectional areas by designing and testing the strength of model piers. Geology and soils are explored as they discover the importance of foundations, bearing pressure and settlement considerations in the creation of dependable bridges and structures. Students learn about brittle and ductile material properties. Students also learn about the many cost factors that comprise the economic considerations of bridge building. Bridges are unique challenges that take advantage of the creative nature of engineering.

Integrated Teaching And Learning Program

9

Bridges  

MedlinePLUS

... mouth where there is a lot of biting force. They also may not be the best choice if the wings will have to be small to avoid getting in the way of the bite or the gums. Getting a bridge requires at ...

10

2. Skewed view of E elevation of sugar mill looking ...  

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

2. Skewed view of E elevation of sugar mill looking NW. - Hacienda Azurarera Santa Elena, Sugar Mill Ruins, 1.44 miles North of PR Route 2 Bridge Over Rio De La Plata, Toa Baja, Toa Baja Municipio, PR

11

Skew critical problems  

E-print Network

Skew critical problems occur in continuous and discrete nonholonomic Lagrangian systems. They are analogues of constrained optimization problems, where the objective is differentiated in directions given by an apriori distribution, instead of tangent directions to the constraint. We show semiglobal existence and uniqueness for nondegenerate skew critical problems, and show that the solutions of two skew critical problems have the same contact as the problems themselves. Also, we develop some infrastructure that is necessary to compute with contact order geometrically, directly on manifolds.

C. Cuell; G. W. Patrick

2007-04-27

12

Skew-T Mastery  

NSDL National Science Digital Library

Meteorologists typically examine atmospheric soundings in the course of preparing a weather forecast. The skew-T / log-P diagram provides the preferred method for analyzing these soundings. This module comprehensively examines the use of the skew-T diagram. It explores thermodynamic properties, convective parameters, stability assessment, and several forecast applications. The module is designed for both instruction and reference. It also comes with an interactive Web-based skew-T diagram that calculates several common forecast parameters.

Comet

2006-10-04

13

Metric adjusted skew information  

E-print Network

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.

Frank Hansen

2006-07-23

14

Skew Killing spinors  

E-print Network

In this paper, we study the existence of a skew Killing spinor (see the definition below) on 2 and 3-dimensional Riemannian spin manifolds. We establish the integrability conditions and prove that these spinor fields correspond to twistor spinors in the two dimensional case while, up to a conformal change of the metric, they correspond to parallel spinors in the three dimensional case.

Habib, Georges

2011-01-01

15

Skew Killing spinors  

Microsoft Academic Search

In this paper, we study the existence of a skew Killing spinor (see the definition below) on 2 and 3-dimensional Riemannian spin manifolds. We establish the integrability conditions and prove that these spinor fields correspond to twistor spinors in the two dimensional case while, up to a conformal change of the metric, they correspond to parallel spinors in the three

Georges Habib; Julien Roth

2011-01-01

16

Skew Killing spinors Georges Habib  

E-print Network

Skew Killing spinors Georges Habib , Julien Roth Abstract In this paper, we study the existence of a skew Killing spinor (see the definition below) on 2 and 3-dimensional Riemannian spin manifolds. We constructions (see [4, 6] for results in this topic). A -Killing spinor is a smooth section of the spinor

Paris-Sud XI, Université de

17

Measuring Skewness: A Forgotten Statistic?  

ERIC Educational Resources Information Center

This paper discusses common approaches to presenting the topic of skewness in the classroom, and explains why students need to know how to measure it. Two skewness statistics are examined: the Fisher-Pearson standardized third moment coefficient, and the Pearson 2 coefficient that compares the mean and median. The former is reported in statistical…

Doane, David P.; Seward, Lori E.

2011-01-01

18

Skew resisting hydrodynamic seal  

DOEpatents

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.

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

2001-01-01

19

Flexible Class of Skew-Symmetric Distributions  

E-print Network

; Azzalini & Capitanio, 2003; Jones & Faddy, 2003; Sahu et al., 2003), skew-Cauchy (Arnold & Beaver, 2000) and other skew- elliptical ones (Azzalini & Capitanio, 1999; Branco & Dey, 2001; Sahu et al., 2003) can

Genton, Marc G.

20

Is a Brownian motion skew? Anotine Lejay  

E-print Network

Is a Brownian motion skew? Anotine Lejay Ernesto Mordecki Soledad Torres December 10, 2010 Abstract to the observation of a trajectory of a Skew Brownian motion, through a uniform time discretization. We charac in this case are non-classical, under the null hypothesis of the Skew Brownian motion being an usual Brownian

Paris-Sud XI, Université de

21

Is a Brownian motion skew? Antoine Lejay  

E-print Network

Is a Brownian motion skew? Antoine Lejay Ernesto Mordecki Soledad Torres February 26, 2013 Abstract to the observation of a trajectory of a Skew Brownian motion, through a uniform time discretization. We charac in this case are non-classical, under the null hypothesis of the Skew Brownian motion being an usual Brownian

22

Locally adaptive document skew detection  

NASA Astrophysics Data System (ADS)

This paper proposes a new approach to the detection of local orientation and skew in document images. It is based on the observation that there are many documents where a single global estimate of the page skew is not sufficient. These documents require local adaptation to deal robustly with todays complex configurations of components on the page. The approach attempts to identify regions in the image which exhibit locally consistent physical properties and consistent physical properties and consistent orientation. To do this, we rapidly compute a coarse segmentation and delineate regions which differ with respect to layout and/or physical content. Each region is classified as text, graphics, mixed text/graphics, image or background using local features and additional features are extracted to estimate orientation. The local orientation decisions are propagated where appropriate to resolve ambiguity and to produce a global estimate of the skew for the page. The implementation of our algorithms is demonstrated on a set of images which have multiple regions with different orientations.

Sauvola, Jaakko J.; Doermann, David S.; Pietikaeinen, Matti

1997-04-01

23

First Smart Bridge in Canada A. Guha-Thakurta  

E-print Network

smart prestressed concrete highway bridge built in Canada. A total of six pretensioned girdersSUMMARY First Smart Bridge in Canada A. Guha-Thakurta City of Calgary, Calgary, Alberta, Canada A of a continuous two span skew highway bridge were prestressed using carbon fibre composite cables (CrCC) developed

24

Categorical geometric skew Howe duality  

E-print Network

We categorify the R-matrix isomorphism between tensor products of minuscule representations of U_q(sl(n)) by constructing an equivalence between the derived categories of coherent sheaves on the corresponding convolution products in the affine Grassmannian. The main step in the construction is a categorification of representations of U_q(sl(2)) which are related to representations of U_q(sl(n)) by quantum skew Howe duality. The resulting equivalence is part of the program of algebro-geometric categorification of Reshitikhin-Turaev tangle invariants developed by the first two authors.

Cautis, Sabin; Licata, Anthony

2009-01-01

25

Kinematic correction for roller skewing  

NASA Technical Reports Server (NTRS)

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.

Savage, M.; Loewenthal, S. H.

1980-01-01

26

Standard Mastery Curves and Skew Curves.  

ERIC Educational Resources Information Center

The objective of the study is to convince educational researchers of the necessity for "standard mastery curves" for the graphical representation of scores on summative tests for a group of students. Attention is drawn to the study of theoretical and empirical skew curves in education and biology. Use of standard mastery curves and study of skew…

Warries, Egbert

27

Skewed Frequency Selective Surface Absorber  

NASA Astrophysics Data System (ADS)

In this paper, a skewed Frequency Selective Surface (FSS) absorber based on cross-dipole elements is presented. The proposed FSS design provides good frequency stability for oblique incidences. It provides better absorption rate for 5-GHz WLAN frequency band and allow other communication bands to pass through it. Also, the absorption in the stop-band reduces multipath fading of additional WLAN signals which occurred due to the placement of conducting/reflecting FSS. The FSS design consists of two layers; first layer consists of conducting cross-dipole and second layer consists of resistive cross-dipole placed in-front of the first layer. The periodicity of both elements is same. Asymmetric property is applied to FSS elements by taking a reference of central element. This technique leads to achieve a maximum stability in the stop-band. Simulated results demonstrated that the proposed FSS design has a stable frequency response for 5-GHz frequency band for both horizontal (TE) and vertical (TM) polarizations when the incident wave angle varied from 0 0 to 45 0.

Rafique, Umair; Khan, M. Arif; Afzal, M. Tausif; Malik, Fahad; Qasim, Shahzaib

2012-12-01

28

Why Is Platform Pricing Generally Highly Skewed?  

E-print Network

Bolt and Tieman (2008) suggested the prevalence of profit function non-concavity may account for the widespread use of skewed pricing by two-sided platform businesses. In both the Rochet-Tirole (2003) and Armstrong (2006) ...

Schmalensee, Richard

29

Nonwandering sets of interval skew products  

NASA Astrophysics Data System (ADS)

In this paper we consider a class of skew products over transitive subshifts of finite type with interval fibres. For a natural class of 1-parameter families we prove that for all but countably many parameter values the nonwandering set (in particular, the union of all attractors and repellers) has zero measure. As a consequence, the same holds for a residual subset of the space of skew products.

Kleptsyn, V.; Volk, D.

2014-07-01

30

Multivariate Skew-t Distributions in Econometrics and Environmetrics  

E-print Network

. . . . . . . . . . . . . . . . . . . . 84 2. Multivariate analysis . . . . . . . . . . . . . . . . . . . 92 E. Analysis of Automobile Prices . . . . . . . . . . . . . . . . 96 F. Log-Skew-Normal and Log-Skew-t Distributions . . . . . . 99 G. Conclusion.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 23 Summary statistics of automobile prices. . . . . . . . . . . . . . . . . 97 24 Skew-t model for automobile prices. . . . . . . . . . . . . . . . . . . . 98 25 Estimated moments of the skew-t fit to automobile prices. . . . . . . 98 26 Log...

Marchenko, Yulia V.

2012-02-14

31

Myocardial Bridge  

MedlinePLUS

... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart muscle that lies ... artery, instead of underneath it. With a myocardial bridge, part of a coronary artery dips into and ...

32

A skewed view of X chromosome inactivation  

PubMed Central

X chromosome inactivation involves a random choice to silence either X chromosome early in mammalian female development. Once silenced the inactive X is stably inherited through subsequent somatic cell divisions, and thus, females are generally mosaics, having a mixture of cells with one or the other parental X active. While in most females the number of cells with either X being active is roughly equal, skewing of X chromosome inactivation is observed in a percentage of women. In this issue of the JCI, Bolduc and colleagues address whether skewing of X chromosome inactivation in humans is influenced by an X-linked locus that can alter this initial random inactivation (see the related article beginning on page 333). Their data indicate that most of the skewing observed in humans results from secondary events rather than being due to an inherited tendency to inactivate a particular X chromosome. PMID:18097476

Minks, Jakub; Robinson, Wendy P.; Brown, Carolyn J.

2007-01-01

33

Skew chicane based betatron eigenmode exchange module  

DOEpatents

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.

Douglas, David (Yorktown, VA)

2010-12-28

34

Straw Bridges  

NSDL National Science Digital Library

Learners design, build and test a model bridge out of straws. The bridge must span 25 cm across a gap between two tables or two chairs. To measure the load, the bridge must securely hold a small cup. Learners test the load by placing as many pennies in the cup as possible and counting how many the bridge can hold.

Museum Of Science And Industry, Chicago

2012-01-01

35

On the time inhomogeneous skew Brownian motion  

E-print Network

This paper is devoted to the construction of a solution for the "Inhomogenous skew Brownian motion" equation, which first appeared in a seminal paper by Sophie Weinryb, and recently, studied by \\'{E}tor\\'e and Martinez. Our method is based on the use of the Balayage formula. At the end of this paper we study a limit theorem of solutions.

Bouhadou, S

2012-01-01

36

Associative skew clock routing for difficult instances  

E-print Network

including difficult instances based on an improved delay model. Experimental results show that our algorithm can reduce the total clock routing wirelength by 9%Â?15% compared to greedy-DME, which is one of the best zero skew routing algorithms....

Kim, Min-seok

2006-08-16

37

Multi-slice FE modeling of electrical machines with skewed slots-the skew discretization error  

Microsoft Academic Search

The simulation of rotating electrical machines with skewed slots by means of a multi-slice FE model is studied. Particular attention is devoted to the ensuing skew discretization error. As an alternative to the commonly adopted uniform distribution of the cross-sections along the shaft, a Gauss distribution is proposed. The application to a squirrel-cage induction motor under various working conditions shows

Johan J. C. Gyselinck; Lieven Vandevelde; Jan A. A. Melkebeek

2001-01-01

38

Reproductive skew in the Australian allodapine bee Exoneura robusta  

E-print Network

Reproductive skew in the Australian allodapine bee Exoneura robusta PHILIPP LANGER*, KATJA. number: 8170R) Uneven sharing of reproduction (reproductive skew) among members of a cooperative animal of reproduc- tion varies greatly among taxa, and reproductive skew models are evolutionary models that aim

Alvarez, Nadir

39

Fast Seamless Skew and Orientation Detection in Document Images  

Microsoft Academic Search

Reliable and generic methods for skew detection are a necessity for any large-scale digitization projects. As one of the first processing steps, skew detection and correction has a heavy influence on all further document analysis modules, such as geometric and logical layout analysis. This paper introduces a generic, scale-independent algorithm capable of accurately detecting the global skew angle of document

Iuliu Vasile Konya; Stefan Eickeler; Christoph Seibert

2010-01-01

40

Popsicle Bridge  

NSDL National Science Digital Library

In this activity, learners explore how engineering has impacted the development of bridges over time, including innovative designs and the challenge of creating bridges that become landmarks for a city. Learners work in teams of "engineers" to design and build their own bridge out of glue and popsicle sticks. Learners test their bridges using weights, evaluate their results, and present their findings to the group.

Ieee

2013-08-30

41

Spaghetti Bridge  

NSDL National Science Digital Library

Civil engineers design structures such as buildings, dams, highways and bridges. Student teams explore the field of engineering by making bridges using spaghetti as their primary building material. Then they test their bridges to see how much weight they can carry before breaking.

K-12 Outreach Office,

42

Clock tree synthesis for prescribed skew specifications  

E-print Network

. . . . . . . . . . . . . . . . . . . . . . . . . . 10 B. Delay Balancing . . . . . . . . . . . . . . . . . . . . . . . . 11 III ALGORITHM : : : : : : : : : : : : : : : : : : : : : : : : : : : : 14 A. Review of the Deferred-Merge Embedding (DME) Algorithm 14 1. Bottom-Up Phase: Construction of the Tree... that can achieve exact zero skew for any given abstract tree. In order to further reduce wirelength, 4 the DME (Deferred Merge Embedding) algorithm was developed in [11] according to the observation that there are multiple locations for a merging node...

Chaturvedi, Rishi

2005-08-29

43

Metric adjusted skew information: Convexity and restricted forms of superadditivity  

E-print Network

We give a truly elementary proof of the convexity of metric adjusted skew information following an idea of Effros. We extend earlier results of weak forms of superadditivity to general metric adjusted skew informations. Recently, Luo and Zhang introduced the notion of semi-quantum states on a bipartite system and proved superadditivity of the Wigner-Yanase-Dyson skew informations for such states. We extend this result to general metric adjusted skew informations. We finally show that a recently introduced extension to parameter values $ 1metric adjusted skew information.

Liang Cai; Frank Hansen

2009-07-30

44

Analysis of Parasite and Other Skewed Counts  

PubMed Central

Objective To review methods for the statistical analysis of parasite and other skewed count data. Methods Statistical methods for skewed count data are described and compared, with reference to those used over a ten year period of Tropical Medicine and International Health. Two parasitological datasets are used for illustration. Results Ninety papers were identified, 89 with descriptive and 60 with inferential analysis. A lack of clarity is noted in identifying measures of location, in particular the Williams and geometric mean. The different measures are compared, emphasizing the legitimacy of the arithmetic mean for skewed data. In the published papers, the t test and related methods were often used on untransformed data, which is likely to be invalid. Several approaches to inferential analysis are described, emphasizing 1) non-parametric methods, while noting that they are not simply comparisons of medians, and 2) generalized linear modelling, in particular with the negative binomial distribution. Additional methods, such as the bootstrap, with potential for greater use are described. Conclusions Clarity is recommended when describing transformations and measures of location. It is suggested that non-parametric methods and generalized linear models are likely to be sufficient for most analyses. PMID:22943299

Alexander, Neal

2012-01-01

45

Buckling analyses of composite laminate skew plates with material nonlinearity  

Microsoft Academic Search

A nonlinear material constitutive model, including a nonlinear in-plane shear formulation and the Tsai–Wu failure criterion, for fiber–composite laminate materials is employed to carry out finite element buckling analyses for composite laminate skew plates under uniaxial compressive loads. The influences of laminate layup, plate skew angle and plate aspect ratio on the buckling resistance of composite laminate skew plates are

Hsuan-Teh Hu; Chia-Hao Yang; Fu-Ming Lin

2006-01-01

46

EGARCH models with fat tails, skewness and leverage  

E-print Network

UNIVERSITY OF CAMBRIDGE Cambridge Working Papers in Economics EGARCH models with fat tails, skewness and leverage Andrew Harvey and Genaro Sucarrat CWPE 1236 EGARCH models with fat tails, skewness and leverage Andrew Harvey and Genaro... , recent examples being Zhu and Zinde-Walsh (2009), Zhu and Galbraith (2010), and Gomez et al (2007). In the context of changing variance, Giot and Laurent(2003, 2004) show that a skewed-t GARCH model (with leverage) does very well in predicting Value...

Harvey, Andrew; Sucarrat, Genaro

2012-08-17

47

Evolution and models for skewed parton distribution  

SciTech Connect

The authors discuss the structure of the ''forward visible'' (FW) parts of double and skewed distributions related to usual distributions through reduction relations. They use factorized models for double distributions (DDs) {tilde f}(x,{alpha}) in which one factor coincides with the usual (forward) parton distribution and another specifies the profile characterizing the spread of the longitudinal momentum transfer. The model DDs are used to construct skewed parton distributions (SPDs). For small skewedness, the FW parts of SPDs H ({tilde x},{xi}) can be obtained by averaging forward parton densities f({tilde x}-{xi}{alpha}) with the weight {rho}({alpha}) coinciding with the profile function of the double distribution {tilde f}(x, {alpha}) at small x. They show that if the x{sup n} moments {tilde f}{sub n}({alpha}) of DDs have the asymptotic (1-{alpha}{sup 2}){sup n+1} profile, then the {alpha}-profile of {tilde f}(x,{alpha}) for small x is completely determined by small-x behavior of the usual parton distribution. They demonstrate that, for small {xi}, the model with asymptotic profiles for {tilde f}{sub n}({alpha}) is equivalent to that proposed recently by Shuvaev et al., in which the Gegenbauer moments of SPDs do not depend on {xi}. They perform a numerical investigation of the evolution patterns of SPDs and give interpretation of the results of these studies within the formalism of double distributions.

Musatov, I.C.; Radyushkin, A.V.

1999-05-17

48

Konigsberg Bridge  

NSDL National Science Digital Library

The webpage provides an overview of how the Konigsberg Bridge problem led Euler to develop graph theory and establish the basis for topology. The page includes links to images of the bridge. It also includes an animated image which converts the map of Konigsberg into a graph.

2010-07-30

49

Straw Bridges  

NSDL National Science Digital Library

Working as engineering teams, students design and create model beam bridges using plastic drinking straws and tape as their construction materials. Their goal is to build the strongest bridge with a truss pattern of their own design, while meeting the design criteria and constraints. They experiment with different geometric shapes and determine how shapes affect the strength of materials. Let the competition begin!

Integrated Teaching And Learning Program

50

Active Bridging  

Microsoft Academic Search

Active networks accelerate network evolution by permitting the network infrastructure to be programmable, on a per-user, per-packet, or other basis. This programmability must be balanced against the safety and security needs inherent in shared resources.This paper describes the design, implementation, and performance of a new type of network element, an Active Bridge. The active bridge can be reprogrammed \\

D. Scott Alexander; Marianne Shaw; Scott M. Nettles; Jonathan M. Smith

1997-01-01

51

Cracked shells under skew-symmetric loading  

NASA Technical Reports Server (NTRS)

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.

Lelale, F.

1982-01-01

52

Learning a Novel Pattern through Balanced and Skewed Input  

ERIC Educational Resources Information Center

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…

McDonough, Kim; Trofimovich, Pavel

2013-01-01

53

FLECHT low flooding rate skewed test series data report. [PWR  

Microsoft Academic Search

The FLECHT Low Flooding Rate Tests were conducted in an improved original FLECHT Test Facility to provide heat transfer coefficient and entrainment data at forced flooding rates of 1 in.\\/sec. and with electrically heated rod bundles which had cosine and top skewed axial power profiles. The top-skewed axial power profile test series has now been successfully completed and is here

E. R. Rosal; C. E. Conway; M. C. Krepinevich

1977-01-01

54

Analysis of carbon dioxide concentration skewness at a rural site.  

PubMed

This paper provides evidence that symmetry of CO2 concentration distribution may indicate sources or dispersive processes. Skewness was calculated by different procedures with CO2 measured at a rural site using a Picarro G1301 analyser over a two-year period. The usual skewness coefficient was considered together with fourteen robust estimators. A noticeable contrast was obtained between day and night, and skewness decreased linearly with the logarithm of the height. One coefficient was selected from its satisfactory relationship with the median concentration in daily evolution. Three analyses based on the kernel smoothing method were conducted with this coefficient to investigate its response to yearly and daily evolutions, wind direction, and wind speed. Left-skewed distributions were linked to thermal turbulence during midday, especially in spring-summer, or with high wind speeds. Almost symmetric distributions were associated with sources, such as the Valladolid City plume reinforced with spring emissions and the lack of emissions in summer in the remaining directions. Finally, right-skewed distributions were related to low wind speeds and stable stratification at night, furthered by strong emissions in spring. Skewness intervals were proposed and their average median concentrations were calculated such that the relationship between skewness and concentration depends on the analysis performed. Since some skewness coefficients may also be negative, they provide better information about sources or dispersive processes than concentration. PMID:24463252

Pérez, Isidro A; Sánchez, M Luisa; García, M Ángeles; Ozores, Marta; Pardo, Nuria

2014-04-01

55

Colony nutrition skews reproduction in a social spider  

Microsoft Academic Search

Cooperative breeding societies are characterized by alloparental care and unequal distribution of reproduction (skewed reproduction). Competition for resources among group members may determine the reproductive outcome of each individual. In a spider colony, females feed together on prey and therefore may compete over the extraction of specific nutrients required for reproduction. Here we examined the occurrence of skewed reproduction in

Mor Salomon; David Mayntz; Yael Lubin

2008-01-01

56

Reproductive skew in female common marmosets: what can proximate mechanisms  

E-print Network

Review Reproductive skew in female common marmosets: what can proximate mechanisms tell us about of Obstetrics and Gynecology, and 5 Endocrinology-Reproductive Physiology Training Program, University 27708, USA Common marmosets are cooperatively breeding monkeys that exhibit high reproductive skew: most

Saltzman, Wendy

57

EXPLOSION POINTS IN SKEW MAPS Anne Stefanie Costolanski  

E-print Network

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

Sander, Evelyn

58

A Method for Controlling Skew on Linked Surfaces  

SciTech Connect

A new method for lessening skew in mapped meshes is presented. This new method involves progressive subdivision of a surface into loops consisting of four sides. Using these loops, constraints can then be set on the curves of the surface, which will propagate interval assignments across the surface, allowing a mesh with a better skew metric to be generated.

BENZLEY,STEVEN E.; KERR,ROBERT A.; MITCHELL,SCOTT A.; WHITE,DAVID R.

1999-09-27

59

Spaghetti Bridge  

NSDL National Science Digital Library

Play with your food while learning about engineering! Build a spaghetti bridge, then test its strength by piling on the marshmallows, raw spaghetti, raw linguine and coins. Investigate the difference between the strength of bridges made from flat and round building materials (spaghetti is round, while linguine is flat). Learn by doing that circles are among the strongest shapes in nature, and that external and internal stress distributes itself evenly throughout a round structure.

Sciencenter

1999-01-01

60

Skew Disperson and Continuity of Local Time  

NASA Astrophysics Data System (ADS)

Results are provided that highlight the effect of interfacial discontinuities in the diffusion coefficient on the behavior of certain basic functionals of the diffusion, such as local times and occupation times, extending previous results in (Appuhamillage et al., Ann Appl Probab 21:183-214, 2011; Water Resour Res 46:W07511, 2009) on the behavior of first passage times. The main goal is to obtain a characterization of large scale parameters and behavior by an analysis at the fine scale of stochastic particle motions. In particular, considering particle concentration modeled by a diffusion equation with piecewise constant diffusion coefficient, it is shown that the continuity of a natural modification of local time is the individual (stochastic) particle scale equivalent to continuity of flux at the scale of the (macroscopic) particle concentrations. Consequences of this involve the determination of a skewness transmission probability in the presence of an interface, as well as corollaries concerning interfacial effects on occupation time of the associated stochastic particles.

Appuhamillage, Thilanka A.; Bokil, Vrushali A.; Thomann, Enrique A.; Waymire, Edward C.; Wood, Brian D.

2014-07-01

61

Role of skew-symmetric differential forms in mathematics  

E-print Network

Skew-symmetric forms possess unique capabilities. The properties of closed exterior and dual forms, namely, invariance, covariance, conjugacy and duality, either explicitly or implicitly appear in all invariant mathematical formalisms. This enables one to see an internal connection between various branches of mathematics. However, the theory of closed exterior forms cannot be completed without an answer to a question of how the closed exterior forms emerge. In the present paper we discus essentially new skew-symmetric forms, which generate closed exterior forms. Such skew-symmetric forms, which are evolutionary ones, are derived from differential equations, and, in contrast to exterior forms, they are defined on nonintegrable manifolds.

L. I. Petrova

2010-04-05

62

Basswood Bridges  

NSDL National Science Digital Library

The Elementary Engineering Design course for freshmen students at Purdue University Calumet consists of two components: one ME and one EE. Due to the two part structure and in order to expose the students to the faculty, it is also team taught. The course counts as two credits, with the format one hour lecture and three hours lab. The basswood bridge is the major project of the ME half and counts for one quarter of the total course grade. The object, as is usual with bridge projects, is to design, build and test a truss bridge having a high strength to weight ratio. The design process includes statics analysis in combination with the tensile and compressive properties of the basswood. The details of the project from initial design to final testing are provided.

Abramowitz, Harvey

2009-09-16

63

Linking Bridges  

NSDL National Science Digital Library

This blog post presents three puzzles which provide an opportunity for learners to use the strategy of trial and error and logical reasoning. The challenge is to connect all of the islands with bridges so that the number on the island corresponds to the number of bridges going to it or from it. This activity also provides the opportunity for students to be puzzle designers by including a blank grid page on which students can design their own versions of the puzzle to share with classmates.

Young, David

2014-01-28

64

Skewed paternity and sex allocation in hermaphroditic plants and animals.  

PubMed Central

Models predict a reduced allocation to sperm when females preferentially use one of two males' sperm and the males do not know who is favoured. An analogous discounting occurs in plants when their paternity success is skewed by random, non-heritable factors such as location in the population and pollinator behaviour. We present a model that shows that skewed paternity can affect the sex allocation of hermaphrodites, that is it leads to a female-biased investment. The model highlights the close links between local mate competition and sperm competition. We use paternity data from Ficus in order to illustrate that skews in paternity success can lead to a high degree of sibling gamete competition in an apparently open breeding system. Since skews in paternity are ubiquitous in hermaphroditic plants and animals these findings should apply broadly. PMID:11600078

Greeff, J. M.; Nason, J. D.; Compton, S. G.

2001-01-01

65

Paper Bridge  

NSDL National Science Digital Library

In this engineering activity, challenge learners to construct a paper bridge that can support 100 pennies. Learners discover how they can make a weak material like paper strong enough to support a load pennies by changing the shape of the paper (by rolling, crumpling or folding it).

Boston, Wgbh

2002-01-01

66

Bridges, 2001.  

ERIC Educational Resources Information Center

This document is comprised of the one issue in volume 6 of "Bridges," a publication produced by the California Head Start-State Collaboration Office to detail the activities of the educational partnership and to provide relevant information to programs participating in the partnership. The Summer 2001 issue focuses on providing practitioners with…

Zito, Michael, Ed.

2001-01-01

67

Skewed exponential pairwise velocities from Gaussian initial conditions  

E-print Network

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.

Roman Juszkiewicz; Karl B. Fisher; Istvan Szapudi

1998-04-27

68

Bridged graphite oxide materials  

NASA Technical Reports Server (NTRS)

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.

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

2010-01-01

69

Reproductive skew and the threat of eviction: a new perspective  

PubMed Central

Most recent models of the partitioning of reproduction attempt to explain patterns of skew on the assumption that dominant individuals have complete control over breeding opportunities within the group, but may nevertheless concede a share of direct reproduction to subordinates as an incentive to remain peacefully in the association. Although these models may be applicable to some animal societies, we argue that they fail to provide a comprehensive theory of skew. Instead, we suggest that subordinates may often be able to claim unsanctioned reproduction for themselves, but will be forced to exercise a degree of reproductive restraint lest they incite ejection by the dominant. Reproductive skew, in other words, may reflect the threat of ejection (inducing subordinate restraint) rather than the threat of subordinate departure (inducing reproductive concessions by dominants). We present a simple ESS model of reproductive skew under these circumstances, which demonstrates that a shift in emphasis from reproductive concessions by dominants to reproductive restraint on the part of subordinates, radically alters the predictions of skew models. High group productivity, high relatedness and (when group members are related) strong ecological constraints are all expected to lead to reduced skew (the opposite conclusions to those of previous, concession-based analyses). The reason is that these factors reduce the benefits (or increase the costs) of ejection to the dominant, who therefore does best to tolerate more subordinate reproduction.

Johnstone, R. A.; Cant, M. A.

1999-01-01

70

Flow in Rotating Serpentine Coolant Passages With Skewed Trip Strips  

NASA Technical Reports Server (NTRS)

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.

Tse, David G.N.; Steuber, Gary

1996-01-01

71

Bridge Inspector's Training Manual.  

ERIC Educational Resources Information Center

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,…

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

72

Digital Bridges: Bridges of the Nineteenth Century  

NSDL National Science Digital Library

The collection consists of thirty representative 19th-century American bridge engineering monographs, manuals, and documents from the Lehigh University Libraries' Special Collections. The source documents have been scanned, converted to text, and partially corrected to make all significant terms and personal and proper names retrievable through the site's search engine. Topics include specific bridges (the Brooklyn Bridge, the East River Bridge), bridge types (suspension bridges, wrought iron bridges), bridge components (cabling, foundations), bridge design, bridge disasters, and others. The collection is browseable by title and searchable by keyword. Printable versions of the documents are also available. A glossary is also provided with definitions of terms, short biographies of authors, and descriptions of some of the bridges

2002-01-01

73

Building Bridges  

NSDL National Science Digital Library

In this lesson, students build bridges from arithmetical to algebraic thinking by exploring problems that are not limited to single-solution responses. Values organized into tables and graphs are used to move toward symbolic representations. Problem situations at the middle school level involve linear, quadratic, and exponential models. The site is valuable not only for its problems for students but also for the teaching strategy illustrated here.

Day, Roger; Illustrations, Nctm

2000-01-01

74

Bridge Building  

NSDL National Science Digital Library

This is a quick activity (on page 2 of the PDF) about how the arrangement of carbon atoms determines carbon's different properties. Learners will build bridges with Post-It notes that model two types of carbon molecules, graphite and carbon nanotubes, and test which structure of the same material can bear the weight of the most pennies. Also relates to linked video, DragonflyTV Nano: Hockey Sticks.

Twin Cities Public Television, Inc.

2008-01-01

75

Statistical analysis of highly skewed immune response data.  

PubMed

This paper considers methods of statistical analysis for highly skewed immune response data. Observations from population studies of immunological variables are rarely normally distributed between individuals; typically the distribution shows extreme levels of skewness. In some situations, skewness remains considerable even after transforming the data. Using resampling techniques, applied to several actual datasets of ELISA assay data, we consider the robustness of normal parametric methods, e.g. t tests and linear regression. Despite the skewness of the transformed data, we demonstrate that such methods are quite robust depending on the number of observations, type of analysis and severity of skewness. We also illustrate how bootstrap resampling can be used to provide a valid alternative method of analysis that can be used either for checking normal parametric analysis or as a direct method of analysis. We illustrate this combined approach by analysing real data to test for association between human serum antibodies to malaria merozoite surface proteins, MSP1 and MSP2, and resistance to clinical malaria, and confirm the protective effect of antibodies to MSP1 and demonstrated a similar protective effect for some antibodies to MSP2. PMID:9032413

McGuinness, D; Bennett, S; Riley, E

1997-02-14

76

Development of a baseline model for a steel girder bridge using remote sensing and load tests  

NASA Astrophysics Data System (ADS)

A new skewed two span continuous steel girder bridge was constructed and opened to traffic recently. This bridge uses high performance steel (HPS 100W) in the flanges of the negative moment region over the intermediate pier. For construction verification and long-term structural health monitoring purposes, a finite element (FE) model was developed for the bridge superstructure. Various field tests were performed to verify the model: 1) LiDAR scan, 2) static truck load tests, and 3) Laser doppler vibrometer testing. LiDAR scanner was introduced to gain geometrical information of the bridge in the real world. It was also used to measure girder deflections during load tests. The fundamental frequency of the bridge vibration was obtained by using a Laser doppler vibrometer. Both dynamic and static measurements are then used to update the FE model. This valid bridge superstructure FE model was provided to local DOT bridge engineers with the completion of this study.

Dai, Kaoshan; Chen, Shen-En; Scott, Jeremy; Schmieder, Marcus; Liu, Wanqiu; Hauser, Edd

2011-04-01

77

Bridge Builders  

NSDL National Science Digital Library

In this interactive game, students build bridges using fractional lengths in the form of fraction bars. Gap length may be known or unknown, entirely empty or partially filled. Fractions to fill the gap must be constructed in specific ways, using the four basic operations. After five tries at one level, the game resets. Note that the game sometimes expects particular answers: students may need to multiply 2/5 by 3 rather than multiplying 3/5 by 2, for example, even though both computations would produce the same result.

2010-01-01

78

Influence of surface roughness skewness on rolling contact fatigue life  

NASA Astrophysics Data System (ADS)

This paper evaluates the effects of randomly distributed small indentations, or pits, on the lubricating properties when operating under these mixed or boundary lubrication conditions. Rings and needle rollers were textured with randomly distributed small indentations, or pits, for evaluation. Skewness (Sk) was used as a measure of surface finish to characterize the degree to which the material of these modified parts was above the mean line, a positive value, or below the mean line, a negative value. Fatigue life tests were conducted on these rolling elements, whose skewness ranged from -1.2 to -2.0, under mixed or boundary lubrication conditions. Test results showed rolling bearing fatigue life to increase with a decrease in skewness as related to the depth, width, and distribution of the surface indentations, or pits, on the parts.

Akamatsu, Yoshinobu; Tsushima, Noriyuki; Goto, Toshihide; Hibi, Kenji

1992-10-01

79

Power and Skew Aware Point Diffusion Clock Network  

NASA Astrophysics Data System (ADS)

This letter presents point diffusion clock network (PDCN) with local clock tree synthesis (CTS) scheme. The clock network is implemented with ten times wider metal line space than typical mesh networks for low power and utilized to nine times smaller area CTS execution for minimized clock skew amount. The measurement results show that skew amount of PDCN with local CTS is reduced to 36% and latency is shrunk to 45% of the amount in a 4.81mm2 CortexA-8 core with 65nm Samsung process.

Jung, Gunok; Kim, Chunghee; Chae, Kyoungkuk; Park, Giho; Park, Sung Bae

80

Building Big: Bridges  

NSDL National Science Digital Library

This web page describes different aspects of designing bridges. It relates the concept of bridge designing with the real life scenarios. It also includes some bridges around the world and gives some specifications of them.

Foundation, Wgbh E.

2006-07-11

81

Building Big--Bridges  

NSDL National Science Digital Library

This web page describes different aspects of designing bridges. It relates the concept of bridge designing with the real life scenarios. It also includes some bridges around the world and gives some specifications of them.

2008-05-22

82

Skewed contraceptive method mix: why it happens, why it matters.  

PubMed

Contraceptive prevalence has been central to family planning research over the past few decades, but researchers have given surprisingly little consideration to method mix, a proxy for method availability or choice. There is no 'ideal' method mix recognized by the international community; however, there may be reason for concern when one or two methods predominate in a given country. In this article method skew is operationally defined as a single method constituting 50% or more of contraceptive use in a given country. Of 96 countries examined in this analysis, 34 have this type of skewed method mix. These 34 countries cluster in three groups: (1) sixteen countries in which traditional methods dominate, most of which are in sub-Saharan Africa; (2) four countries in which female sterilization predominates (India, Brazil, Dominican Republic and Panama); and (3) fourteen countries that rely on a single reversible method (the pill in Algeria, Kuwait, Liberia, Morocco, Sudan and Zimbabwe; the IUD in Cuba, Egypt, Kazakhstan, Kyrgyz Republic, Moldova, Turkmenistan and Uzbekistan; and the injectable in Malawi). A review of available literature on method choice in these countries provides substantial insight into the different patterns of method skew. Method skew in some countries reflects cultural preferences or social norms. Yet it becomes problematic if it stems from restrictive population policies, lack of access to a broad range of methods, or provider bias. PMID:16762087

Sullivan, Tara M; Bertrand, Jane T; Rice, Janet; Shelton, James D

2006-07-01

83

Distributed, Secure Load Balancing with Skew, Heterogeneity, and Churn  

E-print Network

Distributed, Secure Load Balancing with Skew, Heterogeneity, and Churn Jonathan Ledlie and Margo (heterogeneity). Other approaches tackle these less-than- ideal conditions, but give up on important security throughput by 20% in a widely heterogeneous system in our experiments. I. INTRODUCTION Decentralized

84

SKEW PRODUCTS, QUANTITATIVE RECURRENCE, SHRINKING TARGETS AND DECAY OF CORRELATIONS  

E-print Network

.g. [35, 25, 17, 28]) . nonlinear analysis in recurrence plots (see e.g. [27]). Quite recent resultsSKEW PRODUCTS, QUANTITATIVE RECURRENCE, SHRINKING TARGETS AND DECAY OF CORRELATIONS STEFANO dynamical systems. We prove that its quantitative recurrence (also with respect to given observables

Saussol, Benoît

85

SKEW PRODUCTS, QUANTITATIVE RECURRENCE, SHRINKING TARGETS AND DECAY OF CORRELATIONS  

E-print Network

, 25, 17, 28]) · nonlinear analysis in recurrence plots (see e.g. [27]). Quite recent results showedSKEW PRODUCTS, QUANTITATIVE RECURRENCE, SHRINKING TARGETS AND DECAY OF CORRELATIONS STEFANO systems. We prove that its quantitative recurrence (also with respect to given observables) and hitting

Saussol, Benoît

86

SKEW PRODUCTS, QUANTITATIVE RECURRENCE, SHRINKING TARGETS AND DECAY OF CORRELATIONS  

E-print Network

for the geodesic flow and similar(see e.g. [35, 25, 17, 28]) · nonlinear analysis in recurrence plots (see e.g. [27SKEW PRODUCTS, QUANTITATIVE RECURRENCE, SHRINKING TARGETS AND DECAY OF CORRELATIONS STEFANO systems. We prove that its quantitative recurrence (also with respect to given observables) and hitting

Boyer, Edmond

87

Summarizing and Mining Skewed Data Streams Graham Cormode  

E-print Network

Summarizing and Mining Skewed Data Streams Graham Cormode S. Muthukrishnan Abstract Many applications generate massive data streams. Sum- marizing such massive data requires fast, small space algo- rithms to support post-hoc queries and mining. An important observation is that such streams are rarely

88

Casting with Skewed Ejection Direction Hee-Kap Ahn1  

E-print Network

Casting with Skewed Ejection Direction Hee-Kap Ahn1 Siu-Wing Cheng2 Otfried Cheong3 Abstract Casting is a manufacturing process in which liquid is poured into a cast (mould) that has a cavity with the shape of the object to be manufactured. The liquid then hardens, after which the cast is removed. We

Cheng, Siu-Wing

89

Build A Bridge  

NSDL National Science Digital Library

This wonderful site, provided by NOVA Online, brings to life the engineering challenges inherent to bridge-building. Designed for those who want the challenge, the site offers four bridging scenarios (with photos): "a 5,000-foot span across an ocean bay where huge ships come and go, ... a 700-foot span across a deep canyon gorge," and two others. A step-by-step tutorial teaches about four different bridge types (arch, beam, suspension, and cable-stayed), after which the user may select a bridge type for each scenario. The site is enhanced by links to other bridge resources, such as the famous bridge-building disaster of the century (Tacoma Narrows Bridge) and the Golden Gate Bridge site, which in turn, links users to other famous bridges including Japan's brand new Akashi Kaikyo Bridge, the longest bridge in the world.

1997-01-01

90

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

DOEpatents

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.

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

1998-01-01

91

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

DOEpatents

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.

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

1998-01-13

92

ORIGINAL ARTICLE A test of reproductive skew models in a field population  

E-print Network

ORIGINAL ARTICLE A test of reproductive skew models in a field population of a multiple-queen ant R the evolutionary basis of variation in reproductive skew (degree of sharing of reproduction among coexisting individuals) is an important task both because skew varies widely across social taxa and because testing

Alvarez, Nadir

93

Numerical and experimental analyses of an integral bridge  

NASA Astrophysics Data System (ADS)

In this paper, we present the analysis of a numerical and an experimental study of the Scotch Road integral abutment bridge located in Trenton, NJ, USA. Three-dimensional, nonlinear finite element (FE) model of the full bridge has been developed to study the effect of thermal loading on the bridge substructure. The bridge substructure was fully instrumented. Data analysis was performed to study the effect of several design parameters on axial stress in piles. An analysis of the pile-soil system was performed using the finite difference software LPILE. The maximum displacement of the bridge superstructure obtained from the FE model due to a maximum expected temperature change of ±42°C during the lifetime of the bridge was applied to the substructure model. The effect of bridge skew on the build-up of soil pressure behind the abutment was studied. A significant increase in the soil pressures and axial stresses behind the abutment at the obtuse side versus the acute was observed. The effect of the size of the galvanized steel sleeve on the induced axial stresses in piles was studied. We found that increasing the size of the steel sleeve increases their capacity to resist bending.

Khodair, Yasser; Hassiotis, Sophia

2013-12-01

94

Universal relation between skewness and kurtosis in complex dynamics  

NASA Astrophysics Data System (ADS)

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.

Cristelli, Matthieu; Zaccaria, Andrea; Pietronero, Luciano

2012-06-01

95

Skewed Brownian Fluctuations in Single-Molecule Magnetic Tweezers  

PubMed Central

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

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

2014-01-01

96

Newspaper Coverage of Intimate Partner Violence: Skewing Representations of Risk  

PubMed Central

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

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

2011-01-01

97

Skew Divergence-Based Fuzzy Segmentation of Rock Samples  

NASA Astrophysics Data System (ADS)

Digital image segmentation is a process in which one assigns distinct labels to different objects in a digital image. The MOFS (Multi Object Fuzzy Segmentation) algorithm has been successfully applied to the segmentation of images from several modalities. However, the traditional MOFS algorithm fails when applied to images whose composing objects are characterized by textures whose patterns cannot be successfully described by simple statistics computed over a very restricted area. Here, we present an extension of the MOFS algorithm that achieves the segmentation of textures by employing adaptive affinity functions that use the Skew Divergence as a measure of distance between two distributions. These affinity functions are called adaptive because their associated area (neighborhood) changes according to the characteristics of the texture being processed. We performed experiments on mosaic images composed by combining rock sample images which show the effectiveness of the adaptive skew divergence based fuzzy affinity functions.

Carvalho, Bruno M.; Garduño, Edgar; Santos, Iraçú O.

2014-03-01

98

Minority report in fraud detection: classification of skewed data  

Microsoft Academic Search

This paper proposes an innovative fraud detection method, built upon existing fraud detection research and Minority Report, to deal with the data mining problem of skewed data distributions. This method uses backpropagation (BP), together with naive Bayesian (NB) and C4.5 algorithms, on data partitions derived from minority oversampling with replacement. Its originality lies in the use of a single meta-classifier

Clifton Phua; Damminda Alahakoon; Vincent Lee

2004-01-01

99

Double diffraction at a pair of coplanar skew edges  

Microsoft Academic Search

A high-frequency solution is presented for the scattering in the near zone by a pair of coplanar skew edges when they are illuminated by a source at a finite distance. The solution is obtained by using a spherical-wave spectral representation of the first-order diffracted field from each edge. The final closed-form asymptotic solution includes terms up to the second order.

Filippo Capolino; I. M. Albani; Stefano Maci; Roberto Tiberio

1997-01-01

100

On the bounded-skew clock and Steiner routing problems  

Microsoft Academic Search

We study the minimum-cost bounded-skewrouting tree (BST) problemunder the linear delay model. This problem captures severalengineering tradeoffs in the design of routing topologies with controlledskew. We propose three tradeoff heuristics. (1) For a fixedtopology Extended-DME (Ex-DME) extends the DME algorithmfor exact zero-skew trees via the concept of a merging region. (2)For arbitrary topology and arbitrary embedding, Extended GreedyDME (ExG-DME) very

Dennis J.-H. Huang; Andrew B. Kahng; Chung-Wen Albert Tsao

1995-01-01

101

Left-App rings of skew generalized power series  

Microsoft Academic Search

A ring $R$ is called a left APP-ring if the left annihilator $l_{R}(Ra)$ is right $s$-unital as an ideal of $R$ for any $a\\\\in R$. Let $R$ be a ring, $(S,\\\\leq)$ a strictly ordered monoid and $\\\\omega:S\\\\longrightarrow {\\\\rm End}(R)$ a monoid homomorphism. The skew generalized power series ring $[[R^{S,\\\\leq},\\\\omega

Renyu Zhao

2010-01-01

102

Incorporating Skew into RMS Surface Roughness Probability Distribution  

NASA Technical Reports Server (NTRS)

The standard treatment of RMS surface roughness data is the application of a Gaussian probability distribution. This handling of surface roughness ignores the skew present in the surface and overestimates the most probable RMS of the surface, the mode. Using experimental data we confirm the Gaussian distribution overestimates the mode and application of an asymmetric distribution provides a better fit. Implementing the proposed asymmetric distribution into the optical manufacturing process would reduce the polishing time required to meet surface roughness specifications.

Stahl, Mark T.; Stahl, H. Philip.

2013-01-01

103

Kurtosis, skewness, and non-Gaussian cosmological density perturbations  

NASA Technical Reports Server (NTRS)

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.

Luo, Xiaochun; Schramm, David N.

1993-01-01

104

Skew-symmetric differential forms. Invariants. Realization of invariant structures  

E-print Network

Skew-symmetric differential forms play an unique role in mathematics and mathematical physics. This relates to the fact that closed exterior skew-symmetric differential forms are invariants. The concept of "Exterior differential forms" was introduced by E.Cartan for a notation of integrand expressions, which can create the integral invariants.(The existence of integral invariants was recognized by A.Poincare while studying the general equations of dynamics.) All invariant mathematical formalisms are based on invariant properties of closed exterior forms. The invariant properties of closed exterior forms explicitly or implicitly manifest themselves essentially in all formalisms of field theory, such as the Hamilton formalism, tensor approaches, group methods, quantum mechanics equations, the Yang-Mills theory and others. They lie at the basis of field theory. However, in this case the question of how the closed exterior forms are obtained arises. In present work it is shown that closed exterior forms, which possess the invariant properties, are obtained from skew-symmetric differential forms, which, as contrasted to exterior forms, are defined on nonintegrable manifolds. The process of generating closed exterior forms describes the mechanism of realization of invariants and invariant structures.

L. I. Petrova

2009-01-13

105

Science Shorts: Building Bridges  

NSDL National Science Digital Library

London Bridge is falling down, falling down...Can you finish the song? Although there are various stories that suggest the meaning of this famous nursery rhyme, the London Bridge, which spans the River Thames, did indeed "fall down" several times throughout history. This month's Science Shorts explores what makes bridges stay up. A corresponding activity is included.

Adams, Barbara

2006-07-01

106

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 ...

107

Effect of Resonator Axis Skew on Normal Incidence Impedance  

NASA Technical Reports Server (NTRS)

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.

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

2003-01-01

108

Techniques to estimate generalized skew coefficients of annual peak streamflow for natural basins in Texas  

USGS Publications Warehouse

This report presents two techniques to estimate generalized skew coefficients used for log-Pearson Type III peak-streamflow frequency analysis of natural basins in Texas. A natural basin has less than 10 percent impervious cover, and less than 10 percent of its drainage area is controlled by reservoirs. The estimation of generalized skew coefficients is based on annual peak and historical peak streamflow for all U.S. Geological Survey streamflow-gaging stations having at least 20 years of annual peak-streamflow record from natural basins in Texas. Station skew coefficients calculated for each of 255 Texas stations were used to estimate generalized skew coefficients for Texas. One technique to estimate generalized skew coefficients involved the use of regression equations developed for each of eight regions in Texas, and the other involved development of a statewide map of generalized skew coefficients. The weighted mean of the weighted mean standard errors of the regression equations for the eight regions is 0.36 log10 skew units, and the weighted mean standard error of the map is 0.35 log10 skew units. The technique based on the map is preferred for estimating generalized skew coefficients because of its smooth transition from one region of the State to another.

Judd, Linda J.; Asquith, William H.; Slade, Raymond M., Jr.

1996-01-01

109

Skewness and shock formation in laboratory-scale supersonic jet data.  

PubMed

Spatial properties of noise statistics near unheated, laboratory-scale supersonic jets yield insights into source characteristics and near-field shock formation. Primary findings are (1) waveforms with positive pressure skewness radiate from the source with a directivity upstream of maximum overall level and (2) skewness of the time derivative of the pressure waveforms increases significantly with range, indicating formation of shocks during propagation. These results corroborate findings of a previous study involving full-scale engine data. Further, a comparison of ideally and over-expanded laboratory data show that while derivative skewness maps are similar, waveform skewness maps are substantially different for the two cases. PMID:23742445

Gee, Kent L; Neilsen, Tracianne B; Atchley, Anthony A

2013-06-01

110

COMPENSATION OF FAST KICKER ROLLS WITH SKEW QUADRUPOLES  

SciTech Connect

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.

Pinayev, I.

2011-03-28

111

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

112

BridgeSPA: Improving Tor Bridges with Single Packet Authorization  

E-print Network

BridgeSPA: Improving Tor Bridges with Single Packet Authorization Rob Smits rdfsmits of the publicly listed relays. To deal with such an adversary, Tor uses bridges, which are unlisted relays's bridge implementation make it easy to dis- cover large numbers of bridges. An adversary that hoards

Hengartner, Urs

113

Soft bounds on diffusion produce skewed distributions and Gompertz growth  

NASA Astrophysics Data System (ADS)

Constraints can affect dramatically the behavior of diffusion processes. Recently, we analyzed a natural and a technological system and reported that they perform diffusion-like discrete steps displaying a peculiar constraint, whereby the increments of the diffusing variable are subject to configuration-dependent bounds. This work explores theoretically some of the revealing landmarks of such phenomenology, termed "soft bound." At long times, the system reaches a steady state irreversibly (i.e., violating detailed balance), characterized by a skewed "shoulder" in the density distribution, and by a net local probability flux, which has entropic origin. The largest point in the support of the distribution follows a saturating dynamics, expressed by the Gompertz law, in line with empirical observations. Finally, we propose a generic allometric scaling for the origin of soft bounds. These findings shed light on the impact on a system of such "scaling" constraint and on its possible generating mechanisms.

Mandrà, Salvatore; Lagomarsino, Marco Cosentino; Gherardi, Marco

2014-09-01

114

Soft bounds on diffusion produce skewed distributions and Gompertz growth  

E-print Network

Constraints can affect dramatically the behavior of diffusion processes. Recently, we analyzed a natural and a technological system and reported that they perform diffusion-like discrete steps displaying a peculiar constraint, whereby the increments of the diffusing variable are subject to configuration-dependent bounds. This work explores theoretically some of the revealing landmarks of such phenomenology, termed "soft bound". At long times, the system reaches a steady state irreversibly (i.e., violating detailed balance), characterized by a skewed "shoulder" in the density distribution, and by a net local probability flux, which has entropic origin. The largest point in the support of the distribution follows a saturating dynamics, expressed by the Gompertz law, in line with empirical observations. Finally, we propose a generic allometric scaling for the origin of soft bounds. These findings shed light on the impact on a system of such "scaling" constraint and on its possible generating mechanisms.

Mandrà, Salvatore; Gherardi, Marco

2014-01-01

115

Abundant rich phase transitions in step-skew products  

NASA Astrophysics Data System (ADS)

We study phase transitions for the topological pressure of geometric potentials of transitive sets. The sets considered are partially hyperbolic having a step-skew product dynamics over a horseshoe with one-dimensional fibres corresponding to the central direction. The sets are genuinely non-hyperbolic, containing intermingled horseshoes of different hyperbolic, behaviour (contracting and expanding centre). We construct for every k ? 1 a diffeomorphism F with a transitive set ? as above such that the pressure map P(t) = P(t ?) of the potential \\varphi= -log \\,\\Vert \\rmd F|_{E^c}\\Vert (Ec the central direction) defined on ? has k rich phase transitions. This means that there are parameters t?, ? = 0, …, k - 1, where P(t) is not differentiable and this lack of differentiability is due to the coexistence of two equilibrium states of t? ? with positive entropy and different Birkhoff averages. Each phase transition is associated with a gap in the central Lyapunov spectrum of F on ?.

Díaz, L. J.; Gelfert, K.; Rams, M.

2014-09-01

116

Guaranteeing Convergence of Iterative Skewed Voting Algorithms for Image Segmentation  

PubMed Central

In this paper we provide rigorous proof for the convergence of an iterative voting-based image segmentation algorithm called Active Masks. Active Masks (AM) was proposed to solve the challenging task of delineating punctate patterns of cells from fluorescence microscope images. Each iteration of AM consists of a linear convolution composed with a nonlinear thresholding; what makes this process special in our case is the presence of additive terms whose role is to “skew” the voting when prior information is available. In real-world implementation, the AM algorithm always converges to a fixed point. We study the behavior of AM rigorously and present a proof of this convergence. The key idea is to formulate AM as a generalized (parallel) majority cellular automaton, adapting proof techniques from discrete dynamical systems. PMID:22984338

Balcan, Doru C.; Srinivasa, Gowri; Fickus, Matthew; Kovacevic, Jelena

2012-01-01

117

Semiconductor bridge (SCB) detonator  

DOEpatents

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.

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

1999-01-19

118

On the Boundedness and Skew-Symmetric Properties of the Inertia and Coriolis  

E-print Network

On the Boundedness and Skew-Symmetric Properties of the Inertia and Coriolis Matrices for Vehicle, Norway Abstract: This paper addresses the boundedness property of the inertia matrix and the skew for the boundedness property of the inertia matrix which for a bad choice of state variables will not necessarily hold

Gravdahl, Jan Tommy

119

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

Microsoft Academic Search

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

Pamela L. Reynolds; John F. Bruno

2012-01-01

120

Interval estimators for the population mean for skewed distributions with a small sample size  

E-print Network

Interval estimators for the population mean for skewed distributions with a small sample size Glen for skewed distributions with a small sample size SUMMARY In finite population sampling it has long been developed which is based on the `Polya posterior'. For large sample sizes these methods often closely mimic

Meeden, Glen

121

POPULATION GENETICS MODELS WITH SKEWED FERTILITIES: A FORWARD AND BACKWARD ANALYSIS  

E-print Network

POPULATION GENETICS MODELS WITH SKEWED FERTILITIES: A FORWARD AND BACKWARD ANALYSIS THIERRY HUILLET, MARTIN M¨OHLE Abstract. Discrete population genetics models with unequal (skewed) fertil- ities. For each class the asymptotic behavior as the total population size N tends to infinity is investigated

Paris-Sud XI, Université de

122

An elementary approach to dynamics and bifurcations of skew tent maps  

E-print Network

An elementary approach to dynamics and bifurcations of skew tent maps Torsten Lindstr¨om School In this paper the dynamics of skew tent maps are classified in terms of two bifurcation parameters. In time; difference equation; chaos; bifurcation diagram; uni- modal map. AMS2000 Subject classification codes 37E05

Thunberg, Hans

123

Whisenhunt, Todd Walter. Measurement and Finite Element Modeling of the Non-Composite Deflections of Steel Plate Girder Bridges. (Under the direction of Emmett  

E-print Network

Bolentown, South Carolina. After the completion of his first Bachelor of Science degree in Agricultural of skewed and stage-constructed bridges is a problem that has resulted in many costly construction delays analysis method over predicts the non-composite deflections by an average of 38 percent for the interior

124

SULPHITE BRIDGE FROM DOWNSTREAM, BEARING NORTHEAST 25 DEGREES. THE BRIDGE ...  

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

SULPHITE BRIDGE FROM DOWNSTREAM, BEARING NORTHEAST 25 DEGREES. THE BRIDGE ONCE HAD VERTICAL BOARD SIDING BUT VANDALS BURNED IT OFF IN 1981 - Sulphite Railroad Bridge, Former Boston & Maine Railroad (originally Tilton & Franklin Railroad) spanning Winnipesautee River, Franklin, Merrimack County, NH

125

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

126

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

127

Modelling a Suspension Bridge.  

ERIC Educational Resources Information Center

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)

Rawlins, Phil

1991-01-01

128

Bridge Program Planning Guide  

NSDL National Science Digital Library

This report discusses bridge training programs which are designed to "prepare individuals without the requisite basic skills for postsecondary training leading to career-path employment and further learning in a specific industry or occupational sector." This guide is intended to help those representing community colleges, community organizations, and others plan the development of bridge training programs.

Jenkins, Davis

2012-01-26

129

The effect of forward skewed rotor blades on aerodynamic and aeroacoustic performance of axial-flow fan  

Microsoft Academic Search

Based on comparative experiment, this paper deals with using tangentially skewed rotor blades in axial-flow fan. It is seen from the comparison of the overall performance of the fan with skewed bladed rotor and radial bladed rotor that the skewed blades operate more efficiently than the radial blades, especially at low volume flows. Meanwhile, decrease in pressure rise and flow

Jun Wei; Fangyuan Zhong

1988-01-01

130

Sociality, mating system and reproductive skew in marmots: evidence and hypotheses.  

PubMed

Marmot species exhibit a great diversity of social structure, mating systems and reproductive skew. In particular, among the social species (i.e. all except Marmota monax), the yellow-bellied marmot appears quite different from the others. The yellow-bellied marmot is primarily polygynous with an intermediate level of sociality and low reproductive skew among females. In contrast, all other social marmot species are mainly monogamous, highly social and with marked reproductive skew among females. To understand the evolution of this difference in reproductive skew, I examined four possible explanations identified from reproductive skew theory. From the literature, I then reviewed evidence to investigate if marmot species differ in: (1) the ability of dominants to control the reproduction of subordinates; (2) the degree of relatedness between group members; (3) the benefit for subordinates of remaining in the social group; and (4) the benefit for dominants of retaining subordinates. I found that the optimal skew hypothesis may apply for both sets of species. I suggest that yellow-bellied marmot females may benefit from retaining subordinate females and in return have to concede them reproduction. On the contrary, monogamous marmot species may gain by suppressing the reproduction of subordinate females to maximise the efficiency of social thermoregulation, even at the risk of departure of subordinate females from the family group. Finally, I discuss scenarios for the simultaneous evolution of sociality, monogamy and reproductive skew in marmots. PMID:11074309

Allainé

2000-10-01

131

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

USGS Publications Warehouse

[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.

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

2004-01-01

132

Bay Bridge 360  

NSDL National Science Digital Library

This website was created by the various California transportation agencies that are involved in the enormous job of retrofitting the San Francisco-Oakland Bay Bridge to protect it from being damaged by seismic activity. It is an extremely well thought out website, with an interactive aerial graphic of the Bridge on its homepage that introduces visitors to their work. If you click on the colored circles on the bridge, you can see a slideshow of the construction on that section of the Bridge, and some of the Bridge sections include a time-lapse video of the construction. Additionally, there is a short film visitors can watch to get an overview of the project, by clicking on the blue circle above "Bay Bridge Overview" in the right-hand corner of the homepage. Clicking on the arrow in the left-hand corner of the homepage takes you inside the website where you can find links to "Closures and Detours", "Environmental Issues", for the Final Environmental Impact Statement, detailed explanations of the construction methods under the "Information Center" link, and even "Construction Cams". If you just can't get enough of traffic where you live, just click on "Construction Cams" and see Bay Bridge traffic.

2009-06-08

133

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

134

M.E. Bridges 1 MELISSA E. BRIDGES  

E-print Network

M.E. Bridges 1 MELISSA E. BRIDGES melbrid@gmail.com Education: Ph.D. Ecology Presentations and Publications): Bridges, M., B.D. Maxwell, and L.J. Rew. 2010. The role of current and historic. 7-11. Denver, CO. [Oral presentation]. Bridges, M., D.L. Shaner, and P. Westra. 2009. The effects

Maxwell, Bruce D.

135

Bridge : an unraveled architecture  

E-print Network

The bridge is an inhabitable structure housing live/work artists studios, galleries and workshops. It is an urban/architectural/personal intervention that strives to explore issues of Iatent/potential narratives within a ...

ElHusseiny, Ahmed

2006-01-01

136

Semiconductor bridge (SCB) igniter  

SciTech Connect

An explosive device is described comprising: a non electrically conducting substrate; an electrical material mounted on the substrate and having a negative temperature coefficient of electrical resistivity at an elevated temperature. The material covers an area of the substrate and defines a pair of spaced pads connected by a bridge; a metallized layer covering each of the spaced pads; an electrical conductor connected to each of the metallized layers, whereby the electrical resistance between the electrical conductors is substantially determined by the electrical resistance of the bridge; and an explosive material covering the device, the area of the bridge in contact with the explosive material being sufficient to ignite the explosive material when the bridge forms a plasma due to electrical current passing therethrough.

Bickes, R.W. Jr.; Schwartz, A.C.

1987-11-24

137

Bridge Rectifier Animation  

NSDL National Science Digital Library

This is an animation of a bridge rectifier circuit or diode bridge. Voltages and parts of the circuit of this 3-D animated gif are highlighted with different colors. Current is displayed by green arrows indicating directional flow. The animation requires a Web browser or other video player software capable of displaying gif animations. A link provides an optional Quicktime version of this same animation.Other 3-D Circuit Animations can be seen here.

2009-11-26

138

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

NASA Technical Reports Server (NTRS)

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.

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

1994-01-01

139

Qualitative investigation of Hamiltonian systems by application of skew-symmetric differential forms  

E-print Network

A great number of works is devoted to qualitative investigation of Hamiltonian systems. One of tools of such investigation is the method of skew-symmetric differential forms. In present work, under investigation Hamiltonian systems in addition to skew-symmetric exterior differential forms, skew-symmetric differential forms, which differ in their properties from exterior forms, are used. These are skew-symmetric differential forms defined on manifolds that are nondifferentiable ones. Such manifolds result, for example, under describing physical processes by differential equations. This approach to investigation of Hamiltonian systems enables one to understand a connection between Hamiltonian systems and partial differential equations, which describe physical processes, and to see peculiarities of Hamiltonian systems and relevant phase spaces connected with this fact.

L. I. Petrova

2005-03-14

140

Genetic Architecture of Skewed X Inactivation in the Laboratory Mouse  

PubMed Central

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

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

141

Use of fibre gratings for bit skew compensation in all optical bit parallel WDM systems  

Microsoft Academic Search

We demonstrate transmission of two wavelength division multiplexed (WDM) bit parallel channels over 100 km of standard single mode fibre link using direct-modulated laser diodes at 10 Gbit\\/s channel. Step-chirped fibre gratings are used to simultaneously compensate to bit skew and dispersion. Bit skew of approximately 2.5 ns due to the fibre dispersion is completely compensated. Our work show shows

M. E. Vieira Segatto; F. N. Timofeev; R. Wyatt; R. Kashyap; J. R. Taylor

2001-01-01

142

Signal skew aware floorplanning and bumper signal assignment technique for flip-chip  

Microsoft Academic Search

Flip-chip is a solution for designs requiring more I\\/O pins and higher speed. However, the higher speed demand also brings the issue of signal skew. In this paper, we propose a new 3-stage design layout methodology for flip-chip considering signal skew. Firstly, we produce an initial bumper signal assignment, and then solve the flip-chip floorplanning problem using a partitioning-based technique

Cheng-Yu Wang; Wai-Kei Mak

2009-01-01

143

Performance of skewed single-phase line-start permanent magnet motors  

Microsoft Academic Search

In this paper, the authors investigate the modeling of single-phase line-start permanent magnet motors using finite-element (FE) analysis. It is shown that FE modeling is capable of giving very accurate predictions when compared with test results, for both skewed and unskewed motors. The skewed motor is also modeled using an analytical method. The accuracy of the FE method is contrasted

Stephen Williamson; Andy M. Knight

1999-01-01

144

A study on the effects of a skewed distribution on the EWMA and MA charts  

NASA Astrophysics Data System (ADS)

The control chart is the most powerful tool in statistical process control. A control chart is a graphical display used to determine the presence of assignable causes so that prompt corrective actions can be taken to remove such causes before many nonconforming products are produced. The exponentially weighted moving average (EWMA) and moving average (MA) charts are very effective in detecting small and moderate shifts in the process mean. These two charts are constructed based on the properties of the normal distribution. In many practical applications, the validity of the normality assumption is always doubted as the process distribution could be skewed. A skewed distribution can result in a higher incidence of false alarms. This is due to the inconsistencies between the spread of a skewed distribution and the normality assumption employed in setting up a control chart. This paper studies the effects of a skewed distribution on the performances of the EWMA and MA charts, in terms of the charts' false alarm rates. We compare the in-control average run length (ARL0) performance of these two charts when the underlying distributions are normal and skewed. The gamma distribution is selected to represent the skewed distribution. A Monte Carlo simulation using the Statistical Analysis System (SAS) software is carried out to compute the necessary ARL0s. The findings of this study show that the ARL0 performance of the EWMA and MA charts is substantially affected by the skewed distribution. However, the MA chart is not as robust as the EWMA chart, in terms of the ARL0, when the distribution is skewed.

Liew, Jeng Young; Khoo, Michael Boon Chong; Neoh, Siang Gee

2014-07-01

145

Evolution of the derivative skewness for high-amplitude sound propagation.  

PubMed

The skewness of the first time derivative of a pressure waveform has been used as an indicator of shocks and nonlinearity in both rocket and jet noise data [e.g., Gee et al., J. Acoust. Soc. Am. 133, EL88-EL93 (2013)]. The skewness is the third central moment of the probability density function and demonstrates asymmetry of the distribution, e.g., a positive skewness may indicate large, infrequently occurring values in the data. In the case of nonlinearly propagating noise, a positive derivative skewness signifies occasional instances of large positive slope and more instances of negative slope as shocks form [Shepherd et al., J. Acoust. Soc. Am. 130, EL8-EL13 (2011)]. In this paper, the evolution of the derivative skewness, and its interpretation, is considered analytically using key solutions of the Burgers equation. This paper complements a study by Muhlestein et al. [J. Acoust. Soc. Am. 134, 3981 (2013)] that used similar methods but with a different metric. An analysis is performed to investigate the effect of a finite sampling frequency and additive noise. Plane-wave tube experiments and numerical simulations are used to verify the analytic solutions and investigate derivative skewness in random noise waveforms. [Work supported by ONR.]. PMID:25235925

Reichman, Brent O; Muhlestein, Michael B; Gee, Kent L; Neilsen, Tracianne B; Thomas, Derek C

2014-04-01

146

Short day lengths skew prenatal sex ratios toward males in Siberian hamsters.  

PubMed

For decades, researchers have documented significant skews in the production of male versus female offspring in many species. Because males and females are differentially susceptible to environmental challenges and also represent different fitness benefits, it may be beneficial to exert control over the offspring sex ratio when environmental conditions become challenging. Some of the most dramatic environmental challenges occur on a seasonal basis. Indeed, seasonal variation in offspring sex ratios has been documented in both mammalian and nonmammalian species. The seasonal environmental factor (or factors) that drives the skews in sex ratios is unknown; however, it is essential that such a cue be predictable and reliable and that it does not vary from year to year. We hypothesized that photoperiod, a stable cue of seasonal changes in temperature and resource availability, may underlie seasonal variation in offspring sex ratios of mammals. We predicted that short day lengths in particular, which signal impending winter conditions and related energetic demands, would stimulate an anticipatory skew in the offspring sex ratio. We used Siberian hamsters as models because they are phenotypically responsive to photoperiod but up to 60% of females continue to breed during the winter. The sexes of weanling hamsters conceived and raised in short, winter like day lengths were significantly skewed toward males. Furthermore, these skews occurred before birth; embryos collected from pregnant females maintained in short-day conditions were also significantly male biased. Thus, photoperiod functions as an effective seasonal cue, stimulating sex ratio skews toward males when day lengths are short. PMID:19938980

Navara, Kristen J; Workman, Joanna L; Oberdick, John; Nelson, Randy J

2010-01-01

147

Skewed X-chromosome inactivation in patients with esophageal carcinoma  

PubMed Central

Abstract Skewed X-chromosome inactivation (SXCI) was found in some apparently healthy females mainly from Western countries. It has been linked to development of ovarian, breast and pulmonary carcinomas. The present study aimed to observe the SXCI frequencies in apparently healthy Chinese females and patients with esophageal carcinoma. DNA was extracted from the peripheral blood cells from 401 Chinese females without a detectable tumor and 143 female patients with esophageal carcinoma. Exon 1 of androgen receptor (AR) gene was amplified, and the products of different CAG alleles were resolved on denaturing polyacrylamide gels and visualized after silver staining. The corrected ratios (CR) of the products before and after HpaII digestion were calculated. As to the healthy females, when CR???3 was used as a criterion, SXCI was found in two (4.3%) of the 46 neonates, 13 (7.8%) of the 166 younger adults (16–50 years) and 37 (25.7%) of the 144 elderly females (51–96 years), with the frequency higher in the elderly subjects than in the two former groups (P?

2013-01-01

148

Pennsylvania Covered Bridges  

NSDL National Science Digital Library

Covered bridges cause moments of delight for historic preservationists, and they entered a new place in American popular culture when they figured prominently in a certain Clint Eastwood film in the early 1990s. Recently, staff members and student assistants at Bucknell University spent a significant amount of time creating this digital collection of covered bridge photographs. Interestingly enough, the original photographs were taken by a long-time member of the biology faculty at Bucknell, one Professor Nelson F. Davis. The photos date from 1898 to 1939, and all told, there are over 300 images in this collection. Visitors will enjoy looking over this collection, and these documents will be of great interest to anyone fascinated by these types of bridges, engineering, or the history of rural Pennsylvania.

149

3. View northeast showing Kenyon Arch Bridge (Rhode Island Bridge ...  

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

3. View northeast showing Kenyon Arch Bridge (Rhode Island Bridge No. 148) over Pawcatuck River (foreground) and portion of Kenyon Industries mill complex (background). - Kenyon Village, Kenyon School Road, Sherman Avenue, & Lewiston Avenue, Richmond (historical), Providence County, RI

150

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

PubMed Central

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

2014-01-01

151

Static performance investigation of a skewed-throat multiaxis thrust-vectoring nozzle concept  

NASA Technical Reports Server (NTRS)

The static performance of a jet exhaust nozzle which achieves multiaxis thrust vectoring by physically skewing the geometric throat has been characterized in the static test facility of the 16-Foot Transonic Tunnel at NASA Langley Research Center. The nozzle has an asymmetric internal geometry defined by four surfaces: a convergent-divergent upper surface with its ridge perpendicular to the nozzle centerline, a convergent-divergent lower surface with its ridge skewed relative to the nozzle centerline, an outwardly deflected sidewall, and a straight sidewall. The primary goal of the concept is to provide efficient yaw thrust vectoring by forcing the sonic plane (nozzle throat) to form at a yaw angle defined by the skewed ridge of the lower surface contour. A secondary goal is to provide multiaxis thrust vectoring by combining the skewed-throat yaw-vectoring concept with upper and lower pitch flap deflections. The geometric parameters varied in this investigation included lower surface ridge skew angle, nozzle expansion ratio (divergence angle), aspect ratio, pitch flap deflection angle, and sidewall deflection angle. Nozzle pressure ratio was varied from 2 to a high of 11.5 for some configurations. The results of the investigation indicate that efficient, substantial multiaxis thrust vectoring was achieved by the skewed-throat nozzle concept. However, certain control surface deflections destabilized the internal flow field, which resulted in substantial shifts in the position and orientation of the sonic plane and had an adverse effect on thrust-vectoring and weight flow characteristics. By increasing the expansion ratio, the location of the sonic plane was stabilized. The asymmetric design resulted in interdependent pitch and yaw thrust vectoring as well as nonzero thrust-vector angles with undeflected control surfaces. By skewing the ridges of both the upper and lower surface contours, the interdependency between pitch and yaw thrust vectoring may be eliminated and the location of the sonic plane may be further stabilized.

Wing, David J.

1994-01-01

152

SBIR Phase II Bridge Award  

Cancer.gov

National Cancer Institute Bridging the Funding Gap for Promising Cancer Therapeutics, Imaging Technologies, Interventional Devices, Diagnostics, and Prognostics SBIR Phase II Bridge Award The National Cancer Institute (NCI) Small Business Innovation

153

The Bridge to Somewhere  

ERIC Educational Resources Information Center

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…

Lum, Lydia

2009-01-01

154

Building Migratory Bridges  

ERIC Educational Resources Information Center

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…

Roy, Michael; Doss, Laurie K.

2007-01-01

155

URI Student Bridge  

Microsoft Academic Search

The project that came to be known as URI Student Bridge began with my amazing college experience and my desire to share that experience with others who were making the decision of whether to begin a college experience of their own. I have been very fortunate to have the funding and motivation to attend college, and have had many opportunities

Nicole Aragi

2008-01-01

156

Bridging Disciplinary Boundaries  

ERIC Educational Resources Information Center

Interdisciplinary education promotes the unity of knowledge by bridging the cultural divide between the social constructs of disciplines and encourages the development of knowledge to enhance society. As an inquiry-based and relevant approach that expands and advances knowledge, interdisciplinary education facilitates creativity and flexibility,…

Mei, Linda

2009-01-01

157

Bridges link the world.  

PubMed

Organizations that use videoconferencing quickly discover how a video call connecting two sites can be a productive and cost effective way to hold meetings, offer remote diagnosis and participate in distance learning. But, administrative and education applications, in particular, are likely to require that multiple sites be networked at the same time. A simple solution is video bridging. PMID:10173298

Kaiser, F

1997-01-01

158

Semiconductor bridge (SCB) igniter  

Microsoft Academic Search

An explosive device is described comprising: a non electrically conducting substrate; an electrical material mounted on the substrate and having a negative temperature coefficient of electrical resistivity at an elevated temperature. The material covers an area of the substrate and defines a pair of spaced pads connected by a bridge; a metallized layer covering each of the spaced pads; an

R. W. Jr. Bickes; A. C. Schwartz

1987-01-01

159

Quantum bidding in Bridge  

E-print Network

Quantum methods allow to reduce communication complexity of some computational tasks, with several separated partners, beyond classical constraints. Nevertheless, experimental demonstrations of this fact are thus far 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 advantage in 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 specific form of communication, of a very low complexity (effectively one has a strong limitations on number of exchanged bits). Surprisingly, our quantum technique is not violating 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 (CHSH) game, which is equivalent to a $2\\to 1$ quantum random access code. Thus our experiment is also a realization of such protocols. However, this correspondence is not full which enables the Bridge players to have efficient strategies regardless of the quality of their detectors.

S. Muhammad; A. Tavakoli; M. Kurant; M. Pawlowski; M. Zukowski; M. Bourennane

2014-03-17

160

Bridging the Gap?  

ERIC Educational Resources Information Center

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…

Salter, Colin

2009-01-01

161

CMOS Bridging Fault Detection  

Microsoft Academic Search

The authors compare the performance of two test generation techniques, stuck fault testing and current testing, when applied to CMOS bridging faults. Accurate simulation of such faults mandated the development of several new design automation tools, including an analog-digital fault simulator. The results of this simulation are analyzed. It is shown that stuck fault test generation, while inherently incapable of

Thomas M. Storey; Wojciech Maly

1990-01-01

162

BUILDING BRIDGES IN HEALTHCARE  

Microsoft Academic Search

or those who have not been in the Charleston area for several years, 2005 has marked the opening of a fabulous new span that links Charleston with Mount Pleasant. In mid July, the entire region turned out to stroll over the new bridges and celebrate their completion with a monumental fireworks display. The two dilapidated structures that had offered an

Bill Hueston

163

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

PubMed Central

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

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

2008-01-01

164

A Guide to Covered Bridges  

NSDL National Science Digital Library

A Guide to Covered Bridges, offered by Drexel University, Philadelphia, Pennsylvania, transforms the Web into a time machine. Find the answer to the question, why are there so many covered bridges, and why in Pennsylvania and the Northeast? The Drexel University Honors Program sponsors this guide to dozens of covered bridges of the Philadelphia region. Driving tours are suggested, and bridge images are indexed by season (fall color, winter, snow and ice, spring/summer) and structure as well as county.

165

77 FR 16784 - General Bridge Regulation; Amendment  

Federal Register 2010, 2011, 2012, 2013

...USCG-2008-1188] RIN 1625-AB36 General Bridge Regulation; Amendment AGENCY: Coast...rulemaking concerning amendments to the general bridge regulations. The rulemaking was initiated...clarify the statutory responsibilities of bridge owners to remove their bridges from...

2012-03-22

166

Maintaining Minnesota's Unique Bridge Inventory  

E-print Network

Bridge revealed condition issues with the wire rope suspenders · A similar inspection of the Bong Bridge;Install New Suspender #12;Replace ­ New Hanger #12;Testing ­ Visual Inspection Areas of corrosion;Blatnik and Bong Bridges Wire Rope Replacement · In 2007, a fracture critical inspection of the Blatnik

Minnesota, University of

167

System reliability of suspension bridges  

Microsoft Academic Search

Provisions for the design of existing suspension bridges often rely on a deterministic basis. Consequently, the reliability of these bridges cannot be assessed if current provisions are applied. In order to develop cost-effective design and maintenance strategies for suspension bridges a system reliability-based approach has to be used. This is accomplished by a probabilistic finite element geometrically nonlinear analysis approach.

Kiyohiro Imai; Dan M. Frangopol

2002-01-01

168

Gaussian bridges Dario Gasbarra1  

E-print Network

Gaussian bridges Dario Gasbarra1 , Tommi Sottinen2 , and Esko Valkeila3 1 Department of Mathematics.valkeila@hut.fi Summary. We consider Gaussian bridges; in particular their dynamic representa- tions. We prove a Girsanov theorem between the law of Gaussian bridge and the original Gaussian process, which holds with natural

Sottinen, Tommi

169

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

PubMed Central

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

M?ller, Anders Pape; Bonisoli-Alquati, Andrea; Rudolfsen, Geir; Mousseau, Timothy A.

2012-01-01

170

Vehicle Impact in Box Girder Bridges and Bridge Substructures. Phase 1. Straight Box Girder Bridges.  

National Technical Information Service (NTIS)

This is the first part of the three-year project on vehicle impact in box girder bridges and bridge substructures. The objective of this investigation is to present a procedure for the study of the dynamic response of straight box girder bridges and to an...

D. Huang, T. L. Wang

1994-01-01

171

Molecular engineering with bridged polysilsesquioxanes  

SciTech Connect

Bridged polysilsesquioxanes are a class of hybrid organic-inorganic materials that permit molecular engineering of bulk properties including porosity. Prepared by sol-gel polymerization of monomers with two or more trialkoxysilyl groups, the materials are highly cross-linked amorphous polymers that are readily obtained as gels. The bridging configuration of the hydrocarbon group insures that network polymers are readily formed and that the organic functionality is homogeneously distributed throughout the polymeric scaffolding at the molecular level. This permits the bulk properties, including surface area, pore size, and dielectric constant to be engineered through the selection of the bridging organic group. Numerous bridging groups have been incorporated. This presentation will focus on the effects that the length, flexibility, and substitution geometry of the hydrocarbon bridging groups have on the properties of the resulting bridged polysilsesquioxanes. Details of the preparation, characterization, and some structure property relationships of these bridged polysilsesquioxanes will be given.

LOY,DOUGLAS A.; SHEA,KENNETH J.

2000-05-09

172

Electrical Actuation Technology Bridging  

NASA Astrophysics Data System (ADS)

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.

Hammond, Monica; Sharkey, John

1993-05-01

173

Bridge-NOAA Collection  

NSDL National Science Digital Library

The Bridge-NOAA Collection is a selection of exemplary resources from the National Oceanic and Atmospheric Administration (NOAA) that have been reviewed by educators and found to be well-suited for educational purposes. The collection also emphasizes professional-development opportunities for teachers. There is a strong focus on research data and its use in teaching. The collection provides educators with accurate and useful information on global, national, and regional ocean-science topics.

2007-10-19

174

Bridging the Gap  

NSDL National Science Digital Library

A newly appointed joint hire in the College of Arts and Sciences, Department of Natural Sciences and the College of Education, Department of Middle/Secondary Education, was charged with the responsibility of bridging the communication gap between these two departments and colleges. To meet this challenge, four collaborative projects were developed between the Natural Sciences faculty and Middle/Secondary Education science students that will become formally established in future university courses.

Eason, Grace

2004-11-01

175

Build a Bridge  

NSDL National Science Digital Library

In this activity, learners use recycled materials to build a bridge that holds as many potatoes as possible. They investigate weight, height, strength, and measurement as they seek design solutions. The activity instructions include ways to adjust the level of challenge for learners of different ages. Try this at family events or to engage all ages. Available as a web page and a downloadable PDF. Students should have the ability to use tape and scissors.

2010-01-01

176

BATS IN AMERICAN BRIDGES  

Microsoft Academic Search

Bridges and culverts were evaluated as bat roosting habitat in 25 U.S. states at elevations from sea level to 10,000 feet. Field surveys were conducted at 2,421 highway structures. Scientific literature was reviewed, and local biologists and engineers were interviewed, leading to the discovery of approximately 4,250,000 bats of 24 species living in 211 highway structures. Only one percent of

Brian W. Keeley; Merlin D. Tuttle

177

BRIDGE Other Resources  

NSDL National Science Digital Library

Bridge Ocean Resources provide access to ocean sciences educational materials with particular emphasis on K-12 audiences. The collection emphasizes biological oceanography, aquaria, research institutions, career information, student opportunities and announcements. There is a strong focus on research data and its use in teaching. The collection provides educators with a source of accurate and useful information on global, national, and regional ocean science topics, and gives researchers a contact point for educational outreach.

178

Fertility signalling and reproductive skew in queenless ants VIRGINIE CUVILLIER-HOT*, ALAIN LENOIR, ROBIN CREWE, CHRISTIAN MALOSSE & CHRISTIAN PEETERS*  

E-print Network

Fertility signalling and reproductive skew in queenless ants VIRGINIE CUVILLIER-HOT*, ALAIN LENOIR an extreme reproductive skew. In queenless ants, colonies consist of morphologically identical workers in these ants functions to select the reproductive(s). We investigated the mechanisms underlying reproductive

Danchin, Etienne

179

Study of Rolling Element Dynamic Interactions with Separator and Raceway Paths. Roller Skewing Measurements in Roller Bearings.  

National Technical Information Service (NTIS)

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 ...

L. J. Nypan

1980-01-01

180

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

E-print Network

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...

Rajaram, Anand K.

2004-11-15

181

Progress in understanding the renormalization group skewness and kappa-epsilon models  

NASA Technical Reports Server (NTRS)

The immediate goal is to understand and validate the Yakhot-Orszag model of the velocity-derivative skewness and model equation for the rate of energy dissipation epsilon. A summary of a more detailed manuscript in preparation is presented. The purpose is to clarify some limitations of the theory by careful examination of key assumptions and approximations, and thereby to encourage its improvement.

Smith, Leslie M.; Reynolds, W. C.

1991-01-01

182

A measure of sexual selection in hermaphroditic animals: parentage skew and the opportunity for selection  

E-print Network

A measure of sexual selection in hermaphroditic animals: parentage skew and the opportunity Introduction The role of sexual selection in hermaphroditic organisms was initially denied (Darwin, 1871), but research over the last decade has revealed that sexual selection oper- ates in hermaphrodites too (reviewed

Dever, Jennifer A.

183

Gamblers favor skewness, not risk: Further evidence from United States’ lottery games  

Microsoft Academic Search

Theoretical models of risk have attempted to explain why risk-averse individuals take unfair gambles. Using all United States’ lottery games, we find theoretical and empirical evidence that skewness of prize distributions explains why risk averse individuals may play the lottery.

Thomas A. Garrett; Russell S. Sobel

1999-01-01

184

On the Boundedness Property of the Inertia Matrix and Skew-Symmetric Property of the  

E-print Network

On the Boundedness Property of the Inertia Matrix and Skew-Symmetric Property of the Coriolis on the choice of state variables, the bound- edness of the inertia matrix will not necessarily hold. We show that deriving the dynamics in terms of quasi-velocities leads to an inertia matrix that is bounded in its

Gravdahl, Jan Tommy

185

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

E-print Network

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

McLachlan, Geoff

186

Large-Scale Age-Dependent Skewed Sex Ratio in a Sexually Dimorphic Avian Scavenger  

PubMed Central

Age-dependent skewed sex ratios have been observed in bird populations, with adult males generally outnumbering females. This trend is mainly driven by higher female mortality, sometimes associated with anthropogenic factors. Despite the large amount of work on bird sex ratios, research examining the spatial stability of adult sex ratios is extremely scarce. The Andean condor (Vultur gryphus) is the only bird of prey with strong sexual dimorphism favouring males (males are 30% heavier than females). By examining data from most of its South-American range, we show that while the juvenile sex ratio is balanced, or even female-skewed, the sex ratio becomes increasing male-skewed with age, with adult males outnumbering females by >20%, and, in some cases by four times more. This result is consistent across regions and independent of the nature of field data. Reasons for this are unknown but it can be hypothesized that the progressive disappearance of females may be associated with mortality caused by anthropogenic factors. This idea is supported by the asymmetric habitat use by the two sexes, with females scavenging in more humanized areas. Whatever the cause, male-skewed adult sex ratios imply that populations of this endangered scavenger face higher risks of extinction than previously believed. PMID:23029488

Lambertucci, Sergio A.; Carrete, Martina; Donazar, Jose Antonio; Hiraldo, Fernando

2012-01-01

187

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

PubMed

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

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

2014-08-22

188

Numerical investigation of the effect of inlet skew angle on the performance of mechanical vapor compressor  

Microsoft Academic Search

Mechanical vapor compressor is an essential component that governs the system performance and stability in the multi-effect desalination (MED) system. The importance of improving mechanical vapor compressor's compressing ability in enhancing the efficiency of multi-effect desalination (MED) system has been stressed for a long time. This study was aimed to investigate the influences of inlet skew angle of the impeller

Muhammad Nuim Labib; Seong Soo Kim; Duyoul Choi; Tony Utomo; Hanshik Chung; Hyomin Jeong

189

2FAR: A 2bcgskew Predictor Fused by an Alloyed Redundant History Skewed Perceptron Branch Predictor  

Microsoft Academic Search

This paper describes the 2bcgskew branch predictor fused by an alloyed redundant his- tory skewed perceptron predictor, which is our design submitted to the 1st JILP Champi- onship Branch Prediction (CBP) competition. The presented predictor intelligently com- bines multiple predictions (fusion) in order to obtain a more accurate prediction. The various predictions are delivered by a 2bcgskew predictor and include

Veerle Desmet; Hans Vandierendonck; Koen De Bosschere

190

Interval estimators for the population mean for skewed distributions with a small sample size  

E-print Network

Interval estimators for the population mean for skewed distributions with a small sample size Glen distributions with a small sample size SUMMARY In finite population sampling it has long been known on the `Polya posterior'. For large sample sizes these methods often closely mimic standard frequentist methods

Meeden, Glen

191

Skewness and Kurtosis as Applied to a Portfolio in the Korean Stock Market  

NASA Astrophysics Data System (ADS)

A well diversified portfolio is critical to prudent investment in a stock market. To lessen risk in a volatile market, portfolios should minimize dispersion. This paper analyzes skewness and kurtosis of businesses listed on Korean stock markets, e.g., KOSPI and KOSDAQ. It looks at distribution using the Gauss function, and examines how mean and variance can be applied in building a portfolio.

Ahn, Tae-Sung

2009-04-01

192

Effect of Data Skewness and Workload Balance in Parallel Data Mining  

E-print Network

Effect of Data Skewness and Workload Balance in Parallel Data Mining David W. Cheung, Member, IEEE an effective solution to this problem. In this paper, we study the behavior of parallel association rule mining, Sau D. Lee, and Yongqiao Xiao AbstractÐTo mine association rules efficiently, we have developed a new

Cheung, David Wai-lok

193

Modulation of root-skewing responses by KNAT1 in Arabidopsis thaliana.  

PubMed

The KNOTTED1 homeobox (KNOX) family transcription factors are essential for stem cell establishment and maintenance and regulate various aspects of development in all green plants. Expression patterns of the KNOX genes in the roots of plants have been reported, but their role in development remains unclear. Here we show how the KNAT1 gene is specifically involved in root skewing in Arabidopsis. The roots of two mutant alleles of KNAT1 (bp-1 and bp-5) exhibited exaggerated skewing to the right of gravity when grown on both vertical and tilted agar medium surfaces. This skewing phenotype was enhanced by treatments with low concentrations of propyzamide, and required auxin transport. The KNAT1 mutation substantially decreased basipetal auxin transport and increased auxin accumulation in the roots. Using a PIN2-GFP reporter and western blot analysis, we found that this alteration in auxin transport was accompanied by a decrease in PIN2 levels in the root tip. Decreased PIN2 expression in the mutant roots was not accompanied by reduced mRNA levels, suggesting that the KNAT1 mutations affected PIN2 expression at the posttranscriptional level. In vivo visualization of intracellular vacuolar targeting indicated that vacuolar degradation of PIN2-GFP was significantly promoted in the root tips of the bp allelic mutants. Together, these results demonstrate that KNAT1 negatively modulates root skewing, possibly by regulating auxin transport. PMID:23889705

Qi, Bin; Zheng, Huiqiong

2013-11-01

194

a Study of Recirculating Flow Computation Using Body-Fitted Coordinates: Consistency Aspects and Mesh Skewness  

Microsoft Academic Search

A study of the computation of recirculating flows using body-fitted coordinates has been conducted with a numerical algorithm developed previously. Both the consistent treatment of the continuity equation and the effects of the grid skewness on the calculated flow field have been investigated. A more consilient method has been developed that formally satisfies the conservation laws more closely, allowing the

M. Braaten; W. Shyy

1986-01-01

195

A study of recirculating flow computation using body-fitted coordinates - Consistency aspects and mesh skewness  

Microsoft Academic Search

A study of the computation of recirculating flows using body-fitted coordinates has been conducted with a numerical algorithm developed previously. Both the consistent treatment of the continuity equation and the effects of the grid skewness on the calculated flow field have been investigated. A more consistent method has been developed that formally satisfies the conservation laws more closely, allowing the

M. Braaten; W. Shyy

1986-01-01

196

Why Skewing Works: Learning Di#cult Boolean Functions with Greedy Tree Learners  

E-print Network

Why Skewing Works: Learning Di#cult Boolean Functions with Greedy Tree Learners Bernard Rosell to enable greedy decision tree learners to learn ``di#cult'' Boolean functions, such as parity, in the pres, such as parity, are di#cult for greedy decision tree learners to learn. These ``di#cult functions'' are such that

Ray, Soumya

197

WP9.06 Skew Detection and Compensation for Internet Audio Applications  

Microsoft Academic Search

Long lived audio streams, such as music broadcasts, and small differences in clock rates lead to buffer underflo w or overflo w events in receiving applications that manifest themselves as au- dible interruptions. We present a low complexity algorithm for detecting clock skew in network audio applications that function with local clocks and in the absence of a synchronization mech-

Orion Hodson; Colin Perkins; Vicky Hardman

2000-01-01

198

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

PubMed Central

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

Nash, Ulrik W.

2014-01-01

199

Short Day Lengths Skew Prenatal Sex Ratios Toward Males in Siberian Hamsters  

E-print Network

000 Short Day Lengths Skew Prenatal Sex Ratios Toward Males in Siberian Hamsters * Corresponding. Navara1, * Joanna L. Workman2 John Oberdick3,4 Randy J. Nelson2,3 1 Department of Poultry Science, 203 Poultry Science Building, University of Georgia, Athens, Georgia 30602; 2 Department of Psychology, Ohio

Navara, Kristen

200

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

NASA Astrophysics Data System (ADS)

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.

Dró?d?, Artur

2014-08-01

201

Parallel spinors and connections with skew-symmetric torsion in string theory  

Microsoft Academic Search

We describe all almost contact metric, almost hermitian and $G_2$-structures admitting a connection with totally skew-symmetric torsion tensor, and prove that there exists at most one such connection. We investigate its torsion form, its Ricci tensor, the Dirac operator and the $\\\

Thomas Friedrich; Stefan Ivanov

2001-01-01

202

Tacoma Narrows Bridge: Extreme History  

NSDL National Science Digital Library

Stretching across the southern portion of Puget Sound, the elegant Tacoma Narrows bridge is considered one of the finest suspension bridges in the United States. The current bridge is the second on the site, as it was constructed in 1950 to serve as a replacement to the famous "Galloping Gertie" bridge, which collapsed in a windstorm in the fall of 1940. Currently, the Washington State Department of Transportation is building a bridge to replace the existing structure, and it is anticipated that it will be completed in 2007. This site offers a host of materials on all three structures, including ample information on the construction of the bridges and their aesthetic appeal. Along with these materials, the site also provides a glossary of related terms, Weird Facts, and some information about the dog "Tubby", who perished when "Galloping Gertie" collapsed on that fateful fall day back in 1940.

203

Virtual Bridge Design  

NSDL National Science Digital Library

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 higher-level thinking skills and problem solving (NSTA 2006). It is important that we keep our students engaged in learning science, as the scientific society of tomorrow depends upon the science students of today.

Jeanpierre, Bobby; Bisogno, Janet

2008-09-01

204

West Point Bridge Design Contest  

NSDL National Science Digital Library

The second annual West Point Bridge Design Contest concluded in May 2003. Although it is uncertain whether the contest will receive funding for future competitions, its Web site has a number of educational resources for middle and high school students. The main feature is the bridge design software, which allows the user to "model, test, and optimize a steel highway bridge, based on realistic specifications, constraints, and performance criteria." Completed designs can be submitted online for unofficial judging. The book, Designing and Building File-Folder Bridges, can also be freely downloaded. This site is also reviewed in the July 4, 2003 NSDL MET Report.

2003-01-01

205

West Point Bridge Design Contest  

NSDL National Science Digital Library

The West Point Bridge Design Contest Web site has a number of educational resources for middle and high school students. The main feature is the bridge design software, which allows the user to "model, test, and optimize a steel highway bridge, based on realistic specifications, constraints, and performance criteria." Completed designs can be submitted online for unofficial judging. The book, Designing and Building File-Folder Bridges, can also be freely downloaded. This site is also reviewed in the July 4, 2003 NSDL MET Report.

2007-03-27

206

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

Code of Federal Regulations, 2012 CFR

...Telecommunication 5 2012-10-01 2012-10-01 false Bridge-to-bridge communication procedure. 80.331 Section 80...Alarm, Urgency and Safety Procedures § 80.331 Bridge-to-bridge communication procedure. (a)...

2012-10-01

207

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

Code of Federal Regulations, 2011 CFR

...Telecommunication 5 2011-10-01 2011-10-01 false Bridge-to-bridge radiotelephone installation. 80.1007 Section...SERVICES Radiotelephone Installations Required by the Bridge-to-Bridge Act § 80.1007...

2011-10-01

208

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

Code of Federal Regulations, 2013 CFR

...Telecommunication 5 2013-10-01 2013-10-01 false Bridge-to-bridge radiotelephone installation. 80.1007 Section...SERVICES Radiotelephone Installations Required by the Bridge-to-Bridge Act § 80.1007...

2013-10-01

209

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

Code of Federal Regulations, 2013 CFR

...Telecommunication 5 2013-10-01 2013-10-01 false Bridge-to-bridge communication procedure. 80.331 Section 80...Alarm, Urgency and Safety Procedures § 80.331 Bridge-to-bridge communication procedure. (a)...

2013-10-01

210

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

Code of Federal Regulations, 2012 CFR

...Telecommunication 5 2012-10-01 2012-10-01 false Bridge-to-bridge radiotelephone installation. 80.1007 Section...SERVICES Radiotelephone Installations Required by the Bridge-to-Bridge Act § 80.1007...

2012-10-01

211

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

Code of Federal Regulations, 2010 CFR

...Telecommunication 5 2010-10-01 2010-10-01 false Bridge-to-bridge radiotelephone installation. 80.1007 Section...SERVICES Radiotelephone Installations Required by the Bridge-to-Bridge Act § 80.1007...

2010-10-01

212

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

Code of Federal Regulations, 2010 CFR

...Telecommunication 5 2010-10-01 2010-10-01 false Bridge-to-bridge communication procedure. 80.331 Section 80...Alarm, Urgency and Safety Procedures § 80.331 Bridge-to-bridge communication procedure. (a)...

2010-10-01

213

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

Code of Federal Regulations, 2011 CFR

...Telecommunication 5 2011-10-01 2011-10-01 false Bridge-to-bridge communication procedure. 80.331 Section 80...Alarm, Urgency and Safety Procedures § 80.331 Bridge-to-bridge communication procedure. (a)...

2011-10-01

214

Extended bridge algorithms for large networks  

Microsoft Academic Search

A network bridge is a device that operates at the ISO data link level and routes packets across extended networks, commonly composed of multiple local area networks (LANs) and bridges. A set of algorithms that greatly extends the application of the network bridge is presented. This multitree bridge algorithm allows networks of arbitrary topology and capacity to use bridge routing.

W. D. Sincoskie; C. J. Cotton

1988-01-01

215

Toward Quantifying the Spreading-Rate Dependence of Anomalous Skewness of Marine Magnetic Anomalies due to Seafloor Spreading  

NASA Astrophysics Data System (ADS)

In past work, reliable paleomagnetic poles have been determined from skewness data by solving for a single additional adjustable parameter, anomalous skewness, assumed to be independent of spreading rate [Petronotis et al. 1992, 1994; Petronotis & Gordon 1999]. Nonetheless, analysis of anomalies in several ocean basins indicate that anomalous skewness depends on spreading rate for spreading half rates less than ?50 mm/yr [Roest et al., 1992; Dyment et al. 1994]. To facilitate investigation of the influence of spreading-rate dependent anomalous skewness on the determination of paleomagnetic poles determined from skewness, we build on the model for marine magnetic anomalies due to seafloor spreading of Dyment and Arkani-Hamed [1995]. We use this model to estimate anomalous skewness as a function of spreading rate for many anomalies. Synthetic magnetic anomaly profiles for oceanic lithosphere with sloping curving reversal boundaries were produced by forward modeling. Anomalous skewness values for chrons 25n to 33r were visually determined at various spreading rates using two approaches: balancing the shoulders of an anomaly corresponding to a single chron and best matching an anomaly corresponding to a single chron to a synthetic anomaly determined assuming vertical reversal boundaries. The new results may facilitate the determination of paleomagnetic poles from less widely distributed crossings of a magnetic anomaly than were used before. Further implications for determination of paleomagnetic poles for the Pacific plate will be discussed.

Boswell, S. M.; Zheng, L.; Gordon, R. G.; Dyment, J.

2010-12-01

216

Quantifying reinforced concrete bridge deck deterioration using ground penetrating radar  

NASA Astrophysics Data System (ADS)

Bridge decks are deteriorating at an alarming rate due to corrosion of the reinforcing steel, requiring billions of dollars to repair and replace them. Furthermore, the techniques used to assess the decks don't provide enough quantitative information. In recent years, ground penetrating radar (GPR) has been used to quantify deterioration by comparing the rebar reflection amplitudes to technologies serving as ground truth, because there is not an available amplitude threshold to distinguish healthy from corroded areas using only GPR. The goal of this research is to understand the relationship between GPR and deck deterioration, and develop a model to determine deterioration quantities with GPR alone. The beginning of this research determines that not only is the relationship between GPR and rebar corrosion stronger than the relationship between GPR and delaminations, but that the two are exceptionally correlated (90.2% and 86.6%). Next, multiple bridge decks were assessed with GPR and half-cell potential (HCP). Statistical parameters like the mean and skewness were computed for the GPR amplitudes of each deck, and coupled with actual corrosion quantities based on the HCP measurements to form a future bridge deck model that can be used to assess any deck with GPR alone. Finally, in order to understand exactly which component of rebar corrosion (rust, cracking or chloride) attenuates the GPR data, computational modeling was carried out to isolate each variable. The results indicate that chloride is the major contributor to the rebar reflection attenuation, and that computational modeling can be used to accurately simulate GPR attenuation due to chloride.

Martino, Nicole Marie

217

WILLIAM B. BRIDGES INTERVIEWED BY  

E-print Network

WILLIAM B. BRIDGES (1934 ­ ) INTERVIEWED BY SHIRLEY K. COHEN May ­ June 2001, March 2004 Photo, and an Addendum, March 2004, with William B. Bridges, Carl F. Braun Professor of Engineering in the Division, and GTE. Concludes the interview with his recollections of Caltech President Marvin L. (Murph) Goldberger

Low, Steven H.

218

Mathematical models of suspension bridges  

Microsoft Academic Search

In this work we try to explain various mathematical models describing the dynamical behaviour of suspension bridges such as the Tacoma Narrows bridge. Our attention is concentrated on the derivation of these models, an interpretation of particular parameters and on a discussion of their advantages and disadvantages. Our work should be a starting point for a qualitative study of dynamical

Gabriela Taj?ová

1997-01-01

219

Mathematics in Use: Suspension Bridges.  

ERIC Educational Resources Information Center

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…

Ginther, John L.

1992-01-01

220

Toni Rttimann Bridges for people  

E-print Network

Toni Rüttimann Bridges for people 1 March 2013 Politecnico di Milano - Campus Bovisa­ aula BL2701 personal effects, the second one for his suspension bridgebuilding. Toni helps the more destitute people to build or re-build their own bridges, often after a hurricane, an earthquake, a war event. The story

221

Causes of Bridge Pier Staining.  

National Technical Information Service (NTIS)

Four types of bridge stains exist in Arkansas: Rust stains - those stains directly traceable to rust; red stains - broad stains which are not directly traceable to rust; gray stains - similar to red stains except for color; and graffiti. Bridge stains in ...

S. I. Thornton, C. Springer

1974-01-01

222

Halliburton Composite Bridge Plug Assembly  

Microsoft Academic Search

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

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

2005-01-01

223

Trigenomic Bridges for Brassica Improvement  

Microsoft Academic Search

We introduce and review Brassica crop improvement via trigenomic bridges. Six economically important Brassica species share three major genomes (A, B, and C), which are arranged in diploid (AA, BB, and CC) and allotetraploid (AABB, AACC, and BBCC) species in the classical triangle of U. Trigenomic bridges are Brassica interspecific hybrid plants that contain the three genomes in various combinations,

Sheng Chen; Matthew N. Nelson; Anne-Marie Chèvre; Eric Jenczewski; Zaiyun Li; Annaliese S. Mason; Jinling Meng; Julie A. Plummer; Aneeta Pradhan; Kadambot H. M. Siddique; Rod J. Snowdon; Guijun Yan; Weijun Zhou; Wallace A. Cowling

2011-01-01

224

75 FR 41281 - Bridge Safety Standards  

Federal Register 2010, 2011, 2012, 2013

...sudden damage from severe weather conditions or heavy water...all available design and modification documents and current reports...other purposes. Bridge modification and bridge repair. ``Bridge modification'' means a change to...

2010-07-15

225

33 CFR 115.40 - Bridge repairs.  

Code of Federal Regulations, 2012 CFR

...Waters 1 2012-07-01 2012-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE...

2012-07-01

226

33 CFR 115.40 - Bridge repairs.  

Code of Federal Regulations, 2010 CFR

...Waters 1 2010-07-01 2010-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE...

2010-07-01

227

49 CFR 236.713 - Bridge, movable.  

Code of Federal Regulations, 2010 CFR

...Transportation 4 2010-10-01 2010-10-01 false Bridge, movable. 236.713 Section 236.713 Transportation...SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.713 Bridge, movable. That section of a structure bridging a...

2010-10-01

228

33 CFR 115.40 - Bridge repairs.  

Code of Federal Regulations, 2013 CFR

...Waters 1 2013-07-01 2013-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE...

2013-07-01

229

33 CFR 115.40 - Bridge repairs.  

Code of Federal Regulations, 2011 CFR

...Waters 1 2011-07-01 2011-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE...

2011-07-01

230

Bridge Building: Art and Science  

NSDL National Science Digital Library

This site is one of the most substantial, comprehensive sources on the Internet dedicated to bridge design and history. It has an incredible list of sections from which to choose, and each describes a particular bridge type or characteristic. Several pictures are included from all over the world that give examples of arch, truss, suspension, and many other bridge designs. There are also explanations of forces that act upon bridges, as well as what issues are considered when choosing the kind of bridge to build over a span. Perhaps the only drawback to the site is that there is so much information; the main page seems a bit cluttered. However, it does not really hamper navigating the site.

231

Burning trees and bridges  

NASA Technical Reports Server (NTRS)

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.

Levine, Joel S.

1990-01-01

232

Stanford: The Bridge Project  

NSDL National Science Digital Library

Stanford University's Bridge Project: Strengthening K-16 Transition Policies emphasizes that "reforms affecting K-12 and higher education must occur across systems in order to achieve the desired outcomes." Their approach is to improve opportunities for all students to enter and succeed in higher education by strengthening the alignment between higher education admissions-related requirements and K-12 curriculum frameworks, standards, and assessments. They conduct research that is meant to inform educational institutions and federal, state, and local agencies through descriptive analysis of the policies, identification of "disjunctures that exist in the current policy environment," and recommendations for improving the current system. Details about this program as well as their policy reports and briefs are available from their website.

233

The Bridges Organization  

NSDL National Science Digital Library

The connection between art and mathematics is well known, and the Bridges Organization has been bringing together these two worlds since 1998. The group started in Kansas, and since then they have traveled to cities in North America and Europe. On this site, visitors can learn about their past conferences, and view some of their galleries of images. The "Virtual Museum" area is a real treat, and visitors can look at spherical paintings, geometric sculptures, and algorithmic visual art. Moving on, the "Educational Resource Center" area features links of interest to educators, including sites dedicated to teaching mathematical thinking through origami and such. The site is rounded out by past conference reports and information about their leadership.

234

Bridges to Structure  

NSDL National Science Digital Library

This project's goals are to investigate structural components at a variety of levels: molecularly, cellularlly (histologically),phylogenetically, organismally, etc. Traditionally the stuctural classes at many institutions have used primarily dissection and histology for comparison of different vertebrate classes. In this project, we began to develop exercises at the molecular level using gemonmic and proteomic information to form phylogenetic trees, started a chart of materials available at NCBI for use in comparison (phylogentically and visually) of characteristic proteins from specific organ systems, and initiated thinking about a project to start a pictorial archive of dissection activities and histological meassurements. With the signifcant movement to integrate more material within biology and other areas of science and mathematics, building bridges (exercises) amongst a number of levels seems relevant. In addition, adding more open-ended projects with greater manipulation of data and mathematical manipulation in these courses is very desirable.

Peter Woodruff (Champlain-St. Lambert College;); Joyce Cadawallader (Saint-Mary-of-the-Woods College;)

2004-06-12

235

Semiconductor Bridge Cable Test  

SciTech Connect

The semiconductor bridge (SCB) is an electroexplosive device used to initiate detonators. A C cable is commonly used to connect the SCB to a firing set. A series of tests were performed to identify smaller, lighter cables for firing single and multiple SCBs. This report provides a description of these tests and their results. It was demonstrated that lower threshold voltages and faster firing times can be achieved by increasing the wire size, which reduces ohmic losses. The RF 100 appears to be a reasonable substitute for C cable when firing single SCBs. This would reduce the cable volume by 68% and the weight by 67% while increasing the threshold voltage by only 22%. In general, RG 58 outperforms twisted pair when firing multiple SCBs in parallel. The RG 58's superior performance is attributed to its larger conductor size.

KING, TONY L.

2002-01-01

236

Myeloid skewing in murine autoimmune arthritis occurs in hematopoietic stem and primitive progenitor cells  

PubMed Central

Skewing toward myeloid cell production is often observed in chronic inflammation and autoimmune diseases. Herein, we determined whether persistent myeloid activation and proinflammatory output occurring in pathologic conditions is at the level of hematopoietic stem and primitive progenitor cells (HSPPCs). By using a mouse arthritis model, we found that even though HSPPCs in arthritis still retained the capacity to differentiate into different lineages, they acquired enhanced in vitro and in vivo propensity in a disease-dependent manner to generate myeloid cells, the key perpetrators of tissue damage in arthritis. This myeloid skewing was cell intrinsic, as arthritic HSPPCs up-regulate myeloid-specific transcripts including S100a8. Exogenous S100a8 promoted myeloid cell output from wild-type HSPPCs, suggesting mechanistic involvement of this gene in the myeloid priming that occurs in arthritic HSPPCs. Therefore, our results indicate that in arthritic mice, HSPPCs adopt a pathologic state that favors disease persistence. PMID:22855602

Oduro, Kwadwo A.; Liu, Fang; Tan, Qing; Kim, Chan-Kyu; Lubman, Olga; Fremont, Daved; Mills, Jason C.

2012-01-01

237

Weighted skewness and kurtosis unbiased by sample size and Gaussian uncertainties  

E-print Network

Central moments and cumulants are often employed to characterize the distribution of data. The skewness and kurtosis are particularly useful for the detection of outliers, the assessment of departures from normally distributed data, automated classification techniques and other applications. Robust definitions of higher order moments are more stable but might miss characteristic features of the data, as in the case of astronomical time series with rare events like stellar bursts or eclipses from binary systems. Weighting can help identify reliable measurements from uncertain or spurious outliers, so unbiased estimates of the weighted skewness and kurtosis moments and cumulants, corrected for sample-size biases, are provided under the assumption of independent data. The comparison of biased and unbiased weighted estimators is illustrated with simulations as a function of sample size, employing different data distributions and weighting schemes.

Rimoldini, Lorenzo

2014-01-01

238

Maneuver planning of a rigid spacecraft with two skew control moment gyros  

NASA Astrophysics Data System (ADS)

The attitude maneuver planning of a rigid spacecraft using two skew single-gimbal control moment gyros (CMGs) is investigated. First, two types of restrictions are enforced on the gimbal motions of two skew CMGs, with each restriction yielding continuous control torque along a principal axis of the spacecraft. Then, it is proved that any axis fixed to the spacecraft can be pointed along an arbitrary inertial direction by at most two sequent rotations around the two actuated axes. Given this fact, a two-step eigenaxis rotation strategy, executing by the two single-axis torques respectively, is designed to point a given body-fixed axis along a desired direction. Furthermore, a three-step eigenaxis rotation strategy is constructed to achieve an arbitrary rest-to-rest attitude maneuver. The rotation angles required for the single-axis pointing and arbitrary attitude maneuver schemes are all analytically solved. Numerical examples are presented to demonstrate the effectiveness of the proposed algorithms.

Gui, Haichao; Jin, Lei; Xu, Shijie

2014-11-01

239

Symmetric and skew-symmetric weight functions in perturbation models of 2D interfacial cracks  

E-print Network

In this paper we address the vector problem of a 2D interfacial crack loaded by a general asymmetric distribution of forces acting on its faces. It is shown that the general integral formula for the evaluation of stress intensity factors, as well as high-order terms, requires both symmetric and skew-symmetric weight function matrices. The symmetric weight function matrix is obtained via the solution of a Wiener-Hopf functional equation, whereas the derivation of the skew-symmetric weight function matrix requires the construction of the corresponding full field singular solution. The weight function matrices are then used in the perturbation analysis of a crack advancing quasi-statically along the interface between two dissimilar media. A general and rigorous asymptotic procedure is developed to compute the perturbations of stress intensity factors as well as high-order terms.

Piccolroaz, A; Movchan, A B

2008-01-01

240

Symmetric and skew-symmetric weight functions in perturbation models of 2D interfacial cracks  

E-print Network

In this paper we address the vector problem of a 2D half-plane interfacial crack loaded by a general asymmetric distribution of forces acting on its faces. It is shown that the general integral formula for the evaluation of stress intensity factors, as well as high-order terms, requires both symmetric and skew-symmetric weight function matrices. The symmetric weight function matrix is obtained via the solution of a Wiener-Hopf functional equation, whereas the derivation of the skew-symmetric weight function matrix requires the construction of the corresponding full field singular solution. The weight function matrices are then used in the perturbation analysis of a crack advancing quasi-statically along the interface between two dissimilar media. A general and rigorous asymptotic procedure is developed to compute the perturbations of stress intensity factors as well as high-order terms.

A. Piccolroaz; G. Mishuris; A. B. Movchan

2008-12-24

241

Dual-Sampling Skewed CMOS Design for Soft-Error Tolerance  

Microsoft Academic Search

Presented is a circuit technique that mitigates the impact of single-event transient (SET) in deep submicrometer circuits with minimal speed, power, and area penalty. The technique combines a novel dual-sampling flip-flop (DSFF) and the skewed CMOS (SCMOS) circuit style. The DSFF and SCMOS are designed to eliminate SETs with the polarity of 1rarr0 and 0rarr1, respectively. We study inverter chain

Ming Zhang; Naresh R. Shanbhag

2006-01-01

242

Design and testing of a redundant skewed inertial sensor complex for integrated navigation and flight control  

NASA Technical Reports Server (NTRS)

Requirements for a redundant strapdown inertial sensor complex applied to V/STOL aircraft as developed by NASA are presented. Flight test data of a redundant, skewed axis strapdown inertial system are given, demonstrating the feasibility of the primary design aspects. This data consisted of parity equation responses through various flight conditions, showing residual noise levels on redundant gyro and accelerometer comparisons as a measure of minimum failure-level detectability, plus failure isolation and navigation performance through several simulated instrument failures.

Ebner, R. E.; Howell, W. E.

1979-01-01

243

Skewed X-chromosome inactivation is common in fetuses or newborns associated with confined placental mosaicism.  

PubMed

The inactivation of one X chromosome in females is normally random with regard to which X is inactivated. However, exclusive or almost-exclusive inactivation of one X may be observed in association with some X-autosomal rearrangements, mutations of the XIST gene, certain X-linked diseases, and MZ twinning. In the present study, a methylation difference near a polymorphism in the X-linked androgen-receptor gene was used to investigate the possibility that nonrandom X inactivation is increases in fetuses and newborns that are associated with confined placental mosaicism (CPM) involving an autosomal trisomy. Extreme skewing was observed in 7 (58%) of 12 cases with a meiotic origin of the trisomy, but in none of 10 cases examined with a somatic origin of the trisomy, and in only 1 (4%) of 27 control adult females. In addition, an extremely skewed X-inactivation pattern was observed in 3 of 10 informative cases of female uniparental disomy (UPD) of chromosome 15. This may reflect the fact that a proportion of UPD cases arise by "rescue" of a chromosomally abnormal conceptus and are therefore associated with CPM. A skewed pattern of X inactivation in CPM cases is hypothesized to result from a reduction in the size of the early-embryonic cell pool, because of either poor early growth or subsequent selection against the trisomic cells. Since approximately 2% of pregnancies detected by chorionic villus sampling are associated with CPM, this is likely a significant contributor to both skewed X inactivation observed in the newborn population and the expression of recessive X-linked diseases in females. PMID:9399909

Lau, A W; Brown, C J; Peñaherrera, M; Langlois, S; Kalousek, D K; Robinson, W P

1997-12-01

244

Assessment of mechanism of acquired skewed X inactivation by analysis of twins  

Microsoft Academic Search

Skewed X-chromosome inactivation in pe- ripheral blood granulocytes becomes more frequent with increasing age, affect- ing up to half of those over 75 years old. To investigate the mechanisms underly- ing this phenomenon, X-inactivation pro- files in 33 monozygotic and 22 dizygotic elderly twin pairs were studied. Differen- tial methylation-sensitive restriction en- zyme cutting at a hypervariable locus in the

Mark A. Vickers; Ewan McLeod; Timothy D. Spector; Ian J. Wilson

2001-01-01

245

A method of reducing ripple torque in permanent magnet motors without skewing  

Microsoft Academic Search

A method of reducing ripple torque, i.e., the sum of cogging and commutation torques, in permanent-magnet motors without skewing is proposed. The ripple torque for a given range of stator current can be substantially reduced by shifting the pole pairs by half a slot pitch and by choosing the value of magnet width so as to minimize the second-order component

T. Ishikawa; G. R. Slemon

1993-01-01

246

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

SciTech Connect

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.

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

2011-07-05

247

Vertical-Velocity Skewness in the Buoyancy-Driven Boundary Layer  

Microsoft Academic Search

A number of puzzling features of the skewness of the vertical velocity field, Sw(z), are found in observations and large-eddy simulations (LES) of the buoyancy-driven planetary boundary layer (PBL). For example, observations of Sw(z) in cases where the air is heated from below indicate that Sw(z) > 0 and remains relatively constant for z 0.3zi, whereas all large-eddy simulations of

Chin-Hoh Moeng; Richard Rotunno

1990-01-01

248

Skewed X-chromosome inactivation is common in fetuses or newborns associated with confined placental mosaicism.  

PubMed Central

The inactivation of one X chromosome in females is normally random with regard to which X is inactivated. However, exclusive or almost-exclusive inactivation of one X may be observed in association with some X-autosomal rearrangements, mutations of the XIST gene, certain X-linked diseases, and MZ twinning. In the present study, a methylation difference near a polymorphism in the X-linked androgen-receptor gene was used to investigate the possibility that nonrandom X inactivation is increases in fetuses and newborns that are associated with confined placental mosaicism (CPM) involving an autosomal trisomy. Extreme skewing was observed in 7 (58%) of 12 cases with a meiotic origin of the trisomy, but in none of 10 cases examined with a somatic origin of the trisomy, and in only 1 (4%) of 27 control adult females. In addition, an extremely skewed X-inactivation pattern was observed in 3 of 10 informative cases of female uniparental disomy (UPD) of chromosome 15. This may reflect the fact that a proportion of UPD cases arise by "rescue" of a chromosomally abnormal conceptus and are therefore associated with CPM. A skewed pattern of X inactivation in CPM cases is hypothesized to result from a reduction in the size of the early-embryonic cell pool, because of either poor early growth or subsequent selection against the trisomic cells. Since approximately 2% of pregnancies detected by chorionic villus sampling are associated with CPM, this is likely a significant contributor to both skewed X inactivation observed in the newborn population and the expression of recessive X-linked diseases in females. Images Figure 1 PMID:9399909

Lau, A W; Brown, C J; Penaherrera, M; Langlois, S; Kalousek, D K; Robinson, W P

1997-01-01

249

ROCS: Receiver Operating Characteristic Surface for Class-Skewed High-Throughput Data  

Microsoft Academic Search

The receiver operating characteristic (ROC) curve is an important tool to gauge the performance of classifiers. In certain situations of high-throughput data analysis, the data is heavily class-skewed, i.e. most features tested belong to the true negative class. In such cases, only a small portion of the ROC curve is relevant in practical terms, rendering the ROC curve and its

Tianwei Yu

2012-01-01

250

Measuring skewness of red blood cell deformability distribution by laser ektacytometry  

NASA Astrophysics Data System (ADS)

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.

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

2014-08-01

251

Dynamics Regulation of a Skew Cantilever Plate Using PZT Patches and Saturation Phenomenon  

Microsoft Academic Search

We investigate the suppression of steady-state vibrations of a cantilevered skew aluminum plate using nonlinear saturation phenomena and PZT (lead zirconate titanate) patches. Finite-element analysis and measurement of operational deflection shapes using a scanning laser vibrometer are performed to study the bending-torsional dynamic characteristics of the plate due to non-rectangular geometry. The control method uses linear second-order controllers coupled to

P. Frank Pai; Bernd Rommel; Mark J. Schulz

2000-01-01

252

Skew of Mononucleotide Frequencies, Relative Abundance of Dinucleotides, and DNA Strand Asymmetry  

Microsoft Academic Search

.   Based on 152 mitochondrial genomes and 36 bacterial chromosomes that have been completely sequenced, as well as three long\\u000a contigs for human chromosomes 6, 21, and 22, we examined skews of mononucleotide frequencies and the relative abundance of\\u000a dinucleotides in one DNA strand. Each group of these genomes has its own characteristics. Regarding mitochondrial genomes,\\u000a both CpG and GpT

Chiharu Shioiri; Naoyuki Takahata

2001-01-01

253

Reproductive partitioning and the assumptions of reproductive skew models in the cooperatively breeding American crow.  

PubMed

Understanding the benefits of cooperative breeding for group members of different social and demographic classes requires knowledge of their reproductive partitioning and genetic relatedness. From 2004-2007, we examined parentage as a function of relatedness and social interactions among members of 21 American crow (Corvus brachyrhynchos) family groups. Paired female breeders monopolized maternity of all offspring in their broods, whereas paired male breeders sired 82.7% of offspring, within-group auxiliary males sired 6.9% of offspring, and extragroup males sired 10.4% of offspring. Although adult females had fewer opportunities for direct reproduction as auxiliaries than males, they appeared to have earlier opportunities for independent breeding. These different opportunities for direct reproduction probably contributed to the male biased adult auxiliary sex ratio. Patterns of reproductive partitioning and conflict among males were most consistent with a synthetic reproductive skew model, in which auxiliaries struggled with breeders for a limited reproductive share, beyond which breeders could evict them. Counter to a frequent assumption of reproductive skew models, female breeders appeared to influence paternity, although their interests might have agreed with the interests of their paired males. Unusual among cooperative breeders, close inbreeding and incest occurred in this population. Incest avoidance between potential breeders did not significantly affect reproductive skew. PMID:20126287

Townsend, Andrea K; Clark, Anne B; McGowan, Kevin J; Lovette, Irby J

2009-02-01

254

Skew-symmetric forms: On integrability of equations of mathematical physics  

E-print Network

The study of integrability of the mathematical physics equations showed that the differential equations describing real processes are not integrable without additional conditions. This follows from the functional relation that is derived from these equations. Such a relation connects the differential of state functional and the skew-symmetric form. This relation proves to be nonidentical, and this fact points to the nonintegrability of the equations. In this case a solution to the equations is a functional, which depends on the commutator of skew-symmetric form that appears to be unclosed. However, under realization of the conditions of degenerate transformations, from the nonidentical relation it follows the identical one on some structure. This points out to the local integrability and realization of a generalized solution. In doing so, in addition to the exterior forms, the skew-symmetric forms, which, in contrast to exterior forms, are defined on nonintegrable manifolds (such as tangent manifolds of differential equations, Lagrangian manifolds and so on), were used. In the present paper, the partial differential equations, which describe any processes, the systems of differential equations of mechanics and physics of continuous medium and field theory equations are analyzed.

L. I. Petrova

2009-10-30

255

Free vibration of composite skewed cylindrical shell panel by finite element method  

NASA Astrophysics Data System (ADS)

In this paper a composite triangular shallow shell element has been used for free vibration analysis of laminated composite skewed cylindrical shell panels. In the present element first-order shear deformation theory has been incorporated by taking transverse displacement and bending rotations as independent field variables. The interpolation function used to approximate transverse displacement is one order higher than for bending rotations. This has made the element free from locking in shear. Two types of mass lumping schemes have been recommended. In one of the mass lumping scheme the effect of rotary inertia has been incorporated in the element formulations. Free vibration of skewed composite cylindrical shell panels having different thickness to radius ratios ( h/R=0.01-0.2), length to radius ratios ( L/R), number of layers and fiber orientation angles have been analyzed following the shallow shell method. The results for few examples obtained in the present analysis have compared with the published results. Some new results of composite skewed cylindrical shell panels have been presented which are expected to be useful to future research in this direction.

Haldar, Salil

2008-03-01

256

arXiv:0902.1795v2[math.AG]19Nov2009 CATEGORICAL GEOMETRIC SKEW HOWE DUALITY  

E-print Network

arXiv:0902.1795v2[math.AG]19Nov2009 CATEGORICAL GEOMETRIC SKEW HOWE DUALITY SABIN CAUTIS, JOEL;2 SABIN CAUTIS, JOEL KAMNITZER, AND ANTHONY LICATA 1. Introduction This paper is part of the program laid

Cautis, Sabin

257

Chesapeake Bay Bridge-Tunnel  

NSDL National Science Digital Library

The Chesapeake Bay Bridge-Tunnel is a 20 mile long series of bridges and tunnels that connect Virginia Beach/Norfolk to Virginia's Eastern Shore. The project is an engineering marvel; besides supporting vehicular traffic, the tunnels allow sea-going vessels passage into and out of the bay. A great deal of information is given on the project's home page, including a map of the surrounding area, historical perspectives, interesting facts, tourist attractions, and frequently asked questions. There are also a few pictures scattered throughout the site that show the enormity of the bridge-tunnel.

2002-01-01

258

Representation of skew in time-stepped two-dimensional finite-element models of electrical machines  

Microsoft Academic Search

The authors outline a technique which enables two-dimensional finite-element analysis to be applied to skewed machines. It involves representing the continuous skewing in a series of discrete steps. Each step may be modeled in two dimensions. The model has been applied to a salient-pole synchronous generator and to a cage induction motor. It is shown that the model is successful

Stephen Williamson; Timothy J. Flack; Albertus F. Volschenk

1995-01-01

259

The Higgs Bridge  

E-print Network

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.

Roland E. Allen

2013-11-11

260

Mineral bridges in nacre revisited  

E-print Network

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 (< 60 nm), earlier reported to be mineral bridges, found to be such.

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

2012-07-20

261

Mineral bridges in nacre revisited  

E-print Network

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 (< 60 nm), earlier reported to be mineral bridges, found to be such.

Checa, Antonio G; Willinger, Marc-Georg

2012-01-01

262

SURROGATE BRIDGE FREEZING SRDJAN JANKOVIC  

E-print Network

for advanced bridge deck heating control strategies. In order to develop the "smart" control system, some data Department of Transportation and the Federal Highway Administration for funding this project. I also extend

263

Bridges, Switches, Routers 1.1 Introduction  

E-print Network

Chapter 1 Bridges, Switches, Routers 1.1 Introduction ¯ Packet vs circuit (and virtual circuit ¯ Packet processors--Bridges, Routers, ATM switches 1 #12;2 CHAPTER 1. BRIDGES, SWITCHES, ROUTERS Routing in an extended LAN. See Problem 2. #12;4 CHAPTER 1. BRIDGES, SWITCHES, ROUTERS Figure 1.3: LAN vs VLAN topology

Varaiya, Pravin

264

Geology Fieldnotes: Natural Bridges National Monument, Utah  

NSDL National Science Digital Library

This site describes how natural bridges form in crossbedded sandstone, the three stages of bridge maturity, and the differences between bridges and arches. Also included are photographs, park maps, visitor information, and details on the discovery of the Owachomo, Sipapu, and Kachina Bridges.

265

Sacrificial bridges for MEMS fabrication  

NASA Astrophysics Data System (ADS)

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.

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

2011-09-01

266

Bridges of RWRE Bridges of Random Walks in a Random Environment  

E-print Network

Bridges of RWRE Bridges of Random Walks in a Random Environment Jonathon Peterson Cornell Jonathon Peterson 2/25/2010 1 / 24 #12;Bridges of RWRE Introduction Bridges of Random Walks Sn simple on {S2n = 0}? Cornell University Jonathon Peterson 2/25/2010 2 / 24 #12;Bridges of RWRE Introduction

Peterson, Jonathon

267

SoftBridge: An Architecture for Building IP-based Bridges over the Digital Divide  

E-print Network

SoftBridge: An Architecture for Building IP-based Bridges over the Digital Divide John Lewis, Bill, effective communication between the different media has be able to bridge across these options: the bridges preferences and capabilities. Our research proposes a Soft- Bridge, an abstracted communications platform

Blake, Edwin

268

Numerical investigations of the spreading-rate dependence of anomalous skewness of marine magnetic anomalies due to seafloor spreading  

NASA Astrophysics Data System (ADS)

An improved understanding of the spreading-rate dependence of anomalous skewness from magnetic anomalies due to seafloor spreading will allow for better constraints on apparent polar wander paths, plate reconstructions, and the magnetic and thermal structure of oceanic lithosphere. Anomalous skewness, which is the difference between experimentally determined skewness and skewness expected from simple magnetization models with vertical reversal boundaries, has been observed to vary as a function of spreading rate, decreasing with increasing spreading rate and becoming negligible at spreading half-rates exceeding about 55 mm/a [Roest et al. 1992; Dyment et al. 1994]. In our analysis, we determine model-based estimates of anomalous skewness as a function of spreading rate for each anomaly. We do so by creating many synthetic profiles using the model of Dyment and Arkani-Hamed (1995), which was specifically constructed to produce anomalies with anomalous skewness consistent with observed anomalies. We experimentally determine the phase shift that causes the resulting synthetic magnetic anomaly to best match a profile produced from a "standard" model for anomalies due to seafloor spreading that assumes simple vertical reversal boundaries. We present results for those anomalies between 12r and 33r from which reliable paleomagnetic poles may potentially be determined. Differences in anomalous skewness for different anomalies determined at the same spreading rate can be attributed to the sequence effect, that is, the effect on the shape of a magnetic anomaly above seafloor of a single polarity chron of the magnetization of neighboring blocks of lithosphere magnetized during other chrons. We find that the sequence effect is smaller than we expected with the largest difference being between the results for anomaly 25r and those for anomaly 33r, for which the difference is 14 degrees at a 10 mm/a half-rate. Results for other anomalies lie between these two. We also infer a small outward displacement of the magnetic anomalies, which-like anomalous skewness-decreases with increasing spreading rate and vanishes at half rates exceeding 55 mm/a. We find that results obtained trying to find the best match to the synthetic magnetic anomaly profile are generally similar to results obtained when using the balanced-shoulder criterion for when an anomaly has been successfully deskewed. The values of chron-specific (or anomaly-specific) anomalous skewness that we have determined can be used to reduce the number of adjustable parameters in the determination of paleomagnetic poles from skewness data from three to two, to simply the latitude and longitude of the paleomagnetic pole. Implications for the northward motion of the Pacific Plate will be discussed.

Boswell, S. M.; Zheng, L.; Gordon, R. G.; Dyment, J.

2011-12-01

269

Development of inspection robots for bridge cables.  

PubMed

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

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

2013-01-01

270

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

NASA Technical Reports Server (NTRS)

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.

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

1992-01-01

271

Social queuing in animal societies: a dynamic model of reproductive skew  

PubMed Central

Previously developed models of reproductive skew have overlooked one of the main reasons why subordinates might remain in a group despite restricted opportunities to breed: the possibility of social queuing, i.e. acquiring dominant status in the future. Here, we present a dynamic ESS model of skew in animal societies that incorporates both immediate and future fitness consequences of the decisions taken by group members, based on their probability of surviving from one season to the next (when post-breeding survival probabilities drop to zero, our analysis reduces to the model produced by Reeve and Ratnieks in 1993, which considered only a single breeding season). This allows us to compare the delayed benefits of philopatry and the immediate opportunities for independent breeding. We show that delayed benefits greatly reduce the need for dominants to offer reproductive concessions to retain subordinates peacefully in the group. Moreover, this effect is strong enough that differences in survival have a much greater impact on the group structure than differences in other parameters, such as relatedness. When the possibility of acceding to dominant status is taken into account, groups where the dominant completely monopolizes reproduction can be stable, even if they consist of unrelated individuals, and even if subordinates have a reasonably high probability of winning a fight for dominance. Finally, we show that stable groups are possible even if association leads to a decrease in current productivity. Subordinates may still stand to gain from group membership under these circumstances, as acquiring breeding positions by queuing may be more efficient than the attempt to establish a new territory. At the same time, the dominant may be unable to exclude unwelcome subordinates, may enjoy increased survival when they are present, or may gain indirect benefits from allowing relatives to stay and queue for dominance. We conclude that reproductive skew in animal groups, ranging from eusocial insect colonies to mating aggregations (leks), will be strongly influenced by the future prospects of group members.

Kokko, H.; Johnstone, R. A.

1999-01-01

272

Autonomous fault-tolerant attitude reference system using DTGs in symmetrically skewed configuration  

NASA Technical Reports Server (NTRS)

A novel symmetrically skewed configuration for an attitude reference system (ARS) using three dynamically tuned gyros (DTGs) is developed. Simple schemes for autonomous detection and identification of a faulty DTG in real time and subsequent reconfiguration of the attitude estimation algorithm are proposed. The performance of the present configuration is shown to be better than that of configurations proposed earlier, and it is shown to have better features. It tolerates all types of failures of DTG failures, requires very simple computations, and gives less error in attitude estimate than the other configurations.

Murugesan, S.; Goel, P. S.

1989-01-01

273

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

274

Design of a bridge bumper to protect bridge girders against collisions of overheight vehicles  

E-print Network

of the damaged bridges can be costly and time consuming. This research investigates the feasibility of developing a bridge bumper that minimizes the physical injuries and the likelihood of fatalities and protects the structural elements of bridges by absorbing...

Sharma, Hrishikesh

2009-05-15

275

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

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Movable bridge, interlocking of signal appliances with bridge devices. 236.312 Section 236.312...Interlocking Standards § 236.312 Movable bridge, interlocking of signal appliances with...

2011-10-01

276

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

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Movable bridge, interlocking of signal appliances with bridge devices. 236.312 Section 236.312...Interlocking Standards § 236.312 Movable bridge, interlocking of signal appliances with...

2013-10-01

277

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

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Movable bridge, interlocking of signal appliances with bridge devices. 236.312 Section 236.312...Interlocking Standards § 236.312 Movable bridge, interlocking of signal appliances with...

2010-10-01

278

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

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Movable bridge, interlocking of signal appliances with bridge devices. 236.312 Section 236.312...Interlocking Standards § 236.312 Movable bridge, interlocking of signal appliances with...

2012-10-01

279

East elevation of lift bridge, with U.S. Rt. 11 bridge ...  

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

East elevation of lift bridge, with U.S. Rt. 11 bridge in background. - Potomac Edison Company, Chesapeake & Ohio Canal Bridge, Spanning C & O Canal South of U.S. 11, Williamsport, Washington County, MD

280

An association between skewed X-chromosome inactivation and abnormal outcome in mosaic trisomy 16 confined predominantly to the placenta.  

PubMed

Skewed X-chromosome inactivation (XCI) is frequently found in the diploid fetal tissues of individuals with mosaic trisomy that originated from a 'trisomic zygote rescue' event. This may result from a high number of trisomic cells in the embryonic cell pool at the time of XCI, which are subsequently eliminated by selection. We hypothesize that extremely skewed XCI in these mosaic cases will be associated with a poor fetal outcome due to failure to completely eliminate the trisomy from all fetal tissues. To test this hypothesis, XCI status was evaluated in 17 cases of prenatally detected trisomy 16 mosaicism. Ten of the 15 informative cases showed extreme XCI skewing ( > or = 90% inactivation of one allele) in blood or other diploid fetal tissues compared to six of the 111 controls (p < 0.001). Among these 10 'skewed' cases, 6 showed an abnormal outcome, defined as developmental abnormalities and/or intrauterine or neonatal death. In contrast, of the 5 cases without extreme skewing, none showed abnormal outcome, although outcome information was incomplete in 1 case. An additional 6 cases analyzed, involving trisomy mosaicism for other chromosomes, showed similar results. Further studies are warranted to determine if XCI status adds useful information to the prediction of pregnancy outcome in prenatally detected mosaic trisomy. PMID:11149612

Peñaherrera, M S; Barrett, I J; Brown, C J; Langlois, S; Yong, S L; Lewis, S; Bruyère, H; Howard-Peebles, P N; Kalousek, D K; Robinson, W P

2000-12-01

281

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

DOEpatents

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.

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

1989-01-01

282

Weighted skewness and kurtosis unbiased by sample size and Gaussian uncertainties  

NASA Astrophysics Data System (ADS)

Central moments and cumulants are often employed to characterize the distribution of data. The skewness and kurtosis are particularly useful for the detection of outliers, the assessment of departures from normally distributed data, automated classification techniques and other applications. Estimators of higher order moments that are robust against outliers are more stable but might miss characteristic features of the data, as in the case of astronomical time series exhibiting brief events like stellar bursts or eclipses of binary systems, while weighting can help identify reliable measurements from uncertain or spurious outliers. Furthermore, noise is an unavoidable part of most measurements and their uncertainties need to be taken properly into account during the data analysis or biases are likely to emerge in the results, including basic descriptive statistics. This work provides unbiased estimates of the weighted skewness and kurtosis moments and cumulants, corrected for biases due to sample size and Gaussian noise, under the assumption of independent data. A comparison of biased and unbiased weighted estimators is illustrated with simulations as a function of sample size and signal-to-noise ratio, employing different data distributions and weighting schemes related to measurement uncertainties and the sampling of the signal. Detailed derivations and figures of simulation results are presented in the Appendices available online.

Rimoldini, Lorenzo

2014-07-01

283

Deconstructing risk: Separable encoding of variance and skewness in the brain  

PubMed Central

Risky choice entails a need to appraise all possible outcomes and integrate this information with individual risk preference. Risk is frequently quantified solely by statistical variance of outcomes, but here we provide evidence that individuals’ choice behaviour is sensitive to both dispersion (variance) and asymmetry (skewness) of outcomes. Using a novel behavioural paradigm in humans, we independently manipulated these ‘summary statistics’ while scanning subjects with fMRI. We show that a behavioural sensitivity to variance and skewness is mirrored in neuroanatomically dissociable representations of these quantities, with parietal cortex showing sensitivity to the former and prefrontal cortex and ventral striatum to the latter. Furthermore, integration of these objective risk metrics with subjective risk preference is expressed in a subject-specific coupling between neural activity and choice behaviour in anterior insula. Our findings show that risk is neither monolithic from a behavioural nor neural perspective and its decomposition is evident both in distinct behavioural preferences and in segregated underlying brain representations. PMID:21763444

Symmonds, Mkael; Wright, Nicholas D.; Bach, Dominik R.; Dolan, Raymond J.

2011-01-01

284

Deconstructing risk: separable encoding of variance and skewness in the brain.  

PubMed

Risky choice entails a need to appraise all possible outcomes and integrate this information with individual risk preference. Risk is frequently quantified solely by statistical variance of outcomes, but here we provide evidence that individuals' choice behaviour is sensitive to both dispersion (variance) and asymmetry (skewness) of outcomes. Using a novel behavioural paradigm in humans, we independently manipulated these 'summary statistics' while scanning subjects with fMRI. We show that a behavioural sensitivity to variance and skewness is mirrored in neuroanatomically dissociable representations of these quantities, with parietal cortex showing sensitivity to the former and prefrontal cortex and ventral striatum to the latter. Furthermore, integration of these objective risk metrics with subjective risk preference is expressed in a subject-specific coupling between neural activity and choice behaviour in anterior insula. Our findings show that risk is neither monolithic from a behavioural nor neural perspective and its decomposition is evident both in distinct behavioural preferences and in segregated underlying brain representations. PMID:21763444

Symmonds, Mkael; Wright, Nicholas D; Bach, Dominik R; Dolan, Raymond J

2011-10-15

285

Inter-population variation in multiple paternity and reproductive skew in the guppy.  

PubMed

We use microsatellite loci to detail the multiple paternity patterns in broods from 10 wild populations of the guppy (Poecilia reticulata) found in Northern Trinidad. The populations span two major drainages comprising the Caroni and the Oropouche, and include sites that are characterized by either high or low predation. Across the populations the frequency of multiple paternity is high with 95% (range: 70%-100%) of broods having multiple sires. Broods have an average of 3.5 sires (range: 1-9) and a mixed-model analysis suggests that broods from high predation sites have marginally more sires than do those from low predation sites, but this is true only in the Oropouche drainage. There is no difference in sire number between predation sites in the Caroni drainage. Brood size, but not female body length, is correlated with the number of sires and the correlation cannot be attributed solely to the stochastic process associated with sperm competition and a 'fair raffle'. Within broods there is significant skew in reproductive success among males, which may reflect variation in sperm competitiveness or female choice. There is, however, no difference in the skew among populations from different predation regimes or drainages. Finally, high predation populations were characterized by increased genetic variability at the microsatellite loci, suggesting a larger effective population size. We discuss explanations for the high degree of multiple paternity but the general lack of any major differences among broods from ecologically different populations. PMID:18494765

Neff, Bryan D; Pitcher, Trevor E; Ramnarine, Indar W

2008-06-01

286

Bridging the Vector Calculus Gap  

NSDL National Science Digital Library

This paper was written collaboratively by a physicist and a mathematician to raise awareness about the "vector calculus gap" and offer realistic solutions to bridge the gap. The authors define the vector calculus gap as a disparity between the way mathematicians and physical scientists think about vectors, which they argue results in performance difficulties for students of physics and engineering. In this paper, they advocate emphasizing geometric reasoning over algebraic computation when introducing vectors. In addition, their proposed instructional method uses differentials to bridge the vector calculus gap. Included are sample group activities and tips for incorporating these ideas in the classroom. SEE RELATED ITEMS BELOW for a link to the authors' full web site on Bridging the Vector Calculus Gap.

Dray, Tevian; Manogue, Corinne A.

2008-12-23

287

Bridge Construction and Engineering Learning Center  

NSDL National Science Digital Library

This website is a great resource for information on bridges. The site provides links to websites like PBS's Nova, where you can learn about different types of bridges and then test your knowledge by matching the right bridge to the right location (over a freeway, river, canyon or ocean waterway), or where you can read more about the forces, loads and materials that affect bridges. Another link takes you to Better Bridges, where you can find out how many bridges are in your state. Definitely a great resource for those armchair engineers but also for teachers and students of physics looking for some great information on this fascinating type of construction.

288

Level II scour analysis for Bridge 38 (BETHTH00070038) on Town Highway 007, crossing Gilead Brook, Bethel, Vermont  

USGS Publications Warehouse

The town highway 5 crossing of the Black River is a 70-ft-long, two-lane bridge consisting of one 65-foot clear span (Vermont Agency of Transportation, written commun., August 2, 1994). The bridge is supported by vertical, concrete abutments with wingwalls. There is also a retaining wall along the upstream side of the road embankments. The channel is skewed approximately 20 degrees to the opening while the opening-skew-to-roadway is 15 degrees. A scour hole 3.0 ft deeper than the mean thalweg depth was observed along the right abutment. The scour hole was 27 feet long, 15 feet wide, and was 2.5 feet below the abutment footing at the time of the Level I assessment. This right abutment had numerous cracks and had settled. 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.

Ivanoff, Michael A.; Song, Donald L.

1996-01-01

289

Excitation Methods for Bridge Structures  

SciTech Connect

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.

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

1999-02-08

290

Balanced bridge feedback control system  

NASA Technical Reports Server (NTRS)

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.

Lurie, Boris J. (inventor)

1990-01-01

291

Stochastic bridges of linear systems  

E-print Network

We study a generalization of the Brownian bridge as a stochastic process that models the position and velocity of inertial particles between the two end-points of a time interval. The particles experience random acceleration and are assumed to have known states at the boundary. Thus, the movement of the particles can be modeled as an Ornstein-Uhlenbeck process conditioned on position and velocity measurements at the two end-points. It is shown that optimal stochastic control provides a stochastic differential equation (SDE) that generates such a bridge as a degenerate diffusion process. Generalizations to higher order linear diffusions are considered.

Yongxin Chen; Tryphon Georgiou

2014-07-12

292

Evolutionary Semigroups and Dichotomy of Linear Skew-Product Flows on Locally Compact Spaces with Banach Fibers  

NASA Astrophysics Data System (ADS)

We study evolutionary semigroups generated by a strongly continuous semi-cocycle over a locally compact metric space acting on Banach fibers. This setting simultaneously covers evolutionary semigroups arising from non-autonomous abstract Cauchy problems and C0-semigroups, and linear skew-product flows. The spectral mapping theorem for these semigroups is proved. The hyperbolicity of the semigroup is related to the exponential dichotomy of the corresponding linear skew-product flow. To this end a Banach algebra of weighted composition operators is studied. The results are applied in the study of: "roughness" of the dichotomy, dichotomy and solutions of nonhomogeneous equations, Green's function for a linear skew-product flow, "pointwise" dichotomy versus "global" dichotomy, and evolutionary semigroups along trajectories of the flow.

Latushkin, Y.; Montgomery-Smith, S.; Randolph, T.

293

NASA Now: Operation IceBridge  

NASA Video Gallery

During this NASA Now program, you'??ll meet Michael Studinger, Project Scientist for Operation IceBridge. He'??ll describe the purpose of the IceBridge campaign and how the campaign objectives will...

294

Performance Analysis of LAN Bridges and Routers.  

National Technical Information Service (NTIS)

Bridges and routers are used to interconnect Local Area Networks (LANs). The performance of these devices is important since they can become bottlenecks in large multi-segment networks. Performance metrics and test methodology for bridges and routers were...

A. R. Hajare

1991-01-01

295

Approach to Setting Bridge Crossing Rating Criteria.  

National Technical Information Service (NTIS)

Document describes a methodology for rating bridges for non-normal crossing conditions. This methodology is based on probability of failure calculations, for normal crossings, for the recommended caution crossing rating the bridge will have the same proba...

P. D. Hilton, P. R. Nayak

1983-01-01

296

Wind effect on long span bridge  

E-print Network

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 ...

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

2012-01-01

297

Seismic Design of Monolithic Bridge Abutments,  

National Technical Information Service (NTIS)

The objective of the research was to investigate the soil-structure interaction characteristics between monolithic bridge abutments and the surrounding soil. The investigation consisted of: (1) vibration tests on the Horsethief Bridge, a single span struc...

B. Hushmand, C. B. Crouse, G. Liang, G. Martin, J. Wood

1986-01-01

298

Determination of Bridge Response Using Acceleration Data.  

National Technical Information Service (NTIS)

Knowledge of the actual displacement response of a bridge subjected to random traffic loading is useful in evaluating bridge performance and serviceability. However, mounting displacement transducers is difficult, and the feasibility of and cost associate...

B. C. Faulkner, F. W. Barton, T. T. Baber, W. T. McKeel

1996-01-01

299

A decomposition theorem for the space of C^1-smooth skew products with complicated dynamics of the quotient map  

NASA Astrophysics Data System (ADS)

We use the notions of the \\Omega-function and functions suitable to it, to give a detailed proof of a decomposition theorem for the space of C^{1}-smooth skew products of interval maps whose quotient maps have complicated dynamics and satisfy the additional condition of \\Omega-stability with respect to the C^1-norm. In our theorem, the space of C^1-smooth skew products is decomposed into a union of four nonempty, pairwise disjoint subspaces. We give examples of maps contained in each of the four subspaces. Bibliography: 46 titles.

Efremova, L. S.

2013-11-01

300

Bridges on the River Quad  

NSDL National Science Digital Library

In this activity, students graph a quadratic function that models the shape of a bridge trestle and then solve the related quadratic equation by completing the square. Students use the calculatorsâ capabilities to find the x-intercepts and the maximum value on the graph. Teacher notes, detailed instructions on using graphing calculators, and questions to check comprehension aid in teaching the lesson.

2011-03-27

301

A Bridge to the Future  

ERIC Educational Resources Information Center

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…

Anderson, Richard

2008-01-01

302

The Bridge to Manufacturing Project  

ERIC Educational Resources Information Center

A grant project was designed to facilitate the transition of students from a community college adult education program into a community college credit-degree program in manufacturing. Key features of the program included a focus on identifying policy implications; bridging the separation between the adult education segment of the community college…

Puchner, Laurel; Taylor, Ann R.; Harris, Valorie K.; Marshall, Rick W.; Powell, Margaret

2010-01-01

303

WSC Bridge Program Planning Guide  

ERIC Educational Resources Information Center

Increasingly jobs that pay more than subsistence wages and offer opportunities for career advancement require at least some training beyond high school, even at the entry level. Bridge training programs are designed to prepare individuals without the requisite basic skills for postsecondary training leading to career-path employment and further…

Jenkins, Davis

2004-01-01

304

to China: A Bridge Between  

E-print Network

From Yale to China: A Bridge Between Cultures Students often invoke the metaphor of a journey in China," she said. "Yale oered a vast array of resources to help me improve my language compe- tency program and myriad exchanges with China. The summer before her sophomore year at Yale, Jenna received

305

Bridge Funding Program 2007 Awardees  

E-print Network

Reactivity Model for Assessing Pharmacologic Intervention in Treatment of Cannabis Use Disorders Ananda-Assisted Integrated Approach for Enhancing Bridge Health Monitoring Guri Tzivion, Pathology Regulation of c-Raf-1 on Preimplantation Mouse Development Melissa Runge-Morris, Institute of Environmental Health Sciences

Berdichevsky, Victor

306

"Sand Boil" on Bay Bridge  

USGS Multimedia Gallery

"Sand boil" or sand volcano measuring 2 m (6.6 ft) in length erupted in median of Interstate Highway 80 west of the Bay Bridge toll plaza when ground shaking transformed loose water-saturated deposit of subsurface sand into a sand-water slurry (liquefaction). Vented sand contains-marine shell f...

2009-01-26

307

Skart: A skewness- and autoregression-adjusted batch-means procedure for simulation analysis  

NASA Astrophysics Data System (ADS)

We discuss Skart, an automated batch-means procedure for constructing a skewness- and autoregression-adjusted confidence interval (CI) for the steady-state mean of a simulation output process in either discrete time (i.e., observation-based statistics) or continuous time (i.e., time-persistent statistics). Skart is a sequential procedure designed to deliver a CI that satisfies user-specified requirements concerning not only the CI's coverage probability but also the absolute or relative precision provided by its half-length. Skart exploits separate adjustments to the half-length of the classical batchmeans CI so as to account for the effects on the distribution of the underlying Student's t-statistic that arise from skewness (nonnormality) and autocorrelation of the batch means. The skewness adjustment is based on a modified Cornish-Fisher expansion for the classical batch-means Student's t -ratio, and the autocorrelation adjustment is based on an autoregressive approximation to the batch-means process for sufficiently large batch sizes. Skart also delivers a point estimator for the steady-state mean that is approximately free of initialization bias. The duration of the associated warm-up period (i.e., the statistics clearing time) is based on iteratively applying von Neumann's randomness test to spaced batch means with progressively increasing batch sizes and interbatch spacer sizes. In an experimental performance evaluation involving a wide range of test processes, Skart compared favorably with other simulation analysis methods---namely, its predecessors ASAP3, WASSP, and SBatch as well as ABATCH, LBATCH, the Heidelberger-Welch procedure, and the Law-Carson procedure. Specifically, Skart exhibited competitive sampling efficiency and substantially closer conformance to the given CI coverage probabilities than the other procedures. Also presented is a nonsequential version of Skart, called N-Skart, in which the user supplies a single simulation-generated series of arbitrary length and specifies a coverage probability for a CI based on that series. In the same set of test processes previously mentioned and for a range of data-set sizes, N-Skart also achieved close conformance to the specified CI coverage probabilities.

Tafazzoli Yazdi, Ali

308

NONLINEAR AERODYNAMIC ANALYSIS OF BRIDGES UNDER TURBULENT WINDS: THE NEW FRONTIER IN BRIDGE  

E-print Network

with the conventional linear approach is made through response analysis of a long-span suspension bridge. KEYWORDSNONLINEAR AERODYNAMIC ANALYSIS OF BRIDGES UNDER TURBULENT WINDS: THE NEW FRONTIER IN BRIDGE. In this study, a time domain analysis framework for predicting the flutter and buffeting responses of bridges

Kareem, Ahsan

309

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

ERIC Educational Resources Information Center

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…

Taylor, J. L.; Harmon, T.

2010-01-01

310

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

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Watch required by the Bridge-to-Bridge Act. 80.309 Section 80.309 Telecommunication...Safety Watches § 80.309 Watch required by the Bridge-to-Bridge Act. In addition to the watch...

2011-10-01

311

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

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Operator requirements of the Bridge-to-Bridge Act. 80.163 Section 80.163 Telecommunication...Requirements § 80.163 Operator requirements of the Bridge-to-Bridge Act. Each ship subject to the...

2013-10-01

312

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

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Operator requirements of the Bridge-to-Bridge Act. 80.163 Section 80.163 Telecommunication...Requirements § 80.163 Operator requirements of the Bridge-to-Bridge Act. Each ship subject to the...

2012-10-01

313

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

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Operator requirements of the Bridge-to-Bridge Act. 80.163 Section 80.163 Telecommunication...Requirements § 80.163 Operator requirements of the Bridge-to-Bridge Act. Each ship subject to the...

2010-10-01

314

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

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Watch required by the Bridge-to-Bridge Act. 80.309 Section 80.309 Telecommunication...Safety Watches § 80.309 Watch required by the Bridge-to-Bridge Act. In addition to the watch...

2013-10-01

315

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

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Operator requirements of the Bridge-to-Bridge Act. 80.163 Section 80.163 Telecommunication...Requirements § 80.163 Operator requirements of the Bridge-to-Bridge Act. Each ship subject to the...

2011-10-01

316

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

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Watch required by the Bridge-to-Bridge Act. 80.309 Section 80.309 Telecommunication...Safety Watches § 80.309 Watch required by the Bridge-to-Bridge Act. In addition to the watch...

2010-10-01

317

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

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Watch required by the Bridge-to-Bridge Act. 80.309 Section 80.309 Telecommunication...Safety Watches § 80.309 Watch required by the Bridge-to-Bridge Act. In addition to the watch...

2012-10-01

318

49 CFR 237.33 - Content of bridge management programs.  

Code of Federal Regulations, 2010 CFR

...33 Content of bridge management programs. Each bridge management program adopted in compliance...bridge, its location, configuration, type of construction...necessary to provide for the management of bridge safety;...

2010-10-01

319

49 CFR 237.103 - Bridge inspection procedures.  

Code of Federal Regulations, 2013 CFR

... 4 2013-10-01 2013-10-01 false Bridge inspection procedures. 237.103 Section 237...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.103 Bridge inspection...

2013-10-01

320

49 CFR 237.53 - Railroad bridge inspectors.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Railroad bridge inspectors. 237.53 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and...Responsible Persons § 237.53 Railroad bridge inspectors. A railroad bridge...

2012-10-01

321

49 CFR 237.53 - Railroad bridge inspectors.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Railroad bridge inspectors. 237.53 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and...Responsible Persons § 237.53 Railroad bridge inspectors. A railroad bridge...

2010-10-01

322

49 CFR 237.103 - Bridge inspection procedures.  

Code of Federal Regulations, 2010 CFR

... 4 2010-10-01 2010-10-01 false Bridge inspection procedures. 237.103 Section 237...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.103 Bridge inspection...

2010-10-01

323

23 CFR 650.807 - Bridges requiring a USCG permit.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Bridges requiring a USCG permit. 650.807... ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.807 Bridges requiring a...

2012-04-01

324

49 CFR 237.111 - Review of bridge inspection reports.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Review of bridge inspection reports. 237.111 Section 237...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.111 Review of bridge...

2010-10-01

325

23 CFR 650.807 - Bridges requiring a USCG permit.  

...2014-04-01 2014-04-01 false Bridges requiring a USCG permit. 650.807... ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.807 Bridges requiring a...

2014-04-01

326

49 CFR 237.111 - Review of bridge inspection reports.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Review of bridge inspection reports. 237.111 Section 237...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.111 Review of bridge...

2011-10-01

327

49 CFR 237.107 - Conduct of bridge inspections.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Conduct of bridge inspections. 237.107 Section 237.107 ...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.107 Conduct of bridge...

2013-10-01

328

49 CFR 237.107 - Conduct of bridge inspections.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Conduct of bridge inspections. 237.107 Section 237.107 ...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.107 Conduct of bridge...

2012-10-01

329

23 CFR 650.807 - Bridges requiring a USCG permit.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Bridges requiring a USCG permit. 650.807... ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.807 Bridges requiring a...

2013-04-01

330

49 CFR 237.103 - Bridge inspection procedures.  

Code of Federal Regulations, 2011 CFR

... 4 2011-10-01 2011-10-01 false Bridge inspection procedures. 237.103 Section 237...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.103 Bridge inspection...

2011-10-01

331

33 CFR 118.90 - Bridges crossing channel obliquely.  

Code of Federal Regulations, 2013 CFR

...Waters 1 2013-07-01 2013-07-01 false Bridges crossing channel obliquely. 118.90 Section 118...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.90 Bridges...

2013-07-01

332

33 CFR 118.90 - Bridges crossing channel obliquely.  

Code of Federal Regulations, 2012 CFR

...Waters 1 2012-07-01 2012-07-01 false Bridges crossing channel obliquely. 118.90 Section 118...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.90 Bridges...

2012-07-01

333

49 CFR 237.111 - Review of bridge inspection reports.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Review of bridge inspection reports. 237.111 Section 237...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.111 Review of bridge...

2013-10-01

334

49 CFR 237.107 - Conduct of bridge inspections.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Conduct of bridge inspections. 237.107 Section 237.107 ...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.107 Conduct of bridge...

2011-10-01

335

49 CFR 237.107 - Conduct of bridge inspections.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Conduct of bridge inspections. 237.107 Section 237.107 ...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.107 Conduct of bridge...

2010-10-01

336

49 CFR 237.53 - Railroad bridge inspectors.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Railroad bridge inspectors. 237.53 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and...Responsible Persons § 237.53 Railroad bridge inspectors. A railroad bridge...

2013-10-01

337

23 CFR 650.807 - Bridges requiring a USCG permit.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Bridges requiring a USCG permit. 650.807... ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.807 Bridges requiring a...

2011-04-01

338

33 CFR 118.90 - Bridges crossing channel obliquely.  

Code of Federal Regulations, 2011 CFR

...Waters 1 2011-07-01 2011-07-01 false Bridges crossing channel obliquely. 118.90 Section 118...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.90 Bridges...

2011-07-01

339

33 CFR 118.90 - Bridges crossing channel obliquely.  

Code of Federal Regulations, 2010 CFR

...Waters 1 2010-07-01 2010-07-01 false Bridges crossing channel obliquely. 118.90 Section 118...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.90 Bridges...

2010-07-01

340

49 CFR 237.109 - Bridge inspection records.  

Code of Federal Regulations, 2013 CFR

... 4 2013-10-01 2013-10-01 false Bridge inspection records. 237.109 Section 237...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.109 Bridge inspection...

2013-10-01

341

49 CFR 237.103 - Bridge inspection procedures.  

Code of Federal Regulations, 2012 CFR

... 4 2012-10-01 2012-10-01 false Bridge inspection procedures. 237.103 Section 237...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.103 Bridge inspection...

2012-10-01

342

49 CFR 237.111 - Review of bridge inspection reports.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Review of bridge inspection reports. 237.111 Section 237...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.111 Review of bridge...

2012-10-01

343

49 CFR 237.109 - Bridge inspection records.  

Code of Federal Regulations, 2012 CFR

... 4 2012-10-01 2012-10-01 false Bridge inspection records. 237.109 Section 237...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.109 Bridge inspection...

2012-10-01

344

49 CFR 237.53 - Railroad bridge inspectors.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Railroad bridge inspectors. 237.53 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and...Responsible Persons § 237.53 Railroad bridge inspectors. A railroad bridge...

2011-10-01

345

Conservation of Salt Bridges in Protein Families  

Microsoft Academic Search

A detailed computational analysis is presented that focuses on the relationship between structural attributes and the degree and mode of salt bridge conservation. A data set of conserved and non-conserved salt bridges was constructed from eight protein families, based on the structural alignment of family members. Salt bridges were defined at the secondary structure level rather than at the residue

Ora Schueler; Hanah Margalit

1995-01-01

346

Building Bridges One Line at a Time  

ERIC Educational Resources Information Center

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…

Grigsby, Cathy Murray

2012-01-01

347

Imaging radar for bridge deck inspection  

Microsoft Academic Search

Lawrence Livermore National Laboratory is developing a prototype imaging radar for inspecting steel reinforced concrete bridge decks. The system is designed to acquire synthetic aperture radar data and provide high-resolution images of internal structure, flaws, and defects enabling bridge inspectors to nondestructively evaluate and characterized bridge deck condition. Concrete delamination resulting from corrosion of steel reinforcing bars (rebars) is an

John P. Warhus; Jeffrey E. Mast; Scott D. Nelson

1995-01-01

348

Removal of failed crown and bridge  

PubMed Central

Crown and bridge have life span of many years but they fail for a number of reasons. Over the years, many devices have been designed to remove crowns and bridges from abutment teeth. While the removal of temporary crowns and bridges is usually very straightforward, the removal of a definitive cast crown with unknown cement is more challenging. Removal is often by destructive means. There are a number of circumstances, however, in which conservative disassembly would aid the practitioner in completing restorative/endodontic procedures. There are different mechanisms available to remove a failed crown or bridge. But there is no information published about the classification of available systems for crown and bridge removal. So it is logical to classify these systems into different groups which can help a clinician in choosing a particular type of system depending upon the clinical situation. The aim of this article is to provide a classification for various crown and bridge removal systems; describe how a number of systems work; and when and why they might be used. A PubMed search of English literature was conducted up to January 2010 using the terms: Crown and bridge removal, Crown and bridge disassembly, Crown and bridge failure. Additionally, the bibliographies of 3 previous reviews, their cross references as well as articles published in various journals like International Endodontic Journal, Journal of Endodontics and were manually searched. Key words:Crown and bridge removal, Crown and bridge disassembly, Crown and bridge failure. PMID:24558549

Rahul, G R.; Poduval, Soorya T.; Shetty, Karunakar

2012-01-01

349

Dynamic response of highway girder bridges  

Microsoft Academic Search

The objective of the paper is to investigate the variation of dynamic loading of girder bridges with different girder number and span length due to several vehicles moving across rough bridge decks. Nine girder bridges with girder number ranging from four to eight and span length changing from 40 to 120 ft are designed based on the AASHTO standard highway

Ton-Lo Wang; Dongzhou Huang; Mohsen Shahawy; Kaizan Huang

1996-01-01

350

Simulation of multivariate diffusion bridges Mogens Bladt  

E-print Network

Simulation of multivariate diffusion bridges Mogens Bladt Instituto de Investigacion en Matem Abstract We propose simple methods for multivariate diffusion bridge simulation, which plays a fundamental simulation method for one-dimensional bridges to the multi-variate setting. First a method of simulating

Sørensen, Michael

351

MARKOVIAN BRIDGES: WEAK CONTINUITY AND PATHWISE CONSTRUCTIONS  

E-print Network

MARKOVIAN BRIDGES: WEAK CONTINUITY AND PATHWISE CONSTRUCTIONS LO¨IC CHAUMONT AND GER´ONIMO URIBE BRAVO Abstract. A Markovian bridge is a probability measure taken from a disintegration of the law of an initial part of the path of a Markov process given its terminal value. As such, Markovian bridges admit

Paris-Sud XI, Université de

352

PALESTRA -PPGEC Efficient Management of Bridges  

E-print Network

PALESTRA - PPGEC Efficient Management of Bridges Ales Znidaric Slovenian National Building and Civil Engineering Institute Dia: 26/03/2012 Hora: 14:00 Local: Auditório PPGEC #12;Resumo: Bridges planning of rehabilitation measures is often difficult as bridges deteriorate while loading over time

Floeter, Sergio Ricardo

353

Remediation: Higher Education's Bridge to Nowhere  

ERIC Educational Resources Information Center

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…

Complete College America, 2012

2012-01-01

354

CONVEX, ROTATIONALLY SYMMETRIC LIQUID BRIDGES BETWEEN SPHERES  

E-print Network

CONVEX, ROTATIONALLY SYMMETRIC LIQUID BRIDGES BETWEEN SPHERES Thomas I. Vogel Department of Mathematics Texas A&M University College Station, TX 77843 tvogel@math.tamu.edu A liquid bridge between two different contact an- gles: one for each ball). If we consider rotationally symmetric bridges, then the free

Vogel, Thomas

355

A Participatory Public Art Project: Community Bridge  

ERIC Educational Resources Information Center

This article introduces Community Bridge, a participatory public art project that brought together artists and residents to address aesthetic needs of an urban environment. The Community Bridge is an exemplary work of art by American artist William Cochran. In addition to creating a natural gathering place for residents of all ages, the bridge is…

Stephens, Pam

2005-01-01

356

MELISSA E. BRIDGES melbrid@gmail.com  

E-print Network

MELISSA E. BRIDGES melbrid@gmail.com Education: Ph.D. Ecology and Environmental Sciences Expected, South Carolina Professional Development (Selected Publications and Presentations): Bridges, M., B]. Bridges, M., B.D. Maxwell, J. Rotella, and L.J. Rew. 2009. Evaluating the relationship between invasive

Maxwell, Bruce D.

357

ADVANCED COMPOSITE MATERIALS FOR BRIDGES Sami RIZKALLA  

E-print Network

1. SUMMARY ADVANCED COMPOSITE MATERIALS FOR BRIDGES Sami RIZKALLA ISIS Canada Network of Centres bridges are being built with materials that have significantly higher strength in comparison to steel associated with concrete bridges due to the corrosion of steel reinforcements. This paper presents

358

Obliterable of graphics and correction of skew using Hough transform for mobile captured documents  

NASA Astrophysics Data System (ADS)

CBDA is an emerging field in Computer Vision and Pattern Recognition. In recent technology camera are incorporated to several electronic equipments and are very interesting and thus playing a vital role by replacing scanner with hand held imaging devices like Digital Cameras, Mobile phones and gaming devices attached with these camera. The goal of the work is to remove graphics from the document which plays a vital role in recognition of characters from the mobile captured documents. In this paper we have proposed a novel method for separating or removal of graphics like logos, animations other than the text from the document and method to reduce noise and finally textual content skew is estimated and corrected using Hough Transform. The experimental results show the efficacy compared to the result of well known existing methods.

Chethan, H. K.; Kumar, G. Hemantha

2011-10-01

359

Skew orthogonal polynomials for the real and quaternion real Ginibre ensembles and generalizations  

NASA Astrophysics Data System (ADS)

There are some distinguished ensembles of non-Hermitian random matrices for which the joint probability density function can be written down explicitly, are unchanged by rotations, and furthermore which have the property that the eigenvalues form a Pfaffian point process. For these ensembles, in which the elements of the matrices are either real, or real quaternion, the kernel of the Pfaffian is completely determined by certain skew orthogonal polynomials, which permit an expression in terms of averages over the characteristic polynomial, and the characteristic polynomial multiplied by the trace. We use Schur polynomial theory, knowledge of the value of a Schur polynomial averaged against real, and real quaternion Gaussian matrices, and the Selberg integral to evaluate these averages.

Forrester, Peter J.

2013-06-01

360

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

E-print Network

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...

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

2011-01-01

361

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

SciTech Connect

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.

Morita, Daisuke; Miyamoto, Ayumi; Hattori, Yuki; Komori, Takaya [Laboratory of Cell Regulation, Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan)] [Laboratory of Cell Regulation, Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Nakamura, Takashi [Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812 (Japan)] [Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812 (Japan); Igarashi, Tatsuhiko, E-mail: tigarash@virus.kyoto-u.ac.jp [Laboratory of Primate Model, Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan)] [Laboratory of Primate Model, Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Harashima, Hideyoshi, E-mail: harasima@pharm.hokudai.ac.jp [Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812 (Japan)] [Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812 (Japan); Sugita, Masahiko, E-mail: msugita@virus.kyoto-u.ac.jp [Laboratory of Cell Regulation, Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan)] [Laboratory of Cell Regulation, Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan)

2013-11-08

362

Numeric and symbolic evaluation of the pfaffian of general skew-symmetric matrices  

NASA Astrophysics Data System (ADS)

Evaluation of pfaffians arises in a number of physics applications, and for some of them a direct method is preferable to using the determinantal formula. We discuss two methods for the numerical evaluation of pfaffians. The first is tridiagonalization based on Householder transformations. The main advantage of this method is its numerical stability that makes unnecessary the implementation of a pivoting strategy. The second method considered is based on Aitken's block diagonalization formula. It yields to a kind of LU (similar to Cholesky's factorization) decomposition (under congruence) of arbitrary skew-symmetric matrices that is well suited both for the numeric and symbolic evaluations of the pfaffian. Fortran subroutines (FORTRAN 77 and 90) implementing both methods are given. We also provide simple implementations in Python and Mathematica for purpose of testing, or for exploratory studies of methods that make use of pfaffians. Program summaryProgram title:PFAFFIAN Catalogue identifier: AEJD_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEJD_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 2281 No. of bytes in distributed program, including test data, etc.: 13 226 Distribution format: tar.gz Programming language: Fortran 77 and 90 Computer: Any supporting a FORTRAN compiler Operating system: Any supporting a FORTRAN compiler RAM: a few MB Classification: 4.8 Nature of problem: Evaluation of the pfaffian of a skew symmetric matrix. Evaluation of pfaffians arises in a number of physics applications involving fermionic mean field wave functions and their overlaps. Solution method: Householder tridiagonalization. Aitken's block diagonalization formula. Additional comments: Python and Mathematica implementations are provided in the main body of the paper. Running time: Depends on the size of the matrices. For matrices with 100 rows and columns a few milliseconds are required.

González-Ballestero, C.; Robledo, L. M.; Bertsch, G. F.

2011-10-01

363

Low paternity skew and the influence of maternal kin in an egalitarian, patrilocal primate  

PubMed Central

Levels of reproductive skew vary in wild primates living in multimale groups depending on the degree to which high-ranking males monopolize access to females. Still, the factors affecting paternity in egalitarian societies remain unexplored. We combine unique behavioral, life history, and genetic data to evaluate the distribution of paternity in the northern muriqui (Brachyteles hypoxanthus), a species known for its affiliative, nonhierarchical relationships. We genotyped 67 individuals (22 infants born over a 3-y period, their 21 mothers, and all 24 possible sires) at 17 microsatellite marker loci and assigned paternity to all infants. None of the 13 fathers were close maternal relatives of females with which they sired infants, and the most successful male sired a much lower percentage of infants (18%) than reported for the most successful males in other species. Our findings of inbreeding avoidance and low male reproductive skew are consistent with the muriqui's observed social and sexual behavior, but the long delay (?2.08 y) between the onset of male sexual behavior and the age at which males first sire young is unexpected. The allocation of paternity implicates individual male life histories and access to maternal kin as key factors influencing variation in paternal—and grandmaternal—fitness. The apparent importance of lifelong maternal investment in coresident sons resonates with other recent examinations of maternal influences on offspring reproduction. This importance also extends the implications of the “grandmother hypothesis” in human evolution to include the possible influence of mothers and other maternal kin on male reproductive success in patrilocal societies. PMID:22065786

Strier, Karen B.; Chaves, Paulo B.; Mendes, Sergio L.; Fagundes, Valeria; Di Fiore, Anthony

2011-01-01

364

2014 APPLICATION FORM BRIDGING TRIBAL COLLEGE STUDENTS TO MONTANA STATE UNIVERSITY (BRIDGES)  

E-print Network

and a suspension bridge? Which type permits a longer span? Give three different types of bridges and the span is the average speed of the bicyclists in mi/hr and ft/s. Bridges What's the difference between a steel truss that is typical for each type of bridge. What is the most common type of bridge? Why is it so common? Is this type

365

Performance analysis of LAN bridges and routers  

NASA Technical Reports Server (NTRS)

Bridges and routers are used to interconnect Local Area Networks (LANs). The performance of these devices is important since they can become bottlenecks in large multi-segment networks. Performance metrics and test methodology for bridges and routers were not standardized. Performance data reported by vendors is not applicable to the actual scenarios encountered in an operational network. However, vendor-provided data can be used to calibrate models of bridges and routers that, along with other models, yield performance data for a network. Several tools are available for modeling bridges and routers - Network II.5 was used. The results of the analysis of some bridges and routers are presented.

Hajare, Ankur R.

1991-01-01

366

Theory of water and charged liquid bridges  

E-print Network

The phenomena of liquid bridge formation due to an applied electric field is investigated. A new solution for the charged catenary is presented which allows to determine the static and dynamical stability conditions where charged liquid bridges are possible. The creeping height, the bridge radius and length as well as the shape of the bridge is calculated showing an asymmetric profile in agreement with observations. The flow profile is calculated from the Navier Stokes equation leading to a mean velocity which combines charge transport with neutral mass flow and which describes recent experiments on water bridges.

Klaus Morawetz

2011-07-03

367

Design of skewed mounted permanent magnet synchronous generators based on 2D and 3D finite element techniques  

Microsoft Academic Search

This paper investigates the effects of rotor skew on the performance of permanent magnet synchronous generators. The main effects are concerning reduction of the electromotive force induced, stator current harmonics and torque ripple. The analysis performed is based on various 2D and 3D finite element techniques. Simulation results are compared to measurements.

Themistoklis Kefalas; George Kalokiris; Antonios Kladas; John Tegopoulos

2005-01-01

368

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

E-print Network

golden lion tamarins (Leontopithecus rosalia) MaLinda D. Henry, Sarah J. Hankerson, Jennifer M. Siani reproductive skew in wild golden lion tamarins (Leontopithecus rosalia), Hormones and Behavior (2013), doi: 10 in wild golden lion tamarins (Leontopithecus rosalia) MaLinda D. Henrya* , Sarah J. Hankersona1 , Jennifer

French, Jeffrey A.

369

Female dominance status and fecal corticoids in a cooperative breeder with low reproductive skew: ring-tailed lemurs ( Lemur catta)  

Microsoft Academic Search

Many studies have shown that low dominance status within a social group is associated with elevated glucocorticoid hormone production, a common index of physiological stress. However, the reverse may be true among cooperatively breeding female mammals with high reproductive skew; that is, high dominance status is associated with elevated glucocorticoid levels. Elevated glucocorticoid levels in these dominant females may be

S. A. Cavigelli; T. Dubovick; W. Levash; A. Jolly; A. Pittsd

2003-01-01

370

Giant Spin Hall Effect Induced by Skew Scattering from Bismuth Impurities inside Thin Film CuBi Alloys  

E-print Network

, based on a three-dimensional (3D) finite element treatment of the spin transport equations [16], the SHGiant Spin Hall Effect Induced by Skew Scattering from Bismuth Impurities inside Thin Film Cu 2012) We demonstrate that a giant spin Hall effect (SHE) can be induced by introducing a small amount

Otani, Yoshichika

371

On the dependence of the leak-rate of seals on the skewness of the surface height probability distribution  

E-print Network

Seals are extremely useful devices to prevent fluid leakage. We present experimental result which show that the leak-rate of seals depend sensitively on the skewness in the height probability distribution. The experimental data are analyzed using the critical-junction theory. We show that using the top-power spectrum result in good agreement between theory and experiment.

B. Lorenz; B. N. J. Persson

2010-04-07

372

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

NASA Astrophysics Data System (ADS)

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.

Pipie?, M.

2008-09-01

373

Analysis and Investigation of Skew Effect on Behavior and Performance of a Small Scale Three-Phase Self-Excited Induction Generator  

NASA Astrophysics Data System (ADS)

This paper presents analysis and investigation of the skew effect on behavior and performance of a three-phase, 220/380V, 8.7/5.0A, ?/Y connected, 4 poles, 2.2kW self-excited induction generator (SEIG) with different angles rotor skewing. A 2D finite element analysis (2D-FEA) is used to consider core loss, flux density and circuit parameters. Analysis of excitation capacitor values for the SEIG based on a steady-state equivalent circuit model including rotor skew effect is given. Skewed rotor slots with angle of 0° (non-skew), 5° and 10° for the SEIGs are employed. Testing and performance comparisons under steady-state operation with a pure resistive load have been conducted. Obtained results can be guidelines and recommendations for development of effective wind induction generators.

Sawetsakulanond, Budhapon; Kinnares, Vijit

374

Robot-Assisted Bridge Inspection  

Microsoft Academic Search

The Center for Robot-Assisted Search and Rescue (CRASAR®) deployed a customized AEOS man-portable unmanned surface vehicle\\u000a and two commercially available underwater vehicles (the autonomous YSI EcoMapper and the tethered VideoRay) for inspection\\u000a of the Rollover Pass bridge in the Bolivar peninsula of Texas in the aftermath of Hurricane Ike. A preliminary domain analysis\\u000a with the vehicles identified key tasks in

Robin R. Murphy; Eric Steimle; Michael Hall; Michael Lindemuth; David Trejo; Stefan Hurlebaus; Zenon Medina-Cetina; Daryl Slocum

375

Bridging Nonliving and Living Matter  

Microsoft Academic Search

Assembling non-biological materials (geomaterials) into a proto-organism constitutes a bridge between nonliving and living matter. In this article we present a simple step-by-step route to assemble a proto-organism. Many pictures have been proposed to describe this transition within the origins-of-life and artificial life communities, and more recently alternative pictures have been emerging from advances in nanoscience and biotechnology. The proposed

Steen Rasmussen; Liaohai Chen; Martin Nilsson; Shigeaki Abe

2003-01-01

376

Halliburton Composite Bridge Plug Assembly  

SciTech Connect

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.

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

2005-01-15

377

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

USGS Publications Warehouse

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.

Brabets, T. P.

1994-01-01

378

Salt Bridges: Geometrically Specific, Designable Interactions  

PubMed Central

Salt bridges occur frequently in proteins, providing conformational specificity and contributing to molecular recognition and catalysis. We present a comprehensive analysis of these interactions in protein structures by surveying a large database of protein structures. Salt bridges between Asp or Glu and His, Arg, or Lys display extremely well-defined geometric preferences. Several previously observed preferences are confirmed and others that were previously unrecognized are discovered. Salt bridges are explored for their preferences for different separations in sequence and in space, geometric preferences within proteins and at protein-protein interfaces, cooperativity in networked salt bridges, inclusion within metal-binding sites, preference for acidic electrons, apparent conformational side chain entropy reduction upon formation, and degree of burial. Salt bridges occur far more frequently between residues at close than distant sequence separations, but at close distances there remain strong preferences for salt bridges at specific separations. Specific types of complex salt bridges, involving three or more members, are also discovered. As we observe a strong relationship between the propensity to form a salt bridge and the placement of salt-bridging residues in protein sequences, we discuss the role that salt bridges might play in kinetically influencing protein folding and thermodynamically stabilizing the native conformation. We also develop a quantitative method to select appropriate crystal structure resolution and B-factor cutoffs. Detailed knowledge of these geometric and sequence dependences should aid de novo design and prediction algorithms. PMID:21287621

Donald, Jason E.; Kulp, Daniel W.; DeGrado, William F.

2010-01-01

379

ON THE NONRELATIVISTIC ORIGIN OF RED-SKEWED IRON LINES IN CATACLYSMIC VARIABLE, NEUTRON STAR, AND BLACK HOLE SOURCES  

SciTech Connect

We perform the analysis of the iron K{sub {alpha}} lines detected in three sources representing three types of accreting compact sources: cataclysmic variable (CV) GK Per, neutron star (NS) Serpens X-1, and black hole (BH) GX 339-4. We find, using data from Epic-PN Camera onboard XMM-Newton observatory, that the iron K{sub {alpha}} emission line in GK Per has a noticeable red-skewed profile. We compare the GK Per asymmetric line with the red-skewed lines observed by XMM-Newton in Serpens X-1 and GX 339-4. The observation of the K{sub {alpha}} emission with red-skewed features in CV GK Per cannot be related to the redshift effects of General Relativity (GR). Therefore, if the mechanism of the K{sub {alpha}}-line formation is the same in CVs, NSs, and BHs then it is evident that the GR effects would be ruled out as a cause of red skewness of K{sub {alpha}} line. The line reprocessing in an outflowing wind has been recently suggested as an alternative model for a broad red-shifted iron line formation. In the framework of the outflow scenario the red-skewed iron line is formed in the strong extended wind due to its illumination by the radiation emanating from the innermost part of the accreting material. The outflow is a common phenomenon for CVs, NSs, and BHs. In this paper, we demonstrate that the asymmetric shapes of the lines detected from these CV, NS, and BH sources are well described with the wind (outflow) model. Furthermore we find by analyzing Rossi X-Ray Timing Explorer(RXTE) observations that when the strong red-skewed iron line is observed in GX 339-4 the high-frequency variability is strongly suppressed. While this fact is hard to reconcile with the relativistic models, it is consistent with the outflowing gas washing out high-frequency modulations of the radiation presumably originated in the innermost part of the source.

Titarchuk, Lev [George Mason University, Fairfax, VA 22030 (United States); Laurent, Philippe [CEA/DSM/DAPNIA/SAp, CEA Saclay, 91191 Gif sur Yvette (France); Shaposhnikov, Nikolai [University of Maryland, Astronomy Department, College Park, MD 20742 (United States)], E-mail: lev.titarchuk@nrl.navy.mil, E-mail: plaurent@cea.fr

2009-08-01

380

Network Bridging Potential in Later Life  

PubMed Central

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

Cornwell, Benjamin

2009-01-01

381

A comparison of bridging fault simulation methods  

Microsoft Academic Search

This study provides bridging fault simulation data obtained from the AMD-K6 microprocessor. It shows that: (1) high stuck-at fault coverage (99.5%) implies high bridging fault coverage; (2) coverage of a bridging fault by both wired-AND and wired-OR behavior does not guarantee detection of that fault when compared against a more accurate (transistor-level simulation) modeling method. A set of netname pairs

R. Scott Fetherston; Imtiaz P. Shaik; Siyad C. Ma

1999-01-01

382

Compressive VOF method with skewness correction to capture sharp interfaces on arbitrary meshes  

NASA Astrophysics Data System (ADS)

The accurate and efficient modelling of two-phase flows is at present mostly limited to structured, unskewed meshes, due to the additional topological and numerical complexity of arbitrary, unstructured meshes. Compressive VOF methods which discretize the interface advection with algebraic differencing schemes are computationally efficient and inherently applicable to arbitrary meshes. However, compressive VOF methods evidently suffer severely from numerical diffusion on meshes with topological skewness. In this paper we present a compressive VOF method using a state-of-the-art donor-acceptor advection scheme which includes novel modifications to substantially reduce numerical diffusion on arbitrary meshes without adding computational complexity. The new methodology accurately captures evolving interfaces on any arbitrary, non-overlapping mesh and conserves mass within the limits of the applied solver tolerance. A thorough validation of the presented methods is conducted, examining the pure advection of the interface indicator function as well as the application to evolving interfaces with surface tension. Crucially, the results on equidistant Cartesian and arbitrary tetrahedral meshes are shown to be comparable and accurate.

Denner, Fabian; van Wachem, Berend G. M.

2014-12-01

383

Inflammation-mediated Notch signaling skews Fanconi Anemia hematopoietic stem cell differentiation  

PubMed Central

Hematopoietic stem cells (HSCs) can either self-renew or differentiate into various types of cells of the blood lineage. Signaling pathways that regulate this choice of self-renewal versus differentiation are currently under extensive investigation. Here we report that deregulation of Notch signaling skews HSC differentiation in mouse models of Fanconi anemia (FA), a genetic disorder associated with bone marrow failure and progression to leukemia and other cancers. In mice expressing a transgenic Notch reporter, deletion of the Fanca or Fancc gene enhances Notch signaling in multipotential progenitors (MPPs), which is correlated with decreased phenotypic long-term HSCs and increased formation of MPP1 progenitors. Furthermore, we found an inverse correlation between Notch signaling and self-renewal capacity in FA hematopoietic stem and progenitor cells. Significantly, FA deficiency in MPPs deregulates a complex network of genes in the Notch and canonical NF-?B pathways. Genetic ablation or pharmacologic inhibition of NF-?B reduces Notch signaling in FA MPPs to near wide-type level, and blocking either NF-?B or Notch signaling partially restores FA HSC quiescence and self-renewal capacity. Taken together, these results suggest a functional crosstalk between Notch signaling and NF-?B pathway in regulation of HSC differentiation. PMID:23926327

Du, Wei; Amarachintha, Surya; Sipple, Jared; Schick, Jonathan; Steinbrecher, Kris; Pang, Qishen

2013-01-01

384

Effect of phase response curve skewness on synchronization of electrically coupled neuronal oscillators.  

PubMed

We investigate why electrically coupled neuronal oscillators synchronize or fail to synchronize using the theory of weakly coupled oscillators. Stability of synchrony and antisynchrony is predicted analytically and verified using numerical bifurcation diagrams. The shape of the phase response curve (PRC), the shape of the voltage time course, and the frequency of spiking are freely varied to map out regions of parameter spaces that hold stable solutions. We find that type 1 and type 2 PRCs can hold both synchronous and antisynchronous solutions, but the shape of the PRC and the voltage determine the extent of their stability. This is achieved by introducing a five-piecewise linear model to the PRC and a three-piecewise linear model to the voltage time course, and then analyzing the resultant eigenvalue equations that determine the stability of the phase-locked solutions. A single time parameter defines the skewness of the PRC, and another single time parameter defines the spike width and frequency. Our approach gives a comprehensive picture of the relation of the PRC shape, voltage time course, and stability of the resultant synchronous and antisynchronous solutions. PMID:23777519

Dodla, Ramana; Wilson, Charles J

2013-10-01

385

Skew of mantle upwelling beneath the East Pacific Rise governs segmentation.  

PubMed

Mantle upwelling is essential to the generation of new oceanic crust at mid-ocean ridges, and it is generally assumed that such upwelling is symmetric beneath active ridges. Here, however, we use seismic imaging to show that the isotropic and anisotropic structure of the mantle is rotated beneath the East Pacific Rise. The isotropic structure defines the pattern of magma delivery from the mantle to the crust. We find that the segmentation of the rise crest between transform faults correlates well with the distribution of mantle melt. The azimuth of seismic anisotropy constrains the direction of mantle flow, which is rotated nearly 10 degrees anticlockwise from the plate-spreading direction. The mismatch between the locus of mantle melt delivery and the morphologic ridge axis results in systematic differences between areas of on-axis and off-axis melt supply. We conclude that the skew of asthenospheric upwelling and transport governs segmentation of the East Pacific Rise and variations in the intensity of ridge crest processes. PMID:17377578

Toomey, Douglas R; Jousselin, David; Dunn, Robert A; Wilcock, William S D; Detrick, R S

2007-03-22

386

Failure detection and isolation investigation for strapdown skew redundant tetrad laser gyro inertial sensor arrays  

NASA Technical Reports Server (NTRS)

The degree to which flight-critical failures in a strapdown laser gyro tetrad sensor assembly can be isolated in short-haul aircraft after a failure occurrence has been detected by the skewed sensor failure-detection voting logic is investigated along with the degree to which a failure in the tetrad computer can be detected and isolated at the computer level, assuming a dual-redundant computer configuration. The tetrad system was mechanized with two two-axis inertial navigation channels (INCs), each containing two gyro/accelerometer axes, computer, control circuitry, and input/output circuitry. Gyro/accelerometer data is crossfed between the two INCs to enable each computer to independently perform the navigation task. Computer calculations are synchronized between the computers so that calculated quantities are identical and may be compared. Fail-safe performance (identification of the first failure) is accomplished with a probability approaching 100 percent of the time, while fail-operational performance (identification and isolation of the first failure) is achieved 93 to 96 percent of the time.

Eberlein, A. J.; Lahm, T. G.

1976-01-01

387

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

E-print Network

and build the Taylor "smart" Bridge utilizing fibre reinforced polymer (FRP) reinforcing materials, is considered to be the world's longest highway bridge with girders prestressed with FRP reinforcements and FRP

388

Figure 10: Kurtosis vs. Skewness vs. Coe cient of Variation, Rotated Ball Bearings at (0:52;0:88;3:19)  

E-print Network

Ball Bearings at (0:52;0:88;3:19)] 25 #12;0 0.5 1 1.5 CV 0 0.5 1 1.5 2 2.5 Skewness 0 5 10 15 Kurtosis. Coe cient of Variation Ball Bearings at (0:52;0:88;3:19)] 24 #12;0.5 1 1.5 2 2.5 3 Skewness0 2 4 6 8 Weibull Gamma Figure 7: Skewness vs. Coe cient of Variation Ball Bearings at (0:52;0:88)] 22 #12;0 50 100

Leemis, Larry

389

Finding bridges in packings of colloidal spheres  

E-print Network

We identify putative load-bearing structures (bridges) in experimental colloidal systems studied by confocal microscopy. Bridges are co-operative structures that have been used to explain stability and inhomogeneous force transmission in simulated granular packings with a range of densities. We show that bridges similar to those found in granular simulations are present in real experimental colloidal packings. We describe critically the bridge-finding procedure for real experimental data and propose a new criterion-Lowest Mean Squared Separation (LSQS)-for selecting optimum stabilisations.

Matthew C. Jenkins; Mark D. Haw; Gary C. Barker; Wilson C. K. Poon; Stefan U. Egelhaaf

2010-06-17

390

9. VIEW OF BRIDGE NEAR CENTER SPAN, LOOKING NORTH FROM ...  

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

9. VIEW OF BRIDGE NEAR CENTER SPAN, LOOKING NORTH FROM THE ARROYO SECO. THE PARKER-MAYBERRY BRIDGE IS BELOW THE COLORADO STREET BRIDGE, THE PIONEER BRIDGE IS IN THE BACKGROUND. - Colorado Street Bridge, Spanning Arroyo Seco at Colorado Boulevard, Pasadena, Los Angeles County, CA

391

3. CONTEXTUAL VIEW OF BRIDGE IN SETTING, LOOKING SOUTHWEST FROM ...  

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

3. CONTEXTUAL VIEW OF BRIDGE IN SETTING, LOOKING SOUTHWEST FROM ELEVATED GRADE OF EUREKA SOUTHERN RAILROAD. EUREKA SOUTHERN TRUSS BRIDGE AT EXTREME LEFT, 1924 HIGHWAY BRIDGE IN CENTER, 1952 HIGHWAY BRIDGE AT RIGHT - Van Duzen River Bridge, Spanning Van Duzen River at CA State Highway 101, Alton, Humboldt County, CA

392

Bridge Fault Simulation Strategies for CMOS Integrated Circuits Brian Chess  

E-print Network

circuit. The bridge fault transforms the two gates for which the bridged wires are outputs into a singleBridge Fault Simulation Strategies for CMOS Integrated Circuits Brian Chess Tracy Larrabee \\Lambda present a theorem for detecting feedback bridge faults. We discuss two different methods of bridge fault

Larrabee, Tracy

393

MULTI-HAZARD RESISTANT HIGHWAY BRIDGE PIERS HAVING  

E-print Network

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

Bruneau, Michel

394

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

E-print Network

) Co-sponsors are American Iron and Steel Institute (AISI) Bentley Systems, Inc. Canadian Institute but are considered formal addenda to the Rules. #12;4 Section 1 INTRODUCTION Students design and erect a steel bridge1 STUDENT STEEL BRIDGE COMPETITION 2012 RULES #12;2 MISSION The mission of the Student Steel Bridge

Duchowski, Andrew T.

395

Life-Cycle Cost Survey of Concrete Bridge Decks- A Benchmark for FRP Bridge Deck Replacement  

Microsoft Academic Search

A study on the life-cycle cost and performance of concrete bridge decks was conducted to establish a benchmark for fiber-reinforced polymer (FRP) bridge decks. A survey was developed and distributed to State Departments of Transportation engineers and the responses were analyzed. The survey facilitated identifying and estimating the cost parameters associated to concrete bridge deck replacement, and correlating cost with

Roberto Lopez-Anido

2001-01-01

396

Bridge afflux analysis through arched bridge constrictions using artificial intelligence methods  

Microsoft Academic Search

Although many studies have been carried out for estimating the afflux through modern straight deck bridge constrictions, little attention has been given to medieval arched bridge constrictions. Hydraulic Research Wallingford in the UK (Brown, P.M., 1988. Afflux at arch bridges. Report SR 182. Wallingford, UK: HR Wallingford) recently published a major coverage of both experimental and field afflux data obtained

Mustafa Mamak; Galip Seckin; Murat Cobaner; Ozgur Kisi

2009-01-01

397

Capacitance bridge measurements of magnetostriction  

NASA Astrophysics Data System (ADS)

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.

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

2002-05-01

398

Deletion Xq27.3q28 in female patient with global developmental delays and skewed X-inactivation  

PubMed Central

Background Global developmental delay and mental retardation are associated with X-linked disorders including Hunter syndrome (mucopolysaccharidosis type II) and Fragile X syndrome (FXS). Single nucleotide mutations in the iduronate 2-sulfatase (IDS) gene at Xq28 most commonly cause Hunter syndrome while a CGG expansion in the FMR1 gene at Xq27.3 is associated with Fragile X syndrome. Gene deletions of the Xq27-28 region are less frequently found in either condition with rare reports in females. Additionally, an association between Xq27-28 deletions and skewed X-inactivation of the normal X chromosome observed in previous studies suggested a primary role of the Xq27-28 region in X-inactivation. Case presentation We describe the clinical, molecular and biochemical evaluations of a four year-old female patient with global developmental delay and a hemizygous deletion of Xq27.3q28 (144,270,614-154,845,961 bp), a 10.6 Mb region that contains >100 genes including IDS and FMR1. A literature review revealed rare cases with similar deletions that included IDS and FMR1 in females with developmental delay, variable features of Hunter syndrome, and skewed X-inactivation of the normal X chromosome. In contrast, our patient exhibited skewed X-inactivation of the deleted X chromosome and tested negative for Hunter syndrome. Conclusions This is a report of a female with a 10.6 Mb Xq27-28 deletion with skewed inactivation of the deleted X chromosome. Contrary to previous reports, our observations do not support a primary role of the Xq27-28 region in X-inactivation. A review of the genes in the deletion region revealed several potential genes that may contribute to the patient’s developmental delays, and sequencing of the active X chromosome may provide insight into the etiology of this clinical presentation. PMID:23634718

2013-01-01

399

Flow Style Investigation and Noise Reduction of a Cross-Flow Fan with Varied Rotor-Skew-Angle Rotor  

Microsoft Academic Search

The purpose of this study was investigating the noise emission, flow-style, fan's performance regarding to cross-fan with three different rotor-skew angle (RSA) rotors. The special flow visualization setups for both vertical and parallel investigation of smoke slice were used to overcome the blind sight of a Laser-Doppler or a particle-tracking velocimeter, and the three-dimensional flow differences were confirmed with streamline

Go-Long Tsai; Tsung-Hsien Tu; Tung-Chen Li; Kuang-Hsieng Wang

2006-01-01

400

Validation of large eddy simulation method for study of flatness and skewness of decaying compressible magnetohydrodynamic turbulence  

Microsoft Academic Search

In the present work we study potential applicability of large eddy simulation (LES) method for prediction of flatness and\\u000a skewness of compressible magnetohydrodynamic (MHD) turbulence. The knowledge of these quantities characterizes non-Gaussian\\u000a properties of turbulence and can be used for verification of hypothesis on Gaussianity for the turbulent flow under consideration.\\u000a Prediction accuracy of these quantities by means of LES

Alexander A. Chernyshov; Kirill V. Karelsky; Arakel S. Petrosyan

2009-01-01

401

Salt-Bridge Energetics in Halophilic Proteins  

PubMed Central

Halophilic proteins have greater abundance of acidic over basic and very low bulky hydrophobic residues. Classical electrostatic stabilization was suggested as the key determinant for halophilic adaptation of protein. However, contribution of specific electrostatic interactions (i.e. salt-bridges) to overall stability of halophilic proteins is yet to be understood. To understand this, we use Adaptive-Poison-Boltzmann-Solver Methods along with our home-built automation to workout net as well as associated component energy terms such as desolvation energy, bridge energy and background energy for 275 salt-bridges from 20 extremely halophilic proteins. We then perform extensive statistical analysis on general and energetic attributes on these salt-bridges. On average, 8 salt-bridges per 150 residues protein were observed which is almost twice than earlier report. Overall contributions of salt-bridges are ?3.0 kcal mol?1. Majority (78%) of salt-bridges in our dataset are stable and conserved in nature. Although, average contributions of component energy terms are equal, their individual details vary greatly from one another indicating their sensitivity to local micro-environment. Notably, 35% of salt-bridges in our database are buried and stable. Greater desolvation penalty of these buried salt-bridges are counteracted by stable network salt-bridges apart from favorable equal contributions of bridge and background terms. Recruitment of extensive network salt-bridges (46%) with a net contribution of ?5.0 kcal mol?1 per salt-bridge, seems to be a halophilic design wherein favorable average contribution of background term (?10 kcal mol?1) exceeds than that of bridge term (?7 kcal mol?1). Interiors of proteins from halophiles are seen to possess relatively higher abundance of charge and polar side chains than that of mesophiles which seems to be satisfied by cooperative network salt-bridges. Overall, our theoretical analyses provide insight into halophilic signature in its specific electrostatic interactions which we hope would help in protein engineering and bioinformatics studies. PMID:24743799

Nayek, Arnab; Sen Gupta, Parth Sarthi; Banerjee, Shyamashree; Mondal, Buddhadev; Bandyopadhyay, Amal K.

2014-01-01

402

De novo MECP2 duplications in two females with intellectual disability and unfavorable complete skewed X-inactivation.  

PubMed

Xq28 microduplications of MECP2 are a prominent cause of a severe syndromic form of intellectual disability (ID) in males. Females are usually unaffected through near to complete X-inactivation of the aberrant X chromosome (skewing). In rare cases, affected females have been described due to random X-inactivation. Here, we report on two female patients carrying de novo MECP2 microduplications on their fully active X chromosomes. Both patients present with ID and additional clinical features. Mono-allelic expression confirmed complete skewing of X-inactivation. Consequently, significantly enhanced MECP2 mRNA levels were observed. We hypothesize that the cause for the complete skewing is due to a more harmful mutation on the other X chromosome, thereby forcing the MECP2 duplication to become active. However, we could not unequivocally identify such a second mutation by array-CGH or exome sequencing. Our data underline that, like in males, increased MECP2 dosage in females can contribute to ID too, which should be taken into account in diagnostics. PMID:25037250

Fieremans, Nathalie; Bauters, Marijke; Belet, Stefanie; Verbeeck, Jelle; Jansen, Anna C; Seneca, Sara; Roelens, Filip; De Baere, Elfride; Marynen, Peter; Froyen, Guy

2014-11-01

403

Smooth centile curves for skew and kurtotic data modelled using the Box-Cox power exponential distribution.  

PubMed

The Box-Cox power exponential (BCPE) distribution, developed in this paper, provides a model for a dependent variable Y exhibiting both skewness and kurtosis (leptokurtosis or platykurtosis). The distribution is defined by a power transformation Y(nu) having a shifted and scaled (truncated) standard power exponential distribution with parameter tau. The distribution has four parameters and is denoted BCPE (mu,sigma,nu,tau). The parameters, mu, sigma, nu and tau, may be interpreted as relating to location (median), scale (approximate coefficient of variation), skewness (transformation to symmetry) and kurtosis (power exponential parameter), respectively. Smooth centile curves are obtained by modelling each of the four parameters of the distribution as a smooth non-parametric function of an explanatory variable. A Fisher scoring algorithm is used to fit the non-parametric model by maximizing a penalized likelihood. The first and expected second and cross derivatives of the likelihood, with respect to mu, sigma, nu and tau, required for the algorithm, are provided. The centiles of the BCPE distribution are easy to calculate, so it is highly suited to centile estimation. This application of the BCPE distribution to smooth centile estimation provides a generalization of the LMS method of the centile estimation to data exhibiting kurtosis (as well as skewness) different from that of a normal distribution and is named here the LMSP method of centile estimation. The LMSP method of centile estimation is applied to modelling the body mass index of Dutch males against age. PMID:15351960

Rigby, Robert A; Stasinopoulos, D Mikis

2004-10-15

404

Politicizing NIH funding: a bridge to nowhere.  

PubMed

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

Epstein, Jonathan A

2011-09-01

405

Integral abutment bridge response under thermal loading  

Microsoft Academic Search

This paper presents a parametric study and approximate integral abutment bridge (IAB) response prediction models. IABs are complex structures due to the nonlinearity and uncertainties in bridge materials and soil boundaries. Current design specifications and guides do not provide clearly defined analysis methods; therefore, there is a need for easily implemented preliminary analysis and accurate two-dimensional (2D) analysis methods. Based

WooSeok Kim; Jeffrey A. Laman

2010-01-01

406

Small Schools: Bridging the Need for Community  

ERIC Educational Resources Information Center

This article describes the experience of teaching in a small school in New York City. It is observed that this offers opportunities for individuals to grow independently and to understand their impact on community and society. As they bridge the gap between becoming a teacher and understanding how to build bridges for children that are moving…

Hamilton, Greg

2005-01-01

407

Balsa Wood Bridge Competition Sponsored by  

E-print Network

capable of supporting a given load over a given span. The bridge must allow the passage of one Hot Wheel surface of the test supports. � The road surface is defined as the surface that will allow a Hot Wheel Car high wooden block. The Hot Wheel's car will be placed on the elevated portion of the bridge

Wang, Xiaorui "Ray"

408

Balsa Wood Bridge Competition Sponsored by  

E-print Network

capable of supporting a given load over a given span. The bridge must allow the passage of one Hot Wheel. · The road surface is defined as the surface that will allow a Hot Wheel Car to pass the length. However block. The Hot Wheel's car will be placed on the elevated portion of the bridge and will be allowed

Tennessee, University of

409

BEHAVIOUR OF BRIDGE DECKS REINFORCED BY GFRP  

E-print Network

-scale highway bridge deck model reinforced by glass fibre reinforced polymer (GFRP) reinforcements and tested of the reinforcement ratio and type of reinforcement on the behaviour ofbridge decks are presented. KEYWORDS: bridge structures subjected to aggressive environmental conditions is attributed to the corrosion of the steel

410

Bridges to Healthy Communities. AACC Project Brief.  

ERIC Educational Resources Information Center

The Bridges to Healthy Communities project assists community colleges in offering education and information services that help prevent HIV infection and other serious health problems in students. The five-year Bridges project emphasizes service learning as a community-building and intervention strategy for preventing HIV infection. This initiative…

Ottenritter, Nan; Barnett, Lynn

411

RELIABILITY ANALYSIS OF SUSPENSION BRIDGES AGAINST FLUTTER  

Microsoft Academic Search

A reliability analysis of suspension bridges against flutter failure is presented using the basic theory of reliability. For the purpose of analysis, uncertainties considered are those arising from the variations in geometric and mechanical properties of bridge, modelling, damping and experimentally obtained flutter derivatives. These uncertainties are incorporated by multiplying the computed flutter wind speed with a number of independent

S. Pourzeynali; T. K. DATTA

2002-01-01

412

Build and Test a Paper Bridge  

NSDL National Science Digital Library

In this hands-on activity, learners make a bridge out of a folded piece of paper and two blocks. Then they test their structure by stacking coins (and other things) on it, discovering how much weight the bridge can support before it collapses. This activity explores engineering, technology, architecture, weight, compression, tension, and balance.

Science, New Y.

1999-01-01

413

Bridges and the City: An Interdisciplinary Project.  

ERIC Educational Resources Information Center

Describes an interdisciplinary project to help elementary school children discover the relationship among technology, history, and geography that involved the building of a model Brooklyn Bridge and considering the history and role of the real bridge. Suggestions for similar projects for other cities are appended. (JPB)

Singer, Judith Y.; Goodman, Cecelia; Ridley, Theodora; Singer, Alan

2000-01-01

414

Simple Bridge for Pulsed Nuclear Magnetic Resonance  

Microsoft Academic Search

An asymmetrical rf bridge for pulsed magnetic resonance experiments is described. The balancing adjustments, which can be made quickly and easily, ensure a proper impedance match to transmitter and receiver. The bridge is particularly well suited for pure nuclear quadrupole resonance experiments.

K. R. Jeffrey; R. L. Armstrong

1967-01-01

415

Recent Innovation for Concrete Highway Bridges  

E-print Network

, Calgary, Alberta) is prestressed by carbon fiber reinforced plastic (CFRP) tendons and instrumented in Manitoba using straight and draped CFRP tendons for prestressing the girder, CFRP stirrups for shear reinforcement. CFRP for flexural reinforcement of the deck slab and GFRP for the bridge curbs. All bridges

416

THE BRIDGE COUPLING CAVITIES IN THE SEPARATED  

Microsoft Academic Search

The Separated Drift Tube Linac (SDTL) structure was pro- posed for medium energy range of proton linacs. The ac- celerating cavity consists of several SDTL units with fo- cusing lenses between sections. To drive several SDTL sections from single RF source, application of both RF power dividers and coupling bridge cavities seems feasible. Through bridge couplers, the field distribution, in

V. V. Paramonov; L. V. Kravchuk; A. S. Levchenko

417

BDES: A bridge design expert system  

Microsoft Academic Search

The expert system described here designs superstructures for small to medium span highway bridges. The system addresses a domain within the engineering design consultation paradigm. It is installed in a personal microcomputer environment. This paper examines the nature of the bridge design domain as practiced in the United States and its suitability for expert system application. The architecture, the context

Mrinmay Biswas; James G. Welch

1987-01-01

418

Teaching Elements and Principles of Bridge Design  

ERIC Educational Resources Information Center

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…

Beck, Charles

2005-01-01

419

A bridging model for parallel computation  

Microsoft Academic Search

The success of the von Neumann model of sequential computation is attributable to the fact that it is an efficient bridge between software and hardware: high-level languages can be efficiently compiled on to this model; yet it can be effeciently implemented in hardware. The author argues that an analogous bridge between software and hardware in required for parallel computation if

Leslie G. Valiant

1990-01-01

420

Resiliency of Bridges on the BOSFOLK Corridor.  

National Technical Information Service (NTIS)

Built with a design life of 50-years, many of the bridges on the Boston to Norfolk (BOSFOLK) corridor are nearing the end of their design life. Neglect, poor maintenance, and insufficient funding have left many of them in very bad condition. As the bridge...

H. W. Shenton, P. Seymour

2013-01-01

421

The adventures of the bridge jumper  

Microsoft Academic Search

Steve Brodie's 1886 jump from the Brooklyn Bridge created a particularly modern fame that has much to tell us about the emergence of modern media celebrity and the kinds of spectacular stunt performances that could be mobilised to create it in the years just before the cinema. Bridge jumpers such as Brodie took the modern urban landscape as their backdrop,

Jacob Smith

2010-01-01

422

Intergenerational and sibling conflict under patrilocality. A model of reproductive skew applied to human kinship.  

PubMed

Here we argue that models developed to examine cooperation and conflict in communal breeders, using a "tug-of-war" model of reproductive skew generated by incomplete control, are an appropriate way to model human kinship systems. We apply such models to understand the patterns of effort put into competition between father and son and between brothers in conflict over family resources in a patrilineal kinship system. Co-resident kin do not necessarily emerge with equal shares of the cake in terms of reproductive output. The models show that, depending on the efficiency with which they can gain more control of the resource, on the marriage system, and on the relatedness of the partners in conflict, individuals can do better to help their relatives breed rather than fight each other for the resources needed to reproduce. The models show that when a son's father is still breeding with his mother, sons should not compete for any share of reproduction. However, under polygyny, increased effort is spent on father/son and brother/brother conflict. Fathers will win the majority of reproduction if dominant to sons (in contrast to the finding that daughters-in-law win in conflict over mothers-in-law in patrilocal kinship systems, which has been suggested as explaining the evolution of menopause). Hence who wins in the sharing of reproduction depends not just on which sex disperses but also on the relative competitive ability of all individuals to exploit family resources. Anthropologists have long argued that cultural norms can reduce conflict. These formal evolutionary models help us to quantify the effects of reproductive conflict in families, throwing light on the evolutionary basis not just of patterns of reproductive scheduling, but also human kinship and marriage systems. PMID:24363047

Ji, Ting; Xu, Jing-Jing; Mace, Ruth

2014-03-01

423

An ancestral recombination graph for diploid populations with skewed offspring distribution.  

PubMed

A large offspring-number diploid biparental multilocus population model of Moran type is our object of study. At each time step, a pair of diploid individuals drawn uniformly at random contributes offspring to the population. The number of offspring can be large relative to the total population size. Similar "heavily skewed" reproduction mechanisms have been recently considered by various authors (cf. e.g., Eldon and Wakeley 2006, 2008) and reviewed by Hedgecock and Pudovkin (2011). Each diploid parental individual contributes exactly one chromosome to each diploid offspring, and hence ancestral lineages can coalesce only when in distinct individuals. A separation-of-timescales phenomenon is thus observed. A result of Möhle (1998) is extended to obtain convergence of the ancestral process to an ancestral recombination graph necessarily admitting simultaneous multiple mergers of ancestral lineages. The usual ancestral recombination graph is obtained as a special case of our model when the parents contribute only one offspring to the population each time. Due to diploidy and large offspring numbers, novel effects appear. For example, the marginal genealogy at each locus admits simultaneous multiple mergers in up to four groups, and different loci remain substantially correlated even as the recombination rate grows large. Thus, genealogies for loci far apart on the same chromosome remain correlated. Correlation in coalescence times for two loci is derived and shown to be a function of the coalescence parameters of our model. Extending the observations by Eldon and Wakeley (2008), predictions of linkage disequilibrium are shown to be functions of the reproduction parameters of our model, in addition to the recombination rate. Correlations in ratios of coalescence times between loci can be high, even when the recombination rate is high and sample size is large, in large offspring-number populations, as suggested by simulations, hinting at how to distinguish between different population models. PMID:23150600

Birkner, Matthias; Blath, Jochen; Eldon, Bjarki

2013-01-01

424

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

425

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

426

15. View of Tombigbee River Bridge facing same direction as ...  

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

15. View of Tombigbee River Bridge facing same direction as in photograph no. MS-13-14 except this view is the underside of the bridge. - Tombigbee River Bridge, Spanning Tombigbee River at State Highway 182, Columbus, Lowndes County, MS

427

7. View of Tombigbee River Bridge facing just right on ...  

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

7. View of Tombigbee River Bridge facing just right on view shown in photograph no. MS-13-G. New bridge is partially shown in the background. - Tombigbee River Bridge, Spanning Tombigbee River at State Highway 182, Columbus, Lowndes County, MS

428

13. Fourth Melan Bridge on tour route, Union Avenue near ...  

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

13. Fourth Melan Bridge on tour route, Union Avenue near bust of General John Thayer, elevation detail view to the north. - Vicksburg National Military Park Roads & Bridges, Melan Arch Bridges, Spanning various tributaries at Confederate Avenue, Vicksburg, Warren County, MS

429

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

430

Aeroelastic Analysis of Bridges: Effects of Turbulence and Aerodynamic Nonlinearities  

E-print Network

by utilizing an example of a long span suspension bridge with aerodynamic characteristics sensitiveAeroelastic Analysis of Bridges: Effects of Turbulence and Aerodynamic Nonlinearities Xinzhong Chen for capturing the emerging concerns in bridge aerodynamics introduced by aerodynamic nonlinearities

Kareem, Ahsan

431

9. View of bridge looking west. A fundraising marathon is ...  

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

9. View of bridge looking west. A fund-raising marathon is in prgress. The traffic levels outside the main arch were added in 1965 when the bridge underwent extensive rehabilitation. - Detroit Superior High Level Bridge, Cleveland, Cuyahoga County, OH

432

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

433

1. Photocopy from George S. Morison's The Plattsmouth Bridge, 1882. ...  

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

1. Photocopy from George S. Morison's The Plattsmouth Bridge, 1882. Photographer unknown, circa 1880. SOUTH WEB AND WEST PORTAL OF BRIDGE - Plattsmouth Bridge, Spanning Missouri River, Plattsmouth, Cass County, NE

434

1. Photocopy from George S. Morison's The Sioux City Bridge, ...  

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

1. Photocopy from George S. Morison's The Sioux City Bridge, 1890. Photographer unknown, circa 1889. SOUTH WEB AND WEST PORTAL OF BRIDGE - Sioux City Bridge, Spanning the Missouri River, Sioux City, Woodbury County, IA

435

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

436

General perspective view of the North Fork Butter Creek Bridge, ...  

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

General perspective view of the North Fork Butter Creek Bridge, view looking north - North Fork Butter Creek Bridge, Spanning North Fork Butter Creek Bridge at Milepost 76.63 on Heppner Highway (Oregon Route 74), Pilot Rock, Umatilla County, OR

437

Approach view of the North Fork Butter Creek Bridge, view ...  

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

Approach view of the North Fork Butter Creek Bridge, view looking north - North Fork Butter Creek Bridge, Spanning North Fork Butter Creek Bridge at Milepost 76.63 on Heppner Highway (Oregon Route 74), Pilot Rock, Umatilla County, OR

438

Elevation view of the North Fork Butter Creek Bridge, view ...  

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

Elevation view of the North Fork Butter Creek Bridge, view looking west - North Fork Butter Creek Bridge, Spanning North Fork Butter Creek Bridge at Milepost 76.63 on Heppner Highway (Oregon Route 74), Pilot Rock, Umatilla County, OR

439

General perspective view of the North Fork Butter Creek Bridge, ...  

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

General perspective view of the North Fork Butter Creek Bridge, view looking south - North Fork Butter Creek Bridge, Spanning North Fork Butter Creek Bridge at Milepost 76.63 on Heppner Highway (Oregon Route 74), Pilot Rock, Umatilla County, OR

440

General perspective view of the North Fork Butter Creek Bridge, ...  

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

General perspective view of the North Fork Butter Creek Bridge, view looking southwest - North Fork Butter Creek Bridge, Spanning North Fork Butter Creek Bridge at Milepost 76.63 on Heppner Highway (Oregon Route 74), Pilot Rock, Umatilla County, OR

441

Approach view of the North Fork Butter Creek Bridge, view ...  

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

Approach view of the North Fork Butter Creek Bridge, view looking south - North Fork Butter Creek Bridge, Spanning North Fork Butter Creek Bridge at Milepost 76.63 on Heppner Highway (Oregon Route 74), Pilot Rock, Umatilla County, OR

442

Detail perspective view of the North Fork Butter Creek Bridge, ...  

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

Detail perspective view of the North Fork Butter Creek Bridge, view looking southwest - North Fork Butter Creek Bridge, Spanning North Fork Butter Creek Bridge at Milepost 76.63 on Heppner Highway (Oregon Route 74), Pilot Rock, Umatilla County, OR

443

GENERAL VIEW LOOKING WEST SHOWING LIFT BRIDGE. COUNTER WEIGHTS ARE ...  

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

GENERAL VIEW LOOKING WEST SHOWING LIFT BRIDGE. COUNTER WEIGHTS ARE LARGE SQUARES VISIBLE ABOVE BRIDGE - New York, New Haven & Hartford Railroad, Fort Point Channel Rolling Lift Bridge, Spanning Fort Point Channel, Boston, Suffolk County, MA

444

3. GENERAL VIEW LOOKING WEST, SHOWING LIFT BRIDGE. COUNTER WEIGHTS ...  

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

3. GENERAL VIEW LOOKING WEST, SHOWING LIFT BRIDGE. COUNTER WEIGHTS ARE LARGE SQUARES VISIBLE ABOVE BRIDGE. - New York, New Haven & Hartford Railroad, Fort Point Channel Rolling Lift Bridge, Spanning Fort Point Channel, Boston, Suffolk County, MA

445

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

446

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

447

Contextual view from First Street Bridge, showing Los Angeles River ...  

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

Contextual view from First Street Bridge, showing Los Angeles River and context of Fourth Street Bridge, facing south - First Street Bridge, Spanning Los Angeles River at First Street, Los Angeles, Los Angeles County, CA

448

29 CFR 1917.124 - Dockboards (car and bridge plates).  

... 2014-07-01 false Dockboards (car and bridge plates). 1917.124 Section...Facilities § 1917.124 Dockboards (car and bridge plates). (a) General... (b) [Reserved] (c) Dockboards (car and bridge plates). (1)...

2014-07-01

449

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

450

49 CFR 237.51 - Railroad bridge engineers.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Railroad bridge engineers. 237.51 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and...Responsible Persons § 237.51 Railroad bridge engineers. (a) A railroad...

2011-10-01

451

23 CFR 650.307 - Bridge inspection organization.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 2013-04-01 false Bridge inspection organization. 650.307 Section...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS National Bridge Inspection Standards § 650.307...

2013-04-01

452

23 CFR 650.705 - Application for discretionary bridge funds.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Application for discretionary bridge funds. 650.705 Section 650.705...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Discretionary Bridge Candidate Rating Factor § 650.705...

2013-04-01

453

23 CFR 650.809 - Movable span bridges.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 false Movable span bridges. 650.809 Section 650.809 Highways... ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.809 Movable span...

2013-04-01

454

46 CFR 108.801 - Navigation bridge visibility.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Navigation bridge visibility. 108.801 Section 108.801...DRILLING UNITS DESIGN AND EQUIPMENT Navigation Bridge Visibility § 108.801 Navigation bridge visibility. Each mobile offshore...

2013-10-01

455

49 CFR 237.51 - Railroad bridge engineers.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Railroad bridge engineers. 237.51 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and...Responsible Persons § 237.51 Railroad bridge engineers. (a) A railroad...

2013-10-01

456

29 CFR 1917.124 - Dockboards (car and bridge plates).  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Dockboards (car and bridge plates). 1917.124 Section 1917... § 1917.124 Dockboards (car and bridge plates). (a) General. The...Reserved] (c) Dockboards (car and bridge plates). (1) Dockboards shall...

2011-07-01

457

23 CFR 650.307 - Bridge inspection organization.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 2011-04-01 false Bridge inspection organization. 650.307 Section...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS National Bridge Inspection Standards § 650.307...

2011-04-01

458

23 CFR 650.307 - Bridge inspection organization.  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 2012-04-01 false Bridge inspection organization. 650.307 Section...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS National Bridge Inspection Standards § 650.307...

2012-04-01

459

49 CFR 236.766 - Locking, movable bridge.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Locking, movable bridge. 236.766 Section 236.766 Transportation... Definitions § 236.766 Locking, movable bridge. The rail locks, bridge locks, bolt locks, circuit controllers,...

2012-10-01

460

23 CFR 650.307 - Bridge inspection organization.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 2010-04-01 false Bridge inspection organization. 650.307 Section...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS National Bridge Inspection Standards § 650.307...

2010-04-01

461

33 CFR 115.70 - Advance approval of bridges.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Advance approval of bridges. 115.70 Section 115.70 Navigation and Navigable...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE...

2012-07-01

462

49 CFR 237.31 - Adoption of bridge management programs.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Adoption of bridge management programs. 237.31 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Railroad Bridge Safety Assurance § 237.31 Adoption of...

2013-10-01

463

21 CFR 872.3770 - Temporary crown and bridge resin.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770...Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2013-04-01

464

46 CFR 92.03-1 - Navigation bridge visibility.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Navigation bridge visibility. 92.03-1 Section 92.03-1... CONSTRUCTION AND ARRANGEMENT Navigation Bridge Visibility § 92.03-1 Navigation bridge visibility. Each cargo and...

2012-10-01

465

49 CFR 237.55 - Railroad bridge supervisors.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Railroad bridge supervisors. 237.55 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and...Responsible Persons § 237.55 Railroad bridge supervisors. A railroad...

2011-10-01

466

23 CFR 650.809 - Movable span bridges.  

Code of Federal Regulations, 2010 CFR

... 2010-04-01 false Movable span bridges. 650.809 Section 650.809 Highways... ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.809 Movable span...

2010-04-01

467

49 CFR 237.55 - Railroad bridge supervisors.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Railroad bridge supervisors. 237.55 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and...Responsible Persons § 237.55 Railroad bridge supervisors. A railroad...

2010-10-01

468

29 CFR 1917.124 - Dockboards (car and bridge plates).  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Dockboards (car and bridge plates). 1917.124 Section 1917... § 1917.124 Dockboards (car and bridge plates). (a) General. The...Reserved] (c) Dockboards (car and bridge plates). (1) Dockboards shall...

2012-07-01

469

23 CFR 650.409 - Evaluation of bridge inventory.  

...2014-04-01 2014-04-01 false Evaluation of bridge inventory. 650.409 Section 650.409...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Highway Bridge Replacement and Rehabilitation Program...

2014-04-01

470

21 CFR 872.3770 - Temporary crown and bridge resin.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770...Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2010-04-01

471

33 CFR 115.70 - Advance approval of bridges.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Advance approval of bridges. 115.70 Section 115.70 Navigation and Navigable...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE...

2011-07-01

472

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 ...Systems § 112.43-7 Navigating bridge distribution panel. (a) Except...a distribution panel on the navigating bridge: (1) Navigation lights not...

2012-10-01

473

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 ...Systems § 112.43-7 Navigating bridge distribution panel. (a) Except...a distribution panel on the navigating bridge: (1) Navigation lights not...

2013-10-01

474

33 CFR 118.100 - Retroreflective panels on bridge piers.  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Retroreflective panels on bridge piers. 118.100 Section 118.100 Navigation...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.100...

2010-07-01

475

23 CFR 650.409 - Evaluation of bridge inventory.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Evaluation of bridge inventory. 650.409 Section 650.409...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Highway Bridge Replacement and Rehabilitation Program...

2011-04-01

476

49 CFR 237.55 - Railroad bridge supervisors.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Railroad bridge supervisors. 237.55 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and...Responsible Persons § 237.55 Railroad bridge supervisors. A railroad...

2013-10-01

477

33 CFR 118.100 - Retroreflective panels on bridge piers.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Retroreflective panels on bridge piers. 118.100 Section 118.100 Navigation...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.100...

2013-07-01

478

49 CFR 237.31 - Adoption of bridge management programs.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Adoption of bridge management programs. 237.31 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Railroad Bridge Safety Assurance § 237.31 Adoption of...

2012-10-01

479

23 CFR 650.409 - Evaluation of bridge inventory.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Evaluation of bridge inventory. 650.409 Section 650.409...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Highway Bridge Replacement and Rehabilitation Program...

2012-04-01

480

23 CFR 650.409 - Evaluation of bridge inventory.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Evaluation of bridge inventory. 650.409 Section 650.409...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Highway Bridge Replacement and Rehabilitation Program...

2013-04-01

481

49 CFR 237.55 - Railroad bridge supervisors.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Railroad bridge supervisors. 237.55 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and...Responsible Persons § 237.55 Railroad bridge supervisors. A railroad...

2012-10-01

482

23 CFR 650.409 - Evaluation of bridge inventory.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Evaluation of bridge inventory. 650.409 Section 650.409...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Highway Bridge Replacement and Rehabilitation Program...

2010-04-01

483

23 CFR 650.705 - Application for discretionary bridge funds.  

...2014-04-01 false Application for discretionary bridge funds. 650.705 Section 650.705...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Discretionary Bridge Candidate Rating Factor § 650.705...

2014-04-01

484

21 CFR 872.3770 - Temporary crown and bridge resin.  

...2014-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770...Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2014-04-01

485

23 CFR 650.705 - Application for discretionary bridge funds.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Application for discretionary bridge funds. 650.705 Section 650.705...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Discretionary Bridge Candidate Rating Factor § 650.705...

2012-04-01

486

23 CFR 650.307 - Bridge inspection organization.  

... 2014-04-01 2014-04-01 false Bridge inspection organization. 650.307 Section...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS National Bridge Inspection Standards § 650.307...

2014-04-01

487

33 CFR 164.15 - Navigation bridge visibility.  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Navigation bridge visibility. 164.15 Section 164...REGULATIONS § 164.15 Navigation bridge visibility. (a) The arrangement...the field of vision from the navigation bridge conforms as closely as possible to...

2012-07-01

488

46 CFR 72.04-1 - Navigation bridge visibility.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Navigation bridge visibility. 72.04-1 Section 72.04-1... CONSTRUCTION AND ARRANGEMENT Navigation Bridge Visibility § 72.04-1 Navigation bridge visibility. Each passenger vessel...

2013-10-01

489

33 CFR 115.70 - Advance approval of bridges.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Advance approval of bridges. 115.70 Section 115.70 Navigation and Navigable...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE...

2010-07-01

490

49 CFR 237.33 - Content of bridge management programs.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Content of bridge management programs. 237.33 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Railroad Bridge Safety Assurance § 237.33 Content of...

2013-10-01

491

23 CFR 650.705 - Application for discretionary bridge funds.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Application for discretionary bridge funds. 650.705 Section 650.705...TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Discretionary Bridge Candidate Rating Factor § 650.705...

2011-04-01

492

23 CFR 650.809 - Movable span bridges.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 false Movable span bridges. 650.809 Section 650.809 Highways... ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.809 Movable span...

2011-04-01

493

49 CFR 237.51 - Railroad bridge engineers.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Railroad bridge engineers. 237.51 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and...Responsible Persons § 237.51 Railroad bridge engineers. (a) A railroad...

2012-10-01

494

49 CFR 237.33 - Content of bridge management programs.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Content of bridge management programs. 237.33 Section 237...ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Railroad Bridge Safety Assurance § 237.33 Content of...

2011-10-01

495

29 CFR 1917.124 - Dockboards (car and bridge plates).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Dockboards (car and bridge plates). 1917.124 Section 1917... § 1917.124 Dockboards (car and bridge plates). (a) General. The...Reserved] (c) Dockboards (car and bridge plates). (1) Dockboards shall...

2013-07-01

496

49 CFR 237.101 - Scheduling of bridge inspections.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Scheduling of bridge inspections. 237.101 Section 237.101 ...RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Bridge Inspection § 237.101 Scheduling of...

2011-10-01

497

49 CFR 236.766 - Locking, movable bridge.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Locking, movable bridge. 236.766 Section 236.766 Transportation... Definitions § 236.766 Locking, movable bridge. The rail locks, bridge locks, bolt locks, circuit controllers,...

2011-10-01

498

46 CFR 92.03-1 - Navigation bridge visibility.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Navigation bridge visibility. 92.03-1 Section 92.03-1... CONSTRUCTION AND ARRANGEMENT Navigation Bridge Visibility § 92.03-1 Navigation bridge visibility. Each cargo and...

2013-10-01

499

33 CFR 118.100 - Retroreflective panels on bridge piers.  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Retroreflective panels on bridge piers. 118.100 Section 118.100 Navigation...Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.100...

2012-07-01

500

21 CFR 872.3770 - Temporary crown and bridge resin.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Temporary crown and bridge resin. 872.3770 Section 872.3770...Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a...

2012-04-01