WorldWideScience

Sample records for bridge substructures

  1. Effect of Soil-Structure Interaction on Seismic Performance of Long-Span Bridge Tested by Dynamic Substructuring Method

    Directory of Open Access Journals (Sweden)

    Zhenyun Tang

    2017-01-01

    Full Text Available Because of the limitations of testing facilities and techniques, the seismic performance of soil-structure interaction (SSI system can only be tested in a quite small scale model in laboratory. Especially for long-span bridge, a smaller tested model is required when SSI phenomenon is considered in the physical test. The scale effect resulting from the small scale model is always coupled with the dynamic performance, so that the seismic performance of bridge considering SSI effect cannot be uncovered accurately by the traditional testing method. This paper presented the implementation of real-time dynamic substructuring (RTDS, involving the combined use of shake table array and computational engines for the seismic simulation of SSI. In RTDS system, the bridge with soil-foundation system is divided into physical and numerical substructures, in which the bridge is seen as physical substructures and the remaining part is seen as numerical substructures. The interface response between the physical and numerical substructures is imposed by shake table and resulting reaction force is fed back to the computational engine. The unique aspect of the method is to simulate the SSI systems subjected to multisupport excitation in terms of a larger physical model. The substructuring strategy and the control performance associated with the real-time substructuring testing for SSI were performed. And the influence of SSI on a long-span bridge was tested by this novel testing method.

  2. Thermal substructure of hot deformed austenite substructure

    Energy Technology Data Exchange (ETDEWEB)

    Bernshtejn, M.L.; Kaputkina, L.M.; Nikishov, N.A. (Moskovskij Inst. Stali i Splavov (USSR))

    1982-01-01

    Effect of hot working different regimes on formation of austenite structure and substructure of the 60N20 and 60Kh5G6 steels and kinetics of softening processes at postdeformation isothermal (at deformation temperature) heating, is investigated. It is shown, that variation of hot working regimes permits to obtain a wide range of structural and substructural austenite conditions. Rate decrease and temperature increase promotes obtaining after hot working and conservation under cooling conditions of developed polygonized substructure. Similar polygonized isotropic substructure with a rather low density of dislocations inside of subgrains promotes decelerating of initial stages of recrystallization development under conditions of hot working and regulated post-deformation heatings. Alloying by carbide-forming elements (chromium and manganese) delays development of recrystallization (in comparison with alloying with nickel), even if the steel is in the condition of single-phase solid solution.

  3. Jet substructure in ATLAS

    CERN Document Server

    Miller, David W

    2011-01-01

    Measurements are presented of the jet invariant mass and substructure in proton-proton collisions at $\\sqrt{s} = 7$ TeV with the ATLAS detector using an integrated luminosity of 37 pb$^{-1}$. These results exercise the tools for distinguishing the signatures of new boosted massive particles in the hadronic final state. Two "fat" jet algorithms are used, along with the filtering jet grooming technique that was pioneered in ATLAS. New jet substructure observables are compared for the first time to data at the LHC. Finally, a sample of candidate boosted top quark events collected in the 2010 data is analyzed in detail for the jet substructure properties of hadronic "top-jets" in the final state. These measurements demonstrate not only our excellent understanding of QCD in a new energy regime but open the path to using complex jet substructure observables in the search for new physics.

  4. 桥梁下部结构裂缝提取的改进C-V模型算法%Modified C-V model algorithm of crack extraction for bridge substructure

    Institute of Scientific and Technical Information of China (English)

    李刚; 贺拴海; 杜凯; 刘伟; 杜秦文

    2012-01-01

    应用改进C-V模型,进行桥梁下部结构裂缝图像分割,通过裂缝截取、图像填充和旋转变换精确提取裂缝宽度。对不同光照条件下拍摄的在役混凝土桥梁结构裂缝图像,分别利用改进C-V模型算法、自适应阈值法、形态学算法、C-V模型以及Canny算法进行试验对比。分析结果表明:改进C-V模型算法误分率和运算时间最小,分别为3.02%与89ms;1 000幅桥梁结构裂缝图像试验对比显示裂缝检测准确率大于90.8%,裂缝宽度平均误差小于0.03mm。可见,改进算法可有效提高检测准确率,减少运算时间。%The crack image segmentation of bridge substructure was studied by utilizing a modified C-V model. Crack clip, image filling and rotation transformation were applied for the precise extraction of crack width. The crack images of existing concrete bridge structure were taken in different illuminations, and test results were compared by using modified C-V model algorithm, adaptive threshold algorithm, morphology algorithm, C-V model and Canny algorithm. Analysis result indicates that the miselassification rate of modified C-V model algorithm is 3.02%, the operation time is 89 ms, and the values are minimum compared with other methods. Based on the comparative test on 1 000 crack images of bridge structure, the accuracy rate of crack detection is greater than 90.8%, and the mean error of crack width is less than 0.03 mm. So the modified algorithm can effectively improve detection accuracy rate, and reduce operation time. 2 tabs, 6 figs, 16 refs.

  5. Jet Substructure Without Trees

    Energy Technology Data Exchange (ETDEWEB)

    Jankowiak, Martin; Larkoski, Andrew J.; /SLAC /Stanford U., ITP

    2011-08-19

    We present an alternative approach to identifying and characterizing jet substructure. An angular correlation function is introduced that can be used to extract angular and mass scales within a jet without reference to a clustering algorithm. This procedure gives rise to a number of useful jet observables. As an application, we construct a top quark tagging algorithm that is competitive with existing methods. In preparation for the LHC, the past several years have seen extensive work on various aspects of collider searches. With the excellent resolution of the ATLAS and CMS detectors as a catalyst, one area that has undergone significant development is jet substructure physics. The use of jet substructure techniques, which probe the fine-grained details of how energy is distributed in jets, has two broad goals. First, measuring more than just the bulk properties of jets allows for additional probes of QCD. For example, jet substructure measurements can be compared against precision perturbative QCD calculations or used to tune Monte Carlo event generators. Second, jet substructure allows for additional handles in event discrimination. These handles could play an important role at the LHC in discriminating between signal and background events in a wide variety of particle searches. For example, Monte Carlo studies indicate that jet substructure techniques allow for efficient reconstruction of boosted heavy objects such as the W{sup {+-}} and Z{sup 0} gauge bosons, the top quark, and the Higgs boson.

  6. Jet Substructure by Accident

    CERN Document Server

    Cohen, Timothy; Lisanti, Mariangela; Lou, Hou Keong

    2012-01-01

    We propose a new search strategy for high-multiplicity hadronic final states. When new particles are produced at threshold, the distribution of their decay products is approximately isotropic. If there are many partons in the final state, it is likely that several will be clustered into the same large-radius jet. The resulting jet exhibits substructure, even though the parent states are not boosted. This "accidental" substructure is a powerful discriminant against background because it is more pronounced for high-multiplicity signals than for QCD multijets. We demonstrate how to take advantage of accidental substructure to reduce backgrounds without relying on the presence of missing energy. As an example, we present the expected limits for several R-parity violating gluino decay topologies. This approach allows for the determination of QCD backgrounds using data-driven methods, which is crucial for the feasibility of any search that targets signatures with many jets and suppressed missing energy.

  7. Substructural Identification of Flexural Rigidity for Beam-Like Structures

    Directory of Open Access Journals (Sweden)

    Ki-Young Koo

    2015-01-01

    Full Text Available This study proposes a novel substructural identification method based on the Bernoulli-Euler beam theory with a single variable optimization scheme to estimate the flexural rigidity of a beam-like structure such as a bridge deck, which is one of the major structural integrity indices of a structure. In ordinary bridges, the boundary condition of a superstructure can be significantly altered by aging and environmental variations, and the actual boundary conditions are generally unknown or difficult to be estimated correctly. To efficiently bypass the problems related to boundary conditions, a substructural identification method is proposed to evaluate the flexural rigidity regardless of the actual boundary conditions by isolating an identification region within the internal substructure. The proposed method is very simple and effective as it utilizes the single variable optimization based on the transfer function formulated utilizing Bernoulli Euler beam theory for the inverse analysis to obtain the flexural rigidity. This novel method is also rigorously investigated by applying it for estimating the flexural rigidity of a simply supported beam model with different boundary conditions, a concrete plate-girder bridge model with different length of an internal substructure, a cantilever-type wind turbine tower structure with different type of excitation, and a steel box-girder bridge model with internal structural damages.

  8. The Cluster Substructure - Alignment Connection

    OpenAIRE

    Plionis, Manolis

    2001-01-01

    Using the APM cluster data we investigate whether the dynamical status of clusters is related to the large-scale structure of the Universe. We find that cluster substructure is strongly correlated with the tendency of clusters to be aligned with their nearest neighbour and in general with the nearby clusters that belong to the same supercluster. Furthermore, dynamically young clusters are more clustered than the overall cluster population. These are strong indications that cluster develop in ...

  9. Substructure mining using elaborate chemical representation.

    Science.gov (United States)

    Kazius, Jeroen; Nijssen, Siegfried; Kok, Joost; Bäck, Thomas; Ijzerman, Adriaan P

    2006-01-01

    Substructure mining algorithms are important drug discovery tools since they can find substructures that affect physicochemical and biological properties. Current methods, however, only consider a part of all chemical information that is present within a data set of compounds. Therefore, the overall aim of our study was to enable more exhaustive data mining by designing methods that detect all substructures of any size, shape, and level of chemical detail. A means of chemical representation was developed that uses atomic hierarchies, thus enabling substructure mining to consider general and/or highly specific features. As a proof-of-concept, the efficient, multipurpose graph mining system Gaston learned substructures of any size and shape from a mutagenicity data set that was represented in this manner. From these substructures, we extracted a set of only six nonredundant, discriminative substructures that represent relevant biochemical knowledge. Our results demonstrate the individual and synergistic importance of elaborate chemical representation and mining for nonlinear substructures. We conclude that the combination of elaborate chemical representation and Gaston provides an excellent method for 2D substructure mining as this recipe systematically explores all substructures in different levels of chemical detail.

  10. Chemical substructure analysis in toxicology

    Energy Technology Data Exchange (ETDEWEB)

    Beauchamp, R.O. Jr. [Center for Information on Toxicology and Environment, Raleigh, NC (United States)

    1990-12-31

    A preliminary examination of chemical-substructure analysis (CSA) demonstrates the effective use of the Chemical Abstracts compound connectivity file in conjunction with the bibliographic file for relating chemical structures to biological activity. The importance of considering the role of metabolic intermediates under a variety of conditions is illustrated, suggesting structures that should be examined that may exhibit potential activity. This CSA technique, which utilizes existing large files accessible with online personal computers, is recommended for use as another tool in examining chemicals in drugs. 2 refs., 4 figs.

  11. Mass Substructure in Abell 3128

    Science.gov (United States)

    McCleary, J.; dell'Antonio, I.; Huwe, P.

    2015-05-01

    We perform a detailed two-dimensional weak gravitational lensing analysis of the nearby (z = 0.058) galaxy cluster Abell 3128 using deep ugrz imaging from the Dark Energy Camera (DECam). We have designed a pipeline to remove instrumental artifacts from DECam images and stack multiple dithered observations without inducing a spurious ellipticity signal. We develop a new technique to characterize the spatial variation of the point-spread function that enables us to circularize the field to better than 0.5% and thereby extract the intrinsic galaxy ellipticities. By fitting photometric redshifts to sources in the observation, we are able to select a sample of background galaxies for weak-lensing analysis free from low-redshift contaminants. Photometric redshifts are also used to select a high-redshift galaxy subsample with which we successfully isolate the signal from an interloping z = 0.44 cluster. We estimate the total mass of Abell 3128 by fitting the tangential ellipticity of background galaxies with the weak-lensing shear profile of a Navarro-Frenk-White (NFW) halo and also perform NFW fits to substructures detected in the 2D mass maps of the cluster. This study yields one of the highest resolution mass maps of a low-z cluster to date and is the first step in a larger effort to characterize the redshift evolution of mass substructures in clusters.

  12. MASS SUBSTRUCTURE IN ABELL 3128

    Energy Technology Data Exchange (ETDEWEB)

    McCleary, J.; Dell’Antonio, I.; Huwe, P., E-mail: Jacqueline_McCleary@brown.edu [Department of Physics, Brown University, Box 1843, Providence, RI 02912 (United States)

    2015-05-20

    We perform a detailed two-dimensional weak gravitational lensing analysis of the nearby (z = 0.058) galaxy cluster Abell 3128 using deep ugrz imaging from the Dark Energy Camera (DECam). We have designed a pipeline to remove instrumental artifacts from DECam images and stack multiple dithered observations without inducing a spurious ellipticity signal. We develop a new technique to characterize the spatial variation of the point-spread function that enables us to circularize the field to better than 0.5% and thereby extract the intrinsic galaxy ellipticities. By fitting photometric redshifts to sources in the observation, we are able to select a sample of background galaxies for weak-lensing analysis free from low-redshift contaminants. Photometric redshifts are also used to select a high-redshift galaxy subsample with which we successfully isolate the signal from an interloping z = 0.44 cluster. We estimate the total mass of Abell 3128 by fitting the tangential ellipticity of background galaxies with the weak-lensing shear profile of a Navarro–Frenk–White (NFW) halo and also perform NFW fits to substructures detected in the 2D mass maps of the cluster. This study yields one of the highest resolution mass maps of a low-z cluster to date and is the first step in a larger effort to characterize the redshift evolution of mass substructures in clusters.

  13. Evolution variable dependence of jet substructure

    CERN Document Server

    Sakaki, Yasuhito

    2015-01-01

    Studies on jet substructure have evolved significantly in recent years. Jet substructure is essentially determined by QCD radiations and non-perturbative effects. Predictions of jet substructure are usually different among Monte Carlo event generators, and are governed by the parton shower algorithm implemented. For leading logarithmic parton shower, even though one of the core variables is the evolution variable, its choice is not unique. We examine evolution variable dependence of the jet substructure by developing a parton shower generator that interpolates between different evolution variables using a parameter $\\alpha$. Jet shape variables and associated jet rates for quark and gluon jets are used to demonstrate the $\\alpha$-dependence of the jet substructure. We find angular ordered shower predicts wider jets, while relative transverse momentum ($p_{\\bot}$) ordered shower predicts narrower jets. This is qualitatively in agreement with the missing phase space of $p_{\\bot}$ ordered showers. Such differenc...

  14. Optical Substructures in 48 Galaxy Clusters

    CERN Document Server

    Girardi, M; Fadda, D; Giuricin, G; Mardirossian, F; Mezzetti, M

    1996-01-01

    We analyze the presence of substructures in a set of 48 galaxy clusters, by using galaxy positions and redshifts. We use a multi-scale analysis which couples kinematical estimators with the wavelet transform. 14% of our clusters are strongly substructured (i.e. they are bimodal or complex) and 24% of the remaining unimodal clusters contain substructures at small scales. Thus, in substantial agreement with previous studies, about one third of clusters show substructures. In unimodal clusters the presence of substructures does not affect the estimates of both virial masses and velocity dispersions, which are generally in good agreement with the X-ray temperatures. Thus, unimodal clusters are not too far from a status of dynamical equilibrium. On the contrary, velocity dispersions and masses for some bimodal or complex clusters strongly depend on whether they are treated as single systems or as sums of different clumps and X-ray temperatures and velocity dispersions may be very different.

  15. Bridge engineering handbook construction and maintenance

    CERN Document Server

    Chen, Wai-Fah

    2014-01-01

    Over 140 experts, 14 countries, and 89 chapters are represented in the second edition of the Bridge Engineering Handbook. This extensive collection highlights bridge engineering specimens from around the world, contains detailed information on bridge engineering, and thoroughly explains the concepts and practical applications surrounding the subject.Published in five books: Fundamentals, Superstructure Design, Substructure Design, Seismic Design, and Construction and Maintenance, this new edition provides numerous worked-out examples that give readers step-by-step design procedures, includes c

  16. Type Classes for Lightweight Substructural Types

    Directory of Open Access Journals (Sweden)

    Edward Gan

    2015-02-01

    Full Text Available Linear and substructural types are powerful tools, but adding them to standard functional programming languages often means introducing extra annotations and typing machinery. We propose a lightweight substructural type system design that recasts the structural rules of weakening and contraction as type classes; we demonstrate this design in a prototype language, Clamp. Clamp supports polymorphic substructural types as well as an expressive system of mutable references. At the same time, it adds little additional overhead to a standard Damas-Hindley-Milner type system enriched with type classes. We have established type safety for the core model and implemented a type checker with type inference in Haskell.

  17. Chemical substructure search in SQL.

    Science.gov (United States)

    Golovin, Adel; Henrick, Kim

    2009-01-01

    We present a novel technique for a fast chemical substructure search on a relational database by use of a standard SQL query. The symmetry of a query graph is analyzed to give additional constraints. Our method is based on breadth-first search (BFS) algorithms implementation using Relational Database Management Systems (RDBMS). In addition to the chemical search we apply our technique to the field of intermolecular interactions which involves nonplanar graphs and describe how to achieve linear time performance along with the suggestion on how to sufficiently reduce the linear coefficient. From the algorithms theory perspective these results mean that subgraph isomorphism is a polynomial time problem, hence equal problems have the same complexity. The application to subgraph isomorphism in chemical search is available at http://www.ebi.ac.uk/msd-srv/chemsearch and http://www.ebi.ac.uk/msd-srv/msdmotif/chem . The application to the network of molecule interactions is available at http://www.ebi.ac.uk/msd-srv/msdmotif .

  18. Algebraic sub-structuring for electromagnetic applications

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chao; Gao, Weiguo; Bai, Zhaojun; Li, Xiaoye; Lee, Lie-Quan; Husbands, Parry; Ng, Esmond G.

    2004-09-14

    Algebraic sub-structuring refers to the process of applying matrix reordering and partitioning algorithms to divide a large sparse matrix into smaller submatrices from which a subset of spectral components are extracted and combined to form approximate solutions to the original problem. In this paper, we show that algebraic sub-structuring can be effectively used to solve generalized eigenvalue problems arising from the finite element analysis of an accelerator structure.

  19. Algebraic Sub-Structuring for Electromagnetic Applications

    Energy Technology Data Exchange (ETDEWEB)

    Yang, C.; Gao, W.G.; Bai, Z.J.; Li, X.Y.S.; Lee, L.Q.; Husbands, P.; Ng, E.G.; /LBL, Berkeley /UC, Davis /SLAC

    2006-06-30

    Algebraic sub-structuring refers to the process of applying matrix reordering and partitioning algorithms to divide a large sparse matrix into smaller submatrices from which a subset of spectral components are extracted and combined to form approximate solutions to the original problem. In this paper, they show that algebraic sub-structuring can be effectively used to solve generalized eigenvalue problems arising from the finite element analysis of an accelerator structure.

  20. A structural design decomposition method utilizing substructuring

    Science.gov (United States)

    Scotti, Stephen J.

    1994-01-01

    A new method of design decomposition for structural analysis and optimization is described. For this method, the structure is divided into substructures where each substructure has its structural response described by a structural-response subproblem, and its structural sizing determined from a structural-sizing subproblem. The structural responses of substructures that have rigid body modes when separated from the remainder of the structure are further decomposed into displacements that have no rigid body components, and a set of rigid body modes. The structural-response subproblems are linked together through forces determined within a structural-sizing coordination subproblem which also determines the magnitude of any rigid body displacements. Structural-sizing subproblems having constraints local to the substructures are linked together through penalty terms that are determined by a structural-sizing coordination subproblem. All the substructure structural-response subproblems are totally decoupled from each other, as are all the substructure structural-sizing subproblems, thus there is significant potential for use of parallel solution methods for these subproblems.

  1. The Singular Behavior of Jet Substructure Observables

    CERN Document Server

    Larkoski, Andrew J

    2016-01-01

    Jet substructure observables play a central role at the Large Hadron Collider for identifying the boosted hadronic decay products of electroweak scale resonances. The complete description of these observables requires understanding both the limit in which hard substructure is resolved, as well as the limit of a jet with a single hard core. In this paper we study in detail the perturbative structure of two prominent jet substructure observables, $N$-subjettiness and the energy correlation functions, as measured on background QCD jets. In particular, we focus on the distinction between the limits in which two-prong structure is resolved or unresolved. Depending on the choice of subjet axes, we demonstrate that at fixed order, $N$-subjettiness can manifest myriad behaviors in the unresolved region: smooth tails, end-point singularities, or singularities in the physical region. The energy correlation functions, by contrast, only have non-singular perturbative tails extending to the end point. We discuss the effec...

  2. Halo Substructure Towards the Galactic Center

    Science.gov (United States)

    Amy, Paul Martin; Martin, Charles; Newberg, Heidi Jo; Shelton, Siddartha; Carlin, Jeffrey L.; Willett, Benjamin A.

    2017-01-01

    We measure the velocity substructure of blue horizontal branch stars in Data Release 10 of the Sloan Digital Sky Survey, particularly in the regions of the Hermus Stream, the Hyllus Stream, and the Hercules-Aquila Cloud. These stars are concentrated at lower latitudes (b Research.

  3. MAPPING THE GALACTIC HALO. VIII. QUANTIFYING SUBSTRUCTURE

    NARCIS (Netherlands)

    Starkenburg, Else; Helmi, Amina; Morrison, Heather L.; Harding, Paul; van Woerden, Hugo; Mateo, Mario; Olszewski, Edward W.; Sivarani, Thirupathi; Norris, John E.; Freeman, Kenneth C.; Shectman, Stephen A.; Dohm-Palmer, R. C.; Frey, Lucy; Oravetz, Dan

    2009-01-01

    We have measured the amount of kinematic substructure in the Galactic halo using the final data set from the Spaghetti project, a pencil-beam high-latitude sky survey. Our sample contains 101 photometrically selected and spectroscopically confirmed giants with accurate distance, radial velocity, and

  4. THE UNORTHODOX ORBITS OF SUBSTRUCTURE HALOS

    NARCIS (Netherlands)

    Ludlow, Aaron D.; Navarro, Julio F.; Springel, Volker; Jenkins, Adrian; Frenk, Carlos S.; Helmi, Amina

    2009-01-01

    We use a suite of cosmological N-body simulations to study the properties of substructure halos (subhalos) in galaxy-sized cold dark matter halos. We extend prior work on the subject by considering the whole population of subhalos physically associated with the main system. These are defined as subh

  5. Boosted objects and jet substructure at the LHC

    CERN Document Server

    Altheimer, A.; Asquith, L.; Backus Mayes, J.; Bergeaas Kuutmann, E.; Berger, J.; Bjergaard, D.; Bryngemark, L.; Buckley, A.; Butterworth, J.; Cacciari, M.; Campanelli, M.; Carli, T.; Chala, M.; Chen, C.; Chou, J.P.; Cornelissen, Th.; Curtin, D.; Dasgupta, M.; Davison, A.; De Almeida Dias, F.; De Cosa, A.; De Roeck, A.; Debenedetti, C.; Doglioni, C.; Ellis, S.D.; Fassi, F.; Ferrando, J.; Fleischmann, S.; Freytsis, M.; Gonzalez Silva, M.L.; Gonzalez de la Hoz, S.; Guescini, F.; Han, Z.; Hook, A.; Hornig, A.; Izaguirre, E.; Jankowiak, M.; Juknevich, J.; Kaci, M.; Kar, D.; Kasieczka, G.; Kogler, R.; Larkoski, A.; Loch, P.; Lopez Mateos, D.; Marzani, S.; Masetti, L.; Mateu, V.; Miller, D.W.; Mishra, K.; Nef, P.; Nordstrom, K.; Oliver Garcia, E.; Penwell, J.; Pilot, J.; Plehn, T.; Rappoccio, S.; Rizzi, A.; Rodrigo, G.; Safonov, A.; Salam, G.P.; Salt, J.; Schaetzel, S.; Schioppa, M.; Schmidt, A.; Scholtz, J.; Schwartzman, A.; Schwartz, M.; Segala, M.; Son, M.; Soyez, G.; Spannowsky, M.; Stewart, I.; Strom, D.; Swiatlowski, M.; Sanchez Martinez, V.; Takeuchi, M.; Thaler, J.; Thompson, E.; Tran, N.V.; Vermilion, C.; Villaplana, M.; Vos, M.; Wacker, J.; Walsh, J.

    2014-01-01

    This report of the BOOST2012 workshop presents the results of four working groups that studied key aspects of jet substructure. We discuss the potential of the description of jet substructure in first-principle QCD calculations and study the accuracy of state-of-the-art Monte Carlo tools. Experimental limitations of the ability to resolve substructure are evaluated, with a focus on the impact of additional proton proton collisions on jet substructure performance in future LHC operating scenarios. A final section summarizes the lessons learnt during the deployment of substructure analyses in searches for new physics in the production of boosted top quarks.

  6. THE ORIGIN OF THE VIRGO STELLAR SUBSTRUCTURE

    Energy Technology Data Exchange (ETDEWEB)

    Carlin, Jeffrey L.; Yam, William; Willett, Benjamin A.; Newberg, Heidi J. [Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY 12180 (United States); Casetti-Dinescu, Dana I.; Girard, Terrence M. [Astronomy Department, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States); Majewski, Steven R., E-mail: carlij@rpi.edu [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States)

    2012-07-10

    We present three-dimensional space velocities of stars selected to be consistent with membership in the Virgo stellar substructure. Candidates were selected from SA 103, a single 40' Multiplication-Sign 40' field from our proper-motion (PM) survey in Kapteyn's Selected Areas (SAs), based on the PMs, Sloan Digital Sky Survey (SDSS) photometry, and follow-up spectroscopy of 215 stars. The signature of the Virgo substructure is clear in the SDSS color-magnitude diagram (CMD) centered on SA 103, and 16 stars are identified that have high Galactocentric-frame radial velocities (V{sub GSR} > 50 km s{sup -1}) and lie near the CMD locus of Virgo. The implied distance to the Virgo substructure from the candidates is 14 {+-} 3 kpc. We derive mean kinematics from these 16 stars, finding a radial velocity V{sub GSR} = 153 {+-} 22 km s{sup -1} and proper motions ({mu}{sub {alpha}}cos {delta}, {mu}{sub {delta}}) = (- 5.24, -0.91) {+-} (0.43, 0.46) mas yr{sup -1}. From the mean kinematics of these members, we determine that the Virgo progenitor was on an eccentric (e {approx} 0.8) orbit that recently passed near the Galactic center (pericentric distance R{sub p} {approx} 6 kpc). This destructive orbit is consistent with the idea that the substructure(s) in Virgo originated in the tidal disruption of a Milky Way satellite. N-body simulations suggest that the entire cloud-like Virgo substructure (encompassing the 'Virgo Overdensity' and the 'Virgo Stellar Stream') is likely the tidal debris remnant from a recently disrupted massive ({approx}10{sup 9} M{sub Sun }) dwarf galaxy. The model also suggests that some other known stellar overdensities in the Milky Way halo (e.g., the Pisces Overdensity and debris near NGC 2419 and SEGUE 1) are explained by the disruption of the Virgo progenitor.

  7. An online substructure identification method for local structural health monitoring

    Science.gov (United States)

    Hou, Jilin; Jankowski, Łukasz; Ou, Jinping

    2013-09-01

    This paper proposes a substructure isolation method, which uses time series of measured local response for online monitoring of substructures. The proposed monitoring process consists of two key steps: construction of the isolated substructure, and its identification. The isolated substructure is an independent virtual structure, which is numerically isolated from the global structure by placing virtual supports on the interface. First, the isolated substructure is constructed by a specific linear combination of time series of its measured local responses. Then, the isolated substructure is identified using its local natural frequencies extracted from the combined responses. The substructure is assumed to be linear; the outside part of the global structure can have any characteristics. The method has no requirements on the initial state of the structure, and so the process can be carried out repetitively for online monitoring. Online isolation and monitoring is illustrated in a numerical example with a frame model, and then verified in a cantilever beam experiment.

  8. Smart variations: Functional substructures for part compatibility

    KAUST Repository

    Zheng, Youyi

    2013-05-01

    As collections of 3D models continue to grow, reusing model parts allows generation of novel model variations. Naïvely swapping parts across models, however, leads to implausible results, especially when mixing parts across different model families. Hence, the user has to manually ensure that the final model remains functionally valid. We claim that certain symmetric functional arrangements (sFarr-s), which are special arrangements among symmetrically related substructures, bear close relation to object functions. Hence, we propose a purely geometric approach based on such substructures to match, replace, and position triplets of parts to create non-trivial, yet functionally plausible, model variations. We demonstrate that starting even from a small set of models such a simple geometric approach can produce a diverse set of non-trivial and plausible model variations. © 2013 The Author(s) Computer Graphics Forum © 2013 The Eurographics Association and Blackwell Publishing Ltd.

  9. Towards an understanding of jet substructure

    CERN Document Server

    Dasgupta, Mrinal; Marzani, Simone; Salam, Gavin P

    2013-01-01

    We present first analytic, resummed calculations of the rates at which widespread jet substructure tools tag QCD jets. As well as considering trimming, pruning and the mass-drop tagger, we introduce modified tools with improved analytical and phenomenological behaviours. Most taggers have double logarithmic resummed structures. The modified mass-drop tagger is special in that it involves only single logarithms, and is free from a complex class of terms known as non-global logarithms. The modification of pruning brings an improved ability to discriminate between the different colour structures that characterise signal and background. As we outline in an extensive phenomenological discussion, these results provide valuable insight into the performance of existing tools and help lay robust foundations for future substructure studies.

  10. Tagging Partially Reconstructed Objects with Jet Substructure

    CERN Document Server

    Freytsis, Marat; Walsh, Jonathan R

    2014-01-01

    We present a new tagger which aims at identifying partially reconstructed objects, in which only some of the constituents are collected in a single jet. As an example, we focus on top decays in which either part of the hadronically decaying W or the b jet is soft or falls outside of the top jet cone. We construct an observable to identify remnant substructure from the decay and employ aggressive jet grooming to reject QCD backgrounds. The tagger is complementary to existing ones and works well in the intermediate boost regime where jet substructure techniques usually fail. It is anticipated that a similar tagger can be used to identify non-QCD hadronic jets, such as those expected from hidden valleys.

  11. Simulations of substructures in relativistic jets

    CERN Document Server

    Garcia, R O

    2016-01-01

    We present a set of simulations of relativistic jets from accretion disk initial setup with a new code in Fortran 90 to get numerical solutions of a system of General Relativistic Magnetohydrodynamics (GRMHD) partial differential equations in a fixed Black Hole (BH) spacetime which is able to show substructures formations inside the jet as well as a lobe formation on the disk. For this, a central scheme of finite volume method without dimensional split and no Riemann solvers (a Nessyahu-Tadmor method) was implemented. Thus, we were able to obtain stable numerical solutions with spurious oscillations under control and no excessive numerical dissipation. We setup a magnetized accretion disk uncharged plasma surrounding a central Schwarzschild BH immersed in a magnetosphere which evolve to the ejection of matter in the form of jet with its substructures over a distance of almost twenty times the BH radius.

  12. The Origin of the Virgo Stellar Substructure

    CERN Document Server

    Carlin, Jeffrey L; Casetti-Dinescu, Dana I; Willett, Benjamin A; Newberg, Heidi J; Majewski, Steven R; Girard, Terrence M

    2012-01-01

    We present three-dimensional space velocities of stars selected to be consistent with membership in the Virgo stellar substructure. Candidates were selected from SA 103, a single 40x40 arcmin field from our proper motion (PM) survey in Kapteyn's Selected Areas (SAs), based on the PMs, SDSS photometry, and follow-up spectroscopy of 215 stars. The signature of the Virgo substructure is clear in the SDSS color-magnitude diagram (CMD) centered on SA 103, and 16 stars are identified that have high Galactocentric-frame radial velocities (V_GSR > 50 km/s) and lie near the CMD locus of Virgo. The implied distance to the Virgo substructure from the candidates is 14+/-3 kpc. We derive mean kinematics from these 16 stars, finding a radial velocity V_GSR = 153+/-22 km/s and proper motions (mu_alpha*cos(delta), mu_delta) = (-5.24, -0.91)+/-(0.43, 0.46) mas/yr. From the mean kinematics of these members, we determine that the Virgo progenitor was on an eccentric (e ~ 0.8) orbit that recently passed near the Galactic center ...

  13. Identifying a new particle with jet substructures

    CERN Document Server

    Lim, Sung Hak; Kim, Doojin; Kim, Minho; Kong, Kyoungchul; Park, Myeonghun

    2017-01-01

    We investigate a potential of measuring properties of a heavy resonance X, exploiting jet substructure techniques. Motivated by heavy higgs boson searches, we focus on the decays of X into a pair of (massive) electroweak gauge bosons. More specifically, we consider a hadronic Z boson, which makes it possible to determine properties of X at an earlier stage. For $m_X$ of O(1) TeV, two quarks from a Z boson would be captured as a "merged jet" in a significant fraction of events. The use of the merged jet enables us to consider a Z-induced jet as a reconstructed object without any combinatorial ambiguity. We apply a conventional jet substructure method to extract four-momenta of subjets from a merged jet. We find that jet substructure procedures may enhance features in some kinematic observables formed with subjets. Subjet momenta are fed into the matrix element associated with a given hypothesis on the nature of X, which is further processed to construct a matrix element method (MEM)-based observable. For both ...

  14. Composite Octet Searches with Jet Substructure

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Yang; /SLAC; Shelton, Jessie; /Yale U.

    2012-02-14

    Many new physics models with strongly interacting sectors predict a mass hierarchy between the lightest vector meson and the lightest pseudoscalar mesons. We examine the power of jet substructure tools to extend the 7 TeV LHC sensitivity to these new states for the case of QCD octet mesons, considering both two gluon and two b-jet decay modes for the pseudoscalar mesons. We develop both a simple dijet search using only the jet mass and a more sophisticated jet substructure analysis, both of which can discover the composite octets in a dijet-like signature. The reach depends on the mass hierarchy between the vector and pseudoscalar mesons. We find that for the pseudoscalar-to-vector meson mass ratio below approximately 0.2 the simple jet mass analysis provides the best discovery limit; for a ratio between 0.2 and the QCD-like value of 0.3, the sophisticated jet substructure analysis has the best discovery potential; for a ratio above approximately 0.3, the standard four-jet analysis is more suitable.

  15. Simulations of Strong Gravitational Lensing with Substructure

    CERN Document Server

    Amara, A; Cox, T J; Ostriker, J P; Amara, Adam; Cox, Thomas J.; Ostriker, Jeremiah P.

    2004-01-01

    Galactic sized gravitational lenses are simulated by combining a cosmological N-body simulation and models for the baryonic component of the galaxy. The lens caustics, critical curves, image locations and magnification ratios are calculated by ray-shooting on an adaptive grid. It is found that the simulations do not cause the observed number of violations of the cusp caustic magnification relation. A part of this may be due to an insufficient amount of substructure but even for unsmoothed simulations (with maximal substructure) the factor of three increase in the number of violations still did not match the data. This suggests that other factors play an important role. These may include lensing by structure outside the halo, selection bias and the possibility that a randomly selected galaxy halo may be more irregular, for example due to recent mergers, than the isolated halo used in this study. It is also shown that, with the computed level of substructure, the image magnifications of the Einstein cross type ...

  16. Identifying a new particle with jet substructures

    CERN Document Server

    Lim, Sung Hak; Kim, Doojin; Kim, Minho; Kong, Kyoungchul; Park, Myeonghun

    2016-01-01

    We investigate a potential of measuring properties of a heavy resonance X, exploiting jet substructure techniques. Motivated by heavy higgs boson searches, we focus on the decays of X into a pair of (massive) electroweak gauge bosons. More specifically, we consider a hadronic Z boson, which makes it possible to determine properties of X at an earlier stage. For $m_X$ of O(1) TeV, two quarks from a Z boson would be captured as a "merged jet" in a significant fraction of events. The use of the merged jet enables us to consider a Z-induced jet as a reconstructed object without any combinatorial ambiguity. We apply a conventional jet substructure method to extract four-momenta of subjets from a merged jet. We find that jet substructure procedures may enhance features in some kinematic observables formed with subjets. Subjet momenta are fed into the matrix element associated with a given hypothesis on the nature of X, which is further processed to construct a matrix element method (MEM)-based observable. For both ...

  17. Frost Resistance and Permeability of Cement Stabilized Gravel used as Filling Material for Pearl-Chain Bridges

    DEFF Research Database (Denmark)

    Lund, Mia Schou Møller; Hansen, Kurt Kielsgaard; Hertz, Kristian Dahl

    2014-01-01

    The Pearl-Chain Bridge Technology introduces a new innovative arch bridge solution which com-bines the statical advantages of an arch bridge with a minimum of traffic disturbance. The arch-shaped substructure is stabilized by a filling material, e.g. cement stabilized gravel, which should meet...... higher for a cement content of 4% compared to 5%....

  18. Free-Interface Modal Synthesis Based Substructural Damage Detection Method

    Directory of Open Access Journals (Sweden)

    Shanghong Chen

    2014-01-01

    Full Text Available Free-interface modal synthesis method is applied to civil structure, and a substructure method is proposed by introducing the method into global sensitivity method. The substructure expression of the derivatives of eigenvalues and eigenvectors with respect to elemental parameters is obtained. The accuracy of the application of free-interface modal synthesis method is evaluated with different retained modes in substructure, and then the effectiveness of the proposed substructure sensitivity method is illustrated through an 11-storey building under both single- and multidamage cases. Both the damage locations and the extent can be effectively identified. By comparing it with the identical results of global sensitivity method, the proposed method can be faster in detecting the damage location and more stable under multidamage cases. Since this substructure sensitivity method only needs to update sensitivity matrix in the substructure with relative small number of DOFs, it may save much computation effort and become more efficient.

  19. Railroad Bridges

    Data.gov (United States)

    Department of Homeland Security — Bridges-Rail in the United States According to The National Bridge Inspection Standards published in the Code of Federal Regulations (23 CFR 650.3), a bridge isA...

  20. Structural integrity of Offshore Wind Power Substructures

    OpenAIRE

    Imafidon, Oliver Osazee

    2010-01-01

    Offshore wind turbine structures are now being developed in relatively deep waters with the purpose of capturing and utilizing the strong winds at sea. The structures must be robust in order to resist extreme loads. To be competitive, a cost reduction in fabrication and installation of wind substructures is necessary and the use of high strength steel has been suggested as one way of achieving this through the design of light-weight structures.The thesis gives an overview of offshore wind tur...

  1. Substructurability: the effect of interface location on a real-time dynamic substructuring test

    Science.gov (United States)

    Terkovics, N.; Neild, S. A.; Lowenberg, M.; Szalai, R.; Krauskopf, B.

    2016-08-01

    A full-scale experimental test for large and complex structures is not always achievable. This can be due to many reasons, the most prominent one being the size limitations of the test. Real-time dynamic substructuring is a hybrid testing method where part of the system is modelled numerically and the rest of the system is kept as the physical test specimen. The numerical-physical parts are connected via actuators and sensors and the interface is controlled by advanced algorithms to ensure that the tested structure replicates the emulated system with sufficient accuracy. The main challenge in such a test is to overcome the dynamic effects of the actuator and associated controller, that inevitably introduce delay into the substructured system which, in turn, can destabilize the experiment. To date, most research concentrates on developing control strategies for stable recreation of the full system when the interface location is given a priori. Therefore, substructurability is mostly studied in terms of control. Here, we consider the interface location as a parameter and study its effect on the stability of the system in the presence of delay due to actuator dynamics and define substructurability as the system's tolerance to delay in terms of the different interface locations. It is shown that the interface location has a major effect on the tolerable delays in an experiment and, therefore, careful selection of it is necessary.

  2. Substructure method in high-speed monorail dynamic problems

    Science.gov (United States)

    Ivanchenko, I. I.

    2008-12-01

    equations. This approach permits studying the stress-strain state in the MTET system and determining accelerations at the desired points of the rolling stock. The proposed numerical procedure permits uniquely solving linear and nonlinear differential equations describing the operation of the model, which replaces the system by a monorail rolling stock consisting of several specialized mutually connected cars and a system of continuous beams on elastic inertial supports. This approach (based on the use of a moving substructure, which is also modeled by a system of boundary rod elements) permits maximally reducing the number of unknowns in the resolving system of equations at each step of its solution [11]. The authors of the preceding investigations of this problem, when studying the simultaneous vibrations of bridges and moving loads, considered only the case in which the rolling stock was represented by sufficiently complicated systems of rigid bodies connected by viscoelastic links [3-18] and the rolling stock motion was described by systems of ordinary differential equations. A specific characteristic of the proposed method is that it is convenient to derive the equations of motion of both the rolling stock and the bridge structure. The method [9, 14] permits obtaining the equations of interaction between the structures as two separate finite-element structures. Hence the researcher need not traditionally write out the system of equations of motion, for example, for the rolling stock (of cars) with finitely many degrees of freedom [3-18].We note several papers where simultaneous vibrations of an elastic moving load and an elastic carrying structure are considered in a rather narrow region and have a specific character. For example, the motion of an elastic rod along an elastic infinite rod on an elastic foundation is studied in [20], and the body of a car moving along a beam is considered as a rod with ten concentrated masses in [21].

  3. Identifying a New Particle with Jet Substructures

    CERN Document Server

    Han, Chengcheng; Kim, Minho; Kong, Kyoungchul; Lim, Sung Hak; Park, Myeonghun

    2016-01-01

    We investigate a potential of determining properties of a new heavy resonance of mass $\\mathcal{O}(1)$ TeV which decays to collimated jets via heavy Standard Model intermediary states, exploiting jet substructure techniques. Employing the $Z$ gauge boson as a concrete example for the intermediary state, we utilize a ``merged jet'' defined by a large jet size to capture the two quarks from its decay. The use of the merged jet benefits the identification of a $Z$-induced jet as a single, reconstructed object without any combinatorial ambiguity. We find that jet substructure procedures may enhance features in some kinematic observables formed with subjet four-momenta extracted from a merged jet. This observation motivates us to feed subjet momenta into the matrix elements associated with plausible hypotheses on the nature of the heavy resonance, which are further processed to construct a matrix element method (MEM)-based observable. For both moderately and highly boosted $Z$ bosons, we demonstrate that the ME...

  4. Substructure of fuzzy dark matter halos

    CERN Document Server

    Du, Xiaolong; Niemeyer, Jens C

    2016-01-01

    We derive the halo mass function (HMF) for fuzzy dark matter (FDM) by solving the excursion set problem explicitly with a mass-dependent barrier function, which has not been done before. We find that compared to the naive approach of the Sheth-Tormen HMF for FDM the one we obtain has a higher cut off mass and the cut off mass change less strongly with redshifts. Using merger trees constructed with a modified version of the Lacey & Cole formalism that accounts for suppressed small scale power and the scale-dependent growth of FDM halos and the semi-analytic Galacticus code, we study the statistics of halo substructure including the effects from dynamical friction and tidal stripping. We find that if the dark matter is a mixture of cold dark matter (CDM) and FDM, there will be a suppression on the halo substructure on small scales which may be able to solve the Missing Satellites Problem faced by the pure CDM model. The suppression becomes stronger with increasing FDM fraction or decreasing FDM mass. Thus i...

  5. Early dynamical evolution of young substructured clusters

    Science.gov (United States)

    Dorval, Julien; Boily, Christian

    2017-03-01

    Stellar clusters form with a high level of substructure, inherited from the molecular cloud and the star formation process. Evidence from observations and simulations also indicate the stars in such young clusters form a subvirial system. The subsequent dynamical evolution can cause important mass loss, ejecting a large part of the birth population in the field. It can also imprint the stellar population and still be inferred from observations of evolved clusters. Nbody simulations allow a better understanding of these early twists and turns, given realistic initial conditions. Nowadays, substructured, clumpy young clusters are usually obtained through pseudo-fractal growth and velocity inheritance. We introduce a new way to create clumpy initial conditions through a ''Hubble expansion'' which naturally produces self consistent clumps, velocity-wise. In depth analysis of the resulting clumps shows consistency with hydrodynamical simulations of young star clusters. We use these initial conditions to investigate the dynamical evolution of young subvirial clusters. We find the collapse to be soft, with hierarchical merging leading to a high level of mass segregation. The subsequent evolution is less pronounced than the equilibrium achieved from a cold collapse formation scenario.

  6. Cold Dark Matter Substructure and Galactic Disks

    CERN Document Server

    Kazantzidis, Stelios; Bullock, James S

    2008-01-01

    We perform a set of high-resolution, dissipationless N-body simulations to investigate the influence of cold dark matter (CDM) substructure on the dynamical evolution of thin galactic disks. Our method combines cosmological simulations of galaxy-sized CDM halos to derive the properties of substructure populations and controlled numerical experiments of consecutive subhalo impacts onto initially-thin, fully-formed disk galaxies. We demonstrate that close encounters between massive subhalos and galactic disks since z~1 should be common occurrences in LCDM models. In contrast, extremely few satellites in present-day CDM halos are likely to have a significant impact on the disk structure. One typical host halo merger history is used to seed controlled N-body experiments of subhalo-disk encounters. As a result of these accretion events, the disk thickens considerably at all radii with the disk scale height increasing in excess of a factor of 2 in the solar neighborhood. We show that interactions with the subhalo p...

  7. Substructure of fuzzy dark matter haloes

    Science.gov (United States)

    Du, Xiaolong; Behrens, Christoph; Niemeyer, Jens C.

    2017-02-01

    We derive the halo mass function (HMF) for fuzzy dark matter (FDM) by solving the excursion set problem explicitly with a mass-dependent barrier function, which has not been done before. We find that compared to the naive approach of the Sheth-Tormen HMF for FDM, our approach has a higher cutoff mass and the cutoff mass changes less strongly with redshifts. Using merger trees constructed with a modified version of the Lacey & Cole formalism that accounts for suppressed small-scale power and the scale-dependent growth of FDM haloes and the semi-analytic GALACTICUS code, we study the statistics of halo substructure including the effects from dynamical friction and tidal stripping. We find that if the dark matter is a mixture of cold dark matter (CDM) and FDM, there will be a suppression on the halo substructure on small scales which may be able to solve the missing satellites problem faced by the pure CDM model. The suppression becomes stronger with increasing FDM fraction or decreasing FDM mass. Thus, it may be used to constrain the FDM model.

  8. Safety Evaluation of a Hybrid Substructure for Offshore Wind Turbine

    Directory of Open Access Journals (Sweden)

    Min-Su Park

    2016-01-01

    Full Text Available Towers and rotor-nacelles are being enlarged to respond to the need for higher gross generation of the wind turbines. However, the accompanying enlargement of the substructure supporting these larger offshore wind turbines makes it strongly influenced by the effect of wave forces. In the present study, the hybrid substructure is suggested to reduce the wave forces by composing a multicylinder having different radii near free surface and a gravity substructure at the bottom of the multicylinder. In addition, the reaction forces acting on the substructure due to the very large dead load of the offshore wind turbine require very firm foundations. This implies that the dynamic pile-soil interaction has to be fully considered. Therefore, ENSOFT Group V7.0 is used to calculate the stiffness matrices on the pile-soil interaction conditions. These matrices are then used together with the loads at TP (Transition Piece obtained from GH-Bladed for the structural analysis of the hybrid substructure by ANSYS ASAS. The structural strength and deformation are evaluated to derive an ultimate structural safety of the hybrid substructure for various soil conditions and show that the first few natural frequencies of the substructure are heavily influenced by the wind turbine. Therefore, modal analysis is carried out through GH-Bladed to examine the resonance between the wind turbine and the hybrid substructure.

  9. The Unorthodox Orbits of Substructure Halos

    CERN Document Server

    Ludlow, Aaron D; Springel, Volker; Jenkins, Adrian; Frenk, Carlos S; Helmi, Amina

    2008-01-01

    We use numerical simulations to study the properties of substructure within galaxy-sized dark matter halos. Our study extends previous work by considering the whole population of subhalos physically associated with the main system; these are subhalos that have at some time been within the virial radius of the main progenitor and have survived as self-bound entities to z=0. We find that this population extends beyond three times the virial radius and contains objects on extreme orbits. We trace the origin of these unorthodox orbits to multiple-body interactions acting during the tidal dissociation of bound groups. Multiple-body interactions affect primarily low-mass subhalos and push them onto higher energy orbits, resulting in a strong mass-dependent bias in the spatial distribution and kinematics of associated subhalos: the lower the subhalo mass at accretion time, the less concentrated and kinematically hotter their descendant population. Our findings imply that subhalos identified within the virial radius ...

  10. Factorization for substructures of boosted Higgs jets

    CERN Document Server

    Isaacson, Joshua; Li, Zhao; Yuan, C -P

    2015-01-01

    We present a perturbative QCD factorization formula for substructures of an energetic Higgs jet, taking the energy profile resulting from the $H\\to b\\bar b$ decay as an example. The formula is written as a convolution of a hard Higgs decay kernel with two $b$-quark jet functions and a soft function that links the colors of the two $b$ quarks. We derive an analytical expression to approximate the energy profile within a boosted Higgs jet, which significantly differs from those of ordinary QCD jets. This formalism also extends to boosted $W$ and $Z$ bosons in their hadronic decay modes, allowing an easy and efficient discrimination of fat jets produced from different processes.

  11. Corrosion processes and field performance of epoxy-coated reinforcing steel in marine substructures

    Energy Technology Data Exchange (ETDEWEB)

    Saguees, A.A. [Univ. of South Florida, Tampa, FL (United States). Dept. of Civil Engineering and Mechanics; Powers, R.G.; Kessler, R. [Florida Department of Transportation, Gainesville, FL (United States). Materials Office

    1994-12-31

    Severe corrosion of epoxy coated rebar in the substructure of marine bridges in the Florida Keys has prompted an investigation of the condition of other bridges in the State. Over thirty bridges were subject to field examination, which included determination of rebar condition, determination of extent of electric continuity between rebars, extraction of concrete cores, determination of chloride diffusivity, concrete resistivity measurements, and related electrochemical measurements. The results indicate that the time for development of external corrosion symptoms in the Florida Keys was dominated by the corrosion propagation stage, which in that case was comparable to that expected for plain rebar. Structures outside the Florida Keys were found to be generally corrosion-free. Extensive metal-coating disbandment was observed in virtually all structures whether or not significant chloride contamination existed at the rebar level. Chloride penetration was very slow in bridges with modem concrete formulations, suggesting that long corrosion-free service times are likely for those structures. It is expected that the corrosion-free service life in those structures will be primarily the result of concrete quality and thick cover, and not necessarily due to the use of epoxy-coated rebar.

  12. Cluster X-Ray Substructure and Radio Galaxy Correlations

    Science.gov (United States)

    Ledlow, M. J.; Burns, J. O.

    1994-12-01

    Current wisdom suggests that X-ray substructure in the intracluster medium (ICM) is fairly common in galaxy clusters. This substructure takes the form of elongations, isophotal twisting, asymmetries, and sub-clumping. Substructure is also frequently present in kinematical analysis of the galaxy velocity and spatial distributions. These features include bimodality, kurtosis or skewness, and non-Gaussian velocity distributions. Consistent with the observations, Hydro/N-Body simulations suggest that cluster-subcluster mergers may be the culprit to explain these features in the ICM gas distribution, and would indicate that many clusters, even at the present epoch, are still undergoing significant dynamical evolution. From a sample of X-ray images from the Einstein satellite and, more recently, the ROSAT mission, Burns et al. (1994) found a significant correlation between the positions of radio galaxies and subclumps within the cluster-scale X-ray emission. Burns et al. have suggested that radio galaxies reside in the residue of cluster/sub-cluster merging sites, and may therefore act as pointers to clusters with ongoing and intersting dynamical activity. We are following up these ideas with a detailed substructure analysis, and a comparison to a sample of clusters without radio galaxies. In order to determine the signficance of substructure, we have reanalyzed the X-ray images using a Bootstrap-Resampling Monte-Carlo technique. In this method, asymmetries, elongations, and other forms of substructure are evaluated using a moment-analysis similar to M{o}hr et al. (1994), with the advantage that we need not assume apriori any specific substructure-free model for the source (\\ie\\ a Beta-model). The significance of individual features is determined solely from a comparison to statistical fluctuations (including noise) of the actual data. Using this technique, we place limits on the fraction of clusters with significant substructure and test the radio galaxy/substructure

  13. Substructure System Identification for Finite Element Model Updating

    Science.gov (United States)

    Craig, Roy R., Jr.; Blades, Eric L.

    1997-01-01

    This report summarizes research conducted under a NASA grant on the topic 'Substructure System Identification for Finite Element Model Updating.' The research concerns ongoing development of the Substructure System Identification Algorithm (SSID Algorithm), a system identification algorithm that can be used to obtain mathematical models of substructures, like Space Shuttle payloads. In the present study, particular attention was given to the following topics: making the algorithm robust to noisy test data, extending the algorithm to accept experimental FRF data that covers a broad frequency bandwidth, and developing a test analytical model (TAM) for use in relating test data to reduced-order finite element models.

  14. Substructuring by Lagrange multipliers for solids and plates

    Energy Technology Data Exchange (ETDEWEB)

    Mandel, J.; Tezaur, R. [Univ. of Colorado, Denver, CO (United States); Farhat, C. [Univ. of Colorado, Boulder, CO (United States)

    1996-12-31

    We present principles and theoreretical foundation of a substructuring method for large structural problems. The algorithm is preconditioned conjugate gradients on a subspace for the dual problem. The preconditioning is proved asymptotically optimal and the method is shown to be parallel scalable, i.e., the condition number is bounded independently of the number of substructures. For plate problems, a special modification is needed that retains continuity of the displacement solution at substructure crosspoints, resulting in an asymptically optimal method. The results are confirmed by numerical experiments.

  15. Using Network Methodology to Infer Population Substructure.

    Directory of Open Access Journals (Sweden)

    Dmitry Prokopenko

    Full Text Available One of the main caveats of association studies is the possible affection by bias due to population stratification. Existing methods rely on model-based approaches like structure and ADMIXTURE or on principal component analysis like EIGENSTRAT. Here we provide a novel visualization technique and describe the problem of population substructure from a graph-theoretical point of view. We group the sequenced individuals into triads, which depict the relational structure, on the basis of a predefined pairwise similarity measure. We then merge the triads into a network and apply community detection algorithms in order to identify homogeneous subgroups or communities, which can further be incorporated as covariates into logistic regression. We apply our method to populations from different continents in the 1000 Genomes Project and evaluate the type 1 error based on the empirical p-values. The application to 1000 Genomes data suggests that the network approach provides a very fine resolution of the underlying ancestral population structure. Besides we show in simulations, that in the presence of discrete population structures, our developed approach maintains the type 1 error more precisely than existing approaches.

  16. Signatures of LCDM substructure in tidal debris

    CERN Document Server

    Siegal-Gaskins, Jennifer M

    2007-01-01

    In the past decade, surveys of the stellar component of the Galaxy such as SDSS and 2MASS have revealed a number of stellar streams. Current and future observations are rapidly increasing the precision and quantity of data available, raising the possibility of using tidal streams to constrain the distribution of dark matter in the halo. Simulations of hierarchical structure formation in LCDM cosmologies predict that the dark matter halo of a galaxy like the Milky Way contains a smooth component as well as hundreds of subhalos with masses of ~10^8 solar masses and greater, and it has been suggested that the existence of coherent tidal streams is incompatible with the expected abundance of substructure. We investigate the properties of tidal streams arising from the disruption of satellites in a variety of dark matter halo models. In general, we find that the halo shape and the specific orbital path more strongly determine the degree of disruption of the satellite than does the presence or absence of substructu...

  17. Is there substructure around M87?

    Science.gov (United States)

    Oldham, L. J.; Evans, N. W.

    2016-10-01

    We present a general method to identify infalling substructure in discrete data sets with position and line-of-sight velocity data. We exploit the fact that galaxies falling on to a brightest cluster galaxy (BCG) in a virialized cluster, or dwarf satellites falling on to a central galaxy like the Milky Way, follow nearly radial orbits. If the orbits are exactly radial, we show how to find the probability distribution for a satellite's energy, given a tracer density for the satellite population, by solving an Abel integral equation. This is an extension of Eddington's classical formula for the isotropic distribution function. When applied to a system of galaxies, clustering in energy space can then be quantified using the Kullback-Leibler divergence, and groups of objects can be identified which, though separated in the sky, may be falling in on the same orbit. This method is tested using mock data and applied to the satellite galaxy population around M87, the BCG in Virgo, and a number of associations that are found, which may represent infalling galaxy groups.

  18. Substructures formation induced by gravitational tides?

    CERN Document Server

    Renaud, F; Naab, T; Boily, C M

    2009-01-01

    Physics lectures always refer to the tides as a disruptive effect. However, tides can also be compressive. When the potential of two galaxies overlap, as happens during a merger, fully compressive tides can develop and have a strong impact on the dynamics of substructures such as star clusters or tidal dwarf galaxies. Using N-body simulations of a large set of mergers, we noticed the importance of these tidal modes at cluster scale. With a model of the Antennae galaxies, we conclude that the positions and timescales of these tidal modes match the actual distribution of young clusters. A detailed study of the statistics of the compressive tides shows a stunning correlation between this purely gravitational effect and the observed properties of the star clusters. In this contribution, we introduce the concept of compressive tide and show its relevance in the special case of the Antennae galaxies. We extend our conclusions to a broad range of parameters and discuss their implications on several critical points s...

  19. A new interface element for connecting independently modeled substructures

    Science.gov (United States)

    Ransom, Jonathan B.; Mccleary, Susan L.; Aminpour, Mohammad A.

    1993-01-01

    A new interface element based on the hybrid variational formulation is presented and demonstrated. The element provides a means of connecting independently modeled substructures whose nodes along the common boundary need not be coincident. The interface element extends previous work to include connecting an arbitrary number of substructures, the use of closed and generally curved interfaces, and the use of multiple, possibly nested, interfaces. Several applications of the element are presented and aspects of the implementation are discussed.

  20. THE SEGUE K GIANT SURVEY. III. QUANTIFYING GALACTIC HALO SUBSTRUCTURE

    Energy Technology Data Exchange (ETDEWEB)

    Janesh, William; Morrison, Heather L.; Ma, Zhibo; Harding, Paul [Department of Astronomy, Case Western Reserve University, Cleveland, OH 44106 (United States); Rockosi, Constance [UCO/Lick Observatory, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States); Starkenburg, Else [Department of Physics and Astronomy, University of Victoria, P.O. Box 1700, STN CSC, Victoria BC V8W 3P6 (Canada); Xue, Xiang Xiang; Rix, Hans-Walter [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Beers, Timothy C. [Department of Physics and JINA Center for the Evolution of the Elements, University of Notre Dame, Notre Dame, IN 46556 (United States); Johnson, Jennifer [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Lee, Young Sun [Department of Astronomy and Space Science, Chungnam National University, Daejeon 34134 (Korea, Republic of); Schneider, Donald P. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States)

    2016-01-10

    We statistically quantify the amount of substructure in the Milky Way stellar halo using a sample of 4568 halo K giant stars at Galactocentric distances ranging over 5–125 kpc. These stars have been selected photometrically and confirmed spectroscopically as K giants from the Sloan Digital Sky Survey’s Sloan Extension for Galactic Understanding and Exploration project. Using a position–velocity clustering estimator (the 4distance) and a model of a smooth stellar halo, we quantify the amount of substructure in the halo, divided by distance and metallicity. Overall, we find that the halo as a whole is highly structured. We also confirm earlier work using blue horizontal branch (BHB) stars which showed that there is an increasing amount of substructure with increasing Galactocentric radius, and additionally find that the amount of substructure in the halo increases with increasing metallicity. Comparing to resampled BHB stars, we find that K giants and BHBs have similar amounts of substructure over equivalent ranges of Galactocentric radius. Using a friends-of-friends algorithm to identify members of individual groups, we find that a large fraction (∼33%) of grouped stars are associated with Sgr, and identify stars belonging to other halo star streams: the Orphan Stream, the Cetus Polar Stream, and others, including previously unknown substructures. A large fraction of sample K giants (more than 50%) are not grouped into any substructure. We find also that the Sgr stream strongly dominates groups in the outer halo for all except the most metal-poor stars, and suggest that this is the source of the increase of substructure with Galactocentric radius and metallicity.

  1. Myocardial Bridging

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2016-02-01

    Full Text Available Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

  2. Quantifying the Significance of Substructure in Coronal Loops

    Science.gov (United States)

    McKeough, K. B. D.; Kashyap, V.; McKillop, S.

    2014-12-01

    A method to infer the presence of small-scale substructure in SDO/AIA (Atmospheric Imaging Assembly on the Solar Dynamics Observatory) images of coronal loops is developed. We can classify visible loop structure based on this propensity to show substructure which puts constraints on contemporary solutions to the coronal heating problem. The method uses the Bayesian algorithm Low-count Image Reconstruction and Analysis (LIRA) to infer the multi-scale component of the loops which describes deviations from a smooth model. The increase in contrast of features in this multi-scale component is determined using a statistic that estimates the sharpness across the image. Regions with significant substructure are determined using p-value upper bounds. We are able to locate substructure visible in Hi-C (High-Resolution Coronal Imager) data that are not salient features in the corresponding AIA image. Looking at coronal loops at different regions of the Sun (e.g., low-lying structure and loops in the upper corona) we are able to map where detectable substructure exists and thus the influence of the nanoflare heating process. We acknowledge support from AIA under contract SP02H1701R from Lockheed-Martin to SAO.

  3. The SEGUE K Giant Survey. III. Quantifying Galactic Halo Substructure

    CERN Document Server

    Janesh, William; Ma, Zhibo; Harding, Paul; Rockosi, Constance; Starkenburg, Else; Xue, Xiang Xiang; Rix, Hans-Walter; Beers, Timothy C; Johnson, Jennifer; Lee, Young Sun; Schneider, Donald P

    2015-01-01

    We statistically quantify the amount of substructure in the Milky Way stellar halo using a sample of 4568 halo K giant stars at Galactocentric distances ranging over 5-125 kpc. These stars have been selected photometrically and confirmed spectroscopically as K giants from the Sloan Digital Sky Survey's SEGUE project. We use a position-velocity clustering estimator (the 4distance) and a smooth stellar halo model to quantify the amount of substructure in the halo. Overall, we find that the halo as a whole is highly structured, and confirm earlier work using BHB stars which showed that there is an increasing amount of substructure with increasing Galactocentric radius. In addition, we find that the amount of substructure in the halo increases with increasing metallicity, and that the K giant sample shows significantly stronger substructure than the BHB stars, which only sample the most metal poor stars. Using a friends-of-friends algorithm to identify groups, we find that a large fraction ($\\sim 33\\%$) of the st...

  4. Functional group and substructure searching as a tool in metabolomics.

    Directory of Open Access Journals (Sweden)

    Masaaki Kotera

    Full Text Available BACKGROUND: A direct link between the names and structures of compounds and the functional groups contained within them is important, not only because biochemists frequently rely on literature that uses a free-text format to describe functional groups, but also because metabolic models depend upon the connections between enzymes and substrates being known and appropriately stored in databases. METHODOLOGY: We have developed a database named "Biochemical Substructure Search Catalogue" (BiSSCat, which contains 489 functional groups, >200,000 compounds and >1,000,000 different computationally constructed substructures, to allow identification of chemical compounds of biological interest. CONCLUSIONS: This database and its associated web-based search program (http://bisscat.org/ can be used to find compounds containing selected combinations of substructures and functional groups. It can be used to determine possible additional substrates for known enzymes and for putative enzymes found in genome projects. Its applications to enzyme inhibitor design are also discussed.

  5. Floating substructure flexibility of large-volume 10MW offshore wind turbine platforms in dynamic calculations

    DEFF Research Database (Denmark)

    Borg, Michael; Hansen, Anders Melchior; Bredmose, Henrik

    2016-01-01

    Designing floating substructures for the next generation of 10MW and larger wind turbines has introduced new challenges in capturing relevant physical effects in dynamic simulation tools. In achieving technically and economically optimal floating substructures, structural flexibility may increase...

  6. Bridge Management Systems

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper bridge management systems are discussed with special emphasis on management systems for reinforced concrete bridges. Management systems for prestressed concrete bridges, steel bridges, or composite bridges can be developed in a similar way....

  7. Substructure in the Stellar Halos of the Aquarius Simulations

    NARCIS (Netherlands)

    Helmi, Amina; Cooper, A. P.; White, S. D. M.; Cole, S.; Frenk, C. S.; Navarro, J. F.

    2011-01-01

    We characterize the substructure in the simulated stellar halos of Cooper et al. which were formed by the disruption of satellite galaxies within the cosmological N-body simulations of galactic halos of the Aquarius project. These stellar halos exhibit a wealth of tidal features: broad overdensities

  8. Small scale substructure, collapse time and dynamical friction

    CERN Document Server

    Gambera, M

    1996-01-01

    We solve numerically the equations of motion for the collapse of a shell of baryonic matter, made of galaxies and substructure of $ 10^{6} M_{\\odot} \\div 10^{9} M_{\\odot}$, taking into account the dynamical friction and the parameters on which it depends: the peaks' height $\

  9. Evolutionarily conserved substrate substructures for automated annotation of enzyme superfamilies.

    Directory of Open Access Journals (Sweden)

    Ranyee A Chiang

    Full Text Available The evolution of enzymes affects how well a species can adapt to new environmental conditions. During enzyme evolution, certain aspects of molecular function are conserved while other aspects can vary. Aspects of function that are more difficult to change or that need to be reused in multiple contexts are often conserved, while those that vary may indicate functions that are more easily changed or that are no longer required. In analogy to the study of conservation patterns in enzyme sequences and structures, we have examined the patterns of conservation and variation in enzyme function by analyzing graph isomorphisms among enzyme substrates of a large number of enzyme superfamilies. This systematic analysis of substrate substructures establishes the conservation patterns that typify individual superfamilies. Specifically, we determined the chemical substructures that are conserved among all known substrates of a superfamily and the substructures that are reacting in these substrates and then examined the relationship between the two. Across the 42 superfamilies that were analyzed, substantial variation was found in how much of the conserved substructure is reacting, suggesting that superfamilies may not be easily grouped into discrete and separable categories. Instead, our results suggest that many superfamilies may need to be treated individually for analyses of evolution, function prediction, and guiding enzyme engineering strategies. Annotating superfamilies with these conserved and reacting substructure patterns provides information that is orthogonal to information provided by studies of conservation in superfamily sequences and structures, thereby improving the precision with which we can predict the functions of enzymes of unknown function and direct studies in enzyme engineering. Because the method is automated, it is suitable for large-scale characterization and comparison of fundamental functional capabilities of both characterized

  10. National Bridge Inventory (NBI) Bridges

    Data.gov (United States)

    Department of Homeland Security — The NBI is a collection of information (database) describing the more than 600,000 of the Nation's bridges located on public roads, including Interstate Highways,...

  11. Floating substructure flexibility of large-volume 10MW offshore wind turbine platforms in dynamic calculations

    Science.gov (United States)

    Borg, Michael; Melchior Hansen, Anders; Bredmose, Henrik

    2016-09-01

    Designing floating substructures for the next generation of 10MW and larger wind turbines has introduced new challenges in capturing relevant physical effects in dynamic simulation tools. In achieving technically and economically optimal floating substructures, structural flexibility may increase to the extent that it becomes relevant to include in addition to the standard rigid body substructure modes which are typically described through linear radiation-diffraction theory. This paper describes a method for the inclusion of substructural flexibility in aero-hydro-servo-elastic dynamic simulations for large-volume substructures, including wave-structure interactions, to form the basis of deriving sectional loads and stresses within the substructure. The method is applied to a case study to illustrate the implementation and relevance. It is found that the flexible mode is significantly excited in an extreme event, indicating an increase in predicted substructure internal loads.

  12. Towards an Understanding of the Correlations in Jet Substructure

    CERN Document Server

    Adams, D; Asquith, L.; Backovic, M.; Barillari, T.; Berta, P.; Bertolini, D.; Buckley, A.; Butterworth, J.; Camacho Toro, R.C.; Caudron, J.; Chien, Y.T.; Cogan, J.; Cooper, B.; Curtin, D.; Debenedetti, C.; Dolen, J.; Eklund, M.; El Hedri, S.; Ellis, S.D.; Embry, T.; Ferencek, D.; Ferrando, J.; Fleischmann, S.; Freytsis, M.; Giulini, M.; Han, Z.; Hare, D.; Harris, P.; Hinzmann, A.; Hoing, R.; Hornig, A.; Jankowiak, M.; Johns, K.; Kasieczka, G.; Kogler, R.; Lampl, W.; Larkoski, A.J.; Lee, C.; Leone, R.; Loch, P.; Lopez Mateos, D.; Lou, H.K.; Low, M.; Maksimovic, P.; Marchesini, I.; Marzani, S.; Masetti, L.; McCarthy, R.; Menke, S.; Miller, D.W.; Mishra, K.; Nachman, B.; Nef, P.; O'Grady, F.T.; Ovcharova, A.; Picazio, A.; Pollard, C.; Potter-Landua, B.; Potter, C.; Rappoccio, S.; Rojo, J.; Rutherfoord, J.; Salam, G.P.; Schabinger, R.M.; Schwartzman, A.; Schwartz, M.D.; Shuve, B.; Sinervo, P.; Soper, D.; Sosa Corral, D.E.; Spannowsky, M.; Strauss, E.; Swiatlowski, M.; Thaler, J.; Thomas, C.; Thompson, E.; Tran, N.V.; Tseng, J.; Usai, E.; Valery, L.; Veatch, J.; Vos, M.; Waalewijn, W.; Wacker, J.; Young, C.

    2015-01-01

    Over the past decade, a large number of jet substructure observables have been proposed in the literature, and explored at the LHC experiments. Such observables attempt to utilize the internal structure of jets in order to distinguish those initiated by quarks, gluons, or by boosted heavy objects, such as top quarks and W bosons. This report, originating from and motivated by the BOOST2013 workshop, presents original particle-level studies that aim to improve our understanding of the relationships between jet substructure observables, their complementarity, and their dependence on the underlying jet properties, particularly the jet radius and jet transverse momentum. This is explored in the context of quark/gluon discrimination, boosted W boson tagging and boosted top quark tagging.

  13. A Unified Approach to Substructuring and Structural Modification Problems

    Directory of Open Access Journals (Sweden)

    Walter D’Ambrogio

    2004-01-01

    Full Text Available Substructures coupling is still an important tool in several applications of modal analysis, especially structural modification and structures assembling. The subject is particularly relevant in virtual prototyping of complex systems and responds to actual industrial needs. This paper analyzes the possibility of assembling together different substructures' models. The important role of rotational DoFs is highlighted, underlying the difficulty of assembling theoretical and experimental models, for which, usually, the rotational DoFs are not available. Expansion techniques can be used to provide this information as well as appropriate modelling of joints. With this information FRF models, modal models and FE models can be appropriately combined together and solutions for several cases of practical interest are presented. The analyzed procedures are tested on purpose-built benchmarks, showing limits and capabilities of each of them.

  14. Towards an understanding of the correlations in jet substructure

    Energy Technology Data Exchange (ETDEWEB)

    Adams, D. [Brookhaven National Laboratory, Upton, NY (United States); Arce, A. [Duke University, Durham, NC (United States); Asquith, L. [University of Sussex, Brighton (United Kingdom); Backovic, M. [CP3, Universite catholique du Louvain, Louvain-la-Neuve (Belgium); Barillari, T.; Menke, S. [Max-Planck-Institute fuer Physik, Munich (Germany); Berta, P. [Charles University in Prague, FMP, Prague (Czech Republic); Bertolini, D. [University of California, Berkeley, CA (United States); Buckley, A.; Ferrando, J.; Pollard, C. [University of Glasgow, G12 8QQ (United Kingdom); Butterworth, J.; Cooper, B. [University College London, WC1E 6BT (United Kingdom); Camacho Toro, R.C.; Picazio, A. [University of Geneva, Geneva 4 (Switzerland); Caudron, J.; El Hedri, S.; Masetti, L. [Universitaet Mainz (Germany); Chien, Y.T.; Hornig, A.; Lee, C. [Los Alamos National Laboratory, Los Alamos, NM (United States); Cogan, J.; Nachman, B.; Nef, P.; Schwartzman, A.; Strauss, E.; Swiatlowski, M. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Curtin, D. [University of Maryland, College Park, MD (United States); Debenedetti, C. [University of California, Santa Cruz, CA (United States); Dolen, J.; Rappoccio, S. [University at Buffalo, Buffalo, NY (United States); Eklund, M.; Embry, T.; Johns, K.; Lampl, W.; Leone, R.; Loch, P.; O' Grady, F.T.; Rutherfoord, J.; Veatch, J. [University of Arizona, Tucson, AZ (United States); Ellis, S.D. [University of Washington, Seattle, WA (United States); Ferencek, D. [Rutgers University, Piscataway, NJ (United States); Fleischmann, S. [Bergische Universitaet Wuppertal, Wuppertal (Germany); Freytsis, M.; Lopez Mateos, D.; Schwartz, M.D. [Harvard University, Cambridge, MA (United States); Giulini, M.; Sosa Corral, D.E. [Universitaet Heidelberg, Heidelberg (Germany); Han, Z.; Soper, D. [University of Oregon, Eugene, OR (United States); Hare, D.; Mishra, K.; Tran, N.V. [Fermi National Accelerator Laboratory, Batavia, IL (United States); Harris, P.; Potter-Landua, B.; Potter, C.; Thomas, C.; Young, C. [CERN, Geneva 23 (Switzerland); Hinzmann, A. [Universitaet Zuerich, Zurich (Switzerland); Hoing, R.; Kogler, R.; Marchesini, I.; Usai, E. [Universitaet Hamburg, Hamburg (Germany); Jankowiak, M. [New York University, New York, NY (United States); Kasieczka, G. [ETH Zuerich, Zurich (Switzerland); Larkoski, A.J.; Marzani, S.; Thaler, J. [Massachusetts Institute of Technology, Cambridge, MA (United States); Lou, H.K. [Princeton University, Princeton, NJ (United States); Low, M.; Miller, D.W. [University of Chicago, Zurich, IL (United States); Maksimovic, P. [Johns Hopkins University, Baltimore, MD (United States); McCarthy, R. [YITP, Stony Brook University, Stony Brook, NY (United States); Ovcharova, A. [University of California, Berkeley National Laboratory, Berkeley, CA (United States); Rojo, J.; Tseng, J. [University of Oxford, Oxford (United Kingdom); Salam, G.P. [CERN, Geneva 23 (Switzerland); LPTHE, UPMC Univ. Paris 6 and CNRS UMR, Paris (France); Schabinger, R.M. [Universidad Autonoma de Madrid, Madrid (Spain); Shuve, B. [Perimeter Institute for Theoretical Physics, ON (Canada); Sinervo, P. [University of Toronto, Toronto, ON (Canada); Spannowsky, M. [University of Durham, IPPP, Durham (United Kingdom); Thompson, E. [Columbia University, New York, NY (United States); Valery, L. [LPC Clermont-Ferrand, Aubiere Cedex (France); Vos, M. [Instituto de Fisica Corpuscular, IFIC/CSIC-UVEG, Valencia (Spain); Waalewijn, W. [University of Amsterdam, Amsterdam (Netherlands); Wacker, J. [Stanford Institute for Theoretical Physics, Stanford, CA (United States)

    2015-09-15

    Over the past decade, a large number of jet substructure observables have been proposed in the literature, and explored at the LHC experiments. Such observables attempt to utilize the internal structure of jets in order to distinguish those initiated by quarks, gluons, or by boosted heavy objects, such as top quarks and W bosons. This report, originating from and motivated by the BOOST2013 workshop, presents original particle-level studies that aim to improve our understanding of the relationships between jet substructure observables, their complementarity, and their dependence on the underlying jet properties, particularly the jet radius and jet transverse momentum. This is explored in the context of quark/gluon discrimination, boosted W boson tagging and boosted top quark tagging. (orig.)

  15. Searches for Exotic Physics in ATLAS using substructure techniques

    CERN Document Server

    Behr, Janna Katharina; The ATLAS collaboration

    2016-01-01

    The significant increase of the centre-of-mass energy of the Large Hadron Collider (LHC) from 8 to 13 TeV has allowed the experiments at the LHC to explore previously inaccessible kinematic regimes in their search for phenomena beyond the Standard Model of Particle Physics. The sensitivity of these searches depends crucially on the efficient reconstruction and identification of hadronic decays of highly energetic (boosted) objects, the decay products of which are typically collimated into a single large jet with a characteristic substructure. In this contribution, I review the searches conducted by the ATLAS experiment on data recorded during 2015 and 2016 that rely on substructure techniques to identify signatures of interest. A particular emphasis is placed on recent developments in the rapidly evolving field of boosted object tagging.

  16. Particle Reconstruction at the LHC using Jet Substructure Algorithms

    CERN Document Server

    Rathjens, Denis

    2012-01-01

    The LHC-era with √ s = 7 TeV allows for a new energy-regime to be accessed. Heavy mass-resonances up to 3.5 TeV/c 2 are in reach. If such heavy particles decay hadronically to much lighter Standard Model particles such as top, Z or W, the jets of the decay products have a sizeable probability to be merged into a single jet. The result is a boosted jet with substructure. This diploma thesis deals with the phenomena of boosted jets, algorithms to distinguish substructure in these jets from normal hadronization and methods to further improve searches with boosted jets. The impact of such methods is demonstrated in an example analysis of a Z’→ tt¯-scenario on 2 fb −1 of data.

  17. Tracing the Cosmic Web substructure with Lagrangian submanifold

    CERN Document Server

    Shandarin, Sergei F

    2014-01-01

    A new computational paradigm for the analysis of substructure of the Cosmic Web in cosmological cold dark matter simulations is proposed. We introduce a new data-field --- the flip-flop field ---which carries wealth of information about the history and dynamics of the structure formation in the universe. The flip-flop field is an ordered data set in Lagrangian space representing the number of turns inside out sign reversals of an elementary volume of each collisionless fluid element represented by a computational particle in a N-body simulation. This field is computed using the Lagrangian submanifold, i.e. the three-dimensional dark matter sheet in the six-dimensional space formed by three Lagrangian and three Eulerian coordinates of the simulation particles. It is demonstrated that the very rich substructure of dark matter haloes and the void regions can be reliably and unambiguously recovered from the flip-flop field.

  18. Searches for Exotic Physics in ATLAS using Substructure Techniques

    CERN Document Server

    Behr, Janna Katharina; The ATLAS collaboration

    2017-01-01

    The significant increase of the centre-of-mass energy of the Large Hadron Collider (LHC) from 8 to 13 TeV has allowed the LHC experiments to explore previously inaccessible kinematic regimes in their search for phenomena beyond the Standard Model. The sensitivity of these searches depends crucially on the efficient reconstruction and identification of hadronic decays of highly energetic (boosted) objects, the decay products of which are typically collimated into a single large jet with a characteristic substructure. In this contribution, the searches conducted by the ATLAS experiment on data recorded during 2015 and 2016 that rely on jet substructure techniques to identify signatures of interest are reviewed. A particular emphasis is placed on recent developments in the rapidly evolving field of boosted object tagging.

  19. Stick-slip substructure in rapid tape peeling

    KAUST Repository

    Thoroddsen, Sigurdur T.

    2010-10-15

    The peeling of adhesive tape is known to proceed with a stick-slip mechanism and produces a characteristic ripping sound. The peeling also produces light and when peeled in a vacuum, even X-rays have been observed, whose emissions are correlated with the slip events. Here we present direct imaging of the detachment zone when Scotch tape is peeled off at high speed from a solid surface, revealing a highly regular substructure, during the slip phase. The typical 4-mm-long slip region has a regular substructure of transverse 220 μm wide slip bands, which fracture sideways at speeds over 300 m/s. The fracture tip emits waves into the detached section of the tape at ∼100 m/s, which promotes the sound, so characteristic of this phenomenon.

  20. Constraining the Milky Way potential using the dynamical kinematic substructures

    Directory of Open Access Journals (Sweden)

    Antoja T.

    2012-02-01

    Full Text Available We present a method to constrain the potential of the non-axisymmetric components of the Galaxy using the kinematics of stars in the solar neighborhood. The basic premise is that dynamical substructures in phase-space (i.e. due to the bar and/or spiral arms are associated with families of periodic or irregular orbits, which may be easily identified in orbital frequency space. We use the “observed” positions and velocities of stars as initial conditions for orbital integrations in a variety of gravitational potentials. We then compute their characteristic frequencies, and study the structure present in the frequency maps. We find that the distribution of dynamical substructures in velocity- and frequency-space is best preserved when the integrations are performed in the “true” gravitational potential.

  1. Abell 2744: Too much substructure for Lambda CDM?

    CERN Document Server

    Schwinn, J; Baugh, C M; Bartelmann, M; Eckert, D; Harvey, D; Natarajan, P; Massey, R

    2016-01-01

    The massive substructures found in Abell 2744 by Jauzac et al. (2016) present a challenge to the cold dark matter paradigm due to their number and proximity to the cluster centre. We use one of the biggest N-body simulations, the Millennium XXL, to investigate the substructure in a large sample of massive dark matter haloes. A range of effects which influence the comparison with the observations is considered, extending the preliminary evaluation carried out by Jauzac et al. (2016). There are many tens of haloes in the simulation with a total mass comparable with or larger than that of Abell 2744. However, we find no haloes with a number and distribution of massive substructures (> 5 10^13 Msun) that is close to that inferred from the observations of Abell 2744. The application of extreme value statistics suggests that we would need a simulation of at least ten times the volume of the Millennium XXL to find a single dark matter halo with a similar internal structure to Abell 2744. Explaining the distribution ...

  2. Trans-Dimensional Bayesian Inference for Gravitational Lens Substructures

    CERN Document Server

    Brewer, Brendon J; Lewis, Geraint F

    2015-01-01

    We introduce a Bayesian solution to the problem of inferring the density profile of strong gravitational lenses when the lens galaxy may contain multiple dark or faint substructures. The source and lens models are based on a superposition of an unknown number of non-negative basis functions (or "blobs") whose form was chosen with speed as a primary criterion. The prior distribution for the blobs' properties is specified hierarchically, so the mass function of substructures is a natural output of the method. We use reversible jump Markov Chain Monte Carlo (MCMC) within Diffusive Nested Sampling (DNS) to sample the posterior distribution and evaluate the marginal likelihood of the model, including the summation over the unknown number of blobs in the source and the lens. We demonstrate the method on a simulated data set with a single substructure, which is recovered well with moderate uncertainties. We also apply the method to the g-band image of the "Cosmic Horseshoe" system, and find some hints of potential s...

  3. Bridged graphite oxide materials

    Science.gov (United States)

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

    2010-01-01

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

  4. Building Bridges

    DEFF Research Database (Denmark)

    The report Building Bridges adresses the questions why, how and for whom academic audience research has public value, from the different points of view of the four working groups in the COST Action IS0906 Transforming Audiences, Transforming Societies – “New Media Genres, Media Literacy and Trust...... in the Media”, “Audience Interactivity and Participation”, “The Role of Media and ICT Use for Evolving Social Relationships” and “Audience Transformations and Social Integration”. Building Bridges is the result of an ongoing dialogue between the Action and non-academic stakeholders in the field of audience...... Belgrade), Leo Pekkala (Finnish Centre for Media Education and Audiovisual Media/MEKU), Julie Uldam (Network on Civic Engagement and Social Innovation) and Gabriella Velics (Community Media Forum Europe)....

  5. Mathematical bridges

    CERN Document Server

    Andreescu, Titu; Tetiva, Marian

    2017-01-01

    Building bridges between classical results and contemporary nonstandard problems, Mathematical Bridges embraces important topics in analysis and algebra from a problem-solving perspective. Blending old and new techniques, tactics and strategies used in solving challenging mathematical problems, readers will discover numerous genuine mathematical gems throughout that will heighten their appreciation of the inherent beauty of mathematics. Most of the problems are original to the authors and are intertwined in a well-motivated exposition driven by representative examples. The book is structured to assist the reader in formulating and proving conjectures, as well as devising solutions to important mathematical problems by making connections between various concepts and ideas from different areas of mathematics. Instructors and educators teaching problem-solving courses or organizing mathematics clubs, as well as motivated mathematics students from high school juniors to college seniors, will find Mathematical Bri...

  6. Plastic Bridge

    Institute of Scientific and Technical Information of China (English)

    履之

    1994-01-01

    Already ubiquitous in homes and cars, plastic is now appearing inbridges. An academic-industrial consortium based at the University ofCalifornia in San Diego is launching a three-year research program aimed atdeveloping the world’s first plastic highway bridge, a 450-foot span madeentirely from glass-,carbon,and polymer-fiber-reinforced composite mate-rials, the stuff of military aircraft. It will cross Interstate 5 to connect thetwo sides of the school’s campus.

  7. Experimental Study of Properties of Pervious Concrete used for Bridge Superstructure

    DEFF Research Database (Denmark)

    Lund, Mia Schou Møller; Hansen, Kurt Kielsgaard; Hertz, Kristian Dahl

    2014-01-01

    -Chain Bridges are a new patented bridge technology consisting of a number of Super-Light Deck elements, which are post-tensioned to create an arch bridge used for example for highways. The present study investigates how pervious concrete can be applied as a stabilizing filling materi-al between the arch...... substructure and the wearing course. One pervious concrete mixture contain-ing air entrainment is designed and tested. The tests include investigations of compaction meth-ods, compressive strength, stiffness, frost resistance and permeability....

  8. GLAST And Dark Matter Substructure in the Milky Way

    Energy Technology Data Exchange (ETDEWEB)

    Kuhlen, Michael; /Princeton, Inst. Advanced Study; Diemand, Jurg; /UC, Santa Cruz, Astron. Astrophys.; Madau, Piero; /UC, Santa Cruz, Astron. Astrophys. /Garching, Max Planck Inst.

    2011-11-29

    We discuss the possibility of GLAST detecting gamma-rays from the annihilation of neutralino dark matter in the Galactic halo. We have used 'Via Lactea', currently the highest resolution simulation of cold dark matter substructure, to quantify the contribution of subhalos to the annihilation signal. We present a simulated allsky map of the expected gamma-ray counts from dark matter annihilation, assuming standard values of particle mass and cross section. In this case GLAST should be able to detect the Galactic center and several individual subhalos. One of the most exciting discoveries that the Gamma-ray Large Area Space Telescope (GLAST) could make, is the detection of gamma-rays from the annihilation of dark matter (DM). Such a measurement would directly address one of the major physics problems of our time: the nature of the DM particle. Whether or not GLAST will actually detect a DM annihilation signal depends on both unknown particle physics and unknown astrophysics theory. Particle physics uncertainties include the type of particle (axion, neutralino, Kaluza-Klein particle, etc.), its mass, and its interaction cross section. From the astrophysical side it appears that DM is not smoothly distributed throughout the Galaxy halo, but instead exhibits abundant clumpy substructure, in the form of thousands of so-called subhalos. The observability of DM annihilation radiation originating in Galactic DM subhalos depends on their abundance, distribution, and internal properties. Numerical simulations have been used in the past to estimate the annihilation flux from DM substructure, but since the subhalo properties, especially their central density profile, which determines their annihilation luminosity, are very sensitive to numerical resolution, it makes sense to re-examine their contribution with higher resolution simulations.

  9. Fatigue reassessment for lifetime extension of offshore wind monopile substructures

    Science.gov (United States)

    Ziegler, Lisa; Muskulus, Michael

    2016-09-01

    Fatigue reassessment is required to decide about lifetime extension of aging offshore wind farms. This paper presents a methodology to identify important parameters to monitor during the operational phase of offshore wind turbines. An elementary effects method is applied to analyze the global sensitivity of residual fatigue lifetimes to environmental, structural and operational parameters. Therefore, renewed lifetime simulations are performed for a case study which consists of a 5 MW turbine with monopile substructure in 20 m water depth. Results show that corrosion, turbine availability, and turbulence intensity are the most influential parameters. This can vary strongly for other settings (water depth, turbine size, etc.) making case-specific assessments necessary.

  10. Unexpected relationships of substructured populations in Chinese Locusta migratoria

    Directory of Open Access Journals (Sweden)

    Ji Ya-Jie

    2009-06-01

    Full Text Available Abstract Background Highly migratory species are usually expected to have minimal population substructure because strong gene flow has the effect of homogenizing genetic variation over geographical populations, counteracting random drift, selection and mutation. The migratory locust Locusta migratoria belongs to a monotypic genus, and is an infamous pest insect with exceptional migratory ability – with dispersal documented over a thousand kilometers. Its distributional area is greater than that of any other locust or grasshopper, occurring in practically all the temperate and tropical regions of the eastern hemisphere. Consequently, minimal population substructuring is expected. However, in marked contrast to its high dispersal ability, three geographical subspecies have been distinguished in China, with more than nine being biologically and morphologically identified in the world. Such subspecies status has been under considerable debate. Results By multilocus microsatellite genotyping analysis, we provide ample genetic evidence for strong population substructure in this highly migratory insect that conforms to geography. More importantly, our genetic data identified an unexpected cryptic subdivision and demonstrated a strong affiliation of the East China locusts to those in Northwest/Northern China. The migratory locusts in China formed three distinct groups, viz. (1 the Tibetan group, comprising locusts from Tibet and nearby West China high mountain regions; this is congruent with the previously recognized Tibetan subspecies, L. m. tibetensis; (2 the South China group, containing locusts from the Hainan islands; this corresponds to the Southeast Asia oriental tropical subspecies L. m. manilensis; (3 the North China group, including locusts from the Northwest and Northern China (the Asiatic subspecies L. m. migratoria, Central China and Eastern China regions. Therefore, the traditional concept on Locusta subspecies status established from

  11. Validation of metabolic pathway databases based on chemical substructure search.

    Science.gov (United States)

    Félix, Liliana; Valiente, Gabriel

    2007-09-01

    Metabolic pathway databases such as KEGG contain information on thousands of biochemical reactions drawn from the biomedical literature. Ensuring consistency of such large metabolic pathways is essential to their proper use. In this paper, we present a new method to determine consistency of an important class of biochemical reactions. Our method exploits the knowledge of the atomic rearrangement pattern in biochemical reactions, to reduce the automatic atom mapping problem to a series of chemical substructure searches between the substrate and the product of a biochemical reaction. As an illustrative application, we describe the exhaustive validation of a substantial portion from the latest release of the KEGG LIGAND database.

  12. Expected damages of retrofitted bridges with RC jacketing

    Science.gov (United States)

    Montes, O.; Jara, J. M.; Jara, M.; Olmos, B. A.

    2015-07-01

    The bridge infrastructure in many countries of the world consists of medium span length structures built several decades ago and designed for very low seismic forces. Many of them are reinforced concrete structures that according to the current code regulations have to be rehabilitated to increase their seismic capacity. One way to reduce the vulnerability of the bridges is by using retrofitting techniques that increase the strength of the structure or by incorporating devices to reduce the seismic demand. One of the most common retrofit techniques of the bridges substructures is the use of RC jacketing; this research assesses the expected damages of seismically deficient medium length highway bridges retrofitted with reinforced concrete jacketing, by conducting a parametric study. We select a suite of twenty accelerograms of subduction earthquakes recorded close to the Pacific Coast in Mexico. The original structures consist of five 30 m span simple supported bridges with five pier heights of 5 m, 10 m, 15 m 20 and 25 m and the analyses include three different jacket thickness and three steel ratios. The bridges were subjected to the seismic records and non-linear time history analyses were carried out by using the OpenSEEs Plataform. Results allow selecting the reinforced concrete jacketing that better improves the expected seismic behavior of the bridge models.

  13. Cold Dark Matter Substructures in Early-Type Galaxy Halos

    CERN Document Server

    Fiacconi, Davide; Potter, Doug; Stadel, Joachim

    2016-01-01

    We present initial results from the "Ponos" zoom-in numerical simulations of dark matter substructures in massive ellipticals. Two very highly resolved dark matter halos with $M_{\\rm vir}=1.2\\times 10^{13}$ $M_{\\odot}$ and $M_{\\rm vir}=6.5\\times 10^{12}$ $M_{\\odot}$ and different ("violent" vs. "quiescent") assembly histories have been simulated down to $z=0$ in a $\\Lambda$CDM cosmology with a total of 921,651,914 and 408,377,544 particles, respectively. Within the virial radius, the total mass fraction in self-bound $M_{\\rm sub}>10^6$ $M_{\\odot}$ subhalos at the present epoch is 15% for the violent host and 16.5% for the quiescent one. At $z=0.7$, these fractions increase to 19 and 33%, respectively, as more recently accreted satellites are less prone to tidal destruction. In projection, the average fraction of surface mass density in substructure at a distance of $R/R_{\\rm vir}=0.02$ ($\\sim 5-10$ kpc) from the two halo centers ranges from 0.6% to $\\gtrsim 2$%, significantly higher than measured in simulatio...

  14. Residuated lattices an algebraic glimpse at substructural logics

    CERN Document Server

    Galatos, Nikolaos; Kowalski, Tomasz; Ono, Hiroakira

    2007-01-01

    The book is meant to serve two purposes. The first and more obvious one is to present state of the art results in algebraic research into residuated structures related to substructural logics. The second, less obvious but equally important, is to provide a reasonably gentle introduction to algebraic logic. At the beginning, the second objective is predominant. Thus, in the first few chapters the reader will find a primer of universal algebra for logicians, a crash course in nonclassical logics for algebraists, an introduction to residuated structures, an outline of Gentzen-style calculi as well as some titbits of proof theory - the celebrated Hauptsatz, or cut elimination theorem, among them. These lead naturally to a discussion of interconnections between logic and algebra, where we try to demonstrate how they form two sides of the same coin. We envisage that the initial chapters could be used as a textbook for a graduate course, perhaps entitled Algebra and Substructural Logics. As the book progresses the f...

  15. Replaceable Substructures for Efficient Part-Based Modeling

    KAUST Repository

    Liu, Han

    2015-05-01

    A popular mode of shape synthesis involves mixing and matching parts from different objects to form a coherent whole. The key challenge is to efficiently synthesize shape variations that are plausible, both locally and globally. A major obstacle is to assemble the objects with local consistency, i.e., all the connections between parts are valid with no dangling open connections. The combinatorial complexity of this problem limits existing methods in geometric and/or topological variations of the synthesized models. In this work, we introduce replaceable substructures as arrangements of parts that can be interchanged while ensuring boundary consistency. The consistency information is extracted from part labels and connections in the original source models. We present a polynomial time algorithm that discovers such substructures by working on a dual of the original shape graph that encodes inter-part connectivity. We demonstrate the algorithm on a range of test examples producing plausible shape variations, both from a geometric and from a topological viewpoint. © 2015 The Author(s) Computer Graphics Forum © 2015 The Eurographics Association and John Wiley & Sons Ltd. Published by John Wiley & Sons Ltd.

  16. Detection of a Dark Substructure through Gravitational Imaging

    CERN Document Server

    Vegetti, S; Bolton, A; Treu, T; Gavazzi, R

    2009-01-01

    We report the detection of a dark substructure through direct gravitational imaging - undetected in the HST-WFPC2 F606W image - in the gravitational lens galaxy of SLACS SDSSJ0946+1006 (the "Double Einstein Ring"). The detection is based on a Bayesian grid reconstruction of the two-dimensional surface density of the galaxy inside an annulus around its Einstein radius (few kpc). The detection of a small mass concentration in the surface density maps has a strong statistical significance. We confirm this detection by modeling the system including a parametric mass model with a tidally truncated pseudo-Jaffe density profile; in that case the substructure mass is M_sub=(3.51+-0.15)x10^9 Msun, located at (-0.651+-0.038,1.040+-0.034)'', precisely where also the surface density map shows a strong convergence peak (Bayes factor dlog(E)=-128.0; equivalent to a ~16-sigma detection). The result is robust under substantial changes in the model and the data-set (e.g. PSF, pixel number and scale, source and potential regul...

  17. Design and Analysis of Jacket Substructures for Offshore Wind Turbines

    Directory of Open Access Journals (Sweden)

    I-Wen Chen

    2016-04-01

    Full Text Available This study focused on investigating various existing types of offshore jacket substructures along with a proposed twisted-tripod jacket type (modified jacket (MJ-structures. The architectures of the three-leg structure, as well as the patented twisted jacket structure motivated the design of the proposed MJ-structures. The dimensions of the structures were designed iteratively using static stress analysis to ensure that all structures had a similar level of load-carrying capability. The numerical global buckling analyses were performed for all structures after the validation by the scaled-down experiments. The local buckling strength of all compressive members was analyzed using the NORSOK standard. The results showed that the proposed MJ-structures possess excellent structural behavior and few structural nodes and components competitive with the patented twisted jacket structures, while still maintaining the advantages of low material usage similar to the three-leg jacket structures. This study provides alternatives for the initial selection and design of offshore wind turbine substructures for green energy applications.

  18. Fossil Group Origins VII. Galaxy substructures in fossil systems

    CERN Document Server

    Zarattini, S; Aguerri, J A L; Boschin, W; Barrena, R; del Burgo, C; Castro-Rodriguez, N; Corsini, E M; D'Onghia, E; Kundert, A; Méndez-Abreu, J; Sánchez-Janssen, R

    2016-01-01

    Fossil groups are expected to be the final product of galaxy merging within galaxy groups. In simulations, they are predicted to assemble their mass at high redshift. This early formation allows for the innermost $M^\\ast$ galaxies to merge into a massive central galaxy. Then, they are expected to maintain their fossil status because of the few interactions with the large-scale structure. In this context, the magnitude gap between the two brightest galaxies of the system is considered a good indicator of its dynamical status. As a consequence, the systems with the largest gaps should be dynamically relaxed. In order to examine the dynamical status of these systems, we systematically analyze, for the first time, the presence of galaxy substructures in a sample of 12 spectroscopically-confirmed fossil systems with redshift $z \\le 0.25$. We apply a number of tests in order to investigate the substructure in fossil systems in the two-dimensional space of projected positions out to $R_{200}$. Moreover, for a subsam...

  19. 3 long bridges of dream were realized Opening of West Seto Motorway; Yume no 3 kakyo ga jitsugen/nishiseto jidoshado haitsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-06-10

    Onomichi-Imabari route/Setouchi Simanami Thruway, which adorned the finish of Honshu-Shikoku projects was completed on 1st, May. With this completion, 3 long bridges of dream were completely realized, following to Kojima-Sakaide (1988) and Kobe-Naruto (1998). This time, 5 bridges of this Motorway, the world's longest cable stayed bridge Tatara Long Bridge, world's first 3 continuous suspension bridge Kurushima Strait No.1{approx}No.3 bridge and New Onomichi Long Bridge, were opened. 10 bridges including 5 bridges (In-noshima Long Bridge, Ikeguchi Bridge, Omishima Bridge, Hakata/Oshima Long Bridge and Oshima Long Bridge) already under service connect 9 islands between Onomichi, Hiroshima Prefecture and Imabari, Ehime Prefecture, with a route 59 km long. Characteristic design was adopted for each bridge to demonstrate world's highest bridge erection technology of Japan. In a series of concrete construction to support superstructure of these bridges, underwater non-segregation type concrete with low hydration heat cement mainly for foundation and substructure, and high fluidity concrete for dense reinforcement layout were adopted. (translated by NEDO)

  20. Formation of deformation substructures in FCC crystals under the influence of point defect fluxes

    OpenAIRE

    Matveev, M. V.; Selivanikova, Olga Valerievna; Cherepanov, Dmitry Nikolaevich

    2016-01-01

    The article deals with sub-structural transformations in FCC crystals under the influence of point defect fluxes. Different relationships between accumulation of point defects in crystal and substructure transformations, in particular during the process of fragmented dislocation structure formation have been received.

  1. Inspection of Asian Lacquer Substructures by Terahertz Time-Domain Imaging (THz-TDI)

    DEFF Research Database (Denmark)

    Dandolo, Corinna Ludovica Koch; Fukunaga, Kaori; Kohzuma, Yoshei;

    2016-01-01

    Lacquering is considered one of the most representative Asian artistic techniques. While the decorative part of lacquerwares is the lacquer itself, their substructures serve as the backbone of the object itself. Very little is known about these hidden substructures. Since lacquerwares are mostly ...

  2. A Comparison of Reduced Order Modeling Techniques Used in Dynamic Substructuring [PowerPoint

    Energy Technology Data Exchange (ETDEWEB)

    Roettgen, Dan [Wisc; Seeger, Benjamin [Stuttgart; Tai, Wei Che [Washington; Baek, Seunghun [Michigan; Dossogne, Tilan [Liege; Allen, Matthew S [Wisc; Kuether, Robert J.; Brake, Matthew Robert; Mayes, Randall L.

    2016-01-01

    Experimental dynamic substructuring is a means whereby a mathematical model for a substructure can be obtained experimentally and then coupled to a model for the rest of the assembly to predict the response. Recently, various methods have been proposed that use a transmission simulator to overcome sensitivity to measurement errors and to exercise the interface between the substructures; including the Craig-Bampton, Dual Craig-Bampton, and Craig-Mayes methods. This work compares the advantages and disadvantages of these reduced order modeling strategies for two dynamic substructuring problems. The methods are first used on an analytical beam model to validate the methodologies. Then they are used to obtain an experimental model for structure consisting of a cylinder with several components inside connected to the outside case by foam with uncertain properties. This represents an exceedingly difficult structure to model and so experimental substructuring could be an attractive way to obtain a model of the system.

  3. A Comparison of Reduced Order Modeling Techniques Used in Dynamic Substructuring.

    Energy Technology Data Exchange (ETDEWEB)

    Roettgen, Dan; Seegar, Ben; Tai, Wei Che; Baek, Seunghun; Dossogne, Tilan; Allen, Matthew; Kuether, Robert J.; Brake, Matthew Robert; Mayes, Randall L.

    2015-10-01

    Experimental dynamic substructuring is a means whereby a mathematical model for a substructure can be obtained experimentally and then coupled to a model for the rest of the assembly to predict the response. Recently, various methods have been proposed that use a transmission simulator to overcome sensitivity to measurement errors and to exercise the interface between the substructures; including the Craig-Bampton, Dual Craig-Bampton, and Craig-Mayes methods. This work compares the advantages and disadvantages of these reduced order modeling strategies for two dynamic substructuring problems. The methods are first used on an analytical beam model to validate the methodologies. Then they are used to obtain an experimental model for structure consisting of a cylinder with several components inside connected to the outside case by foam with uncertain properties. This represents an exceedingly difficult structure to model and so experimental substructuring could be an attractive way to obtain a model of the system.

  4. Resonance Related Spiral Substructure in a Galactic Gaseous Disk

    CERN Document Server

    Yáñez, Miguel A; Martos, Marco A; Hayes, John C

    2007-01-01

    We use high resolution 2D hydrodynamic simulations to study the formation of spiral substructure in the gaseous disk of a galaxy. The obtained gaseous response is driven by a self-consistent non-axisymmetric potential obtained from an imposed spiral mass distribution. We highlight the importance of ultraharmonic resonances in generating these features. The temporal evolution of the system is followed with the parallel ZEUS-MP code, and we follow the steepening of perturbations induced by the spiral potential until large-scale shocks emerge. These shocks exhibit bifurcations that protrude from the gaseous arms and continue to steepen until new shocks are formed. When the contribution from the spiral potential relative to the axisymmetric background is increased from our default value, spurs protrude from the main arms after several revolutions of the gaseous disk. Such spurs overlap on top of the aforementioned shocks. These results support the hypothesis that a complicated gaseous response can coexist with an...

  5. Decorrelated Jet Substructure Tagging using Adversarial Neural Networks

    CERN Document Server

    CERN. Geneva

    2017-01-01

    We describe a strategy for constructing a neural network jet substructure tagger which powerfully discriminates boosted decay signals while remaining largely uncorrelated with the jet mass. This reduces the impact of systematic uncertainties in background modeling while enhancing signal purity, resulting in improved discovery significance relative to existing taggers. The network is trained using an adversarial strategy, resulting in a tagger that learns to balance classification accuracy with decorrelation. As a benchmark scenario, we consider the case where large-radius jets originating from a boosted Z' decay are discriminated from a background of nonresonant quark and gluon jets. We show that in the presence of systematic uncertainties on the background rate, our adversarially-trained, decorrelated tagger considerably outperforms a conventionally trained neural network, despite having a slightly worse signal-background separation power. We generalize the adversarial training technique to include a paramet...

  6. Substructure effects on the collapse of density perturbations

    CERN Document Server

    Popolo, A D

    1996-01-01

    We solve numerically the equations of motion for the collapse of a shell of baryonic matter, made of galaxies and substructure of $ 10^{6} M_{\\odot}- 10^{9} M_{\\odot}$, falling into the central regions of a cluster of galaxies taking account of dynamical friction. We calculate the evolution of the expansion parameter, a(t), of the perturbation using a coefficient of dynamical friction, $ \\eta_{0}$, calculated for a perturbation in which clustering is absent and a coefficient $ \\eta_{cl}$ obtained from a clustered one. The effect of the dynamical friction is to slow down the collapse (V. Antonuccio-Delogu \\& S. Colafrancesco 1994, hereafter AC) producing an observable variation of the parameter of expansion of the shell. The effect increases with increasing $ time depends on $ \\eta_{0}$ and $ \\eta_{cl}$. keywords: {cosmology: theory- galaxies: formation}

  7. Performance of boosted object and jet substructure techniques

    CERN Document Server

    Schramm, Steven; The ATLAS collaboration

    2016-01-01

    Hadronic decays of heavy particles with momenta much larger than their mass result in their decay products being reconstructable as a single large ­radius jet. The study of the substructure of these jets allows the separation of these boosted decays with respect to more common jets from light­ quarks and gluons. Several techniques have been developed by the phenomenology and experimental community to identify jets coming from hadronic decays of boosted top quarks, W, Z and Higgs bosons. The performance of several such techniques have been studied in ATLAS using fully­ simulated Monte Carlo events, and validated on data using pure samples of top quarks, W bosons from top decays and dijet events. Results of these studies will be presented for Run 1 as well as Run 2 of the LHC.

  8. Substructure drag effects and recrystallization textures in aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Higginson, R. [Univ. of Sheffield (United Kingdom). Dept. of Engineering Materials; Bate, P. [Doncasters plc, Melbourne (United Kingdom)

    1999-03-10

    Many important recrystallization texture components in metals such as aluminium originate from nuclei in which the mobile high-angle boundary exists prior to, or is formed in the early stages of, annealing. Nucleation can then occur by a process known as strain-induced boundary migration (SIBM). It is possible that this process will involve several growing subgrains, and the drag from that substructure can then have a significant effect. A simple model is used to demonstrate how changes in the overall driving force for recrystallization and Zener drag can affect recrystallization textures when SIBM is involved. This is discussed in relation to experimental observations and the evidence for this process is reviewed.

  9. Dynamics of 10 clusters of galaxies with substructures

    Energy Technology Data Exchange (ETDEWEB)

    Lakhchaura, Kiran; Singh, K. P., E-mail: kiran_astro@tifr.res.in [Department of Astronomy and Astrophysics, Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400 005 (India)

    2014-06-01

    We present a detailed Chandra study of a sample of 10 clusters of galaxies selected based on the presence of substructures in their optical images. The X-ray surface brightness maps of most of these clusters show anisotropic morphologies, especially in the central regions. A total of 22 well resolved significantly bright X-ray peaks (corresponding with high-density regions) are seen in the central parts (within r{sub c} /2) of the clusters. Multiple peaks are seen in central parts of six clusters. We found 11 peaks to have optical counterparts (10 coinciding with the brightest cluster galaxies of the 10 clusters and 1 coinciding with the second brightest galaxy in A539). For most of the clusters, the optical substructures detected in the previous studies are found to be outside the field of view of Chandra. In the spectroscopically produced two-dimensional temperature maps, significantly lower temperatures are seen at the locations of three peaks (two in A539 and one in A376). The centers of five clusters in our sample also host regions of higher temperature compared to the ambient medium, indicating the presence of galaxy scale mergers. The X-ray luminosity, gas mass, and central cooling time estimates for all the clusters are presented. The radial X-ray surface-brightness profiles of all but one of the clusters are found to be best-fitted with a double-β model, pointing toward the presence of double-phased central gas due to cool cores. The cooling time estimates of all the clusters, however, indicate that none of them hosts a strong cool core, although the possibility of weak cool cores cannot be ruled out.

  10. Probing deformation substructure by synchrotron X-ray diffraction and dislocation dynamics modelling.

    Science.gov (United States)

    Korsunsky, Alexander M; Hofmann, Felix; Song, Xu; Eve, Sophie; Collins, Steve P

    2010-09-01

    Materials characterization at the nano-scale is motivated by the desire to resolve the structural aspects and deformation behavior at length scales relevant to those mechanisms that define the novel and unusual properties of nano-structured materials. A range of novel techniques has recently become accessible with the help of synchrotron X-ray beams that can be focused down to spot sizes of less than a few microns on the sample. The unique combination of tunability (energy selection), parallelism and brightness of synchrotron X-ray beams allows their use for high resolution diffraction (determination of crystal structure and transformations, analysis of dislocation sub-structures, orientation and texture analysis, strain mapping); small angle X-ray scattering (analysis of nano-scale voids and defects; orientation analysis) and imaging (radiography and tomography). After a brief review of the state-of-the-art capabilities for monochromatic and white beam synchrotron diffraction, we consider the usefulness of these techniques for the task of bridging the gap between experiment and modeling. Namely, we discuss how the experiments can be configured to provide information relevant to the validation and improvement of modeling approaches, and also how the results of various simulations can be post-processed to improve the possibility of (more or less) direct comparison with experiments. Using the example of some recent experiments carried out on beamline 116 at Diamond Light Source near Oxford, we discuss how such experimental results can be interpreted in view and in conjunction with numerical deformation models, particularly those incorporating dislocation effects, e.g., finite-element based pseudo-continuum strain gradient formulations, and discrete dislocation simulations. Post-processing of FE and discrete dislocation simulations is described, illustrating the kind of information that can be extracted from comparisons between modeling and experimental data.

  11. Cable Supported Bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    Cable supported bridges in the form of suspension bridges and cable-stayed bridges are distinguished by their ability to overcome large spans.The book concentrates on the synthesis of cable supported bridges, covering both design and construction aspects. The analytical part covers simple methods...

  12. Nonlinear signal-based control with an error feedback action for nonlinear substructuring control

    Science.gov (United States)

    Enokida, Ryuta; Kajiwara, Koichi

    2017-01-01

    A nonlinear signal-based control (NSBC) method utilises the 'nonlinear signal' that is obtained from the outputs of a controlled system and its linear model under the same input signal. Although this method has been examined in numerical simulations of nonlinear systems, its application in physical experiments has not been studied. In this paper, we study an application of NSBC in physical experiments and incorporate an error feedback action into the method to minimise the error and enhance the feasibility in practice. Focusing on NSBC in substructure testing methods, we propose nonlinear substructuring control (NLSC), that is a more general form of linear substructuring control (LSC) developed for dynamical substructured systems. In this study, we experimentally and numerically verified the proposed NLSC via substructuring tests on a rubber bearing used in base-isolated structures. In the examinations, NLSC succeeded in gaining accurate results despite significant nonlinear hysteresis and unknown parameters in the substructures. The nonlinear signal feedback action in NLSC was found to be notably effective in minimising the error caused by nonlinearity or unknown properties in the controlled system. In addition, the error feedback action in NLSC was found to be essential for maintaining stability. A stability analysis based on the Nyquist criterion, which is used particularly for linear systems, was also found to be efficient for predicting the instability conditions of substructuring tests with NLSC and useful for the error feedback controller design.

  13. Jet Substructure at the Tevatron and LHC: New results, new tools, new benchmarks

    CERN Document Server

    Altheimer, A; Asquith, L; Brooijmans, G; Butterworth, J; Campanelli, M; Chapleau, B; Cholakian, A E; Chou, J P; Dasgupta, M; Davison, A; Dolen, J; Ellis, S D; Essig, R; Fan, J J; Field, R; Fregoso, A; Gallicchio, J; Gershtein, Y; Gomes, A; Haas, A; Halkiadakis, E; Halyo, V; Hoeche, S; Hook, A; Hornig, A; Huang, P; Izaguirre, E; Jankowiak, M; Kribs, G; Krohn, D; Larkoski, A J; Lath, A; Lee, C; Lee, S J; Loch, P; Maksimovic, P; Martinez, M; Miller, D W; Plehn, T; Prokofiev, K; Rahmat, R; Rappoccio, S; Safonov, A; Salam, G P; Schumann, S; Schwartz, M D; Schwartzman, A; Seymour, M; Shao, J; Sinervo, P; Son, M; Soper, D E; Spannowsky, M; Stewart, I W; Strassler, M; Strauss, E; Takeuchi, M; Thaler, J; Thomas, S; Tweedie, B; Vasquez Sierra, R; Vermilion, C K; Villaplana, M; Vos, M; Wacker, J; Walker, D; Walsh, J R; Wang, L-T; Wilbur, S; Yavin, I; Zhu, W

    2012-01-01

    In this report we review recent theoretical progress and the latest experimental results in jet substructure from the Tevatron and the LHC. We review the status of and outlook for calculation and simulation tools for studying jet substructure. Following up on the report of the Boost 2010 workshop, we present a new set of benchmark comparisons of substructure techniques, focusing on the set of variables and grooming methods that are collectively known as "top taggers". To facilitate further exploration, we have attempted to collect, harmonise, and publish software implementations of these techniques.

  14. Exploring Milkyway Halo Substructures with Large-Area Sky Surveys

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ting [Texas A & M Univ., College Station, TX (United States)

    2016-01-01

    Over the last two decades, our understanding of the Milky Way has been improved thanks to large data sets arising from large-area digital sky surveys. The stellar halo is now known to be inhabited by a variety of spatial and kinematic stellar substructures, including stellar streams and stellar clouds, all of which are predicted by hierarchical Lambda Cold Dark Matter models of galaxy formation. In this dissertation, we first present the analysis of spectroscopic observations of individual stars from the two candidate structures discovered using an M-giant catalog from the Two Micron All-Sky Survey. The follow-up observations show that one of the candidates is a genuine structure which might be associated with the Galactic Anticenter Stellar Structure, while the other one is a false detection due to the systematic photometric errors in the survey or dust extinction in low Galactic latitudes. We then presented the discovery of an excess of main sequence turn-off stars in the direction of the constellations of Eridanus and Phoenix from the first-year data of the Dark Energy Survey (DES) – a five-year, 5,000 deg2 optical imaging survey in the Southern Hemisphere. The Eridanus-Phoenix (EriPhe) overdensity is centered around l ~ 285° and b ~ -60° and the Poisson significance of the detection is at least 9σ. The EriPhe overdensity has a cloud-like morphology and the extent is at least ~ 4 kpc by ~ 3 kpc in projection, with a heliocentric distance of about d ~ 16 kpc. The EriPhe overdensity is morphologically similar to the previously-discovered Virgo overdensity and Hercules-Aquila cloud. These three overdensities lie along a polar plane separated by ~ 120° and may share a common origin. In addition to the scientific discoveries, we also present the work to improve the photometric calibration in DES using auxiliary calibration systems, since the photometric errors can cause false detection in first the halo substructure. We present a detailed description of the two

  15. Bridges in Complex Networks

    CERN Document Server

    Wu, Ang-Kun; Liu, Yang-Yu

    2016-01-01

    A bridge in a graph is an edge whose removal disconnects the graph and increases the number of connected components. We calculate the fraction of bridges in a wide range of real-world networks and their randomized counterparts. We find that real networks typically have more bridges than their completely randomized counterparts, but very similar fraction of bridges as their degree-preserving randomizations. We define a new edge centrality measure, called bridgeness, to differentiate the importance of a bridge in damaging a network. We find that certain real networks have very large average and variance of bridgeness compared to their degree-preserving randomizations and other real networks. Finally, we offer an analytical framework to calculate the bridge fraction and average bridgeness for uncorrelated random networks with arbitrary degree distributions.

  16. Inspection of Asian Lacquer Substructures by Terahertz Time-Domain Imaging (THz-TDI)

    Science.gov (United States)

    Dandolo, Corinna Ludovica Koch; Fukunaga, Kaori; Kohzuma, Yoshei; Kiriyama, Kyoko; Matsuda, Kazutaka; Jepsen, Peter Uhd

    2017-04-01

    Lacquering is considered one of the most representative Asian artistic techniques. While the decorative part of lacquerwares is the lacquer itself, their substructures serve as the backbone of the object itself. Very little is known about these hidden substructures. Since lacquerwares are mostly composed of organic materials, such as urushi, wood, carbon black, and fabrics which are very X-ray transparent, standard X-ray radiography has some problems in achieving clear X-ray radiographic images. Therefore, we wanted to contribute to the understanding of the lacquer manufacturing technique by inspecting the substructures of Asian lacquerwares by means of THz time-domain imaging (THz-TDI). Three different kinds of Asian lacquerwares were examined by THz-TDI, and the outcomes have been compared with those obtained by standard X-radiography. THz-TDI provides unique information on lacquerwares substructures, aiding in the comprehension of the manufacturing technology yielding to these precious artefacts.

  17. Pseudoscalar searches with dileptonic tops and jet substructure

    Science.gov (United States)

    Gonçalves, Dorival; López-Val, David

    2016-11-01

    The quest for new heavy states is a critical component of the LHC physics program. In this paper, we study the search for pseudoscalar bosons produced in association with a t t ¯ pair. We consider the final state t t ¯A →t t ¯b b ¯ with a dileptonic top-pair signature, and reconstruct the boosted A →b b ¯ candidate with jet substructure techniques, achieving a remarkable sensitivity over a broad range of pseudoscalar masses and Yukawa couplings. We apply this strategy to a type-I two-Higgs-doublet model (2HDM), demonstrating its ability to probe a realistic, UV-complete extended Higgs sector. In particular, we find that the 13 TeV LHC with 300 fb-1 of data can constrain the region tan β >1.5 at 95% C.L. for a light pseudoscalar with mA=50 GeV . Moreover, the whole mass range 20 GeV

  18. Shaken and Stirred: The Milky Way's Dark Substructures

    CERN Document Server

    Sawala, Till; Johansson, Peter H; Frenk, Carlos S; Navarro, Julio F; Oman, Kyle A; White, Simon D M

    2016-01-01

    The predicted abundance and properties of the low-mass substructures embedded inside larger dark matter haloes differ sharply among alternative dark matter models. Too small to host galaxies themselves, these subhaloes may still be detected via gravitational lensing, or via perturbations of the Milky Way's globular cluster streams and its stellar disk. Here we use the Apostle cosmological simulations to predict the abundance and the spatial and velocity distributions of subhaloes in the range 10^6.5-10^8.5 solar masses inside haloes of mass ~ 10^12 solar masses in LCDM. Although these subhaloes are themselves devoid of baryons, we find that baryonic effects are important. Compared to corresponding dark matter only simulations, the loss of baryons from subhaloes and stronger tidal disruption due to the presence of baryons near the centre of the main halo, reduce the number of subhaloes by ~ 1/4 to 1/2, independently of subhalo mass, but increasingly towards the host halo centre. We also find that subhaloes hav...

  19. Probing the substructure of $f_0(1370)$

    CERN Document Server

    Fariborz, Amir H; Asrar, Abdorreza

    2015-01-01

    Within an effective nonlinear chiral Lagrangian framework the substructure of $f_0(1370)$ is studied. The investigation is conducted in the context of a global picture of scalar mesons in which the importance of the underlying connections among scalar mesons below and above 1 GeV is recognized and implemented. These connections are due to the mixings among various quark-antiquarks, four-quarks and glue components and play a central role in understanding the properties of scalar mesons. Iterative Monte Carlo simulations are first performed on the 14-dimensional parameter space of the model and sets of points in this parameter space (the global sets) that give an overall agreement with all experimental data on mass spectrum, various decay widths and decay ratios of all isosinglet scalar states below 2 GeV are determined. Then within each global set, subsets that give closest agreement for the properties of $f_0(1370)$ are studied. Unlike the properties of other isosinglet states that show a range of variation w...

  20. Jet substructure using semi-inclusive jet functions within SCET

    CERN Document Server

    Kang, Zhong-Bo; Vitev, Ivan

    2016-01-01

    We propose a new method to evaluate jet substructure observables in inclusive jet measurements based upon semi-inclusive jet functions within the framework of Soft Collinear Effective Theory (SCET). In this work we consider the jet fragmentation function, where a hadron $h$ is identified inside a fully reconstructed jet as a first example. We introduce a new semi-inclusive fragmenting jet function ${\\mathcal G}^h_i(z= \\omega_J/\\omega,z_h=\\omega_h/\\omega_J,\\omega_J, R,\\mu)$ which depends on the jet radius $R$ and the large light-cone momenta of the parton '$i$' initiating the jet ($\\omega$), the jet ($\\omega_J$), and the hadron $h$ ($\\omega_h$). We are then able to express the jet fragmentation function as a semi-inclusive jet observable rather than as an exclusive one, which is closer to the actual experimental measurements. We demonstrate the consistency of the effective field theory treatment and standard perturbative QCD calculations at next-to-leading order (NLO). We further derive the renormalization gro...

  1. Virtual sensing of structural vibrations using dynamic substructuring

    Science.gov (United States)

    Kullaa, Jyrki

    2016-10-01

    Virtual sensing techniques use information available from a limited set of physical sensors together with the finite element model to calculate an estimate of the quantity of interest. In structural dynamics applications, analytical mode shapes from the finite element model are typically used as a basis to estimate the response at unmeasured locations by an expansion algorithm. An alternative is to model only the interesting part of the structure using substructuring techniques, in which the natural modes are replaced by component modes consisting of a selected number of fixed interface modes plus the interface constraint modes. They are mutually independent and compose a valid subspace for estimating the unmeasured response. If the number of interface degrees of freedom is large, interface reduction is applied. The main advantage of the proposed approach is that the modelling effort can be substantially decreased, because only part of the structure is modelled and the modelling uncertainties, non-linearities, or changes in the omitted structure can be ignored. The method is validated by numerical simulations of three different structures under unknown excitation. Different types and locations of virtual sensors are studied. Also, the effects of noise and model errors are investigated. The most accurate estimation is obtained if the virtual sensor is located away from the interface and close to a physical sensor.

  2. Jet substructure and probes of CP violation in Vh production

    CERN Document Server

    Godbole, Rohini M; Mohan, Kirtimaan A; White, Christopher D

    2014-01-01

    We analyse the hVV (V = W, Z) vertex in a model independent way using Vh production. To that end , we consider possible corrections to the Standard Model Higgs Lagrangian, in the form of higher dimensional operators which parametrise the effects of new physics. In our analysis, we pay special attention to linear observables that can be used to probe CP violation in the same. By considering the associated production of a Higgs boson with a vector boson (W or Z), we use jet substructure methods to define angular observables which are sensitive to new physics effects, including an asymmetry which is linearly sensitive to the presence of CP odd effects. We demonstrate how to use these observables to place bounds on the presence of higher dimensional operators, and quantify these statements using a log likelihood analysis. Our approach allows one to probe separately the hZZ and hWW vertices, involving arbitrary combinations of BSM operators, at the Large Hadron Collider.

  3. Substructural influence in the hot rolling of Al alloys

    Science.gov (United States)

    McQueen, H. J.

    1998-06-01

    The industrial rolling of aluminum alloys is generally conducted in multistage schedules of 10-15 passes partly on reversing mills and partly on continuous mills with temperature declining from 500°C to between 300°C and 250°C. Static recrystallization may take place in long intervals after passes with higher temperature and strain. During lower temperature intervals, only static recovery takes place so that in the following passes the flow curves exhibit higher initial stresses. Dynamic recovery decreases gradually through the hot-, warm-, and cold-working ranges but is reduced as the concentration of solutes and particles increase. Recrystallization is much more sensitive to temperature and alloying and is retarded by increased dynamic recovery. The texture of sheet depends on lattice-dependent Taylor rotations during dislocation slip, enhanced recovery of certain deformation band orientations, and preferred nucleation and growth during interpass pauses or annealing. Schedule optimization can be guided by physical simulation or modeling based on recrystallization kinetics to attain selected strengthening substructure, recrystallized grain size, and texture for product earing control.

  4. A NEW METHOD TO QUANTIFY X-RAY SUBSTRUCTURES IN CLUSTERS OF GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Andrade-Santos, Felipe; Lima Neto, Gastao B.; Lagana, Tatiana F. [Departamento de Astronomia, Instituto de Astronomia, Geofisica e Ciencias Atmosfericas, Universidade de Sao Paulo, Geofisica e Ciencias Atmosfericas, Rua do Matao 1226, Cidade Universitaria, 05508-090 Sao Paulo, SP (Brazil)

    2012-02-20

    We present a new method to quantify substructures in clusters of galaxies, based on the analysis of the intensity of structures. This analysis is done in a residual image that is the result of the subtraction of a surface brightness model, obtained by fitting a two-dimensional analytical model ({beta}-model or Sersic profile) with elliptical symmetry, from the X-ray image. Our method is applied to 34 clusters observed by the Chandra Space Telescope that are in the redshift range z in [0.02, 0.2] and have a signal-to-noise ratio (S/N) greater than 100. We present the calibration of the method and the relations between the substructure level with physical quantities, such as the mass, X-ray luminosity, temperature, and cluster redshift. We use our method to separate the clusters in two sub-samples of high- and low-substructure levels. We conclude, using Monte Carlo simulations, that the method recuperates very well the true amount of substructure for small angular core radii clusters (with respect to the whole image size) and good S/N observations. We find no evidence of correlation between the substructure level and physical properties of the clusters such as gas temperature, X-ray luminosity, and redshift; however, analysis suggest a trend between the substructure level and cluster mass. The scaling relations for the two sub-samples (high- and low-substructure level clusters) are different (they present an offset, i.e., given a fixed mass or temperature, low-substructure clusters tend to be more X-ray luminous), which is an important result for cosmological tests using the mass-luminosity relation to obtain the cluster mass function, since they rely on the assumption that clusters do not present different scaling relations according to their dynamical state.

  5. Contribution to Structural Elucidation: Behaviours of Substructures Partially Defined from 2D NMR

    Institute of Scientific and Technical Information of China (English)

    EPOUHE, Celine; FAN, Bo-Tao; YUAN, Shen-Gang; PANAYE, A.; DOUCET, J. P

    2003-01-01

    Structural elucidation (automatic determination of the structure of a molecule from its spectra) is frequently hampered by combinatorial explosion when trying to assemble the identified substructures. We devised a new method which can avoid this pitfall by a systematic examination of allowed 13C chemical shifts ranges for all substructures chemically possible and combined with a progressive pruning thanks to neighbouring relationships appearing from 2D NMR. This method is explained by a detailed example.

  6. Substructure in the Most Massive GEEC Groups: Field-like Populations in Dynamically Active Groups

    CERN Document Server

    Hou, Annie; Wilman, David J; McGee, Sean L; Harris, William E; Connelly, Jennifer L; Balogh, Michael L; Mulchaey, John S; Bower, Richard G

    2012-01-01

    The presence of substructure in galaxy groups and clusters is believed to be a sign of recent galaxy accretion and can be used not only to probe the assembly history of these structures, but also the evolution of their member galaxies. Using the Dressler-Shectman (DS) Test, we study substructure in a sample of intermediate redshift (z ~ 0.4) galaxy groups from the Group Environment and Evolution Collaboration (GEEC) group catalog. We find that 4 of the 15 rich GEEC groups, with an average velocity dispersion of ~525 km s-1, are identified as having significant substructure. The identified regions of localized substructure lie on the group outskirts and in some cases appear to be infalling. In a comparison of galaxy properties for the members of groups with and without substructure, we find that the groups with substructure have a significantly higher fraction of blue and star-forming galaxies and a parent colour distribution that resembles that of the field population rather than the overall group population....

  7. Analysis and application of European genetic substructure using 300 K SNP information.

    Directory of Open Access Journals (Sweden)

    Chao Tian

    2008-01-01

    Full Text Available European population genetic substructure was examined in a diverse set of >1,000 individuals of European descent, each genotyped with >300 K SNPs. Both STRUCTURE and principal component analyses (PCA showed the largest division/principal component (PC differentiated northern from southern European ancestry. A second PC further separated Italian, Spanish, and Greek individuals from those of Ashkenazi Jewish ancestry as well as distinguishing among northern European populations. In separate analyses of northern European participants other substructure relationships were discerned showing a west to east gradient. Application of this substructure information was critical in examining a real dataset in whole genome association (WGA analyses for rheumatoid arthritis in European Americans to reduce false positive signals. In addition, two sets of European substructure ancestry informative markers (ESAIMs were identified that provide substantial substructure information. The results provide further insight into European population genetic substructure and show that this information can be used for improving error rates in association testing of candidate genes and in replication studies of WGA scans.

  8. Systematic benchmark of substructure search in molecular graphs - From Ullmann to VF2

    Directory of Open Access Journals (Sweden)

    Ehrlich Hans-Christian

    2012-07-01

    Full Text Available Abstract Background Searching for substructures in molecules belongs to the most elementary tasks in cheminformatics and is nowadays part of virtually every cheminformatics software. The underlying algorithms, used over several decades, are designed for the application to general graphs. Applied on molecular graphs, little effort has been spend on characterizing their performance. Therefore, it is not clear how current substructure search algorithms behave on such special graphs. One of the main reasons why such an evaluation was not performed in the past was the absence of appropriate data sets. Results In this paper, we present a systematic evaluation of Ullmann’s and the VF2 subgraph isomorphism algorithms on molecular data. The benchmark set consists of a collection of 1235 SMARTS substructure expressions and selected molecules from the ZINC database. The benchmark evaluates substructures search times for complete database scans as well as individual substructure-molecule pairs. In detail, we focus on the influence of substructure formulation and size, the impact of molecule size, and the ability of both algorithms to be used on multiple cores. Conclusions The results show a clear superiority of the VF2 algorithm in all test scenarios. In general, both algorithms solve most instances in less than one millisecond, which we consider to be acceptable. Still, in direct comparison, the VF2 is most often several folds faster than Ullmann’s algorithm. Additionally, Ullmann’s algorithm shows a surprising number of run time outliers.

  9. Nuclear substructure reorganization during late stageerythropoiesis is selective and does not involve caspase cleavage ofmajor nuclear substructural proteins

    Energy Technology Data Exchange (ETDEWEB)

    Krauss, Sharon Wald; Lo, Annie J.; Short, Sarah A.; Koury, MarkJ.; Mohandas, Narla; Chasis, Joel Anne

    2005-04-06

    Enucleation, a rare feature of mammalian differentiation, occurs in three cell types: erythroblasts, lens epithelium and keratinocytes. Previous investigations suggest that caspase activation functions in lens epithelial and keratinocyte enucleation, as well as in early erythropoiesis encompassing BFU-E differentiation to proerythroblast. To determine whether caspase activation contributes to later erythropoiesis and whether nuclear substructures other than chromatin reorganize, we analyzed distributions of nuclear subcompartment proteins and assayed for caspase-induced cleavage of subcompartmental target proteins in mouse erythroblasts. We found that patterns of lamin B in the filamentous network interacting with both the nuclear envelope and DNA, nuclear matrix protein NuMA, and splicing factors Sm and SC35 persisted during nuclear condensation, consistent with effective transcription of genes expressed late in differentiation. Thus nuclear reorganization prior to enucleation is selective, allowing maintenance of critical transcriptional processes independent of extensive chromosomal reorganization. Consistent with these data, we found no evidence for caspase-induced cleavage of major nuclear subcompartment proteins during late erythropoiesis, in contrast to what has been observed in early erythropoiesis and in lens epithelial and keratinocyte differentiation. These findings imply that nuclear condensation and extrusion during terminal erythroid differentiation involve novel mechanisms that do not entail major activation of apoptotic machinery.

  10. Analysis of substructural variation in families of enzymatic proteins with applications to protein function prediction

    Directory of Open Access Journals (Sweden)

    Fofanov Viacheslav Y

    2010-05-01

    Full Text Available Abstract Background Structural variations caused by a wide range of physico-chemical and biological sources directly influence the function of a protein. For enzymatic proteins, the structure and chemistry of the catalytic binding site residues can be loosely defined as a substructure of the protein. Comparative analysis of drug-receptor substructures across and within species has been used for lead evaluation. Substructure-level similarity between the binding sites of functionally similar proteins has also been used to identify instances of convergent evolution among proteins. In functionally homologous protein families, shared chemistry and geometry at catalytic sites provide a common, local point of comparison among proteins that may differ significantly at the sequence, fold, or domain topology levels. Results This paper describes two key results that can be used separately or in combination for protein function analysis. The Family-wise Analysis of SubStructural Templates (FASST method uses all-against-all substructure comparison to determine Substructural Clusters (SCs. SCs characterize the binding site substructural variation within a protein family. In this paper we focus on examples of automatically determined SCs that can be linked to phylogenetic distance between family members, segregation by conformation, and organization by homology among convergent protein lineages. The Motif Ensemble Statistical Hypothesis (MESH framework constructs a representative motif for each protein cluster among the SCs determined by FASST to build motif ensembles that are shown through a series of function prediction experiments to improve the function prediction power of existing motifs. Conclusions FASST contributes a critical feedback and assessment step to existing binding site substructure identification methods and can be used for the thorough investigation of structure-function relationships. The application of MESH allows for an automated

  11. Common substructure in otoacoustic emission spectra of land vertebrates

    Science.gov (United States)

    Manley, Geoffrey A.; Köppl, Christine; Bergevin, Christopher

    2015-12-01

    In humans, a similar spectral periodicity is found in all otoacoustic emission types and in threshold fine structure. This may reflect travelling wave phase and reflectance from "structural roughness" in the organ of Corti, or entrainment and suppressive interactions between emissions. To further understand these phenomena, we have examined spontaneous otoacoustic emission (SOAE) spectra in 9 lizard species and the barn owl and find a comparable periodicity. Importantly, the frequency spacing between SOAE peaks was independent of the physical spacing and of the frequency space constants in hearing organs. In 9 lizard species, median spectral gaps lay between 219 and 461 Hz, with no correlation to papillar length (0.3 to 2.1 mm). Similarly in much longer organs: In humans (35 mm), SOAE spectral gaps vary up to 220 Hz at 4 kHz; in the barn owl (11 mm), the median SOAE peak spacing was 395Hz. In the barn owl, a very large space constant between 5 and 10 kHz (5 mm/octave) contrasts with stable SOAE spacing between 1 and 11 kHz. Similar SOAE spectral gaps across all species suggests they represent a basic frequency grating revealing local phase-dependent interactions between active hair cells, a feature not determined by macro-structural anatomy. Emission spectral spacing is independent of cochlear length, of the frequency space constant, of the existence of travelling waves or of a tectorial membrane. Our data suggest that there are greater similarities between frequency selectivity reflected at the level of the hair cells' spontaneous mechanical output (OAEs) than there are at the level of the auditory nerve, where macro-structural anatomy links hair-cell activity differentially to the neural output. Apparently, all hair-cell arrays show a similar frequency substructure not directly replicated in neural tuning.

  12. Taizhou Yangtze River Bridge

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Taizhou Bridge lies between Taizhou, Zhenjiang and Changzhou City in Jiangsu Province. The total length of Taizhou Bridge is 62.088 kin. The whole line is designed by freeway codes with six lanes in two directions. The wholeinvestment is 9.37 billion RMB and the planned construction duration is 5.5 years. The main bridge crossing the Yangtze River is a continuous three-pylon two-span suspension bridge with the main span of 1 080 m. The bridge system is realized for the first time and ranks first in the world until now.

  13. Formulation of an experimental substructure model using a Craig-Bampton based transmission simulator

    Science.gov (United States)

    Kammer, Daniel C.; Allen, Mathew S.; Mayes, Randy L.

    2015-12-01

    Experimental-analytical substructuring is attractive when there is motivation to replace one or more system subcomponents with an experimental model. This experimentally derived substructure can then be coupled to finite element models of the rest of the structure to predict the system response. The transmission simulator method couples a fixture to the component of interest during a vibration test in order to improve the experimental model for the component. The transmission simulator is then subtracted from the tested system to produce the experimental component. The method reduces ill-conditioning by imposing a least squares fit of constraints between substructure modal coordinates to connect substructures, instead of directly connecting physical interface degrees of freedom. This paper presents an alternative means of deriving the experimental substructure model, in which a Craig-Bampton representation of the transmission simulator is created and subtracted from the experimental measurements. The corresponding modal basis of the transmission simulator is described by the fixed-interface modes, rather than free modes that were used in the original approach. These modes do a better job of representing the shape of the transmission simulator as it responds within the experimental system, leading to more accurate results using fewer modes. The new approach is demonstrated using a simple finite element model based example with a redundant interface.

  14. Strong population substructure is correlated with morphology and ecology in a migratory bat.

    Science.gov (United States)

    Miller-Butterworth, Cassandra M; Jacobs, David S; Harley, Eric H

    2003-07-10

    Examining patterns of inter-population genetic diversity can provide valuable information about both historical and current evolutionary processes affecting a species. Population genetic studies of flying and migratory species such as bats and birds have traditionally shown minimal population substructure, characterized by high levels of gene flow between populations. In general, strongly substructured mammalian populations either are separated by non-traversable barriers or belong to terrestrial species with low dispersal abilities. Species with female philopatry (the tendency to remain in or consistently return to the natal territory) might show strong substructure when examined with maternally inherited mitochondrial DNA, but this substructure generally disappears when biparentally inherited markers are used, owing to male-mediated gene flow. Male-biased dispersal is considered typical for mammals, and philopatry in both sexes is rare. Here we show strong population substructure in a migratory bat species, and philopatry in both sexes, as indicated by concordance of nuclear and mtDNA findings. Furthermore, the genetic structure correlates with local biomes and differentiation in wing morphology. There is therefore a close correlation of genetic and morphological differentiation in sympatric subspecific populations of this mammalian species.

  15. An algebraic sub-structuring method for large-scale eigenvaluecalculation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, C.; Gao, W.; Bai, Z.; Li, X.; Lee, L.; Husbands, P.; Ng, E.

    2004-05-26

    We examine sub-structuring methods for solving large-scalegeneralized eigenvalue problems from a purely algebraic point of view. Weuse the term "algebraic sub-structuring" to refer to the process ofapplying matrix reordering and partitioning algorithms to divide a largesparse matrix into smaller submatrices from which a subset of spectralcomponents are extracted and combined to provide approximate solutions tothe original problem. We are interested in the question of which spectralcomponentsone should extract from each sub-structure in order to producean approximate solution to the original problem with a desired level ofaccuracy. Error estimate for the approximation to the small esteigen pairis developed. The estimate leads to a simple heuristic for choosingspectral components (modes) from each sub-structure. The effectiveness ofsuch a heuristic is demonstrated with numerical examples. We show thatalgebraic sub-structuring can be effectively used to solve a generalizedeigenvalue problem arising from the simulation of an acceleratorstructure. One interesting characteristic of this application is that thestiffness matrix produced by a hierarchical vector finite elements schemecontains a null space of large dimension. We present an efficient schemeto deflate this null space in the algebraic sub-structuringprocess.

  16. Efficient substructure searching of large chemical libraries: the ABCD chemical cartridge.

    Science.gov (United States)

    Agrafiotis, Dimitris K; Lobanov, Victor S; Shemanarev, Maxim; Rassokhin, Dmitrii N; Izrailev, Sergei; Jaeger, Edward P; Alex, Simson; Farnum, Michael

    2011-12-27

    Efficient substructure searching is a key requirement for any chemical information management system. In this paper, we describe the substructure search capabilities of ABCD, an integrated drug discovery informatics platform developed at Johnson & Johnson Pharmaceutical Research & Development, L.L.C. The solution consists of several algorithmic components: 1) a pattern mapping algorithm for solving the subgraph isomorphism problem, 2) an indexing scheme that enables very fast substructure searches on large structure files, 3) the incorporation of that indexing scheme into an Oracle cartridge to enable querying large relational databases through SQL, and 4) a cost estimation scheme that allows the Oracle cost-based optimizer to generate a good execution plan when a substructure search is combined with additional constraints in a single SQL query. The algorithm was tested on a public database comprising nearly 1 million molecules using 4,629 substructure queries, the vast majority of which were submitted by discovery scientists over the last 2.5 years of user acceptance testing of ABCD. 80.7% of these queries were completed in less than a second and 96.8% in less than ten seconds on a single CPU, while on eight processing cores these numbers increased to 93.2% and 99.7%, respectively. The slower queries involved extremely generic patterns that returned the entire database as screening hits and required extensive atom-by-atom verification.

  17. Extreme Brightness Temperatures and Refractive Substructure in 3C273 with RadioAstron

    CERN Document Server

    Johnson, Michael D; Gwinn, Carl R; Gurvits, Leonid I; Narayan, Ramesh; Macquart, Jean-Pierre; Jauncey, David L; Voitsik, Peter A; Anderson, James M; Sokolovsky, Kirill V; Lisakov, Mikhail M

    2016-01-01

    Earth-space interferometry with RadioAstron provides the highest direct angular resolution ever achieved in astronomy at any wavelength. RadioAstron detections of the classic quasar 3C273 on interferometric baselines up to 171,000 km suggest brightness temperatures exceeding expected limits from the "inverse-Compton catastrophe" by two orders of magnitude. We show that at 18 cm, these estimates most probably arise from refractive substructure introduced by scattering in the interstellar medium. We use the scattering properties to estimate an intrinsic brightness temperature of 7*10^12 K, which is consistent with expected theoretical limits, but which is ~15 times lower than estimates that neglect substructure. At 6 cm, the substructure influences the measured values appreciably but gives an estimated brightness temperature that is comparable to models that do not account for the substructure. At 1.3 cm, the substructure does not affect the extremely high inferred brightness temperatures, in excess of 10^13 K....

  18. Reconstruction of small-scale galaxy cluster substructure with lensing flexion

    Science.gov (United States)

    Cain, Benjamin; Bradač, Maruša; Levinson, Rebecca

    2016-09-01

    We present reconstructions of galaxy-cluster-scale mass distributions from simulated gravitational lensing data sets including strong lensing, weak lensing shear, and measurements of quadratic image distortions - flexion. The lensing data is constructed to make a direct comparison between mass reconstructions with and without flexion. We show that in the absence of flexion measurements, significant galaxy-group scale substructure can remain undetected in the reconstructed mass profiles, and that the resulting profiles underestimate the aperture mass in the substructure regions by ˜25 - 40%. When flexion is included, subhaloes down to a mass of ˜3 × 1012 M⊙ can be detected at an angular resolution smaller than 10″. Aperture masses from profiles reconstructed with flexion match the input distribution values to within an error of ˜13%, including both statistical error and scatter. This demonstrates the important constraint that flexion measurements place on substructure in galaxy clusters and its utility for producing high-fidelity mass reconstructions.

  19. Exploring the reality of density substructures in the Palomar 5 stellar stream

    CERN Document Server

    Thomas, Guillaume F; Famaey, Benoit; Martin, Nicolas F; Lewis, Geraint F

    2016-01-01

    We present an analysis of the presence of substructures in the stellar stream of the Palomar 5 globular cluster, as derived from Sloan Digital Sky Survey data. Using a matched filter technique, we recover the positions and sizes of overdensities reported in previous studies. To explore the reality of these structures, we also create an artificial model of the stream, in which we construct a realistic background on top of which we add a perfectly smooth stream structure, taking into account the effects of photometric completeness and interstellar extinction. We find that the smooth artificial stream then shows similarly-pronounced substructures as the real structure. Interestingly, our best-fit N-body simulation does display real projected density variations linked to stellar epicyclic motions, but these become less significant when taking into account the SDSS star-count constraints. The substructures found when applying our matched filter technique to the N-body particles converted into observable stars are ...

  20. Exploring triad-rich substructures by graph-theoretic characterizations in complex networks

    CERN Document Server

    Jia, Songwei; Gao, Yong; Nastos, James; Wen, Xiao; Zhang, Xindong; Wang, Haiyang

    2016-01-01

    One of the most important problems in complex networks is how to detect metadata groups accurately. The main challenge lies in the fact that traditional structural communities do not always capture the intrinsic features of metadata groups. Motivated by the observation that metadata groups in PPI networks tend to consist of an abundance of interacting triad motifs, we define a 2-club substructure with diameter 2 which possessing triad-rich property to describe a metadata group. Based on the triad-rich substructure, we design a DIVision Algorithm using our proposed edge Niche Centrality DIVANC to detect metadata groups effectively in complex networks. We also extend DIVANC to detect overlapping metadata groups by proposing a simple 2-hop overlapping strategy. To verify the effectiveness of triad-rich substructures, we compare DIVANC with existing algorithms on PPI networks, LFR synthetic networks and football networks. The experimental results show that DIVANC outperforms most other algorithms significantly an...

  1. Theory and Simulations of Refractive Substructure in Resolved Scatter-Broadened Images

    CERN Document Server

    Johnson, Michael D

    2015-01-01

    At radio wavelengths, scattering in the interstellar medium distorts the appearance of astronomical sources. Averaged over a scattering ensemble, the result is a blurred image of the source. However, Narayan & Goodman (1989) and Goodman & Narayan (1989) showed that for an incomplete average, scattering introduces refractive substructure in the image of a point source that is both persistent and wideband. We show that this substructure is not smoothed by an extended source and that the scattering can therefore introduce spurious compact features into images that would be resolved in the absence of scattering. In addition, we derive efficient strategies to numerically compute realistic scattered images, and we present characteristic examples from simulations. Our results show that refractive substructure is an important consideration for ongoing missions at the highest angular resolutions, and we discuss specific implications for RadioAstron and the Event Horizon Telescope.

  2. Exploring triad-rich substructures by graph-theoretic characterizations in complex networks

    Science.gov (United States)

    Jia, Songwei; Gao, Lin; Gao, Yong; Nastos, James; Wen, Xiao; Zhang, Xindong; Wang, Haiyang

    2017-02-01

    One of the most important problems in complex networks is how to detect communities accurately. The main challenge lies in the fact that traditional definition about communities does not always capture the intrinsic features of communities. Motivated by the observation that communities in PPI networks tend to consist of an abundance of interacting triad motifs, we define a 2-club substructure with diameter 2 possessing triad-rich property to describe a community. Based on the triad-rich substructure, we design a DIVision Algorithm using our proposed edge Niche Centrality DIVANC to detect communities effectively in complex networks. We also extend DIVANC to detect overlapping communities by proposing a simple 2-hop overlapping strategy. To verify the effectiveness of triad-rich substructures, we compare DIVANC with existing algorithms on PPI networks, LFR synthetic networks and football networks. The experimental results show that DIVANC outperforms most other algorithms significantly and, in particular, can detect sparse communities.

  3. Sustainable Bridge Infrastructure Procurement

    DEFF Research Database (Denmark)

    Safi, Mohammed; Du, Guangli; Simonsson, Peter

    2016-01-01

    The lack of a flexible but systematic approach for integrating lifecycle aspects into bridge investment decisions is a major obstacle hindering the procurement of sustainable bridge infrastructures. This paper addresses this obstacle by introducing a holistic approach that agencies could use...... to procure the most “sustainable” (lifecycle-efficient) bridge through a fair design-build (D-B) tendering process, considering all the main aspects: life-cycle cost (LCC), service life-span, aesthetic demands and environmental impacts (LCA)....

  4. Bridge Crossing Simulator

    Science.gov (United States)

    2014-10-07

    Requirement BCS Computer-controlled hydraulic actuation system to impart simulated crossing loads on an entire bridge structure undergoing fatigue test ...structure. Bridge test site with prepared embankments corresponding to the span and bank condition requirements of the bridge under test Conduct real...Center (AEC). (5) Sample size and number of crossings required. The number of required simulated crossings to conduct fatigue testing per the

  5. On the Role of Triadic Substructures in Complex Networks

    CERN Document Server

    Winkler, Marco

    2016-01-01

    In the course of the growth of the Internet and due to increasing availability of data, over the last two decades, the field of network science has established itself as an own area of research. With quantitative scientists from computer science, mathematics, and physics working on datasets from biology, economics, sociology, political sciences, and many others, network science serves as a paradigm for interdisciplinary research. One of the major goals in network science is to unravel the relationship between topological graph structure and a network's function. As evidence suggests, systems from the same fields, i.e. with similar function, tend to exhibit similar structure. However, it is still vague whether a similar graph structure automatically implies likewise function. This dissertation aims at helping to bridge this gap, while particularly focusing on the role of triadic structures. After a general introduction to the main concepts of network science, existing work devoted to the relevance of triadic s...

  6. Bridging the Gap

    OpenAIRE

    Kramer Overgaard, Majken; Broeng, Jes; Jensen, Monika Luniewska; Murdock, Karen; Schmidt, Iben Julie

    2015-01-01

    Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures. Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ve...

  7. Bridging the Gap

    DEFF Research Database (Denmark)

    Kramer Overgaard, Majken; Broeng, Jes; Jensen, Monika Luniewska;

    Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures.......Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures....

  8. Semiconductor bridge (SCB) detonator

    Science.gov (United States)

    Bickes, Jr., Robert W.; Grubelich, Mark C.

    1999-01-01

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

  9. Performance of Jet Substructure Techniques and Boosted Object Identification in ATLAS

    CERN Document Server

    Lacey, J; The ATLAS collaboration

    2014-01-01

    ATLAS has implemented and commissioned many new jet substructure techniques to aid in the identification and interpretation of hadronic final states originating from Lorentz-boosted heavy particles produced at the LHC. These techniques include quantum jets, jet charge, jet shapes, quark/gluon, boosted boson and top quark tagging, along with grooming methods such as pruning, trimming, and filtering. These techniques have been validated using the large 2012 ATLAS dataset. Presented here is a summary of the state of the art jet substructure and tagging techniques developed in ATLAS, their performance and recent results.

  10. VARIATION OF SUBSTRUCTURES OF PEARLITIC HEAT RESISTANT STEEL AFTER HIGH TEMPERATURE AGING

    Institute of Scientific and Technical Information of China (English)

    R.C.Yang; K.Chen; H.X.Feng; H.Wang

    2004-01-01

    The observations of dislocations, substructures and other microstructural details were conducted mainly by means of transmission electron microscope (TEM) and scanning electron microscope (SEM) for 12Cr1Mo V pearlitic heat-resistant steel. It is shown that during the high temperature long-term aging, the disordered and jumbled phasetransformed dislocations caused by normalized cooling are recovered and rearranged into cell substructures, and then the dislocation density is reduced gradually. Finally a low density linear dislocation configuration and a stabler dislocation network are formed and ferritic grains grow considerably.

  11. Jet Substructure Templates: Data-driven QCD Backgrounds for Fat Jet Searches

    CERN Document Server

    Cohen, Timothy; Lisanti, Mariangela; Lou, Hou Keong; Wacker, Jay G

    2014-01-01

    QCD is often the dominant background to new physics searches for which jet substructure provides a useful handle. Due to the challenges associated with modeling this background, data-driven approaches are necessary. This paper presents a novel method for determining QCD predictions using templates -- probability distribution functions for jet substructure properties as a function of kinematic inputs. Templates can be extracted from a control region and then used to compute background distributions in the signal region. Using Monte Carlo, we illustrate the procedure with two case studies and show that the template approach effectively models the relevant QCD background. This work strongly motivates the application of these techniques to LHC data.

  12. Jet substructure templates: data-driven QCD backgrounds for fat jet searches

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, Timothy [Theory Group, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Jankowiak, Martin [Institut für Theoretische Physik, Universität Heidelberg, 69120 Heidelberg (Germany); Lisanti, Mariangela; Lou, Hou Keong [Physics Department, Princeton University, Princeton, NJ 08544 (United States); Wacker, Jay G. [Theory Group, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States)

    2014-05-05

    QCD is often the dominant background to new physics searches for which jet substructure provides a useful handle. Due to the challenges associated with modeling this background, data-driven approaches are necessary. This paper presents a novel method for determining QCD predictions using templates — probability distribution functions for jet substructure properties as a function of kinematic inputs. Templates can be extracted from a control region and then used to compute background distributions in the signal region. Using Monte Carlo, we illustrate the procedure with two case studies and show that the template approach effectively models the relevant QCD background. This work strongly motivates the application of these techniques to LHC data.

  13. OPTIMAL SUBSTRUCTURE OF SET-VALUED SOLUTIONS OF NORMAL-FORM GAMES AND COORDINATION

    Institute of Scientific and Technical Information of China (English)

    Norimasa KOBAYASHI; Kyoichi KIJIMA

    2009-01-01

    A number of solution concepts of normal-form games have been proposed in the literature on subspaces of action profiles that have Nash type stability. While the literature mainly focuses on the minimal of such stable subspaces, this paper argues that non-minimal stable subspaces represent well the multi-agent situations to which neither Nash equilibrium nor rationalizability may be applied with satisfaction. As a theoretical support, the authors prove the optimal substructure of stable subspaces regarding the restriction of a game. It is further argued that the optimal substructure characterizes hierarchical diversity of coordination and interim phases in learning.

  14. Damage investigation of girder bridges under the Wenchuan earthquake and corresponding seismic design recommendations

    Institute of Scientific and Technical Information of China (English)

    Li Jianzhong; Peng Tianbo; Xu yan

    2008-01-01

    An investigation of girder bridges on National Highway 213 and the Doujiangyan-Wenchuan expressway after the Wenchuan earthquake showed that typical types of damage included:span collapses due to unseating at expansion joints;shear key failure;and damage of the expansion joint due to the slide-induced large relative displacement between the bottom of the girder and the top of the laminated-rubber bearing.This slide,however,can actually act as a form of isolation for the substructure,and as a result,the piers and foundation of most of the bridges on state route 213 suffered minor damage.The exception was the Baihua Bridge,which suffered severe damage.Corresponding seismic design recommendations are presented based on this investigation.

  15. A Substructural Damage Identification Approach for Shear Structure Based on Changes in the First AR Model Coefficient Matrix

    Directory of Open Access Journals (Sweden)

    Liu Mei

    2015-01-01

    Full Text Available A substructural damage identification approach based on changes in the first AR model coefficient matrix is proposed in this paper to identify structural damage including its location and severity. Firstly, a substructure approach is adopted in the procedure to divide a complete structure into several substructures in order to significantly reduce the number of unknown parameters for each substructure so that damage identification processes can be independently conducted on each substructure. To establish a relation between changes in AR model coefficients and structural damage for each substructure, a theoretical derivation is presented. Thus the accelerations are fed into ARMAX models to determine the AR model coefficients for each substructure under undamaged and various damaged conditions, based on which changes in the first AR model coefficient matrix (CFAR is obtained and adopted as the damage indicator for the proposed substructure damage identification approach. To better assess the performance of the proposed procedure, a numerical simulation and an experimental verification of the proposed approach are then carried out and the results show that the proposed procedure can successfully locate and quantify the damage in both simulation and laboratory experiment.

  16. Principles of Bridge Reliability

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Nowak, Andrzej S.

    The paper gives a brief introduction to the basic principles of structural reliability theory and its application to bridge engineering. Fundamental concepts like failure probability and reliability index are introduced. Ultimate as well as serviceability limit states for bridges are formulated...

  17. Property Graph vs RDF Triple Store: A Comparison on Glycan Substructure Search.

    Directory of Open Access Journals (Sweden)

    Davide Alocci

    Full Text Available Resource description framework (RDF and Property Graph databases are emerging technologies that are used for storing graph-structured data. We compare these technologies through a molecular biology use case: glycan substructure search. Glycans are branched tree-like molecules composed of building blocks linked together by chemical bonds. The molecular structure of a glycan can be encoded into a direct acyclic graph where each node represents a building block and each edge serves as a chemical linkage between two building blocks. In this context, Graph databases are possible software solutions for storing glycan structures and Graph query languages, such as SPARQL and Cypher, can be used to perform a substructure search. Glycan substructure searching is an important feature for querying structure and experimental glycan databases and retrieving biologically meaningful data. This applies for example to identifying a region of the glycan recognised by a glycan binding protein (GBP. In this study, 19,404 glycan structures were selected from GlycomeDB (www.glycome-db.org and modelled for being stored into a RDF triple store and a Property Graph. We then performed two different sets of searches and compared the query response times and the results from both technologies to assess performance and accuracy. The two implementations produced the same results, but interestingly we noted a difference in the query response times. Qualitative measures such as portability were also used to define further criteria for choosing the technology adapted to solving glycan substructure search and other comparable issues.

  18. Property Graph vs RDF Triple Store: A Comparison on Glycan Substructure Search.

    Science.gov (United States)

    Alocci, Davide; Mariethoz, Julien; Horlacher, Oliver; Bolleman, Jerven T; Campbell, Matthew P; Lisacek, Frederique

    2015-01-01

    Resource description framework (RDF) and Property Graph databases are emerging technologies that are used for storing graph-structured data. We compare these technologies through a molecular biology use case: glycan substructure search. Glycans are branched tree-like molecules composed of building blocks linked together by chemical bonds. The molecular structure of a glycan can be encoded into a direct acyclic graph where each node represents a building block and each edge serves as a chemical linkage between two building blocks. In this context, Graph databases are possible software solutions for storing glycan structures and Graph query languages, such as SPARQL and Cypher, can be used to perform a substructure search. Glycan substructure searching is an important feature for querying structure and experimental glycan databases and retrieving biologically meaningful data. This applies for example to identifying a region of the glycan recognised by a glycan binding protein (GBP). In this study, 19,404 glycan structures were selected from GlycomeDB (www.glycome-db.org) and modelled for being stored into a RDF triple store and a Property Graph. We then performed two different sets of searches and compared the query response times and the results from both technologies to assess performance and accuracy. The two implementations produced the same results, but interestingly we noted a difference in the query response times. Qualitative measures such as portability were also used to define further criteria for choosing the technology adapted to solving glycan substructure search and other comparable issues.

  19. Substructure formation during pattern transposition from substrate into polymer blend film

    NARCIS (Netherlands)

    Cyganik, P; Budkowski, A; Steiner, U; Rysz, J; Bernasik, A; Walheim, S; Postawa, Z; Raczkowska, J

    2003-01-01

    A chemical pattern on a substrate is transposed into thin films of a ternary polymer blend during spin-casting from a common solvent. One of the blend components intercalates at interfaces between the other two phases to reduce their interfacial energy. As a result, an extensive substructure is form

  20. Structure and substructure of austenite formed during heating of quenched and thermomechanically strengthened steels

    Energy Technology Data Exchange (ETDEWEB)

    Bernshtejn, M.L.; Kaputkina, L.M.; Prokoshkin, S.D.; Lyuttsau, A.V.; Prokoshkina, V.G. (Moskovskij Inst. Stali i Splavov (USSR))

    1982-06-01

    Mechanism of ..cap alpha.. ..-->.. ..gamma.. transformation in chromium and chromium-nickel steels, peculiarities of substructure formation of austenite formed at repeated heating after quenching and high-temperature thermomechanical treatment and its stability to recrystallization in steels with different martensite morphology and temperature of the initial stage of austenite formation are investigated.

  1. A New Method to Quantify X-ray Substructures in Clusters of Galaxies

    CERN Document Server

    Andrade-Santos, Felipe; Laganá, Tatiana Ferraz

    2011-01-01

    We present a new method to quantify substructures in clusters of galaxies, based on the analysis of the intensity of structures. This analysis is done in a residual image that is the result of the subtraction of a surface brightness model, obtained by fitting a two-dimensional analytical model (beta-model or S\\'ersic profile) with elliptical symmetry, from the X-ray image. Our method is applied to 34 clusters observed by the Chandra Space Telescope that are in the redshift range 0.02substructure level with physical quantities, such as the mass, X-ray luminosity, temperature, and cluster redshift. We use our method to separate the clusters in two sub-samples of high and low substructure levels. We conclude, using Monte Carlo simulations, that the method recuperates very well the true amount of substructure for small angular core radii clusters (with respect to the whole image s...

  2. Quantifying Substructure Measures In X-ray Images of Galaxy Cluster Mergers With SLAM

    Science.gov (United States)

    Chatzikos, Marios; Sarazin, C. L.; O'Shea, B. W.

    2014-01-01

    I use the Simulation Library of Astrophysical galaxy cluster Mergers (SLAM) database to quantify the effects of mergers on X-ray observables. SLAM consists of a set of 156 adiabatic simulations of binary galaxy cluster mergers, that covers 2 orders of magnitude in the mass of the primary cluster, four values for the mass contrast, and four values for the angular momentum of the collision. In this talk I describe results on substructure measures obtained for various viewing angles. I have quantified the substructure in X-ray images using both center shifts and power ratios. Mergers of intermediate mass contrasts produce substructure signals that can persist in X-ray images for at least 1-2 sound crossing times. The amplitude of both measures depends strongly on the initial mass contrast. The measures for major mergers (mass contrast less than 3) appear to depend on the system mass, while for minor mergers (mass contrast between 3 and 10) they are generally independent of the system mass. Neither measure reflects the true dynamical state of the system closely, although the center shifts appear to be a better proxy. Comparisons with the virial and hydrostatic disequilibrium parameters reveal that there is no value of either substructure measure that unambiguously distinguishes merging from relaxing systems. Implications for SZE observations will also be discussed.

  3. Placing Limits on Extragalactic Substructure with Gravitational Lenses and Adaptive Optics

    NARCIS (Netherlands)

    Lagattuta, David J.; Vegetti, S.; Auger, M. W.; Fassnacht, C. D.; Koopmans, L. V. E.; McKean, J. P.

    2011-01-01

    We present the first results from a systematic search for extragalactic substructure, using high resolution Adaptive Optics (AO) images of known strong gravitational lenses. In particular we focus on two lens systems, B0128+437 and B1939+666, placing limits on both luminous and dark matter substruct

  4. Genetic sub-structure in western Mediterranean populations revealed by 12 Y-chromosome STR loci

    DEFF Research Database (Denmark)

    Rodríguez, V; Tomas Mas, Carmen; Sánchez, J J;

    2008-01-01

    .9988 +/- 0.0002. These Y-STRs markers showed a low capacity of discrimination (56.3%) in the Ibiza population probably due to genetic drift. Comparisons between the populations studied and other neighbouring populations showed a clear genetic sub-structure in the western Mediterranean area....

  5. Can galactic dark matter substructure contribute to the cosmic gamma-ray anisotropy?

    CERN Document Server

    Lange, J U

    2014-01-01

    The annihilation of dark matter (DM) particles in the Milky Way can contribute to the diffuse gamma-ray background (DGRB). Due to the presence of substructures, this emission will appear anisotropic in a predictable way. We generate full-sky maps of the gamma-ray emission in galactic substructures from results of the high-resolution Via Lactea II N-body simulation of the Milky Way DM halo. We calculate the anisotropy pattern, taking into account different radial profiles of the DM distribution in substructures, cosmic variance, and the detection threshold, and compare it to the anisotropy in the DGRB observed by the Fermi Large Area Telescope (LAT). By comparing the upper limits on the DM self-annihilation cross-section, , implied by the anisotropy to the intensity of the DGRB and detected sources in the LAT 2-yr Point Source Catalog, we find that galactic substructure cannot contribute to the anisotropies in the DGRB without strongly violating these observations. Our results challenge the perception that sma...

  6. Substructure method of soil-structure interaction analysis for earthquake loadings

    Energy Technology Data Exchange (ETDEWEB)

    Park, H. G.; Joe, Y. H. [Industrial Development Research Center, Univ. of Incheon, Incheon (Korea, Republic of)

    1997-07-15

    Substructure method has been preferably adopted for soil-structure interaction analysis because of its simplicity and economy in practical application. However, substructure method has some limitation in application and does not always give reliable results especially for embedded structures or layered soil conditions. The objective of this study to validate the reliability of the soil-structure interaction analysis results by the proposed substructure method using lumped-parameter model and suggest a method of seismic design of nuclear power plant structures with specific design conditions. In this study, theoretic background and modeling technique of soil-structure interaction phenomenon have been reviewed and an analysis technique based on substructure method using lumped-parameter model has been suggested. The practicality and reliability of the proposed method have been validated through the application of the method to the seismic analysis of the large-scale seismic test models. A technical guide for practical application and evaluation of the proposed method have been also provided through the various type parametric.

  7. Free-Interface Dual-Compatibility Modal Synthesis Substructure Method in Large-Scale Structures

    Institute of Scientific and Technical Information of China (English)

    Peng Guihan彭桂瀚; Lin Wei林伟; Chen Shanghong陈尚鸿; Yu Jiexin余洁歆

    2015-01-01

    Free-interface dual-compatibility modal synthesis method(compatibility of both force and displacement on interfaces)is introduced to large-scale civil engineering structure to enhance computation efficiency. The basic equations of the method are first set up, and then the mode cut-off principle and the dividing principle are proposed. MATLAB is used for simulation in different frame structures. The simulation results demonstrate the applicability of this substructure method to civil engineering structures and the correctness of the proposed mode cut-off princi-ple. Studies are also conducted on how to divide the whole structure for better computation efficiency while main-taining better precision. It is observed that the geometry and material properties should be considered, and the syn-thesis results would be more precise when the inflection points of the mode shapes are taken into consideration. Furthermore, the simulation performed on a large-scale high-rise connected structure further proves the feasibility and efficiency of this modal synthesis method compared with the traditional global method. It is also concluded from the simulation results that the fewer number of DOFs in each substructure will result in better computation efficiency, but too many substructures will be time-consuming due to the tedious synthesis procedures. Moreover, the substructures with free interface will introduce errors and reduce the precision dramatically, which should be avoided.

  8. The development of microtextures and dislocation substructures in naturally deformed olivines from various geological environments

    NARCIS (Netherlands)

    Buiskool Toxopeus, J.M.A.

    1978-01-01

    High voltage electron microscopy and petrofabric analysis techniques are used to distinguish dislocation substructures and preferred orientation patterns of the mineral olivine in naturally deformed peridotites. In order to obtain information over a wide field in which different types of deformation

  9. Updating failure probability of a welded joint in offshore wind turbine substructures

    DEFF Research Database (Denmark)

    Mai, Quang A.; Sørensen, John Dalsgaard; Rigo, Philippe

    2016-01-01

    The operation and maintenance cost of offshore wind turbine substructures contributes significantly in the cost of a kWh. That cost may be lowered by application of reliability- and risk based maintenance strategies and reliability updating based on inspections performed during the design lifetim...

  10. Rapid impact testing for quantitative assessment of large populations of bridges

    Science.gov (United States)

    Zhou, Yun; Prader, John; DeVitis, John; Deal, Adrienne; Zhang, Jian; Moon, Franklin; Aktan, A. Emin

    2011-04-01

    Although the widely acknowledged shortcomings of visual inspection have fueled significant advances in the areas of non-destructive evaluation and structural health monitoring (SHM) over the last several decades, the actual practice of bridge assessment has remained largely unchanged. The authors believe the lack of adoption, especially of SHM technologies, is related to the 'single structure' scenarios that drive most research. To overcome this, the authors have developed a concept for a rapid single-input, multiple-output (SIMO) impact testing device that will be capable of capturing modal parameters and estimating flexibility/deflection basins of common highway bridges during routine inspections. The device is composed of a trailer-mounted impact source (capable of delivering a 50 kip impact) and retractable sensor arms, and will be controlled by an automated data acquisition, processing and modal parameter estimation software. The research presented in this paper covers (a) the theoretical basis for SISO, SIMO and MIMO impact testing to estimate flexibility, (b) proof of concept numerical studies using a finite element model, and (c) a pilot implementation on an operating highway bridge. Results indicate that the proposed approach can estimate modal flexibility within a few percent of static flexibility; however, the estimated modal flexibility matrix is only reliable for the substructures associated with the various SIMO tests. To overcome this shortcoming, a modal 'stitching' approach for substructure integration to estimate the full Eigen vector matrix is developed, and preliminary results of these methods are also presented.

  11. Identification of population substructure among Jews using STR markers and dependence on reference populations included

    Directory of Open Access Journals (Sweden)

    Mutirangura Apiwat

    2010-06-01

    Full Text Available Abstract Background Detecting population substructure is a critical issue for association studies of health behaviors and other traits. Whether inherent in the population or an artifact of marker choice, determining aspects of a population's genetic history as potential sources of substructure can aid in design of future genetic studies. Jewish populations, among which association studies are often conducted, have a known history of migrations. As a necessary step in understanding population structure to conduct valid association studies of health behaviors among Israeli Jews, we investigated genetic signatures of this history and quantified substructure to facilitate future investigations of these phenotypes in this population. Results Using 32 autosomal STR markers and the program STRUCTURE, we differentiated between Ashkenazi (AJ, N = 135 and non-Ashkenazi (NAJ, N = 226 Jewish populations in the form of Northern and Southern geographic genetic components (AJ north 73%, south 23%, NAJ north 33%, south 60%. The ability to detect substructure within these closely related populations using a small STR panel was contingent on including additional samples representing major continental populations in the analyses. Conclusions Although clustering programs such as STRUCTURE are designed to assign proportions of ancestry to individuals without reference population information, when Jewish samples were analyzed in the absence of proxy parental populations, substructure within Jews was not detected. Generally, for samples with a given grandparental country of birth, STRUCTURE assignment values to Northern, Southern, African and Asian clusters agreed with mitochondrial DNA and Y-chromosomal data from previous studies as well as historical records of migration and intermarriage.

  12. Bridge technology report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. As LANs have proliferated, new technologies and system concepts have come to the fore. One of the key issues is how to interconnect networks. One means of interconnection is to use a 'bridge'. Other competing technologies are repeaters, routers, and gateways. Bridges permit traffic isolation, connect network segments together and operate at the MAC layer. Further, because they operate at the MAC layer, they can handle a variety of protocols such as TCP/IP, SNA, and X.25. This report focuses on the specific technology of bridging two netw

  13. Numerical Hybrid Simulation Modeling Verification for a Curved 3-Pier Bridge (Investigation of Combined Actions on Reinforced Concrete Bridge Piers (CABER Project

    Directory of Open Access Journals (Sweden)

    Adel Abdelnaby

    2013-06-01

    Full Text Available Reinforced concrete bridge piers are subjected to complex loading conditions under earthquake ground motions. Bridge geometric irregularities and asymmetries result in combined actions imposed on the piers as a combination of displacements and rotations in all six degrees of freedom at the pier-deck juncture. Existing analytical tools have proven their inadequacy in representing the actual behavior of piers under these combined actions, particularly in their inelastic range. The objective of this investigation is to develop a fundamental understanding of the effects of these combined actions on the performance of RC piers and the resulting system response. This paper describes a part of the CABER project that verifies the numerical hybrid simulation of the curved bridge. In this part two models were introduced, a whole model and a sub-structured hybrid model. The whole model was established using the Zeus-NL analysis platform, which is capable of performing inelastic nonlinear response history analysis of the whole curved bridge. The hybrid model was divided into three modules which comprised the deck, left and right piers, and the middle pier of the bridge. The three modules were modeled by Zeus-NL as a static analysis module interface. The simulation coordinator (SimCor software was utilized to communicate between these modules using a Pseudo-Dynamic time integration scheme. Results obtained from both models were compared and conclusions were drawn.

  14. Bridged Race Population Estimates

    Data.gov (United States)

    U.S. Department of Health & Human Services — Population estimates from "bridging" the 31 race categories used in Census 2000, as specified in the 1997 Office of Management and Budget (OMB) race and ethnicity...

  15. Bridging Humanism and Behaviorism.

    Science.gov (United States)

    Chu, Lily

    1980-01-01

    Humanistic behaviorism may provide the necessary bridge between behaviorism and humanism. Perhaps the most humanistic approach to teaching is to learn how certain changes will help students and how these changes can be accomplished. (Author/MLF)

  16. Germ Cell Intercellular Bridges

    Science.gov (United States)

    Greenbaum, Michael P.; Iwamori, Tokuko; Buchold, Gregory M.; Matzuk, Martin M.

    2011-01-01

    Stable intercellular bridges are a conserved feature of gametogenesis in multicellular animals observed more than 100 years ago, but their function was unknown. Many of the components necessary for this structure have been identified through the study of cytokinesis in Drosophila; however, mammalian intercellular bridges have distinct properties from those of insects. Mammalian germ cell intercellular bridges are composed of general cytokinesis components with additional germ cell–specific factors including TEX14. TEX14 is an inactive kinase essential for the maintenance of stable intercellular bridges in gametes of both sexes but whose loss specifically impairs male meiosis. TEX14 acts to impede the terminal steps of abscission by competing for essential component CEP55, blocking its interaction in nongerm cells with ALIX and TSG101. Additionally, TEX14-interacting protein RBM44, whose localization in stabile intercellular bridges is limited to pachytene and secondary spermatocytes, may participate in processes such as RNA transport but is nonessential to the maintenance of intercellular bridge stability. PMID:21669984

  17. Long Span Bridges in Scandinavia

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1998-01-01

    The first Scandinavian bridge with a span of more than 500 m was the Lillebælt Suspension Bridge opened to traffic in 1970.Art the end of the 20th century the longest span of any European bridge is found in the Storebælt East Bridge with a main span of 1624 m. Also the third longest span in Europe...... is found in Scandinavia - the 1210 m span of the Höga Kusten Bridge in Sweden.The Kvarnsund Bridge in Norway was at the completion in 1991 the longest cable-stayed bridge in the world, and the span of 530 m is still thge longest for cable-stayed bridges in concrete. The Øresund Bridge with its sapn of 490...... m is the longest among cable-stayed bridges for both road and railway traffic....

  18. New Constraints on the Complex Mass Substructure in Abell 1689 from Gravitational Flexion

    CERN Document Server

    Leonard, Adrienne; Goldberg, David M

    2010-01-01

    In a recent publication, the flexion aperture mass statistic was found to provide a robust and effective method by which substructure in galaxy clusters might be mapped. Moreover, we suggested that constraints on the masses and mass profile of structures might be constrained using this method. In this paper, we apply the flexion aperture mass technique to HST ACS images of Abell 1689. We compare this measure to the weak lensing shear aperture mass statistic, and demonstrate that the flexion aperture mass statistic is more sensitive to structures on the scales considered, dramatically outperforming the shear aperture mass statistic on this dataset, which suffers from persistent systematic noise. While the central potential is not constrained by our method, due largely to missing data in the central 0.5$^\\prime$ of the cluster, we are able to place constraints on the masses and mass profiles of prominent substructures. Considering 16 flexion aperture mass reconstructions, we identify 4 separate mass peaks, and ...

  19. A substructure inside spiral arms, and a mirror image across the Galactic Meridian

    CERN Document Server

    Vallee, Jacques P

    2016-01-01

    While the galactic density wave theory is over 50 years old and well known in science, whether it fits our own Milky Way disk has been difficult to say. Here we show a substructure inside the spiral arms. This substructure is reversing with respect to the Galactic Meridian (longitude zero), and crosscuts of the arms at negative longitudes appear as mirror images of crosscuts of the arms at positive longitudes. Four lanes are delineated: mid-arm (extended 12CO gas at mid arm, HI atoms), in-between offset by about 100 pc (synchrotron, radio recombination lines), in between offset by about 200 pc (masers, colder dust), and inner edge (hotter dust seen in Mid-IR and Near-IR).

  20. Development and Demonstration of a Magnesium-Intensive Vehicle Front-End Substructure

    Energy Technology Data Exchange (ETDEWEB)

    Logan, Stephen D. [United States Automotive Materials Partnership LLC, Southfield, MI (United States); Forsmark, Joy H. [United States Automotive Materials Partnership LLC, Southfield, MI (United States); Osborne, Richard [United States Automotive Materials Partnership LLC, Southfield, MI (United States)

    2016-07-01

    This project is the final phase (designated Phase III) of an extensive, nine-year effort with the objectives of developing a knowledge base and enabling technologies for the design, fabrication and performance evaluation of magnesium-intensive automotive front-end substructures intended to partially or completely replace all-steel comparators, providing a weight savings approaching 50% of the baseline. Benefits of extensive vehicle weight reduction in terms of fuel economy increase, extended vehicle range, vehicle performance and commensurate reductions in greenhouse gas emissions are well known. An exemplary vehicle substructure considered by the project is illustrated in Figure 1, along with the exterior vehicle appearance. This unibody front-end “substructure” is one physical objective of the ultimate design and engineering aspects established at the outset of the larger collective effort.

  1. Twisting phonons in complex crystals with quasi-one-dimensional substructures.

    Science.gov (United States)

    Chen, Xi; Weathers, Annie; Carrete, Jesús; Mukhopadhyay, Saikat; Delaire, Olivier; Stewart, Derek A; Mingo, Natalio; Girard, Steven N; Ma, Jie; Abernathy, Douglas L; Yan, Jiaqiang; Sheshka, Raman; Sellan, Daniel P; Meng, Fei; Jin, Song; Zhou, Jianshi; Shi, Li

    2015-04-15

    A variety of crystals contain quasi-one-dimensional substructures, which yield distinctive electronic, spintronic, optical and thermoelectric properties. There is a lack of understanding of the lattice dynamics that influences the properties of such complex crystals. Here we employ inelastic neutron scatting measurements and density functional theory calculations to show that numerous low-energy optical vibrational modes exist in higher manganese silicides, an example of such crystals. These optical modes, including unusually low-frequency twisting motions of the Si ladders inside the Mn chimneys, provide a large phase space for scattering acoustic phonons. A hybrid phonon and diffuson model is proposed to explain the low and anisotropic thermal conductivity of higher manganese silicides and to evaluate nanostructuring as an approach to further suppress the thermal conductivity and enhance the thermoelectric energy conversion efficiency. This discovery offers new insights into the structure-property relationships of a broad class of materials with quasi-one-dimensional substructures for various applications.

  2. Fast and accurate protein substructure searching with simulated annealing and GPUs

    Directory of Open Access Journals (Sweden)

    Stivala Alex D

    2010-09-01

    Full Text Available Abstract Background Searching a database of protein structures for matches to a query structure, or occurrences of a structural motif, is an important task in structural biology and bioinformatics. While there are many existing methods for structural similarity searching, faster and more accurate approaches are still required, and few current methods are capable of substructure (motif searching. Results We developed an improved heuristic for tableau-based protein structure and substructure searching using simulated annealing, that is as fast or faster and comparable in accuracy, with some widely used existing methods. Furthermore, we created a parallel implementation on a modern graphics processing unit (GPU. Conclusions The GPU implementation achieves up to 34 times speedup over the CPU implementation of tableau-based structure search with simulated annealing, making it one of the fastest available methods. To the best of our knowledge, this is the first application of a GPU to the protein structural search problem.

  3. The Aspen Framework for Dark Matter Substructure Inference from Strong Gravitational Lensing Observations

    Science.gov (United States)

    Moustakas, Leonidas A.; Cyr-Racine, Francis-Yan; Keeton, Charles R.

    2016-01-01

    The properties of the dark matter particle or particles lead to different small scale halo populations, distributions, and evolution over cosmic time. We introduce a new method for characterizing the properties of substructure within galaxies through the power spectrum of potential fluctuations, and demonstrate how complete sets of multiwavelength imaging and time domain observations can be processed directly to infer all facets of the strong gravitational lensing components and source properties, including the dark matter substructure power spectrum constraints. We are able to take advantage of analysis parallels with cosmic background radiation techniques, and furthermore demonstrate how this technique, dubbed The Aspen Framework, reduces to the long-standing approach of working with reduced or derived observable quantities in lensing.

  4. Factorization for groomed jet substructure beyond the next-to-leading logarithm

    CERN Document Server

    Frye, Christopher; Schwartz, Matthew D; Yan, Kai

    2016-01-01

    Jet grooming algorithms are widely used in experimental analyses at hadron colliders to remove contaminating radiation from within jets. While the algorithms perform a great service to the experiments, their intricate algorithmic structure and multiple parameters has frustrated precision theoretic understanding. In this paper, we demonstrate that one particular groomer called soft drop actually makes precision jet substructure easier. In particular, we derive a factorization formula for a large class of soft drop jet substructure observables, including jet mass. The essential observation that allows for this factorization is that, without the soft wide-angle radiation groomed by soft drop, all singular contributions are collinear. The simplicity and universality of the collinear limit in QCD allows us to show that to all orders, the normalized differential cross section has no contributions from non-global logarithms. It is also independent of process, up to the relative fraction of quark and gluon jets. In f...

  5. Ring and jet study on the azimuthal substructure of pions at CERN SPS energy

    Indian Academy of Sciences (India)

    Prabir Kumar Haldar; Sanjib Kumar Manna; Prosenjit Saha; Dipak Ghosh

    2013-04-01

    We have presented an investigation on the ring- and jet-like azimuthal angle sub-structures in the emission of secondary charged hadrons coming from 32S–Ag/Br interactions at 200 A GeV/c. Nuclear photographic emulsion technique has been employed to collect the experimental data. The presence of such substructures, their average behaviour, their size, and their position of occurrence have been examined. The experimental results have also been compared with the results simulated by Monte-Carlo method. The analysis strongly indicates the presence of ring- and jet-like structures in the experimental distributions of particles beyond statistical noise. The experimental results are in good agreement with I M Dremin idea, that the phenomenon is similar to the emission of Cherenkov electromagnetic radiation.

  6. Damage detection test of a substructure model of the National Swimming Center

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to detect the damage locations of complex spatial structures, a sensor region-based damage detection approach was developed based on the damage locating vectors method. A normalized damage locating index was introduced to identify the damage regions. An experiment on damage detection of a substructure model of the National Swimming Center ’Water Cube’ was carried out. Two damage patterns were involved in the experiment. The test model was excited by using hammer impacts. Acceleration responses of the undamaged and damaged structure model were measured. Modal parameters were identified from the acceleration responses by utilizing the eigensystem realization algorithm (ERA). By using the developed sensor region-based method, the damage regions of the substructure model were located. The results show that the proposed method is able to effec- tively locate the damage regions.

  7. Performance of large-R jets and jet substructure reconstruction with the ATLAS detector

    CERN Document Server

    The ATLAS collaboration

    2012-01-01

    This paper presents the application of techniques to study jet substructure. The performance of modified jet algorithms for a variety of jet types and event topologies is investigated. Properties of jets subjected to the mass-drop filtering, trimming and pruning algorithms are found to have a reduced sensitivity to multiple proton-proton interactions and exhibit improved stability at high luminosity. Monte Carlo studies of the signal-background discrimination with jet grooming in new physics searches based on jet invariant mass and jet substructure properties are also presented. The application of jet trimming is shown to improve the robustness of large-R jet measurements, reduce sensitivity to the superfluous effects due to the intense environment of the high luminosity LHC, and improve the physics potential of searches for heavy boosted objects. The analyses presented in this note use the full 2011 ATLAS dataset, corresponding to an integrated luminosity of 4.7 \\pm 0.2 fb−1 .

  8. Prefabricated floor panels composed of fiber reinforced concrete and a steel substructure

    DEFF Research Database (Denmark)

    Lárusson, Lárus H.; Fischer, Gregor; Jönsson, Jeppe

    2013-01-01

    loading at the serviceability and ultimate limit states. The composite construction concept offers flexibility in the assembly process, the ability to adapt to various load and boundary requirements, and efficient utilization of material properties that result in a light weight prefabricated structural......This paper reports on a study on prefabricated composite and modular floor deck panels composed of relatively thin fiber reinforced concrete slabs connected to steel substructures. The study focuses on the design, manufacturing, structural improvements and behavior of the floor systems during...... detailing of these integrally cast deck panels and to modify them by providing individually cast anchor points in the precast ECC slab, which are subsequently used to attach a steel truss substructure.Full-scale experiments were carried out to verify the structural behavior of the integrally cast panels...

  9. Seasonal variations of radon concentrations in single-family houses with different sub-structures

    DEFF Research Database (Denmark)

    Majborn, B.

    1992-01-01

    Seasonal variations of indoor radon concentrations have been studied in 70 single-family houses selected according to the type of sub-structure and the type of soil underneath the house. Five categories of sub-structure were included - slab-on-grade, crawl space, basement, and combinations...... of basement with slab-on-grade or crawl space. Half of the houses are located on clayey till and the other half on glaciofluvial gravel. In each house radon was measured in a living room and a bedroom, in the basement if present, and in the crawl space if present and accessible. The measurements were made...... with track detectors on a quarterly basis throughout a year. For living rooms and bedrooms the seasonal variations range from being highly significant for the slab-on-grade houses to being insignificant for the crawl space houses. For basements and crawl spaces the geometric mean radon concentrations do...

  10. Damage detection test of a substructure model of the National Swimming Center

    Institute of Scientific and Technical Information of China (English)

    QIAN JiaRu; JI XiaoDong; ZHANG WeiJing; XU LongHe; FU XueYi; GU Lei

    2008-01-01

    In order to detect the damage locations of complex spatial structures,a sensor region-based damage detection approach was developed based on the damage locating vectors method.A normalized damage locating index was introduced to identify the damage regions.An experiment on damage detection of a substructure model of the National Swimming Center 'Water Cube' was carried out.Two damage patterns were involved in the experiment.The test model was excited by using hammer impacts.Acceleration responses of the undamaged and damaged struc-ture model were measured.Modal parameters were identified from the acceleration responses by utilizing the eigensystem realization algorithm (ERA).By using the developed sensor region-based method,the damage regions of the substructure model were located.The results show that the proposed method is able to effec-tively locate the damage regions.

  11. Thinking outside the ROCs: Designing Decorrelated Taggers (DDT) for jet substructure

    Science.gov (United States)

    Dolen, James; Harris, Philip; Marzani, Simone; Rappoccio, Salvatore; Tran, Nhan

    2016-05-01

    We explore the scale-dependence and correlations of jet substructure observables to improve upon existing techniques in the identification of highly Lorentz-boosted objects. Modified observables are designed to remove correlations from existing theoretically well-understood observables, providing practical advantages for experimental measurements and searches for new phenomena. We study such observables in W jet tagging and provide recommendations for observables based on considerations beyond signal and background efficiencies.

  12. Thinking outside the ROCs: Designing Decorrelated Taggers (DDT) for jet substructure

    CERN Document Server

    Dolen, James; Marzani, Simone; Rappoccio, Salvatore; Tran, Nhan

    2016-01-01

    We explore the scale-dependence and correlations of jet substructure observables to improve upon existing techniques in the identification of highly Lorentz-boosted objects. Modified observables are designed to remove correlations from existing theoretically well-understood observables, providing practical advantages for experimental measurements and searches for new phenomena. We study such observables in $W$ jet tagging and provide recommendations for observables based on considerations beyond signal and background efficiencies.

  13. A dynamic model with substructures for contact-impact analysis of flexible multibody systems

    Institute of Scientific and Technical Information of China (English)

    GUO; Anping(郭安萍); HONG; Jiazhen(洪嘉振); YANG; Hui(杨辉)

    2003-01-01

    Using a substructure synthesis method this paper studies the longitudinal compressive impact of a flexible bar with a rigid body. The crucial variable affecting the validity of the method is derived theoretically. By computational simulation tests, excellent agreement has been found between the solution of this model and the exact solution when the variable is chosen suitably. Considering both the computational efficiency and the accuracy of solutions obtained on the model in different engineering problems, several optimum values of the variable are suggested.

  14. Pre-Processing and Re-Weighting Jet Images with Different Substructure Variables

    CERN Document Server

    Huynh, Lynn

    2016-01-01

    This work is an extension of Monte Carlo simulation based studies in tagging boosted, hadronically decaying W bosons at a center of mass energy of s = 13 TeV. Two pre-processing techniques used with jet images, translation and rotation, are first examined. The generated jet images for W signal jets and QCD background jets are then rescaled and weighted with five different substructure variables for visual comparison.

  15. Detection of Lensing Substructure Using ALMA Observations of the Dusty Galaxy SDP.81

    Science.gov (United States)

    Hezaveh, Yashar D.; Dalal, Neal; Marrone, Daniel P.; Mao, Yao-Yuan; Morningstar, Warren; Wen, Di; Blandford, Roger D.; Carlstrom, John E.; Fassnacht, Christopher D.; Holder, Gilbert P.; Kemball, Athol; Marshall, Philip J.; Murray, Norman; Perreault Levasseur, Laurence; Vieira, Joaquin D.; Wechsler, Risa H.

    2016-05-01

    We study the abundance of substructure in the matter density near galaxies using ALMA Science Verification observations of the strong lensing system SDP.81. We present a method to measure the abundance of subhalos around galaxies using interferometric observations of gravitational lenses. Using simulated ALMA observations we explore the effects of various systematics, including antenna phase errors and source priors, and show how such errors may be measured or marginalized. We apply our formalism to ALMA observations of SDP.81. We find evidence for the presence of a M = 108.96±0.12 M ⊙ subhalo near one of the images, with a significance of 6.9σ in a joint fit to data from bands 6 and 7; the effect of the subhalo is also detected in both bands individually. We also derive constraints on the abundance of dark matter (DM) subhalos down to M ˜ 2 × 107 M ⊙, pushing down to the mass regime of the smallest detected satellites in the Local Group, where there are significant discrepancies between the observed population of luminous galaxies and predicted DM subhalos. We find hints of additional substructure, warranting further study using the full SDP.81 data set (including, for example, the spectroscopic imaging of the lensed carbon monoxide emission). We compare the results of this search to the predictions of ΛCDM halos, and find that given current uncertainties in the host halo properties of SDP.81, our measurements of substructure are consistent with theoretical expectations. Observations of larger samples of gravitational lenses with ALMA should be able to improve the constraints on the abundance of galactic substructure.

  16. Aligned Carbon Nanotube Reinforcement of Aerospace Carbon Fiber Composites: Substructural Strength Evaluation for Aerostructure Applications

    OpenAIRE

    Guzman de Villoria, Roberto; Ydrefors, L.; Hallander, P.; Ishiguro, Kyoko; Nordin, P.; Wardle, Brian L.

    2012-01-01

    Vertically aligned carbon nanotubes (VACNTs) are placed between all plies in an aerospace carbon fiber reinforced plastic laminate (unidirectional plies, [(0/90/±45)2]s) to reinforce the interlaminar region in the z-direction. Significant improvement in Mode I and II interlaminar toughness have been observed previously. In this work, several substructural in-plane strength tests relevant to aerostructures were undertaken: bolt/tension-bearing, open hole compression, and L-shape laminate be...

  17. Substructures developed during creep and cyclic tests of type 304 stainless steel (heat 9T2796)

    Energy Technology Data Exchange (ETDEWEB)

    Swindeman, R.W.; Bhargava, R.K.; Sikka, V.K.; Moteff, J.

    1977-09-01

    Substructures developed in tested specimens of a reference heat of type 304 stainless steel (heat 9T2796) are examined. Data include dislocation densities, cell and subgrain sizes, and carbide precipitate sizes. Testing conditions range for temperatures from 482 to 649/sup 0/C, for stresses from 28 to 241 MPa, and for times from 4 to 15,000 hr. As expected, it is observed that temperature, stress, and time have strong influences on substructure. The change in the dislocation density is too small to measure for conditions which produce less than 1 percent monotonic strain. No cells form, and the major alteration of substructure is the precipitation of M/sub 23/C/sub 6/ carbides on grain boundaries, on twin boundaries, and on some dislocations. At stresses ranging from 69 to 172 MPa and at temperatures ranging from 482 to 593/sup 0/C, the dislocation density increases with increasing stress and is generally higher than expected from studies made at higher temperatures. Dislocations are arranged in fine networks stabilized by carbides. At stresses above 172 MPa and temperatures to 649/sup 0/C, the dislocation density is too great to measure. Cells develop which are finer in size than cells developed at similar stresses but at higher temperatures. Dislocation densities and cell sizes for cyclic specimens are comparable to data for creep-tested specimens. On the basis of the observed substructures, recommendations are made regarding further studies which would assist in the development of constitutive equations for high-temperature inelastic analysis of reactor components.

  18. Analysis of East Asia genetic substructure using genome-wide SNP arrays.

    Directory of Open Access Journals (Sweden)

    Chao Tian

    Full Text Available Accounting for population genetic substructure is important in reducing type 1 errors in genetic studies of complex disease. As efforts to understand complex genetic disease are expanded to different continental populations the understanding of genetic substructure within these continents will be useful in design and execution of association tests. In this study, population differentiation (Fst and Principal Components Analyses (PCA are examined using >200 K genotypes from multiple populations of East Asian ancestry. The population groups included those from the Human Genome Diversity Panel [Cambodian, Yi, Daur, Mongolian, Lahu, Dai, Hezhen, Miaozu, Naxi, Oroqen, She, Tu, Tujia, Naxi, Xibo, and Yakut], HapMap [ Han Chinese (CHB and Japanese (JPT], and East Asian or East Asian American subjects of Vietnamese, Korean, Filipino and Chinese ancestry. Paired Fst (Wei and Cockerham showed close relationships between CHB and several large East Asian population groups (CHB/Korean, 0.0019; CHB/JPT, 00651; CHB/Vietnamese, 0.0065 with larger separation with Filipino (CHB/Filipino, 0.014. Low levels of differentiation were also observed between Dai and Vietnamese (0.0045 and between Vietnamese and Cambodian (0.0062. Similarly, small Fst's were observed among different presumed Han Chinese populations originating in different regions of mainland of China and Taiwan (Fst's <0.0025 with CHB. For PCA, the first two PC's showed a pattern of relationships that closely followed the geographic distribution of the different East Asian populations. PCA showed substructure both between different East Asian groups and within the Han Chinese population. These studies have also identified a subset of East Asian substructure ancestry informative markers (EASTASAIMS that may be useful for future complex genetic disease association studies in reducing type 1 errors and in identifying homogeneous groups that may increase the power of such studies.

  19. AFM friction and adhesion mapping of the substructures of human hair cuticles

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James R., E-mail: james.smith@port.ac.uk [School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael' s Building, White Swan Road, Portsmouth, PO1 2DT (United Kingdom); Tsibouklis, John; Nevell, Thomas G. [School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael' s Building, White Swan Road, Portsmouth, PO1 2DT (United Kingdom); Breakspear, Steven [School of Pharmacy and Biomedical Sciences, University of Portsmouth, St Michael' s Building, White Swan Road, Portsmouth, PO1 2DT (United Kingdom); Global R and D–Hair Beauty Laboratory, Kao Corporation, 2-1-3, Bunka Sumida-ku, Tokyo, 131-8501 (Japan)

    2013-11-15

    Using atomic force microscopy, values of the microscale friction coefficient, the tip (silicon nitride) - surface adhesion force and the corresponding adhesion energy, for the substructures that constitute the surface of human hair (European brown hair) have been determined from Amonton plots. The values, mapped for comparison with surface topography, corresponded qualitatively with the substructures’ plane surface characteristics. Localised maps and values of the frictional coefficient, extracted avoiding scale edge effects, are likely to inform the formulation of hair-care products and treatments.

  20. Substructuring preconditioners for an h-p domain decomposition method with interior penalty mortaring

    KAUST Repository

    Antonietti, P. F.

    2014-05-13

    We propose and study an iterative substructuring method for an h-p Nitsche-type discretization, following the original approach introduced in Bramble et al. Math. Comp. 47(175):103–134, (1986) for conforming methods. We prove quasi-optimality with respect to the mesh size and the polynomial degree for the proposed preconditioner. Numerical experiments assess the performance of the preconditioner and verify the theory. © 2014, Springer-Verlag Italia.

  1. Substructure Analysis of Selected Low Richness 2dFGRS Clusters of Galaxies

    CERN Document Server

    Burgett, W S; Davis, D S; Colless, M; De Propris, R; Baldry, I K; Baugh, C; Bland-Hawthorn, J; Bridges, T J; Cannon, R; Cole, S; Collins, C; Couch, W; Cross, N; Dalton, G B; Driver, S; Efstathiou, G P; Ellis, R; Frenk, C; Glazebrook, K; Hawkins, E; Jackson, C; Lahav, O; Lewis, I; Lumsden, S; Maddox, S; Madgwick, D; Norberg, P; Peacock, J A; Percival, W; Peterson, B; Sutherland, W; Taylor, K; Burgett, William S.; Vick, Michael M.; Davis, David S.; Colless, Matthew; Propris, Roberto De; Baldry, Ivan; Baugh, Carlton; Bland-Hawthorn, Joss; Bridges, Terry; Cannon, Russell; Cole, Shaun; Collins, Chris; Couch, Warrick; Cross, Nicholas; Dalton, Gavin; Driver, Simon; Efstathiou, George; Ellis, Richard; Frenk, Carlos; Glazebrook, Karl; Hawkins, Edward; Jackson, Carole; Lahav, Ofer; Lewis, Ian; Lumsden, Stuart; Maddox, Steve; Madgwick, Darren; Norberg, Peder; Peacock, John A.; Percival, Will; Peterson, Bruce; Sutherland, Will; Taylor, Keith

    2004-01-01

    Complementary one-, two-, and three-dimensional tests for detecting the presence of substructure in clusters of galaxies are applied to recently obtained data from the 2dF Galaxy Redshift Survey. The sample of 25 clusters used in this study includes 16 clusters not previously investigated for substructure. Substructure is detected at or greater than the 99% CL level in at least one test for 21 of the 25 clusters studied here. From the results, it appears that low richness clusters commonly contain subclusters participating in mergers. About half of the clusters have two or more components within 0.5 h^{-1} Mpc of the cluster centroid, and at least three clusters (Abell 1139, Abell 1663, and Abell S333) exhibit velocity-position characteristics consistent with the presence of possible cluster rotation, shear, or infall dynamics. The geometry of certain features is consistent with influence by the host supercluster environments. In general, our results support the hypothesis that low richness clusters relax to ...

  2. Dynamic substructure model for multiple impact responses of micro/nano piezoelectric precision drive system

    Institute of Scientific and Technical Information of China (English)

    SHEN YuNian; YIN XiaoChun

    2009-01-01

    A dynamic substructure technique which considers the electromechanlcal coupling effect of the PZT and the inertial effect of flexible components is presented to study the multiple impact dynamic be-havior of micro/nano piezoelectric impact drive systems. It can investigate the step-like motion of ob-ject body and the multiple impacts behaviors reasonably by the comparison of the experimental data and the numerical solution of the spring-mass model. It is expected to have higher accuracy in the numerical simulations of the motion and the responses, especially to high frequency pulse voltage excitations. The present dynamic substructure technique has firstly studied reasonably the propaga-tions of piezoelectric-induced transient waves and impact-induced transient waves. It is helpful to the failure analysis and the design of piezoelectric stack and flexible components. The present dynamic substructure technique can be applied to the transient dynamics optimization design and the precision control of the micro/nano piezoelectric impact drive systems.

  3. Major Substructure in the M31 Outer Halo: the East Cloud

    CERN Document Server

    McMonigal, B; Conn, A R; Mackey, A D; Lewis, G F; Irwin, M J; Martin, N F; McConnachie, A W; Ferguson, A M N; Ibata, R A; Huxor, A P

    2015-01-01

    We present the first detailed analysis of the East Cloud, a highly disrupted diffuse stellar substructure in the outer halo of M31. The core of the substructure lies at a projected distance of $\\sim100$ kpc from the centre of M31 in the outer halo, with possible extensions reaching right into the inner halo. Using Pan-Andromeda Archaeological Survey photometry of red giant branch stars, we measure the distance, metallicity and brightness of the cloud. Using Hubble Space Telescope data, we independently measure the distance and metallicity to the two globular clusters coincident with the East Cloud core, PA-57 and PA-58, and find their distances to be consistent with the cloud. Four further globular clusters coincident with the substructure extensions are identified as potentially associated. Combining the analyses, we determine a distance to the cloud of $814^{+20}_{-9}$ kpc, a metallicity of $[Fe/H] = -1.2\\pm0.1$, and a brightness of $M_V = -10.7\\pm0.4$ mag. Even allowing for the inclusion of the potential e...

  4. Automatic identification of mobile and rigid substructures in molecular dynamics simulations and fractional structural fluctuation analysis.

    Directory of Open Access Journals (Sweden)

    Leandro Martínez

    Full Text Available The analysis of structural mobility in molecular dynamics plays a key role in data interpretation, particularly in the simulation of biomolecules. The most common mobility measures computed from simulations are the Root Mean Square Deviation (RMSD and Root Mean Square Fluctuations (RMSF of the structures. These are computed after the alignment of atomic coordinates in each trajectory step to a reference structure. This rigid-body alignment is not robust, in the sense that if a small portion of the structure is highly mobile, the RMSD and RMSF increase for all atoms, resulting possibly in poor quantification of the structural fluctuations and, often, to overlooking important fluctuations associated to biological function. The motivation of this work is to provide a robust measure of structural mobility that is practical, and easy to interpret. We propose a Low-Order-Value-Optimization (LOVO strategy for the robust alignment of the least mobile substructures in a simulation. These substructures are automatically identified by the method. The algorithm consists of the iterative superposition of the fraction of structure displaying the smallest displacements. Therefore, the least mobile substructures are identified, providing a clearer picture of the overall structural fluctuations. Examples are given to illustrate the interpretative advantages of this strategy. The software for performing the alignments was named MDLovoFit and it is available as free-software at: http://leandro.iqm.unicamp.br/mdlovofit.

  5. A hybrid system identification methodology for wireless structural health monitoring systems based on dynamic substructuring

    Science.gov (United States)

    Dragos, Kosmas; Smarsly, Kay

    2016-04-01

    System identification has been employed in numerous structural health monitoring (SHM) applications. Traditional system identification methods usually rely on centralized processing of structural response data to extract information on structural parameters. However, in wireless SHM systems the centralized processing of structural response data introduces a significant communication bottleneck. Exploiting the merits of decentralization and on-board processing power of wireless SHM systems, many system identification methods have been successfully implemented in wireless sensor networks. While several system identification approaches for wireless SHM systems have been proposed, little attention has been paid to obtaining information on the physical parameters (e.g. stiffness, damping) of the monitored structure. This paper presents a hybrid system identification methodology suitable for wireless sensor networks based on the principles of component mode synthesis (dynamic substructuring). A numerical model of the monitored structure is embedded into the wireless sensor nodes in a distributed manner, i.e. the entire model is segmented into sub-models, each embedded into one sensor node corresponding to the substructure the sensor node is assigned to. The parameters of each sub-model are estimated by extracting local mode shapes and by applying the equations of the Craig-Bampton method on dynamic substructuring. The proposed methodology is validated in a laboratory test conducted on a four-story frame structure to demonstrate the ability of the methodology to yield accurate estimates of stiffness parameters. Finally, the test results are discussed and an outlook on future research directions is provided.

  6. Dynamic substructure model for multiple impact responses of micro/nano piezoelectric precision drive system

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A dynamic substructure technique which considers the electromechanical coupling effect of the PZT and the inertial effect of flexible components is presented to study the multiple impact dynamic be- havior of micro/nano piezoelectric impact drive systems. It can investigate the step-like motion of ob- ject body and the multiple impacts behaviors reasonably by the comparison of the experimental data and the numerical solution of the spring-mass model. It is expected to have higher accuracy in the numerical simulations of the motion and the responses, especially to high frequency pulse voltage excitations. The present dynamic substructure technique has firstly studied reasonably the propaga- tions of piezoelectric-induced transient waves and impact-induced transient waves. It is helpful to the failure analysis and the design of piezoelectric stack and flexible components. The present dynamic substructure technique can be applied to the transient dynamics optimization design and the precision control of the micro/nano piezoelectric impact drive systems.

  7. Indirect Inverse Substructuring Method for Multibody Product Transport System with Rigid and Flexible Coupling

    Directory of Open Access Journals (Sweden)

    Jun Wang

    2015-01-01

    Full Text Available The aim of this paper is to develop a new frequency response function- (FRF- based indirect inverse substructuring method without measuring system-level FRFs in the coupling DOFs for the analysis of the dynamic characteristics of a three-substructure coupled product transport system with rigid and flexible coupling. By enforcing the dynamic equilibrium conditions at the coupling coordinates and the displacement compatibility conditions, a closed-form analytical solution to inverse substructuring analysis of multisubstructure coupled product transport system is derived based on the relationship of easy-to-monitor component-level FRFs and the system-level FRFs at the coupling coordinates. The proposed method is validated by a lumped mass-spring-damper model, and the predicted coupling dynamic stiffness is compared with the direct computation, showing exact agreement. The method developed offers an approach to predict the unknown coupling dynamic stiffness from measured FRFs purely. The suggested method may help to obtain the main controlling factors and contributions from the various structure-borne paths for product transport system.

  8. Atomic force microscopic observation on substructure of pollen exine in Cedrus deodara and Metasequoia glyptostroboides

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The substructure of pollen exine in Cedrus deodara (Roxb.) Loud. and Metasequoia glyptostroboides Hu et Cheng has been examined with an atomic force microscope (AFM). The results indicate that the exine substructure units containing sporopollenin in two species are similar in shape, which are granular, but slightly different in size. In Cedrus the substructure unit of pollen exine appears to be 56-99 nm long and 42-74 nm wide, while in Metasequoia it appears to be 81-118 nm long and 43-98 nm wide. It has been observed that the subunits of pollen exine in Cedrus arranged tightly to form short-rod-like or spheroidal pollen exine units, several or more than ten of which formed an island-like structure. There are various spaces among these island-like structures which are interconnected to occupy the entire pollen exine. In Metasequoia, the subunits of pollen exine also arranged tightly with a distribution tendency of cluster of 3-10, however, no obvious boundary exists among these clusters. From our results, it is concluded that there is no tendency of helical arrangement for the subunits of pollen exine in Cedrus and Metasequoia, and the results support Southworth' view that subunits of pollen exine are granular shape in lattice structure.

  9. Calibration of TDR Test Probe for Measuring Moisture in the Body of the Railway Substructure and its Subgrade

    Directory of Open Access Journals (Sweden)

    Dobeš Peter

    2015-12-01

    Full Text Available In the introduction of the paper there is characterized a way of monitoring the moisture in the railway substructure in the experimental stand, which is a part of the experimental workplace of the Department of Railway Engineering and Track Management. A substantial part of the paper is devoted to the calibration of TDR test probe for selected rock materials as a basic prerequisite for the determination of the actual moisture in the body of the railway substructure and subgrade.

  10. The aesthetic composite bridge.

    Science.gov (United States)

    Feinman, R A

    1997-01-01

    New developments are constantly introduced in the search for the optimal treatment modality to restore a single anterior tooth. The patient attention has shifted to aesthetics of the restoration, biocompatibility of the dental materials utilized, conservative preparation of the teeth to be restored, and the retention of intact adjacent dentition. The learning objective of this article is to review the methods currently utilized and to present a recently introduced treatment modality--the two-component bridge, which combines the strength and resiliency of composite resin with the aesthetic advantages of porcelain. The technology of the material is reviewed, the predominantly lingual tooth preparation procedures are outlined, and the bridge try-in is described. The advantages of the two-component bridge are presented along with the contraindications and suggestions of careful case selection. Three cases with congenitally missing maxillary lateral incisors in youthful patients are presented to supplement the theoretical outline and to describe and illustrate the clinical procedure.

  11. Istanbul Bridge Conference 2014

    CERN Document Server

    Gülkan, Polat; Mahmoud, Khaled

    2016-01-01

      The book includes peer-reviewed contributions selected from presentations given at the Istanbul Bridge Conference 2014, held from August 11 – 13 in Istanbul, Turkey. It reports on the current challenges in bridge engineering faced by professionals around the globe, giving a special emphasis to recently developed techniques, innovations and opportunities. The book covers key topics in the field, including modeling and analysis methods; construction and erection techniques; design for extreme events and condition assessment and structural health monitoring. There is a balanced presentation of theory, research and practice. This book, which provides the readers with a comprehensive and timely reference guide on current practices in bridge engineering, is intended for professionals, academic researchers and students alike.

  12. Active Control of Suspension Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper some recent research on active control of very long suspension bridges, is presented. The presentation is based on research work at Aalborg University, Denmark. The active control system is based on movable flaps attached to the bridge girder. Wind load on bridges with or without...... flaps attached to the girder is briefly presented. A simple active control system is discussed. Results from wind tunnel experiments with a bridge section show that flaps can be used effectively to control bridge girder vibrations. Flutter conditions for suspension bridges with and without flaps...

  13. Indian practice on estimation of scour around bridge piers—A comment

    Indian Academy of Sciences (India)

    Umesh C Kothyari

    2007-06-01

    Well-laid foundation is mostly provided in road and railway bridges in India over large and medium-sized rivers. The age-old Lacey–Inglis method is used for estimation of the design scour depth around bridge elements such as pier, abutment, guide bank, spur and groyene. Codal provisions are seen to produce too large a scour depth around bridge elements resulting in bridge sub-structures that lead to increased construction costs. Limitations that exist in the codes of practice are illustrated in this paper using examples. The methods recently developed for estimation of the scour are described. New railway and road bridges are required to be built in large numbers in the near future across several rivers to strengthen such infrastructure in the country. It is strongly felt that provisions in the existing codes of practice for determination of design scour depth require immediate review. The present paper provides a critical note on the practices followed in India for estimating the design scour depth.

  14. BUILDING "BRIDGES" WITH QUALITY ASSURANCE

    Science.gov (United States)

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

  15. Existing Steel Railway Bridges Evaluation

    Science.gov (United States)

    Vičan, Josef; Gocál, Jozef; Odrobiňák, Jaroslav; Koteš, Peter

    2016-12-01

    The article describes general principles and basis of evaluation of existing railway bridges based on the concept of load-carrying capacity determination. Compared to the design of a new bridge, the modified reliability level for existing bridges evaluation should be considered due to implementation of the additional data related to bridge condition and behaviour obtained from regular inspections. Based on those data respecting the bridge remaining lifetime, a modification of partial safety factors for actions and materials could be respected in the bridge evaluation process. A great attention is also paid to the specific problems of determination of load-caring capacity of steel railway bridges in service. Recommendation for global analysis and methodology for existing steel bridge superstructure load-carrying capacity determination are described too.

  16. Comparison of two models for bridge-assisted charge transfer

    CERN Document Server

    Schreiber, M; Kleinekathöfer, U

    1999-01-01

    Based on the reduced density matrix method, we compare two different approaches to calculate the dynamics of the electron transfer in systems with donor, bridge, and acceptor. In the first approach a vibrational substructure is taken into account for each electronic state and the corresponding states are displaced along a common reaction coordinate. In the second approach it is assumed that vibrational relaxation is much faster than the electron transfer and therefore the states are modeled by electronic levels only. In both approaches the system is coupled to a bath of harmonic oscillators but the way of relaxation is quite different. The theory is applied to the electron transfer in ${\\rm H_2P}-{\\rm ZnP}-{\\rm Q}$ with free-base porphyrin (${\\rm H_2P}$) being the donor, zinc porphyrin (${\\rm ZnP}$) being the bridge and quinone (${\\rm Q}$) the acceptor. The parameters are chosen as similar as possible for both approaches and the quality of the agreement is discussed.

  17. DOE Information Bridge

    CERN Document Server

    United States. Department of Energy. Office of Scientific and Technical Information

    DOE Information Bridge, a component of EnergyFiles, provides free, convenient, and quick access to full-text DOE research and development reports in physics, chemistry, materials, biology, environmental sciences, energy technologies, engineering, computer and information science, renewable energy, and other topics. This vast collection includes over 43,000 reports that have been received and processed by OSTI since January 1995.

  18. Bridging the Technological Gap.

    Science.gov (United States)

    Lazow, Robert; And Others

    The aim of "Bridging the Technological Gap" (BTG), a federally funded demonstration project, is to use microcomputer technology in the rehabilitation of the psychiatrically disabled. Through the use of a custom designed microcomputer software package, clients receive remediation in areas of specific cognitive and behavioral deficits. The project…

  19. Bridging a Cultural Gap

    Science.gov (United States)

    Leviatan, Talma

    2008-01-01

    There has been a broad wave of change in tertiary calculus courses in the past decade. However, the much-needed change in tertiary pre-calculus programmes--aimed at bridging the gap between high-school mathematics and tertiary mathematics--is happening at a far slower pace. Following a discussion on the nature of the gap and the objectives of a…

  20. Bridge over troubled water?

    DEFF Research Database (Denmark)

    Svendsen, Gunnar Lind Haase; Nannestad, Peter; Svendsen, Gert Tinggaard

    2008-01-01

    The problem of integrating non-Western immigrants into Western welfare states is the focus of this paper. To address this issue, we suggest a social capital approach in which we apply the conceptual pair of bridging social capital (BR), which connects an individual to the broader social structure...

  1. Building a Straw Bridge

    Science.gov (United States)

    Teaching Science, 2015

    2015-01-01

    This project is for a team of students (groups of two or three are ideal) to design and construct a model of a single-span bridge, using plastic drinking straws as the building material. All steps of the design, construction, testing and critiquing stages should be recorded by students in a journal. Students may like to include labelled diagrams,…

  2. Building Bridges to China.

    Science.gov (United States)

    Wasta, Stephanie; Scott, Margaret

    1998-01-01

    Describes a theme cycle called "Building Bridges to China" developed for third grade students that focuses on the similarities between the lives of children and families in China and the United States. Explains that the theme cycle addresses the National Geography Standards and three of the National Council for the Social Studies standards. (CMK)

  3. The Bridges of Taishun County

    Institute of Scientific and Technical Information of China (English)

    MaJianhe

    2003-01-01

    The American film The Bridges of Madison County captured the imagination of many Chinese moviegoers with its bittersweet love story and scenes of rustic covered bridges. But the U.S. can't lay sole claim to such spectacular rural sights:China has its own county worldrenowned for unforgettable bridges.

  4. Revised Rules for Concrete Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Jensen, F. M.; Middleton, C.;

    This paper is based on research performed for the Highway Agency, London, UK under the project DPU/9/44 "Revision of Bridge Assessment Rules Based on Whole Life Performance: Concrete Bridges" It contains details of a methodology which can be used to generate Whole Life (WL) reliability profiles....... These WL reliability profiles may be used to establish revised rules for Concrete Bridges....

  5. Dynamic Bridge Response for a Bridge-friendly Truck

    Directory of Open Access Journals (Sweden)

    V. Šmilauer

    2004-01-01

    Full Text Available A truck with controlled semi-active suspensions traversing a bridge is examined for benefits to the bridge structure. The original concept of a road-friendly truck was extended to a bridge-friendly vehicle, using the same optimization tools. A half-car model with two independently driven axles is coupled with simply supported bridges (beam, slab model with the span range from 5 m to 50 m. Surface profile of the bridge deck is either stochastic or in the shape of a bump or a pot in the mid-span. Numerical integration in the MATLAB/SIMULINK environment solves coupled dynamic equations of motion with optimized truck suspensions. The rear axle generates the prevailing load and to a great extent determines the bridge response. A significant decrease in contact road-tire forces is observed and the mid-span bridge deflections are on average smaller, when compared to commercial passive suspensions. 

  6. Simulation of multivariate diffusion bridges

    DEFF Research Database (Denmark)

    Bladt, Mogens; Finch, Samuel; Sørensen, Michael

    We propose simple methods for multivariate diffusion bridge simulation, which plays a fundamental role in simulation-based likelihood and Bayesian inference for stochastic differential equations. By a novel application of classical coupling methods, the new approach generalizes a previously...... proposed simulation method for one-dimensional bridges to the mulit-variate setting. First a method of simulating approzimate, but often very accurate, diffusion bridges is proposed. These approximate bridges are used as proposal for easily implementable MCMC algorithms that produce exact diffusion bridges...

  7. Study of Jet Substructure in the ATLAS Experiment using Distributed Analysis within Spanish Tier-2 infrastructures

    OpenAIRE

    Oliver García, Elena

    2013-01-01

    Study of Jet Substructure in the ATLAS experiment using Distributed Analysis within Spanish Tier-2 Infrastructures (Estudio de Subestructura de Jets en el experimento ATLAS usando Análisis Distribuido dentro de las Infraestructuras del Tier-2 Español) Resumen en español 1. Motivación En el Large Hadron Collider (LHC) se producen partículas consideradas objetos ‘boosted’ donde sus productos de desintegración se concentran en una pequeña parte del detector. El estudio de estos ...

  8. Cold Dark Matter Substructure and Galactic Disks I: Morphological Signatures of Hierarchical SatelliteAccretion

    Energy Technology Data Exchange (ETDEWEB)

    Kazantzidis, Stelios; Bullock, James S.; Zentner, Andrew R.; Kravtsov, Andrey V.; Moustakas, Leonidas A.

    2007-12-03

    We conduct a series of high-resolution, fully self-consistent dissipation less N-body simulations to investigate the cumulative effect of substructure mergers onto thin disk galaxies in the context of the {Lambda}CDM paradigm of structure formation. Our simulation campaign is based on a hybrid approach combining cosmological simulations and controlled numerical experiments. Substructure mass functions, orbital distributions, internal structures, and accretion times are culled directly from cosmological simulations of galaxy-sized cold dark matter (CDM) halos. We demonstrate that accretions of massive subhalos onto the central regions of host halos, where the galactic disk resides, since z {approx} 1 should be common occurrences. In contrast, extremely few satellites in present-day CDM halos are likely to have a significant impact on the disk structure. This is due to the fact that massive subhalos with small orbital pericenters that are most capable of strongly perturbing the disk become either tidally disrupted or suffer substantial mass loss prior to z = 0. One host halo merger history is subsequently used to seed controlled N-body experiments of repeated satellite impacts on an initially-thin Milky Way-type disk galaxy. These simulations track the effects of six dark matter substructures, with initial masses in the range {approx} (0.7-2) x 10{sup 10} M{sub {circle_dot}} ({approx} 20-60% of the disk mass), crossing the disk in the past {approx} 8 Gyr. We show that these accretion events produce several distinctive observational signatures in the stellar disk including: a long-lived, low-surface brightness, ring-like feature in the outskirts; a significant flare; a central bar; and faint filamentary structures that (spuriously) resemble tidal streams in configuration space. The final distribution of disk stars exhibits a complex vertical structure that is well-described by a standard 'thin-thick' disk decomposition, where the 'thick' disk

  9. Chemical composition of stars in kinematical substructures of the galactic disk

    Directory of Open Access Journals (Sweden)

    Gorbaneva T.I.

    2012-02-01

    Full Text Available The Y, Zr, La, Ce, Nd , Sm and Eu abundances were found in LTE approach, and the abundance of Ba was computed in NLTE approximation for 280 FGK dwarfs in the region of metallicity of − 1<[Fe]< + 0.3. The selection of stars belonging to thin and thick disks and the stream Hercules was made on kinematic criteria. The analysis of enrichment of the different substructures of the Galaxy with α-element (Mg, Si, the iron peak (Ni and neutron-capture elements was carried out.

  10. Assessment of dynamic substructuring of a wind turbine foundation applicable for aeroelastic simulations

    DEFF Research Database (Denmark)

    Damgaard, Mads; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

    2015-01-01

    Dynamic vibration response of a wind turbine structure is examined. Emphasis is put on the dynamic interaction between the foundation and the subsoil, since stiffness and energy dissipation of the substructure affect the dynamic response of the wind turbine. Based on a standard lumped......-parameter model fitted to the frequency response of the ground, a surface foundation is implemented into the aeroelastic code FLEX5. In case of a horizontal stratum overlaying a homogeneous half-space and within the low frequency range, analyses show that a standard lumped-parametermodel provides an accurate...

  11. An early neutrino experiment: how we missed quark substructure in 1963

    Science.gov (United States)

    Perkins, D. H.

    2013-12-01

    Some 50 years after the event seems to be an appropriate time at which to take a long look back at one of the early neutrino experiments at CERN. This report is principally about a failure in a 1963 bubble chamber experiment to detect substructure in the nucleon, a year before the quark concept was invented by Gell-Mann and Zweig, and some five years before the existence of quarks as real dynamical objects was definitely established in deep inelastic electron scattering experiments at Stanford.

  12. Structure and substructure analysis of DAFT/FADA galaxy clusters in the [0.4-0.9] redshift range

    CERN Document Server

    Guennou, L; Durret, F; Neto, G B Lima; Ulmer, M P; Clowe, D; LeBrun, V; Martinet, N; Allam, S; Annis, J; Basa, S; Benoist, C; Biviano, A; Cappi, A; Cypriano, E S; Gavazzi, R; Halliday, C; Ilbert, O; Jullo, E; Just, D; Limousin, M; Márquez, I; Mazure, A; Murphy, K J; Plana, H; Rostagni, F; Russeil, D; Schirmer, M; Slezak, E; Tucker, D; Zaritsky, D; Ziegler, B

    2013-01-01

    We analyse the structures of all the clusters in the DAFT/FADA survey for which XMM-Newton and/or a sufficient number of galaxy redshifts in the cluster range is available, with the aim of detecting substructures and evidence for merging events. These properties are discussed in the framework of standard cold dark matter cosmology.XMM-Newton data were available for 32 clusters, for which we derive the X-ray luminosity and a global X-ray temperature for 25 of them. For 23 clusters we were able to fit the X-ray emissivity with a beta-model and subtract it to detect substructures in the X-ray gas. A dynamical analysis based on the SG method was applied to the clusters having at least 15 spectroscopic galaxy redshifts in the cluster range: 18 X-ray clusters and 11 clusters with no X-ray data. Only major substructures will be detected. Ten substructures were detected both in X-rays and by the SG method. Most of the substructures detected both in X-rays and with the SG method are probably at their first cluster per...

  13. Bridging Classroom Language Ethnography

    OpenAIRE

    GRENFELL, MICHAEL JAMES

    2012-01-01

    PUBLISHED Paper #5: Bridging Classroom Language Ethnography, New Literacy Studies and Bourdieu?s Social Philosophy: Principles and Practice The purpose of this paper is to analyze and synthesize the various ways that classroom language ethnography, NLS, and Bourdieu?s social philosophy, were integrated. The goal of the analysis and synthesis is to provide a fresh perspective and fruitful insights on literacy in all its manifestations that provides the foundations for a more robust...

  14. Bridging as Coercive Accommodation

    CERN Document Server

    Bos, J W; Mineur, A M; Bos, Johan; Buitelaar, Paul; Mineur, Anne-Marie

    1995-01-01

    In this paper we discuss the notion of "bridging" in Discourse Representation Theory as a tool to account for discourse referents that have only been established implicitly, through the lexical semantics of other referents. In doing so, we use ideas from Generative Lexicon theory, to introduce antecedents for anaphoric expressions that cannot be "linked" to a proper antecedent, but that do not need to be "accommodated" because they have some connection to the network of discourse referents that is already established.

  15. Relationship among wear-resistance of three-body abrasion,substructure and property in martensite steels

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The effects of subsurface hardness on wear-resistance of martensitic steel 20Cr, 40CrSi, 60Mn, T8 and T10 in three-body abrasion under static load was investigated. It shows that the characteristic ofthe subsurface hardness distribution and the abrasive wear resistanceis related to the substructure near the worn surface. The substructure of the tested martensite steel has an apparent relationship with thecarbon content and steels with moderate carbon content and hardness exhibit good resistance to abrasive wear. The competition of the work-hardening effect and the temper softening effect, which resulted from deformation and friction heat generating during abrasive wear is considered to be a main reason for the relation among wear-resistance, hardness and substructure. At the test conditions, the wear-resistance of 40CrSi is the best.

  16. Development of a High-fidelity Experimental Substructure Test Rig for Grid-scored Sandwich Panels in Wind Turbine Blades

    DEFF Research Database (Denmark)

    Laustsen, Steffen; Lund, Erik; Kühlmeier, L.;

    2014-01-01

    This paper outlines high-fidelity experimental substructure testing of sandwich panels which constitute the aerodynamic outer shell of modern wind turbine blades. A full-scale structural experimental and numerical characterisation of a composite wind turbine blade has been conducted. The developm...... of substructure tests for composite wind turbine blades. Furthermore, recommendations on the use of grid-scored sandwich structures in wind turbine blades are presented, which outline the sensitivity in terms of quasi-static strength to the established loading conditions.......This paper outlines high-fidelity experimental substructure testing of sandwich panels which constitute the aerodynamic outer shell of modern wind turbine blades. A full-scale structural experimental and numerical characterisation of a composite wind turbine blade has been conducted...

  17. How well can cold-dark-matter substructures account for the observed radio flux-ratio anomalies?

    CERN Document Server

    Xu, Dandan; Gao, Liang; Wang, Jie; Frenk, Carlos; Mao, Shude; Schneider, Peter; Springel, Volker

    2014-01-01

    Discrepancies between the observed and model-predicted radio flux ratios are seen in a number of quadruply-lensed quasars. The most favored interpretation of these anomalies is that CDM substructures present in lensing galaxies perturb the lens potentials and alter image magnifications and thus flux ratios. So far no consensus has emerged regarding whether or not the predicted CDM substructure abundance fully accounts for the lensing flux anomaly observations. Accurate modeling relies on a realistic lens sample in terms of both the lens environment and internal structures and substructures. In this paper we construct samples of generalised and specific lens potentials, to which we add (rescaled) subhalo populations from the galaxy-scale Aquarius and the cluster-scale Phoenix simulation suites. We further investigate the lensing effects from subhalos of masses several orders of magnitude below the simulation resolution limit. The resulting flux ratio distributions are compared to the currently best available s...

  18. A Synoptic Map of Halo Substructures from the Pan-STARRS1 3\\pi\\ Survey

    CERN Document Server

    Bernard, Edouard J; Schlafly, Edward F; Martin, Nicolas F; Rix, Hans-Walter; Bell, Eric F; Finkbeiner, Douglas P; Goldman, Bertrand; Martinez-Delgado, David; Sesar, Branimir; Wyse, Rosemary F G; Burgett, William S; Chambers, Kenneth C; Draper, Peter W; Hodapp, Klaus W; Kudritzki, Rolf-Peter; Magnier, Eugene A; Metcalfe, Nigel; Wainscoat, Richard J; Waters, Christopher

    2016-01-01

    We present a panoramic map of the entire Milky Way halo north of dec~-30 degrees (~30,000 deg^2), constructed by applying the matched-filter technique to the Pan-STARRS1 3Pi Survey dataset. Using single-epoch photometry reaching to g~22, we are sensitive to stellar substructures with heliocentric distances between 3.5 and ~35 kpc. We recover almost all previously-reported streams in this volume and demonstrate that several of these are significantly more extended than earlier datasets have indicated. In addition, we also report five new candidate stellar streams. One of these features appears significantly broader and more luminous than the others and is likely the remnant of a dwarf galaxy. The other four streams are consistent with a globular cluster origin, and three of these are rather short in projection (<10 degrees), suggesting that streams like Ophiuchus may not be that rare. Finally, a significant number of more marginal substructures are also revealed by our analysis; many of these features can a...

  19. Mexican mestizo population sub-structure: effects on genetic and forensic statistical parameters.

    Science.gov (United States)

    Noris, Gino; Santana, Carla; Meraz-Ríos, Marco Antonio; de Lourdes Munoz, María; Majluf-Cruz, Abraham; Magaña, Jonathan J; Granados, Julio; Quezada, Rosa; Revilla, María Cristina; Martínez-Salas, Sergio; Xihuitl, Salvador; Martínez de la Escalera, Gonzalo; Díaz-Badillo, Alvaro; Calderon-Aranda, Emma S; Gómez, Rocío

    2012-12-01

    Since Mexican mestizos are an admixed population, it is necessary to determine the effects that the substructure of the population has on genetic and forensic parameters. With this aim, a study was performed with 15 STR loci (CODIS plus D2S1338 and D19S433) on 1,640 unrelated Mexican mestizos. We determine allele and genotypic frequencies observing departure from Hardy-Weinberg expectation (12 out of 15 loci, with an excess of homozygotes, Fis > 0), as well as pairs of loci in an apparent linkage disequilibrium (13 of 92 loci). We conducted a test for genetic population stratification, the results show that the Mexican mestizo population is substructured into three subgroups, which are in HW and linkage equilibrium. The combination of the 15 loci in the whole population has high forensic efficiency with the capacity to genetically discriminate one individual in one quintillion (1/10(18)). Our data potentially validates the use of these 15 STR loci to establish forensic identity and parentage testing for legal purposes, and offers a powerful tool for genetic variation analysis. However, given that the population is stratified, we highly recommend applying a correction with the inbreeding coefficient in calculations of paternity and forensic studies to avoid erroneous assumptions.

  20. CLUMPY: Jeans analysis, $\\gamma$-ray and neutrino fluxes from dark matter (sub-)structures

    CERN Document Server

    Bonnivard, Vincent; Nezri, Emmanuel; Charbonnier, Aldée; Combet, Céline; Maurin, David

    2015-01-01

    We present an update of the CLUMPY code for the calculation of the astrophysical J-factors (from dark matter annihilation/decay) for any Galactic or extragalactic dark matter halo including substructures: the concentration-mass relationship may now be drawn from a distribution, boost factors can include several levels of substructures, and triaxiality is a new option for dark matter haloes. This new version takes advantage of the cfitsio and HEALPix libraries to propose FITS output maps using the HEALPix pixelisation scheme. Skymaps for $\\gamma$-ray and neutrino signals from generic annihilation/decay spectra are now direct outputs of CLUMPY. Smoothing by a user-defined instrumental Gaussian beam is also possible. In addition to these improvements, the main novelty is the implementation of a Jeans analysis module, to obtain dark matter density profiles from kinematic data in relaxed spherical systems (e.g., dwarf spheroidal galaxies). The code is also interfaced with the GreAT toolkit designed for Markov Chai...

  1. Statistics and implications of substructure detected in a representative sample of X-ray clusters

    CERN Document Server

    Chon, Gayoung; Smith, Graham

    2012-01-01

    We present a morphological study of 35 X-ray luminous galaxy clusters at 0.15Substructure Survey (LoCuSS), for which deep XMM-Newton observations are available. We characterise the structure of the X-ray surface brightness distribution of each cluster by measuring both their power ratios and centroid shift, and thus rank the clusters by the degree of substructure. These complementary probes give a consistent description of the cluster morphologies with some well understood exceptions. We find a remarkably tight correlation of regular morphology with the occurrence of cool cores in clusters. We also compare our measurements of X-ray morphology with measurements of the luminosity gap statistics and ellipticity of the brightest cluster galaxy (BCG). We check how our new X-ray morphological analysis maps onto cluster scaling relations, finding that (i) clusters with relatively undisturbed X-ray morphologies are on average more luminous at fixed X-ray...

  2. Probing the evolution of the substructure frequency in galaxy clusters up to z~1

    CERN Document Server

    Weißmann, A; Chon, G

    2013-01-01

    Context. Galaxy clusters are the last and largest objects to form in the standard hierarchical structure formation scenario through merging of smaller systems. The substructure frequency in the past and present epoch provides excellent means for studying the underlying cosmological model. Aims. Using X-ray observations, we study the substructure frequency as a function of redshift by quantifying and comparing the fraction of dynamically young clusters at different redshifts up to z=1.08. We are especially interested in possible biases due to the inconsistent data quality of the low-z and high-z samples. Methods. Two well-studied morphology estimators, power ratio P3/P0 and center shift w, were used to quantify the dynamical state of 129 galaxy clusters, taking into account the different observational depth and noise levels of the observations. Results. Owing to the sensitivity of P3/P0 to Poisson noise, it is essential to use datasets with similar photon statistics when studying the P3/P0-z relation. We degra...

  3. A Synoptic Map of Halo Substructures from the Pan-STARRS1 3π Survey

    Science.gov (United States)

    Bernard, Edouard J.; Ferguson, Annette M. N.; Schlafly, Edward F.; Martin, Nicolas F.; Rix, Hans-Walter; Bell, Eric F.; Finkbeiner, Douglas P.; Goldman, Bertrand; Martínez-Delgado, David; Sesar, Branimir; Wyse, Rosemary F. G.; Burgett, William S.; Chambers, Kenneth C.; Draper, Peter W.; Hodapp, Klaus W.; Kaiser, Nicholas; Kudritzki, Rolf-Peter; Magnier, Eugene A.; Metcalfe, Nigel; Wainscoat, Richard J.; Waters, Christopher

    2016-08-01

    We present a panoramic map of the entire Milky Way halo north of δ ˜ -30° (˜ 30,000 deg2), constructed by applying the matched-filter technique to the Pan-STARRS1 3π Survey dataset. Using single-epoch photometry reaching to g ˜22, we are sensitive to stellar substructures with heliocentric distances between 3.5 and ˜35 kpc. We recover almost all previously-reported streams in this volume and demonstrate that several of these are significantly more extended than earlier datasets have indicated. In addition, we also report five new candidate stellar streams. One of these features appears significantly broader and more luminous than the others and is likely the remnant of a dwarf galaxy. The other four streams are consistent with a globular cluster origin, and three of these are rather short in projection (≲ 10°), suggesting that streams like Ophiuchus may not be that rare. Finally, a significant number of more marginal substructures are also revealed by our analysis; many of these features can also be discerned in matched-filter maps produced by other authors from SDSS data, and hence they are very likely to be genuine. However, the extant 3π data is currently too shallow to determine their properties or produce convincing CMDs. The global view of the Milky Way provided by Pan-STARRS1 provides further evidence for the important role of both globular cluster disruption and dwarf galaxy accretion in building the Milky Way's stellar halo.

  4. Gamma-rays from dark matter annihilations strongly constrain the substructure in halos

    CERN Document Server

    Pinzke, Anders; Bergstrom, Lars

    2009-01-01

    Recently, it has been shown that electrons and positrons from dark matter (DM) annihilations provide an excellent fit to the Fermi, PAMELA, and HESS data. Using this DM model, which requires an enhancement of the annihilation cross section over its standard value to match the observations, we show that it immediately implies an observable level of gamma-ray emission for the Fermi telescope from nearby galaxy clusters such as Virgo and Fornax. We show that this DM model implies a peculiar feature from final state radiation that is a distinctive signature of DM. Using the EGRET upper limit on the gamma-ray emission from Virgo, we constrain the minimum mass of substructures within DM halos to be > 0.1 M_sol - five orders of magnitudes larger than the expectation for cold dark matter. This limits the cutoff scale in the linear matter power spectrum to k 10^4 M_sol: if the true substructure cutoff is much smaller than this, the DM interpretation of the Fermi/PAMELA/HESS data must be wrong. To address the problem ...

  5. Constraining dark matter sub-structure with the dynamics of astrophysical systems

    CERN Document Server

    Gonzalez-Morales, Alma X; Aguilar, Luis A

    2012-01-01

    The accuracy of the measurements of some astrophysical dynamical systems allows to constrain the existence of incredibly small gravitational perturbations. In particular, the internal Solar System dynamics (planets, Earth-Moon) opens up the possibility, for the first time, to prove the abundance, mass and size, of dark sub-structures at the Earth vicinity. We find that adopting the standard dark matter density, its local distribution can be composed by sub-solar mass halos with no currently measurable dynamical consequences, regardless of the mini-halo fraction. On the other hand, it is possible to exclude the presence of dark streams with linear mass densities higher than $\\lambda_{\\rm st}> 10^{-10} \\Msun/\\AU$ (about the Earth mass spread along the diameter of the SS up to the Kuiper belt). In addition, we review the dynamics of wide binaries inside the dwarf spheroidal galaxies in the MW. The dynamics of such kind of binaries seem to be compatible with the presence of a huge fraction of dark sub-structure, ...

  6. Substructure dependence of jet cross sections at HERA and determination of $\\alpha_{s}$

    CERN Document Server

    Chekanov, S; Abt, I; Adamczyk, L; Adamus, M; Adler, V; Aghuzumtsyan, G; Antonioli, P; Antonov, A; Arneodo, M; Bailey, D S; Bamberger, A; Barakbaev, A N; Barbagli, G; Barbi, M; Bari, G; Barreiro, F; Bartsch, D; Basile, M; Behrens, U; Bellagamba, L; Bellan, P M; Benen, A; Bertolin, A; Bhadra, S; Bloch, I; Bold, T; Boos, E G; Borras, K; Boscherini, D; Brock, I; Brook, N H; Brugnera, R; Brümmer, N; Bruni, A; Bruni, G; Bussey, P J; Butterworth, J M; Büttner, C; Bylsma, B; Caldwell, A; Capua, M; Cara Romeo, G; Carli, T; Carlin, R; Catterall, C D; Chiochia, V; Chwastowski, J; Ciborowski, J; Ciesielski, R; Cifarelli, Luisa; Cindolo, F; Cloth, P; Cole, J E; Collins-Tooth, C; Contin, A; Cooper-Sarkar, A M; Coppola, N; Cormack, C; Corradi, M; Corriveau, F; Costa, M; Cottrell, A; D'Agostini, Giulio; Dal Corso, F; Danilov, P; Dannheim, D; De Pasquale, S; Dementiev, R K; Derrick, M; Devenish, R C E; Dhawan, S; Dobur, D; Dolgoshein, B A; Doyle, A T; Drews, G; Durkin, L S; Dusini, S; Eisenberg, Y; Ermolov, P F; Eskreys, Andrzej; Everett, A; Ferrando, J; Ferrero, M I; Figiel, J; Filges, D; Foster, B; Foudas, C; Fourletov, S; Fourletova, J; Fricke, U; Fusayasu, T; Gabareen, A; Galas, A; Gallo, E; Garfagnini, A; Geiser, A; Genta, C; Gialas, I; Giusti, P; Gladilin, L K; Gladkov, D; Glasman, C; Gliga, S; Goers, S; Goncalo, R; González, O; Gosau, T; Göttlicher, P; Grabowska-Bold, I; Grigorescu, G; Grijpink, S; Grzelak, G; Gutsche, O; Gwenlan, C; Haas, T; Hain, W; Hall-Wilton, R; Hamatsu, R; Hamilton, J; Hanlon, S; Hart, J C; Hartmann, H; Hartner, G; Heaphy, E A; Heath, G P; Helbich, M; Heusch, C A; Hilger, E; Hillert, S; Hirose, T; Hochman, D; Holm, U; Horn, C; Iacobucci, G; Iga, Y; Inuzuka, M; Irrgang, P; Jakob, H P; Jones, T W; Kagawa, S; Kahle, B; Kaji, H; Kananov, S; Karshon, M; Karstens, F; Kataoka, M; Katkov, I I; Kcira, D; Keramidas, A; Khein, L A; Kim, J Y; Kind, O; Kisielewska, D; Kitamura, S; Koffeman, E; Kohno, T; Kooijman, P; Koop, T; Korzhavina, I A; Kotanski, A; Kötz, U; Kowal, A M; Kowal, M; Kowalski, H; Kramberger, G; Kreisel, A; Krumnack, N; Kuze, M; Kuzmin, V A; Labarga, L; Labes, H; Lainesse, J; Lammers, S; Lelas, D; Levchenko, B B; Levy, A; Li, L; Lightwood, M S; Lim, H; Lim, I T; Limentani, S; Ling, T Y; Liu, X; Löhr, B; Lohrmann, E; Loizides, J H; Long, K R; Longhin, A; Lukina, O Yu; Luzniak, P; Ma, K J; Maddox, E; Magill, S; Mankel, R; Margotti, A; Marini, G; Martin, J F; Mastroberardino, A; Matsuzawa, K; Mattingly, M C K; McCubbin, N A; Melzer-Pellmann, I A; Menary, S R; Metlica, F; Meyer, U; Miglioranzi, S; Milite, M; Mirea, A; Monaco, V; Montanari, A; Musgrave, B; Nagano, K; Namsoo, T; Nania, R; Nguyen, C N; Nigro, A; Ning, Y; Notz, D; Nowak, R J; Nuncio, A E; Oh, B Y; Olkiewicz, K; Pac, M Y; Padhi, S; Palmonari, F; Parenti, A; Park, I H; Patel, S; Paul, E; Pavel, Usan; Pawlak, J M; Pelfer, P G; Pellegrino, A; Pesci, A; Piotrzkowski, K; Plucinsky, P P; Pokrovskiy, N S; Polini, A; Posocco, M; Proskuryakov, A S; Przybycien, M B; Rautenberg, J; Raval, A; Reeder, D D; Ren, Z; Renner, R; Repond, J; Rinaldi, L; Riveline, U; Robins, S; Rosin, M; Ruspa, M; Ryan, P; Sacchi, R; Salehi, H; Sartorelli, G; Savin, A A; Saxon, D H; Schagen, S; Schioppa, M; Schlenstedt, S; Schleper, P; Schmidke, W B; Schneekloth, U; Schörner-Sadenius, T; Sciulli, F; Shcheglova, L M; Skillicorn, I O; Slominski, W; Smith, W H; Soares, M; Solano, A; Son, D; Sosnovtsev, V V; Stairs, D G; Stanco, L; Standage, J; Stifutkin, A; Stonjek, S; Stopa, P; Stösslein, U; Straub, P B; Suchkov, S; Susinno, G; Suszycki, L; Sutiak, J; Sutton, M R; Sztuk, J; Szuba, D; Szuba, J; Tandler, J; Tapper, A D; Targett-Adams, C; Tassi, E; Tawara, T; Terron, J; Tiecke, H G; Tokushuku, K; Tsurugai, T; Turcato, M; Tymieniecka, T; Ukleja, A; Ukleja, J; Vázquez, M; Vlasov, N N; Voss, K C; Walczak, R; Walsh, R; Wang, M; Whitmore, J J; Wichmann, K; Wick, K; Wiggers, L; Wills, H H; Wing, M; Wolf, G; Yamada, S; Yamashita, T; Yamazaki, Y; Yoshida, R; Youngman, C; Zambrana, M; Zawiejski, L; Zeuner, W; Zhautykov, B O; Zichichi, A; Ziegler, A; Zotkin, S A; De Favereau, J; De Wolf, E; Del Peso, J

    2004-01-01

    Jet substructure and differential cross sections for jets produced in the photoproduction and deep inelastic ep scattering regimes have been measured with the ZEUS detector at HERA using an integrated luminosity of 82.2 pb-1. The substructure of jets has been studied in terms of the jet shape and subjet multiplicity for jets with transverse energies Et(jet) > 17 GeV. The data are well described by the QCD calculations. The jet shape and subjet multiplicity are used to tag gluon- and quark-initiated jets. Jet cross sections as functions of Et(jet), jet pseudorapidity, the jet-jet scattering angle, dijet invariant mass and the fraction of the photon energy carried by the dijet system are presented for gluon- and quark-tagged jets. The data exhibit the behaviour expected from the underlying parton dynamics. A value of alphas(Mz) of alphas(Mz) = 0.1176 +-0.0009(stat.) -0.0026 +0.0009 (exp.) -0.0072 +0.0091 (th.) was extracted from the measurements of jet shapes in deep inelastic scattering.

  7. Effects of Dark Matter Substructures on Gravitational Lensing: Results from the Aquarius Simulations

    CERN Document Server

    Xu, D D; Wang, J; Springel, V; Gao, L; White, S D M; Frenk, C S; Jenkins, A; Li, G; Navarro, J F

    2009-01-01

    We use high-resolution Aquarius simulations of Milky Way-sized haloes in the LCDM cosmology to study the effects of dark matter substructures on gravitational lensing. Each halo is resolved with ~ 10^8 particles (at a mass resolution ~ 10^3-4 M_sun/h) within its virial radius. Subhaloes with masses larger than 10^5 M_sun/h are well resolved, an improvement of at least two orders of magnitude over previous lensing studies. We incorporate a baryonic component modelled as a Hernquist profile and account for the response of the dark matter via adiabatic contraction. We focus on the "anomalous" flux ratio problem, in particular on the violation of the cusp-caustic relation due to substructures. We find that subhaloes with masses less than ~ 10^8 M_sun/h play an important role in causing flux anomalies; such low mass subhaloes have been unresolved in previous studies. There is large scatter in the predicted flux ratios between different haloes and between different projections of the same halo. In some cases, the f...

  8. The Extraordinary Amount of Substructure in the Hubble Frontier Fields Cluster Abell 2744

    CERN Document Server

    Jauzac, M; Schwinn, J; Harvey, D; Baugh, C M; Robertson, A; Bose, S; Massey, R; Owers, M; Ebeling, H; Shan, H Y; Jullo, E; Kneib, J -P; Richard, J; Atek, H; Clément, B; Egami, E; Israel, H; Knowles, K; Limousin, M; Natarajan, P; Rexroth, M; Taylor, P; Tchernin, C

    2016-01-01

    We present a joint optical/X-ray analysis of the massive galaxy cluster Abell 2744 (z=0.308). Our strong- and weak-lensing analysis within the central region of the cluster, i.e., at R<1Mpc from the brightest cluster galaxy, reveals eight substructures, including the main core. All of these dark-matter halos are detected with a significance of at least 5sigma and feature masses ranging from 0.5 to 1.4x10^{14}Msun within R<150kpc. Merten et al. (2011) and Medezinski et al. (2016) substructures are also detected by us. We measure a slightly higher mass for the main core component than reported previously and attribute the discrepancy to the inclusion of our tightly constrained strong-lensing mass model built on Hubble Frontier Fields data. X-ray data obtained by XMM-Newton reveal four remnant cores, one of them a new detection, and three shocks. Unlike Merten et al. (2011), we find all cores to have both dark and luminous counterparts. A comparison with clusters of similar mass in the MXXL simulations yie...

  9. The Substructure of the Solar Corona Observed in the Hi-C Telescope

    Science.gov (United States)

    Winebarger, A.; Cirtain, J.; Golub, L.; DeLuca, E.; Savage, S.; Alexander, C.; Schuler, T.

    2014-01-01

    In the summer of 2012, the High-resolution Coronal Imager (Hi-C) flew aboard a NASA sounding rocket and collected the highest spatial resolution images ever obtained of the solar corona. One of the goals of the Hi-C flight was to characterize the substructure of the solar corona. We therefore calculate how the intensity scales from a low-resolution (AIA) pixels to high-resolution (Hi-C) pixels for both the dynamic events and "background" emission (meaning, the steady emission over the 5 minutes of data acquisition time). We find there is no evidence of substructure in the background corona; the intensity scales smoothly from low-resolution to high-resolution Hi-C pixels. In transient events, however, the intensity observed with Hi-C is, on average, 2.6 times larger than observed with AIA. This increase in intensity suggests that AIA is not resolving these events. This result suggests a finely structured dynamic corona embedded in a smoothly varying background.

  10. Statistics of Dark Matter Substructure: III. Halo-to-Halo Variance

    CERN Document Server

    Jiang, Fangzhou

    2016-01-01

    We present a study of unprecedented statistical power regarding the halo-to-halo variance of dark matter substructure. Using a combination of N-body simulations and a semi-analytical model, we investigate the variance in subhalo mass fractions and subhalo occupation numbers, with an emphasis on how these statistics scale with halo formation time. We demonstrate that the subhalo mass fraction, f_sub, is mainly a function of halo formation time, with earlier forming haloes having less substructure. At fixed formation redshift, the average f_sub is virtually independent of halo mass, and the mass dependence of f_sub is therefore mainly a manifestation of more massive haloes assembling later. We compare observational constraints on f_sub from gravitational lensing to our model predictions and simulation results. Although the inferred f_sub are substantially higher than the median LCDM predictions, they fall within the 95th percentile due to halo-to-halo variance. We show that while the halo occupation distributio...

  11. Motion and deformation estimation from medical imagery by modeling sub-structure interaction and constraints

    KAUST Repository

    Sundaramoorthi, Ganesh

    2012-09-13

    This paper presents a novel medical image registration algorithm that explicitly models the physical constraints imposed by objects or sub-structures of objects that have differing material composition and border each other, which is the case in most medical registration applications. Typical medical image registration algorithms ignore these constraints and therefore are not physically viable, and to incorporate these constraints would require prior segmentation of the image into regions of differing material composition, which is a difficult problem in itself. We present a mathematical model and algorithm for incorporating these physical constraints into registration / motion and deformation estimation that does not require a segmentation of different material regions. Our algorithm is a joint estimation of different material regions and the motion/deformation within these regions. Therefore, the segmentation of different material regions is automatically provided in addition to the image registration satisfying the physical constraints. The algorithm identifies differing material regions (sub-structures or objects) as regions where the deformation has different characteristics. We demonstrate the effectiveness of our method on the analysis of cardiac MRI which includes the detection of the left ventricle boundary and its deformation. The experimental results indicate the potential of the algorithm as an assistant tool for the quantitative analysis of cardiac functions in the diagnosis of heart disease.

  12. Dynamic Analysis of Jacket Substructure for Offshore Wind Turbine Generators under Extreme Environmental Conditions

    Directory of Open Access Journals (Sweden)

    Wen-Jeng Lai

    2016-10-01

    Full Text Available In order to develop dynamic analysis technologies regarding the design of offshore wind turbine generators (OWTGs, a special project called Offshore Code Comparison Collaboration Continuation (OC4 was conducted by IEA (International Energy Agency in 2010. A similar project named INER-OC4 has been performed by the Institute of Nuclear Energy Research (INER to develop the OWTG technologies of Taiwan. Since the jacket substructure will be applied to Taiwan OWTGs before 2020, the INER-OC4 project has been devoted to the design and analysis of jacket support structure. In this work, the preliminary result of INER-OC4 is presented. A simplified analysis procedure for jacket support structure has been proposed. Both of the NREL (National Renewable Energy Laboratory 5 MW OWTG FAST model and OC4 jacket substructure model have been built and analyzed under severe design load cases (DLCs of IEC (International Electrotechnical commission 61400-3. Simulation results of six severe DLCs are performed in this work and the results are in agreement with the requirements of API (American Petroleum Institute and NORSOK (Norwegian Petroleum Industry standards.

  13. RINGED SUBSTRUCTURE AND A GAP AT 1 au IN THE NEAREST PROTOPLANETARY DISK

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, Sean M.; Wilner, David J.; Bai, Xue-Ning; Öberg, Karin I.; Ricci, Luca [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Zhu, Zhaohuan [Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Peyton Hall, Princeton, NJ 08544 (United States); Birnstiel, Tilman [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Carpenter, John M. [Joint ALMA Observatory (JAO), Alonso de Cordova 3107, Vitacura-Santiago de Chile (Chile); Pérez, Laura M. [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany); Hughes, A. Meredith [Department of Astronomy, Wesleyan University, Van Vleck Observatory, 96 Foss Hill Drive, Middletown, CT 06457 (United States); Isella, Andrea, E-mail: sandrews@cfa.harvard.edu [Department of Physics and Astronomy, Rice University, 6100 Main Street, Houston, TX 77005 (United States)

    2016-04-01

    We present long baseline Atacama Large Millimeter/submillimeter Array (ALMA) observations of the 870 μm continuum emission from the nearest gas-rich protoplanetary disk, around TW Hya, that trace millimeter-sized particles down to spatial scales as small as 1 au (20 mas). These data reveal a series of concentric ring-shaped substructures in the form of bright zones and narrow dark annuli (1–6 au) with modest contrasts (5%–30%). We associate these features with concentrations of solids that have had their inward radial drift slowed or stopped, presumably at local gas pressure maxima. No significant non-axisymmetric structures are detected. Some of the observed features occur near temperatures that may be associated with the condensation fronts of major volatile species, but the relatively small brightness contrasts may also be a consequence of magnetized disk evolution (the so-called zonal flows). Other features, particularly a narrow dark annulus located only 1 au from the star, could indicate interactions between the disk and young planets. These data signal that ordered substructures on ∼au scales can be common, fundamental factors in disk evolution and that high-resolution microwave imaging can help characterize them during the epoch of planet formation.

  14. The investigation of dynamic behaviour of a structure using wave-based substructuring method

    Directory of Open Access Journals (Sweden)

    Ahmad Basri Ahmad Burhani

    2017-01-01

    Full Text Available There is an increasing need for accurate, efficient and economical methods for the investigation of the dynamic behaviour of large complex structures within the engineering community. The component mode synthesis (CMS has been perceived by the community to be an attractive efficient method for the investigation. However, the method has substantial shortcomings, particularly in analysing a structure having a large number of interface degrees of freedom (DOFs between substructures. This paper puts forward a method, based upon the wave-based substructuring (WBS for the investigation of the dynamic behaviour of a structure with a large number of interface DOFs. The finite element method is used to construct the full finite element model of the structure and NASTRAN 103 is used for the normal modes analysis. A new finite element model of the structure with reduced interface DOFs is constructed based on the WBS. The measurement of the dynamic behaviour of the structure is carried out using free-free boundary conditions and an impact hammer test. The predicted results of the proposed method are then compared with those from the full finite element model and experimental counterparts. The accuracy and efficiency of the proposed method are discussed and illustrated with two different case studies.

  15. Development and design of a semi-floater substructure for multi-megawatt wind turbines at 50+ m water depths

    DEFF Research Database (Denmark)

    NJOMO WANDJI, Wilfried; Natarajan, Anand; Dimitrov, Nikolay Krasimirov

    2016-01-01

    A semi-floater concept as a substructure for multi-megawatt wind turbines is developed herein for installation at 50þ m water depths. The semi-floater concept is a hybrid between a fixed monopile type support structure and a floating spar buoy. The configuration of the substructure is composed...... turbine components, and to exhibit low platform displacement at the mean sea level. Finally, the overall performance of the structure related to energy production is similar to that of a reference wind turbine situated on land....

  16. Vulnerability of bridges to fire

    DEFF Research Database (Denmark)

    Giuliani, Luisa; Crosti, C.; Gentili, F.

    2012-01-01

    Even if recent effort in developing methodology and measures for design structures against fire and explosions has been mostly focused on buildings, bridges can also be very sensitive to those actions, as witnesses by some recent bridge accidents, which caused major economic losses and also...... endangered people safety in few cases. Purpose of this paper is making a focus on the state of the art of the research and current regulations concerning the response of bridges to fire. Several cases of bridge fires are reported and a focus is made on the occurrence and consequence of bridge fires......, considering both the costs deriving by structural damages and by limited serviceability and other indirect societal aspects. Few cases of recent bridge fire are reviewed in detail and structural consequences are highlighted, distinguishing between damages directly induced by fire and damages induced by local...

  17. Morphological aspects of myocardial bridges.

    Science.gov (United States)

    Lujinović, Almira; Kulenović, Amela; Kapur, Eldan; Gojak, Refet

    2013-11-01

    Although some myocardial bridges can be asymptomatic, their presence often causes coronary disease either through direct compression of the "tunnel" segment or through stimulation and accelerated development of atherosclerosis in the segment proximally to the myocardial bridge. The studied material contained 30 human hearts received from the Department of Anatomy. The hearts were preserved 3 to 5 days in 10% formalin solution. Thereafter, the fatty tissue was removed and arterial blood vessels prepared by careful dissection with special reference to the presence of the myocardial bridges. Length and thickness of the bridges were measured by the precise electronic caliper. The angle between the myocardial bridge fibre axis and other axis of the crossed blood vessel was measured by a goniometer. The presence of the bridges was confirmed in 53.33% of the researched material, most frequently (43.33%) above the anterior interventricular branch. The mean length of the bridges was 14.64 ± 9.03 mm and the mean thickness was 1.23 ± 1.32 mm. Myocardial bridge fibres pass over the descending blood vessel at the angle of 10-90 degrees. The results obtained on a limited sample suggest that the muscular index of myocardial bridge is the highest for bridges located on RIA, but that the difference is not significant in relation to bridges located on other branches. The results obtained suggest that bridges located on other branches, not only those on RIA, could have a great contractive power and, consequently, a great compressive force, which would be exerted on the wall of a crossed blood vessel.

  18. Modular FRP Composite Bridge Deck

    OpenAIRE

    ECT Team, Purdue

    2007-01-01

    The bridge infrastructure of the United States is in constant need of repair and rehabilitation. It is reported that 43% of the bridges in the USA have been identified as being structurally deficient or functionally obsolete due to corrosion. SuperdeckTM, a non-corrosive fiber reinforced polymer (FRP) composite bridge deck. The Deck is designed and engineered into a lightweight, strong and rigid structure that will not corrode. The deck sections, composed of hexagon and double-trapezoid profi...

  19. Modelling railway bridge asset management

    OpenAIRE

    Le, Bryant Linh Hai

    2014-01-01

    The UK has a long history in the railway industry with a large number of railway assets. Railway bridges form one of the major asset groups with more than 35,000 bridges. The majority of the bridge population are old being constructed over 100 years ago. Many of the bridges were not designed to meet the current network demand. With an expected increasing rate of deterioration due to the increasing traffic loads and intensities, the management authorities are faced with the difficult task of k...

  20. Dynamic responses of cable-stayed bridges to vehicular loading including the effects of the local vibration of cables

    Institute of Scientific and Technical Information of China (English)

    He ZHANG; Xu XIE

    2011-01-01

    Stay cables,the primary load carrying components of cable-stayed bridges (CSBs),are characterised by high flexibility which increases with the span of the bridge.This makes stay cables vulnerable to local vibrations which may have significant effects on the dynamic responses of long-span CSBs.Hence,it is essential to account for these effects in the assessment of the dynamics CSBs.In this paper,the dynamic responses of CSBs under vehicular loads are studied using the finite element method (FEM),while the local vibration of stay cables is analyzed using the substructure method.A case study of a cable-stayed steel bridge with a center span of 448 m demonstrates that stay cables undergo large displacements in the primary mode of the whole bridge although,in general,a cable's local vibrations are not obvious.The road surface roughness has significant effects on the interaction force between the deck and vehicle but little effect on the global response of the bridge.Load impact factors of the main girder and tower are small,and the impact factors of the tension of cables are larger than those of the displacements of girders and towers.

  1. GAGA: A New Algorithm for Genomic Inference of Geographic Ancestry Reveals Fine Level Population Substructure in Europeans

    NARCIS (Netherlands)

    O. Lao Grueso (Oscar); F. Liu (Fan); A. Wollstein (Andreas); M.H. Kayser (Manfred)

    2014-01-01

    textabstractAttempts to detect genetic population substructure in humans are troubled by the fact that the vast majority of the total amount of observed genetic variation is present within populations rather than between populations. Here we introduce a new algorithm for transforming a genetic dista

  2. The structure and early evolution of massive star forming regions - Substructure in the infrared dark cloud SDC13

    CERN Document Server

    McGuire, Catherine; Peretto, Nicolas; Zhang, Qizhou; Traficante, Alessio; Avison, Adam; Jimenez-Serra, Izaskun

    2016-01-01

    Investigations into the substructure of massive star forming regions are essential for understanding the observed relationships between core mass distributions and mass distributions in stellar clusters, differentiating between proposed mechanisms of massive star formation. We study the substructure in the two largest fragments (i.e. cores) MM1 and MM2, in the infrared dark cloud complex SDC13. As MM1 appears to be in a later stage of evolution than MM2, comparing their substructure provides an insight in to the early evolution of massive clumps. We report the results of high resolution SMA dust continuum observations towards MM1 and MM2. Combining these data with Herschel observations, we carry out RADMC-3D radiative transfer modelling to characterise the observed substructure. SMA continuum data indicates 4 sub-fragments in the SDC13 region. The nature of the second brightest sub-fragment (B) is uncertain as it does not appear as prominent at the lower MAMBO resolution or at radio wavelengths. Statistical a...

  3. Reheating Effects in the Matter Power Spectrum and Implications for Substructure

    CERN Document Server

    Erickcek, Adrienne L

    2011-01-01

    The thermal and expansion history of the Universe before big bang nucleosynthesis is unknown. We investigate the evolution of cosmological perturbations through the transition from an early matter era to radiation domination. We treat reheating as the perturbative decay of an oscillating scalar field into relativistic plasma and cold dark matter. After reheating, we find that subhorizon perturbations in the decay-produced dark matter density are significantly enhanced, while subhorizon radiation perturbations are instead suppressed. If dark matter originates in the radiation bath after reheating, this suppression may be the primary cut-off in the matter power spectrum. Conversely, for dark matter produced non-thermally from scalar decay, enhanced perturbations can drive structure formation during the cosmic dark ages and dramatically increase the abundance of compact substructures. For low reheat temperatures, we find that as much as 50% of all dark matter is in microhalos with M > 0.1 Earth masses at z=100, ...

  4. The SLUGGS Survey: Globular cluster system kinematics and substructure in NGC 4365

    CERN Document Server

    Blom, Christina; Brodie, Jean P; Foster, Caroline; Romanowsky, Aaron J; Spitler, Lee R; Strader, Jay

    2012-01-01

    We present a kinematic analysis of the globular cluster (GC) system of the giant elliptical galaxy NGC 4365 and find several distinct kinematic substructures. This analysis is carried out using radial velocities for 269 GCs, obtained with the DEIMOS instrument on the Keck II telescope as part of the SAGES Legacy Unifying Globulars and Galaxies Survey (SLUGGS). We find that each of the three (formerly identified) GC colour subpopulations reveal distinct rotation properties. The rotation of the green GC subpopulation is consistent with the bulk of NGC 4365's stellar light, which `rolls' about the photometric major axis. The blue and red GC subpopulations show `normal' rotation about the minor axis. We also find that the red GC subpopulation is rotationally dominated beyond 2.5 arcmin (~17 kpc) and that the root mean squared velocity of the green subpopulation declines sharply with radius suggesting a possible bias towards radial orbits relative to the other GC subpopulations. Additionally, we find a population ...

  5. Hints of Thermal Fragmentation in the Primordial Substructure of NGC2264

    Science.gov (United States)

    Teixeira, P. S.; Lada, C. J.; Young, E. T.; Marengo, M.; Muench, A.; Muzerolle, J.; Siegler, N.; Rieke, G.; Hartmann, L.; Megeath, T.; Fazio, G.

    2005-12-01

    We present Spitzer observations of a young star forming region within NGC2264. These observations reveal new 24 micron sources in curious linear alignments, extending radially like spokes on a wheel from a previously known luminous young protostar. These 24 micron sources are found to be mostly ( ˜60%) Class I protostars that are highly embedded within dense filamentary molecular material. The protostars still retain the primordial substructuring of the parental cloud. We find the protostars to be separated by regular intervals that are consistent with the Jeans length for the average density of the associated molecular material, suggesting that thermal fragmentation played an important role during the star forming process in this region. The figure shows a false color image of this young region built from MIPS 24 micron (red), IRAC 8 micron (green), and IRAC 3.6 micron (blue) data. PT acknowledges support from the scholarship SFRH/BD/13984/2003 FCT, Portugal.

  6. Accounting for ancestry: population substructure and genome-wide association studies.

    Science.gov (United States)

    Tian, Chao; Gregersen, Peter K; Seldin, Michael F

    2008-10-15

    Accounting for the genetic substructure of human populations has become a major practical issue for studying complex genetic disorders. Allele frequency differences among ethnic groups and subgroups and admixture between different ethnic groups can result in frequent false-positive results or reduced power in genetic studies. Here, we review the problems and progress in defining population differences and the application of statistical methods to improve association studies. It is now possible to take into account the confounding effects of population stratification using thousands of unselected genome-wide single-nucleotide polymorphisms or, alternatively, selected panels of ancestry informative markers. These methods do not require any demographic information and therefore can be widely applied to genotypes available from multiple sources. We further suggest that it will be important to explore results in homogeneous population subsets as we seek to define the extent to which genomic variation influences complex phenotypes.

  7. Extended stellar substructure surrounding the Bo\\"otes I dwarf spheroidal galaxy

    CERN Document Server

    Roderick, T A; Jerjen, H; Da Costa, G S

    2016-01-01

    We present deep stellar photometry of the Bo\\"otes I dwarf spheroidal galaxy in g and i band filters, taken with the Dark Energy Camera at Cerro Tololo in Chile. Our analysis reveals a large, extended region of stellar substructure surrounding the dwarf, as well as a distinct over-density encroaching on its tidal radius. A radial profile of the Bo\\"otes I stellar distribution shows a break radius indicating the presence of extra-tidal stars. These observations strongly suggest that Bo\\"otes I is experiencing tidal disruption, although not as extreme as that exhibited by the Hercules dwarf spheroidal. Combined with revised velocity dispersion measurements from the literature, we see evidence suggesting the need to review previous theoretical models of the Bo\\"otes I dwarf spheroidal galaxy.

  8. Measuring the power spectrum of dark matter substructure using strong gravitational lensing

    CERN Document Server

    Hezaveh, Yashar; Holder, Gilbert; Kisner, Theodore; Kuhlen, Michael

    2014-01-01

    In recent years, it has become possible to detect individual dark matter subhalos near strong gravitational lenses. Typically, only the most massive subhalos in the strong lensing region may be detected this way. In this work, we show that strong lenses may also be used to constrain the much more numerous population of lower mass subhalos that are too small to be detected individually. In particular, we show that the power spectrum of projected density fluctuations in galaxy halos can be measured using strong gravitational lensing. We develop the mathematical framework of power spectrum estimation, and test our method on mock observations. We use our results to determine the types of observations required to measure the substructure power spectrum with high significance. We predict that deep observations with current facilities (in particular ALMA) can measure this power spectrum, placing strong constraints on the abundance of dark matter subhalos and the underlying particle nature of dark matter.

  9. The Genetics of Mexico Recapitulates Native American Substructure and Affects Biomedical Traits

    Science.gov (United States)

    Moreno-Estrada, Andrés; Gignoux, Christopher R.; Fernández-López, Juan Carlos; Zakharia, Fouad; Sikora, Martin; Contreras, Alejandra V.; Acuña-Alonzo, Victor; Sandoval, Karla; Eng, Celeste; Romero-Hidalgo, Sandra; Ortiz-Tello, Patricia; Robles, Victoria; Kenny, Eimear E.; Nuño-Arana, Ismael; Barquera-Lozano, Rodrigo; Macín-Pérez, Gastón; Granados-Arriola, Julio; Huntsman, Scott; Galanter, Joshua M.; Via, Marc; Ford, Jean G.; Chapela, Rocío; Rodriguez-Cintron, William; Rodríguez-Santana, Jose R.; Romieu, Isabelle; Sienra-Monge, Juan José; Navarro, Blanca del Rio; London, Stephanie J.; Ruiz-Linares, Andrés; Garcia-Herrera, Rodrigo; Estrada, Karol; Hidalgo-Miranda, Alfredo; Jimenez-Sanchez, Gerardo; Carnevale, Alessandra; Soberón, Xavier; Canizales-Quinteros, Samuel; Rangel-Villalobos, Héctor; Silva-Zolezzi, Irma; Burchard, Esteban Gonzalez; Bustamante, Carlos D.

    2014-01-01

    Mexico harbors great cultural and ethnic diversity, yet fine-scale patterns of human genome-wide variation from this region remain largely uncharacterized. We studied genomic variation within Mexico from over 1,000 individuals representing 20 indigenous and 11 mestizo populations. We found striking genetic stratification among indigenous populations within Mexico at varying degrees of geographic isolation. Some groups were as differentiated as Europeans are from East Asians. Pre-Columbian genetic substructure is recapitulated in the indigenous ancestry of admixed mestizo individuals across the country. Furthermore, two independently phenotyped cohorts of Mexicans and Mexican Americans showed a significant association between sub-continental ancestry and lung function. Thus, accounting for fine-scale ancestry patterns is critical for medical and population genetic studies within Mexico, in Mexican-descent populations, and likely in many other populations worldwide. PMID:24926019

  10. Performance of boosted object and jet substructure techniques in Run 1 and 2 ATLAS data

    CERN Document Server

    Schramm, Steven; The ATLAS collaboration

    2016-01-01

    Hadronic decays of heavy particles with momenta much larger than their mass result in their decay products being reconstructable as a single large-radius jet. The study of the substructure of these jets allows the separation of these boosted decays with respect to more common jets from light-quarks and gluons. Several techniques have been developed by the phenomenology and experimental community to identify jets coming from hadronic decays of boosted top quarks, W, Z and Higgs bosons. The performance of several such techniques have been studied in ATLAS using fully-simulated Monte Carlo events, and validated on data using pure samples of top quarks, W bosons from top decays and dijet events. Results of these studies will be presented for Run 1 as well as Run 2 of the LHC.

  11. The substructure of a flux transfer event observed by the MMS spacecraft

    Science.gov (United States)

    Hwang, K.-J.; Sibeck, D. G.; Giles, B. L.; Pollock, C. J.; Gershman, D.; Avanov, L.; Paterson, W. R.; Dorelli, J. C.; Ergun, R. E.; Russell, C. T.; Strangeway, R. J.; Mauk, B.; Cohen, I. J.; Torbert, R. B.; Burch, J. L.

    2016-09-01

    On 15 August 2015, MMS (Magnetospheric Multiscale mission), skimming the dusk magnetopause, detected an isolated region of an increased magnetic strength and bipolar Bn, indicating a flux transfer event (FTE). The four spacecraft in a tetrahedron allowed for investigations of the shape and motion of the FTE. In particular, high-resolution particle data facilitated our exploration of FTE substructures and their magnetic connectivity inside and surrounding the FTE. Combined field and plasma observations suggest that the core fields are open, magnetically connected to the northern magnetosphere from which high-energy particles leak; ion "D" distributions characterize the axis of flux ropes that carry old-opened field lines; counterstreaming electrons superposed by parallel-heated components populate the periphery surrounding the FTE; and the interface between the core and draped regions contains a separatrix of newly opened magnetic field lines that emanate from the X line above the FTE.

  12. On the Recombination Rate Estimation in the Presence of Population Substructure.

    Directory of Open Access Journals (Sweden)

    Julian Hecker

    Full Text Available As recombination events are not uniformly distributed along the human genome, the estimation of fine-scale recombination maps, e.g. HapMap Project, has been one of the major research endeavors over the last couple of years. For simulation studies, these estimates provide realistic reference scenarios to design future study and to develop novel methodology. To achieve a feasible framework for the estimation of such recombination maps, existing methodology uses sample probabilities for a two-locus model with recombination, with recent advances allowing for computationally fast implementations. In this work, we extend the existing theoretical framework for the recombination rate estimation to the presence of population substructure. We show under which assumptions the existing methodology can still be applied. We illustrate our extension of the methodology by an extensive simulation study.

  13. Development of a Probabilistic Component Mode Synthesis Method for the Analysis of Non-Deterministic Substructures

    Science.gov (United States)

    Brown, Andrew M.; Ferri, Aldo A.

    1995-01-01

    Standard methods of structural dynamic analysis assume that the structural characteristics are deterministic. Recognizing that these characteristics are actually statistical in nature, researchers have recently developed a variety of methods that use this information to determine probabilities of a desired response characteristic, such as natural frequency, without using expensive Monte Carlo simulations. One of the problems in these methods is correctly identifying the statistical properties of primitive variables such as geometry, stiffness, and mass. This paper presents a method where the measured dynamic properties of substructures are used instead as the random variables. The residual flexibility method of component mode synthesis is combined with the probabilistic methods to determine the cumulative distribution function of the system eigenvalues. A simple cantilever beam test problem is presented that illustrates the theory.

  14. London Bridge Is Shaking Funny

    Institute of Scientific and Technical Information of China (English)

    1995-01-01

    Bridges generally don’t fall down without warning;they crack first. Searching for cracks is a tedious business,though, and bridge inspectors bave been known to miss them. Charles Farrar,a civil engineer at Los Alamos Na-

  15. Fatigue tests on aluminium bridges

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Straalen, IJ.J. van

    2004-01-01

    Traffic bridges are subjected to variable loads and should therefore be checked on fatigue. Especially low weight materials, like aluminium, are sensitive to fatigue, because the variable load is a substantial part of the total load. This paper shows the structural design of an aluminium bridge load

  16. Fatigue tests on aluminium bridges

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Straalen, IJ.J. van

    2005-01-01

    Traffic bridges are subjected to variable loads and should therefore be checked on fatigue. Especially low weight materials, like aluminium, are sensitive to fatigue, because the variable load is a substantial part of the total load. This paper shows the structural design of an aluminium bridge load

  17. Association between Y haplogroups and autosomal AIMs reveals intra-population substructure in Bolivian populations.

    Science.gov (United States)

    Vullo, Carlos; Gomes, Verónica; Romanini, Carola; Oliveira, Andréa M; Rocabado, Omar; Aquino, Juliana; Amorim, António; Gusmão, Leonor

    2015-07-01

    For the correct evaluation of the weight of genetic evidence in a forensic context, databases must reflect the structure of the population, with all possible groups being represented. Countries with a recent history of admixture between strongly differentiated populations are usually highly heterogeneous and sub-structured. Bolivia is one of these countries, with a high diversity of ethnic groups and different levels of admixture (among Native Americans, Europeans and Africans) across the territory. For a better characterization of the male lineages in Bolivia, 17 Y-STR and 42 Y-SNP loci were genotyped in samples from La Paz and Chuquisaca. Only European and Native American Y-haplogroups were detected, and no sub-Saharan African chromosomes were found. Significant differences were observed between the two samples, with a higher frequency of European lineages in Chuquisaca than in La Paz. A sample belonging to haplogroup Q1a3a1a1-M19 was detected in La Paz, in a haplotype background different from those previously found in Argentina. This result supports an old M19 North-south dispersion in South America, possibly via two routes. When comparing the ancestry of each individual assessed through his Y chromosome with the one estimated using autosomal AIMs, (a) increased European ancestry in individuals with European Y chromosomes and (b) higher Native American ancestry in the carriers of Native American Y-haplogroups were observed, revealing an association between autosomal and Y-chromosomal markers. The results of this study demonstrate that a sub-structure does exist in Bolivia at both inter- and intrapopulation levels, a fact which must be taken into account in the evaluation of forensic genetic evidence.

  18. Two-body wear of dental porcelain and substructure oxide ceramics.

    Science.gov (United States)

    Rosentritt, Martin; Preis, Verena; Behr, Michael; Hahnel, Sebastian; Handel, Gerhard; Kolbeck, Carola

    2012-06-01

    The aim of this in vitro study was to investigate the two-body wear of different ceramics. Two-body wear tests were performed in a chewing simulator with steatite and enamel antagonists, respectively. Specimens were loaded in a pin-on-block design with a vertical load of 50 N for 1.2 × 10(5) cycles; (f = 1.6 Hz; lateral movement, 1 mm; mouth opening: 2 mm). Human enamel was used as a reference. Three zirconia ceramics, three veneering porcelains, two glass-infiltrated and one lithium disilicate ceramic were investigated. Veneering and lithium disilicate ceramics were glazed before testing. Surface roughness Ra (SP6, Perthen-Feinprüf, G) and wear depth were determined using a 3D scanner (Laserscan 3D, Willytec, G). SEM (Quanta FEG 400, FEI, USA) pictures of the worn specimens and antagonists were made for evaluating wear performance. Veneering porcelain provided wear traces between 71.2 and 124.1 μm (enamel antagonist) and 117.4 and 274.1 μm (steatite). Wear of the steatite antagonists varied between 0.618 and 2.85 mm². No wear was found for zirconia and glass-infiltrated substructure ceramics. Also, no wear was found for the corresponding antagonists. Wear of specimens and antagonists was strongly material dependent. No visible wear was found on zirconia and glass-infiltrated ceramics. Porcelain and lithium disilicate ceramic showed a comparable or lower wear than the enamel reference. Antagonist wear was found to be lower when specimens were made of substructure oxide ceramics instead of veneering porcelain. From the point of wear testing, zirconia may be used for the fabrication of fixed dental prosthesis without veneering.

  19. THE NEXT GENERATION VIRGO CLUSTER SURVEY. XIX. TOMOGRAPHY OF MILKY WAY SUBSTRUCTURES IN THE NGVS FOOTPRINT

    Energy Technology Data Exchange (ETDEWEB)

    Lokhorst, Deborah; Starkenburg, Else; Navarro, Julio F. [Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 1A1, Canada (Canada); McConnachie, Alan W.; Ferrarese, Laura; Côté, Patrick; Gwyn, Stephen D. J. [National Research Council, Herzberg Astronomy and Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Liu, Chengze [Center for Astronomy and Astrophysics, Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China); Peng, Eric W. [Department of Astronomy, Peking University, Beijing 100871 (China); Cuillandre, Jean-Charles [CEA/IRFU/SAP, Laboratoire AIM Paris-Saclay, CNRS/INSU, Université Paris Diderot, Observatoire de Paris, PSL Research University, F-91191 Gif-sur-Yvette Cedex (France); Guhathakurta, Puragra, E-mail: dml@uvic.ca [Department of Astronomy and Astrophysics, University of California Santa Cruz, 1156 High Street, Santa Cruz, CA 95064 (United States)

    2016-03-10

    The Next Generation Virgo Cluster Survey (NGVS) is a deep u*giz survey targeting the Virgo Cluster of galaxies at 16.5 Mpc. This survey provides high-quality photometry over an ∼100 deg{sup 2} region straddling the constellations of Virgo and Coma Berenices. This sightline through the Milky Way is noteworthy in that it intersects two of the most prominent substructures in the Galactic halo: the Virgo overdensity (VOD) and Sagittarius stellar stream (close to its bifurcation point). In this paper, we use deep u*gi imaging from the NGVS to perform tomography of the VOD and Sagittarius stream using main-sequence turnoff (MSTO) stars as a halo tracer population. The VOD, whose centroid is known to lie at somewhat lower declinations (α ∼ 190°, δ ∼ −5°) than is covered by the NGVS, is nevertheless clearly detected in the NGVS footprint at distances between ∼8 and 25 kpc. By contrast, the Sagittarius stream is found to slice directly across the NGVS field at distances between 25 and 40 kpc, with a density maximum at ≃35 kpc. No evidence is found for new substructures beyond the Sagittarius stream, at least out to a distance of ∼90 kpc—the largest distance to which we can reliably trace the halo using MSTO stars. We find clear evidence for a distance gradient in the Sagittarius stream across the ∼30° of sky covered by the NGVS and its flanking fields. We compare our distance measurements along the stream with those predicted by leading stream models.

  20. Development of cooperative system bridges

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhe; WAN Qi-bai; SHI Lei

    2008-01-01

    Cooperative system bridges comprise several basic structures that act jointly to improve structural characteristics. We delved into the historical development of cooperative system bridges. Cooperative systems are classified as different-load cooperative systems and same-load cooperative systems by distinguishing the modes of load distribution. For different-load cooperation, individual basic structures are at different positions in the direction along bridge axis and carry the loads separately. While for same-load cooperation, all basic structures overlap in geometrical locations and support the entire loads conjointly. The choosing of span ratios between basic structures, the design of connections of different-load cooperative systems were discussed as well as optimizations of relative rigidity for same-load cooperative systems which greatly influence structural characteristics. The general situation and several structural measurements of several cooperative bridges were demonstrated. This information can assist engineers in developing their concepts in cooperative systems and can lead to more efficient and economical cooperative bridges.

  1. Linguistic Barriers and Bridges

    DEFF Research Database (Denmark)

    Thuesen, Frederik

    2016-01-01

    and intercultural communication, this article analyses interviews with 31 employees from two highly ethnically diverse Danish workplaces. The article shows how linguistic barriers such as different levels of majority language competence and their consequent misunderstandings breed mistrust and hostility, whilst......The influence of language on social capital in low-skill and ethnically diverse workplaces has thus far received very limited attention within the sociology of work. As the ethnically diverse workplace is an important social space for the construction of social relations bridging different social...... groups, the sociology of work needs to develop a better understanding of the way in which linguistic diversity influences the formation of social capital, i.e. resources such as the trust and reciprocity inherent in social relations in such workplaces. Drawing on theories about intergroup contact...

  2. Looking Beyond the Bridge

    DEFF Research Database (Denmark)

    Jahn, Elke; Rosholm, Michael

    We perform a comprehensive analysis of the stepping-stone effect of temporary agency employment on unemployed workers. Using the timing-of-events approach, we not only investigate whether agency employment is a bridge into regular employment but also analyze its effect on post-unemployment wages ...... is even more effective in tight labor markets, where firms use agency employment primarily to screen po-tential candidates for permanent posts. Finally, our results suggest that agency employment may improve subsequent match quality in terms of wages and job duration....... and job stability for unemployed Danish workers. We find evidence of large positive treatment effects, particularly for immigrants. There is also some indication that higher treatment intensity increases the likelihood of leav-ing unemployment for regular jobs. Our results show that agency employment...

  3. Cascaded resonant bridge converters

    Science.gov (United States)

    Stuart, Thomas A. (Inventor)

    1989-01-01

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

  4. Torsional instability in suspension bridges: The Tacoma Narrows Bridge case

    Science.gov (United States)

    Arioli, Gianni; Gazzola, Filippo

    2017-01-01

    All attempts of aeroelastic explanations for the torsional instability of suspension bridges have been somehow criticised and none of them is unanimously accepted by the scientific community. We suggest a new nonlinear model for a suspension bridge and we perform numerical experiments with the parameters corresponding to the collapsed Tacoma Narrows Bridge. We show that the thresholds of instability are in line with those observed the day of the collapse. Our analysis enables us to give a new explanation for the torsional instability, only based on the nonlinear behavior of the structure.

  5. Cross spectral energy method for damage assessment of the cable-stayed bridge under operational conditions

    Institute of Scientific and Technical Information of China (English)

    Yang Hezhen; Li Huajun

    2008-01-01

    The new cross spectral energy method (CSEM) is proposed for maintaining cable-stayed bridge safety by the measurable output-only vibration response.Damage assessment of real structures is limited by a series of problems such as unknown ambient excitation forces, errors introduced by system identification,incomplete dynamic measurements, etc.Thus the methodology based on cross spectral energy of each substructure member is derived to meet these challenges.The novel damage index does not require any modal or parameter identification technology.It can be calculated directly from vibration test data.In order to evaluate the efficiency of the presented methodology, a three dimensional (3D) actual cable-stayed bridge model with one or more damaged positions under operational conditions was studied.In order to testify the reliability of damage detection method, the response data was polluted by the random noise.It is proved that the proposed method can successfully localize all damage cases even in noisy data.With the help of examples, the CSEM can potentially be applied as a nondestructive evaluation technique (NDT) for on-line health monitoring of cable-stayed bridges with minimum disruption of its operations.

  6. National Bridge Inventory - National Geospatial Data Asset (NGDA) Bridges

    Data.gov (United States)

    Department of Transportation — The NBI (NTAD 2015) is a collection of information (database) describing the more than 610,000 of the Nation's bridges located on public roads, including Interstate...

  7. Bridge Creek IMW database - Bridge Creek Restoration and Monitoring Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The incised and degraded habitat of Bridge Creek is thought to be limiting a population of ESA-listed steelhead (Oncorhynchus mykiss). A logical restoration approach...

  8. General design of Sutong Bridge

    Institute of Scientific and Technical Information of China (English)

    Zhang Xigang; Yuan Hong; Pei Minshan; Dai Jie; Xu Lin

    2009-01-01

    The main span of Sutong Bridge is a double-pylon, double-plane cable-stayed bridge with steel box girder, which has the world's longest central span of 1 088 m within cable-stayed bridges. To overcome problems caused by severe meteorological conditions, perplexing hydrological conditions, deep buried bedrock and higher navigation level, many new technics and methods were created. Keys including structural system, steel box girder, stayed cable, tower, pier, tower foundation, collision avoidance system, wind-resistance, seismic-resistance, structural nonlinear response and structural static stability were presented individually in this paper.

  9. Reliability Assessment of Concrete Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Middleton, C. R.

    This paper is partly based on research performed for the Highways Agency, London, UK under the project DPU/9/44 "Revision of Bridge Assessment Rules Based on Whole Life Performance: concrete bridges". It contains the details of a methodology which can be used to generate Whole Life (WL) reliability...... profiles. These WL reliability profiles may be used to establish revised rules for concrete bridges. This paper is to some extend based on Thoft-Christensen et. al. [1996], Thoft-Christensen [1996] et. al. and Thoft-Christensen [1996]....

  10. The Higgs Bridge

    CERN Document Server

    Allen, Roland E

    2013-01-01

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

  11. Mineral bridges in nacre revisited

    CERN Document Server

    Checa, Antonio G; Willinger, Marc-Georg

    2012-01-01

    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.

  12. Substructuring of multibody systems for numerical transfer path analysis in internal combustion engines

    Science.gov (United States)

    Acri, Antonio; Offner, Guenter; Nijman, Eugene; Rejlek, Jan

    2016-10-01

    Noise legislations and the increasing customer demands determine the Noise Vibration and Harshness (NVH) development of modern commercial vehicles. In order to meet the stringent legislative requirements for the vehicle noise emission, exact knowledge of all vehicle noise sources and their acoustic behavior is required. Transfer path analysis (TPA) is a fairly well established technique for estimating and ranking individual low-frequency noise or vibration contributions via the different transmission paths. Transmission paths from different sources to target points of interest and their contributions can be analyzed by applying TPA. This technique is applied on test measurements, which can only be available on prototypes, at the end of the designing process. In order to overcome the limits of TPA, a numerical transfer path analysis methodology based on the substructuring of a multibody system is proposed in this paper. Being based on numerical simulation, this methodology can be performed starting from the first steps of the designing process. The main target of the proposed methodology is to get information of noise sources contributions of a dynamic system considering the possibility to have multiple forces contemporary acting on the system. The contributions of these forces are investigated with particular focus on distribute or moving forces. In this paper, the mathematical basics of the proposed methodology and its advantages in comparison with TPA will be discussed. Then, a dynamic system is investigated with a combination of two methods. Being based on the dynamic substructuring (DS) of the investigated model, the methodology proposed requires the evaluation of the contact forces at interfaces, which are computed with a flexible multi-body dynamic (FMBD) simulation. Then, the structure-borne noise paths are computed with the wave based method (WBM). As an example application a 4-cylinder engine is investigated and the proposed methodology is applied on the

  13. The stories of two bridges in Ghana

    DEFF Research Database (Denmark)

    Andreasen, Jørgen

    2004-01-01

    Public participation in bridge building was promoted by un habitat in the village of Mankrong. The neighbouring village did not participate in the construction of their bridge. The first flooding washed the second bridge down while the "participative bridge" stood up....

  14. Distribution of distances between dislocations in different types of dislocation substructures in deformed Cu-Al alloys

    Energy Technology Data Exchange (ETDEWEB)

    Trishkina, L., E-mail: trishkina.53@mail.ru; Zboykova, N.; Koneva, N., E-mail: koneva@tsuab.ru; Kozlov, E. [Tomsk State University of Architecture and Building, 2 Solyanaya St., Tomsk, 634003 (Russian Federation); Cherkasova, T. [Tomsk State University of Architecture and Building, 2 Solyanaya St., Tomsk, 634003 (Russian Federation); National Research Tomsk Polytechnic University, 50 Lenin Ave., Tomsk, 634050 (Russian Federation)

    2016-01-15

    The aim of the investigation was the determination of the statistic description of dislocation distribution in each dislocation substructures component forming after different deformation degrees in the Cu-Al alloys. The dislocation structures were investigated by the transmission diffraction electron microscopy method. In the work the statistic description of distance distribution between the dislocations, dislocation barriers and dislocation tangles in the deformed Cu-Al alloys with different concentration of Al and test temperature at the grain size of 100 µm was carried out. It was established that the above parameters influence the dislocation distribution in different types of the dislocation substructures (DSS): dislocation chaos, dislocation networks without disorientation, nondisoriented and disoriented cells, in the walls and inside the cells. The distributions of the distances between dislocations in the investigated alloys for each DSS type formed at certain deformation degrees and various test temperatures were plotted.

  15. Towards the understanding of jet substructures and cross sections in heavy ion collisions using soft collinear effective theory

    CERN Document Server

    Chien, Yang-Ting

    2016-01-01

    The jet quenching phenomenon in heavy ion collisions provides a strong evidence of the modification of parton shower in the quark-gluon plasma (QGP). Jet substructure observables can probe various aspects of the jet formation mechanism. They contain useful information about the QGP and allow us to study the medium properties in great details. Here we present theoretical calculations of jet shapes and cross sections in proton-proton and lead-lead collisions at the LHC using soft-collinear effective theory, with Glauber gluon interactions in the medium. We find that resumming large logarithms in the jet substructure calculation is necessary for precise theoretical predictions. The resummation is performed using renormalization group evolution between characteristic jet scales. We also find that the medium induces power corrections to jet shapes. In the end we present the comparison between our calculations with the recent measurements at the LHC with very good agreement. Our calculations help initiate precise j...

  16. Radial distribution and strong lensing statistics of satellite galaxies and substructure using high resolution LCDM hydrodynamical simulations

    CERN Document Server

    Maccio, A V; Stadel, J; Diemand, J; Maccio', Andrea V.; Moore, Ben; Stadel, Joachim; Diemand, Juerg

    2006-01-01

    We analyse the number density and radial distribution of substructures and satellite galaxies using cosmological simulations that follow the gas dynamics of a baryonic component, including shock heating, radiative cooling and star formation within the hierarchical concordance LCDM model. We find that the dissipation of the baryons greatly enhances the survival of subhaloes, expecially in the galaxy core, resulting in a radial distribution of satellite galaxies that closely follows the overall mass distribution. Hydrodynamical simulations are necessary to resolve the adiabatic contraction and dense cores of galaxies, resulting in a total number of satellites a factor of two larger than found in pure dark matter simulation. Convergence tests show that the cored distribution found by previous authors was due to physical overmerging of dark matter only structures. We proceed to use a ray-shooting technique in order to study the impact of these additional substructures on the number of violations of the cusp caust...

  17. Redundancy Evaluation of Fracture Critical Bridges

    OpenAIRE

    Bapat, Amey Vivek

    2014-01-01

    Cases of brittle fractures in major bridges prompted AASHTO to publish its first fracture control plan in 1978. It focused on material and fabrication standards, and required periodic 24-month hands-on inspection of bridges with fracture critical members. The practical result of this plan was to significantly increase the life cycle cost of these bridges, rendering them uneconomical. Apart from the Point Pleasant Bridge that failed in 1967, no other bridge has collapsed in the USA following a...

  18. Environmental life cycle assessment comparison between two bridge types: reinforced concrete bridge and steel composite bridge

    DEFF Research Database (Denmark)

    Du, Guangli; Karoumi, Raid

    2013-01-01

    not been integrated into the decision-making process. This paper presents a systematic LCA method for quantifying the environmental impacts for bridges. The comparison study is performed between a reinforced concrete bridge and a steel bridge as an alternative design, with several key maintenance and EOL...... scenarios outlined. LCA study is performed with the ReCiPe methodology with life cycle inventories data from public database. Five selected mid-point level impact categories and the energy consumption are presented. The result shows that the steel bridge has a better environmental performance due...... to the recycling strategy, while the initial material manufacture is the most dominant phase that contributes large environmental impact in both design solutions....

  19. THE BOLOCAM GALACTIC PLANE SURVEY. XI. TEMPERATURES AND SUBSTRUCTURE OF GALACTIC CLUMPS BASED ON 350 μM OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Merello, Manuel; Evans II, Neal J. [The University of Texas at Austin, Department of Astronomy, 2515 Speedway, Stop C1400, Austin, TX 78712-1205 (United States); Shirley, Yancy L. [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Rosolowsky, Erik [Department of Physics, 4-181 CCIS, University of Alberta, Edmonton, AB T6G 2E1 (Canada); Ginsburg, Adam [European Southern Observatory, ESO Headquarters, Karl-Schwarzschild-Strasse 2, D-95748 Garching bei Munchen (Germany); Bally, John [CASA, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Battersby, Cara; Dunham, Michael M., E-mail: manuel@astro.as.utexas.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 78, Cambridge, MA 02138 (United States)

    2015-05-15

    We present 107 maps of continuum emission at 350 μm from Galactic molecular clumps. Observed sources were mainly selected from the Bolocam Galactic Plane Survey (BGPS) catalog, with three additional maps covering star-forming regions in the outer Galaxy. The higher resolution of the SHARC-II images (8.″5 beam) compared with the 1.1 mm images from BGPS (33″ beam) allowed us to identify a large population of smaller substructures within the clumps. A catalog is presented for the 1386 sources extracted from the 350 μm maps. The color temperature distribution of clumps based on the two wavelengths has a median of 13.3 K and mean of 16.3 ± 0.4 K, assuming an opacity law index of 1.7. For the structures with good determination of color temperatures, the mean ratio of gas temperature, determined from NH{sub 3} observations, to dust color temperature is 0.88 and the median ratio is 0.76. About half the clumps have more than 2 substructures and 22 clumps have more than 10. The fraction of the mass in dense substructures seen at 350 μm compared to the mass of their parental clump is ∼0.19, and the surface densities of these substructures are, on average, 2.2 times those seen in the clumps identified at 1.1 mm. For a well-characterized sample, 88 structures (31%) exceed a surface density of 0.2 g cm{sup −2}, and 18 (6%) exceed 1.0 g cm{sup −2}, thresholds for massive star formation suggested by theorists.

  20. Searching for dwarf spheroidal galaxies and other galactic dark matter substructures with the Fermi large area telescope

    Energy Technology Data Exchange (ETDEWEB)

    Drlica-Wagner, Alex [Stanford Univ., CA (United States). Dept. of Physics

    2013-08-01

    Over the past century, it has become clear that about a quarter of the known universe is composed of an invisible, massive component termed ''dark matter''. Some of the most popular theories of physics beyond the Standard Model suggest that dark matter may be a new fundamental particle that could self-annihilate to produce γ rays. Nearby over-densities in the dark matter halo of our Milky Way present some of the most promising targets for detecting the annihilation of dark matter. We used the Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope to search for γ rays produced by dark matter annihilation in Galactic dark matter substructures. We searched for γ-ray emission coincident with Milky Way dwarf spheroidal satellite galaxies, which trace the most massive Galactic dark matter substructures. We also sought to identify nearby dark matter substructures that lack all astrophysical tracers and would be detectable only through γ-ray emission from dark matter annihilation. We found no conclusive evidence for γ-ray emission from dark matter annihilation, and we set stringent and robust constraints on the dark matter annihilation cross section. While γ-ray searches for dark matter substructure are currently the most sensitive and robust probes of dark matter annihilation, they are just beginning to intersect the theoretically preferred region of dark matter parameter space. Thus, we consider future prospects for increasing the sensitivity of γ-ray searches through improvements to the LAT instrument performance and through upcoming wide- field optical surveys.

  1. A Substructure Combination Strategy To Create Potent and Selective Transthyretin Kinetic Stabilizers That Prevent Amyloidogenesis and Cytotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sungwook; Reixach, Natlia; Connelly, Stephen; Johnson, Steven M.; Wilson, Ian A.; Kelly, Jeffery W. (Scripps)

    2010-08-13

    Transthyretin aggregation-associated proteotoxicity appears to cause several human amyloid diseases. Rate-limiting tetramer dissociation and monomer misfolding of transthyretin (TTR) occur before its aggregation into cross-{beta}-sheet amyloid fibrils. Small molecule binding to and preferential stabilization of the tetrameric state of TTR over the dissociative transition state raises the kinetic barrier for dissociation, imposing kinetic stabilization on TTR and preventing aggregation. This is an effective strategy to halt neurodegeneration associated with polyneuropathy, according to recent placebo-controlled clinical trial results. In three recent papers, we systematically ranked possibilities for the three substructures composing a typical TTR kinetic stabilizer, using fibril inhibition potency and plasma TTR binding selectivity data. Herein, we have successfully employed a substructure combination strategy to use these data to develop potent and selective TTR kinetic stabilizers that rescue cells from the cytotoxic effects of TTR amyloidogenesis. Of the 92 stilbene and dihydrostilbene analogues synthesized, nearly all potently inhibit TTR fibril formation. Seventeen of these exhibit a binding stoichiometry of >1.5 of a maximum of 2 to plasma TTR, while displaying minimal binding to the thyroid hormone receptor (<20%). Six analogues were definitively categorized as kinetic stabilizers by evaluating dissociation time-courses. High-resolution TTR-(kinetic stabilizer)2 crystal structures (1.31-1.70 {angstrom}) confirmed the anticipated binding orientation of the 3,5-dibromo-4-hydroxyphenyl substructure and revealed a strong preference of the isosteric 3,5-dibromo-4-aminophenyl substructure to bind to the inner thyroxine binding pocket of TTR.

  2. Near-Field cosmology with RR Lyrae variable stars: A first view of substructure in the southern sky

    CERN Document Server

    Duffau, S; Navarrete, C; Catelan, M; Hajdu, G; Torrealba, G; Cortes, C; Belokurov, V; Koposov, S; Drake, A J

    2016-01-01

    We present an update of a spectroscopic follow-up survey at low-resolution of a large number of RR Lyrae halo overdensity candidates found in the southern sky. The substructure candidates were identified in the RR Lyrae catalog of Torrealba et al. (2015) using Catalina Real-time Transient Survey (CRTS) data. Radial velocities and mean metallicities have been estimated for target stars in almost half of the original overdensities to assess their potential membership to coherent halo features.

  3. Boosting the charged Higgs search prospects using jet substructure at the LHC

    Science.gov (United States)

    Li, Jinmian; Patrick, Riley; Sharma, Pankaj; Williams, Anthony G.

    2016-11-01

    Charged Higgs bosons are predicted in variety of theoretically well-motivated new physics models with extended Higgs sectors. In this study, we focus on a type-II two Higgs doublet model (2HDM-II) and consider a heavy charged Higgs with its mass ranging from 500 GeV to 1 TeV as dictated by the b → sγ constraints which render M H ± > 480 GeV. We study the dominant production mode H ± t associated production with H ± → W ± A being the dominant decay channel when the pseudoscalar A is considerably lighter. For such a heavy charged Higgs, both the decay products W ± and A are relatively boosted. In such a scenario, we apply the jet substructure analysis of tagging the fat pseudoscalar and W jets in order to eliminate the standard model background efficiently. We perform a detailed detector simulation for the signal and background processes at the 14 TeV LHC. We introduce various kinematical cuts to determine the signal significance for a number of benchmark points with charged Higgs boson mass from 500 GeV to 1 TeV in the W ± A decay channel. Finally we perform a multivariate analysis utilizing a boosted decision tree algorithm to optimize these significances.

  4. Detecting Mass Substructure in Galaxy Clusters: An Aperture Mass Statistic for Gravitational Flexion

    CERN Document Server

    Leonard, Adrienne; Wilkins, Stephen M

    2008-01-01

    Gravitational flexion has recently been introduced as a technique by which one can map out and study substructure in clusters of galaxies. Previous analyses involving flexion have measured the individual galaxy-galaxy flexion signal, or used either parametric techniques or a KSB-type inversion to reconstruct the mass distribution in Abell 1689. In this paper, we present an aperture mass statistic for flexion, and apply it to the lensed images of background galaxies obtained by ray-tracing simulations through a simple analytic mass distribution and through a galaxy cluster from the Millennium simulation. We show that this method is effective at detecting and accurately tracing structure within clusters of galaxies on sub-arcminute scales with high signal-to-noise even using a moderate background source number density and image resolution. In addition, the method provides much more information about both the overall shape and the small-scale structure of a cluster of galaxies than can be achieved through a weak...

  5. Chemical Abundances of Planetary Nebulae in the Substructures of M31

    CERN Document Server

    Fang, Xuan; Guerrero, Martin A; Liu, Xiaowei; Yuan, Haibo; Zhang, Yong; Zhang, Bing

    2015-01-01

    We present deep spectroscopy of planetary nebulae (PNe) that are associated with the substructures of the Andromeda Galaxy (M31). The spectra were obtained with the OSIRIS spectrograph on the 10.4 m GTC. Seven targets were selected for the observations, three in the Northern Spur and four associated with the Giant Stream. The most distant target in our sample, with a rectified galactocentric distance >100 kpc, was the first PN discovered in the outer streams of M31. The [O III] 4363 auroral line was well detected in the spectra of all targets, enabling electron temperature determination. Ionic abundances are derived based on the [O III] temperatures, and elemental abundances of helium, nitrogen, oxygen, neon, sulfur, and argon are estimated. The relatively low N/O and He/H ratios as well as abundance ratios of alpha-elements indicate that our target PNe might belong to populations as old as ~2 Gyr. Our PN sample, including the current seven and the previous three observed by Fang et al., have rather homogeneo...

  6. Differential association with cellular substructures of pseudorabies virus DNA during early and late phases of replication

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Porat, T.; Veach, R.A.; Blankenship, M.L.; Kaplan, A.S.

    1984-12-01

    Pseudorabies virus DNA synthesis can be divided into two phases, early and late, which can be distinguished from each other on the basis of the structures of the replicating DNA. The two types of replicating virus DNA can also be distinguished from each other on the basis of the cellular substructures with which each is associated. Analysis by electron microscopic autoradiography showed that during the first round of replication, nascent virus DNA was found in the vicinity of the nuclear membrane; during later rounds of replication the nascent virus DNA was located centrally within the nucleus. The degree of association of virus DNA synthesized at early and late phases with the nuclear matrix fractions also differed; a larger proportion of late than of early nascent virus DNA was associated with this fraction. While nascent cellular DNA only was associated in significant amounts with the nuclear matrix fraction, a large part (up to 40%) of all the virus DNA remained associated with this fraction. However, no retention of specific virus proteins in this fraction was observed. Except for two virus proteins, which were preferentially extracted from the nuclear matrix, approximately 20% of all virus proteins remained in the nuclear matrix fraction. The large proportion of virus DNA associated with the nuclear fraction indicated that virus DNA may be intimately associated with some proteins.

  7. Boosting the charged Higgs search prospects using jet substructure at the LHC

    CERN Document Server

    Li, Jinmian; Sharma, Pankaj; Williams, Anthony G

    2016-01-01

    Charged Higgs bosons are predicted in variety of theoretically well-motivated new physics models with extended Higgs sectors. In this study, we focus on a type-II two Higgs doublet model (2HDM-II) and consider a heavy charged Higgs with its mass ranging from 500 GeV to 1 TeV as dictated by the $b\\to s\\gamma$ constraints which render $M_{H^\\pm}>480$ GeV. We study the dominant production mode $H^\\pm t$ associated production with $H^\\pm \\to W^\\pm A$ being the dominant decay channel when the pseudoscalar $A$ is considerably lighter. For such a heavy charged Higgs, both the decay products $W^\\pm$ and $A$ are relatively boosted. In such a scenario, we apply the jet substructure analysis of tagging the fat pseudoscalar and $W$ jets in order to eliminate the standard model background efficiently. We perform a detailed detector simulation for the signal and background processes at the 14 TeV LHC. We introduce various kinematical cuts to determine the signal significance for a number of benchmark points with charged Hi...

  8. Jet Substructure Classification in High-Energy Physics with Deep Neural Networks

    CERN Document Server

    Baldi, Pierre; Eng, Clara; Sadowski, Peter; Whiteson, Daniel

    2016-01-01

    At the extreme energies of the Large Hadron Collider, massive particles can be produced at such high velocities that their hadronic decays are collimated and the resulting jets overlap. Deducing whether the substructure of an observed jet is due to a low-mass single particle or due to multiple decay objects of a massive particle is an important problem in the analysis of collider data. Traditional approaches have relied on expert features designed to detect energy deposition patterns in the calorimeter, but the complexity of the data make this task an excellent candidate for the application of machine learning tools. The data collected by the detector can be treated as a two-dimensional image, lending itself to the natural application of image classification techniques. In this work, we apply deep neural networks with a mixture of locally-connected and fully-connected nodes. Our experiments demonstrate that without the aid of expert features, such networks match or modestly outperform the current state-of-the...

  9. Analysis of shape memory alloy sensory particles for damage detection via substructure and continuum damage modeling

    Science.gov (United States)

    Bielefeldt, Brent R.; Benzerga, A. Amine; Hartl, Darren J.

    2016-04-01

    The ability to monitor and predict the structural health of an aircraft is of growing importance to the aerospace industry. Currently, structural inspections and maintenance are based upon experiences with similar aircraft operating in similar conditions. While effective, these methods are time-intensive and unnecessary if the aircraft is not in danger of structural failure. It is imagined that future aircraft will utilize non-destructive evaluation methods, allowing for the near real-time monitoring of structural health. A particularly interesting method involves utilizing the unique transformation response of shape memory alloy (SMA) particles embedded in an aircraft structure. By detecting changes in the mechanical and/or electromagnetic responses of embedded particles, operators could detect the formation or propagation of fatigue cracks in the vicinity of these particles. This work focuses on a finite element model of SMA particles embedded in an aircraft wing using a substructure modeling approach in which degrees of freedom are retained only at specified points of connection to other parts or the application of boundary conditions, greatly reducing computational cost. Previous work evaluated isolated particle response to a static crack to numerically demonstrate and validate this damage detection method. This paper presents the implementation of a damage model to account for crack propagation and examine for the first time the effect of particle configuration and/or relative placement with respect to the ability to detect damage.

  10. Detection of lensing substructure using ALMA observations of the dusty galaxy SDP.81

    CERN Document Server

    Hezaveh, Yashar D; Marrone, Daniel P; Mao, Yao-Yuan; Morningstar, Warren; Wen, Di; Blandford, Roger D; Carlstrom, John E; Fassnacht, Christopher D; Holder, Gilbert P; Kemball, Athol; Marshall, Philip J; Murray, Norman; Levasseur, Laurence Perreault; Vieira, Joaquin D; Wechsler, Risa H

    2016-01-01

    We study the abundance of substructure in the matter density near galaxies using ALMA Science Verification observations of the strong lensing system SDP.81. We present a method to measure the abundance of subhalos around galaxies using interferometric observations of gravitational lenses. Using simulated ALMA observations, we explore the effects of various systematics, including antenna phase errors and source priors, and show how such errors may be measured or marginalized. We apply our formalism to ALMA observations of SDP.81. We find evidence for the presence of a $M=10^{8.96\\pm 0.12} M_{\\odot}$ subhalo near one of the images, with a significance of $6.9\\sigma$ in a joint fit to data from bands 6 and 7; the effect of the subhalo is also detected in both bands individually. We also derive constraints on the abundance of dark matter subhalos down to $M\\sim 2\\times 10^7 M_{\\odot}$, pushing down to the mass regime of the smallest detected satellites in the Local Group, where there are significant discrepancies...

  11. Ringed Substructure and a Gap at 1 AU in the Nearest Protoplanetary Disk

    CERN Document Server

    Andrews, Sean M; Zhu, Zhaohuan; Birnstiel, Tilman; Carpenter, John M; Perez, Laura M; Bai, Xue-Ning; Oberg, Karin I; Hughes, A Meredith; Isella, Andrea; Ricci, Luca

    2016-01-01

    We present long-baseline Atacama Large Millimeter/submillimeter Array (ALMA) observations of the 870 micron continuum emission from the nearest gas-rich protoplanetary disk, around TW Hya, that trace millimeter-sized particles down to spatial scales as small as 1 AU (20 mas). These data reveal a series of concentric ring-shaped substructures in the form of bright zones and narrow dark annuli (1-6 AU) with modest contrasts (5-30%). We associate these features with concentrations of solids that have had their inward radial drift slowed or stopped, presumably at local gas pressure maxima. No significant non-axisymmetric structures are detected. Some of the observed features occur near temperatures that may be associated with the condensation fronts of major volatile species, but the relatively small brightness contrasts may also be a consequence of magnetized disk evolution (the so-called zonal flows). Other features, particularly a narrow dark annulus located only 1 AU from the star, could indicate interactions...

  12. Spectroscopic observations of evolving flare ribbon substructure suggesting origin in current sheet waves

    Science.gov (United States)

    Brannon, Sean R.; Longcope, Dana; Qiu, Jiong

    2015-04-01

    A flare ribbon is the chromospheric image of reconnection at a coronal current sheet. The dynamics and structure of the ribbon can thus reveal properties of the current sheet, including motion of the reconnecting flare loops. We present imaging and spectroscopic observations from the Interface Region Imaging Spectrograph (IRIS) of the evolution of a flare ribbon at high spatial resolution and time cadence. These reveal small-scale substructure in the ribbon, which manifest as oscillations in both position and Doppler velocities. We consider various alternative explanations for these oscillations, including modulation of chromospheric evaporation flows. Among these we find the best support for some form of elliptical wave localized to the coronal current sheet, such as a tearing mode or Kelvin-Helmholtz instability.IRIS is a NASA Small Explorer mission developed and operated by Lockheed Martin Solar and Astrophysics Laboratory. This work is supported by contract 8100002702 from Lockheed Martin to Montana State University, a Montana Space Grant Consortium fellowship, and by NASA through HSR.

  13. The Next Generation Virgo Cluster Survey. XIX. Tomography of Milky Way Substructures in the NGVS Footprint

    CERN Document Server

    Lokhorst, Deborah; McConnachie, Alan; Navarro, Julio F; Ferrarese, Laura; Côté, Patrick; Liu, Chengze; Peng, Eric W; Gwyn, Stephen D J; Cuillandre, Jean-Charles; Guhathakurta, Puragra

    2016-01-01

    The Next Generation Virgo Cluster Survey (NGVS) is a deep $u^*giz$ survey targeting the Virgo cluster of galaxies at 16.5~Mpc. This survey provides high-quality photometry over an $\\sim$ 100 deg$^2$ region straddling the constellations of Virgo and Coma Berenices. This sightline through the Milky Way is noteworthy in that it intersects two of the most prominent substructures in the Galactic halo: the Virgo Over-Density (VOD) and Sagittarius stellar stream (close to its bifurcation point). In this paper, we use deep $u^*gi$ imaging from the NGVS to perform tomography of the VOD and Sagittarius stream using main-sequence turnoff (MSTO) stars as a halo tracer population. The VOD, whose centroid is known to lie at somewhat lower declinations ($\\alpha \\sim 190^\\circ$, $\\delta \\sim -5^\\circ$) than is covered by the NGVS, is nevertheless clearly detected in the NGVS footprint at distances between $\\sim$ 8 and 25~kpc. By contrast, the Sagittarius stream is found to slice directly across the NGVS field at distances be...

  14. On the cross-section of Dark Matter using substructure infall into galaxy clusters

    CERN Document Server

    Harvey, David; Massey, Richard; Kitching, Thomas D; Taylor, Andy; Pike, Simon R; Kay, Scott T; Lau, Erwin T; Nagai, Daisuke

    2013-01-01

    We develop a statistical method to measure the interaction cross-section of Dark Matter, exploiting the continuous minor merger events in which small substructures fall into galaxy clusters. We find that by taking the ration of the distances between the galaxies and Dark Matter, and galaxies and gas in accreting sub-halos, we are able to calibrate and measure the Dark Matter self-interaction cross-section, remove any inherent line-of-sight projections. In order to interpret this ratio as a cross-section of Dark Matter we derive an analytical description of sub-halo infall which encompasses; the force of the main cluster potential, the drag on a gas sub-halo, a model for Dark Matter self-interactions and the resulting sub-halo drag, the force on the gas and galaxies due to the Dark Matter sub-halo potential, and finally the buoyancy on the gas and Dark Matter. We create mock observations from cosmological simulations of structure formation and find that collisionless Dark Matter becomes physically separated fr...

  15. Multicolor Photometry of the Galaxy Cluster A98: Substructures and Star Formation Properties

    CERN Document Server

    Zhang, L; Zhou, X; Jiang, Z -J; Yang, Y -B; Ma, J; Wu, J -H; Wu, Z -Y

    2009-01-01

    An optical photometric observation with the Beijing-Arizona-Taiwan-Connecticut (BATC) multicolor system is carried out for A98 (z=0.104), a galaxy cluster with two large enhancements in X-ray surface brightness. The spectral energy distributions (SEDs) covering 15 intermediate bands are obtained for all sources detected down to V ~ 20 mag in a field of $58' \\times 58'$. After the star-galaxy separation by the color-color diagrams, a photometric redshift technique is applied to the galaxy sample for further membership determination. The color-magnitude relation is taken as a further restriction of the early-type cluster galaxies. As a result, a list of 198 faint member galaxies is achieved. Based on newly generated sample of member galaxies, the dynamical substructures, A98N, A98S, and A98W, are investigated in detail. A separate galaxy group, A98X, is also found to the south of main concentration of A98, which is gravitationally unbound to A98. For 74 spectroscopically confirmed member galaxies, the environme...

  16. Ion beam modifications of defect sub-structure of calcite cleavages

    Indian Academy of Sciences (India)

    E Venkateshwar Rao; M Ramakrishna Murthy

    2008-04-01

    Experimental investigations on the defect sub-structure and surface modifications, brought about by He+ ion-bombardment of calcite cleavages (100), have been carried out. Optical and scanning electron microscopic investigations revealed drastic modifications on the surface morphology, local symmetry and defect concentration. Additional structural defects on ion-bombardment of calcite surfaces also have been observed. Changes in shape and form of chemical etch pits are found to be a function of ion-beam energy, as studied by optical microscopy. Radiation damage in calcite has been attributed mainly due to desorption of CO$^{-2}_{3}$ ions from the calcite surfaces, on irradiation. Measurements of surface conductivity on irradiated calcite surfaces have been made employing a four-probe technique. Enhancement of surface conductivity has been considered to be due to an increase in concentration of CO$^{-2}_{3}$ ions formed, on ion irradiation and subsequent thermal stimulation. Planar plastic anisotropy has been studied on irradiated calcite cleavages by measurement of microhardness.

  17. More pieces of the puzzle: chemistry and substructures in the galactic thick disk

    Energy Technology Data Exchange (ETDEWEB)

    Helmi, Amina [Kapteyn Astronomical Institute, University of Groningen, P.O. Box 800, 9700 AV Groningen (Netherlands); Williams, Mary [Astrophysikalisches Institut Potsdam, An der Sternwarte 16, D-14482 Germany (Germany); Freeman, K. C. [Research School of Astronomy and Astrophysics The Australian National University, Cotter Road Weston Creek, ACT 2611 (Australia); Bland-Hawthorn, J. [Sydney Institute for Astronomy, School of Physics A28, University of Sydney, NSW 2006 (Australia); De Silva, G., E-mail: ahelmi@astro.rug.nl, E-mail: mary@aip.de [Australian Astronomical Observatory, P.O. Box 915, North Ryde, NSW 1670 (Australia)

    2014-08-20

    We present a study of the chemical abundances of solar neighborhood stars associated with dynamical structures in the Milky Way's (thick) disk. These stars were identified as an overdensity in the eccentricity range 0.3 < ε < 0.5 in the Copenhagen-Geneva Survey by Helmi et al. We find that stars with these dynamical characteristics do not constitute a homogeneous population. A relatively sharp transition in dynamical and chemical properties appears to occur at a metallicity of [Fe/H] ∼ –0.4. Stars with [Fe/H] > –0.4 have mostly lower eccentricities, smaller vertical velocity dispersions, are α-enhanced, and define a rather narrow sequence in [α/Fe] versus [Fe/H], clearly distinct from that of the thin disk. Stars with [Fe/H] < –0.4 have a range of eccentricities, are hotter vertically, and depict a larger spread in [α/Fe]. We also found tentative evidence of a substructure possibly associated with the disruption of a metal-rich star cluster. The differences between these populations of stars is also present in, e.g., [Zn/Fe], [Ni/Fe], and [SmII/Fe], suggesting a real physical distinction.

  18. The Extraordinary Amount of Substructure in the Hubble Frontier Fields Cluster Abell 2744

    Science.gov (United States)

    Jauzac, M.; Eckert, D.; Schwinn, J.; Harvey, D.; Baugh, C. M.; Robertson, A.; Bose, S.; Massey, R.; Owers, M.; Ebeling, H.; Shan, H. Y.; Jullo, E.; Kneib, J.-P.; Richard, J.; Atek, H.; Clément, B.; Egami, E.; Israel, H.; Knowles, K.; Limousin, M.; Natarajan, P.; Rexroth, M.; Taylor, P.; Tchernin, C.

    2016-09-01

    We present a joint optical/X-ray analysis of the massive galaxy cluster Abell 2744 (z=0.308). Our strong- and weak-lensing analysis within the central region of the cluster, i.e., at R Newton reveal four remnant cores, one of them a new detection, and three shocks. Unlike Merten et al. (2011), we find all cores to have both dark and luminous counterparts. A comparison with clusters of similar mass in the MXXL simulations yields no objects with as many massive substructures as observed in Abell 2744, confirming that Abell 2744 is an extreme system. We stress that these properties still do not constitute a challenge to ΛCDM, as caveats apply to both the simulation and the observations: for instance, the projected mass measurements from gravitational lensing and the limited resolution of the sub-haloes finders. We discuss implications of Abell 2744 for the plausibility of different dark-matter candidates and, finally, measure a new upper limit on the self-interaction cross-section of dark matter of σDM < 1.28 cm2g-1(68% CL), in good agreement with previous results from Harvey et al. (2015).

  19. Exploring a heavy charged Higgs using jet substructure in a fully hadronic channel

    CERN Document Server

    Patrick, Riley; Williams, Anthony G

    2016-01-01

    In the framework of the type-II Two Higgs Doublet Model (2HDM-II) a charged Higgs search strategy is presented for the dominant production mode $gb \\rightarrow tH^\\pm$ at the 14 TeV LHC. We consider the decay process which includes $t \\rightarrow bW^\\pm$ and $H^\\pm \\rightarrow AW^\\pm$, and a fully hadronic final state consisting of $bb\\bar{b}+\\mbox{jets}+X$. Dictated by the $b \\rightarrow s\\gamma$ constraints which render $M_{H^\\pm} > 480$ GeV we study two scenarios in which the charged Higgs mass is 750 GeV and the pseudoscalar Higgs mass is 200 GeV and 500 GeV. In this mass scheme highly boosted final state objects are expected and handled with jet substructure techniques which also acts to suppress the standard model background. A detailed detector analysis is performed, followed by a multivariate analysis involving many kinematic variables to optimize signal to background significance. Finally the LHC search sensitivities for the two scenarios are presented for various integrated luminosities.

  20. GESP: A computer program for modeling genetic effective population size, inbreeding, and divergence in substructured populations.

    Science.gov (United States)

    Olsson, Fredrik; Laikre, Linda; Hössjer, Ola; Ryman, Nils

    2017-03-24

    The genetically effective population size (Ne) is of key importance for quantifying rates of inbreeding and genetic drift, and is often used in conservation management to set targets for genetic viability. The concept was developed for single, isolated populations and the mathematical means for analyzing the expected Ne in complex, subdivided populations have previously not been available. We recently developed such analytical theory and central parts of that work have now been incorporated into a freely available software tool presented here. GESP (Genetic Effective population size, inbreeding, and divergence in Substructured Populations) is R-based and designed to model short and long term patterns of genetic differentiation and effective population size of subdivided populations. The algorithms performed by GESP allow exact computation of global and local inbreeding and eigenvalue effective population size, predictions of genetic divergence among populations (GST) as well as departures from random mating (FIS, FIT) while varying i) subpopulation census and effective size, separately or including trend of the global population size, ii) rate and direction of migration between all pairs of subpopulations, iii) degree of relatedness and divergence among subpopulations, iv) ploidy (haploid or diploid), and v) degree of selfing. Here, we describe GESP and exemplify its use in conservation genetics modeling. This article is protected by copyright. All rights reserved.

  1. Measuring the power spectrum of dark matter substructure using strong gravitational lensing

    Science.gov (United States)

    Hezaveh, Yashar; Dalal, Neal; Holder, Gilbert; Kisner, Theodore; Kuhlen, Michael; Perreault Levasseur, Laurence

    2016-11-01

    In recent years, it has become possible to detect individual dark matter subhalos near images of strongly lensed extended background galaxies. Typically, only the most massive subhalos in the strong lensing region may be detected this way. In this work, we show that strong lenses may also be used to constrain the much more numerous population of lower mass subhalos that are too small to be detected individually. In particular, we show that the power spectrum of projected density fluctuations in galaxy halos can be measured using strong gravitational lensing. We develop the mathematical framework of power spectrum estimation, and test our method on mock observations. We use our results to determine the types of observations required to measure the substructure power spectrum with high significance. We predict that deep observations (~10 hours on a single target) with current facilities can measure this power spectrum at the 3σ level, with no apparent degeneracy with unknown clumpiness in the background source structure or fluctuations from detector noise. Upcoming ALMA measurements of strong lenses are capable of placing strong constraints on the abundance of dark matter subhalos and the underlying particle nature of dark matter.

  2. A Consensus Tree Approach for Reconstructing Human Evolutionary History and Detecting Population Substructure

    Science.gov (United States)

    Tsai, Ming-Chi; Blelloch, Guy; Ravi, R.; Schwartz, Russell

    The random accumulation of variations in the human genome over time implicitly encodes a history of how human populations have arisen, dispersed, and intermixed since we emerged as a species. Reconstructing that history is a challenging computational and statistical problem but has important applications both to basic research and to the discovery of genotype-phenotype correlations. In this study, we present a novel approach to inferring human evolutionary history from genetic variation data. Our approach uses the idea of consensus trees, a technique generally used to reconcile species trees from divergent gene trees, adapting it to the problem of finding the robust relationships within a set of intraspecies phylogenies derived from local regions of the genome. We assess the quality of the method on two large-scale genetic variation data sets: the HapMap Phase II and the Human Genome Diversity Project. Qualitative comparison to a consensus model of the evolution of modern human population groups shows that our inferences closely match our best current understanding of human evolutionary history. A further comparison with results of a leading method for the simpler problem of population substructure assignment verifies that our method provides comparable accuracy in identifying meaningful population subgroups in addition to inferring the relationships among them.

  3. The importance of the cosmic web and halo substructure for power spectra

    CERN Document Server

    Pace, Francesco; Bacon, David J; Crittenden, Robert; Percival, Will J

    2015-01-01

    In this work we study the relevance of the cosmic web and substructures on the matter and lensing power spectra measured from halo mock catalogues extracted from the N-body simulations. Since N-body simulations are computationally expensive, it is common to use faster methods that approximate the dark matter field as a set of halos. In this approximation, we replace mass concentrations in N-body simulations by a spherically symmetric Navarro-Frenk-White halo density profile. We also consider the full mass field as the sum of two distinct fields: dark matter halos ($M>9\\times 10^{12}~M_{\\odot}$/h) and particles not included into halos. Mock halos reproduce well the matter power spectrum, but underestimate the lensing power spectrum on large and small scales. For sources at $z_{\\rm s}=1$ the lensing power spectrum is underestimated by up to 40% at $\\ell\\approx 10^4$ with respect to the simulated halos. The large scale effect can be alleviated by combining the mock catalogue with the dark matter distribution out...

  4. The LHC Search for The CP-odd Higgs by The Jet Substructure Analysis

    CERN Document Server

    Chen, Ning; Liu, Yandong; Liu, Zuowei

    2014-01-01

    The LHC searches for the CP-odd Higgs boson is studied (with masses from 300 GeV to 1 TeV) in the context of the general two-Higgs-doublet model. With the discovery of the 125 GeV Higgs boson at the LHC, we highlight one promising discovery channel of the hZ. This channel can become significant after the global signal fitting to the 125 GeV Higgs boson in the general two-Higgs-doublet model. It is particularly important in the scenario where two CP-even Higgs bosons in the two-Higgs-doublet model have the common mass of 125 GeV. Since the final states involve a Standard-Model-like Higgs boson, we apply the jet substructure analysis of the fat Higgs jet in order to eliminate the Standard Model background sufficiently. After performing the kinematic cuts, we present the LHC search sensitivities for the CP-odd Higgs boson with mass up to 1 TeV via this channel.

  5. Strong lensing signatures of luminous structure and substructure in early-type galaxies

    CERN Document Server

    Gilman, Daniel; Treu, Tommaso; Keeton, Charles R; Nierenberg, Anna M

    2016-01-01

    The arrival times, positions, and fluxes of multiple images in strong lens systems can be used to infer the presence of dark subhalos in the deflector, and thus test predictions of cold dark matter models. However, gravitational lensing does not distinguish between perturbations to a smooth gravitational potential arising from baryonic and non-baryonic mass. In this work, we quantify the extent to which the stellar mass distribution of a deflector can reproduce flux ratio and astrometric anomalies typically associated with the presence of a dark matter subhalo. Using Hubble Space Telescope images of nearby galaxies, we simulate strong lens systems with real distributions of stellar mass as they would be observed at redshift $z_d=0.5$. We add a dark matter halo and external shear to account for the smooth dark matter field, omitting dark substructure, and use a Monte Carlo procedure to characterize the distributions of image positions, time delays, and flux ratios for a compact background source of diameter 5 ...

  6. Jet substructure classification in high-energy physics with deep neural networks

    Science.gov (United States)

    Baldi, Pierre; Bauer, Kevin; Eng, Clara; Sadowski, Peter; Whiteson, Daniel

    2016-05-01

    At the extreme energies of the Large Hadron Collider, massive particles can be produced at such high velocities that their hadronic decays are collimated and the resulting jets overlap. Deducing whether the substructure of an observed jet is due to a low-mass single particle or due to multiple decay objects of a massive particle is an important problem in the analysis of collider data. Traditional approaches have relied on expert features designed to detect energy deposition patterns in the calorimeter, but the complexity of the data make this task an excellent candidate for the application of machine learning tools. The data collected by the detector can be treated as a two-dimensional image, lending itself to the natural application of image classification techniques. In this work, we apply deep neural networks with a mixture of locally connected and fully connected nodes. Our experiments demonstrate that without the aid of expert features, such networks match or modestly outperform the current state-of-the-art approach for discriminating between jets from single hadronic particles and overlapping jets from pairs of collimated hadronic particles, and that such performance gains persist in the presence of pileup interactions.

  7. SHARP - II: Revealing a bias in observational measurements of dark matter substructure with gravitational lens flux ratios

    CERN Document Server

    Hsueh, J - W; Vegetti, S; McKean, J P; Spingola, C; Auger, M W; Koopmans, L V E; Lagattuta, D J

    2016-01-01

    Gravitational lens flux-ratio anomalies provide a powerful technique for measuring dark matter substructure in distant galaxies. However, before using these flux-ratio anomalies to test galaxy formation models, it is imperative to ascertain that the given anomalies are indeed due to the presence of dark matter substructure and not due to some other component of the lensing galaxy halo or to propagation effects. Here we present the case of CLASS~B1555+375, which has a strong radio-wavelength flux-ratio anomaly. Our high-resolution near-infrared Keck~II adaptive optics imaging and archival Hubble Space Telescope data reveal the lensing galaxy in this system to have a clear edge-on disc component that crosses directly over the pair of images that exhibit the flux-ratio anomaly. We find simple models that include the disc can reproduce the cm-wavelength flux-ratio anomaly without requiring additional dark matter substructure. Although further studies are required, our results suggest the assumption that all flux-...

  8. The Akashi Kaikyo Bridge and the Storebælt Bridge

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1999-01-01

    With the completion of the Akashi Kaikyo Bridge and the Storebælt East Bridge the development of the suspension bridge technology in the 20th century has manifested itself in two impressive structures. With the present echnology may bridges of similar (and also more modest) dimensions...... will undoubtedly be built far into the next century. For bridges going beyond the spans of existing bridges it is, however, likely that new concepts will be developed....

  9. River ice jams at bridges

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, D. [New Brunswick Dept. of Transportation, Fredericton, NB (Canada); Beltaos, S. [National Water Research Institute, Burlington, ON (Canada)

    2000-12-01

    Ice jamming, known to cause high water levels at even moderate river flows, is described as both the main and least understood source of ice-related bridge damages. This paper describes a joint study by the New Brunswick Department of Transportation, the Department of the Environment, local governments, and the National Water Research Institute, designed to address problems associated with the interaction of ice jams and bridges. The study consists of collecting information at each of four sites in New Brunswick including: historical data on ice jam locations, causes, and water levels; channel bathymetry, width and slope within each study centred at the respective bridge; and documentation of ice conditions throughout the ice season, including measurement of ice cover thickness, observation of breakup mechanisms, times, causes, characteristics and possible impacts of ice jam release. Data analysis will include determination of high stages due to ice jams or surges caused by upstream ice jam releases, scour potential of surges, and quantification of the structure's capacity to restrain ice movement and to cause jams. The principal objective of the study is to advance beyond empiricism and to develop rational design criteria for bridges by anticipating the effects of climate changes and by incorporating local meteorological and hydrometric records into bridge design for added safety.

  10. Floating liquid bridge charge dynamics

    Science.gov (United States)

    Teschke, Omar; Soares, David Mendez; Gomes, Whyllerson Evaristo; Valente Filho, Juracyr Ferraz

    2016-01-01

    The interaction of liquid with electric fields is investigated in a configuration where up to 13 kV are applied between electrodes resulting in a 106 V/m electric field in the capillaries and where there is the formation of a free-standing fluid bridge in the interelectrode gap. The Mott-Gurney equation was fitted to the measured ionization current vs applied voltage curve which indicates that the ionization rate at the high-voltage anode electrode dimethylsulfoxide (DMSO) interface and space charging in the interelectrode gap determine the floating liquid bridge current for a given cathode-to-anode voltage. Space charge effects were measured in the cathode becker and also at the liquid bridge since the ionized charges at the anode migrate to the bridge outer surface and decrease the interfacial tension from 43 mJ/m2 to 29 mJ/m2. Two distinct structural regions then form the bridge, a charged plastic (bulk modulus ˜100 MPa) conducting outer layer with a surface conductivity of ˜10-9 Ω-1, which shapes and supports the floating fluid structure, and an inner liquid cylinder, where DMSO molecules flow.

  11. A strange bridge by Leonardo

    CERN Document Server

    Huylebrouck, Dirk

    2013-01-01

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

  12. The application of strain field intensity method in the steel bridge fatigue life evaluation

    Science.gov (United States)

    Zhao, Xuefeng; Wang, Yanhong; Cui, Yanjun; Cao, Kaisheng

    2012-04-01

    Asce's survey shows that 80%--90% bridge damage were associated with fatigue and fracture problems. With the operation of vehicle weight and traffic volume increases constantly, the fatigue of welded steel bridge is becoming more and more serious in recent years. A large number of studies show that most prone to fatigue damage of steel bridge is part of the welding position. Thus, it's important to find a more precise method to assess the fatigue life of steel bridge. Three kinds of fatigue analysis method is commonly used in engineering practice, such as nominal stress method, the local stress strain method and field intensity method. The first two methods frequently used for fatigue life assessment of steel bridge, but field intensity method uses less ,and it widely used in fatigue life assessment of aerospace and mechanical. Nominal stress method and the local stress strain method in engineering has been widely applied, but not considering stress gradient and multiaxial stress effects, the accuracy of calculation stability is relatively poor, so it's difficult to fully explain the fatigue damage mechanism. Therefore, it used strain field intensity method to evaluate the fatigue life of steel bridge. The fatigue life research of the steel bridge based on the strain field method and the fatigue life of the I-section plate girder was analyzed. Using Ansys on the elastoplastic finite element analysis determined the dangerous part of the structure and got the stress-strain history of the dangerous point. At the same time, in order to divide the unit more elaborate introduced the sub-structure technology. Finally, it applies K.N. Smith damage equation to calculate the fatigue life of the dangerous point. In order to better simulating the actual welding defects, it dug a small hole in the welding parts. It dug different holds from different view in the welding parts and plused the same load to calculate its fatigue life. Comparing the results found that the welding

  13. Thermal bridges of modern windows

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place; Møller, Eva B.; Nielsen, Anker

    2013-01-01

    With its focus on reduced energy consumption, contemporary housing construction requires a highly insulated and airtight building envelope with as few thermal bridges as possible.Windows must be carefully designed, as thermal bridges can lead to surface condensation or mold growth, even...... if the window has an U-factor of 1 W/(m2·K) or lower. This paper describes the development of modern, energy efficient Danish windows with reduced thermal bridges. It focuses on materials, geometry, and sealing of window panes based on a literature review. Examples of modern windows are presented. Experience...... with the minimum acceptable surface temperature regarding surface condensation or mold growth, implemented in the Danish Building Regulations in 2010, and the calculation method for this temperature based on international standards is discussed. The introduction of the minimum acceptable surface temperature has...

  14. An Expert System for Concrete Bridge Management

    DEFF Research Database (Denmark)

    Brito, J. de; Branco, F. A.; Thoft-Christensen, Palle

    1997-01-01

    management systems are presently being implemented by bridge authorities in several countries. The prototype of an expert system for concrete bridge management is presented in this paper, with its functionality relying on two modules. The inspection module relies on a periodic acquisition of field......The importance of bridge repair versus new bridge construction has risen in recent decades due to high deterioration rates that have been observed in these structures. Budgets both for building new bridges and keeping the existing ones are always limited. To help rational decision-making, bridge...

  15. Determination of the accuracy for targeted irradiations of cellular substructures at SNAKE

    Energy Technology Data Exchange (ETDEWEB)

    Siebenwirth, C. [Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, Munich (Germany); Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Greubel, C. [Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Drexler, S.E. [Department of Radiation Oncology, Ludwig-Maximilians-Universität München, Munich (Germany); Girst, S.; Reindl, J. [Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Walsh, D.W.M. [Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, Munich (Germany); Dollinger, G. [Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Friedl, A.A. [Department of Radiation Oncology, Ludwig-Maximilians-Universität München, Munich (Germany); and others

    2015-04-01

    In the last 10 years the ion microbeam SNAKE, installed at the Munich 14 MV tandem accelerator, has been successfully used for radiobiological experiments by utilizing pattern irradiation without targeting single cells. Now for targeted irradiation of cellular substructures a precise irradiation device was added to the live cell irradiation setup at SNAKE. It combines a sub-micrometer single ion irradiation facility with a high resolution optical fluorescence microscope. Most systematic errors can be reduced or avoided by using the same light path in the microscope for beam spot verification as well as for and target recognition. In addition online observation of the induced cellular responses is possible. The optical microscope and the beam delivering system are controlled by an in-house developed software which integrates the open-source image analysis software, CellProfiler, for semi-automatic target recognition. In this work the targeting accuracy was determined by irradiation of a cross pattern with 55 MeV carbon ions on nucleoli in U2OS and HeLa cells stably expressing a GFP-tagged repair protein MDC1. For target recognition, nuclei were stained with Draq5 and nucleoli were stained with Syto80 or Syto83. The damage response was determined by live-cell imaging of MDC1-GFP accumulation directly after irradiation. No systematic displacement and a random distribution of about 0.7 μm (SD) in x-direction and 0.8 μm (SD) in y-direction were observed. An independent analysis after immunofluorescence staining of the DNA damage marker yH2AX yielded similar results. With this performance a target with a size similar to that of nucleoli (i.e. a diameter of about 3 μm) is hit with a probability of more than 80%, which enables the investigation of the radiation response of cellular subcompartments after targeted ion irradiation in the future.

  16. Assessment of First- and Second-Order Wave-Excitation Load Models for Cylindrical Substructures: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Pereyra, Brandon; Wendt, Fabian; Robertson, Amy; Jonkman, Jason

    2017-03-09

    The hydrodynamic loads on an offshore wind turbine's support structure present unique engineering challenges for offshore wind. Two typical approaches used for modeling these hydrodynamic loads are potential flow (PF) and strip theory (ST), the latter via Morison's equation. This study examines the first- and second-order wave-excitation surge forces on a fixed cylinder in regular waves computed by the PF and ST approaches to (1) verify their numerical implementations in HydroDyn and (2) understand when the ST approach breaks down. The numerical implementation of PF and ST in HydroDyn, a hydrodynamic time-domain solver implemented as a module in the FAST wind turbine engineering tool, was verified by showing the consistency in the first- and second-order force output between the two methods across a range of wave frequencies. ST is known to be invalid at high frequencies, and this study investigates where the ST solution diverges from the PF solution. Regular waves across a range of frequencies were run in HydroDyn for a monopile substructure. As expected, the solutions for the first-order (linear) wave-excitation loads resulting from these regular waves are similar for PF and ST when the diameter of the cylinder is small compared to the length of the waves (generally when the diameter-to-wavelength ratio is less than 0.2). The same finding applies to the solutions for second-order wave-excitation loads, but for much smaller diameter-to-wavelength ratios (based on wavelengths of first-order waves).

  17. ProteMiner-SSM: a web server for efficient analysis of similar protein tertiary substructures

    Science.gov (United States)

    Chang, Darby Tien-Hau; Chen, Chien-Yu; Chung, Wen-Chin; Oyang, Yen-Jen; Juan, Hsueh-Fen; Huang, Hsuan-Cheng

    2004-01-01

    Analysis of protein–ligand interactions is a fundamental issue in drug design. As the detailed and accurate analysis of protein–ligand interactions involves calculation of binding free energy based on thermodynamics and even quantum mechanics, which is highly expensive in terms of computing time, conformational and structural analysis of proteins and ligands has been widely employed as a screening process in computer-aided drug design. In this paper, a web server called ProteMiner-SSM designed for efficient analysis of similar protein tertiary substructures is presented. In one experiment reported in this paper, the web server has been exploited to obtain some clues about a biochemical hypothesis. The main distinction in the software design of the web server is the filtering process incorporated to expedite the analysis. The filtering process extracts the residues located in the caves of the protein tertiary structure for analysis and operates with O(nlogn) time complexity, where n is the number of residues in the protein. In comparison, the α-hull algorithm, which is a widely used algorithm in computer graphics for identifying those instances that are on the contour of a three-dimensional object, features O(n2) time complexity. Experimental results show that the filtering process presented in this paper is able to speed up the analysis by a factor ranging from 3.15 to 9.37 times. The ProteMiner-SSM web server can be found at http://proteminer.csie.ntu.edu.tw/. There is a mirror site at http://p4.sbl.bc.sinica.edu.tw/proteminer/. PMID:15215355

  18. Strong lensing signatures of luminous structure and substructure in early-type galaxies

    Science.gov (United States)

    Gilman, Daniel; Agnello, Adriano; Treu, Tommaso; Keeton, Charles R.; Nierenberg, Anna M.

    2017-01-01

    The arrival times, positions, and fluxes of multiple images in strong lens systems can be used to infer the presence of dark subhalos in the deflector, and thus test predictions of cold dark matter models. However, gravitational lensing does not distinguish between perturbations to a smooth gravitational potential arising from baryonic and non-baryonic mass. In this work, we quantify the extent to which the stellar mass distribution of a deflector can reproduce flux ratio and astrometric anomalies typically associated with the presence of a dark matter subhalo. Using Hubble Space Telescope images of nearby galaxies, we simulate strong lens systems with real distributions of stellar mass as they would be observed at redshift zd = 0.5. We add a dark matter halo and external shear to account for the smooth dark matter field, omitting dark substructure, and use a Monte Carlo procedure to characterize the distributions of image positions, time delays, and flux ratios for a compact background source of diameter 5 pc. By convolving high-resolution images of real galaxies with a Gaussian PSF, we simulate the most detailed smooth potential one could construct given high quality data, and find scatter in flux ratios of ≈10%, which we interpret as a typical deviation from a smooth potential caused by large and small scale structure in the lensing galaxy. We demonstrate that the flux ratio anomalies arising from galaxy-scale baryonic structure can be minimized by selecting the most massive and round deflectors, and by simultaneously modeling flux ratio and astrometric data.

  19. The Extended Halo of Centaurus A: Uncovering Satellites, Streams, and Substructures

    Science.gov (United States)

    Crnojević, D.; Sand, D. J.; Spekkens, K.; Caldwell, N.; Guhathakurta, P.; McLeod, B.; Seth, A.; Simon, J. D.; Strader, J.; Toloba, E.

    2016-05-01

    We present the widest-field resolved stellar map to date of the closest (D˜ 3.8 Mpc) massive elliptical galaxy NGC 5128 (Centaurus A; Cen A), extending out to a projected galactocentric radius of ˜150 kpc. The data set is part of our ongoing Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS) utilizing the Magellan/Megacam imager. We resolve a population of old red giant branch (RGB) stars down to ˜1.5 mag below the tip of the RGB, reaching surface brightness limits as low as {μ }V,0˜ 32 mag arcsec-2. The resulting spatial stellar density map highlights a plethora of previously unknown streams, shells, and satellites, including the first tidally disrupting dwarf around Cen A (CenA-MM-Dw3), which underline its active accretion history. We report 13 previously unknown dwarf satellite candidates, of which 9 are confirmed to be at the distance of Cen A (the remaining 4 are not resolved into stars), with magnitudes in the range {M}V=-7.2 to -13.0, central surface brightness values of {μ }V,0=25.4{--}26.9 mag arcsec-2, and half-light radii of {r}h=0.22{--}2.92 {{kpc}}. These values are in line with Local Group dwarfs but also lie at the faint/diffuse end of their distribution; interestingly, CenA-MM-Dw3 has similar properties to the recently discovered ultradiffuse galaxies in Virgo and Coma. Most of the new dwarfs are fainter than the previously known Cen A satellites. The newly discovered dwarfs and halo substructures are discussed in light of their stellar populations, and they are compared to those discovered by the PAndAS survey of M31. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

  20. Subspace orthogonalization for substructuring preconditioners for nonsymmetric systems of linear equations

    Energy Technology Data Exchange (ETDEWEB)

    Starke, G. [Universitaet Karlsruhe (Germany)

    1994-12-31

    For nonselfadjoint elliptic boundary value problems which are preconditioned by a substructuring method, i.e., nonoverlapping domain decomposition, the author introduces and studies the concept of subspace orthogonalization. In subspace orthogonalization variants of Krylov methods the computation of inner products and vector updates, and the storage of basis elements is restricted to a (presumably small) subspace, in this case the edge and vertex unknowns with respect to the partitioning into subdomains. The author investigates subspace orthogonalization for two specific iterative algorithms, GMRES and the full orthogonalization method (FOM). This is intended to eliminate certain drawbacks of the Arnoldi-based Krylov subspace methods mentioned above. Above all, the length of the Arnoldi recurrences grows linearly with the iteration index which is therefore restricted to the number of basis elements that can be held in memory. Restarts become necessary and this often results in much slower convergence. The subspace orthogonalization methods, in contrast, require the storage of only the edge and vertex unknowns of each basis element which means that one can iterate much longer before restarts become necessary. Moreover, the computation of inner products is also restricted to the edge and vertex points which avoids the disturbance of the computational flow associated with the solution of subdomain problems. The author views subspace orthogonalization as an alternative to restarting or truncating Krylov subspace methods for nonsymmetric linear systems of equations. Instead of shortening the recurrences, one restricts them to a subset of the unknowns which has to be carefully chosen in order to be able to extend this partial solution to the entire space. The author discusses the convergence properties of these iteration schemes and its advantages compared to restarted or truncated versions of Krylov methods applied to the full preconditioned system.

  1. Lactase persistence-related genetic variant: population substructure and health outcomes.

    Science.gov (United States)

    Smith, George Davey; Lawlor, Debbie A; Timpson, Nic J; Baban, Jamil; Kiessling, Matt; Day, Ian N M; Ebrahim, Shah

    2009-03-01

    Lactase persistence is an autosomal-dominant trait that is common in European-derived populations. A basic tendency for lactase persistence to increase from the southeast to the northwest across European populations has been noted, but such trends within countries have not been extensively studied. We genotyped the C/T(-13910) variant (rs4988235) that constitutes the putatively causal allele for lactase persistence (T allele representing persistence) in a general population sample of 3344 women aged 60-79 years from 23 towns across Britain. We found an overall frequency of 0.253 for the C (lactase non-persistence) allele, but with considerable gradients of decreasing frequency from the south to the north and from the east to the west of Britain for this allele. Daily sunlight was positively related to C (non-persistence) allele prevalence. However, sunlight exposure and latitude are strongly correlated, and it was not possible to identify which is the primary factor statistically underlying the distribution of lactase persistence. The C/T(-13910) variant (rs4988235) was not related to drinking milk or bone health (although drinking milk itself was protective of bone health), and was essentially unrelated to a wide range of other lifestyle, health and demographic characteristics. One exception was general health being rated as being poor or fair, for which there was an odds ratio of 1.38 (1.04, 1.84) for women homozygous for the C allele; on adjustment for latitude and longitude of place of birth, this attenuated to 1.19 (0.87, 1.64). The lactase persistence variant could contribute to the examination of data for the existence of, and then statistical control for, population substructure in genetic association studies.

  2. Assessment of First- and Second-Order Wave-Excitation Load Models for Cylindrical Substructures

    Energy Technology Data Exchange (ETDEWEB)

    Pereyra, Brandon; Wendt, Fabian; Robertson, Amy; Jonkman, Jason

    2016-07-01

    The hydrodynamic loads on an offshore wind turbine's support structure present unique engineering challenges for offshore wind. Two typical approaches used for modeling these hydrodynamic loads are potential flow (PF) and strip theory (ST), the latter via Morison's equation. This study examines the first- and second-order wave-excitation surge forces on a fixed cylinder in regular waves computed by the PF and ST approaches to (1) verify their numerical implementations in HydroDyn and (2) understand when the ST approach breaks down. The numerical implementation of PF and ST in HydroDyn, a hydrodynamic time-domain solver implemented as a module in the FAST wind turbine engineering tool, was verified by showing the consistency in the first- and second-order force output between the two methods across a range of wave frequencies. ST is known to be invalid at high frequencies, and this study investigates where the ST solution diverges from the PF solution. Regular waves across a range of frequencies were run in HydroDyn for a monopile substructure. As expected, the solutions for the first-order (linear) wave-excitation loads resulting from these regular waves are similar for PF and ST when the diameter of the cylinder is small compared to the length of the waves (generally when the diameter-to-wavelength ratio is less than 0.2). The same finding applies to the solutions for second-order wave-excitation loads, but for much smaller diameter-to-wavelength ratios (based on wavelengths of first-order waves).

  3. Weak lensing study of 16 DAFT/FADA clusters: Substructures and filaments

    Science.gov (United States)

    Martinet, Nicolas; Clowe, Douglas; Durret, Florence; Adami, Christophe; Acebrón, Ana; Hernandez-García, Lorena; Márquez, Isabel; Guennou, Loic; Sarron, Florian; Ulmer, Mel

    2016-05-01

    While our current cosmological model places galaxy clusters at the nodes of a filament network (the cosmic web), we still struggle to detect these filaments at high redshifts. We perform a weak lensing study for a sample of 16 massive, medium-high redshift (0.4 detection with noise resampling techniques. Taking advantage of the large field of view of our data, we study cluster environment, adding information from galaxy density maps at the cluster redshift and from X-ray images when available. We find that clusters show a large variety of weak lensing maps at large scales and that they may all be embedded in filamentary structures at megaparsec scale. We classify these clusters in three categories according to the smoothness of their weak lensing contours and to the amount of substructures: relaxed (~7%), past mergers (~21.5%), and recent or present mergers (~71.5%). The fraction of clusters undergoing merging events observationally supports the hierarchical scenario of cluster growth, and implies that massive clusters are strongly evolving at the studied redshifts. Finally, we report the detection of unusually elongated structures in CLJ0152, MACSJ0454, MACSJ0717, A851, BMW1226, MACSJ1621, and MS1621. This study is based on observations obtained with MegaCam, a joint project of CFHT and CEA/IRFU, at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. The study is also based on archive data collected at the Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. This research made use of data obtained from the Chandra Data Archive provided by the Chandra X-ray Center (CXC) and data obtained from the XMM-Newton Data Archive provided by the XMM-Newton Science Archive (XSA).

  4. Excitation Methods for Bridge Structures

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-02-08

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

  5. Balanced bridge feedback control system

    Science.gov (United States)

    Lurie, Boris J. (Inventor)

    1990-01-01

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

  6. Optimum selection on bridge erection with floating crane in East China Sea Bridge and Hangzhou Bay Bridge

    Institute of Scientific and Technical Information of China (English)

    Shunquan Qin; Pu Zhou; Youheng Hua

    2004-01-01

    @@ Introduction With the rapid development of China′s economy, many bridges will be built over the Chinese coastal waters of Pacific Ocean. Among them, construction of East China Sea Bridge has been commenced in June 2001, and will be completed at the end of 2005, Hangzhou Bay Bridge was also started to construct in June 2003(Fig. 1). These two ultralong bridges are designed as twin expressway bridges standing side by side each carries a 3-lane one-way carriageway. The total width is 31.5m and 33.0m respectively. East China Sea Bridge starts from Nanhui District, Shanghai and extends to the Yangshan Deep Water Port Area, which is located at one of the Qiqu Islands. The total length of the bridge is about 31.0 km, in which 25 km are on the sea, and 22 km is in the unnavigable region. Hangzhou Bay Bridge across the mouth of Qiantang River.

  7. Is myocardial bridging a bridge connecting to cardiovascular events?

    Institute of Scientific and Technical Information of China (English)

    LI Jian-jun

    2010-01-01

    @@ Coronary arteries and their major branches usually course on the surface of the heart in the subepicardial tissue. However, a muscle hber overlying the intramyocardial segment of an epicardial coronary artery was defined as myocardial bridging (MB), and subsequently the artery coursing within the myocardium is called a tunneled artery.

  8. Numerical Simulation of Hysteretic Live Load Effect in a Soil-Steel Bridge

    Directory of Open Access Journals (Sweden)

    Sobótka Maciej

    2014-03-01

    Full Text Available The paper presents numerical simulation of hysteretic live load effect in a soil-steel bridge. The effect was originally identified experimentally by Machelski [1], [2]. The truck was crossing the bridge one way and the other in the full-scale test performed. At the same time, displacements and stress in the shell were measured. The major conclusion from the research was that the measured quantities formed hysteretic loops. A numerical simulation of that effect is addressed in the present work. The analysis was performed using Flac finite difference code. The methodology of solving the mechanical problems implemented in Flac enables us to solve the problem concerning a sequence of load and non-linear mechanical behaviour of the structure. The numerical model incorporates linear elastic constitutive relations for the soil backfill, for the steel shell and the sheet piles, being a flexible substructure for the shell. Contact zone between the shell and the soil backfill is assumed to reflect elastic-plastic constitutive model. Maximum shear stress in contact zone is limited by the Coulomb condition. The plastic flow rule is described by dilation angle ψ = 0. The obtained results of numerical analysis are in fair agreement with the experimental evidence. The primary finding from the performed simulation is that the slip in the interface can be considered an explanation of the hysteresis occurrence in the charts of displacement and stress in the shell.

  9. Internet-based collaborative pseudo-dynamic testing of multi-span bridge structure

    Institute of Scientific and Technical Information of China (English)

    Dapeng Wang; Shizhu Tian; Xinjiang Cai; Yunlei Fan; Yan Xiao

    2009-01-01

    In this paper,the first Internet-based collaborative pseudo-dynamic testing of a multi-span bridge system in mainland China is presented in detail,which has been carried out by the collaboration of Hunan University (HNU),Harbin Institute of Technology (HIT) and Tsinghua University (TU) in mainland China,and the University of Southern California (USC) in the USA.The prototype system of Russion River Bridge at Southern California in America is illustrated.Different testing specimens,testing equipments and substructure boundary conditions at HNU and HIT laboratories are described.A network protocol platform for collaborative pseudo-dynamic testing,called NetSLab,and some function modules developed on the use of its standardized interface are introduced.Aiming at the MTS system widely used in structural testing,two approaches are presented to implement the communication interface between NetSLab and testing equipment,respectively,studied by HNU and HIT.The integrated networked testing system and collaborative testing procedures are presented.The testing results manifest that the networked collaborative testing system with powerful capability provides a testing platform with good coordination for complex models or actual structures,and achieves remote sharing of testing equipments.(C) 2009 National Natural Science Foundation of China and Chinese Academy of Sciences.Published by Elsevier Limited and Science inChina Press.All rights reserved.

  10. Architectural engineering of FRP bridges

    OpenAIRE

    Smits, J.E.P.

    2014-01-01

    This paper deals with the use of Fibre Reinforced Polymers (FRP's) in architectural and structural bridge design. The challenges and opportunities that come with this relatively new material are discussed. An inventory is made of recent engineers' solutions in FRP, followed by a discussion on architectural application of FRP's derived from the authors architectural practice.

  11. Bridge Aesthetics and Structural Honesty

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1999-01-01

    In bridges the overall form must be chosen with due respect to the transmission of forces if efficient structures shall be created, The design must therefore be governed by experienced structural engineers - in some cases assisted by aesthetic advisers on specific issues. Some basic requirements...

  12. Intercellular bridges in vertebrate gastrulation.

    Directory of Open Access Journals (Sweden)

    Luca Caneparo

    Full Text Available The developing zebrafish embryo has been the subject of many studies of regional patterning, stereotypical cell movements and changes in cell shape. To better study the morphological features of cells during gastrulation, we generated mosaic embryos expressing membrane attached Dendra2 to highlight cellular boundaries. We find that intercellular bridges join a significant fraction of epiblast cells in the zebrafish embryo, reaching several cell diameters in length and spanning across different regions of the developing embryos. These intercellular bridges are distinct from the cellular protrusions previously reported as extending from hypoblast cells (1-2 cellular diameters in length or epiblast cells (which were shorter. Most of the intercellular bridges were formed at pre-gastrula stages by the daughters of a dividing cell maintaining a membrane tether as they move apart after mitosis. These intercellular bridges persist during gastrulation and can mediate the transfer of proteins between distant cells. These findings reveal a surprising feature of the cellular landscape in zebrafish embryos and open new possibilities for cell-cell communication during gastrulation, with implications for modeling, cellular mechanics, and morphogenetic signaling.

  13. Noise Considerations in Resistance Bridges

    DEFF Research Database (Denmark)

    Diamond, Joseph M.

    1963-01-01

    A signal-to-noise analysis is made of the Wheatstone bridge, where the unknown and standard resistors may be at different temperatures, a situation which occurs in resistance thermometry. The limiting condition is assumed to be dissipation in the unknown resistor. It is shown that the ratio arms ...

  14. The Wien Bridge Oscillator Family

    DEFF Research Database (Denmark)

    Lindberg, Erik

    2006-01-01

    A tutorial in which the Wien bridge family of oscillators is defined and investigated. Oscillators which do not fit into the Barkhausen criterion topology may be designed. A design procedure based on initial complex pole quality factor is reported. The dynamic transfer characteristic...

  15. Architectural engineering of FRP bridges

    NARCIS (Netherlands)

    Smits, J.E.P.

    2014-01-01

    This paper deals with the use of Fibre Reinforced Polymers (FRP's) in architectural and structural bridge design. The challenges and opportunities that come with this relatively new material are discussed. An inventory is made of recent engineers' solutions in FRP, followed by a discussion on archit

  16. 一种针对有机分子的新式子结构匹配法——树状结构数据匹配%A Novel Substructure Match Method-Tree-Data Matching

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    提出一种针对有机分子的新的子结构匹配方法, 子结构采用树状结构数据表示,方法简单灵活,匹配快速准确。%A novel substructure match method is developed in our group. Tree-data is introduced to express substructure, which make substructure match simple,quick and flexible.

  17. History of cable-stayed bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1999-01-01

    The principle of supporting a bridge deck by inclined tension members leading to towers on either side of the span has been known for centuries. However, the real development of cable-stayed bridges did not begin before the 1950s. Since then the free span has been increased from 183 m...... in the Strömsund Bridge (from 1955) to 890 m in the Tatara Bridge (from 1999)....

  18. Dynamic analysis of structures with elastomers using substructuring with non-matched interfaces and improved modeling of elastomer properties

    Science.gov (United States)

    Lin, Hejie

    A variety of engineering structures are composed of linear structural components connected by elastomers. The components are commonly analyzed using large-scale finite element models. Examples include engine crankshafts with torsional dampers, engine structures with an elastomeric gasket between the head and the block, engine-vehicle structures using elastomeric engine mounts, etc. An analytical method is presented in this research for the dynamic analysis of large-scale structures with elastomers. The dissertation has two major parts. In the first part, a computationally efficient substructuring method is developed for substructures with non-matched interface meshes. The method is based on the conventional fixed-interface, Craig-Bampton component mode synthesis (CMS) method. However, its computational efficiency is greatly enhanced with the introduction of interface modes. Kriging interpolation at the interfaces between substructures ensures compatibility of deformation. In the second part, a series of dynamic measurements of mechanical properties of elastomers is presented. Dynamic stiffness as a function of frequency under controlled temperature and vibrational amplitude is measured. Also, the strain and stress relaxation behavior is tested to investigate the linearity and histeresis of an elastomer. The linearity of dynamic stiffness is studied and discussed in detail through the strain and stress relaxation test. The dynamic stiffness of elastomers is measured at different conditions such as temperature, frequency, and amplitude. The relationships between dynamic stiffness and temperature, and frequency and amplitude are discussed. After the dynamic properties of an elastomer are measured, a mathematical model is presented for characterizing the frequency and temperature-dependent properties of elastomers from the fundamental features of the molecular chains forming them. Experimental observations are used in the model development to greatly enhance the

  19. A two-dimensional Riemann solver with self-similar sub-structure - Alternative formulation based on least squares projection

    Science.gov (United States)

    Balsara, Dinshaw S.; Vides, Jeaniffer; Gurski, Katharine; Nkonga, Boniface; Dumbser, Michael; Garain, Sudip; Audit, Edouard

    2016-01-01

    Just as the quality of a one-dimensional approximate Riemann solver is improved by the inclusion of internal sub-structure, the quality of a multidimensional Riemann solver is also similarly improved. Such multidimensional Riemann problems arise when multiple states come together at the vertex of a mesh. The interaction of the resulting one-dimensional Riemann problems gives rise to a strongly-interacting state. We wish to endow this strongly-interacting state with physically-motivated sub-structure. The self-similar formulation of Balsara [16] proves especially useful for this purpose. While that work is based on a Galerkin projection, in this paper we present an analogous self-similar formulation that is based on a different interpretation. In the present formulation, we interpret the shock jumps at the boundary of the strongly-interacting state quite literally. The enforcement of the shock jump conditions is done with a least squares projection (Vides, Nkonga and Audit [67]). With that interpretation, we again show that the multidimensional Riemann solver can be endowed with sub-structure. However, we find that the most efficient implementation arises when we use a flux vector splitting and a least squares projection. An alternative formulation that is based on the full characteristic matrices is also presented. The multidimensional Riemann solvers that are demonstrated here use one-dimensional HLLC Riemann solvers as building blocks. Several stringent test problems drawn from hydrodynamics and MHD are presented to show that the method works. Results from structured and unstructured meshes demonstrate the versatility of our method. The reader is also invited to watch a video introduction to multidimensional Riemann solvers on http://www.nd.edu/~dbalsara/Numerical-PDE-Course.

  20. Building Bridges One Line at a Time

    Science.gov (United States)

    Grigsby, Cathy Murray

    2012-01-01

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

  1. Comparison between Modern Violin Bridge and Baroque Violin Bridge by Photoelastic Observation and Frequency Analysis

    Science.gov (United States)

    Matsutani, Akihiro

    2004-05-01

    A comparison between the modern bridge and the baroque bridge of the violin by photoelastic observation was carried out. The relationship between the stress part and the hole is symmetric in the modern and baroque bridges. The measured spectral envelopes of baroque bridges are similar to those of modern bridges in D- or G-strings, and have peaks at a frequency higher than those of modern bridges in E-string. The visualization method as used in this study may provide hints for the design of violin bridges.

  2. Reduction of fatigue loads on jacket substructure through blade design optimization for multimegawatt wind turbines at 50 m water depths

    DEFF Research Database (Denmark)

    NJOMO WANDJI, Wilfried; Pavese, Christian; Natarajan, Anand;

    2016-01-01

    This paper addresses the reduction of the fore-aft damage equivalent moment at the tower base for multi-megawatt offshore wind turbines mounted on jacket type substructures at 50 m water depths. The study investigates blade design optimization of a reference 10 MW wind turbine under standard wind...... conditions of onshore sites. The blade geometry and structure is optimized to yield a design that minimizes tower base fatigue loads without significant loss of power production compared to that of the reference setup. The resulting blade design is then mounted on a turbine supported by a jacket and placed...

  3. Effect of the shades of background substructures on the overall color of zirconia-based all-ceramic crowns

    OpenAIRE

    Suputtamongkol, Kallaya; Tulapornchai, Chantana; Mamani, Jatuphol; Kamchatphai, Wannaporn; Thongpun, Noparat

    2013-01-01

    PURPOSE The objective of this study was to determine the effect of the color of a background substructure on the overall color of a zirconia-based all-ceramic crown. MATERIALS AND METHODS Twenty one posterior zirconia crowns were made for twenty subjects. Seven premolar crowns and six molar crowns were cemented onto abutments with metal post and core in the first and second group. In the third group, eight molar crowns were cemented onto abutments with a prefabricated post and composite core ...

  4. Microscopic substructure effects in potential-model descriptions of the $^{7}Be(p,\\gamma)^{8}B$ reaction

    CERN Document Server

    Escher, J; Escher, Jutta; Jennings, Byron K.

    2000-01-01

    The spectroscopic factor arises from short-range effects in the nuclear wave function. On the other hand, cross sections for external capture reactions, such as $^7$Be$(p,\\gamma)^8$B at low energies, depend primarily on the asymptotic normalization of the bound-state wave function -- a long-range property. We investigate the relationship between potential models and the full many-body problem to illustrate how microscopic substructure effects arise naturally in the relevant transition matrix element and can be (in part) accounted for by a spectroscopic factor.

  5. Mechanistic diversity of the van Leusen reaction applied to 6-ketomorphinans and synthetic potential of the resulting acrylonitrile substructures.

    Science.gov (United States)

    Schütz, Johannes; Windisch, Petra; Kristeva, Elka; Wurst, Klaus; Ongania, Karl-Hans; Horvath, Ulrike E I; Schottenberger, Herwig; Laus, Gerhard; Schmidhammer, Helmut

    2005-06-24

    Tosylmethyl isocyanide was used to convert 7,8-didehydro-6-ketomorphinans to 6,7-didehydromorphinan-6-carbonitriles with retainment of the 4,5-epoxy ring. However, ring opening occurred in the presence of NaH giving 5,6,7,8-tetradehydromorphinan-6-carbonitriles. Addition of nucleophiles such as Li diisopropylamide or Grignard reagents to the acrylonitrile substructure yielded ring-opened 5,6-didehydro products. Seven products were characterized by X-ray crystal structure analysis and revealed insight into the mechanistic diversity of the van Leusen reaction.

  6. Improving shear bond strength between feldspathic porcelain and zirconia substructure with lithium disilicate glass-ceramic liner.

    Science.gov (United States)

    Wattanasirmkit, Kamolporn; Srimaneepong, Viritpon; Kanchanatawewat, Kanchana; Monmaturapoj, Naruporn; Thunyakitpisal, Pasutha; Jinawath, Supatra

    2015-01-01

    This study investigated the shear bond strength (SBS) between veneering porcelain and zirconia substructure using lithium disilicate glass-ceramic as a liner. The mineral phases and microstructures of lithium disilicate glass-ceramic at temperature range of 800-900°C were preliminarily investigated. SBSs of porcelain-veneered zirconia specimens with and without lithium disilicate glassceramic liner fired at the same temperature were determined. Results showed that SBSs of veneering porcelain and zirconia with lithium disilicate glass-ceramic liner was notably increased (pporcelain and zirconia.

  7. Assessing the Importance of Nonlinearities in the Development of a Substructure Model for the Wind Turbine CAE Tool FAST: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Damiani, R.; Jonkman, J.; Robertson, A.; Song, H.

    2013-03-01

    Design and analysis of wind turbines are performed using aero-servo-elastic tools that account for the nonlinear coupling between aerodynamics, controls, and structural response. The NREL-developed computer-aided engineering (CAE) tool FAST also resolves the hydrodynamics of fixed-bottom structures and floating platforms for offshore wind applications. This paper outlines the implementation of a structural-dynamics module (SubDyn) for offshore wind turbines with space-frame substructures into the current FAST framework, and focuses on the initial assessment of the importance of structural nonlinearities. Nonlinear effects include: large displacements, axial shortening due to bending, cross-sectional transverse shear effects, etc.

  8. Near-Field Cosmology with RR Lyrae Variable Stars: A First View of Substructure in the Southern Sky

    Science.gov (United States)

    Navarrete, C.; Duffau, S.; Vivas, A. K.; Catelan, M.; Hajdu, G.; Torrealba, G.; Cortés, C.; Belokurov, V.; Koposov, S.; Drake, A. J.

    2016-08-01

    We present the current status of the spectroscopic follow-up of a large number of RR Lyrae (RRL) halo overdensity candidates recently found by Torrealba et al. (2015) using southern-hemisphere data from the Catalina Real-time Transient Survey (CRTS). Characterizing the individual RRL stars in these overdensities is crucial to confirm them as real halo substructures. Low-resolution spectra have been obtained for RRL stars in 11 different overdensities, using the SOAR and Magellan telescopes. Radial velocities and metallicities have been derived so far for 123 and 99 RRL stars, respectively.

  9. Beginning Course Surveys: Bridges for Knowing and Bridges for Being

    Directory of Open Access Journals (Sweden)

    David Starr-Glass

    2011-06-01

    Full Text Available The use of a participant survey, administered at the outset of an online course, can provide information useful in the management of the learning environment and in its subsequent redesign. Such information can clarify participants’ prior experience, expectations, and demographics. But the very act of enquiring about the learner also signals the instructor’s social presence, relational interest, and desire to enter into an authentic dialogue. This study examines the use of participant surveys in online management courses. The first section discusses the informational bridges that this instrument provides. The second section considers survey responses to open-ended questions dealing with student sentiments. This analysis suggests that the survey plays a valuable part in accentuating social presence and in initiating relational bridges with participants.

  10. ESTIMATION OF ECONOMIC EXPEDIENCY OF «BRIDGE-PRE-BRIDGE TERRITORY» SYSTEM

    Directory of Open Access Journals (Sweden)

    A. A. Lapko

    2008-01-01

    Full Text Available The paper considers principles that form «Bridge-Pre-Bridge Territory» system. The method is proposed for calculation of expenses on technical research for development of projects on usage of pre-bridge territories. Usage of site class number for natural conditions makes it possible to estimate investment attractiveness of «Bridge-Pre-Bridge Territory» system.

  11. 33 CFR 115.70 - Advance approval of bridges.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Advance approval of bridges. 115... BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE PROCEDURES § 115.70 Advance approval of bridges. (a) The General Bridge Act of 1946 requires the approval of the location and plans of bridges...

  12. Performance analysis of LAN bridges and routers

    Science.gov (United States)

    Hajare, Ankur R.

    1991-01-01

    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.

  13. Problems associated with nondestructive evaluation of bridges

    Science.gov (United States)

    Prine, David W.

    1995-05-01

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

  14. Correlation between the sub-structure parameters and the manufacturing technologies of metal threads in historical textiles using X-ray line profile analysis

    Science.gov (United States)

    Csiszár, Gábor; Ungár, Tamás; Járó, Márta

    2013-06-01

    Micro-structure can talk when documentation is missing. In ancient Roman or medieval periods, kings, queens, or just rich people decorated their clothes or even their horse covers richly with miniature jewels or metal threads. The origin or the fabrication techniques of these ancient threads is often unknown. Thirteen thread samples made of gold or gilt silver manufactured during the last sixteen hundred years are investigated for the micro-structure in terms of dislocation density, crystallite size, and planar defects. In a few cases, these features are compared with sub-structure of similar metallic threads prepared in modern, twentieth century workshops. The sub-structure is determined by X-ray line profile analysis, using high resolution diffractograms with negligible instrumental broadening. On the basis of the sub-structure parameters, we attempt to assess the metal-threads manufacturing procedures on samples stemming from the fourth century A.D. until now.

  15. Correlation between the sub-structure parameters and the manufacturing technologies of metal threads in historical textiles using X-ray line profile analysis

    Energy Technology Data Exchange (ETDEWEB)

    Csiszar, Gabor; Ungar, Tamas [Eoetvoes University Budapest, Department of Materials Physics, Budapest (Hungary); Jaro, Marta [Hungarian National Museum, Budapest (Hungary)

    2013-06-15

    Micro-structure can talk when documentation is missing. In ancient Roman or medieval periods, kings, queens, or just rich people decorated their clothes or even their horse covers richly with miniature jewels or metal threads. The origin or the fabrication techniques of these ancient threads is often unknown. Thirteen thread samples made of gold or gilt silver manufactured during the last sixteen hundred years are investigated for the micro-structure in terms of dislocation density, crystallite size, and planar defects. In a few cases, these features are compared with sub-structure of similar metallic threads prepared in modern, twentieth century workshops. The sub-structure is determined by X-ray line profile analysis, using high resolution diffractograms with negligible instrumental broadening. On the basis of the sub-structure parameters, we attempt to assess the metal-threads manufacturing procedures on samples stemming from the fourth century A.D. until now. (orig.)

  16. Exploring the Variable Sky with LINEAR. II. Halo Structure and Substructure Traced by RR Lyrae Stars to 30 kpc

    CERN Document Server

    Sesar, Branimir; Stuart, J Scott; Morgan, Dylan M; Becker, Andrew C; Sharma, Sanjib; Palaversa, Lovro; Jurić, Mario; Wozniak, Przemyslaw; Oluseyi, Hakeem

    2013-01-01

    We present a sample of ~5,000 RR Lyrae stars selected from the recalibrated LINEAR dataset and detected at heliocentric distances between 5 kpc and 30 kpc over ~8,000 deg^2 of sky. The coordinates and light curve properties, such as period and Oosterhoff type, are made publicly available. We find evidence for the Oosterhoff dichotomy among field RR Lyrae stars, with the ratio of the type II and I subsamples of about 1:4. The number density distribution of halo RRab stars as a function of galactocentric distance can be described as an oblate ellipsoid with the axis ratio q=0.63 and with either a single or a double power law with a power-law index in the range -2 to -3. Using a group-finding algorithm EnLink, we detected seven candidate halo groups, only one of which is statistically spurious. Three of these groups are near globular clusters (M53/NGC 5053, M3, M13), and one is near a known halo substructure (Virgo Stellar Stream); the remaining three groups do not seem to be near any known halo substructures or...

  17. The Bolocam Galactic Plane Survey. XI. Temperatures and Substructure of Galactic Clumps Based on 350 micron Observations

    CERN Document Server

    Merello, Manuel; Shirley, Yancy L; Rosolowsky, Erik; Ginsburg, Adam; Bally, John; Battersby, Cara; Dunham, Michael M

    2015-01-01

    We present 107 maps of continuum emission at 350 microns from Galactic molecular clumps. Observed sources were mainly selected from the Bolocam Galactic Plane Survey (BGPS) catalog, with 3 additional maps covering star forming regions in the outer Galaxy. The higher resolution of the SHARC-II images (8.5'' beam) compared with the 1.1 mm images from BGPS (33'' beam) allowed us to identify a large population of smaller substructures within the clumps. A catalog is presented for the 1386 sources extracted from the 350 micron maps. The color temperature distribution of clumps based on the two wavelengths has a median of 13.3 K and mean of 16.3 +- 0.4 K, assuming an opacity law index of 1.7. For the structures with the best determined color temperatures, the mean ratio of gas temperature, determined from NH3 observations, to dust color temperature is 0.88 and the median ratio is 0.76. About half the clumps have more than two substructures and 22 clumps have more than 10. The fraction of the mass in dense substruct...

  18. New Structural-Dynamics Module for Offshore Multimember Substructures within the Wind Turbine Computer-Aided Engineering Tool FAST: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Song, H.; Damiani, R.; Robertson, A.; Jonkman, J.

    2013-08-01

    FAST, developed by the National Renewable Energy Laboratory (NREL), is a computer-aided engineering (CAE) tool for aero-hydro-servo-elastic analysis of land-based and offshore wind turbines. This paper discusses recent upgrades made to FAST to enable loads simulations of offshore wind turbines with fixed-bottom, multimember support structures (e.g., jackets and tripods, which are commonly used in transitional-depth waters). The main theory and strategies for the implementation of the multimember substructure dynamics module (SubDyn) within the new FAST modularization framework are introduced. SubDyn relies on two main engineering schematizations: 1) a linear frame finite-element beam (LFEB) model and 2) a dynamics system reduction via Craig-Bampton's method. A jacket support structure and an offshore system consisting of a turbine atop a jacket substructure were simulated to test the SubDyn module and to preliminarily assess results against results from a commercial finite-element code.

  19. Sub-structures formed in the excited state are responsible for tryptophan residues fluorescence in β-lactoglobulin.

    Science.gov (United States)

    Albani, Jihad-Rene

    2011-07-01

    Origin of tryptophan residues fluorescence in β-lactoglobulin is analyzed. Fluorescence lifetimes and spectra of β-lactoglobulin solution are measured at pH going from 2 to 12 and in 6 M guanidine. Tryptophan residues emit with three lifetimes at all conditions. Two lifetimes (0.4-0.5 ns and 2-4 ns) are in the same range of those measured for tryptophan free in solution. Lifetimes in the denatured states are lower than those measured in the native state. Pre-exponential values are modified with the protein structure. Data are identical to those already obtained for other proteins. Fluorescence lifetimes characterize internal states of the tryptophan residues (Tryptophan sub-structures) independently of the tryptophan environments, the third lifetime results from the interaction that is occurring between the Trp residues and its environment. Pre-exponential values characterize substructures populations. In conclusion, tryptophan mission occurs from substates generated in the excited state. This is in good agreement with the theory we described in recent works.

  20. CLASH-VLT: Substructure in the galaxy cluster MACS J1206.2-0847 from kinematics of galaxy populations

    CERN Document Server

    Girardi, M; Balestra, I; Nonino, M; Biviano, A; Grillo, C; Rosati, P; Annunziatella, M; Demarco, R; Fritz, A; Gobat, R; Lemze, D; Presotto, V; Scodeggio, M; Tozzi, P; Caminha, G Bartosch; Brescia, M; Coe, D; Kelson, D; Koekemoer, A; Lombardi, M; Medezinski, E; Postman, M; Sartoris, B; Umetsu, K; Zitrin, A; Boschin, W; Czoske, O; De Lucia, G; Kuchner, U; Maier, C; Meneghetti, M; Monaco, P; Monna, A; Munari, E; Seitz, S; Verdugo, M; Ziegler, B

    2015-01-01

    In the effort to understand the link between the structure of galaxy clusters and their galaxy populations, we focus on MACS J1206.2-0847, at z~0.44, probing its substructure in the projected phase space through the spectrophotometric properties of a large number of galaxies from the CLASH-VLT survey. Our analysis is mainly based on an extensive spectroscopic dataset of 445 member galaxies, mostly acquired with VIMOS@VLT as part of our ESO Large Programme, sampling the cluster out to a radius ~2R200 (4 Mpc). We classify 412 galaxies as: passive, with strong Hdelta absorption (red and blue ones), and with emission lines from weak to very strong ones. A number of tests for substructure detection is applied to analyze the galaxy distribution in the velocity space, in the 2D space, and in the (3D) projected phase-space. Studied in its entirety, the cluster appears as a large-scale relaxed system with a few, secondary, minor overdensities in 2D distribution. We detect no velocity gradient or evidence of deviations...

  1. MUSTANG High Angular Resolution Sunyaev-Zel'dovich Effect Imaging of Sub-Structure in Four Galaxy Clusters

    CERN Document Server

    Korngut, P M; Reese, E D; Mason, B S; Devlin, M J; Mroczkowski, T; Sarazin, C L; Sun, M; Sievers, J

    2010-01-01

    We present 10" to 18" images of four massive clusters of galaxies through the Sunyaev-Zel'dovich Effect (SZE). These measurements, made at 90~GHz with the MUSTANG receiver on the Green Bank Telescope (GBT), reveal pressure sub-structure to the intra-cluster medium (ICM) in three of the four systems. We identify the likely presence of a previously unknown weak shock-front in MACS0744+3927. By fitting the Rankine-Hugoniot density jump conditions in a complementary SZE/X-ray analysis, we infer a Mach number of M = 1.2^{+0.2}_{-0.2} and a shock-velocity of 1827^{+267}_{-195}~km/s. In RXJ1347-1145, we present a new reduction of previously reported data and confirm the presence of a south-east SZE enhancement with a significance of 13.9 sigma when smoothed to 18" resolution. This too is likely caused by shock-heated gas produced in a recent merger. In our highest redshift system, CL1226+3332, we detect sub-structure at a peak significance of 4.6 sigma in the form of a ridge oriented orthogonally to the vector conne...

  2. Parabolic metamaterials and Dirac bridges

    Science.gov (United States)

    Colquitt, D. J.; Movchan, N. V.; Movchan, A. B.

    2016-10-01

    A new class of multi-scale structures, referred to as `parabolic metamaterials' is introduced and studied in this paper. For an elastic two-dimensional triangular lattice, we identify dynamic regimes, which corresponds to so-called `Dirac Bridges' on the dispersion surfaces. Such regimes lead to a highly localised and focussed unidirectional beam when the lattice is excited. We also show that the flexural rigidities of elastic ligaments are essential in establishing the `parabolic metamaterial' regimes.

  3. Severe ASR damaged concrete bridges

    DEFF Research Database (Denmark)

    Antonio Barbosa, Ricardo; Gustenhoff Hansen, Søren

    2015-01-01

    Technical University of Denmark (DTU) and University of Southern Denmark (SDU) have conducted several full-scale experiments with severe ASR deteriorated bridges. This paper presents few and preliminary results from both the shear tests and the measuring of the material properties. The shear test...... show that the shear capacity is almost unaffected of ASR despite significant reduction in compressive concrete strength. Furthermore, measurements show a significant tensile reinforcement strain developed due to ASR expansion....

  4. Inspection Strategies for Concrete Bridges

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    1989-01-01

    In this paper an optimal inspection strategy for concrete bridges based on periodic routine and detailed inspections is presented. The failure mode considered is corrosion of the reinforcement due to chlorides. A simple modelling of the corrosion and of the inspection strategy is presented....... The optimal inspection strategy is determined from an optimization problem, where the design variables are time intervals between detailed inspections and the concrete cover. The strategy is illustrated on a simple structure, namely a reinforced concrete beam....

  5. Cochleates bridged by drug molecules.

    Science.gov (United States)

    Syed, Uwais M; Woo, Amy F; Plakogiannis, Fotios; Jin, Tuo; Zhu, Hua

    2008-11-03

    A new type of cochleate, able to microencapsulate water-soluble cationic drugs or peptides into its inter-lipid bi-layer space, was formed through interaction between negatively charged lipids and drugs or peptides acting as the inter-bi-layer bridges instead of multi-cationic metal ions. This new type of cochleate opened up to form large liposomes when treated with EDTA, suggesting that cationic organic molecules can be extracted from these cochleates in a way similar to multivalent metal ions from metal ion-bridged cochleates. Cochleates can be produced in sub-micron size using a method known as "hydrogel isolated cochleation" or simply by increasing the ratio of multivalent cationic peptides over negatively charged liposomes. When nanometer-sized cochleates and liposomes containing the same fluorescent labeled lipid component were incubated with human fibroblasts cells under identical conditions, cells exposed to cochleates showed bright fluorescent cell surfaces, whereas those incubated with liposomes did not. This result suggests that cochleates' edges made them fuse with the cell surfaces as compared to edge free liposomes. This mechanism of cochleates' fusion with cell membrane was supported by a bactericidal activity assay using tobramycin cochleates, which act by inhibiting intracellular ribosomes. Tobramycin bridged cochleates in nanometer size showed improved antibacterial activity than the drug's solution.

  6. Study of Substructure of High Transverse Momentum Jets Produced in Proton-Antiproton Collisions at sqrt(s)=1.96 TeV

    CERN Document Server

    Aaltonen, T.

    2012-01-01

    A study of the substructure of jets with transverse momentum greater than 400 GeV/c produced in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV at the Fermilab Tevatron Collider and recorded by the CDF II detector is presented. The distributions of the jet mass, angularity, and planar flow are measured for the first time in a sample with an integrated luminosity of 5.95 fb^-1. The observed substructure for high mass jets is consistent with predictions from perturbative quantum chromodynamics.

  7. The effect of a disc on the population of cuspy and cored dark matter substructures in Milky Way-like galaxies

    Science.gov (United States)

    Errani, Raphaël; Peñarrubia, Jorge; Laporte, Chervin F. P.; Gómez, Facundo A.

    2017-02-01

    We use high-resolution N-body simulations to study the effect of a galactic disc on the dynamical evolution of dark matter substructures with orbits and structural parameters extracted from the Aquarius A-2 merger tree. Satellites are modelled as equilibrium N-body realizations of generalized Hernquist profiles with 2 × 106 particles and injected in the analytical evolving host potential at zinfall, defined by the peak of their mass evolution. We select all substructures with M200(zinfall) ≥ 108 M⊙ and first pericentric distances rp values for all four models.

  8. Salt bridges: geometrically specific, designable interactions.

    Science.gov (United States)

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

    2011-03-01

    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, co-operativity in networked salt bridges, inclusion within metal-binding sites, preference for acidic electrons, apparent conformational side chain entropy reduction on 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.

  9. Evaluation method research on prestressed concrete bridges

    Institute of Scientific and Technical Information of China (English)

    HUANG Qiao; LIN Yang-zi; REN Yuan

    2008-01-01

    Considering the construction features of prestressed concrete bridge, the comprehensive evaluation method about the bridge damage conditions are studied. Particular attentions are paid on establishing a multi-level evaluation model for damaged prestressed concrete bridge, and the evaluation indices of the model as well as the rating standards are defined in the model. A normal relative function about the evaluation indices of each element is developed to calculate the relative degree, and for each element which is no sub-level elements. When evaluating the elements in sub-item level or index level of the model, the weights of elements that are pertained to one element are adopted, taking account of their deterioration degree. At the same time, the dam-age conditions of bridge are characterized by relative degree, element evaluation scale and structural technology mark of bridge ,so it agrees with Code for Maintenance of Highway Bridges and Culvers.

  10. Study on structural system of Sutong Bridge

    Institute of Scientific and Technical Information of China (English)

    Zhang Xigang; Pei Minshan; Yuan Hong; Xu Liping; Zhu Bin

    2009-01-01

    Sutong Bridge, whose layout is [ (100 + 100 + 300) + 1 088 + ( 300 + 100 + 100) ] m, marks the largest span of cable-stayed bridges in the world. The complex natural condition at the bridge site and the strict requirements for resistance of wind and seismic action make it crucial to choose a favorable structural system to assure the function and safety of the bridge. The comparison among several optional structural systems for Sutong Bridge is illustrated. After detailed analysis is carried out for viscous damper and hydraulic buffer, super liquid viscous damper with additional displacement limitation is designed for the first application in bridge engineering. The parameters for the damper is analyzed and studied and the dampers are installed suecessfuUy after quality tests.

  11. EXPLORING THE VARIABLE SKY WITH LINEAR. II. HALO STRUCTURE AND SUBSTRUCTURE TRACED BY RR LYRAE STARS TO 30 kpc

    Energy Technology Data Exchange (ETDEWEB)

    Sesar, Branimir [Division of Physics, Mathematics and Astronomy, Caltech, Pasadena, CA 91125 (United States); Ivezic, Zeljko; Morgan, Dylan M.; Becker, Andrew C. [University of Washington, Department of Astronomy, P.O. Box 351580, Seattle, WA 98195-1580 (United States); Stuart, J. Scott [Lincoln Laboratory, Massachusetts Institute of Technology, 244 Wood Street, Lexington, MA 02420-9108 (United States); Sharma, Sanjib [Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia); Palaversa, Lovro [Observatoire astronomique de l' Universite de Geneve, 51 chemin des Maillettes, CH-1290 Sauverny (Switzerland); Juric, Mario [Steward Observatory, University of Arizona, Tucson, AZ 85121 (United States); Wozniak, Przemyslaw [Los Alamos National Laboratory, 30 Bikini Atoll Rd., Los Alamos, NM 87545-0001 (United States); Oluseyi, Hakeem [Florida Institute of Technology, Melbourne, FL 32901 (United States)

    2013-08-01

    We present a sample of {approx}5000 RR Lyrae stars selected from the recalibrated LINEAR data set and detected at heliocentric distances between 5 kpc and 30 kpc over {approx}8000 deg{sup 2} of sky. The coordinates and light curve properties, such as period and Oosterhoff type, are made publicly available. We analyze in detail the light curve properties and Galactic distribution of the subset of {approx}4000 type ab RR Lyrae (RRab) stars, including a search for new halo substructures and the number density distribution as a function of Oosterhoff type. We find evidence for the Oosterhoff dichotomy among field RR Lyrae stars, with the ratio of the type II and I subsamples of about 1:4, but with a weaker separation than for globular cluster stars. The wide sky coverage and depth of this sample allow unique constraints for the number density distribution of halo RRab stars as a function of galactocentric distance: it can be described as an oblate ellipsoid with an axis ratio q = 0.63 and with either a single or a double power law with a power-law index in the range -2 to -3. Consistent with previous studies, we find that the Oosterhoff type II subsample has a steeper number density profile than the Oosterhoff type I subsample. Using the group-finding algorithm EnLink, we detected seven candidate halo groups, only one of which is statistically spurious. Three of these groups are near globular clusters (M53/NGC 5053, M3, M13), and one is near a known halo substructure (Virgo Stellar Stream); the remaining three groups do not seem to be near any known halo substructures or globular clusters and seem to have a higher ratio of Oosterhoff type II to Oosterhoff type I RRab stars than what is found in the halo. The extended morphology and the position (outside the tidal radius) of some of the groups near globular clusters are suggestive of tidal streams possibly originating from globular clusters. Spectroscopic follow-up of detected halo groups is encouraged.

  12. Analysis of liquid bridge between spherical particles

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A pair of central moving spherical particles connected by a pendular liquid bridge with interstitial Newtonian fluid is often encountered in pariculate coalescence process. In this paper, by assuming perfect-wet condition, the effects of liquid volume and separation distance on static liquid bridge are analyzed, and the relation between rupture energy and liquid bridge volume is also studied. These points would be of significance in industrial processes related to adhesive particles.

  13. Bridge Engineering-Oriented Parametric Model

    Institute of Scientific and Technical Information of China (English)

    周凌远; 李乔

    2004-01-01

    A new model is proposed to improve the efficiency of structural modeling. In this model, the bridge structural components are expressed with component description, parametric description and geometric description in a software system. This model provides both convenience and flexibility for users in structural modeling process. The object-oriented method is applied in the model implementation. A bridge analysis preprocessor is developed on the basis of this model. It provides an effective way for bridge modeling.

  14. Dynamics and Statics of Nonaxisymmetric Liquid Bridges

    Science.gov (United States)

    Alexander, J. Iwan D.; Resnick, Andrew H.; Slobozhanin, L. A.

    1996-01-01

    Theoretical and experimental investigation of the stability of nonaxisymmetric and nonaxisymmetric bridges contained between equal and unequal radii disks as a function of Bond and Weber number with emphasis on the transition from unstable axisymmetric to stable nonaxisymmetric shapes, are conducted. Numerical analysis of the stability of nonaxisymmetric bridges between unequal disks for various orientations of the gravity vector is performed. Experimental and theoretical investigation of large (nonaxisymmetric) oscillations and breaking of liquid bridges are also conducted.

  15. Mathematical Modelling of Bridges with SAP2000

    OpenAIRE

    Maraž, Miha

    2006-01-01

    The present work describes a relatively new programme module, which is enhanced in the recently released versions of SAP2000 software. The new module, called Bridge Modeler, is intended for simple, parametric mathematical modelling of bridges. The modelling procedure is explained on a test case through the steps of a user-friendly Bridge Wizard. For each step, we described the basic principles and the application possibilities as well as some limitations. We also explained two types of analys...

  16. Buddha and the bridging relations.

    Science.gov (United States)

    Banerjee, Rahul

    2008-01-01

    The chapter reviews a classical Indian model of consciousness found in the Abhidhamma, a collection of seven treatises in the Pali Canon Tipitaka. The model was based on observations made during advanced vipassana practice, a first-person method taught by the Buddha. The climax of the model consists in the elucidation of 24 'Bridging Relations' causally linking the stream of consciousness, its contents and associated physical events. Review of such a model based on a specialized first-person technique could prove to be a resource of useful ideas providing directions for further research.

  17. Family Medicine: Bridge to Life.

    Science.gov (United States)

    Luz, Clare

    2016-01-01

    Reflecting on the suicide of a close friend, this essay explores what comprises, and inspires a will to live, and how those in Family Medicine can address suicide risk even in the face of debilitating or terminal illness. Research indicates that the will to live is a measurable indicator of general well-being, distinct from depression, and an important predictor of a person's motivation to "hold on to life". As such, understanding what is at the heart of a desire to live should alter clinical practice. This essay offers ideas for ways in which to create bridges for patients that could help sustain life.

  18. Nanoclusters a bridge across disciplines

    CERN Document Server

    Jena, Purusottam

    2010-01-01

    This comprehensive book on Nanoclusters comprises sixteen authoritative chapters written by leading researchers in the field. It provides insight into topics that are currently at the cutting edge of cluster science, with the main focus on metal and metal compound systems that are of particular interest in materials science, and also on aspects related to biology and medicine. While there are numerous books on clusters, the focus on clusters as a bridge across disciplines sets this book apart from others. Delivers cutting edge coverage of cluster science Covers a broad range of topics in

  19. A bridge to advanced mathematics

    CERN Document Server

    Sentilles, Dennis

    2011-01-01

    This helpful workbook-style ""bridge"" book introduces students to the foundations of advanced mathematics, spanning the gap between a practically oriented calculus sequence and subsequent courses in algebra and analysis with a more theoretical slant. Part 1 focuses on logic and number systems, providing the most basic tools, examples, and motivation for the manner, method, and concerns of higher mathematics. Part 2 covers sets, relations, functions, infinite sets, and mathematical proofs and reasoning. Author Dennis Sentilles also discusses the history and development of mathematics as well a

  20. Review of Energy Harvesters Utilizing Bridge Vibrations

    Directory of Open Access Journals (Sweden)

    Farid Ullah Khan

    2016-01-01

    Full Text Available For health monitoring of bridges, wireless acceleration sensor nodes (WASNs are normally used. In bridge environment, several forms of energy are available for operating WASNs that include wind, solar, acoustic, and vibration energy. However, only bridge vibration has the tendency to be utilized for embedded WASNs application in bridge structures. This paper reports on the recent advancements in the area of vibration energy harvesters (VEHs utilizing bridge oscillations. The bridge vibration is narrowband (1 to 40 Hz with low acceleration levels (0.01 to 3.8 g. For utilization of bridge vibration, electromagnetic based vibration energy harvesters (EM-VEHs and piezoelectric based vibration energy harvesters (PE-VEHs have been developed. The power generation of the reported EM-VEHs is in the range from 0.7 to 1450000 μW. However, the power production by the developed PE-VEHs ranges from 0.6 to 7700 μW. The overall size of most of the bridge VEHs is quite comparable and is in mesoscale. The resonant frequencies of EM-VEHs are on the lower side (0.13 to 27 Hz in comparison to PE-VEHs (1 to 120 Hz. The power densities reported for these bridge VEHs range from 0.01 to 9539.5 μW/cm3 and are quite enough to operate most of the commercial WASNs.

  1. CONDITION RATING SYSTEM FOR THAILAND'S CONCRETE BRIDGES

    Directory of Open Access Journals (Sweden)

    Bonaventure H.W. Hadikusumo

    2010-06-01

    Full Text Available The Bridge Management System is designed to maximise use of available data and determine the optimal strategy to perform necessary improvements to bridges in the most cost-effective manner. This paper provides a condition rating system to meet the requirements of Thailand’s Department of Highways (DOH. A rating system to assess the existing condition of bridges is proposed. Segmental inspection is developed to execute efficient element-level evaluations and collect data that demonstrate deterioration patterns in bridge elements. The paper also describes inspection procedures for field survey execution, which enables observed distresses at the level of sub-elements or members to be allocated. Recommendations from bridge experts reveal that the proposed rating system is robust, implementable in actual practice, and suitable for efficient application in evaluating the nation’s concrete highway bridges. Although the bridge condition rating was developed in response to the specific characteristics of Thailand’s bridges, the proposed methodology can easily be extended to other bridge agencies.

  2. A data management infrastructure for bridge monitoring

    Science.gov (United States)

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

    2015-04-01

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

  3. Assessment of the Reliability of Concrete Bridges

    DEFF Research Database (Denmark)

    Middleton, C. R.; Thoft-Christensen, Palle

    a significant shift in emphasis for the highways authorities around the world away from the design of new structures over to maintaining the existing infrastructure. As a result, bridge owners are seeking improved ways of inspecting, assessing, maintaining and repairing their existing stock of bridges...... in the wake of ever increasing traffic loads and volumes, and an ageing population of bridges subject to various mechanisms of deterioration. The goal is to optimise the allocation of limited resources whilst maintaining their bridges in a safe and serviceable condition. Reliability analysis is one tool being...

  4. SHARP - II. Mass structure in strong lenses is not necessarily dark matter substructure: a flux ratio anomaly from an edge-on disc in B1555+375

    Science.gov (United States)

    Hsueh, J.-W.; Fassnacht, C. D.; Vegetti, S.; McKean, J. P.; Spingola, C.; Auger, M. W.; Koopmans, L. V. E.; Lagattuta, D. J.

    2016-11-01

    Gravitational lens flux-ratio anomalies provide a powerful technique for measuring dark matter substructure in distant galaxies. However, before using these flux-ratio anomalies to test galaxy formation models, it is imperative to ascertain that the given anomalies are indeed due to the presence of dark matter substructure and not due to some other component of the lensing galaxy halo or to propagation effects. Here we present the case of CLASS~B1555+375, which has a strong radio-wavelength flux-ratio anomaly. Our high-resolution near-infrared Keck~II adaptive optics imaging and archival Hubble Space Telescope data reveal the lensing galaxy in this system to have a clear edge-on disc component that crosses directly over the pair of images that exhibit the flux-ratio anomaly. We find that simple models that include the disc can reproduce the cm-wavelength flux-ratio anomaly without requiring additional dark matter substructure. Although further studies are required, our results suggest the assumption that all flux-ratio anomalies are due to a population of dark matter sub-haloes may be incorrect, and analyses that do not account for the full complexity of the lens macro-model may overestimate the substructure mass fraction in massive lensing galaxies.

  5. Analytical solutions of horizontal displacement for the dual structure consisting of flexural-shear substructures and flexural substructures%弯剪型-弯曲型双重抗侧力结构体系水平位移的解析解

    Institute of Scientific and Technical Information of China (English)

    郭猛; 牟在根; 袁泉

    2011-01-01

    对中高层弯剪型-弯曲型双重抗侧力结构体系的水平位移计算方法进行了研究.将弯曲型子结构视为仅发生弯曲变形的悬臂墙,将弯剪型子结构视为同时发生弯曲变形和剪切变形的Timoshenko悬臂墙,在此基础上建立了弯剪型-弯曲型双重抗侧力结构体系的位移微分方程,结合边界条件,推导了均布荷载等三种荷载下结构的弯曲变形、剪切变形和总水平位移的解析解.探讨了弯剪型-弯曲型双重结构与剪切形-弯曲形双重结构位移计算方法的关系.结果表明,剪切形-弯曲形双重结构可视为弯剪型-弯曲型双重结构在弯剪型子结构抗弯刚度取无穷大时的一种特殊表现形式.%A calculation method of horizontal displacement was studied for the dual structure consisting of flexural-shear substructures and flexural substructures.The flexural substructures are regarded as flexural cantilever walls which exhibit a predominantly flexural behavior,and the flexural-shear substructures are regarded as Timoshenko cantilever walls which exhibit a mixed flexural/shear behavior.On the basis of the above assumptions,a differential equation was established for calculating the displacement of the dual structure.With boundary conditions,the analytical solutions of the displacement,including the flexural deformation,the shear deformation and the total horizontal displacement,were derived when the dual structure was subjected to uniform loads.The relation between the dual structure consisting of flexural-shear substructures flexural substructures and that consisting of shear substructures flexural substructures was discussed,and the result shows that the later can be viewed as a special form of the former where the flexural stiffness of the flexural-shear substructures tends to infinity.

  6. Three-dimensional study of dislocation substructures in punch-stretched, AK, DQ, low-carbon steel sheets

    Energy Technology Data Exchange (ETDEWEB)

    Ledezma, M.

    1986-05-01

    Dislocation substructures developed in Aluminum Killed (AK), Drawing Quality (DQ), Low Carbon steel sheets during the Limiting Dome Height (LDH) test are investigated. Thin foils parallel to the sheet plane, longitudinal and transverse sections for different strain ratios have been observed by Transmission Electron Microscopy (TEM). Analysis of the cellular structure in three-dimensions allows the determination of the orientations of the cell wall planes inside individual ferrite grains. The observed cell wall planes for different strain ratios and grain orientations are compared with active slip planes calculated by using the Sach's model for polycrystal deformation. Cell walls are found to be roughly parallel to calculated slip planes for the range of strain ratios considered. Discrepancies observed in negative strain ratio samples are explained in terms of the validity of the Sach's model free-grain assumption.

  7. Definition of a concrete bio-decontamination process in nuclear substructures; Biodegradation de matrices cimentaires en vue de leur decontamination

    Energy Technology Data Exchange (ETDEWEB)

    Jestin, A

    2005-05-15

    The decontamination of sub-structural materials represents a stake of high-importance because of the high volume generated. It is agreed then to propose efficient and effective processes. The process of bio-decontamination of the hydraulic binders leans on the mechanisms of biodegradation of concretes, phenomenon characterized in the 40's by an indirect attack of the material by acids stem from the microbial metabolism: sulphuric acid (produced by Thiobacillus), nitric acid (produced by Nitrosomonas and Nitrobacter) and organic acids (produced by fungi). The principle of the bio-decontamination process is to apply those micro-organisms on the surface of the contaminated material, in order to damage its surface and to retrieve the radionuclides. One of the multiple approaches of the process is the use of a bio-gel that makes possible the micro-organisms application. (author)

  8. Formation and evolution of heavy sub-structures in the centre of galaxy clusters: the local effect of dark energy

    CERN Document Server

    Sedda, Manuel Arca; Merafina, Marco

    2016-01-01

    We discuss how the centres of galaxy clusters evolve in time, showing the results of a series of direct N-body simulations. In particular, we followed the evolution of a galaxy cluster with a mass $M_{clus} \\simeq 10^{14} $M$_{\\odot}$ in different configurations. The dynamical evolution of the system leads in all the cases to the formation of dense and massive sub-structures in the cluster centre, that form in consequence of a series of collisions and merging among galaxies travelling in the cluster core. We investigate how the structural properties of the main merging product depends on the characteristics of those galaxies that contributed to its formation.

  9. 23 CFR 650.409 - Evaluation of bridge inventory.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Evaluation of bridge inventory. 650.409 Section 650.409... Evaluation of bridge inventory. (a) Sufficiency rating of bridges. Upon receipt and evaluation of the bridge inventory, a sufficiency rating will be assigned to each bridge by the Secretary in accordance with...

  10. 23 CFR 650.807 - Bridges requiring a USCG permit.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Bridges requiring a USCG permit. 650.807 Section 650.807... BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.807 Bridges requiring a USCG... improvement or construction of a bridge over navigable waters except for the exemption exercised by FHWA...

  11. 33 CFR 118.65 - Lights on fixed bridges.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on fixed bridges. 118.65 Section 118.65 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.65 Lights on fixed bridges. (a) Each fixed bridge span over a...

  12. 33 CFR 118.70 - Lights on swing bridges.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on swing bridges. 118.70 Section 118.70 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.70 Lights on swing bridges. (a) Swing span lights on through bridges....

  13. 33 CFR 118.85 - Lights on vertical lift bridges.

    Science.gov (United States)

    2010-07-01

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

  14. Finite element of multilayer surfacing systems on orthotropic steel bridges

    NARCIS (Netherlands)

    Li, J.; Liu, X.; Scarpas, A.; Tzimiris, G.

    2013-01-01

    Light weight orthotropic steel bridge decks have been widely utilized for bridges in seismic zones, movable bridges and long span bridges. In the last three decades, severe problems were reported in relation to asphaltic surfacing materials on orthotropic steel deck bridges. Earlier investigations h

  15. Light-weight aluminium bridges and bridge decks. An overview of recent applications

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Kluyver, D. de

    2008-01-01

    The last decades have shown a large increase in the application of aluminium alloys for light-weight bridges. For bridge construction, aluminium alloys have some specific advantages, but also some points of attention. This paper deals with some recent projects of aluminium bridges, and for these pro

  16. The Bridge of Mandolin County

    Science.gov (United States)

    Lantz, Juliette M.; Feindt, Jenny E.; Lewellyn, Eric P. B.; Walczak, Mary M.

    1999-12-01

    The Bridge of Mandolin County is a case designed to teach the general chemistry principles of molar mass, ions and aqueous reactions, solubility rules, and inorganic nomenclature. Through the instructor-facilitated class discussion, students consider the options before the Mandolin Town Council regarding deicing the newly constructed bridge connecting Mandolin with a large nearby city. The students must decipher contradictory claims made on behalf of sodium chloride, the traditional deicer, and calcium magnesium acetate, a new environmentally friendly deicer, to arrive at the most cost-effective and environmentally appropriate deicing product. As they work through the analysis they raise questions that can be addressed in a laboratory setting. Four optional role-playing experiments are included, which can be used by the students to gather information helpful to resolution of the case. The case is intended to be used over two class periods, with a laboratory period in between, though suggestions for other models are provided. Laboratory procedures include an EDTA titration for Ca2+ and Mg2+, a gravimetric analysis, a qualitative examination of ions and solubility, an introduction to freezing point depression and measurement, and an experimental design activity. This case can also successfully be used without alteration in non-majors chemistry or environmental chemistry courses, or upper-level analytical or environmental chemistry courses.

  17. Global monitoring concept for bridges

    Science.gov (United States)

    Bergmeister, Konrad; Santa, Ulrich

    2000-06-01

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

  18. Bridging history and social psychology

    DEFF Research Database (Denmark)

    Glaveanu, Vlad Petre; Yamamoto, Koji

    2012-01-01

    This special issue aims to bridge history and social psychology by bringing together historians and social psychologists in an exercise of reading and learning from each other’s work. This interdisciplinary exercise is not only timely but of great importance for both disciplines. Social psycholog......This special issue aims to bridge history and social psychology by bringing together historians and social psychologists in an exercise of reading and learning from each other’s work. This interdisciplinary exercise is not only timely but of great importance for both disciplines. Social...... psychologists can benefit from engaging with historical sources by being able to contextualise their findings and enrich their theoretical models. It is not only that all social and psychological phenomena have a history but this history is very much part of present-day and future developments. On the other...... hand historians can enhance their analysis of historical sources by drawing upon the conceptual tools developed in social psychology. They can “test” these tools and contribute to their validation and enrichment from completely different perspectives. Most important, as contributions to this special...

  19. Salt-bridge energetics in halophilic proteins.

    Directory of Open Access Journals (Sweden)

    Arnab Nayek

    Full Text Available 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

  20. A Statistical Observation of Crowns and Bridges in 1988 Part 2 : Bridge

    OpenAIRE

    小林, 賢一; 小坂, 茂; 柳田, 史城; 稲生, 衡樹; 大島, 俊明; 高橋, 喜博; 岩井, 啓三; 甘利, 光治; 中根, 卓

    1991-01-01

    A study was made of 207 bridges which had been fabricated for patients at the Prosthodontic Clinic of Matsumoto Dental College during 1988. Some of results were as follows; 1) 47.3% of the patients were males and 52.7% were females. 2) 92.8% of the patients were between 20 and 69 years old. 3) 65.2%of the bridges were fabricated as 3-unit bridges. 4) 77.8% were fabricated as 1-pontic bridges. 5) There were fewer bridge retainers for the lower anterior segment than for other segments. 6) 52.3%...

  1. Heavy Vehicles on Minor Highway Bridges

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Nielsen, Søren R. K.; Enevoldsen, I.

    the results obtained using the numerical models given in details in "Heavy Vehicles on Minor Highway Bridges : dynamic modelling of vehicles and bridges". The models are established using a ordinary vehicle which consists of a 48 t Scania with a 3 axle tractor and a 3 axle trailer, joined in a flexible hinge...

  2. Passing the Einstein-Rosen bridge

    CERN Document Server

    Katanaev, M O

    2013-01-01

    We relax the requirement of geodesic completeness of a space-time. Instead, we require test particles trajectories to be smooth only in the physical sector. Test particles trajectories for Einstein--Rosen bridge are proved to be smooth in the physical sector, and particles can freely penetrate the bridge in both directions.

  3. COUPLING VIBRATION OF VEHICLE-BRIDGE SYSTEM

    Institute of Scientific and Technical Information of China (English)

    陈炎; 黄小清; 马友发

    2004-01-01

    By applying the sinusoidal wave mode to simulate the rugged surface of bridge deck,accounting for vehicle-bridge interaction and using Euler-Bernoulli beam theory, a coupling vibration model of vehicle-bridge system was developed. The model was solved by mode analyzing method and Runge-Kutta method, and the dynamic response and the resonance curve of the bridge were obtained. It is found that there are two resonance regions, one represents the main resonance while the other the minor resonance, in the resonance curve. The influence due to the rugged surface, the vibration mode of bridge, and the interaction between vehicle and bridge on vibration of the system were discussed. Numerical results show that the influence due to these parameters is so significant that the effect of roughness of the bridge deck and the mode shape of the bridge can't be ignored and the vehicle velocity should be kept away from the critical speed of the vehicle.

  4. Active aerodynamic stabilisation of long suspension bridges

    DEFF Research Database (Denmark)

    Nissen, Henrik Ditlev; Sørensen, Paul Haase; Jannerup, Ole Erik

    2004-01-01

    The paper describes the addition of actively controlled appendages (flaps) attached along the length of the bridge deck to dampen wind-induced oscillations in long suppension bridges. A novel approach using control systems methods for the analysis of dynamic stability is presented. In order to ma...

  5. General framework for bridge life cycle design

    Institute of Scientific and Technical Information of China (English)

    Junhai MA; Airong CHEN; Jun HE

    2009-01-01

    Based on a detailed illustration for bridge life cycle design which comprises the processes of service life design, aesthetics design, performance design, environ-mental and ecological design, inspection, maintenance and repair design as well as cost analysis, this paper presented a general framework for bridge life cycle design comprising three design phases and six design processes.

  6. Re-Assessment of Concrete Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper two aspects of re-assessment of the reliability of concrete bridges are discussed namely modelling of the corrosion of reinforcement and updating of uncertain variables. The main reason for deterioration of concrete bridges is corrosion of the reinforcement. Therefore, modelling...

  7. Lifetime Reliability Assessment of Concrete Slab Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    A procedure for lifetime assesment of the reliability of short concrete slab bridges is presented in the paper. Corrosion of the reinforcement is the deterioration mechanism used for estimating the reliability profiles for such bridges. The importance of using sensitivity measures is stressed. Fi...

  8. Precast Pearl-Chain concrete arch bridges

    DEFF Research Database (Denmark)

    Halding, Philip Skov; Hertz, Kristian Dahl; Schmidt, Jacob Wittrup

    2015-01-01

    A Pearl-Chain Bridge is a closed-spandrel arch bridge consisting of a number of straight pre-fabricated so called Super-Light Deck elements put together in an arch shape by post-tensioning cables. Several Pearl-Chain arches can be positioned adjacent to each other by a crane to achieve a bridge...... the technology was used. We also study other important components and details in the Pearl-Chain Bridge concept and review the effects of different types of loads. A theoretical case study of a circular 30 m span Pearl-Chain Bridge is presented showing the influence of a number of parameters: The number of post-tensioning......, and gives a large positive bending moment below the load and a smaller negative bending moment in the unloaded side. When the Pearl-Chain Bridge concept is compared to other pre-fabricated arch bridge solutions we find a number of advantages when using Pearl-Chain Bridges: Straight elements, combination...

  9. The I-35W bridge Project Website

    DEFF Research Database (Denmark)

    Kampf, Constance

    How can websites be used to rebuild trust?  In August 2007, the Interstate Highway 35-W bridge in Minneapolis, MN collapsed during rush hour.  Although many people were rescued and casualties were as limited as could be expected due to quick and effective intervention, the image of a major bridge...... collapsing during rush hour damaged the Minnesota Department of Transportation's reputation and resulted in the loss of public trust for the organization.  The ensuing bridge reconstruction project included a project website intended to rebuild this trust through transparency, community involvement......, and the use of multimodal features.  This paper looks at the I35-W bridge reconstruction project in Minneapolis through web-based communication by the Minnesota Department of Transportation (MnDOT) about the project. The MnDOT bridge reconstruction website will be examined using a combination of 1). Weick...

  10. Seismic response of steel suspension bridge

    Energy Technology Data Exchange (ETDEWEB)

    McCallen, D.B. [Lawrence Livermore National Lab., CA (United States); Astaneh-Asl, A. [California Univ., Berkeley, CA (United States). Dept. of Civil and Environmental Engineering

    1996-11-01

    Performing accurate, realistic numerical simulations of the seismic response of long-span bridges presents a significant challenge to the fields of earthquake engineering and seismology. Suspension bridges in particular represent some of the largest and most important man-made structures and ensuring the seismic integrity of these mega-structures is contingent on accurate estimations of earthquake ground motions and accurate computational simulations of the structure/foundation system response. A cooperative, multi-year research project between the Univ. of California and LLNL was recently initiated to study engineering and seismological issues essential for simulating the response of major structures. Part of this research project is focused on the response of the long-span bridges with the San Francisco-Oakland Bay Bridge serving as a case study. This paper reports on the status of this multi-disciplinary research project with emphasis on the numerical simulation of the transient seismic response of the Bay Bridge.

  11. Optimum Maintenance Strategies for Highway Bridges

    DEFF Research Database (Denmark)

    Frangopol, Dan M.; Thoft-Christensen, Palle; Das, Parag C.;

    As bridges become older and maintenance costs become higher, transportation agencies are facing challenges related to implementation of optimal bridge management programs based on life cycle cost considerations. A reliability-based approach is necessary to find optimal solutions based on minimum...... expected life-cycle costs or maximum life-cycle benefits. This is because many maintenance activities can be associated with significant costs, but their effects on bridge safety can be minor. In this paper, the program of an investigation on optimum maintenance strategies for different bridge types...... is described. The end result of this investigation will be a general reliability-based framework to be used by the UK Highways Agency in order to plan optimal strategies for the maintenance of its bridge network so as to optimize whole-life costs....

  12. Building bridges … and accelerators

    CERN Multimedia

    2009-01-01

    Lyn Evans, the LHC project leader, was awarded an honorary doctorate from the University of Geneva (UNIGE) to celebrate his role not just in building accelerators, but also in building bridges between nations. He was one of four notables honoured at the event on Friday 5 June, coinciding with the University’s 450th Anniversary. Lyn Evans arriving at the ceremony with Archbishop Desmond Tutu. "It was a big surprise when I found out I’d been nominated," recounts Evans, "but it was an even bigger surprise to find out with whom I’d been nominated". At the ceremony Evans was awarded the honorary doctorate along with three others: Archbishop Desmond Tutu, who was acclaimed for his fight against apartheid in South Africa, Mary Robinson, first woman president of Ireland and former United Nations’ high commissioner of human rights, and Pascal Lamy, Director-General of the World Trade Organization. The award ceremony, known as the �...

  13. 基于试验数据的频响函数综合法概述%Review of FRF-based Substructure Method Using Experimental Data

    Institute of Scientific and Technical Information of China (English)

    薛伟敏; 华宏星

    2013-01-01

    利用子结构方法对舰艇上复杂隔振系统进行建模分析时,因子结构的复杂性而无法准确获取其动力学模型,一种解决办法是采用试验测得的子结构频响函数数据进行基于频响函数的子结构综合。为提高子结构频响函数测试结果的精度和基于试验数据的频响函数综合结果的精度,采用频响函数综合算法、子结构频响函数测试误差的消除方法、子结构转角自由度频响函数的测试、频响函数数据的测试及影响因素等几个方面进行总结,并采用基于试验数据的频响函数综合法对一复杂隔振系统进行建模分析,得到较好的效果。可在进行实际隔振系统的子结构测试和综合时提供参考。%When using substructure method to analyze the complex isolator system in ships, it is difficult to establish an accurate dynamic model due to the complexity of the substructure. A possible solution is the frequency response function (FRF)-based substructure synthesizing method by employing experimental FRF’s data. In order to improve the accuracy of the tested FRF data and the synthesized FRF results, the literature reviews on FRF-based substructure synthesizing method by using measured component FRFs were summarized. The topic covers the developed FRF-based algorithms, the numerical techniques to eliminate the measurement errors, the influence and the test of rotational degrees of freedom, common measurement noise and measurement related issues. Finally, the FRF-based substructure method by using experimental FFRs was applied to a real isolation system and good results were obtained. This study has provided a reference for practical application of the FRF-based substructure method.

  14. Oscillations in a sunspot with light bridges

    CERN Document Server

    Yuan, Ding; Huang, Zhenghua; Li, Bo; Su, Jiangtao; Yan, Yihua; Tan, Baolin

    2014-01-01

    Solar Optical Telescope onboard Hinode observed a sunspot (AR 11836) with two light bridges (LBs) on 31 Aug 2013. We analysed a 2-hour \\ion{Ca}{2} H emission intensity data set and detected strong 5-min oscillation power on both LBs and in the inner penumbra. The time-distance plot reveals that 5-min oscillation phase does not vary significantly along the thin bridge, indicating that the oscillations are likely to originate from the underneath. The slit taken along the central axis of the wide light bridge exhibits a standing wave feature. However, at the centre of the wide bridge, the 5-min oscillation power is found to be stronger than at its sides. Moreover, the time-distance plot across the wide bridge exhibits a herringbone pattern that indicates a counter-stream of two running waves originated at the bridge sides. Thus, the 5-min oscillations on the wide bridge also resemble the properties of running penumbral waves. The 5-min oscillations are suppressed in the umbra, while the 3-min oscillations occupy...

  15. Signal and noise in bridging PCR

    Directory of Open Access Journals (Sweden)

    Thaler David S

    2002-07-01

    Full Text Available Abstract Background In a variant of the standard PCR reaction termed bridging, or jumping, PCR the primer-bound sequences are originally on separate template molecules. Bridging can occur if, and only if, the templates contain a region of sequence similarity. A 3' end of synthesis in one round of synthesis that terminates in this region of similarity can prime on the other. In principle, Bridging PCR (BPCR can detect a subpopulation of one template that terminates synthesis in the region of sequence shared by the other template. This study considers the sensitivity and noise of BPCR as a quantitative assay for backbone interruptions. Bridging synthesis is also important to some methods for computing with DNA. Results In this study, BPCR was tested over a 328 base pair segment of the E. coli lac operon and a signal to noise ratio (S/N of approximately 10 was obtained under normal PCR conditions with Taq polymerase. With special precautions in the case of Taq or by using the Stoffel fragment the S/N was improved to 100, i.e. 1 part of cut input DNA yielded the same output as 100 parts of intact input DNA. Conclusions In the E. coli lac operator region studied here, depending on details of protocol, between 3 and 30% per kilobase of final PCR product resulted from bridging. Other systems are expected to differ in the proportion of product that is bridged consequent to PCR protocol and the sequence analyzed. In many cases physical bridging during PCR will have no informational consequence because the bridged templates are of identical sequence, but in a number of special cases bridging creates, or, destroys, information.

  16. Population genetic analysis and sub-structuring of Theileria parva in the northern and eastern parts of Zambia

    Directory of Open Access Journals (Sweden)

    Muleya Walter

    2012-11-01

    Full Text Available Abstract Background Theileriosis, caused by Theileria parva, is an economically important disease in Africa. It is a major constraint to the development of the livestock industry in some parts of eastern, central and southern Africa. In Zambia, theileriosis causes losses of up to 10,000 cattle annually. Methods Cattle blood samples were collected for genetic analysis of Theileria parva from Isoka and Petauke districts in Zambia. Microsatellite analysis was then performed on all Theileria parva positive samples for PCR using a panel of 9 microsatellite markers. Microsatellite data was analyzed using microsatellite toolkit, GenAlEx ver. 6, Fstat ver. 2.9.3.2, and LIAN computer softwares. Results The combined percentage of positive samples in both districts determined by PCR using the p104 gene primers was 54.9% (95% CI: 46.7 – 63.1%, 78/142, while in each district, it was 44.8% (95% CI: 34.8 – 54.8% and 76.1% (95% CI = 63.9 – 88.4% for Isoka and Petauke districts, respectively. We analyzed the population genetic structure of Theileria parva from a total of 61 samples (33 from Isoka and 28 from Petauke using a panel of 9 microsatellite markers encompassing the 4 chromosomes of Theileria parva. Wright’s F index (FST = 0.178 showed significant differentiation between the Isoka and Petauke populations. Linkage disequilibrium was observed when populations from both districts were treated as a single population. When analyzed separately, linkage disequilibrium was observed in Kanyelele and Kalembe areas in Isoka district, Isoka district overall and in Petauke district. Petauke district had a higher multiplicity of infection than Isoka district. Conclusion Population genetic analyses of Theileria parva from Isoka and Petauke districts showed a low level of genotype exchange between the districts, but a high level of genetic diversity within each district population, implying genetic and geographic sub-structuring between the districts. The sub-structuring

  17. Building the clinical bridge: an Australian success.

    Science.gov (United States)

    Wallis, Marianne; Chaboyer, Wendy

    2012-01-01

    Nursing effectiveness science includes primary, secondary, and translational, clinically focused research activities which aim to improve patient or client outcomes. It is imperative, for the successful conduct of a program of nursing effectiveness science, that a clinical bridge is established between academic and healthcare service facilities. An Australian example of the development of a robust clinical bridge through the use of jointly funded positions at the professorial level is outlined. In addition, an analysis of the practical application of Lewin's model of change management and the contribution of both servant and transformational leadership styles to the bridge building process is provided.

  18. Building the Clinical Bridge: An Australian Success

    Directory of Open Access Journals (Sweden)

    Marianne Wallis

    2012-01-01

    Full Text Available Nursing effectiveness science includes primary, secondary, and translational, clinically focused research activities which aim to improve patient or client outcomes. It is imperative, for the successful conduct of a program of nursing effectiveness science, that a clinical bridge is established between academic and healthcare service facilities. An Australian example of the development of a robust clinical bridge through the use of jointly funded positions at the professorial level is outlined. In addition, an analysis of the practical application of Lewin’s model of change management and the contribution of both servant and transformational leadership styles to the bridge building process is provided.

  19. Asymptotics of a horizontal liquid bridge

    Science.gov (United States)

    Haynes, M.; O'Brien, S. B. G.; Benilov, E. S.

    2016-04-01

    This paper uses asymptotic techniques to find the shape of a two dimensional liquid bridge suspended between two vertical walls. We model the equilibrium bridge shape using the Laplace-Young equation. We use the Bond number as a small parameter to deduce an asymptotic solution which is then compared with numerical solutions. The perturbation approach demonstrates that equilibrium is only possible if the contact angle lies within a hysteresis interval and the analysis relates the width of this interval to the Bond number. This result is verified by comparison with a global force balance. In addition, we examine the quasi-static evolution of such a two dimensional bridge.

  20. Calculations in bridge aeroelasticity via CFD

    Energy Technology Data Exchange (ETDEWEB)

    Brar, P.S.; Raul, R.; Scanlan, R.H. [Johns Hopkins Univ., Baltimore, MD (United States)

    1996-12-31

    The central focus of the present study is the numerical calculation of flutter derivatives. These aeroelastic coefficients play an important role in determining the stability or instability of long, flexible structures under ambient wind loading. A class of Civil Engineering structures most susceptible to such an instability are long-span bridges of the cable-stayed or suspended-span variety. The disastrous collapse of the Tacoma Narrows suspension bridge in the recent past, due to a flutter instability, has been a big impetus in motivating studies in flutter of bridge decks.

  1. Gust loading on streamlined bridge decks

    DEFF Research Database (Denmark)

    Larose, Guy; Mann, Jakob

    1998-01-01

    The current analytical description of the buffeting action of wind on long-span bridges is based on the strip assumption. However, recent experiments on closed-box girder bridge decks have shown that this assumption is not valid and is the source of an important part of the error margin...... of the analytical prediction methods. In this paper, an analytical model that departs from the strip assumption is used to describe the gust loading on a thin airfoil. A parallel is drawn between the analytical model and direct measurements of gust loading on motionless closed-box girder bridge decks. Empirical...

  2. Transformation of the bridge during drop separation

    Science.gov (United States)

    Chashechkin, Yu. D.; Prokhorov, V. E.

    2016-05-01

    The geometry of flows during separation of pendant drops of liquids with significantly different physical properties (alcohol, water, glycerin, oil) has been studied by high-speed video recording. The dynamics of the processes involving the formation of bridges of two characteristic shapes—slightly nonuniform in thickness and with thinning of the upper and lower ends—has been investigated. It has been shown that the shape change of the separated bridge has a number of stages determined by the properties of the liquid. As a result, the bridge is transformed into a small drop—a satellite drop.

  3. Closure technique for the hybrid girder cable stayed bridge of Edong Bridge

    Institute of Scientific and Technical Information of China (English)

    Liu Minghu; Tan Hao; Xu GuoPing; Zhao Canhui

    2012-01-01

    Based on Edong Yangtze River Bridge, which is the second longest hybrid girder cable stayed bridge with 926 m long main span, the influencing factors and crucial techniques of the main span closure method for long span hybrid girder cable stayed bridge are studied. After theoretical analysis, numerical evaluation and practical test, the loading assistant closure method is employed in Edong Yangtze River Bridge. The loading assistant closure method, with better thermal adaptability and less influence on bridge line and the forced status, can meet the requirements of the unstressed state control method. Based on the mentioned advantages, the loading assistant closure method is applicable to long span hybrid girder cable stayed bridges. The conclusion can provide a reference for the further design of the similar brid~es.

  4. Superposed epoch study of ICME sub-structures near Earth and their effects on galactic cosmic rays

    CERN Document Server

    Masías-Meza, J J; Démoulin, P; Rodriguez, L; Janvier, M

    2016-01-01

    Interplanetary coronal mass ejections (ICMEs) are the interplanetary manifestations of solar eruptions. The overtaken solar wind forms a sheath of compressed plasma at the front of ICMEs. Magnetic clouds (MCs) are a subset of ICMEs with specific properties (e.g. the presence of a flux rope). When ICMEs pass near Earth, ground observations indicate that the flux of galactic cosmic rays (GCRs) decreases. The main aims of this paper are to find: common plasma and magnetic properties of different ICME sub-structures, and which ICME properties affect the flux of GCRs near Earth. We use a superposed epoch method applied to a large set of ICMEs observed \\insitu\\ by the spacecraft ACE, between 1998 and 2006. We also apply a superposed epoch analysis on GCRs time series observed with the McMurdo neutron monitors. We find that slow MCs at 1 AU have on average more massive sheaths. We conclude that it is because they are more effectively slowed down by drag during their travel from the Sun. Slow MCs also have a more sym...

  5. The Centrality Dependence of the Parton Bubble Model for high energy heavy ion collisions and fireball surface substructure at RHIC

    CERN Document Server

    Lindenbaum, S J

    2008-01-01

    In an earlier paper we developed a QCD inspired theoretical parton bubble model (PBM) for RHIC/LHC. The PBM quantitatively agreed with the strong charged particle pair correlations observed by the STAR collaboration at RHIC in the highest energy Au + Au central collisions, and also agreed with the Hanbury Brown and Twiss (HBT) observed small final state source size approximately 2f radii in the transverse momentum range above 0.8 GeV/c. The model assumed a substructure of a ring of localized adjoining 2f radius bubbles(gluonic hot spots) perpendicular to the collider beam direction, centered on the beam, at mid-rapidity and located on the expanding fireball surface of the Au + Au collisions. In this paper we extend the model (PBME) to include the changing development of bubbles with centrality from the most central region where bubbles are very important to the most peripheral where the bubbles are gone. Energy density is found to be related to bubble formation and as centrality decreases the maximum energy d...

  6. QSAR model toward the rational design of new agrochemical fungicides with a defined resistance risk using substructural descriptors.

    Science.gov (United States)

    Speck-Planche, Alejandro; Kleandrova, Valeria V; Rojas-Vargas, Julio A

    2011-11-01

    The increasing resistance of several phytopathogenic fungal species to the existing agrochemical fungicides has alarmed to the worldwide scientific community. There is no available methodology to predict in an efficient way if a new fungicide will have resistance risk due to fungal species which cause considerable crop losses. In an attempt to overcome this problem, a multi-resistance risk QSAR model, based on substructural descriptors was developed from a heterogeneous database of compounds. The purpose of this model is the classification, design, and prediction of agrochemical fungicides according to resistance risk categories. The QSAR model classified correctly 85.11% of the fungicides and the 85.07% of the inactive compounds in the training series, for an accuracy of 85.08%. In the prediction series, the percentages of correct classification were 85.71 and 86.55% for fungicides and inactive compounds, respectively, with an accuracy of 86.39%. Some fragments were extracted and their quantitative contributions to the fungicidal activity were calculated taking into consideration the different resistance risk categories for agrochemical fungicides. In the same way, some fragments present in molecules with fungicidal activity and with negative contributions were analyzed like structural alerts responsible of resistance risk.

  7. Combined histamine H1/H2 receptor antagonists: part I. Pharmacological hybrids with pheniramine- and roxatidine-like substructures.

    Science.gov (United States)

    Schulze, F R; Buschauer, A; Schunack, W

    1998-07-01

    A series of hybrid compounds combining the pharmacophores of both pheniramine-type histamine H1 receptor antagonists and roxatidine-type H2 receptor antagonists have been synthesized and tested for histamine antagonism at the isolated ileum (H1) and the spontaneously beating right atrium (H2) of the guinea pig. The 'polar group' of the H2 antagonist moiety (cyanoguanidine, nitroethenediamine or urea) and the side chain amino group of the H1 antagonist portion have been linked by a polymethylene spacer or by a piperazine system. The incorporation of a flexible spacer (2-7 methylene groups) resulted in H1 antagonists achieving up to 2.4 times the activity of pheniramine. Depending on the nature of the polar group the highest H2 antagonist potency resides in compounds with spacers ?2 methylene groups. Nitroethenediamine 24c with a seven-membered chain and a chlorpheniramine substructure proved to be approximately equipotent with pheniramine at the H1 and with ranitidine at the H2 receptor (pKB values 7.82 and 7.1, respectively).

  8. The Effects of Low-Energy Nitrogen Ion Implantation on Pollen Exine Substructure and Pollen Germination of Cedrus deodara

    Institute of Scientific and Technical Information of China (English)

    Li Guoping; Huang Qunce; Qin Guangyong; Huo Yuping

    2005-01-01

    The aim of this study is to investigate the biological effects of ion beams on pollen.Pollen grains of Cedrus deodara were implanted with 30 keV nitrogen ion beams at doses ranging from 1 × 1015 ions/cm2 to 15 × 1015 ions/cm2. The effects of N+ implantation on the pollen exine substructure were examined using an atomic force microscope (AFM), and the structure and morphology of pollen and pollen tubes were observed using a laser scanning confocal microscope (LSCM). AFM observations distinctly revealed the erosion of the pollen exine caused by N+implantation in the micrometer to nanometer range. Typical results showed that the erosion degree was linearly proportional to the ion dose. Pollen germination experiments in vitro indicated that N+ implantation within a certain dose range increased the rate of pollen germination. The main abnormal phenomena in pollen tubes were also analyzed. Our results suggest that low energy ion implantation with suitable energy and dosage can be used to break the pollen wall to induce a transfer of exogenous DNA into the pollen without any damage to the cytoplasm and nuclei of the pollen. The present study suggests that a combination of the method of ion-beam-induced gene transfer and the pollen-tube pathway method (PTPW) would be a new plant transformation method.

  9. Diode-quad bridge circuit means

    Science.gov (United States)

    Harrison, D. R.; Dimeff, J. (Inventor)

    1975-01-01

    A transducer and frequency discriminator circuit is described including a four-terminal circulating diode bridge, a first pair of capacitors connected in series across two terminals of the bridge, and a second pair of capacitors, or other impedance elements, connected in series across the other two terminals of the bridge. A source of balanced alternating electrical energy for energizing the circuit is coupled between the commonly connected plates of the first pair of capacitors and the commonly connected plates of the second pair of capacitors. Due to the operation of the diode bridge, the sum of the resultant charges developed on the first pair of capacitors is proportional to the relationship between the respective capacitors of the second pair, and consequently, an output voltage taken across the first pair of capacitors will be proportional to that relationship.

  10. Allegheny County-Owned Bridges Points

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset shows the location of bridges owned by Allegheny County as centroids. If viewing this description on the Western Pennsylvania Regional Data Center’s...

  11. Allegheny County-Owned Bridges Centerlines

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset shows the bridges owned by Allegheny County. If viewing this description on the Western Pennsylvania Regional Data Center’s open data portal...

  12. Relaxation of liquid bridge after droplets coalescence

    Directory of Open Access Journals (Sweden)

    Jiangen Zheng

    2016-11-01

    Full Text Available We investigate the relaxation of liquid bridge after the coalescence of two sessile droplets resting on an organic glass substrate both experimentally and theoretically. The liquid bridge is found to relax to its equilibrium shape via two distinct approaches: damped oscillation relaxation and underdamped relaxation. When the viscosity is low, damped oscillation shows up, in this approach, the liquid bridge undergoes a damped oscillation process until it reaches its stable shape. However, if the viscous effects become significant, underdamped relaxation occurs. In this case, the liquid bridge relaxes to its equilibrium state in a non-periodic decay mode. In depth analysis indicates that the damping rate and oscillation period of damped oscillation are related to an inertial-capillary time scale τc. These experimental results are also testified by our numerical simulations with COMSOL Multiphysics.

  13. Wheatstone bridge technique for magnetostriction measurements.

    Science.gov (United States)

    Sullivan, M

    1980-03-01

    A basic Wheatstone bridge, with additional electronic instrumentation, has been used in the measurement of magnetostriction. This method allows a resolution of approximately 10% on measurements of magnetostrictions less than 0.75 parts per million.

  14. VT Short Structures - Bridges and Culverts

    Data.gov (United States)

    Vermont Center for Geographic Information — Inspection data for structures (bridge and culvert) between 6 feet and 20 feet in length inspected on State road system. Stewards: Information Technology, Data...

  15. VT Long Structures - Bridges and Culverts

    Data.gov (United States)

    Vermont Center for Geographic Information — Inspection data for structures (bridge and culvert) greater than 20 feet in length inspected on both State and local road systems. Stewards: Information Technology,...

  16. Active Control of Long Bridges Using Flaps

    DEFF Research Database (Denmark)

    Hansen, H. I.; Thoft-Christensen, Palle

    The main problem in designing ultra-long span suspension bridges is flutter. A solution to this problem might be to introduce an active flap control system to increase the flutter wind velocity. The investigated flap control system consists of flaps integrated in the bridge girder so each flap...... is the streamlined part of the edge of the girder. Additional aerodynamic derivatives are shown for the flaps and it is shown how methods already developed can be used to estimate the flutter wind velocity for a bridge section with flaps. As an example, the flutter wind velocity is calculated for different flap...... configurations for a bridge section model by using aerodynamic derivatives for a flat plate. The example shows that different flap configurations can either increase or decrease the flutter wind velocity. for optimal flap configurations flutter will not occur....

  17. Pilot testing of a hydraulic bridge exciter

    Directory of Open Access Journals (Sweden)

    Andersson Andreas

    2015-01-01

    Full Text Available This paper describes the development of a hydraulic bridge exciter and its first pilot testing on a full scale railway bridge in service. The exciter is based on a hydraulic load cylinder with a capacity of 50 kN and is intended for controlled dynamic loading up to at least 50 Hz. The load is applied from underneath the bridge, enabling testing while the railway line is in service. The system is shown to produce constant load amplitude even at resonance. The exciter is used to experimentally determine frequency response functions at all sensor locations, which serve as valuable input for model updating and verification. An FE-model of the case study bridge has been developed that is in good agreement with the experimental results.

  18. Practical Approach to Fragility Analysis of Bridges

    Directory of Open Access Journals (Sweden)

    Yasamin Rafie Nazari

    2012-12-01

    Full Text Available Damages during past earthquakes reveal seismic vulnerability of bridge structures and the necessity of probabilistic approach toward seismic performance evaluation of bridges and its interpretation in terms of decision variables such as repair cost, downtime and life loss. This Procedure involves hazard analysis, structural analysis, damage analysis and loss analysis. The purpose of present study is reviewing different methods developed to derive fragility curves for damage analysis of bridges and demonstrating a simple procedure for fragility analysis using Microsoft Office Excel worksheet to reach probability of occurring predefined level of damage due to different levels of seismic demand parameters. The input of this procedure is the intensity of ground motion and the output is an appropriate estimate of the expected damage. Different observed damages of the bridges are discussed and compared the practical definition of damage states. Different methods of fragility analyses are discussed and a practical step by step example is illustrated.

  19. Identifying hidden sexual bridging communities in Chicago.

    Science.gov (United States)

    Youm, Yoosik; Mackesy-Amiti, Mary Ellen; Williams, Chyvette T; Ouellet, Lawrence J

    2009-07-01

    Bridge populations can play a central role in the spread of human immunodeficiency virus (HIV) by providing transmission links between higher and lower prevalence populations. While social network methods are well suited to the study of bridge populations, analyses tend to focus on dyads (i.e., risk between drug and/or sex partners) and ignore bridges between distinct subpopulations. This study takes initial steps toward moving the analysis of sexual network linkages beyond individual and risk group levels to a community level in which Chicago's 77 community areas are examined as subpopulations for the purpose of identifying potential bridging communities. Of particular interest are "hidden" bridging communities; that is, areas with above-average levels of sexual ties with other areas but whose below-average AIDS prevalence may hide their potential importance for HIV prevention. Data for this analysis came from the first wave of recruiting at the Chicago Sexual Acquisition and Transmission of HIV Cooperative Agreement Program site. Between August 2005 through October 2006, respondent-driven sampling was used to recruit users of heroin, cocaine, or methamphetamine, men who have sex with men regardless of drug use, the sex partners of these two groups, and sex partners of the sex partners. In this cross-sectional study of the sexual transmission of HIV, participants completed a network-focused computer-assisted self-administered interview, which included questions about the geographic locations of sexual contacts with up to six recent partners. Bridging scores for each area were determined using a matrix representing Chicago's 77 community areas and were assessed using two measures: non-redundant ties and flow betweenness. Bridging measures and acquired immunodeficiency syndrome (AIDS) case prevalence rates were plotted for each community area on charts representing four conditions: below-average bridging and AIDS prevalence, below-average bridging and above

  20. 49 CFR 237.33 - Content of bridge management programs.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Content of bridge management programs. 237.33... Content of bridge management programs. Each bridge management program adopted in compliance with this part... spans, span lengths, and all other information necessary to provide for the management of bridge...

  1. 23 CFR 650.705 - Application for discretionary bridge funds.

    Science.gov (United States)

    2010-04-01

    ... TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Discretionary Bridge Candidate Rating Factor § 650... cost, current average daily truck traffic and a narrative describing the existing bridge, the proposed new or rehabilitated bridge and other relevant factors which the State believes may warrant...

  2. 33 CFR 118.80 - Lights on bascule bridges.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on bascule bridges. 118.80 Section 118.80 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.80 Lights on bascule bridges. (a) Lift span lights. Each lift span...

  3. 33 CFR 118.90 - Bridges crossing channel obliquely.

    Science.gov (United States)

    2010-07-01

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

  4. 23 CFR 650.809 - Movable span bridges.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Movable span bridges. 650.809 Section 650.809 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.809 Movable span bridges. A fixed...

  5. Detection of salt bridges to lysines in solution in barnase

    DEFF Research Database (Denmark)

    Hansen, Poul Erik; Williamson, Michael P.; Hounslow, Andrea M.

    2013-01-01

    We show that salt bridges involving lysines can be detected by deuterium isotope effects on NMR chemical shifts of the sidechain amine. Lys27 in the ribonuclease barnase is salt bridged, and mutation of Arg69 to Lys retains a partially buried salt bridge. The salt bridges are functionally important....

  6. Inspection Based Evaluation of a Danish Road Bridge

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper it is shown how an inspection-based evaluation of a Danish road bridge may be performed using the BRIDGE1 and BRIDGE2 bridge management systems produced within the EC-supported research programme "Assessment of Performance and Optimal Strategies for Inspection and Maintenance...

  7. Micromechanical model of cross-over fibre bridging - Prediction of mixed mode bridging laws

    DEFF Research Database (Denmark)

    Sørensen, Bent F.; Gamstedt, E.K.; Østergaard, Rasmus Christian;

    2008-01-01

    on the observed bridging mechanism, a micromechanical model is developed for the prediction of macroscopic mixed mode bridging laws (stress-opening laws). The model predicts a high normal stress for very small openings, decreasing rapidly with increasing normal and tangential crack opening displacements......The fracture resistance of fibre composites can be greatly enhanced by crack bridging. In situ observations of mixed mode crack growth in a unidirectional carbon-fibre/epoxy composite reveal crack bridging by single fibres and by beam-like ligaments consisting of several fibres. Based...

  8. The effect of a disc on the population of cuspy and cored dark matter substructures in Milky Way-like galaxies

    CERN Document Server

    Errani, Raphaël; Laporte, Chervin F P; Gómez, Facundo A

    2016-01-01

    We use high-resolution $N$-body simulations to study the effect of a galactic disc on the dynamical evolution of dark matter substructures with orbits and structural parameters extracted from the Aquarius A-2 merger tree (Springel et al. 2008). Satellites are modelled as equilibrium $N$-body realizations of generalized Hernquist profiles with $2\\times10^6$ particles and injected in the analytical evolving host potential at $z_\\mathrm{infall}$, defined by the peak of their mass evolution. We select all substructures with $M_{200}(z_\\mathrm{infall})\\geq 10^8\\,\\mathrm{M_\\odot}$ and first pericentric distances $r_psubstructures at $z=0$ than their cored counterparts, and four times as many if we only consider those on orb...

  9. Thermal Bridge Effects in Walls Separating Rowhouses

    DEFF Research Database (Denmark)

    Rose, Jørgen

    1997-01-01

    In this report the thermal bridge effects at internal wall/roof junctions in rowhouses are evaluated. The analysis is performed using a numerical calculation programme, and different solutions are evaluated with respect to extra heat loss and internal surface temperatures.......In this report the thermal bridge effects at internal wall/roof junctions in rowhouses are evaluated. The analysis is performed using a numerical calculation programme, and different solutions are evaluated with respect to extra heat loss and internal surface temperatures....

  10. Heavy Vehicles on Minor Highway Bridges

    DEFF Research Database (Denmark)

    Nielsen, Søren R. K.; Kirkegaard, Poul Henning; Enevoldsen, I.

    The present paper worked out as a part of a research project on "Dynamic amplification factor of vehicle loadings on smaller bridges" establishes a two-dimensional spectral description of the road roughness surface based on measurements from a Danish road using so-called Profilograph used by Danish...... to the bridge and the stochastic nature of the surface roughness are included into the model....

  11. Earthquake Resistance of Integral Abutment Bridges

    OpenAIRE

    2009-01-01

    intermediate length bridges. Integral abutment construction eliminates joints and bearings which reduce long-term maintenance costs. However, in the absence of joints and bearings, the bridge abutments and foundations must be able to accommodate lateral movements from thermal expansion and contraction of the superstructure and from seismic events. Previous research has focused on the response to thermal expansion and contraction. The current research examines the response of integral abutment...

  12. Arch bridges – unlocking their potential

    OpenAIRE

    Long, Adrian; Nanukuttan, Sreejith

    2016-01-01

    Arch bridges are strong, durable, aesthetically pleasing and require little maintenance but very few have been built since the early 1900s. However, this trend has changed as more than 60 FlexiArch bridges have been installed since the system was launched in 2007. The FlexiArch uses precast concrete voussoirs, requires neither corrodible reinforcement, nor centring, can be installed in hours and is contractor friendly. Details of this innovative method of construction and installation of arch...

  13. External Prestressing Bridge Reinforcement Technology Review

    Directory of Open Access Journals (Sweden)

    Zhu Hanbing

    2015-01-01

    Full Text Available Externally prestressed bridge can not only limit and reduce the cracks and deformation of the structure, improve the rigidity and bearing capacity of structure, improve the stress state of structure, but also have less interference for bridge operation when it is operating and have the good economic efficiency. This paper introduces the advantages and disadvantages of external prestressed strengthening technique, its calculation theory and construction technology described in detail, and finally the paper discusses the deficiency of existing research.

  14. Framework for Bridges Maintenance in Egypt

    Directory of Open Access Journals (Sweden)

    Hesham Abd Elkhalek

    2016-01-01

    Full Text Available The traditional approaches for bridges maintenance is proven to be inefficient as they lead to random way of spending maintenance budget and deteriorating bridge conditions. In many cases, maintenance activities are performed due to user complaints. The objective of this paper is to develop a practical and reliable framework to manage the maintenance and repair activities of Bridges network in Egypt considering performance and budget limits. The model solves an optimization problem that maximizes the average condition of the network given the limited budget using Genetic Algorithm (GA. The main tasks of the system are bridge inventory, condition assessment, deterioration using markov model, and maintenance optimization. The developed model takes into account multiple parameters including serviceability requirements, budget allocation, element importance on structural safety and serviceability, bridge impact on network, and traffic. A questionnaire is conducted to complete the research scope. The proposed model is implemented in software, which provides a friendly user interface. The results of the framework are multi – year maintenance plan for the entire network for up to five years. A case study is presented for validating and testing the model with Data collected from “General Authority for Roads, Bridges and Land Transport” in Egypt.

  15. I-5/Gilman advanced technology bridge project

    Science.gov (United States)

    Lanza di Scalea, Francesco; Karbhari, Vistasp M.; Seible, Frieder

    2000-04-01

    The UCSD led I-5/Gilman Advanced Technology Bridge Project will design and construct a fully functional traffic bridge of advanced composite materials across Interstate 5 in La Jolla, California. Its objective is to demonstrate the use of advanced composite technologies developed by the aerospace industry in commercial applications to increase the life expectancy of new structures and for the rehabilitation of aging infrastructure components. The structure will be a 450 ft long, 60 ft wide cable-stayed bridge supported by a 150 ft A-frame pylon with two vehicular lanes, two bicycle lanes, pedestrian walkways and utility tunnels. The longitudinal girders and pylon will be carbon fiber shells filled with concrete. The transverse deck system will consist of hollow glass/carbon hybrid tubes and a polypropylene fiber reinforced concrete deck with an arch action. Selected cables will be composite. The bridge's structural behavior will be monitored to determine how advanced composite materials perform in civil infrastructure applications. The bridge will be instrumented to obtain performance and structural health data in real time and, where possible, in a remote fashion. The sensors applied to the bridge will include electrical resistance strain gages, fiberoptic Bragg gratings and accelerometers.

  16. Numerical simulation on continuous collapse of reinforced concrete girder bridge subjected to vessel collision%钢筋混凝土梁桥船舶撞击连续倒塌数值模拟

    Institute of Scientific and Technical Information of China (English)

    姜华; 王君杰; 贺拴海

    2012-01-01

    The material model and failure index of the element in numerical simulation of the collapse of reinforced concrete bridge under vessel collision were introduced, and then the delicate finite element models for bridge superstructure, substructure and support saddle were set up, where the elastoplastic damage cap model was used for concrete and the elastoplaslic kinematic hardening model was used for steel bar. The numerical simulation of the collapse process of bridge structure caused by vessel collision was carried out and the collapse mechanism of continuous girder bridge was revealed.%详细介绍了钢筋混凝土桥梁船撞倒塌模拟涉及的材料模型和单元失效指标等问题,建立某连续梁上部、下部结构、支座和船舶结构精细有限元模型,将弹塑性损伤帽盖模型用于混凝土,弹塑性随动强化模型用于钢筋,对船舶撞击钢筋混凝土连续梁引起的结构连续倒塌过程进行了数值模拟,揭示了连续梁桥结构的船撞倒塌机理.

  17. Simplified Model Research on Framed Spherical Tank Seismic Substructure%支架式球形储罐子结构简化模型

    Institute of Scientific and Technical Information of China (English)

    周利剑; 孙铭阳; 王雪

    2016-01-01

    近些年,地震的发生频率呈现上升趋势,而抗震研究的重要性也日益提高。作为新兴的抗震试验方法——子结构振动台试验方法,也日趋被人们所重视。采用4种方法对支架式球形储罐进行模态分析,得到合理的简化全模型。在全模型基础上进行子结构简化模型划分求解,对比分析出从结构下两层处划分结构为最合理的子结构简化模型形式。在支架式储罐子结构研究中,把下两层支架部分作为试验子结构,将整体划分成双质点体系进行后续抗震性能试验研究。%In recent years, the frequency that the earthquakes occur shows a tendency of raising, and the importance of the seismic method is increasing gradually. As a new seismic experiment method, substructure shaking table experiment method becomes attention by people increasingly. This paper takes four methods to carry out the modal analysis of the framed spherical storage tank and get a reasonable simplified model. By deciding and solving the simplified model of the substructure on the basis of the whole model,it came to the con-clusion that most reasonable simplified model form of substructure is that dividing the structure from the two layers of the structure. In the research of the substructure about the framed spherical tank, treat the two layers of the structure as test substructure, and the whole struc-ture regard as two particle system experiments were carried out to study the seismic perfor-mance of the following.

  18. A Tale of Five Bridges; the use of GNSS for Monitoring the Deflections of Bridges

    Science.gov (United States)

    Roberts, Gethin Wyn; Brown, Christopher J.; Tang, Xu; Meng, Xiaolin; Ogundipe, Oluropo

    2014-11-01

    The first Bridge Monitoring surveying was carried out in 1996 by the authors, through attaching Ashtech ZXII GPS receivers onto the Humber Bridge' parapet, and gathering and further analysing the resulting 1 Hz RTK GPS data. Various surveys have subsequently been conducted on the Humber Bridge, the Millennium Bridge, the Forth Road Bridge, the Severn Suspension Bridge and the Avonmouth Viaduct. These were all carried out using survey grade carrier phase/pseudorange GPS and later GNSS receivers. These receivers were primarily dual frequency receivers, but the work has also investigated the use of single frequency receivers, gathering data at 1 Hz, 10 Hz, 20 Hz and even 100 Hz. Various aspects of the research conducted are reported here, as well as the historical approach. Conclusions are shown in the paper, as well as lessons learnt during the development of this work. The results are compared to various models that exist of the bridges' movements, and compare well. The results also illustrate that calculating the frequencies of the movements, as well as looking at the magnitudes of the movements, is an important aspect of this work. It is also shown that in instances where the magnitudes of the movements of the bridge under investigation are small, it is still possible to derive very accurate frequencies of the movements, in comparison to the existing models.

  19. Role of multiprotein bridging factor 1 in archaea: bridging the domains?

    NARCIS (Netherlands)

    Koning, de B.; Blombach, F.; Wu Hao,; Brouns, S.J.J.; Oost, van der J.

    2009-01-01

    MBF1 (multiprotein bridging factor 1) is a highly conserved protein in archaea and eukaryotes. It was originally identified as a mediator of the eukaryotic transcription regulator BmFTZ-F1 (Bombyx mori regulator of fushi tarazu). MBF1 was demonstrated to enhance transcription by forming a bridge bet

  20. Study of Landscape Design of Arch Bridges in Garden%园林中拱桥的景观设计研究

    Institute of Scientific and Technical Information of China (English)

    贾艳敏; 唐军斌; 于广龙

    2013-01-01

    To provided reference for the landscape design of arch bridges in garden, the principles (including the coordinated proportions, proper dimensions, balanced layout, graceful rhythm, rich implications and environmental merging) and procedures of the landscape design of the bridges were summarized and the practicability of the arch bridge types (including the solid spandrel arch bridge, open spandrel arch bridge, rigid-frame arch bridge, composite system arch bridge and irregularly shaped arch bridge) commonly employed for the brides in garden was analyzed. On the basis of the summarization and analysis, a landscape arch bridge for the Xiangfang Park, Harbin was designed. The bridge is a three-span continuous composite arch structure with span arrangement (15 + 30 + 15) m and rise-to-span ratio 1/5. In the transverse direction of the superstructure of the bridge, two arch ribs are employed. The transverse length of an arch rib is 3. 0 m, the spacing distance between the arch ribs is 3. 5 m and in between the arch ribs, the lateral bracings are not provided. The substructure of the bridge is of the bored piles and pile caps. The balustrades are designed into the ones having each vertical plate plus a railing and are configurated into the shape of swan. The bridge after the landscape design has clear force lines, simple and smooth structure and hence becomes a graceful and harmonious scene together with its surrounding environment.%为对园林中拱桥的景观设计提供参考,总结园林中拱桥景观的设计原则(比例协调、尺度恰当;均衡匀称、韵律优美;富于内涵、融于环境)与步骤,并对园林拱桥常见桥型(实腹拱桥、空腹拱桥、刚架拱桥、组合体系拱桥、异型拱桥)的实用性进行分析,以此为基础对哈尔滨香坊公园中的一座景观拱桥进行设计.该桥采用(15+30+15)m三跨连续拱式组合结构,矢跨比为1/5.上部结构横向采用2片拱肋,拱肋横向长度为3.0m,间距3.5m,拱肋

  1. Superposed epoch study of ICME sub-structures near Earth and their effects on Galactic cosmic rays

    Science.gov (United States)

    Masías-Meza, J. J.; Dasso, S.; Démoulin, P.; Rodriguez, L.; Janvier, M.

    2016-08-01

    Context. Interplanetary coronal mass ejections (ICMEs) are the interplanetary manifestations of solar eruptions. The overtaken solar wind forms a sheath of compressed plasma at the front of ICMEs. Magnetic clouds (MCs) are a subset of ICMEs with specific properties (e.g. the presence of a flux rope). When ICMEs pass near Earth, ground observations indicate that the flux of Galactic cosmic rays (GCRs) decreases. Aims: The main aims of this paper are to find common plasma and magnetic properties of different ICME sub-structures and which ICME properties affect the flux of GCRs near Earth. Methods: We used a superposed epoch method applied to a large set of ICMEs observed in situ by the spacecraft ACE, between 1998 and 2006. We also applied a superposed epoch analysis on GCRs time series observed with the McMurdo neutron monitors. Results: We find that slow MCs at 1 AU have on average more massive sheaths. We conclude that this is because they are more effectively slowed down by drag during their travel from the Sun. Slow MCs also have a more symmetric magnetic field and sheaths expanding similarly as their following MC, while in contrast, fast MCs have an asymmetric magnetic profile and a sheath in compression. In all types of MCs, we find that the proton density and the temperature and the magnetic fluctuations can diffuse within the front of the MC due to 3D reconnection. Finally, we derive a quantitative model that describes the decrease in cosmic rays as a function of the amount of magnetic fluctuations and field strength. Conclusions: The obtained typical profiles of sheath, MC and GCR properties corresponding to slow, middle, and fast ICMEs, can be used for forecasting or modelling these events, and to better understand the transport of energetic particles in ICMEs. They are also useful for improving future operative space weather activities.

  2. The effects of ellipticity and substructure on estimates of cluster density profiles based on lensing and kinematics

    Science.gov (United States)

    Meneghetti, Massimo; Bartelmann, Matthias; Jenkins, Adrian; Frenk, Carlos

    2007-10-01

    We address the question of how well the density profile of galaxy clusters can be determined by combining strong lensing and velocity dispersion data. We use cosmological dark matter simulations of clusters to test the reliability of the method, producing mock catalogues of tangential and radial gravitational arcs and simulating the radial velocity dispersion profile of the cluster brightest central galaxy. The density profiles of the simulated clusters closely follow the Navarro, Frenk & White (NFW) form, but we find that the recovered values of the inner slope are systematically underestimated, by about 0.4 in the mean, if the lens is assumed to be axially symmetric. However, if the ellipticity and orientation of the isocontours of the cluster lensing potential are taken into account, then the inner slopes can be recovered quite accurately for a significant subset of the clusters whose central surface density profiles appear the most regular. These have lensing potentials with ellipticities in the range 0.15-0.4. Further simulations projecting one cluster along many random lines of sight show that, even for lower ellipticities, the central slopes are underestimated by ~10-35per cent. These simulations closely mimic past observations, suggesting that existing estimates of the central slopes may be biased towards low values. For the remaining clusters, where the lensing potential is strongly perturbed by active merging or by substructure, the correct determination of the inner slope requires a more accurate model for the lens. When the halo profile is modelled by a generalized NFW profile, we find that the inferred scale radius and characteristic density, unlike the inner slope, are generally poorly constrained, since there is a strong degeneracy between these two parameters.

  3. Application of Improved Hybrid Interface Substructural Component Modal Synthesis Method inVibration Characteristics of Mistuned Blisk

    Institute of Scientific and Technical Information of China (English)

    BAI Bin,BAI Guangchen,; LI Chao

    2014-01-01

    The large and complex structures are divided into hundreds of thousands or millions degrees of freedom(DOF) when they are calculated which will spend a lot of time and the efficiency will be extremely low. The classical component modal synthesis method (CMSM) are used extensively, but for many structures in the engineering of high-rise buildings, aerospace systemic engineerings, marine oil platforms etc, a large amount of calculation is still needed. An improved hybrid interface substructural component modal synthesis method(HISCMSM) is proposed. The parametric model of the mistuned blisk is built by the improved HISCMSM. The double coordinating conditions of the displacement and the force are introduced to ensure the computational accuracy. Compared with the overall structure finite element model method(FEMM), the computational time is shortened by23.86%–31.56%and the modal deviation is 0.002%–0.157% which meets the requirement of the computational accuracy. It is faster 4.46%–10.57% than the classical HISCMSM. So the improved HISCMSM is better than the classical HISCMSM and the overall structure FEMM. Meanwhile, the frequency and the modal shape are researched, considering the factors including rotational speed, gas temperature and geometry size. The strong localization phenomenon of the modal shape’s the maximum displacement and the maximum stress is observed in the second frequency band and it is the most sensitive in the frequency veering. But the localization phenomenon is relatively weak in 1st and the 3d frequency band. The localization of the modal shape is more serious under the condition of the geometric dimensioning mistuned. An improved HISCMSM is proposed, the computational efficiency of the mistuned blisk can be increased observably by this method.

  4. Natural vibration dynamics of Rainbow Bridge, Utah

    Science.gov (United States)

    Moore, J. R.; Thorne, M. S.; Wood, J. R.; Doyle, S.; Stanfield, E.; White, B.

    2015-12-01

    We measured resonant frequencies of Rainbow Bridge, Utah, one of the world's longest rock spans, during a field experiment recording ambient vibration data. Measurements were generated over 20 hours on March 23-24, 2015 using two broadband three-component seismometers placed on the bridge, and compared to concurrent data from nearby reference stations 20 and 220 m distant. We identified seven distinct modes of vibration for Rainbow Bridge between 1 and 6 Hz. Data for each resonant frequency was then analyzed to determine the frequency-dependent polarization vector in an attempt to clarify mode shapes; e.g. the fundamental mode represents out-of-plane horizontal flexure. We compared experimental data to results of 3D numerical modal analysis, using a new photogrammetric model of Rainbow Bridge generated in this study imported into COMSOL Multiphysics. Results compare well with measured data for seven of the first eight modeled modes, matching vibrational frequencies and polarization orientations generally within 10%. Only predicted mode 6 was not explicitly apparent in our experimental data. Large site-to-reference spectral ratios resolved from experimental data indicate high amplification on the bridge as compared to nearby bedrock.

  5. A probabilistic bridge safety evaluation against floods.

    Science.gov (United States)

    Liao, Kuo-Wei; Muto, Yasunori; Chen, Wei-Lun; Wu, Bang-Ho

    2016-01-01

    To further capture the influences of uncertain factors on river bridge safety evaluation, a probabilistic approach is adopted. Because this is a systematic and nonlinear problem, MPP-based reliability analyses are not suitable. A sampling approach such as a Monte Carlo simulation (MCS) or importance sampling is often adopted. To enhance the efficiency of the sampling approach, this study utilizes Bayesian least squares support vector machines to construct a response surface followed by an MCS, providing a more precise safety index. Although there are several factors impacting the flood-resistant reliability of a bridge, previous experiences and studies show that the reliability of the bridge itself plays a key role. Thus, the goal of this study is to analyze the system reliability of a selected bridge that includes five limit states. The random variables considered here include the water surface elevation, water velocity, local scour depth, soil property and wind load. Because the first three variables are deeply affected by river hydraulics, a probabilistic HEC-RAS-based simulation is performed to capture the uncertainties in those random variables. The accuracy and variation of our solutions are confirmed by a direct MCS to ensure the applicability of the proposed approach. The results of a numerical example indicate that the proposed approach can efficiently provide an accurate bridge safety evaluation and maintain satisfactory variation.

  6. Using rotating liquid bridges as accelerometers

    Energy Technology Data Exchange (ETDEWEB)

    Montanero, J.M. [Universidad de Extremadura, Badajoz (Spain). Dept. de Electronica e Ingenieria Electromecanica; Cabezas, G.; Acero, J.; Zayas, F.

    1999-07-01

    Liquid bridges have recently been proposed as fluid accelerometers that could be used to measure very small inertial forces under microgravity conditions [Meseguer et al., microgravity sci. technol. IX/2 (1996)]. The essential idea is to infer the values of such inertial forces from the liquid bridge interface contour, whose shape obviously depends on the values of such forces (apart from the bridge volume and the geometry of the supporting disks). Following a similar procedure, in this paper we explore the use of rotating axisymmetric liquid bridges to measure the residual axial gravity and the rotation rate of the liquid bridge regarded as a solid body. In light off the difficulties involved in performing experiments on Earth, the role of empirical data is played by an accurate numerical solution of the Young-Laplace equation. The values of both the axial gravity and angular speed are obtained by fitting the approximate analytical expressions derived in this paper to the numerical solution of the Young-Laplace equation. The comparison between the predicted and actual values of the variables of interest shows a satisfactory agreement, supporting the suitability of the procedure. (orig.)

  7. Heavy Vehicles on Minor Highway Bridges

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Nielsen, Søren R. K.; Enevoldsen, I.

    of heavier trucks moving at larger speeds, and partly because the authorities want to permit transportation of special heavy goods at a larger part of the road net. These needs will in many cases cause the strengthening of the bridges becomes necessary. In order to keep the expenses of such strengthening...... projects at a minimum, it is necessary to perform accurate estimates of the dynamic amplification factor (defined as the dynamic load effect divided by the static load effect from the vehicles), so this quantity is neither over- nor underestimated. The principal aims of the present paper are to establish...... the numerical models for the mathematical models of the vehicles and the bridge from which the load amplification factors can be estimated assuming that the dynamic parameters of the vehicles and the modal parameters of the bridge are known....

  8. Ergonomic aspects of automation in navigation bridges.

    Science.gov (United States)

    Lazet, A; Walraven, P L

    1971-06-01

    New ergonomic questions arise from the tendency toward increasing automation in maritime operations. Direct control of engines and rudder from the bridge promises improved ship control, provided that the operator can really exploit the technical improvements. To make such direct control most efficient, good ergonomic design is essential. A series of designs of navigation bridges is used to illustrate typical problems and situations. The building of full scale mock-ups of complete bridges is essential in order to handle the design as an integrated problem and to simulate the work situation. Such static mock-ups have been shown to be extremely useful in the discussion between builder, future user and adviser. An extension to dynamic simulation is necessary in order to study the actual work conditions in a new design.

  9. Influence of Icing on Bridge Cable Aerodynamics

    DEFF Research Database (Denmark)

    Koss, Holger; Frej Henningsen, Jesper; Olsen, Idar

    2013-01-01

    In recent years the relevance of ice accretion for wind-induced vibration of structural bridge cables has been recognised and became a subject of research in bridge engineering. Full-scale monitoring and observation indicate that light precipitation at moderate low temperatures between zero and -5......°C may lead to large amplitude vibrations of bridge cables under wind action. For the prediction of aerodynamic instability quasi-steady models have been developed estimating the cable response magnitude based on structural properties and aerodynamic force coefficients for drag, lift and torsion....... The determination of these force coefficients require a proper simulation of the ice layer occurring under the specific climatic conditions, favouring real ice accretion over simplified artificial reproduction. The work presented in this paper was performed to study the influence of ice accretion on the aerodynamic...

  10. Stability of dynamic response of suspension bridges

    Science.gov (United States)

    Capsoni, Antonio; Ardito, Raffaele; Guerrieri, Andrea

    2017-04-01

    The potential occurrence of internal parametric resonance phenomena has been recently indicated as a potential contributory cause of the appearance of critical dynamic states in long-span suspension bridges. At the same time, suspension bridges, in view of their flexibility, are prone to aeroelastic response, such as vortex shedding, torsional divergence and flutter. In this paper, a non-linear dynamic model of a suspension bridge is devised, with the purpose of providing a first attempt toward a unified framework for the study of aeroelastic and internal resonance instabilities. Inspired by the pioneering work of Herrmann and Hauger, the analyses have been based on a linearized formulation that is able to represent the main structural non-linear effects and the coupling given by aerodynamic forces. The results confirm that the interaction between aeroelastic effects and non-linear internal resonance leads to unstable conditions for wind speeds which can be lower than the critical threshold for standard aeroelastic predictions.

  11. Building bridges within the bacterial chromosome.

    Science.gov (United States)

    Song, Dan; Loparo, Joseph J

    2015-03-01

    All organisms must dramatically compact their genomes to accommodate DNA within the cell. Bacteria use a set of DNA-binding proteins with low sequence specificity called nucleoid-associated proteins (NAPs) to assist in chromosome condensation and organization. By bending or bridging DNA, NAPs also facilitate chromosome segregation and regulate gene expression. Over the past decade, emerging single-molecule and chromosome conformation capture techniques have investigated the molecular mechanisms by which NAPs remodel and organize the bacterial chromosome. In this review we describe how such approaches reveal the biochemical mechanisms of three NAPs that are believed to facilitate DNA bridging: histone-like nucleoid structuring protein (H-NS), ParB, and structural maintenance of chromosomes (SMC). These three proteins form qualitatively different DNA bridges, leading to varied effects on transcription and chromosome segregation.

  12. Fast Hough transform for automatic bridge extraction

    Science.gov (United States)

    Hao, Qiwei; Chen, Xiaomei; Ni, Guoqiang; Zhang, Huaili

    2008-03-01

    In this paper, a new method to recognize bridge in the complicated background is presented. The algorithm takes full advantages of the characteristics of the bridge image. Firstly, the image is preprocessed and the object edges are extracted. Then according to the limitations of traditional Hough transform (HT), the extraction method of the image line segment characteristic of HT is improved, which eliminates spurious peaks on the basis of global and local thresholds, discriminates the position relation between two straight line segments, and merges segments with near endpoints, etc. Experiments show that this algorithm is more precise and efficient than traditional HT, moreover it can provide a complete description of the bridge in a complicated background.

  13. MINERAL BRIDGES OF NACRE AND ITS EFFECTS

    Institute of Scientific and Technical Information of China (English)

    宋凡; 白以龙

    2001-01-01

    Nacre, or mother-of-pearl, is a kind of composites of aragonite platelets sandwiched between organic materials. Its excellent mechanical properties are thought to stem from the microarchitecture that is traditionally described as a "brick and mortar" arrangement. In this paper, a new microstructure, referred to as mineral bridge in the biomineralization, is directly observed in the organic matrix layers (mortar) of nacre. This is an indication that the organic matrix layer of nacre should be treated as a three-dimensional interface and the microarchitecture of nacre ought to be considered as a "brick-bridge-mortar" structure rather than the traditional one. Experiments and analyses show that the mineral bridges not only improve the mechanical properties of the organic matrix layers but also play an important role in the pattern of the crack extension in nacre.

  14. Operational modal analysis of road-rail bridge

    OpenAIRE

    Cardoso M.; Sampaio R. A. C.; de Souza R. M.; Silva E.

    2015-01-01

    In this paper, we describe an Operational Modal Analysis (OMA) of the Bridge over the Tocantins River, a composite road-rail bridge located in the city of Marabá, state of Pará, northern Brazil. The bridge is part of the Carajás Railway, which is used by VALE Company to transport iron ore from “Serra dos Carajás”, the largest mineral reserve of the planet. The bridge has a length of 2310m, being the second longest road-rail bridge in Brazil. The study focused on the bridge central span (with ...

  15. Dragon bridge - the world largest dragon-shaped (ARCH steel bridge as element of smart city

    Directory of Open Access Journals (Sweden)

    Chinh Luong Minh

    2016-01-01

    Full Text Available Dragon Bridge - The world’s largest dragon-shaped steel bridge, with an installation cost of $85 million USD, features 6 lanes for two separate directions, 666 meters of undulating steel in the shape of a dragon in the Ly Dynasty, the symbol of prosperity in Vietnamese culture. This unique and beautifully lit bridge, which also breathes fire and sprays water. It’s the purposeful integration of the lighting hardware articulates the dragon’s form, and the fire-breathing dragon head. This project transcends the notion of monumental bridge with dynamic colour-changing lighting, creating an iconic sculpture in the skyline that is both reverent and whimsical. The signature feature of the bridge was the massive undulating support structure resembling a dragon flying over the river. The dragon is prominent in Vietnamese culture as a symbol of power and nobility. Dragon Bridge stands out as a model of innovation. It has received worldwide attention in the design community and from the global media for its unique arch support system. Dragon Bridge serves as an example of how aesthetic quality of a design can serve cultural, economic and functional purposes. The article presents design solutions of the object and the evaluation of the technical condition before putting the facility into service.

  16. The seismic response of concrete arch bridges (with focus on the Bixby Creek bridge Carmel, California)

    Energy Technology Data Exchange (ETDEWEB)

    Hoehler, M; McCallen, D; Noble, C

    1999-06-01

    The analysis, and subsequent retrofit, of concrete arch bridges during recent years has relied heavily on the use of computational simulation. For seismic analysis in particular, computer simulation, typically utilizing linear approximations of structural behavior, has become standard practice. This report presents the results of a comprehensive study of the significance of model sophistication (i.e. linear vs. nonlinear) and pertinent modeling assumptions on the dynamic response of concrete arch bridges. The study uses the Bixby Creek Bridge, located in California, as a case study. In addition to presenting general recommendations for analysis of this class of structures, this report provides an independent evaluation of the proposed seismic retrofit for the Bixby Creek Bridge. Results from the study clearly illustrate a reduction of displacement drifts and redistribution of member forces brought on by the inclusion of material nonlinearity. The analyses demonstrate that accurate modeling of expansion joints, for the Bixby Creek Bridge in particular, is critical to achieve representative modal and transient behavior. The inclusion of near-field displacement pulses in ground motion records was shown to significantly increase demand on the relatively softer, longer period Bixby Creek Bridge arch. Stiffer, shorter period arches, however, are more likely susceptible to variable support motions arising from the canyon topography typical for this class of bridges.

  17. Extracorporeal Life Support Bridge to Ventricular Assist Device: The Double Bridge Strategy.

    Science.gov (United States)

    Marasco, Silvana F; Lo, Casey; Murphy, Deirdre; Summerhayes, Robyn; Quayle, Margaret; Zimmet, Adam; Bailey, Michael

    2016-01-01

    In patients requiring left ventricular assist device (LVAD) support, it can be difficult to ascertain suitability for long-term mechanical support with LVAD and eventual transplantation. LVAD implantation in a shocked patient is associated with increased morbidity and mortality. Interest is growing in the utilization of extracorporeal life support (ECLS) as a bridge-to-bridge support for these critically unwell patients. Here, we reviewed our experience with ECLS double bridging. We hypothesized that ECLS double bridging would stabilize end-organ dysfunction and reduce ventricular assist device (VAD) implant perioperative mortality. We conducted a retrospective review of prospectively collected data for 58 consecutive patients implanted with a continuous-flow LVAD between January 2010 and December 2013 at The Alfred Hospital, Melbourne, Victoria, Australia. Twenty-three patients required ECLS support pre-LVAD while 35 patients underwent LVAD implantation without an ECLS bridge. Preoperative morbidity in the ECLS bridge group was reflected by increased postoperative intensive care duration, blood loss, blood product use, and postoperative renal failure, but without negative impact upon survival when compared with the no ECLS group. ECLS stabilization improved end-organ function pre-VAD implant with significant improvements in hepatic and renal dysfunction. This series demonstrates that the use of ECLS bridge to VAD stabilizes end-organ dysfunction and reduces VAD implant perioperative mortality from that traditionally reported in these "crash and burn" patients.

  18. Stability of a liquid bridge under vibration

    Science.gov (United States)

    Benilov, E. S.

    2016-06-01

    We examine the stability of a vertical liquid bridge between two vertically vibrating, coaxial disks. Assuming that the vibration amplitude and period are much smaller than the mean distance between the disks and the global timescale, respectively, we employ the method of multiple scales to derive a set of asymptotic equations. The set is then used to examine the stability of a bridge of an almost cylindrical shape. It is shown that, if acting alone, gravity is a destabilizing influence, whereas vibration can weaken it or even eliminate altogether. Thus, counter-intuitively, vibration can stabilize an otherwise unstable capillary structure.

  19. A Bridge Deflection Monitoring with GPS

    Science.gov (United States)

    Figurski, M.; Gałuszkiewicz, M.; Wrona, M.

    2007-01-01

    This paper introduces results of investigation carried on by The Applied Geomatics Section in Military University of Technology. Research includes possibilities of monitoring dynamic behavior of a bridge using high rate GPS data. Whole event was executed with collaboration of The Road and Bridge Management and The Warsaw Geodesy Company. Interdisciplinary approach with this project allows authors to get reliable information about investigating constructions and their respond for true traffic loading detected by GPS receivers. Way of compute data and used software (TRACK) are also shown in this paper.

  20. Planar Hall effect bridge magnetic field sensors

    DEFF Research Database (Denmark)

    Henriksen, A.D.; Dalslet, Bjarke Thomas; Skieller, D.H.

    2010-01-01

    Until now, the planar Hall effect has been studied in samples with cross-shaped Hall geometry. We demonstrate theoretically and experimentally that the planar Hall effect can be observed for an exchange-biased ferromagnetic material in a Wheatstone bridge topology and that the sensor signal can...... be significantly enhanced by a geometric factor. For the samples in the present study, we demonstrate an enhancement of the sensor output by a factor of about 100 compared to cross-shaped sensors. The presented construction opens a new design and application area of the planar Hall effect, which we term planar...... Hall effect bridge sensors....