Science.gov

Sample records for bridge design

  1. Virtual Bridge Design Challenge

    ERIC Educational Resources Information Center

    Mitts, Charles R.

    2013-01-01

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

  2. Virtual Bridge Design

    ERIC Educational Resources Information Center

    Bisogno, Janet; JeanPierre, Bobby

    2008-01-01

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

  3. Seismic design guidelines for highway bridges

    NASA Astrophysics Data System (ADS)

    Mayes, R. L.; Sharpe, R. L.

    1981-10-01

    Guidelines for the seismic design of highway bridges are given. The guidelines are the recommendations of a team of nationally recognized experts which included consulting engineers, academicians, State highway, and Federal agency representatives from throughout the United States. The guidelines are comprehensive in nature and they embody several new concepts which are significant departures from existing design provisions. An extensive commentary documenting the basis for the guidelines and an example demonstrating their use are included. A draft of the guidelines was used to seismically redesign twenty-one bridges. A summary of the redesigns is included.

  4. A modular steel freeway bridge: design concept and earthquake resistance.

    PubMed

    Wattenburg, W H; McCallen, D B; Murray, R C

    1995-04-14

    A modular multilane steel freeway bridge has been constructed from surplus railroad flatcar decks. It can be erected on-site in a few days' time. It has been built and static-load tested for emergency freeway bridge repair. This inexpensive modular bridge may also have broad application around the world for low-cost bridges in areas where funds are limited. On the basis of static-load testing performed by the California Department of Transportation and computer dynamic analysis, this simple modular-design concept has the potential of providing a strong bridge that can withstand the severe aftershocks expected immediately after a major earthquake. PMID:17814794

  5. Teaching Elements and Principles of Bridge Design

    ERIC Educational Resources Information Center

    Beck, Charles

    2005-01-01

    Bridge construction is a popular classroom activity. However, the basic principles of tension, compression, and counterbalance are not always clearly represented and defined. The common materials used to construct model bridges, such as straws, toothpicks, Legos[TM], and building blocks, are often too flexible or stationary to demonstrate the…

  6. Optimum design of concrete cable-stayed bridges

    NASA Astrophysics Data System (ADS)

    Martins, Alberto M. B.; Simões, Luís M. C.; Negrão, João H. J. O.

    2016-05-01

    The design of cable-stayed bridges involves a significant number of design variables and design objectives. The concrete cable-stayed bridge optimization is formulated here as a multi-objective optimization problem with objectives of minimum cost, minimum deflections and minimum stresses. A numerical method is developed to obtain the optimum design of such structures. This numerical method includes: structural analysis, sensitivity analysis and optimization. The structural analysis accounts for all the relevant effects (concrete time-dependent effects, construction stages and geometrical nonlinear effects). The structural response to changes in the design variables is achieved by a discrete direct sensitivity analysis procedure, and an entropy-based approach was used for structural optimization. The features and applicability of the proposed method are demonstrated by numerical examples concerning the optimization of a real-sized concrete cable-stayed bridge.

  7. A Bridge for Accelerating Materials by Design

    SciTech Connect

    Sumpter, Bobby G.; Vasudevan, Rama K.; Potok, Thomas E.; Kalinin, Sergei V.

    2015-11-25

    Recent technical advances in the area of nanoscale imaging, spectroscopy, and scattering/diffraction have led to unprecedented capabilities for investigating materials structural, dynamical and functional characteristics. In addition, recent advances in computational algorithms and computer capacities that are orders of magnitude larger/faster have enabled large-scale simulations of materials properties starting with nothing but the identity of the atomic species and the basic principles of quantum- and statistical-mechanics and thermodynamics. Along with these advances, an explosion of high-resolution data has emerged. This confluence of capabilities and rise of big data offer grand opportunities for advancing materials sciences but also introduce several challenges. In this editorial we identify challenges impeding progress towards advancing materials by design (e.g., the design/discovery of materials with improved properties/performance), possible solutions, and provide examples of scientific issues that can be addressed by using a tightly integrated approach where theory and experiments are linked through big-deep data.

  8. A Bridge for Accelerating Materials by Design

    DOE PAGESBeta

    Sumpter, Bobby G.; Vasudevan, Rama K.; Potok, Thomas E.; Kalinin, Sergei V.

    2015-11-25

    Recent technical advances in the area of nanoscale imaging, spectroscopy, and scattering/diffraction have led to unprecedented capabilities for investigating materials structural, dynamical and functional characteristics. In addition, recent advances in computational algorithms and computer capacities that are orders of magnitude larger/faster have enabled large-scale simulations of materials properties starting with nothing but the identity of the atomic species and the basic principles of quantum- and statistical-mechanics and thermodynamics. Along with these advances, an explosion of high-resolution data has emerged. This confluence of capabilities and rise of big data offer grand opportunities for advancing materials sciences but also introduce several challenges.more » In this editorial we identify challenges impeding progress towards advancing materials by design (e.g., the design/discovery of materials with improved properties/performance), possible solutions, and provide examples of scientific issues that can be addressed by using a tightly integrated approach where theory and experiments are linked through big-deep data.« less

  9. Zinc Oxide Nanorod Based Ultraviolet Detectors with Wheatstone Bridge Design

    NASA Astrophysics Data System (ADS)

    Vasudevan, Arun

    This research work, for the first time, investigated metal semiconductor-metal (MSM) zine oxide (ZnO) nanorod based ultra-violet (UV) detectors having a Wheatstone bridge design with a high responsivity at room temperature and above, as well as a responsivity that was largely independent of the change in ambient conditions. The ZnO nanorods which acted as the sensing element of the detector were grown by a chemical growth technique. Studies were conducted to determine the effects on ZnO nanorod properties by varying the concentration of the chemicals used for the rod growth. These studies showed how the rod diameter and the deposition of ZnO nanorods from the solution was controlled by varying the concentration of the chemicals used for the rod growth. Conventional MSM UV detectors were fabricated with ZnO nanorods grown under optimized conditions to determine the dependence of UV response on electrode dimension and rod dimension. These studies gave insights into the dependence of UV response on the width of the electrode, spacing between the electrodes, density of the rod growth, and length and diameter of the rods. The UV responsivity was affected by varying the number of times the seed layer was spin coated, by varying the spin speed of seed layer coating and by varying the annealing temperature of the seed and rod. Based on these studies, optimum conditions for the fabrication of Wheatstone bridge UV ZnO nanorod detectors were determined. The Wheatstone bridge ZnO nanorod UV detectors were fabricated in three different configurations, namely, symmetric, asymmetric, and quasi-symmetric. The transient responses of the symmetric, asymmetric and quasi-symmetric configurations at room temperature and above showed how the response stability differed. At high temperature the responsivity of quasi-symmetric Wheatstone bridge detector configuration did not drop after saturation and the responsivity drifted by 17% to 25% from the room temperature response

  10. Basis of Design and Seismic Action for Long Suspension Bridges: the case of the Messina Strait Bridge

    SciTech Connect

    Bontempi, Franco

    2008-07-08

    The basis of design for complex structures like suspension bridges is reviewed. Specific attention is devoted to seismic action and to the performance required and to the connected structural analysis. Uncertainty is specially addressed by probabilistic and soft-computing techniques. The paper makes punctual reference to the work end the experience developed during the last years for the re-design of the Messina Strait Bridge.

  11. Bridging the gap between building science and design studios

    SciTech Connect

    Papamichael, Konstantinos; Pal, Vineeta

    2002-02-06

    Design studios and building science courses have been conducted independent of each other, mainly due to a lack of tools that allow quick and easy consideration of building science criteria, such as comfort and energy requirements, during the design process. Existing tools are not user-friendly and their use requires significant effort in gaining familiarity with the input requirements, understanding the modeling assumptions and interpreting the output. This paper is about the Building Design Advisor (BDA), an evolving computer-based tool intended to bridge the gap between design studios and building science considerations by addressing the above-mentioned limitations of existing tools. BDA allows automatic preparation of input files to multiple simulation tools while the user is working in a CAD environment. BDA automatically activates the relevant simulation tools when the user selects performance parameters to be computed and provides the results in a graphical form, allowing comparison of multiple design options with respect to multiple performance criteria. The paper includes considerations for the use of the BDA in the design studio and ends with a description of the current development efforts and future plans.

  12. Design and performance evaluation of the NIST digital impedance bridge

    SciTech Connect

    Waltrip, B.C.; Oldham, N.M.

    1994-12-31

    An impedance bridge that compares two-terminal standard inductors to characterized resistors is described. A dual-channel digitally synthesized source and sampling digital multimeter are used to generate and measure relevant bridge signals. A linear interpolation algorithm is used to autocalibrate the bridge to a 1 nF air-dielectric capacitor An intercomparison of the new bridge with existing measurement standards in the low audio frequency range for inductors from 1 mH to 10 H will be reported.

  13. 23 CFR 661.53 - What standards should be used for bridge design?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... life consistent with 25 CFR part 170, Subpart D, Appendix B and 23 CFR part 625. (b) Rehabilitation—Bridges to be rehabilitated, as a minimum, should conform to the standards of 23 CFR part 625, Design... 23 Highways 1 2011-04-01 2011-04-01 false What standards should be used for bridge design?...

  14. 23 CFR 661.53 - What standards should be used for bridge design?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... life consistent with 25 CFR part 170, Subpart D, Appendix B and 23 CFR part 625. (b) Rehabilitation—Bridges to be rehabilitated, as a minimum, should conform to the standards of 23 CFR part 625, Design... 23 Highways 1 2013-04-01 2013-04-01 false What standards should be used for bridge design?...

  15. 23 CFR 661.53 - What standards should be used for bridge design?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... life consistent with 25 CFR part 170, Subpart D, Appendix B and 23 CFR part 625. (b) Rehabilitation—Bridges to be rehabilitated, as a minimum, should conform to the standards of 23 CFR part 625, Design... 23 Highways 1 2010-04-01 2010-04-01 false What standards should be used for bridge design?...

  16. 23 CFR 661.53 - What standards should be used for bridge design?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... life consistent with 25 CFR part 170, Subpart D, Appendix B and 23 CFR part 625. (b) Rehabilitation—Bridges to be rehabilitated, as a minimum, should conform to the standards of 23 CFR part 625, Design... 23 Highways 1 2014-04-01 2014-04-01 false What standards should be used for bridge design?...

  17. 23 CFR 661.53 - What standards should be used for bridge design?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... life consistent with 25 CFR part 170, Subpart D, Appendix B and 23 CFR part 625. (b) Rehabilitation—Bridges to be rehabilitated, as a minimum, should conform to the standards of 23 CFR part 625, Design... 23 Highways 1 2012-04-01 2012-04-01 false What standards should be used for bridge design?...

  18. Next generation seismic fragility curves for California bridges incorporating the evolution in seismic design philosophy

    NASA Astrophysics Data System (ADS)

    Ramanathan, Karthik Narayan

    Quantitative and qualitative assessment of the seismic risk to highway bridges is crucial in pre-earthquake planning, and post-earthquake response of transportation systems. Such assessments provide valuable knowledge about a number of principal effects of earthquakes such as traffic disruption of the overall highway system, impact on the regions’ economy and post-earthquake response and recovery, and more recently serve as measures to quantify resilience. Unlike previous work, this study captures unique bridge design attributes specific to California bridge classes along with their evolution over three significant design eras, separated by the historic 1971 San Fernando and 1989 Loma Prieta earthquakes (these events affected changes in bridge seismic design philosophy). This research developed next-generation fragility curves for four multispan concrete bridge classes by synthesizing new knowledge and emerging modeling capabilities, and by closely coordinating new and ongoing national research initiatives with expertise from bridge designers. A multi-phase framework was developed for generating fragility curves, which provides decision makers with essential tools for emergency response, design, planning, policy support, and maximizing investments in bridge retrofit. This framework encompasses generational changes in bridge design and construction details. Parameterized high-fidelity three-dimensional nonlinear analytical models are developed for the portfolios of bridge classes within different design eras. These models incorporate a wide range of geometric and material uncertainties, and their responses are characterized under seismic loadings. Fragility curves were then developed considering the vulnerability of multiple components and thereby help to quantify the performance of highway bridge networks and to study the impact of seismic design principles on the performance within a bridge class. This not only leads to the development of fragility relations

  19. Design Of Bridges For Non Synchronous Seismic Motion

    SciTech Connect

    Nuti, Camillo; Vanzi, Ivo

    2008-07-08

    this paper aims to develop and validate structural design criteria which account for the effects of earthquakes spatial variability. In past works [1, 2] the two simplest forms of this problem were dealt with: differential displacements between two points belonging to the soil or to two single degree of freedom structures. Seismic action was defined according to EC8 [3]; the structures were assumed linear elastic sdof oscillators. Despite this problem may seem trivial, existing codes models appeared improvable on this aspect. For the differential displacements of two points on the ground, these results are now validated and generalized using the newly developed response spectra contained in the new seismic Italian code [4]; the resulting code formulation is presented. Next, the problem of statistically defining the differential displacement among any number of points on the ground (which is needed for continuos deck bridges) is approached, and some preliminary results shown. It is also shown that the current codes (e.g. EC8) rules may be improved on this aspect.

  20. Design and implementation of the ESL compact range underhung bridge crane

    NASA Technical Reports Server (NTRS)

    Shamansky, H. T.; Dominek, A. K.; Burnside, W. D.

    1987-01-01

    As the indoor compact range technology has continued to increase, the need to handle larger and heavier targets has also increased. This need for target lifting and handling prompted the feasibility study of the use of an underhung bridge crane to be installed in the ESL (ElectroScience Laboratory, Ohio State University) compact range. This report documents both the design of the underhung bridge crane that was installed and the implementation of the design in the actual installation of the crane.

  1. Computational design of donor-bridge-acceptor systems exhibiting pronounced quantum interference effects.

    PubMed

    Gorczak, Natalie; Renaud, Nicolas; Galan, Elena; Eelkema, Rienk; Siebbeles, Laurens D A; Grozema, Ferdinand C

    2016-03-01

    Quantum interference is a well-known phenomenon that dictates charge transport properties of single molecule junctions. However, reports on quantum interference in donor-bridge-acceptor molecules are scarce. This might be due to the difficulties in meeting the conditions for the presence of quantum interference in a donor-bridge-acceptor system. The electronic coupling between the donor, bridge, and acceptor moieties must be weak in order to ensure localised initial and final states for charge transfer. Yet, it must be strong enough to allow all bridge orbitals to mediate charge transfer. We present the computational route to the design of a donor-bridge-acceptor molecule that features the right balance between these contradicting requirements and exhibits pronounced interference effects. PMID:26878200

  2. Causeway and bridge design to reduce roadway contaminant runoff to a saltmarsh ecosystem

    SciTech Connect

    Leitman, P.A.; Ross, P.E.

    1995-12-31

    At the insistence of the local fishermen and landowners the Isle of Palms connector (Charleston, South Carolina) was built with a unique set of environmental safeguards so that the saltmarsh beneath the bridge would remain uncontaminated. This study evaluates the effectiveness of the bridge, in order to judge the suitability of the design for other areas. A two kilometer causeway over the marsh has catch pans to hold runoff, except that a heavy rain causes the pans to overflow. A one kilometer span over the Intracoastal waterway has pipes that redirect the runoff into gravel lined spoils. The bridge was monitored quarterly from January to December 1994. Extensive testing was performed during October 1994 to compare sites around the bridge and within the watershed to a pristine site and a to highly contaminated site. Sediment and water samples were tested with the Microtox{reg_sign} bioluminescence assay and a Latuca sativa (lettuce) seed germination and growth assay. Sediment samples were also tested with a Mercenaria mercenaria (littleneck clam) growth bioassay. Benthic community structure was analyzed for sites around the bridge. While very few statistically significant instances of toxicity were found, there are some trends that make it apparent that the bridge runoff may have some effects. There is no apparent accumulation of toxic contaminants from the pan overflow in sediments beneath the bridge, and this bridge design should ameliorate the effects of bridge runoff in almost any area. Future research using chemical analysis of the fate and transport of contaminants within the bridge and the surrounding area is suggested.

  3. Optimum design of bridges with superelastic-friction base isolators against near-field earthquakes

    NASA Astrophysics Data System (ADS)

    Ozbulut, Osman E.; Hurlebaus, Stefan

    2010-04-01

    The seismic response of a multi-span continuous bridge isolated with novel superelastic-friction base isolator (S-FBI) is investigated under near-field earthquakes. The isolation system consists of a flat steel-Teflon sliding bearing and a superelastic NiTi shape memory alloy (SMA) device. Sliding bearings limit the maximum seismic forces transmitted to the superstructure to a certain value that is a function of friction coefficient of sliding interface. Superelastic SMA device provides restoring capability to the isolation system together with additional damping characteristics. The key design parameters of an S-FBI system are the natural period of the isolated, yielding displacement of SMA device, and the friction coefficient of the sliding bearings. The goal of this study is to obtain optimal values for each design parameter by performing sensitivity analyses of the isolated bridge. First, a three-span continuous bridge is modeled as a two-degrees-of-freedom with S-FBI system. A neuro-fuzzy model is used to capture rate-dependent nonlinear behavior of SMA device. A time-dependent method which employs wavelets to adjust accelerograms to match a target response spectrum with minimum changes on the other characteristics of ground motions is used to generate ground motions used in the simulations. Then, a set of nonlinear time history analyses of the isolated bridge is performed. The variation of the peak response quantities of the isolated bridge is shown as a function of design parameters. Also, the influence of temperature variations on the effectiveness of S-FBI system is evaluated. The results show that the optimum design of the isolated bridge with S-FBI system can be achieved by a judicious specification of design parameters.

  4. Design for minimizing fracture risk of all-ceramic cantilever dental bridge.

    PubMed

    Zhang, Zhongpu; Zhou, Shiwei; Li, Eric; Li, Wei; Swain, Michael V; Li, Qing

    2015-01-01

    Minimization of the peak stresses and fracture incidence induced by mastication function is considered critical in design of all-ceramic dental restorations, especially for cantilever fixed partial dentures (FPDs). The focus of this study is on developing a mechanically-sound optimal design for all-ceramic cantilever dental bridge in a posterior region. The topology optimization procedure in association with Extended Finite Element Method (XFEM) is implemented here to search for the best possible distribution of porcelain and zirconia materials in the bridge structure. The designs with different volume fractions of zirconia are considered. The results show that this new methodology is capable of improving FPD design by minimizing incidence of crack in comparison with the initial design. Potentially, it provides dental technicians with a new design tool to develop mechanically sound cantilever fixed partial dentures for more complicated clinical situation. PMID:26405963

  5. Designing a bridge for consciousness: are criteria for a unification of approaches feasible?

    PubMed

    Miller, D W

    2000-01-01

    Different intrinsic rules of functioning for body and mind are overemphasized by the mutually exclusive methods of investigation in both consciousness and the sciences. Classical science, alternative and complementary healing, quantum physics, and metaphysics all take drastically different approaches to consciousness research. A bridge is needed to restore the conceptual unity of mind-body. However, the construction of such a bridge paradoxically must rely on consciousness for information. The construction company (Consciousness, Inc.) therefore becomes means and end in the design of the bridge. This piece argues that the methods of each discipline contain research tools and resources to create a bridge that satisfies a unified multidimensional and multidisciplinary conception. The piece further suggests that the framework of the bridge must place consciousness as a partner to physiology in the evolutionary trajectory of life, since problems of survival are a primary consideration in the activity of both. Finally, the piece develops six criteria by which to evaluate the effectiveness of any construction design. PMID:10835764

  6. Learning Axes and Bridging Tools in a Technology-Based Design for Statistics

    ERIC Educational Resources Information Center

    Abrahamson, Dor; Wilensky, Uri

    2007-01-01

    We introduce a design-based research framework, "learning axes and bridging tools," and demonstrate its application in the preparation and study of an implementation of a middle-school experimental computer-based unit on probability and statistics, "ProbLab" (Probability Laboratory, Abrahamson and Wilensky 2002 [Abrahamson, D., & Wilensky, U.…

  7. Engineering Design Processes in Seventh-Grade Classrooms: Bridging the Engineering Education Gap

    ERIC Educational Resources Information Center

    English, Lyn D.; Hudson, Peter B.; Dawes, Les

    2012-01-01

    This paper reports on some findings from the first year of a three-year longitudinal study, in which seventh- to ninth-graders were introduced to engineering education. Specifically, the paper addresses students' responses to an initial design activity involving bridge construction, which was implemented at the end of seventh grade. This paper…

  8. An Ontology-Based Framework for Bridging Learning Design and Learning Content

    ERIC Educational Resources Information Center

    Knight, Colin, Gasevic, Dragan; Richards, Griff

    2006-01-01

    The paper describes an ontology-based framework for bridging learning design and learning object content. In present solutions, researchers have proposed conceptual models and developed tools for both of those subjects, but without detailed discussions of how they can be used together. In this paper we advocate the use of ontologies to explicitly…

  9. The Belizean Bridge Activity.

    ERIC Educational Resources Information Center

    Murfin, Brian

    2000-01-01

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

  10. Monogroove heat pipe design: Insulated liquid channel with bridging wick

    NASA Technical Reports Server (NTRS)

    Alario, J. P.; Brown, R. F.; Kosson, R. L. (Inventor)

    1985-01-01

    A screen mesh artery supported concentrically within the evaporator section of a heat pipe liquid channel retains liquid in the channel. Continued and uniform liquid feed to the heat pipe evaporation section (20) during periods of excessive heat transfer is assured. The overall design provides high evaporation and condensation film coefficients for the working fluid by means of the circumferential grooves in the walls of the vapor channel, while not interfering with the overall heat transport capability of the axial groove. The design has particular utility in zero-g environments.

  11. Affordability Engineering: Bridging the Gap Between Design and Cost

    NASA Technical Reports Server (NTRS)

    Reeves, J. D.; DePasquale, Dominic; Lim, Evan

    2010-01-01

    Affordability is a commonly used term that takes on numerous meanings depending on the context used. Within conceptual design of complex systems, the term generally implies comparisons between expected costs and expected resources. This characterization is largely correct, but does not convey the many nuances and considerations that are frequently misunderstood and underappreciated. In the most fundamental sense, affordability and cost directly relate to engineering and programmatic decisions made throughout development programs. Systems engineering texts point out that there is a temporal aspect to this relationship, for decisions made earlier in a program dictate design implications much more so than those made during latter phases. This paper explores affordability engineering and its many sub-disciplines by discussing how it can be considered an additional engineering discipline to be balanced throughout the systems engineering and systems analysis processes. Example methods of multidisciplinary design analysis with affordability as a key driver will be discussed, as will example methods of data visualization, probabilistic analysis, and other ways of relating design decisions to affordability results.

  12. A designed buried salt bridge modulates heterodimerization of a membrane peptide.

    PubMed

    Shinde, Sandip; Binder, Jennifer K; Goyal, Bhupesh; Woodrum, B; De Munari, Sonia; Levitus, Marcia; Ghirlanda, Giovanna

    2014-11-01

    Specific helix-helix interactions underpin the correct assembly of multipass membrane proteins. Here, we show that a designed buried salt bridge mediates heterodimer formation of model transmembrane helical peptides in a pH-dependent manner. The model peptides bear side chains functionalized with either a carboxylic acid or a primary amine within a hydrophobic segment. The association behavior was monitored by Förster resonance energy transfer, revealing that heterodimer formation is maximized at a pH close to neutrality (pH 6.5), at which each peptide is found in a charged state. In contrast, heterodimerization is disfavored at low and high values of pH, because either the carboxylic acid or the primary amine is present in its neutral state, thus preventing the formation of a salt bridge. These findings provide a blueprint for the design and modulation of protein-protein interactions in membrane proteins. PMID:25250823

  13. The Principle of the Micro-Electronic Neural Bridge and a Prototype System Design.

    PubMed

    Huang, Zong-Hao; Wang, Zhi-Gong; Lu, Xiao-Ying; Li, Wen-Yuan; Zhou, Yu-Xuan; Shen, Xiao-Yan; Zhao, Xin-Tai

    2016-01-01

    The micro-electronic neural bridge (MENB) aims to rebuild lost motor function of paralyzed humans by routing movement-related signals from the brain, around the damage part in the spinal cord, to the external effectors. This study focused on the prototype system design of the MENB, including the principle of the MENB, the neural signal detecting circuit and the functional electrical stimulation (FES) circuit design, and the spike detecting and sorting algorithm. In this study, we developed a novel improved amplitude threshold spike detecting method based on variable forward difference threshold for both training and bridging phase. The discrete wavelet transform (DWT), a new level feature coefficient selection method based on Lilliefors test, and the k-means clustering method based on Mahalanobis distance were used for spike sorting. A real-time online spike detecting and sorting algorithm based on DWT and Euclidean distance was also implemented for the bridging phase. Tested by the data sets available at Caltech, in the training phase, the average sensitivity, specificity, and clustering accuracies are 99.43%, 97.83%, and 95.45%, respectively. Validated by the three-fold cross-validation method, the average sensitivity, specificity, and classification accuracy are 99.43%, 97.70%, and 96.46%, respectively. PMID:26276996

  14. Design of an enhanced sensitivity FBG strain sensor and application in highway bridge engineering

    NASA Astrophysics Data System (ADS)

    Li, Litong; Zhang, Dongsheng; Liu, Hui; Guo, Yongxing; Zhu, Fangdong

    2014-06-01

    The theoretical design method of enhanced sensitivity fiber grating (FBG) strain sensors was given, and moreover high qualified strain sensors were developed and fabricated, whose sensing properties were good for practical applications. The strain sensor with cylindrical shell encapsulation contained three tubular structures, due to the uneven surface structure, in the area of the strain concentration, improving the sensitivity. It could achieve the embedment strain measurement and surface measurement and had the advantages of the easy installation. The good agreement was obtained between the measurements and theoretical simulation results. After each calibration test, twenty-four FBG strain sensors and six FBG temperature compensation sensors have been installed on the undersurface of the box girder of Diaoshuiyan bridge in Yongtaiwen highway. Finally, we built up a long-term structure health system for the highway bridge.

  15. Design and Characterization of a Peptide Mimotope of the HIV-1 gp120 Bridging Sheet

    PubMed Central

    Schiavone, Marco; Fiume, Giuseppe; Caivano, Antonella; de Laurentiis, Annamaria; Falcone, Cristina; Masci, Francesca Fasanella; Iaccino, Enrico; Mimmi, Selena; Palmieri, Camillo; Pisano, Antonio; Pontoriero, Marilena; Rossi, Annalisa; Scialdone, Annarita; Vecchio, Eleonora; Andreozzi, Concetta; Trovato, Maria; Rafay, Jan; Ferko, Boris; Montefiori, David; Lombardi, Angela; Morsica, Giulia; Poli, Guido; Quinto, Ileana; Pavone, Vincenzo; de Berardinis, Piergiuseppe; Scala, Giuseppe

    2012-01-01

    The Bridging Sheet domain of HIV-1 gp120 is highly conserved among the HIV-1 strains and allows HIV-1 binding to host cells via the HIV-1 coreceptors. Further, the bridging sheet domain is a major target to neutralize HIV-1 infection. We rationally designed four linear peptide epitopes that mimic the three-dimensional structure of bridging sheet by using molecular modeling. Chemically synthesized peptides BS3 and BS4 showed a fair degree of antigenicity when tested in ELISA with IgG purified from HIV+ broadly neutralizing sera while the production of synthetic peptides BS1 and BS2 failed due to their high degree of hydrophobicity. To overcome this limitation, we linked all four BS peptides to the COOH-terminus of GST protein to test both their antigenicity and immunogenicity. Only the BS1 peptide showed good antigenicity; however, no envelope specific antibodies were elicited upon mice immunization. Therefore we performed further analyses by linking BS1 peptide to the NH2-terminus of the E2 scaffold from the Geobacillus Stearothermophylus PDH complex. The E2-BS1 fusion peptide showed good antigenic results, however only one immunized rabbit elicited good antibody titers towards both the monomeric and oligomeric viral envelope glycoprotein (Env). In addition, moderate neutralizing antibodies response was elicited against two HIV-1 clade B and one clade C primary isolates. These preliminary data validate the peptide mimotope approach as a promising tool to obtain an effective HIV-1 vaccine. PMID:22754323

  16. Improved Simplified Methods for Effective Seismic Analysis and Design of Isolated and Damped Bridges in Western and Eastern North America

    NASA Astrophysics Data System (ADS)

    Koval, Viacheslav

    The seismic design provisions of the CSA-S6 Canadian Highway Bridge Design Code and the AASHTO LRFD Seismic Bridge Design Specifications have been developed primarily based on historical earthquake events that have occurred along the west coast of North America. For the design of seismic isolation systems, these codes include simplified analysis and design methods. The appropriateness and range of application of these methods are investigated through extensive parametric nonlinear time history analyses in this thesis. It was found that there is a need to adjust existing design guidelines to better capture the expected nonlinear response of isolated bridges. For isolated bridges located in eastern North America, new damping coefficients are proposed. The applicability limits of the code-based simplified methods have been redefined to ensure that the modified method will lead to conservative results and that a wider range of seismically isolated bridges can be covered by this method. The possibility of further improving current simplified code methods was also examined. By transforming the quantity of allocated energy into a displacement contribution, an idealized analytical solution is proposed as a new simplified design method. This method realistically reflects the effects of ground-motion and system design parameters, including the effects of a drifted oscillation center. The proposed method is therefore more appropriate than current existing simplified methods and can be applicable to isolation systems exhibiting a wider range of properties. A multi-level-hazard performance matrix has been adopted by different seismic provisions worldwide and will be incorporated into the new edition of the Canadian CSA-S6-14 Bridge Design code. However, the combined effect and optimal use of isolation and supplemental damping devices in bridges have not been fully exploited yet to achieve enhanced performance under different levels of seismic hazard. A novel Dual-Level Seismic

  17. Biaxial Behavior of Ultra-High Performance Concrete and Untreated UHPC Waffle Slab Bridge Deck Design and Testing

    NASA Astrophysics Data System (ADS)

    D'Alessandro, Kacie Caple

    Ultra-high performance concrete (UHPC) was evaluated as a potential material for future bridge deck designs. Material characterization tests took place to identify potential challenges in mixing, placing, and curing UHPC. Biaxial testing was performed to evaluate behavior of UHPC in combined tension and compression stress states. A UHPC bridge deck was designed to perform similarly to a conventional concrete bridge deck, and a single unit bridge deck section was tested to evaluate the design methods used for untreated UHPC. Material tests identified challenges with placing UHPC. A specified compressive strength was determined for structural design using untreated UHPC, which was identified as a cost-effective alternative to steam treated UHPC. UHPC was tested in biaxial tension-compression stress states. A biaxial test method was developed for UHPC to directly apply tension and compression. The influence of both curing method and fiber orientation were evaluated. The failure envelope developed for untreated UHPC with random fiber orientation was suggested as a conservative estimate for future analysis of UHPC. Digital image correlation was also evaluated as a means to estimate surface strains of UHPC, and recommendations are provided to improve consistency in future tests using DIC methods. A preliminary bridge deck design was completed for untreated UHPC and using established material models. Prestressing steel was used as primary reinforcement in the transverse direction. Preliminary testing was used to evaluate three different placement scenarios, and results showed that fiber settling was a potential placement problem resulting in reduced tensile strength. The UHPC bridge deck was redesigned to incorporate preliminary test results, and two single unit bridge deck sections were tested to evaluate the incorporated design methods for both upside down and right-side up placement techniques. Test results showed that the applied design methods would be conservative

  18. An amateur's contribution to the design of Telford's Menai Suspension Bridge: a commentary on Gilbert (1826) 'On the mathematical theory of suspension bridges'.

    PubMed

    Calladine, C R

    2015-04-13

    Davies Gilbert's work on the catenary is notable on two counts. First, it influenced Thomas Telford in formulating his final design for the Menai Strait suspension bridge (1826); and second, it established for the first time the form of the 'catenary of equal strength'. The classical catenary is a uniform flexible chain or cable hanging freely under gravity between supports. The 'catenary of equal strength' is the form of a cable whose cross-sectional area is made proportional to the tension at each point, so that the tensile stress is uniform throughout. In this paper I provide a sketch of the lives and achievements of Gilbert and Telford, and of their interaction over the Menai Bridge. There follows a commentary on Gilbert's 1826 paper, and on his two related publications; and a brief sketch of the earlier history of the catenary. I then describe the development of the suspension bridge up to the present time. Finally, I discuss relations between mathematical analysts and practical engineers. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society. PMID:25750153

  19. Chiral linker-bridged bis-N-heterocyclic carbenes: design, synthesis, palladium complexes, and catalytic properties.

    PubMed

    Zhang, Dao; He, Yu; Tang, Junkai

    2016-08-01

    A series of chiral bis(benzimidazolium) salts 10-19 with (1R,2R)-cyclohexene, (1R,2R)-diphenylethylene and (aR)-binaphthylene linkers have been designed and synthesized in 30-94% yield. Ten chiral bis(NHC) palladium complexes 20-28 have been synthesized and characterized by NMR, HRMS, elemental analysis and further confirmed by X-ray single crystal analysis. These bis(NHC)-Pd complexes showed obviously different catalytic properties in the asymmetric Suzuki-Miyaura coupling reactions. The (1R,2R)-cyclohexene-bridged bis(NHC)-Pd complex, (R,R)-23, achieved the highest yield of 90%, while complex (aR)-28, with a binaphthylene linker, showed the best enantioselectivity of 60 ee%. The structural analysis of these complexes suggested that such difference of catalytic performance has a close relationship with their coordination surroundings around metal centres. PMID:27230553

  20. Computational Protein Engineering: Bridging the Gap between Rational Design and Laboratory Evolution

    PubMed Central

    Barrozo, Alexandre; Borstnar, Rok; Marloie, Gaël; Kamerlin, Shina Caroline Lynn

    2012-01-01

    Enzymes are tremendously proficient catalysts, which can be used as extracellular catalysts for a whole host of processes, from chemical synthesis to the generation of novel biofuels. For them to be more amenable to the needs of biotechnology, however, it is often necessary to be able to manipulate their physico-chemical properties in an efficient and streamlined manner, and, ideally, to be able to train them to catalyze completely new reactions. Recent years have seen an explosion of interest in different approaches to achieve this, both in the laboratory, and in silico. There remains, however, a gap between current approaches to computational enzyme design, which have primarily focused on the early stages of the design process, and laboratory evolution, which is an extremely powerful tool for enzyme redesign, but will always be limited by the vastness of sequence space combined with the low frequency for desirable mutations. This review discusses different approaches towards computational enzyme design and demonstrates how combining newly developed screening approaches that can rapidly predict potential mutation “hotspots” with approaches that can quantitatively and reliably dissect the catalytic step can bridge the gap that currently exists between computational enzyme design and laboratory evolution studies. PMID:23202907

  1. A BASIC STUDY OF EVALUATION STRUCTURE TO VISUAL DESIGN OF NEO-FUNCTIONALISM BRIDGES

    NASA Astrophysics Data System (ADS)

    Matsui, Teppei; Sasaki, Yoh

    This research's final goal is to clarify how people focus on the external appearance of neo-functionalism bridges which are characterized by their distinguishing morphological features, and also determine whether people evaluate these bridges and how they do it. As a first step, the research focuses on the Through-type Arch Bridge and attempts to make clear the evaluation structure by means of an experimental psychology approach. Upon this, the dynamic image will be defined by the vitality flow and motion impression that characterize this kind of bridge. The sensibility evaluation experiment is carried out by using CG that reflects the changes of related feature shapes. Thus, the relationship between the assortments of the bridge's morphological characteristic and its impression are analyzed by using Rough Set Theory. As a result, it was possible to find out a variety of evaluation trends related to the intellectual background of the bridge observer and also establish the distinct characteristics of various evaluation trends.

  2. Topological design of all-ceramic dental bridges for enhancing fracture resistance.

    PubMed

    Zhang, Zhongpu; Chen, Junning; Li, Eric; Li, Wei; Swain, Michael; Li, Qing

    2016-06-01

    Layered all-ceramic systems have been increasingly adopted in major dental prostheses. However, ceramics are inherently brittle, and they often subject to premature failure under high occlusion forces especially in the posterior region. This study aimed to develop mechanically sound novel topological designs for all-ceramic dental bridges by minimizing the fracture incidence under given loading conditions. A bi-directional evolutionary structural optimization (BESO) technique is implemented within the extended finite element method (XFEM) framework. Extended finite element method allows modeling crack initiation and propagation inside all-ceramic restoration systems. Following this, BESO searches the optimum distribution of two different ceramic materials, namely porcelain and zirconia, for minimizing fracture incidence. A performance index, as per a ratio of peak tensile stress to material strength, is used as a design objective. In this study, the novel XFEM based BESO topology optimization significantly improved structural strength by minimizing performance index for suppressing fracture incidence in the structures. As expected, the fracture resistance and factor of safety of fixed partial dentures structure increased upon redistributing zirconia and porcelain in the optimal topological configuration. Dental CAD/CAM systems and the emerging 3D printing technology were commercially available to facilitate implementation of such a computational design, exhibiting considerable potential for clinical application in the future. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26444905

  3. Design and analysis of the tracker bridge for the Hobby-Eberly Telescope wide-field upgrade

    NASA Astrophysics Data System (ADS)

    Worthington, Michael S.; Mollison, Nicholas T.; Soukup, Ian M.; Zierer, Joseph J.; Good, John M.; Nichols, Steven P.

    2010-07-01

    A large structural weldment has been designed to serve as the new star tracker bridge for the Wide Field Upgrade to the Hobby-Eberly Telescope at McDonald Observatory in support of the Hobby-Eberly Telescope Dark Energy Experiment‡. The modeling approach, analysis techniques and design details will be of interest to designers of large structures where stiffness is the primary design driver. The design includes detailed structural analysis using finite element models to maximize natural frequency response and limit deflections and light obscuration. Considerable fabrication challenges are overcome to allow integration of precision hardware required for positioning the corrector optics to a precision of less than 5 microns along the 4-meter travel range. Detailed descriptions of the bridge geometry, analysis results and challenging fabrication issues are discussed.

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

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

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

  5. Using a Bridging Representation and Social Interactions to Foster Conceptual Change: Designing and Evaluating an Instructional Sequence for Newton's Third Law

    ERIC Educational Resources Information Center

    Savinainen, Antti; Scott, Philip; Viiri, Jouni

    2005-01-01

    This paper offers an account of, and findings from, an approach to designing and evaluating an instructional sequence set in the context of Newton's third law. The design of the sequence draws upon conceptual change theory and the concept of the "bridging analog" is extended to introduce the notion of a "bridging representation" Attention is also…

  6. Design and fabrication of indium phosphide air-bridge waveguides with MEMS functionality

    NASA Astrophysics Data System (ADS)

    Ng, Wing H.; Podoliak, Nina; Horak, Peter; Wu, Jiang; Liu, Huiyun; Stewart, William J.; Kenyon, Anthony J.

    2015-05-01

    We present the design and fabrication of a dual air-bridge waveguide structure integrated with MEMS functionality. The structure is designed to function as a tunable optical buffer for telecommunication application. The optical buffer structure is based on two parallel waveguides made of high refractive index material with subwavelength dimensions. They are suspended in air, and are separated by a sub-micron air gap. Due to the fact that the size of the waveguides is much smaller than the wavelength of light that propagates in the structure, a significant fraction of the optical mode is in the air gap between the waveguides. By changing the size of the air gap using MEMS techniques, we can vary this fraction and hence the effective refractive index of the waveguide structure, thus generating tunable optical delay. The optical buffer structure was grown on an InP substrate by molecular beam epitaxy, and the device layer was made of InGaP. An InGaAs layer was sandwiched between the device layer and the substrate to serve as a sacrificial layer. The sub-micron waveguides, their supports in the form of side pillars with tapered shapes in order to minimize optical losses, and the MEMS structures were patterned using electron beam lithography and plasma etching. Electrodes were integrated into the structure to provide electrostatic actuation. After the sample patterning, the waveguide structure was released using HF etch. Our simulations predict that by varying the waveguide separation from 50 nm to 500 nm, we could achieve a change in propagation delay by a factor of two.

  7. Issues in Designing Tutors for Games of Incomplete Information: a Bridge Case Study

    NASA Astrophysics Data System (ADS)

    Kemp, Ray; McKenzie, Ben; Kemp, Elizabeth

    There are a number of commercial packages for playing the game of bridge, and even more papers on possible techniques for improving the quality of such systems. We examine some of the AI techniques that have proved successful for implementing bridge playing systems and discuss how they might be adapted for teaching the game. We pay particular attention to the issue of incomplete information and include some of our own research into the subject.

  8. Design and parametric study on energy harvesting from bridge vibration using tuned dual-mass damper systems

    NASA Astrophysics Data System (ADS)

    Takeya, Kouichi; Sasaki, Eiichi; Kobayashi, Yusuke

    2016-01-01

    A bridge vibration energy harvester has been proposed in this paper using a tuned dual-mass damper system, named hereafter Tuned Mass Generator (TMG). A linear electromagnetic transducer has been applied to harvest and make use of the unused reserve of energy the aforementioned damper system absorbs. The benefits of using dual-mass systems over single-mass systems for power generation have been clarified according to the theory of vibrations. TMG parameters have been determined considering multi-domain parameters, and TMG has been tuned using a newly proposed parameter design method. Theoretical analysis results have shown that for effective energy harvesting, it is essential that TMG has robustness against uncertainties in bridge vibrations and tuning errors, and the proposed parameter design method for TMG has demonstrated this feature.

  9. Experimental design for the evaluation of high-T(sub c) superconductive thermal bridges in a sensor satellite

    NASA Technical Reports Server (NTRS)

    Scott, Elaine P.; Lee, Kasey M.

    1994-01-01

    Infrared sensor satellites, which consist of cryogenic infrared sensor detectors, electrical instrumentation, and data acquisition systems, are used to monitor the conditions of the earth's upper atmosphere in order to evaluate its present and future changes. Currently, the electrical connections (instrumentation), which act as thermal bridges between the cryogenic infrared sensor and the significantly warmer data acquisition unit of the sensor satellite system, constitute a significant portion of the heat load on the cryogen. As a part of extending the mission life of the sensor satellite system, the researchers at the National Aeronautics and Space Administration's Langley Research Center (NASA-LaRC) are evaluating the effectiveness of replacing the currently used manganin wires with high-temperature superconductive (HTS) materials as the electrical connections (thermal bridges). In conjunction with the study being conducted at NASA-LaRC, the proposed research is to design a space experiment to determine the thermal savings on a cryogenic subsystem when manganin leads are replaced by HTS leads printed onto a substrate with a low thermal conductivity, and to determine the thermal conductivities of HTS materials. The experiment is designed to compare manganin wires with two different types of superconductors on substrates by determining the heat loss by the thermal bridges and providing temperature measurements for the estimation of thermal conductivity. A conductive mathematical model has been developed and used as a key tool in the design process and subsequent analysis.

  10. Environmentally Friendly Solution to Ground Hazards in Design of Bridges in Earthquake Prone Areas Using Timber Piles

    NASA Astrophysics Data System (ADS)

    Sadeghi, H.

    2015-12-01

    Bridges are major elements of infrastructure in all societies. Their safety and continued serviceability guaranties the transportation and emergency access in urban and rural areas. However, these important structures are subject to earthquake induced damages in structure and foundations. The basic approach to the proper support of foundations are a) distribution of imposed loads to foundation in a way they can resist those loads without excessive settlement and failure; b) modification of foundation ground with various available methods; and c) combination of "a" and "b". The engineers has to face the task of designing the foundations meeting all safely and serviceability criteria but sometimes when there are numerous environmental and financial constrains, the use of some traditional methods become inevitable. This paper explains the application of timber piles to improve ground resistance to liquefaction and to secure the abutments of short to medium length bridges in an earthquake/liquefaction prone area in Bohol Island, Philippines. The limitations of using the common ground improvement methods (i.e., injection, dynamic compaction) because of either environmental or financial concerns along with the abundance of timber in the area made the engineers to use a network of timber piles behind the backwalls of the bridge abutments. The suggested timber pile network is simulated by numerical methods and its safety is examined. The results show that the compaction caused by driving of the piles and bearing capacity provided by timbers reduce the settlement and lateral movements due to service and earthquake induced loads.

  11. Theoretical design and screening of alkyne bridged triphenyl zinc porphyrins as sensitizer candidates for dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Xianxi; Chen, Qianqian; Sun, Huafei; Pan, Tingting; Hu, Guiqi; Ma, Ruimin; Dou, Jianmin; Li, Dacheng; Pan, Xu

    2014-01-01

    Alkyne bridged porphyrins have been proved very promising sensitizers for dye-sensitized solar cells (DSSCs) with the highest photo-to-electric conversion efficiencies of 11.9% solely and 12.3% co-sensitized with other sensitizers achieved. Developing better porphyrin sensitizers with wider electronic absorption spectra to further improve the efficiencies of corresponding solar cells is still of great significance for the application of DSSCs. A series of triphenyl zinc porphyrins (ZnTriPP) differing in the nature of a pendant acceptor group and the conjugated bridge between the porphyrin nucleus and the acceptor unit were modeled and their electronic and spectral properties calculated using density functional theory. As compared with each other and the experimental results of the compounds used in DSSCs previously, the molecules with a relatively longer conjugative linker and a strong electron-withdrawing group such as cyanide adjacent to the carboxyl acid group seem to provide wider electronic absorption spectra and higher photo-to-electric conversion efficiencies. The dye candidates ZnTriPPE, ZnTriPPM, ZnTriPPQ, ZnTriPPR and ZnTriPPS designed in the current work were found promising to provide comparable photo-to-electric conversion efficiencies to the record 11.9% of the alkyne bridged porphyrin sensitizer YD2-o-C8 reported previously.

  12. Design and optimization of micro-semiconductor bridge used for solid propellant microthrusters array

    NASA Astrophysics Data System (ADS)

    Ru, Chengbo; Dai, Ji; Xu, Jianbing; Ye, Yinghua; Zhu, Peng; Shen, Ruiqi

    2016-06-01

    Igniter is the basic component of MEMS-based solid propellant microthrusters (SPM) array, which should response fast with low dissipated energy. To satisfy the requirements, micro-semiconductor bridge (MSCB) with dual V-angles contributing to the reduction of dissipated energy is introduced into the array. The electrical explosion characteristics of MSCB investigated under constant voltage, in the considerations of the limit of power supply in the micro/nanosatellite, are similar to those under capacitive discharge. The bridge was completely vaporized and burst into the hot plasma under high-level voltage. While under low-level voltage, the bridge was partly vaporized without detected plasma. The 3#SCB (90° V-angle) with the smallest power density resulting in the lowest applied voltage (12.0 V) and the 2#SCB with the smallest narrow width (Wmin) leading to the lowest average power (11.3 W) were chosen to the further optimization. The ignition tests were implemented to examine the ignition reliability of the contractible igniters, which were optimized to satisfy the voltage limitation with sufficient ignition capacity. The results show that the effective SCB with lowest dissipated power is the 3#-3SCB, which function within 100 μ under 7.0 V, and the average power below 5.0 W.

  13. Bridge permeameter

    DOEpatents

    Graf, Darin C.; Warpinski, Norman R.

    1996-01-01

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

  14. Bridging the Gap between Experts in Designing Multimedia-Based Instructional Media for Learning

    ERIC Educational Resources Information Center

    Razak, Rafiza Abdul

    2013-01-01

    The research identified and explored the cognitive knowledge among the instructional multimedia design and development experts comprising of multimedia designer, graphic designer, subject-matter expert and instructional designer. A critical need exists for a solid understanding of the factors that influence team decision making and performance in…

  15. Can kinomics and proteomics bridge the gap between pediatric cancers and newly designed kinase inhibitors?

    PubMed

    van der Sligte, Naomi E; Kampen, Kim R; de Bont, Eveline S J M

    2015-10-01

    The introduction of kinase inhibitors in cancer medicine has transformed chronic myeloid leukemia from a fatal disease into a leukemia subtype with a favorable prognosis by interfering with the constitutively active kinase BCR-ABL. This success story has resulted in the development of multiple kinase inhibitors. We are currently facing significant limitations in implementing these kinase inhibitors into the clinic for the treatment of pediatric malignancies. As many hallmarks of cancer are known to be regulated by intracellular protein signaling networks, we suggest focusing on these networks to improve the implementation of kinase inhibitors. This viewpoint will provide a short overview of currently used strategies for the implementation of kinase inhibitors as well as reasons why kinase inhibitors have unfortunately not yet been widely used for the treatment of pediatric cancers. We argue that by using a future personalized medicine strategy combining kinomics, proteomics, and drug screen approaches, the gap between pediatric cancers and the use of kinase inhibitors may be bridged. PMID:26321002

  16. Enhancing the thermostability of a cold-active lipase from Penicillium cyclopium by in silico design of a disulfide bridge.

    PubMed

    Tan, Zhongbiao; Li, Jianfang; Wu, Minchen; Wang, Junqing

    2014-08-01

    Cysteine mutants of a cold-active lipase (PcLipI) from Penicillium cyclopium were designed by the software Disulfide by Design Ver. 1.20 in an effort to improve enzyme thermostability by addition of a disulfide bridge. Those mutants predicted by molecular dynamics simulation to have better thermostability than the wild type were first expressed in Escherichia coli BL21(DE3) and then, for further investigation, in Pichia pastoris GS115. By replacing Val248 and Thr251 with cysteines to create a disulfide bridge, the recombinant lipases reE-PcLipV248C-T251C (expressed in E. coli) and reP-PcLipV248C-T251C (expressed in P. pastoris) were obtained. Both had enhanced thermostability with half-lives at 35 °C about 4.5- and 12.8-fold longer than that of the parent PcLipI expressed in E. coli and P. pastoris, respectively. The temperature optima of reE-PcLipV248C-T251C and reP-PcLipV248C-T251C were 35 and 30 °C, which were each 5 °C higher than those of the parent PcLipI expressed in E. coli and P. pastoris. The K ms of reE-PcLipV248C-T251C and reP-PcLipV248C-T251C toward tributyrin were 53.2 and 39.5 mM, while their V maxs were 1,460 and 3,800 U/mg, respectively. PcLipV248C-T251C had better thermostability and catalytic efficiency than the other mutants and the parent PcLipI. PMID:24867629

  17. Design and testing of a low-power wireless sensor network for structural health monitoring of bridges

    NASA Astrophysics Data System (ADS)

    Harms, T.; Banks, B.; Sedigh Sarvestani, S.; Bastianini, F.

    2009-03-01

    This paper describes the design and testing of a wireless sensor network based on the SmartBrick, a low-power SHM device developed by the authors. The SmartBrick serves as the base station for the network, which utilizes additional sensor nodes to periodically evaluate the condition of the structure. Each node measures vibration, tilt, humidity, and strain, and is designed for easy interfacing of virtually any other analog or digital sensor. The sensor nodes use Zigbee to transmit their data to the base station, which in turn uses the GSM cellular phone network to provide long-range communication and support for remote control. The system has been designed from the outset to minimize power consumption, and is projected to operate autonomously for up to four years without any on-site maintenance, due largely to the minimal power consumption and rugged design. Remote calibration over the GSM network further increases the autonomy of the system. Most importantly, it can perform all requisite actions with no cables for power or communication. The focus of this paper is the addition of short-range wireless communication over Zigbee. This allows a network of several devices to be used to monitor larger structures, such as multi-span bridges. Results of laboratory testing are included and discussed in detail, demonstrating the unique capabilities of the proposed SHM system.

  18. The active-bridge oscillator

    SciTech Connect

    Wessendorf, K.O.

    1998-07-01

    This paper describes the Active-Bridge Oscillator (ABO), a new concept in high-stability oscillator design. The ABO is ab ridge-type oscillator design that is easly to design and overcomes many of the operational and design difficulties associated with standard bridge oscillator designs. The ABO will oscillate with a very stable output amplitude over a wide range of operating conditions without the use of an automatic-level-control (ALC). A standard bridge oscillator design requires an ALC to maintain the desired amplitude of oscillation. for this and other reasons, bridge oscilaltors are not used in mainstream designs. Bridge oscillators are generally relegated to relatively low-volume, high-performance applications. The Colpitts and Pierce designs are the most popular oscillators but are typically less stable than a bridge-type oscillator.

  19. User Studies and Systems Design: Bridging the Gap (SIGs USE, HCI).

    ERIC Educational Resources Information Center

    Robins, David

    2000-01-01

    Presents an abstract for a planned session on the need to coordinate user studies and information retrieval system design research. Topics include human-based research and system-based research; children's information use; usability and cartographic information systems; and ethnomethodology and system design. Panelists included: Nick Belkin, Dania…

  20. Bridging the Gap between Designers and Consumers: The Role of Effective and Accurate Personas

    ERIC Educational Resources Information Center

    Miaskiewicz, Tomasz

    2010-01-01

    Firms now routinely collect information about the needs of their customers, but this information is not sufficiently considered during product design decisions. This research examines the relationship between designers and consumers to build an understanding of how the consumer should be represented to increase the consumer focus during the…

  1. Uptake and Use of Technology: Bridging Design for Teaching and Learning

    ERIC Educational Resources Information Center

    Hauge, Trond Eiliv

    2014-01-01

    This paper demonstrates the need for taking a design perspective on teaching and learning in the study of the uptake and use of information and communication technologies (ICT) in education. It argues for the identification and scrutiny of designs for teaching and learning at the institutional level to overcome the contradictions that often arise…

  2. Bridge permeameter

    DOEpatents

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

    1996-08-13

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

  3. Bridging the Problem-Solver Communication Gap: Toward an Art of Professional Case Design.

    ERIC Educational Resources Information Center

    Johnson, Robert; Simpson, Mark

    1990-01-01

    Evaluates well-designed cases involving students in situations which simulate those outside the classroom environment. Offers additional features based on problem solving and rhetorical theory to help make cases more adaptable to the field of professional communications. Describes examples of two types of cases which put the theory into practice.…

  4. Bridging the gap: a roadmap to breaking the biological design barrier.

    PubMed

    Beal, Jacob

    2014-01-01

    This paper presents an analysis of an emerging bottleneck in organism engineering, and paths by which it may be overcome. Recent years have seen the development of a profusion of synthetic biology tools, largely falling into two categories: high-level "design" tools aimed at mapping from organism specifications to nucleic acid sequences implementing those specifications, and low-level "build and test" tools aimed at faster, cheaper, and more reliable fabrication of those sequences and assays of their behavior in engineered biological organisms. Between the two families, however, there is a major gap: we still largely lack the predictive models and component characterization data required to effectively determine which of the many possible candidate sequences considered in the design phase are the most likely to produce useful results when built and tested. As low-level tools continue to mature, the bottleneck in biological systems engineering is shifting to be dominated by design, making this gap a critical barrier to progress. Considering how to address this gap, we find that widespread adoption of readily available analytic and assay methods is likely to lead to rapid improvement in available predictive models and component characterization models, as evidenced by a number of recent results. Such an enabling development is, in turn, likely to allow high-level tools to break the design barrier and support rapid development of transformative biological applications. PMID:25654077

  5. Cybersecurity Protection: Design Science Research toward an Intercloud Transparent Bridge Architecture (ICTOBRA)

    ERIC Educational Resources Information Center

    Wilson, Joe M.

    2013-01-01

    This dissertation uses design science research and engineering to develop a cloud-based simulator for modeling next-generation cybersecurity protection frameworks in the United States. The claim is made that an agile and neutral framework extending throughout the cyber-threat plane is needed for critical infrastructure protection (CIP). This…

  6. Effects of Thinking Style on Design Strategies: Using Bridge Construction Simulation Programs

    ERIC Educational Resources Information Center

    Sun, Chuen-Tsai; Wang, Dai-Yi; Chang, Yu-Yeh

    2013-01-01

    Computer simulation users can freely control operational factors and simulation results, repeat processes, make changes, and learn from simulation environment feedback. The focus of this paper is on simulation-based design tools and their effects on student learning processes in a group of 101 Taiwanese senior high school students. Participants…

  7. Structure-Based Design of a Novel SMYD3 Inhibitor that Bridges the SAM-and MEKK2-Binding Pockets.

    PubMed

    Van Aller, Glenn S; Graves, Alan P; Elkins, Patricia A; Bonnette, William G; McDevitt, Patrick J; Zappacosta, Francesca; Annan, Roland S; Dean, Tony W; Su, Dai-Shi; Carpenter, Christopher L; Mohammad, Helai P; Kruger, Ryan G

    2016-05-01

    SMYD3 is a lysine methyltransferase overexpressed in colorectal, breast, prostate, and hepatocellular tumors, and has been implicated as an oncogene in human malignancies. Methylation of MEKK2 by SMYD3 is important for regulation of the MEK/ERK pathway, suggesting the possibility of selectively targeting SMYD3 in RAS-driven cancers. Structural and kinetic characterization of SMYD3 was undertaken leading to a co-crystal structure of SMYD3 with a MEKK2-peptide substrate bound, and the observation that SMYD3 follows a partially processive mechanism. These insights allowed for the design of GSK2807, a potent and selective, SAM-competitive inhibitor of SMYD3 (Ki = 14 nM). A high-resolution crystal structure reveals that GSK2807 bridges the gap between the SAM-binding pocket and the substrate lysine tunnel of SMYD3. Taken together, our data demonstrate that small-molecule inhibitors of SMYD3 can be designed to prevent methylation of MEKK2 and these could have potential use as anticancer therapeutics. PMID:27066749

  8. Technology Transfer--Bridging Space and Society. The Students of the Technology Transfer Design Project Team (ISU Summer Session 1997).

    PubMed

    1997-01-01

    Strategies, policies and methods by which technologies can he cross-fertilized between the space and non-space sectors were examined by students of the design project "Technology Transfer--Bridging Space and Society". This project was undertaken by students attending the 1997 10th Anniversary Summer Session Program of the International Space University. General issues relating to transfer of technology were discussed including definitions and mechanisms (push, pull, interactive and pro-active). As well as looking at case studies and the impact of national policies on space agencies, the design project also sought to look at technology transfer on a country-by-country basis, selecting various countries for scrutiny and reporting on their technology transfer status. The project report shows how transfer of technology varies between nations and when analyzed with the case studies identifies the general strategies, policies and methods in use and how they can he improved. Finally, the report seeks to recommend certain issues to governments, space agencies and industrial organizations to facilitate the transfer of technology. These include the development of a generic metrics system and the implementation of better appropriate procedures and mechanisms for a positive diffusion process between space and non-space sectors. PMID:11541148

  9. Bridging the Gap: A Roadmap to Breaking the Biological Design Barrier

    PubMed Central

    Beal, Jacob

    2015-01-01

    This paper presents an analysis of an emerging bottleneck in organism engineering, and paths by which it may be overcome. Recent years have seen the development of a profusion of synthetic biology tools, largely falling into two categories: high-level “design” tools aimed at mapping from organism specifications to nucleic acid sequences implementing those specifications, and low-level “build and test” tools aimed at faster, cheaper, and more reliable fabrication of those sequences and assays of their behavior in engineered biological organisms. Between the two families, however, there is a major gap: we still largely lack the predictive models and component characterization data required to effectively determine which of the many possible candidate sequences considered in the design phase are the most likely to produce useful results when built and tested. As low-level tools continue to mature, the bottleneck in biological systems engineering is shifting to be dominated by design, making this gap a critical barrier to progress. Considering how to address this gap, we find that widespread adoption of readily available analytic and assay methods is likely to lead to rapid improvement in available predictive models and component characterization models, as evidenced by a number of recent results. Such an enabling development is, in turn, likely to allow high-level tools to break the design barrier and support rapid development of transformative biological applications. PMID:25654077

  10. HomoSAR: bridging comparative protein modeling with quantitative structural activity relationship to design new peptides.

    PubMed

    Borkar, Mahesh R; Pissurlenkar, Raghuvir R S; Coutinho, Evans C

    2013-11-15

    Peptides play significant roles in the biological world. To optimize activity for a specific therapeutic target, peptide library synthesis is inevitable; which is a time consuming and expensive. Computational approaches provide a promising way to simply elucidate the structural basis in the design of new peptides. Earlier, we proposed a novel methodology termed HomoSAR to gain insight into the structure activity relationships underlying peptides. Based on an integrated approach, HomoSAR uses the principles of homology modeling in conjunction with the quantitative structural activity relationship formalism to predict and design new peptide sequences with the optimum activity. In the present study, we establish that the HomoSAR methodology can be universally applied to all classes of peptides irrespective of sequence length by studying HomoSAR on three peptide datasets viz., angiotensin-converting enzyme inhibitory peptides, CAMEL-s antibiotic peptides, and hAmphiphysin-1 SH3 domain binding peptides, using a set of descriptors related to the hydrophobic, steric, and electronic properties of the 20 natural amino acids. Models generated for all three datasets have statistically significant correlation coefficients (r(2)) and predictive r2 (r(pred)2) and cross validated coefficient ( q(LOO)2). The daintiness of this technique lies in its simplicity and ability to extract all the information contained in the peptides to elucidate the underlying structure activity relationships. The difficulties of correlating both sequence diversity and variation in length of the peptides with their biological activity can be addressed. The study has been able to identify the preferred or detrimental nature of amino acids at specific positions in the peptide sequences. PMID:24105965

  11. Bridging Differences in Outcomes of Pharmacoepidemiological Studies: Design and First Results of the PROTECT Project

    PubMed Central

    Abbing-Karahagopian, Victoria; Kurz, Xavier; de Vries, Frank; van Staa, Tjeerd P.; Alvarez, Yolanda; Hesse, Ulrik; Hasford, Joerg; Liset van, Dijk; Francisco J. de, Abajo; Weil, John G.; Lamiae Grimaldi, -Bensouda; Egberts, Antoine C.G.; Robert F., Reynolds; Olaf H., Klungel

    2014-01-01

    Background: Observational pharmacoepidemiological (PE) studies on drug safety have produced discrepant results that may be due to differences in design, conduct and analysis. Purpose: The pharmacoepidemiology work-package (WP2) of the Pharmacoepidemiological Research on Outcomes of Therapeutics by a European ConsorTium (PROTECT) project aims at developing, testing and disseminating methodological standards for design, conduct and analysis of pharmacoepidemiological studies applicable to different safety issues using different databases across European countries. This article describes the selection of the safety issues and the description of the databases to be systematically studied. Methods: Based on two consensus meetings and a literature search, we selected five drug-adverse event (AE) pairs to be evaluated in different databases. This selection was done according to pre-defined criteria such as regulatory and public health impact, and the potential to investigate a broad range of methodological issues. Results: The selected drug-AE pairs are: 1) inhaled long-acting beta-2 agonists and acute myocardial infarction; 2) antimicrobials and acute liver injury; 3) antidepressants and/or benzodiazepines and hip fracture; 4) anticonvulsants and suicide/suicide attempts; and 5) calcium channel blockers and malignancies. Six European databases, that will be used to evaluate the drug-AE pairs retrospectively, are also described. Conclusion: The selected drug-AE pairs will be evaluated in PE studies using common protocols. Based on consistencies and discrepancies of these studies, a framework for guiding methodological choices will be developed. This will increase the usefulness and reliability of PE studies for benefit-risk assessment and decision-making. PMID:24218995

  12. Design, Synthesis, and Biological Evaluation of Novel Pyridine-Bridged Analogues of Combretastatin-A4 as Anticancer Agents

    PubMed Central

    2015-01-01

    A series of novel pyridine-bridged analogues of combretastatin-A4 (CA-4) were designed and synthesized. As expected, the 4-atom linker configuration retained little cytotoxicities in the compounds 2e, 3e, 3g, and 4i. Activities of the analogues with 3-atom linker varied widely depending on the phenyl ring substitutions, and the 3-atom linker containing nitrogen represents the more favorable linker structure. Among them, three analogues (4h, 4s, and 4t) potently inhibited cell survival and growth, arrested cell cycle, and blocked angiogenesis and vasculature formation in vivo in ways comparable to CA-4. The superposition of 4h and 4s in the colchicine-binding pocket of tubulin shows the binding posture of CA-4, 4h, and 4s are similar, as confirmed by the competitive binding assay where the ability of the ligands to replace tubulin-bound colchicine was measured. The binding data are consistent with the observed biological activities in antiproliferation and suppression of angiogenesis but are not predictive of their antitubulin polymerization activities. PMID:24669888

  13. Bridging the conservation design and delivery gap for wetland bird habitat maintenance and restoration in the Midwestern United States

    USGS Publications Warehouse

    Thogmartin, W.E.; Potter, B.; Soulliere, G.

    2011-01-01

    The U.S. Fish and Wildlife Service's adoption of Strategic Habitat Conservation is intended to increase the effectiveness and efficiency of conservation delivery by targeting effort in areas where biological benefits are greatest. Conservation funding has not often been allocated in accordance with explicit biological endpoints, and the gap between conservation design (the identification of conservation priority areas) and delivery needs to be bridged to better meet conservation goals for multiple species and landscapes. We introduce a regional prioritization scheme for North American Wetlands Conservation Act funding which explicitly addresses Midwest regional goals for wetland-dependent birds. We developed decision-support maps to guide conservation of breeding and non-breeding wetland bird habitat. This exercise suggested ~55% of the Midwest consists of potential wetland bird habitat, and areas suited for maintenance (protection) were distinguished from those most suited to restoration. Areas with greater maintenance focus were identified for central Minnesota, southeastern Wisconsin, the Upper Mississippi and Illinois rivers, and the shore of western Lake Erie and Saginaw Bay. The shores of Lakes Michigan and Superior accommodated fewer waterbird species overall, but were also important for wetland bird habitat maintenance. Abundant areas suited for wetland restoration occurred in agricultural regions of central Illinois, western Iowa, and northern Indiana and Ohio. Use of this prioritization scheme can increase effectiveness, efficiency, transparency, and credibility to land and water conservation efforts for wetland birds in the Midwestern United States.

  14. Ontology Design Patterns: Bridging the Gap Between Local Semantic Use Cases and Large-Scale, Long-Term Data Integration

    NASA Astrophysics Data System (ADS)

    Shepherd, Adam; Arko, Robert; Krisnadhi, Adila; Hitzler, Pascal; Janowicz, Krzysztof; Chandler, Cyndy; Narock, Tom; Cheatham, Michelle; Schildhauer, Mark; Jones, Matt; Raymond, Lisa; Mickle, Audrey; Finin, Tim; Fils, Doug; Carbotte, Suzanne; Lehnert, Kerstin

    2015-04-01

    Integrating datasets for new use cases is one of the common drivers for adopting semantic web technologies. Even though linked data principles enables this type of activity over time, the task of reconciling new ontological commitments for newer use cases can be daunting. This situation was faced by the Biological and Chemical Oceanography Data Management Office (BCO-DMO) as it sought to integrate its existing linked data with other data repositories to address newer scientific use cases as a partner in the GeoLink Project. To achieve a successful integration with other GeoLink partners, BCO-DMO's metadata would need to be described using the new ontologies developed by the GeoLink partners - a situation that could impact semantic inferencing, pre-existing software and external users of BCO-DMO's linked data. This presentation describes the process of how GeoLink is bridging the gap between local, pre-existing ontologies to achieve scientific metadata integration for all its partners through the use of ontology design patterns. GeoLink, an NSF EarthCube Building Block, brings together experts from the geosciences, computer science, and library science in an effort to improve discovery and reuse of data and knowledge. Its participating repositories include content from field expeditions, laboratory analyses, journal publications, conference presentations, theses/reports, and funding awards that span scientific studies from marine geology to marine ecology and biogeochemistry to paleoclimatology. GeoLink's outcomes include a set of reusable ontology design patterns (ODPs) that describe core geoscience concepts, a network of Linked Data published by participating repositories using those ODPs, and tools to facilitate discovery of related content in multiple repositories.

  15. The Building Bridges Project: Involving Older Adults in the Design of a Communication Technology to Support Peer-to-Peer Social Engagement

    NASA Astrophysics Data System (ADS)

    Wherton, Joseph; Prendergast, David

    There are a variety of factors that can lead to social isolation and loneliness in old age, including decline in physical and mental health, as well as change to social environment. The Building Bridges project explores how communication technology can help older adults remain socially connected. This paper will first provide an overview of a prototype communication system designed to support peer-to-peer group interaction. A description of the user-centered design process will be provided to demonstrate the importance of involving older adults at the earliest stages. The implications for designing new technology for older adults are discussed.

  16. Safer Bridges

    NASA Technical Reports Server (NTRS)

    1977-01-01

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

  17. Development of Inspection Robots for Bridge Cables

    PubMed Central

    Kim, Se-Hoon; Lee, Jong-Jae

    2013-01-01

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

  18. Structural characterization of metallopeptides designed as scaffolds for the stabilization of nickel(II)-Fe(4)S(4) bridged assemblies by X-ray absorption spectroscopy.

    PubMed

    Musgrave, Kristin B; Laplaza, Catalina E; Holm, R H; Hedman, Britt; Hodgson, Keith O

    2002-03-27

    In earlier work, de novo designed peptides with a helix-loop-helix motif and 63 residues have been synthesized as potential scaffolds for stabilization of the [Ni(II)-X-Fe(4)S(4)] bridged assembly that is the spectroscopically deduced structure of the A-Cluster in clostridial carbon monoxide dehydrogenase. The 63mers contain a consensus tricysteinyl ferredoxin domain in the loop for binding an Fe(4)S(4) cluster and Cys and His residues proximate to the loop for binding Ni(II), with one Cys residue designed as the bridge X. The metallopeptides HC(4)H(2)-[Fe(4)S(4)]-Ni and HC(5)H-[Fe(4)S(4)]-M, containing three His and one Cys residue for Ni(II) coordination and two His and two Cys residues for binding M = Ni(II) and Co(II), have been examined by Fe-, Ni-, and Co-K edge spectroscopy and EXAFS. All peptides bind an [Fe(4)S(4)](2+) cubane-type cluster. Interpretation of the Ni and Co data is complicated by the presence of a minority population of six-coordinate species with low Z ligands, designated for simplicity as [M(OH(2))(6)](2+). Best fits of the data were obtained with ca. 20% [M(OH(2))(6)](2+) and ca. 80% M(II) with mixed N/S coordination. The collective XAS results for HC(4)H(2)-[Fe(4)S(4)]-Ni and HC(5)H-[Fe(4)S(4)]-M demonstrate the presence of an Fe(4)S(4) cluster and support the existence of the distorted square-planar coordination units [Ni(II)(S.Cys)(N.His)(3)] and [Ni(II)(S.Cys)(2)(N.His)(2)] in the HC(4)H(2) and HC(5)H metallopeptides, respectively. In the HC(5)H metallopeptide, tetrahedral [Co(II)(S.Cys)(2)(N.His)(2)] is present. We conclude that the designed scaffolded binding sites, including Ni-(mu(2)-S.Cys)-Fe bridges, have been achieved. This is the first XAS study of a de novo designed metallopeptide intended to stabilize a bridged biological assembly, and one of a few XAS analyses of metal derivatives of designed peptides. The scaffolding concept should be extendable to other bridged metal assemblies. PMID:11902899

  19. Building a Straw Bridge

    ERIC Educational Resources Information Center

    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,…

  20. Propylene cross-bridged macrocyclic bifunctional chelator: a new design for facile bioconjugation and robust (64)Cu complex stability.

    PubMed

    Pandya, Darpan N; Bhatt, Nikunj; An, Gwang Il; Ha, Yeong Su; Soni, Nisarg; Lee, Hochun; Lee, Yong Jin; Kim, Jung Young; Lee, Woonghee; Ahn, Heesu; Yoo, Jeongsoo

    2014-09-11

    The first macrocyclic bifunctional chelator incorporating propylene cross-bridge was efficiently synthesized from cyclam in seven steps. After the introduction of an extra functional group for facile conjugation onto the propylene cross-bridge, the two carboxylic acid pendants could contribute to strong coordination of Cu(II) ions, leading to a robust Cu complex. The cyclic RGD peptide conjugate of PCB-TE2A-NCS was prepared and successfully radiolabeled with (64)Cu ion. The radiolabeled peptide conjugate was evaluated in vivo through a biodistribution study and animal PET imaging to demonstrate high tumor uptake with low background. PMID:25137619

  1. 49 CFR 237.107 - Conduct of bridge inspections.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

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

  2. 49 CFR 237.107 - Conduct of bridge inspections.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

  3. 49 CFR 237.107 - Conduct of bridge inspections.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

  4. Myocardial Bridge

    MedlinePlus

    ... artery. See also on this site: Ask a Texas Heart Institute Doctor: Search "myocardial bridge" Updated August ... comments. Terms of Use and Privacy Policy © Copyright Texas Heart Institute All rights reserved.

  5. An amateur's contribution to the design of Telford's Menai Suspension Bridge: a commentary on Gilbert (1826) ‘On the mathematical theory of suspension bridges’

    PubMed Central

    Calladine, C. R.

    2015-01-01

    Davies Gilbert's work on the catenary is notable on two counts. First, it influenced Thomas Telford in formulating his final design for the Menai Strait suspension bridge (1826); and second, it established for the first time the form of the ‘catenary of equal strength’. The classical catenary is a uniform flexible chain or cable hanging freely under gravity between supports. The ‘catenary of equal strength’ is the form of a cable whose cross-sectional area is made proportional to the tension at each point, so that the tensile stress is uniform throughout. In this paper I provide a sketch of the lives and achievements of Gilbert and Telford, and of their interaction over the Menai Bridge. There follows a commentary on Gilbert's 1826 paper, and on his two related publications; and a brief sketch of the earlier history of the catenary. I then describe the development of the suspension bridge up to the present time. Finally, I discuss relations between mathematical analysts and practical engineers. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society. PMID:25750153

  6. Mathematics in Use: Suspension Bridges.

    ERIC Educational Resources Information Center

    Ginther, John L.

    1992-01-01

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

  7. A designed 5-fluorouracil-based bridged silsesquioxane as an autonomous acid-triggered drug-delivery system.

    PubMed

    Giret, Simon; Théron, Christophe; Gallud, Audrey; Maynadier, Marie; Gary-Bobo, Magali; Garcia, Marcel; Wong Chi Man, Michel; Carcel, Carole

    2013-09-16

    Two new prodrugs, bearing two and three 5-fluorouracil (5-FU) units, respectively, have been synthesized and were shown to efficiently treat human breast cancer cells. In addition to 5-FU, they were intended to form complexes through H-bonds to an organo-bridged silane prior to hydrolysis-condensation through sol-gel processes to construct acid-responsive bridged silsesquioxanes (BS). Whereas 5-FU itself and the prodrug bearing two 5-FU units completely leached out from the corresponding materials, the prodrug bearing three 5-FU units was successfully maintained in the resulting BS. Solid-state NMR ((29) Si and (13) C) spectroscopy show that the organic fragments of the organo-bridged silane are retained in the hybrid through covalent bonding and the (1) H NMR spectroscopic analysis provides evidence for the hydrogen-bonding interactions between the prodrug bearing three 5-FU units and the triazine-based hybrid matrix. The complex in the BS is not affected under neutral medium and operates under acidic conditions even under pH as high as 5 to deliver the drug as demonstrated by HPLC analysis and confirmed by FTIR and (13) C NMR spectroscopic studies. Such functional BS are promising materials as carriers to avoid the side effects of the anticancer drug 5-FU thanks to a controlled and targeted drug delivery. PMID:23929826

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

    NASA Astrophysics Data System (ADS)

    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.

  9. 49 CFR 237.57 - Designations of individuals.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons... railroad bridge engineers, railroad bridge inspectors and railroad bridge supervisors. Each...

  10. 49 CFR 237.57 - Designations of individuals.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons... railroad bridge engineers, railroad bridge inspectors and railroad bridge supervisors. Each...

  11. 49 CFR 237.57 - Designations of individuals.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons... railroad bridge engineers, railroad bridge inspectors and railroad bridge supervisors. Each...

  12. The Bridges Program.

    ERIC Educational Resources Information Center

    Bohnen, Elizabeth; Klie, Judy

    This report describes BRIDGES, an employment equity special measures training program developed by the City of Toronto (Ontario, Canada). It was designed to help women employees move from their traditional jobs into trades, technical or operation (TTO) jobs within their own organization. The program is a combination of classroom sessions, shop…

  13. Bridging the Gap?

    ERIC Educational Resources Information Center

    Salter, Colin

    2009-01-01

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

  14. 49 CFR 236.713 - Bridge, movable.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

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

  15. 49 CFR 236.713 - Bridge, movable.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

  16. 49 CFR 236.713 - Bridge, movable.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

  17. 49 CFR 236.713 - Bridge, movable.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

  18. 49 CFR 236.713 - Bridge, movable.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  19. Software Bridge

    NASA Technical Reports Server (NTRS)

    1995-01-01

    I-Bridge is a commercial version of software developed by I-Kinetics under a NASA Small Business Innovation Research (SBIR) contract. The software allows users of Windows applications to gain quick, easy access to databases, programs and files on UNIX services. Information goes directly onto spreadsheets and other applications; users need not manually locate, transfer and convert data.

  20. Bridged graphite oxide materials

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

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

  1. Bridge Inspector's Training Manual.

    ERIC Educational Resources Information Center

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

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

  2. Visual Storyboarding Provides a Conceptual Bridge from Research to Development: Students Can Imagine the Results of Their Decision Making, and Their Prioritization of the Many Facets of the Design Problem Will Facilitate the Development of a Strong Final Solution

    ERIC Educational Resources Information Center

    Reeder, Kevin

    2005-01-01

    In order to facilitate the selection/prioritization process and bridge the gap of design research to design conceptualization, students need to visualize the big picture that describes how the research categories such as "user," "marketing," "functional/mechanical research" are related. This is achieved through the use of a visual storyboard. The…

  3. Design, Synthesis and Antitumor Activity of Novel link-bridge and B-Ring Modified Combretastatin A-4 (CA-4) Analogues as Potent Antitubulin Agents.

    PubMed

    Duan, Yong-Tao; Man, Ruo-Jun; Tang, Dan-Jie; Yao, Yong-Fang; Tao, Xiang-Xiang; Yu, Chen; Liang, Xin-Yi; Makawana, Jigar A; Zou, Mei-Juan; Wang, Zhong-Chang; Zhu, Hai-Liang

    2016-01-01

    A series of 12 novel acylhydrazone, chalcone and amide-bridged analogues of combretastatin A-4 were designed and synthesized toward tubulin. All these compounds were determined by elemental analysis, (1)H NMR, and MS. Among them, compound 7 with acylhydrazone-bridge, bearing a benzyl at the indole-N position, was identified as a potent antiproliferative agent against a panel of cancer cell lines with IC50 values ranging from 0.08 to 35.6 μM. In contrast, its cytotoxic effects on three normal human cells were minimal. Cellular studies have revealed that the induction of apoptosis by compound 7 was associated with a collapse of mitochondrial membrane potential, accumulation of reactive oxygen species, alterations in the expression of some cell cycle-related proteins (Cyclin B1, Cdc25c, Cdc2, P21) and some apoptosis-related proteins (Bax, PARP, Bcl-2, Caspase3). The docking mode showed the binding posture of CA-4 and compound 7 are similar in the colchicine-binding pocket of tubulin, as confirmed by colchicine-tubulin competitive binding assay, tubulin polymerization inhibitory activity, extracellular protein expression determination assay and confocal immunofluorescence microscopy. In vivo study, compound 7 effectively inhibited A549 xenograft tumor growth without causing significant loss of body weight suggesting that compound 7 is a promising new antimitotic agent with clinical potential. PMID:27138035

  4. Design, Synthesis and Antitumor Activity of Novel link-bridge and B-Ring Modified Combretastatin A-4 (CA-4) Analogues as Potent Antitubulin Agents

    PubMed Central

    Duan, Yong-Tao; Man, Ruo-Jun; Tang, Dan-Jie; Yao, Yong-Fang; Tao, Xiang-Xiang; Yu, Chen; Liang, Xin-Yi; Makawana, Jigar A.; Zou, Mei-Juan; Wang, Zhong-Chang; Zhu, Hai-Liang

    2016-01-01

    A series of 12 novel acylhydrazone, chalcone and amide–bridged analogues of combretastatin A-4 were designed and synthesized toward tubulin. All these compounds were determined by elemental analysis, 1H NMR, and MS. Among them, compound 7 with acylhydrazone-bridge, bearing a benzyl at the indole-N position, was identified as a potent antiproliferative agent against a panel of cancer cell lines with IC50 values ranging from 0.08 to 35.6 μM. In contrast, its cytotoxic effects on three normal human cells were minimal. Cellular studies have revealed that the induction of apoptosis by compound 7 was associated with a collapse of mitochondrial membrane potential, accumulation of reactive oxygen species, alterations in the expression of some cell cycle-related proteins (Cyclin B1, Cdc25c, Cdc2, P21) and some apoptosis-related proteins (Bax, PARP, Bcl-2, Caspase3). The docking mode showed the binding posture of CA-4 and compound 7 are similar in the colchicine-binding pocket of tubulin, as confirmed by colchicine-tubulin competitive binding assay, tubulin polymerization inhibitory activity, extracellular protein expression determination assay and confocal immunofluorescence microscopy. In vivo study, compound 7 effectively inhibited A549 xenograft tumor growth without causing significant loss of body weight suggesting that compound 7 is a promising new antimitotic agent with clinical potential. PMID:27138035

  5. 49 CFR 237.51 - Railroad bridge engineers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.51 Railroad bridge engineers. (a) A railroad bridge engineer shall be a person who is determined... 49 Transportation 4 2014-10-01 2014-10-01 false Railroad bridge engineers. 237.51 Section...

  6. 49 CFR 237.51 - Railroad bridge engineers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.51 Railroad bridge engineers. (a) A railroad bridge engineer shall be a person who is determined... 49 Transportation 4 2013-10-01 2013-10-01 false Railroad bridge engineers. 237.51 Section...

  7. 49 CFR 237.55 - Railroad bridge supervisors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.55 Railroad bridge supervisors. A railroad bridge supervisor shall be a person, regardless of... 49 Transportation 4 2010-10-01 2010-10-01 false Railroad bridge supervisors. 237.55 Section...

  8. 49 CFR 237.55 - Railroad bridge supervisors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.55 Railroad bridge supervisors. A railroad bridge supervisor shall be a person, regardless of... 49 Transportation 4 2013-10-01 2013-10-01 false Railroad bridge supervisors. 237.55 Section...

  9. 49 CFR 237.53 - Railroad bridge inspectors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.53 Railroad bridge inspectors. A railroad bridge inspector shall be a person who is determined by... 49 Transportation 4 2013-10-01 2013-10-01 false Railroad bridge inspectors. 237.53 Section...

  10. 49 CFR 237.55 - Railroad bridge supervisors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.55 Railroad bridge supervisors. A railroad bridge supervisor shall be a person, regardless of... 49 Transportation 4 2014-10-01 2014-10-01 false Railroad bridge supervisors. 237.55 Section...

  11. 49 CFR 237.53 - Railroad bridge inspectors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.53 Railroad bridge inspectors. A railroad bridge inspector shall be a person who is determined by... 49 Transportation 4 2014-10-01 2014-10-01 false Railroad bridge inspectors. 237.53 Section...

  12. 49 CFR 237.53 - Railroad bridge inspectors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.53 Railroad bridge inspectors. A railroad bridge inspector shall be a person who is determined by... 49 Transportation 4 2010-10-01 2010-10-01 false Railroad bridge inspectors. 237.53 Section...

  13. 49 CFR 237.51 - Railroad bridge engineers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.51 Railroad bridge engineers. (a) A railroad bridge engineer shall be a person who is determined... 49 Transportation 4 2010-10-01 2010-10-01 false Railroad bridge engineers. 237.51 Section...

  14. 25 CFR 170.507 - Who reviews bridge inspection reports?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Who reviews bridge inspection reports? 170.507 Section... ROADS PROGRAM Planning, Design, and Construction of Indian Reservation Roads Program Facilities Bridge Inspection § 170.507 Who reviews bridge inspection reports? The person responsible for the bridge...

  15. 25 CFR 170.507 - Who reviews bridge inspection reports?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Who reviews bridge inspection reports? 170.507 Section 170... ROADS PROGRAM Planning, Design, and Construction of Indian Reservation Roads Program Facilities Bridge Inspection § 170.507 Who reviews bridge inspection reports? The person responsible for the bridge...

  16. 25 CFR 170.507 - Who reviews bridge inspection reports?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Who reviews bridge inspection reports? 170.507 Section... ROADS PROGRAM Planning, Design, and Construction of Indian Reservation Roads Program Facilities Bridge Inspection § 170.507 Who reviews bridge inspection reports? The person responsible for the bridge...

  17. 25 CFR 170.507 - Who reviews bridge inspection reports?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Who reviews bridge inspection reports? 170.507 Section... ROADS PROGRAM Planning, Design, and Construction of Indian Reservation Roads Program Facilities Bridge Inspection § 170.507 Who reviews bridge inspection reports? The person responsible for the bridge...

  18. 25 CFR 170.507 - Who reviews bridge inspection reports?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Who reviews bridge inspection reports? 170.507 Section... ROADS PROGRAM Planning, Design, and Construction of Indian Reservation Roads Program Facilities Bridge Inspection § 170.507 Who reviews bridge inspection reports? The person responsible for the bridge...

  19. Steel bridge retrofit evaluation

    NASA Astrophysics Data System (ADS)

    Prine, David W.

    1998-03-01

    The development of a retrofit design aimed at retarding or eliminating fatigue crack growth in a large bridge can be a very difficult and expensive procedure. Analytical techniques frequently do not provide sufficient accuracy when applied to complex structural details. The Infrastructure Technology Institute (ITI) of Northwestern University, under contract to the California Department of Transportation (Caltrans), recently applied experimental state-of-the-art NDE technology to the Interstate 80 bridge over the Sacramento River near Sacramento, California (Bryte Bend). Acoustic emission monitoring was applied in conjunction with strain gage monitoring to aid in characterizing the retrofits' effect on existing active fatigue cracks. The combined test results clearly showed that one retrofit design was superior to the other.

  20. Rational design, synthesis, and biological evaluation of lactam-bridged gramicidin A analogues: discovery of a low-hemolytic antibacterial peptide.

    PubMed

    Mao, Ji; Kuranaga, Takefumi; Hamamoto, Hiroshi; Sekimizu, Kazuhisa; Inoue, Masayuki

    2015-03-01

    A linear peptide, gramicidin A (GA), folds into a β(6.3) -helix, functions as an ion channel in the cell membrane, and exerts antibacterial activity. Herein we describe the rational design, synthesis, and biological evaluation of lactam-bridged GA analogues. The GA analogue with a 27-membered macrolactam was found to adopt a stable β(6.3) -helical conformation and exhibits higher ion-exchange activity than GA. Furthermore, this GA analogue retains the potent antibiotic activity of GA, but its hemolytic activity and toxicity toward mammalian cells are significantly lower than those of GA. This study thus dissociates the antibacterial and hemolytic/cytotoxic activities of GA, and charts a rational path forward for the development of new ion-channel-based antibiotics. PMID:25510221

  1. FROM "CANAL BRIDGE, F.A.P. 4C, MAR. 1938." SHOWING WAIKELE BRIDGE ...

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

    FROM "CANAL BRIDGE, F.A.P. 4-C, MAR. 1938." SHOWING WAIKELE BRIDGE PLAN AND ELEVATION. Hawaii Department of Transportation, Design Branch, Project ID 7101-001, drawing 4449.27. - Waikele Canal Bridge and Highway Overpass, Farrington Highway and Waikele Stream, Waipahu, Honolulu County, HI

  2. Removal of failed crown and bridge

    PubMed Central

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

    2012-01-01

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

  3. Design, fabrication, and characterization of a planar, silicon-based, monolithically integrated micro laminar flow fuel cell with a bridge-shaped microchannel cross-section

    NASA Astrophysics Data System (ADS)

    López-Montesinos, P. O.; Yossakda, N.; Schmidt, A.; Brushett, F. R.; Pelton, W. E.; Kenis, P. J. A.

    2011-05-01

    We report the fabrication of a planar, silicon-based, monolithically integrated micro laminar flow fuel cell (μLFFC) using standard MEMS and IC-compatible fabrication technologies. The μLFFC operates with acid supported solutions of formic acid and potassium permanganate, as a fuel and oxidant respectively. The micro-fuel cell design features two in-plane anodic and cathodic microchannels connected via a bridge to confine the diffusive liquid-liquid interface away from the electrode areas and to minimize crossover. Palladium high-active-surface-area catalyst was selectively integrated into the anodic microchannel by electrodeposition, whereas no catalyst was required in the cathodic microchannel. A three-dimensional (3D) diffusion-convection model was developed to study the behavior of the diffusion zone and to extract appropriate cell-design parameters and operating conditions. Experimentally, we observed peak power densities as high as 26 mW cm-2 when operating single cells at a flow rate of 60 μL min-1 at room temperature. The miniature membraneless fuel cell design presented herein offers potential for on-chip power generation, which has long been prohibited by integration complexities associated with the membrane.

  4. [Retention of adhesive bridges].

    PubMed

    Raes, F; De Boever, J

    1994-04-01

    Since the development of adhesive bridges in the early seventies, the retention and therefore the durability of these bridges has been tremendously improved. Conditioning of the non-precious metal by silanisation, careful acid etching of the enamel and the use of the appropriate composite resin are of prime importance. Furthermore, the meticulous preparation with enough interproximal embrace, occlusal rests, interocclusal clearance and cingulum stops is equally important. Including more teeth in the design does not necessarily lead to an improved retention. Besides the material and technical aspects, the whole clinical procedure needs much attention. The retention does not depend on one single factor, but on the precision of all the necessary clinical steps and on a well-defined selection of the material. In this way a five-year survival rate of close to 80% can be obtained. PMID:11830965

  5. Bridging the Field Trip Gap: Integrating Web-Based Video as a Teaching and Learning Partner in Interior Design Education

    ERIC Educational Resources Information Center

    Roehl, Amy

    2013-01-01

    This study utilizes web-based video as a strategy to transfer knowledge about the interior design industry in a format that interests the current generation of students. The model of instruction developed is based upon online video as an engaging, economical, and time-saving alternative to a field trip, guest speaker, or video teleconference.…

  6. Impact of cross-tie design on the in-plane stiffness and local mode formation of cable networks on cable-stayed bridges

    NASA Astrophysics Data System (ADS)

    Ahmad, Javaid; Cheng, Shaohong; Ghrib, Faouzi

    2016-02-01

    Suppressing unfavorable stay cable vibrations using cross-ties is becoming more popular on cable-stayed bridges though the mechanics of the formed cable network is yet fully understood. In practice, the main task in designing cross-ties or cable networks is to choose the cross-tie installation location, stiffness and number based on the main cable properties in the network. To have a more comprehensive picture of how to choose these design parameters to achieve higher in-plane network stiffness while minimizing the number of excited local modes, it is imperative to examine dynamic behavior of cable networks with general configurations. In the current study, an analytical model of a general cable network consisting of multiple main cables interconnected by multiple lines of transverse flexible cross-ties will be developed. A new term, defined as the local mode cluster, will be introduced to assess the severity of local mode excitation. Criteria for identifying the presence of local mode cluster will be proposed. A parametric study will be conducted to evaluate the impact of cross-tie installation location, stiffness and number on the network modal response. Results obtained from the present study will provide deeper insight into the selection of these system parameters to achieve the combined benefits of increasing network in-plane stiffness and minimizing the excitation of local modes.

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

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

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

  8. Anticoagulation After Cardioembolic Stroke: To Bridge or Not to Bridge?

    PubMed Central

    Hallevi, Hen; Albright, Karen C.; Martin-Schild, Sheryl; Barreto, Andrew D.; Savitz, Sean I.; Escobar, Miguel A.; Gonzales, Nicole R.; Noser, Elizabeth A.; Illoh, Kachi; Grotta, James C.

    2009-01-01

    Background Most patients with cardioembolic stroke require long-term anticoagulation. Still, uncertainty exists regarding the best mode of starting long-term anticoagulation. Design, Setting, and Patients We conducted a retrospective review of all patients with cardioembolic stroke admitted to our center from April 1, 2004, to June 30, 2006, and not treated with tissue plasminogen activator. Patients were grouped by treatment: no treatment, aspirin only, aspirin followed by warfarin sodium, intravenous heparin sodium in the acute phase followed by warfarin (heparin bridging), and full-dose enoxaparin sodium combined with warfarin (enoxaparin bridging). Outcome measures and adverse events were collected prospectively. Laboratory values were captured from the records. Main Outcome Measures Symptomatic hemorrhagic transformation, stroke progression, and discharge modified Rankin Scale score. Results Two hundred four patients were analyzed. Recurrent stroke occurred in 2 patients (1%). Progressive stroke was the most frequent serious adverse event, seen in 11 patients (5%). Hemorrhagic transformation occurred in a bimodal distribution—an early benign hemorrhagic transformation and a late symptomatic hemorrhagic transformation. All of the symptomatic hemorrhagic transformation cases were in the enoxaparin bridging group (10%) (P=.003). Systemic bleeding occurred in 2 patients (1%) and was associated with heparin bridging (P=.04). Conclusions Anticoagulation of patients with cardioembolic stroke can be safely started with warfarin shortly after stroke. Heparin bridging and enoxaparin bridging increase the risk for serious bleeding. PMID:18625852

  9. [Retention of adhesive bridges].

    PubMed

    Raes, F; De Boever, J

    1990-01-01

    Since the development of adhesive bridges in the early seventies, the retention and therefore the durability of these bridges has been tremendously improved. To ensure an adequate retention over a number of years different factors have to be considered. Conditioning of the non-precious metal by silanisation, careful acid etching of the enamel and the use of the appropriate composite resin (Panavia Ex) are of prime importance. Furthermore, the meticulous preparation with enough interproximal embrace, occlusal rets, interocclusal clearance of 0.4 mm and cingulum stops is equally important. Care should be taken not to remove all the enamel in the cervical region in preparing a mini chamfer. Including more teeth in the design does not necessarily lead to an improved retention. Teeth with a different mobility should not be included in the same bridge. Besides the material and technical aspects, the whole clinical procedure needs much attention. Only an exact impression, a precise model and a reliable casting technique will provide a metal frame with an optimal marginal adaptation and a close fit. The retention does not depend on one single factor but on the precision of all the necessary clinical steps and on a well-defined selection of the material. In this way a five-year survival rate of close to 90% can be obtained. PMID:2077574

  10. Design, development and characterization of an x-band 5 bit DMTL phase shifter using an inline MEMS bridge and MAM capacitors

    NASA Astrophysics Data System (ADS)

    Dey, Sukomal; Koul, Shiban K.

    2014-09-01

    A radio frequency micro-electro-mechanical system (RF-MEMS) 5 bit phase shifter based on a distributed MEMS transmission line concept with excellent phase accuracy and good repeatability is presented in this paper. The phase shifter is built with three fixed-fixed beams; one is switchable with electrostatic actuation and the other two are fixed for a metal-air-metal (MAM) capacitor. The design is based on a coplanar waveguide (CPW) configuration using alumina substrate. Gold-based surface micromachining is used to develop the individual primary phase bits (11.25°/22.5°/45°/90°/180°), which are fundamental building blocks of the complete 5 bit phase shifter. All of the primary phase bits are cascaded together to build the complete phase shifter. Detailed design methodology and performance analysis of the unit cell phase shifter has been carried out with structural and parametric optimization using an in-line bridge and MAM capacitors. The mechanical, electrical, transient, intermodulation distortion (IMD), temperature distribution, power handling and loss performances of the MEMS bridge have been experimentally obtained and validated using simulations up to reasonable extent. A single unit cell is able to provide 31 dB return loss, maximum insertion loss of 0.085 dB and a differential phase shift of 5.95° (at 10 GHz) over the band of interest. Furthermore, all primary phase bits are individually tested to ensure overall optimum phase shifter performance. The complete 5 bit phase shifter demonstrates an average insertion loss of 4.72 dB with return loss of better than 12 dB within 8-12 GHz using periodic placement of 62 unit cells and a maximum phase error of ±3.2° has been obtained at 10 GHz. Finally, the x-band 5 bit phase shifter is compared with the present state-of-the-art. The performance of the 5 bit phase shifter when mounted inside a test jig has been experimentally investigated and the results are presented. The total area of

  11. Sacrificial bridges for MEMS fabrication

    NASA Astrophysics Data System (ADS)

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

    2011-09-01

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

  12. Bridging the ';knowing and doing gap' in disaster risk reduction using design and design thinking; Ideation of concepts to improve hazard preparedness and response

    NASA Astrophysics Data System (ADS)

    van Manen, S. M.

    2013-12-01

    The central goal of disaster risk reduction (DRR) is to reduce the impact and cost of natural hazards, in human, environmental and economic terms. There are numerous approaches that aim to achieve this but recent studies have shown a substantial gap between risk reduction actions taken at national and local levels. The traditional media of the scientist: education, outreach and increasingly community involvement, have been shown to raise levels of awareness and understanding but generate little change in terms of people's actions. This can be attributed to the differences in hazard perception and the relative weight placed on various aspects by scientists, authorities and communities as a result of non-hazard related factors. Therefore DRR, particularly when placed in its social, environmental and economic contexts, is an excellent example of what is termed a ';wicked problem': a problem that is difficult to formulate, where data to base decisions on are incomplete, the stakeholders are many and they hold contradicting views and the consequences of actions on the wider system are unclear. Although both science and design are geared towards problem solving, design, in drawing equally on art and engineering skills, does so in a fundamentally different but complementary way. Neither design nor science will solve the wicked problem that is DRR, but scientists, engineers and designers can improve the current state of disaster risk reduction by tackling aspects of underlying risk factors. This work will present concepts aimed at engaging people in novel and innovative ways with scientific results, with a specific focus on improving hazard preparedness and tangible, rather than abstract, ways of communicating hazard levels. Key considerations include the need to graft onto existing behaviours or innovate on existing products to simplify implementation, the possibility to co-create and connect through design and balancing desirability with technical and economical

  13. 46 CFR 108.801 - Navigation bridge visibility.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Navigation bridge visibility. 108.801 Section 108.801 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Navigation Bridge Visibility § 108.801 Navigation bridge visibility. Each mobile offshore drilling unit which is 100 meters...

  14. 46 CFR 108.801 - Navigation bridge visibility.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Navigation bridge visibility. 108.801 Section 108.801 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Navigation Bridge Visibility § 108.801 Navigation bridge visibility. Each mobile offshore drilling unit which is 100 meters...

  15. 49 CFR 237.55 - Railroad bridge supervisors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Railroad bridge supervisors. 237.55 Section 237.55 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.55 Railroad bridge...

  16. 49 CFR 237.53 - Railroad bridge inspectors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Railroad bridge inspectors. 237.53 Section 237.53 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.53 Railroad bridge...

  17. 49 CFR 237.51 - Railroad bridge engineers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Railroad bridge engineers. 237.51 Section 237.51 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.51 Railroad bridge engineers....

  18. 49 CFR 237.53 - Railroad bridge inspectors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Railroad bridge inspectors. 237.53 Section 237.53 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.53 Railroad bridge...

  19. 49 CFR 237.51 - Railroad bridge engineers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Railroad bridge engineers. 237.51 Section 237.51 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.51 Railroad bridge engineers....

  20. 49 CFR 237.55 - Railroad bridge supervisors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Railroad bridge supervisors. 237.55 Section 237.55 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION BRIDGE SAFETY STANDARDS Qualifications and Designations of Responsible Persons § 237.55 Railroad bridge...

  1. A data management infrastructure for bridge monitoring

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

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

  2. Liquid bridges with thermocapillarity

    NASA Technical Reports Server (NTRS)

    Xu, J.-J.; Davis, S. H.

    1983-01-01

    An axisymmetric liquid bridge is subjected to an axial temperature gradient. Thermal variations in surface tension drive a motion that is described using lubrication theory for slender bridges. At leading order in aspect ratio, a class of similarity solutions is obtained valid in the core region away from the endwalls of the bridge. These solutions describe the flows, temperature fields, and interfacial shapes of bridges that may sustain substantial interfacial deflections.

  3. 12. DETAIL VIEW OF BRIDGE, SHOWING SPRING LINE OF SPANS ...

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

    12. DETAIL VIEW OF BRIDGE, SHOWING SPRING LINE OF SPANS FROM CROWN OF MID-CHANNEL PIER, PAIRED COLUMNS SUPPORTING DECK, ARCHED WINDOW RAILING, LOOKING WEST-NORTHWEST FROM EUREKA SOUTHERN RAILROAD BRIDGE. CABLES VISIBLE IN BACKGROUND ARE EARTHQUAKE RESTRAINERS RETROFITTED TO 1952 HIGHWAY BRIDGE, WHICH FUNCTIONED AS DESIGNED IN APRIL 1992 TEMBLOR - Van Duzen River Bridge, Spanning Van Duzen River at CA State Highway 101, Alton, Humboldt County, CA

  4. Halliburton Composite Bridge Plug Assembly

    SciTech Connect

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

    2005-01-15

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

  5. [A newly designed salt bridge cap-type, a variable, and non-invasive EEG lead electrode and the analytical power spectrum].

    PubMed

    Ohsawa, K; Mikawa, J

    1992-03-01

    A newly devised, variable EEG cap-style electrode that has an electrical salt bridge with 2% agarose gel and 5% NaCl solution was developed. The number of electrodes can be increased as required. The weight of 15 electrodes is about 100g. The electrode is simple, fast and in a one-touch form for measuring the EEG. An EEG using this electrode system was recorded in a healthy man in a sitting position on a chair, at rest, and with eyes closed. The power spectrum showed different patterns for the power at different concentrations of aqueous solution in the matrix of the salt bridge. The power changed to a pattern of J-type with 20% NaCl solution, to a pattern of U-type with 5% NaCl solution, and to a pattern of L-type with 0.9% NaCl solution, respectively. The matrix of the salt bridge that has a concentration higher than 0.9% NaCl, is a hypertonic solution for the isotonic body liquid. One person felt pain in half of the part of the experiment when a 20% NaCl hypertonic solution was applied to the scalp, so a 20% NaCl solution of the salt bridge was used in experiments concerning osmosis. When a salt bridge of 5% NaCl solution was used, the same results of the wave measurement was obtained 10 times. It was a value close to the expected measurement so it has a high probability of being correct. At this time the power spectrum shows a U-type pattern consistently. PMID:1591099

  6. Violin Bridge Mobility Analysis under In-Plane Excitation

    PubMed Central

    Zhang, Cheng-Zhong; Zhang, Guang-Ming; Ye, Bang-Yan; Liang, Li-Dong

    2013-01-01

    The vibration of a violin bridge is a dynamic contact vibration with two interfaces: strings-bridge, and bridge feet-top plate. In this paper, the mobility of an isolated bridge under in-plane excitation is explored using finite element modeling based on the contact vibration model. Numerical results show that the dynamic contact stiffness in the two contact interfaces has a great impact on the bridge mobility. A main resonance peak is observed in the frequency range of 2–3 kHz in the frequency response of the isolated bridge when the contact stiffness is smaller than a critical threshold. The main resonance peak frequency is affected by the contact stiffness as well. In order to verify the numerical findings, a novel experimental system is then designed on the basis of a piezoelectric dynamometer for bridge mobility analysis. Experimental results confirm the impact of the dynamic contact stiffness on the bridge mobility. PMID:24217354

  7. Violin bridge mobility analysis under in-plane excitation.

    PubMed

    Zhang, Cheng-Zhong; Zhang, Guang-Ming; Ye, Bang-Yan; Liang, Li-Dong

    2013-01-01

    The vibration of a violin bridge is a dynamic contact vibration with two interfaces: strings-bridge, and bridge feet-top plate. In this paper, the mobility of an isolated bridge under in-plane excitation is explored using finite element modeling based on the contact vibration model. Numerical results show that the dynamic contact stiffness in the two contact interfaces has a great impact on the bridge mobility. A main resonance peak is observed in the frequency range of 2-3 kHz in the frequency response of the isolated bridge when the contact stiffness is smaller than a critical threshold. The main resonance peak frequency is affected by the contact stiffness as well. In order to verify the numerical findings, a novel experimental system is then designed on the basis of a piezoelectric dynamometer for bridge mobility analysis. Experimental results confirm the impact of the dynamic contact stiffness on the bridge mobility. PMID:24217354

  8. Salt-Bridge Energetics in Halophilic Proteins

    PubMed Central

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

    2014-01-01

    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

  9. 49 CFR 237.131 - Design.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... TRANSPORTATION BRIDGE SAFETY STANDARDS Repair and Modification of Bridges § 237.131 Design. Each repair or modification which materially modifies the capacity of a bridge or the stresses in any primary load-carrying component of a bridge shall be designed by a railroad bridge engineer. The design shall specify the...

  10. 49 CFR 237.131 - Design.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... TRANSPORTATION BRIDGE SAFETY STANDARDS Repair and Modification of Bridges § 237.131 Design. Each repair or modification which materially modifies the capacity of a bridge or the stresses in any primary load-carrying component of a bridge shall be designed by a railroad bridge engineer. The design shall specify the...

  11. 49 CFR 237.131 - Design.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... TRANSPORTATION BRIDGE SAFETY STANDARDS Repair and Modification of Bridges § 237.131 Design. Each repair or modification which materially modifies the capacity of a bridge or the stresses in any primary load-carrying component of a bridge shall be designed by a railroad bridge engineer. The design shall specify the...

  12. Partially entangled states bridge in quantum teleportation

    NASA Astrophysics Data System (ADS)

    Cai, Xiao-Fei; Yu, Xu-Tao; Shi, Li-Hui; Zhang, Zai-Chen

    2014-10-01

    The traditional method for information transfer in a quantum communication system using partially entangled state resource is quantum distillation or direct teleportation. In order to reduce the waiting time cost in hop-by-hop transmission and execute independently in each node, we propose a quantum bridging method with partially entangled states to teleport quantum states from source node to destination node. We also prove that the designed specific quantum bridging circuit is feasible for partially entangled states teleportation across multiple intermediate nodes. Compared to two traditional ways, our partially entanglement quantum bridging method uses simpler logic gates, has better security, and can be used in less quantum resource situation.

  13. Imaging radar for bridge deck inspection

    SciTech Connect

    Warhus, J.; Mast, J.; Nelson, S.

    1995-04-13

    Lawrence Livermore National Laboratory (LLNL)l is developing a prototype imaging radar for inspecting steel reinforced concrete bridge decks. The system is designed to acquire Synthetic Aperture Radar (SAR) data and provide high-resolution images of internal structure, flaws, and defects enabling bridge inspectors to nondestructively evaluate and characterize bridge deck condition. Concrete delamination resulting from corrosion of steel reinforcing bars (rebars) is an important structural defect that the system is designed to detect. The prototype system uses arrays of compact, low-cost Micropower Impulse Radar (MIR) modules, supported by appropriate data acquisition and storage subsystems, to generate and collect the radar data, and unique imaging codes to reconstruct images of bridge deck internals. In this paper, we provide an overview of the prototype system concept, discuss its expected performance, and present recent experimental results showing the capability of this approach to detect thin delamination simulations embedded in concrete.

  14. Galactic Bridges in Pairs

    NASA Astrophysics Data System (ADS)

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

    2016-01-01

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

  15. Semiconductor bridge (SCB) detonator

    DOEpatents

    Bickes, Jr., Robert W.; 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.

  16. Semiconductor bridge (SCB) detonator

    DOEpatents

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

    1999-01-19

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

  17. Automation of Resistance Bridge Calibrator

    NASA Astrophysics Data System (ADS)

    Podgornik, Tadej; Bojkovski, Jovan; Batagelj, Valentin; Drnovšek, Janko

    2008-02-01

    The article addresses the automation of the resistance bridge calibrator (RBC). The automation of the RBC is performed in order to facilitate the operation of the RBC, improve the reliability, and enable several additional possibilities compared to the tedious manual operation, thereby making the RBC a more practical device for routine use. The RBC is used to calibrate AC and DC resistance bridges, which are mainly used in a primary thermometry laboratory. It consists of a resistor network made up from four main resistors from which 35 different resistance values can be realized using toggle switches. Literature shows that the resistors’ non-zero temperature coefficient can influence the measurements, causing difficulties when calibrating resistance bridges with low uncertainty. Placing the RBC in a thermally stable environment can reduce this, but it does not solve the problem of the time-consuming manual selection of the resistance values. To solve this, an automated means to manipulate the switches, while the device is placed within a thermally stable environment, was created. Computer operation completely substitutes for any manual operation during which an operator would normally have to be present. The computer also acquires measurements from the bridge. In this way, repeated and reproducible calibration measurements inside a temperature-stable environment can be carried out with no active involvement of personnel. The automation process itself was divided into several stages. They included the construction of a servo-manipulator to move the switches, the design of a dedicated electronic controller that also provides a serial interface (RS-232) to the computer, and the development of custom computer software to configure the servo-manipulator and control the calibration process. Measurements show that automation does not affect the long-term stability and mechanical repeatability of the RBC. The repeatability and reproducibility of bridge calibration ratios

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

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

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

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

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

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

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

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

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

  1. 2. LONG VIEW NORTHWEST, EASTBOUND BRIDGE IN FOREGROUND, WESTBOUND BRIDGE ...

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

    2. LONG VIEW NORTHWEST, EASTBOUND BRIDGE IN FOREGROUND, WESTBOUND BRIDGE IN BACKGROUND - Willow Run Expressway Bridge No. R01, Spanning Conrail Railway, eastbound, at US-10, Ypsilanti, Washtenaw County, MI

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

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

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

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

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

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

  4. 11. Southern bridge abutment and arches, taken from old bridge ...

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

    11. Southern bridge abutment and arches, taken from old bridge abutment looking south. - Presumpscot Falls Bridge, Spanning Presumptscot River at Allen Avenue extension, 0.75 mile west of U.S. Interstate 95, Falmouth, Cumberland County, ME

  5. VIEW OF APALACHICOLA RIVER BRIDGE STEEL BRIDGE TRUSS AND ROADWAY ...

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

    VIEW OF APALACHICOLA RIVER BRIDGE STEEL BRIDGE TRUSS AND ROADWAY AT PIER 3, EAST SIDE, FROM RIVER, FACING WEST - Apalachicola River Bridge, State Route 20 spanning the Apalachicola River, Blountstown, Calhoun County, FL

  6. 3. View of Clark Fork Vehicle Bridge facing southwest. Bridge ...

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

    3. View of Clark Fork Vehicle Bridge facing southwest. Bridge from north shore of Clark Fork River. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  7. 4. View of Clark Fork Vehicle Bridge facing northeast. Bridge ...

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

    4. View of Clark Fork Vehicle Bridge facing northeast. Bridge from south shoreof Clark Fork River showing 4 spans. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  8. 2. View of Clark Fork Vehicle Bridge facing northeast. Bridge ...

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

    2. View of Clark Fork Vehicle Bridge facing northeast. Bridge from south shore of Clark Fork River showing 4 1/2 spans. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  9. 7. View of Clark Fork Vehicle Bridge facing northwest. Bridge ...

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

    7. View of Clark Fork Vehicle Bridge facing northwest. Bridge from south shore of Clark Fork River showing 4 1/2 spans. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  10. TWIN SKEWED TRUSS RAILROAD BRIDGES NEAR BRIDGE STREET AT THE ...

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

    TWIN SKEWED TRUSS RAILROAD BRIDGES NEAR BRIDGE STREET AT THE WEST END OF THE PLANT. THIS VIEW PROBABLY LOOKING NORTHWEST. BRIDGES BUILT OVER ERIE CANAL (WHICH FLOWED RIGHT THROUGH THE MIDDLE OF THE PLANT) BY AMERICAN BRIDGE COMPANY IN 1902. SINCE THIS PHOTO WAS TAKEN, NEAR BRIDGE HAS BEEN DEMOLISHED; FAR BRIDGE IS STILL IN SERVICE. - Solvay Process Company, Between Willis & Milton Avenues, Solvay, Onondaga County, NY

  11. Precision bolometer bridge

    NASA Technical Reports Server (NTRS)

    White, D. R.

    1968-01-01

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

  12. Active-bridge oscillator

    DOEpatents

    Wessendorf, Kurt O.

    2001-01-01

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

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

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

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

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

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

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

  15. Sulphite Railroad Bridge1896, Title Sheet Sulphite Railroad Bridge, Former ...

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

    Sulphite Railroad Bridge-1896, Title Sheet - Sulphite Railroad Bridge, Former Boston & Maine Railroad (originally Tilton & Franklin Railroad) spanning Winnipesautee River, Franklin, Merrimack County, NH

  16. Test and evaluation plan for the composite bridge

    SciTech Connect

    Rodriguez, J.G.; Dumlao, C.; Ciolko, A.T.; Pfister, T.J.; Schmeckpeper, E.R.

    1997-04-01

    Polymer matrix composites (PMC) are entering the nation`s infrastructure as alternatives to conventional materials. Working with the Federal Highway Administration and Department of Energy, the Idaho National Engineering and Environmental Laboratory is testing and evaluating a PMC structure for use in bridge rehabilitation and replacement. A 30-foot PMC bridge, designed and built by Lockheed Martin Missile and Space, will be field tested in Idaho. The design of this bridge represents simple support bridges in the 120-foot span category. This report describes the construction, transportation, installation, testing, and material properties for this PMC structure.

  17. 5. View of Clark Fork Vehicle Bridge facing east. Bridge ...

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

    5. View of Clark Fork Vehicle Bridge facing east. Bridge from south shore of Clark Fork River-southernmost span. 1900-era Northern Pacific Railway Bridge in background. - Clark Fork Vehicle Bridge, Spanning Clark Fork River, serves Highway 200, Clark Fork, Bonner County, ID

  18. Bridging the Gap between User Experience Research and Design in Industry: An Analysis of Two Common Communication Tools--Personas and Scenarios

    ERIC Educational Resources Information Center

    Putnam, Cynthia

    2010-01-01

    User experience (UX) research in the design of technology products utilizes human-centered design (HCD) methods to summarize and explain pertinent information about end users to designers. However, UX researchers cannot effectively communicate the needs and goals of users if designers do not find UX research (a) easy to integrate into design…

  19. [The multiple promontory bridge].

    PubMed

    Wysocki, J

    1998-01-01

    Anatomical investigations of one hundred human temporal bones revealed a significant variability of the promontory bridge (ponticulus promontorii). In twelve bones double and in two-triple promontory bridge was observed. The triple promontory bridge had not been previously described in available literature. In all the cases the double or triple promontory bridges were observed only on the temporal bones obtained from cadavers of up to four years of age. It confirms previous statements suggesting that development of this structure is connected with the process of pneumatization of the statements suggesting that development of this structure is connected with the process of pneumatization of the temporal bone, which obviously starts in 3-4 year of life. PMID:9884587

  20. Multivariate Feature Selection for Predicting Scour-Related Bridge Damage using a Genetic Algorithm

    NASA Astrophysics Data System (ADS)

    Anderson, I.

    2015-12-01

    Scour and hydraulic damage are the most common cause of bridge failure, reported to be responsible for over 60% of bridge failure nationwide. Scour is a complex process, and is likely an epistatic function of both bridge and stream conditions that are both stationary and in dynamic flux. Bridge inspections, conducted regularly on bridges nationwide, rate bridge health assuming a static stream condition, and typically do not include dynamically changing geomorphological adjustments. The Vermont Agency of Natural Resources stream geomorphic assessment data could add value into the current bridge inspection and scour design. The 2011 bridge damage from Tropical Storm Irene served as a case study for feature selection to improve bridge scour damage prediction in extreme events. The bridge inspection (with over 200 features on more than 300 damaged and 2,000 non-damaged bridges), and the stream geomorphic assessment (with over 300 features on more than 5000 stream reaches) constitute "Big Data", and together have the potential to generate large numbers of combined features ("epistatic relationships") that might better predict scour-related bridge damage. The potential combined features pose significant computational challenges for traditional statistical techniques (e.g., multivariate logistic regression). This study uses a genetic algorithm to perform a search of the multivariate feature space to identify epistatic relationships that are indicative of bridge scour damage. The combined features identified could be used to improve bridge scour design, and to better monitor and rate bridge scour vulnerability.

  1. The Interstate-40 bridge shaker project

    SciTech Connect

    Mayes, R.L.; Nusser, M.A.

    1994-04-01

    New Mexico State University organized an effort to perform static and dynamic damage-detection tests on the Interstate-40 bridge over the Rio Grande at Albuquerque. The opportunity was available because the 425-ft-long bridge was soon to be replaced. Sandia National Laboratories was asked to provide and operate a shaker that could exert 1000-lb peak amplitude forces for both sinusoidal and random excitations between 2 and 20 Hz. Two Sandia departments collaborated to design and build the shaker, using existing major components connected with Sandia-designed and -fabricated hardware. The shaker was installed and operated successfully for a series of five modal and sinusoidal response tests.

  2. A cloud-based information repository for bridge monitoring applications

    NASA Astrophysics Data System (ADS)

    Jeong, Seongwoon; Zhang, Yilan; Hou, Rui; Lynch, Jerome P.; Sohn, Hoon; Law, Kincho H.

    2016-04-01

    This paper describes an information repository to support bridge monitoring applications on a cloud computing platform. Bridge monitoring, with instrumentation of sensors in particular, collects significant amount of data. In addition to sensor data, a wide variety of information such as bridge geometry, analysis model and sensor description need to be stored. Data management plays an important role to facilitate data utilization and data sharing. While bridge information modeling (BrIM) technologies and standards have been proposed and they provide a means to enable integration and facilitate interoperability, current BrIM standards support mostly the information about bridge geometry. In this study, we extend the BrIM schema to include analysis models and sensor information. Specifically, using the OpenBrIM standards as the base, we draw on CSI Bridge, a commercial software widely used for bridge analysis and design, and SensorML, a standard schema for sensor definition, to define the data entities necessary for bridge monitoring applications. NoSQL database systems are employed for data repository. Cloud service infrastructure is deployed to enhance scalability, flexibility and accessibility of the data management system. The data model and systems are tested using the bridge model and the sensor data collected at the Telegraph Road Bridge, Monroe, Michigan.

  3. Theoretical mechanics: Crowd synchrony on the Millennium Bridge

    NASA Astrophysics Data System (ADS)

    Strogatz, Steven H.; Abrams, Daniel M.; McRobie, Allan; Eckhardt, Bruno; Ott, Edward

    2005-11-01

    Soon after the crowd streamed on to London's Millennium Bridge on the day it opened, the bridge started to sway from side to side: many pedestrians fell spontaneously into step with the bridge's vibrations, inadvertently amplifying them. Here we model this unexpected and now notorious phenomenon - which was not due to the bridge's innovative design as was first thought - by adapting ideas originally developed to describe the collective synchronization of biological oscillators such as neurons and fireflies. Our approach should help engineers to estimate the damping needed to stabilize other exceptionally crowded footbridges against synchronous lateral excitation by pedestrians.

  4. Theoretical mechanics: crowd synchrony on the Millennium Bridge.

    PubMed

    Strogatz, Steven H; Abrams, Daniel M; McRobie, Allan; Eckhardt, Bruno; Ott, Edward

    2005-11-01

    Soon after the crowd streamed on to London's Millennium Bridge on the day it opened, the bridge started to sway from side to side: many pedestrians fell spontaneously into step with the bridge's vibrations, inadvertently amplifying them. Here we model this unexpected and now notorious phenomenon--which was not due to the bridge's innovative design as was first thought--by adapting ideas originally developed to describe the collective synchronization of biological oscillators such as neurons and fireflies. Our approach should help engineers to estimate the damping needed to stabilize other exceptionally crowded footbridges against synchronous lateral excitation by pedestrians. PMID:16267545

  5. Learning Bridges: A Role for Mobile Technologies in Education

    ERIC Educational Resources Information Center

    Vavoula, Giasemi; Sharples, Mike; Lonsdale, Peter; Rudman, Paul; Meek, Julia

    2007-01-01

    MyArtSpace is a service for children to spread their learning between schools and museums using mobile phones linked to a personal Web space. Using MyArtSpace as an example, the authors discuss the possibilities for mobile technology to form bridges between formal and informal learning. They also offer guidelines for designing such bridges.…

  6. Developmental Summer Bridge Programs. What Works Clearinghouse™ Intervention Report

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2015

    2015-01-01

    Developmental summer bridge programs are designed to reduce the need for developmental education in college by providing students with accelerated instruction in areas where additional knowledge and skills are needed to help them succeed in higher education. The WWC identified one study of developmental summer bridge programs that meets WWC…

  7. 6. VIEW OF BRIDGE COMMEMORATIVE PLAQUE WHICH STATES '1908, J. ...

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

    6. VIEW OF BRIDGE COMMEMORATIVE PLAQUE WHICH STATES '1908, J. H. CROOKS, ED. ELLIS, A. S. LELAND, COMMISSIONERS. L. E. BRELSFORD, AUDITOR. L. WEST, SURVEYOR. - B. C. GERWICK, DESIGNER. F. E. WITHCOTT, ENG. ON CONST. C. A. WARNER, CONTRACTOR.' - First Street Reinforced Concrete Bridge, Spanning Moxahala Creek at First Street (CR 7), Roseville, Muskingum County, OH

  8. Summer Bridge Programs. What Works Clearinghouse Intervention Report

    ERIC Educational Resources Information Center

    What Works Clearinghouse, 2016

    2016-01-01

    "Summer bridge programs" are designed to ease the transition to college and support postsecondary success by providing students with the academic skills and social resources needed to succeed in a college environment. These programs occur in the summer "bridge" period between high school and college. Although the content of…

  9. Truck-based mobile wireless sensor networks for the experimental observation of vehicle-bridge interaction

    NASA Astrophysics Data System (ADS)

    Kim, Junhee; Lynch, Jerome P.; Lee, Jong-Jae; Lee, Chang-Geun

    2011-06-01

    Heavy vehicles driving over a bridge create a complex dynamic phenomenon known as vehicle-bridge interaction. In recent years, interest in vehicle-bridge interaction has grown because a deeper understanding of the phenomena can lead to improvements in bridge design methods while enhancing the accuracy of structural health monitoring techniques. The mobility of wireless sensors can be leveraged to directly monitor the dynamic coupling between the moving vehicle and the bridge. In this study, a mobile wireless sensor network is proposed for installation on a heavy truck to capture the vertical acceleration, horizontal acceleration and gyroscopic pitching of the truck as it crosses a bridge. The vehicle-based wireless monitoring system is designed to interact with a static, permanent wireless monitoring system installed on the bridge. Specifically, the mobile wireless sensors time-synchronize with the bridge's wireless sensors before transferring the vehicle response data. Vertical acceleration and gyroscopic pitching measurements of the vehicle are combined with bridge accelerations to create a time-synchronized vehicle-bridge response dataset. In addition to observing the vehicle vibrations, Kalman filtering is adopted to accurately track the vehicle position using the measured horizontal acceleration of the vehicle and positioning information derived from piezoelectric strip sensors installed on the bridge deck as part of the bridge monitoring system. Using the Geumdang Bridge (Korea), extensive field testing of the proposed vehicle-bridge wireless monitoring system is conducted. Experimental results verify the reliability of the wireless system and the accuracy of the vehicle positioning algorithm.

  10. Instrumentation of bridges for long-term performance monitoring

    NASA Astrophysics Data System (ADS)

    Feng, Maria Q.; Kim, Doo-Kie; Sheng, Li-Hong; Fiji, Leonard M.; Kim, Yoo J.

    2001-08-01

    As the state of the art in bridge design is advancing toward the performance-based design, it becomes increasingly important to monitor and evaluate the long-term structural performance of bridges, including strains in critical structural members, soil pressures on the abutment back walls and footings, accelerations on the decks and bents, etc. Such information is essential in developing new performance criteria for design. In this research, sensor systems for long-term structural performance monitoring have been installed on two new highway bridges on Orange County, California: the Jamboree Road Overcrossing and the West Street On-Ramp.

  11. The Memory Bridge Initiative on Service Learners

    ERIC Educational Resources Information Center

    Wescott, Amy; Healy, Tara C.

    2011-01-01

    This study evaluated the Memory Bridge Initiative (MBI), an educational, experiential program pairing high school students with older adults who have dementia. A qualitative, single group design with baseline and follow-up measures examined whether or not students would have a positive learning experience while gaining newfound appreciation and…

  12. Comparison of aerodynamic characteristics of pentagonal and hexagonal shaped bridge decks

    NASA Astrophysics Data System (ADS)

    Haque, Md. Naimul; Katsuchi, Hiroshi; Yamada, Hitoshi; Nishio, Mayuko

    2016-07-01

    Aerodynamics of the long-span bridge deck should be well understood for an efficient design of the bridge system. For practical bridges various deck shapes are being recommended and adopted, yet not all of their aerodynamic behaviors are well interpreted. In the present study, a numerical investigation was carried out to explore the aerodynamic characteristics of pentagonal and hexagonal shaped bridge decks. A relative comparison of steady state aerodynamic responses was made and the flow field was critically analyzed for better understanding the aerodynamic responses. It was found that the hexagonal shaped bridge deck has better aerodynamic characteristics as compared to the pentagonal shaped bridge deck.

  13. Bridge inspection in Kansas

    NASA Astrophysics Data System (ADS)

    Whisler, Don E.

    1995-05-01

    The purpose of this paper is to give the reader a brief insight into the Kansas Department of Transportation (KDOT) Bridge Inspection Program. The State of Kansas has 25,580 bridge length structures within its boundaries used to carry vehicle traffic or pedestrians, excluding railroad. This total ranks third within the nation according to the November issue of 'Better Roads.' The total number of structures listed includes 20,453 structures owned by local governments, 340 structures owned by the Kansas Turnpike Authority, and 4,787 structures owned by the KDOT. This paper will deal specifically with the KDOT structures only.

  14. 198. SPOUT RUN ARCH BRIDGE AND SPOUT RUN WESTBOUND BRIDGE ...

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

    198. SPOUT RUN ARCH BRIDGE AND SPOUT RUN WESTBOUND BRIDGE FROM POTOMAC RIVER LOOKING SOUTHWEST. - George Washington Memorial Parkway, Along Potomac River from McLean to Mount Vernon, VA, Mount Vernon, Fairfax County, VA

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

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

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

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

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

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

  17. Shoreham Railroad Bridge, Title Sheet Shoreham Railroad Bridge, Former ...

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

    Shoreham Railroad Bridge, Title Sheet - Shoreham Railroad Bridge, Former Addison County Railroad (later, Rutland Railroad, Addison Branch), spanning Lemon Fair River above Richville Pond, west of East Shoreham Road, Shoreham, Addison County, VT

  18. Asymmetrical phase-shifted full-bridge

    SciTech Connect

    Fiedler, A.; Grotstollen, H.

    1995-12-31

    In comparison to forward-converters bridge topologies make use of parasitic components for resonant transition without need of additional clamping circuitry. Thus, they are privileged in building high frequency high power converters, even if high efficiency is required. This paper introduces a new modulation scheme for H-bridges, which combines PWM and phase-modulation. An analysis of the ideal circuit is presented together with design guidelines. Some experimental data for a converter prototype are given for 300V/5V--750W, 250 kHz.

  19. Planar Hall effect bridge magnetic field sensors

    SciTech Connect

    Henriksen, A. D.; Dalslet, B. T.; Skieller, D. H.; Lee, K. H.; Okkels, F.; Hansen, M. F.

    2010-07-05

    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.

  20. Bridge Types: Suspension Bridge Spans, Section AA; Cantilever Truss Spans, ...

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

    Bridge Types: Suspension Bridge Spans, Section A-A; Cantilever Truss Spans, Section B-B; Through Truss Spans, Section C-C; Deck Truss Spans, Section D-D - San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Francisco, San Francisco County, CA

  1. Novel perspectives in bridges inspection using GPR

    NASA Astrophysics Data System (ADS)

    Benedetto, A.; Manacorda, G.; Simi, A.; Tosti, F.

    2012-09-01

    Bridge engineers increasingly prefer to use the Ground-Penetrating Radar (GPR) technique. GPR can yield data with very high spatial resolution, the data can be acquired rapidly and even during traffic, causing very low interferences. This paper presents a novel GPR system that is designed and developed for bridge applications. In addition it proposes a new algorithm for cracks tracking in a three-dimensional domain. The effectiveness and accuracy of the procedure have been calibrated and validated on four different bridges. In this paper, three-dimensional visualisations of cracks and two-dimensional tomographies and sections are shown to demonstrate the potentialities of the GPR system associated to the signal-processing algorithm.

  2. Dynamics and statics of nonaxisymmetric liquid bridges

    NASA Technical Reports Server (NTRS)

    Alexander, J. Iwan D.; Resnick, Andy; Zhang, Yiqiang; Fedoseyev, A.

    1994-01-01

    We finished the construction of the experimental apparatus and the design and testing of some of the visualization and data acquisition techniques. Experimental work focused on three areas: force measurements, loss of stability to nonaxisymmetric bridges, and vibration behavior. The experimental work is summarized in section 2. Selected results from our force measurement experiments are outlined in section 3. In addition we worked on the theory of the dynamic stability of axisymmetric bridges and undertook numerical simulation of the effects of inclined gravity vectors on the minimum volume stability limit for static bridges. The results and status of our theoretical work and numerical simulation are described in section 4. Papers published and in preparation, conference presentations, etc., are described in section 5. Work planned for the third year is discussed in section 6. References cited in the report are listed in section 7.

  3. 21. RAILROAD, RR. BRIDGE MISSISSIPPI, CLAY CO., WAVERLY 1.5 mi. ...

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

    21. RAILROAD, RR. BRIDGE MISSISSIPPI, CLAY CO., WAVERLY 1.5 mi. S of Ms. 50 Proposed 218-foot turn span, design #2339 of Virginia Bridge and Iron Co., Roanoke, Va. 13 May 1914. Act. size: 16x11 in. Credit: Columbus & Greenville RR, Columbus, Ms. Sarcone Photography, Columbus, Ms. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

  4. BUILDING "BRIDGES" WITH QUALITY ASSURANCE

    EPA Science Inventory

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

  5. Quantum Bidding in Bridge

    NASA Astrophysics Data System (ADS)

    Muhammad, Sadiq; Tavakoli, Armin; Kurant, Maciej; Pawłowski, Marcin; Żukowski, Marek; Bourennane, Mohamed

    2014-04-01

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

  6. The Bridge to Somewhere

    ERIC Educational Resources Information Center

    Lum, Lydia

    2009-01-01

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

  7. Bridging the Gap.

    ERIC Educational Resources Information Center

    Kroto, Joseph J.

    1988-01-01

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

  8. Bridging the Abyss

    ERIC Educational Resources Information Center

    Olcott, Marianina

    2007-01-01

    This paper seeks to explain the epistemological bases for the two cultures and to show why this disciplinary divide continues to plague American academic culture. Next, we discuss strategies for bridging the two cultures through general education curricula which promote mutual understanding of the two cultures while educating students in basic…

  9. Building Migratory Bridges

    ERIC Educational Resources Information Center

    Roy, Michael; Doss, Laurie K.

    2007-01-01

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

  10. Bridging Disciplinary Boundaries

    ERIC Educational Resources Information Center

    Mei, Linda

    2009-01-01

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

  11. Bridging the Gaps.

    ERIC Educational Resources Information Center

    Netzer, Greg

    1995-01-01

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

  12. Bridge the Gap.

    ERIC Educational Resources Information Center

    Klein, Mel; Cufaude, Jeffrey B.

    1989-01-01

    This document consists of two paired articles: the first, "Preparing Faculty Out of Class Experiences," by Mel Klein, and the second, "Help Advisers Be More Than Ghost Signatures," by Jeffrey B. Calfaude. Each article shares insights on how faculty advisers "bridge the gap" between students and faculty. When faculty members are asked to advise…

  13. Suspension Bridges: A Merger of Physics, Engineering, and Art

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1974-01-01

    Discusses the physical principles underlying the design of a small scale suspension bridge, including its types and strength calculations. Included are the working equation and two formulas for determining the load per unit length. (CC)

  14. Electrical Actuation Technology Bridging

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

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

  15. Cracking behavior of structural slab bridge decks

    NASA Astrophysics Data System (ADS)

    Baah, Prince

    Bridge deck cracking is a common problem throughout the United States, and it affects the durability and service life of concrete bridges. Several departments of transportation (DOTs) in the United States prefer using continuous three-span solid structural slab bridges without stringers over typical four-lane highways. Recent inspections of such bridges in Ohio revealed cracks as wide as 0.125 in. These measured crack widths are more than ten times the maximum limit recommended in ACI 224R-01 for bridge decks exposed to de-icing salts. Measurements using digital image correlation revealed that the cracks widened under truck loading, and in some cases, the cracks did not fully close after unloading. This dissertation includes details of an experimental investigation of the cracking behavior of structural concrete. Prism tests revealed that the concrete with epoxy-coated bars (ECB) develops the first crack at smaller loads, and develops larger crack widths compared to the corresponding specimens with uncoated (black) bars. Slab tests revealed that the slabs with longitudinal ECB developed first crack at smaller loads, exhibited wider cracks and a larger number of cracks, and failed at smaller ultimate loads compared to the corresponding test slabs with black bars. To develop a preventive measure, slabs with basalt and polypropylene fiber reinforced concrete were also included in the test program. These test slabs exhibited higher cracking loads, smaller crack widths, and higher ultimate loads at failure compared to the corresponding slab specimens without fibers. Merely satisfying the reinforcement spacing requirements given in AASHTO or ACI 318-11 is not adequate to limit cracking below the ACI 224R-01 recommended maximum limit, even though all the relevant design requirements are otherwise met. Addition of fiber to concrete without changing any steel reinforcing details is expected to reduce the severity and extent of cracking in reinforced concrete bridge decks.

  16. Nematic liquid crystal bridges

    NASA Astrophysics Data System (ADS)

    Doss, Susannah; Ellis, Perry; Vallamkondu, Jayalakshmi; Danemiller, Edward; Vernon, Mark; Fernandez-Nieves, Alberto

    We study the effects of confining a nematic liquid crystal between two parallel glass plates with homeotropic boundary conditions for the director at all bounding surfaces. We find that the free surface of the nematic bridge is a surface of constant mean curvature. In addition, by changing the distance between the plates and the contact angle with the glass plates, we transition between loops and hedgehogs that can be either radial or hyperbolic.

  17. On the road to metallic nanoparticles by rational design: bridging the gap between atomic-level theoretical modeling and reality by total scattering experiments

    NASA Astrophysics Data System (ADS)

    Prasai, Binay; Wilson, A. R.; Wiley, B. J.; Ren, Y.; Petkov, Valeri

    2015-10-01

    The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au100-xPdx (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when ``tuned up'' against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design.The extent to which current theoretical modeling alone can

  18. On the road to metallic nanoparticles by rational design: bridging the gap between atomic-level theoretical modeling and reality by total scattering experiments.

    PubMed

    Prasai, Binay; Wilson, A R; Wiley, B J; Ren, Y; Petkov, Valeri

    2015-11-14

    The extent to which current theoretical modeling alone can reveal real-world metallic nanoparticles (NPs) at the atomic level was scrutinized and demonstrated to be insufficient and how it can be improved by using a pragmatic approach involving straightforward experiments is shown. In particular, 4 to 6 nm in size silica supported Au(100-x)Pd(x) (x = 30, 46 and 58) explored for catalytic applications is characterized structurally by total scattering experiments including high-energy synchrotron X-ray diffraction (XRD) coupled to atomic pair distribution function (PDF) analysis. Atomic-level models for the NPs are built by molecular dynamics simulations based on the archetypal for current theoretical modeling Sutton-Chen (SC) method. Models are matched against independent experimental data and are demonstrated to be inaccurate unless their theoretical foundation, i.e. the SC method, is supplemented with basic yet crucial information on the length and strength of metal-to-metal bonds and, when necessary, structural disorder in the actual NPs studied. An atomic PDF-based approach for accessing such information and implementing it in theoretical modeling is put forward. For completeness, the approach is concisely demonstrated on 15 nm in size water-dispersed Au particles explored for bio-medical applications and 16 nm in size hexane-dispersed Fe48Pd52 particles explored for magnetic applications as well. It is argued that when "tuned up" against experiments relevant to metals and alloys confined to nanoscale dimensions, such as total scattering coupled to atomic PDF analysis, rather than by mere intuition and/or against data for the respective solids, atomic-level theoretical modeling can provide a sound understanding of the synthesis-structure-property relationships in real-world metallic NPs. Ultimately this can help advance nanoscience and technology a step closer to producing metallic NPs by rational design. PMID:26463562

  19. Bridge monitoring using heterogeneous wireless sensor network

    NASA Astrophysics Data System (ADS)

    Haran, Shivan; Kher, Shubhalaxmi; Mehndiratta, Vandana

    2010-03-01

    Wireless sensor networks (WSN) are proving to be a good fit where real time monitoring of multiple physical parameters is required. In many applications such as structural health monitoring, patient data monitoring, traffic accident monitoring and analysis, sensor networks may involve interface with conventional P2P systems and it is challenging to handle heterogeneous network systems. Heterogeneous deployments will become increasingly prevalent as it allows for systems to seamlessly integrate and interoperate especially when it comes to applications involving monitoring of large infrastructures. Such networks may have wireless sensor network overlaid on a conventional computer network to pick up data from one distant location and carry out the analysis after relaying it over to another distant location. This paper discusses monitoring of bridges using WSN. As a test bed, a heterogeneous network of WSN and conventional P2P together with a combination of sensing devices (including vibration and strain) is to be used on a bridge model. Issues related to condition assessment of the bridge for situations including faults, overloads, etc., as well as analysis of network and system performance will be discussed. When conducted under controlled conditions, this is an important step towards fine tuning the monitoring system for recommendation of permanent mounting of sensors and collecting data that can help in the development of new methods for inspection and evaluation of bridges. The proposed model, design, and issues therein will be discussed, along with its implementation and results.

  20. Characterization and electrical modeling of semiconductors bridges

    SciTech Connect

    Marx, K.D.; Bickes, R.W. Jr.; Wackerbarth, D.E.

    1997-03-01

    Semiconductor bridges (SCBs) are finding increased use as initiators for explosive and pyrotechnic devices. They offer advantages in reduced voltage and energy requirements, coupled with excellent safety features. The design of explosive systems which implement either SCBs or metal bridgewires can be facilitated through the use of electrical simulation software such as the PSpice{reg_sign} computer code. A key component in the electrical simulation of such systems is an electrical model of the bridge. This report has two objectives: (1) to present and characterize electrical data taken in tests of detonators which employ SCBs with BNCP as the explosive powder; and (2) to derive appropriate electrical models for such detonators. The basis of such models is a description of the resistance as a function of energy deposited in the SCB. However, two important features which must be added to this are (1) the inclusion of energy loss through such mechanisms as ohmic heating of the aluminum lands and heat transfer from the bridge to the surrounding media; and (2) accounting for energy deposited in the SCB through heat transfer to the bridge from the explosive powder after the powder ignites. The modeling procedure is entirely empirical; i.e., models for the SCB resistance and the energy gain and loss have been estimated from experimental data taken over a range of firing conditions. We present results obtained by applying the model to the simulation of SCB operation in representative tests.

  1. Bridging the Gap.

    PubMed

    Webb, Michele

    2016-01-01

    The view from the top of Hoover Dam looking south over the Colorado River was breathtaking! My friend and I stood there in silence, taking it all in. I had visited Hoover Dam on many occasions, but this visit was the first time I had seen the arch bridge that carries US Route 93 over the river and joins Nevada and Arizona states. It was a beautiful day, the temperature was perfect, and there was a slight breeze coming from Lake Mead behind us as we took in the view. PMID:27556855

  2. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

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

  3. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

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

  4. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

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

  5. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

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

  6. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

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

  7. Translating Climate Projections for Bridge Engineering

    NASA Astrophysics Data System (ADS)

    Anderson, C.; Takle, E. S.; Krajewski, W.; Mantilla, R.; Quintero, F.

    2015-12-01

    A bridge vulnerability pilot study was conducted by Iowa Department of Transportation (IADOT) as one of nineteen pilots supported by the Federal Highway Administration Climate Change Resilience Pilots. Our pilot study team consisted of the IADOT senior bridge engineer who is the preliminary design section leader as well as climate and hydrological scientists. The pilot project culminated in a visual graphic designed by the bridge engineer (Figure 1), and an evaluation framework for bridge engineering design. The framework has four stages. The first two stages evaluate the spatial and temporal resolution needed in climate projection data in order to be suitable for input to a hydrology model. The framework separates streamflow simulation error into errors from the streamflow model and from the coarseness of input weather data series. In the final two stages, the framework evaluates credibility of climate projection streamflow simulations. Using an empirically downscaled data set, projection streamflow is generated. Error is computed in two time frames: the training period of the empirical downscaling methodology, and an out-of-sample period. If large errors in projection streamflow were observed during the training period, it would indicate low accuracy and, therefore, low credibility. If large errors in streamflow were observed during the out-of-sample period, it would mean the approach may not include some causes of change and, therefore, the climate projections would have limited credibility for setting expectations for changes. We address uncertainty with confidence intervals on quantiles of streamflow discharge. The results show the 95% confidence intervals have significant overlap. Nevertheless, the use of confidence intervals enabled engineering judgement. In our discussions, we noted the consistency in direction of change across basins, though the flood mechanism was different across basins, and the high bound of bridge lifetime period quantiles exceeded

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

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

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

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

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

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

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

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

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

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

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

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

  12. 47 CFR 80.1007 - Bridge-to-bridge radiotelephone installation.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

  13. Integrated giant magnetoresistance bridge sensors with transverse permanent magnet biasing

    NASA Astrophysics Data System (ADS)

    Ku, Wanjun; Silva, F.; Bernardo, J.; Freitas, P. P.

    2000-05-01

    Two types of giant magnetoresistance (GMR) multilayer bridge sensors with integrated permanent magnet biasing are demonstrated. These sensors differ from previous designs where external permanent magnets were used. The bridges consist of four active GMR multilayer elements at the first antiferromagnetic coupling peak of a NiFe/[NiFe/CoFe/Cu]10 structure (GMR=18%). Bridge linearization is obtained by creating opposite biasing fields of equal amplitude (±200 Oe) in contiguous GMR elements of the bridge structure. This is achieved either by using pairs of permanent magnets with the same Mrt value (14 memu/cm2) but different coercivities (type I bridge, Hc1=1400 Oe, Hc2=800 Oe), or by using a single type of permanent magnet and placing the GMR sensor either under the magnet, or on its side (type II bridge). Linear ranges of ±200 Oe with field sensitivities of 0.3 mV/(V×Oe) were obtained in these bridges.

  14. Expected damages of retrofitted bridges with RC jacketing

    NASA Astrophysics Data System (ADS)

    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.

  15. The violin bridge as filter.

    PubMed

    Bissinger, George

    2006-07-01

    The violin bridge filter role was investigated using modal and acoustic measurements on 12 quality-rated violins combined with systematic bridge rocking frequency f(rock) and wing mass decrements deltam on four bridges for two other violins. No isolated bridge resonances were observed; bridge motions were complex (including a "squat" mode near 0.8 kHz) except for low frequency rigid body pivot motions, all more or less resembling rocking motion at higher frequencies. A conspicuous broad peak near 2.3 kHz in bridge driving point mobility (labeled BH) was seen for good and bad violins. Similar structure was seen in averaged bridge, bridge feet, corpus mobilities and averaged radiativity. No correlation between violin quality and BH driving point, averaged corpus mobility magnitude, or radiativity was found. Increasing averaged-over-f(rock) deltam(g) from 0 to 0.12 generally increased radiativity across the spectrum. Decreasing averaged-over-deltam f(rock) from 3.6 to 2.6 kHz produced consistent decreases in radiativity between 3 and 4.2 kHz, but only few-percent decreases in BH frequency. The lowest f(rock) values were accompanied by significantly reduced radiation from the Helmholtz A0 mode near 280 Hz; this, combined with reduced high frequency output, created overall radiativity profiles quite similar to "bad" violins among the quality-rated violins. PMID:16875244

  16. Identification of damping in a bridge using a moving instrumented vehicle

    NASA Astrophysics Data System (ADS)

    González, A.; OBrien, E. J.; McGetrick, P. J.

    2012-08-01

    In recent years, there has been a significant increase in the number of bridges which are being instrumented and monitored on an ongoing basis. This is in part due to the introduction of bridge management systems designed to provide a high level of protection to the public and early warning if the bridge becomes unsafe. This paper investigates a novel alternative; a low-cost method consisting of the use of a vehicle fitted with accelerometers on its axles to monitor the dynamic behaviour of bridges. A simplified half-car vehicle-bridge interaction model is used in theoretical simulations to test the effectiveness of the approach in identifying the damping ratio of the bridge. The method is tested for a range of bridge spans and vehicle velocities using theoretical simulations and the influences of road roughness, initial vibratory condition of the vehicle, signal noise, modelling errors and frequency matching on the accuracy of the results are investigated.

  17. Cost of Impressed Current Cathodic Protection for Coastal Oregon Bridges

    SciTech Connect

    Holcomb, Gordon R.; Cryer, Curtis B.

    1998-07-01

    The State of Oregon is using arc-sprayed zinc coatings for anodes in impressed current cathodic protection (ICCP) systems on reinforced concrete coastal bridges. The two lowest bids for four ICCP projects were averaged and converted to 1997 dollars. The total average cost for the ICCP projects was $51.63/ft2 ($555.51/m2) of protected concrete. The cathodic protection part of the ICCP projects average $14.08/ft2 ($151.47/m2), while zinc anode installation cost an average of $7.13/ft2 ($76.67/m2). Oregon's rugged and beautiful coastline is graced with a series of historical arched bridges designed by Conde B. McCullough. McCullough is the internationally recognized architect who designed many of the Oregon Coast Highway (U.S. 101) bridges in the 1920s and 1930s. Many are listed on the National Historic Register. After the expense ($45m) and public outcry associated with the replacement of the historic Alsea Bay Bridge in Waldport, Oregon, the Oregon Department of Transportation began using impressed current cathodic protection (ICCP) to extend the service life of reinforced concrete bridges. Figure 1 visually illustrates the need for such remediation. It shows exposed rebar from underneath the Brush Creek Bridge, which is very representative of the conditions found underneath many coastal Oregon bridges. Four ICCP projects have been funded, put out for bid, and completed. The four projects, their bid closing dates, and their completion dates are the Cape Creek Bridge (1990- 1992), the Yaquina Bay Bridge south arches (1991-1995), the Depoe Bay Bridge (1993-1997), and the Yaquina Bay Bridge south approach (1995-1997). The Cape Creek, Yaquina Bay, and Depoe Bay Bridges are shown in Figs. 2-4. Other ICCP projects are underway on the Oregon coast. In the ICCP systems, arc-sprayed zinc coatings on the concrete surface are anodes that protect the steel rebar. Accelerated laboratory studies at the Albany Research Center have predicted zinc anode service lives of

  18. Burning trees and bridges

    NASA Technical Reports Server (NTRS)

    Levine, Joel S.

    1990-01-01

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

  19. Online bridge crack monitoring with smart film.

    PubMed

    Zhang, Benniu; Wang, Shuliang; Li, Xingxing; Zhou, Zhixiang; Zhang, Xu; Yang, Guang; Qiu, Minfeng

    2013-01-01

    Smart film crack monitoring method, which can be used for detecting initiation, length, width, shape, location, and propagation of cracks on real bridges, is proposed. Firstly, the fabrication of the smart film is developed. Then the feasibility of the method is analyzed and verified by the mechanical sensing character of the smart film under the two conditions of normal strain and crack initiation. Meanwhile, the coupling interference between parallel enameled wires of the smart film is discussed, and then low-frequency detecting signal and the custom communication protocol are used to decrease interference. On this basis, crack monitoring system with smart film is designed, where the collected crack data is sent to the remote monitoring center and the cracks are simulated and recurred. Finally, the monitoring system is applied to six bridges, and the effects are discussed. PMID:24489496

  20. Online Bridge Crack Monitoring with Smart Film

    PubMed Central

    Wang, Shuliang; Li, Xingxing; Zhou, Zhixiang; Zhang, Xu; Yang, Guang; Qiu, Minfeng

    2013-01-01

    Smart film crack monitoring method, which can be used for detecting initiation, length, width, shape, location, and propagation of cracks on real bridges, is proposed. Firstly, the fabrication of the smart film is developed. Then the feasibility of the method is analyzed and verified by the mechanical sensing character of the smart film under the two conditions of normal strain and crack initiation. Meanwhile, the coupling interference between parallel enameled wires of the smart film is discussed, and then low-frequency detecting signal and the custom communication protocol are used to decrease interference. On this basis, crack monitoring system with smart film is designed, where the collected crack data is sent to the remote monitoring center and the cracks are simulated and recurred. Finally, the monitoring system is applied to six bridges, and the effects are discussed. PMID:24489496

  1. Cascaded resonant bridge converters

    NASA Technical Reports Server (NTRS)

    Stuart, Thomas A. (Inventor)

    1989-01-01

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

  2. Instrumentation for detailed bridge-scour measurements

    USGS Publications Warehouse

    Landers, Mark N.; Mueller, David S.; Trent, Roy E.

    1993-01-01

    A portable instrumentation system is being developed to obtain channel bathymetry during floods for detailed bridge-scour measurements. Portable scour measuring systems have four components: sounding instrument, horizontal positioning instrument, deployment mechanisms, and data storage device. The sounding instrument will be a digital fathometer. Horizontal position will be measured using a range-azimuth based hydrographic survey system. The deployment mechanism designed for this system is a remote-controlled boat using a small waterplane area, twin-hull design. An on-board computer and radio will monitor the vessel instrumentation, record measured data, and telemeter data to shore.

  3. Nanoparticle bridge DNA biosensor

    NASA Astrophysics Data System (ADS)

    Huang, Hong-Wen

    A new DNA sensing method is demonstrated in which DNA hybridization events lead to the formation of nanoparticle satellites that bridge two electrodes and are detected electrically. The hybridization events are exclusively carried out only on specific locations, the surfaces of C-ssDNA modified 50 nm GNPs. The uniqueness of this work is that only a small number of T-ccDNA molecules (<10) is required to form the nanoparticle satellites, allowing ultra-sensitive DNA sensing. The principle of this new DNA sensing technique has been demonstrated using target DNA and three-base-pair-mismatched DNA in 20nM concentrations. Three single-stranded DNA (ssDNA) system is used in our experiment which includes Capture-ssDNA (C-ssDNA), Target-ssDNA (T-ssDNA) and Probe-ssDNA (P-ssDNA). Both C-ssDNA and P-ssDNA are modified by a thiol group and can hybridize with different portions of T-ssDNA. T-ssDNA requires no modification in three ssDNA system, which is beneficial in many applications. C-ssDNA modified 50nm gold nanoparticle (C-50au) and P-ssDNA modified 30nm gold nanoparticle (P-30au) are prepared through the reaction of thiol-gold chemical bonding between thiolated ssDNA and gold nanoparticle (GNP) (C-ssDNA with 50nm GNP, P-ssDNA with 30nm GNP). We controllably place the C-50au only on the SiO2 band surface (˜ 90nm width) between two gold electrodes (source and drain electrodes) by forming positively- and negatively-charged self-assembled monolayers (SAMs) on SiO2 and gold surface, respectively. DNA modified GNP is negatively charged due to ionization of phosphate group on DNA back bone. C-50au therefore is negatively charged and can only be attracted toward SiO2 area (repelled by negatively charged gold electrode surface). The amine group of positively-charged SAMs on SiO2 surface is then passivated by converting to non-polar methyl functional group after C-50au placement. P-30au is first hybridized with T-ssDNA in the solution phase (T-P- 30au formed) and is introduced

  4. Bridge SHM system based on fiber optical sensing technology

    NASA Astrophysics Data System (ADS)

    Li, Sheng; Fan, Dian; Fu, Jiang-hua; Huang, Xing; Jiang, De-sheng

    2015-09-01

    The latest progress of our lab in recent 10 years on the area of bridge structural health monitoring (SHM) based on optical fiber sensing technology is introduced. Firstly, in the part of sensing technology, optical fiber force test-ring, optical fiber vibration sensor, optical fiber smart cable, optical fiber prestressing loss monitoring method and optical fiber continuous curve mode inspection system are developed, which not only rich the sensor types, but also provides new monitoring means that are needed for the bridge health monitoring system. Secondly, in the optical fiber sensing network and computer system platform, the monitoring system architecture model is designed to effectively meet the integration scale and effect requirement of engineering application, especially the bridge expert system proposed integration of sensing information and informatization manual inspection to realize the mode of multi index intelligence and practical monitoring, diagnosis and evaluation. Finally, the Jingyue bridge monitoring system as the representative, the research on the technology of engineering applications are given.

  5. The Learning Research Cycle: Bridging Research and Practice

    NASA Astrophysics Data System (ADS)

    Stuessy, Carol L.; Metty, Jane S.

    2007-10-01

    A science teacher and her mentor reflect on their participation in the Learning Research Cycle, a professional learning model that bridges research and practice in both university and public school contexts. Teachers do scientific research in scientists’ laboratories, then bridge their scientific experiences with the design of new classroom learning environments and teacher-driven educational research projects. Science students do scientific research via their teachers’ lessons that bridge laboratory research with classroom learning. Scientists and educational researchers bridge their research interests to create new questions centered on teaching and learning in authentic science learning environments. The authors engaged in this qualitative inquiry present their perspectives on “what goes on,” “what we have learned,” and “what it means to the larger community.”

  6. Venture Creation Programs: Bridging Entrepreneurship Education and Technology Transfer

    ERIC Educational Resources Information Center

    Lackéus, Martin; Williams Middleton, Karen

    2015-01-01

    Purpose: The purpose of this paper is to explore how university-based entrepreneurship programs, incorporating real-life venture creation into educational design and delivery, can bridge the gap between entrepreneurship education and technology transfer within the university environment. Design/methodology/approach: Based on a literature review…

  7. Acquisition and Analysis of Dynamic Responses of a Historic Pedestrian Bridge using Video Image Processing

    NASA Astrophysics Data System (ADS)

    O'Byrne, Michael; Ghosh, Bidisha; Schoefs, Franck; O'Donnell, Deirdre; Wright, Robert; Pakrashi, Vikram

    2015-07-01

    Video based tracking is capable of analysing bridge vibrations that are characterised by large amplitudes and low frequencies. This paper presents the use of video images and associated image processing techniques to obtain the dynamic response of a pedestrian suspension bridge in Cork, Ireland. This historic structure is one of the four suspension bridges in Ireland and is notable for its dynamic nature. A video camera is mounted on the river-bank and the dynamic responses of the bridge have been measured from the video images. The dynamic response is assessed without the need of a reflector on the bridge and in the presence of various forms of luminous complexities in the video image scenes. Vertical deformations of the bridge were measured in this regard. The video image tracking for the measurement of dynamic responses of the bridge were based on correlating patches in time-lagged scenes in video images and utilisinga zero mean normalised cross correlation (ZNCC) metric. The bridge was excited by designed pedestrian movement and by individual cyclists traversing the bridge. The time series data of dynamic displacement responses of the bridge were analysedto obtain the frequency domain response. Frequencies obtained from video analysis were checked against accelerometer data from the bridge obtained while carrying out the same set of experiments used for video image based recognition.

  8. Acquisition and Analysis of Dynamic Responses of a Historic Pedestrian Bridge using Video Image Processing

    NASA Astrophysics Data System (ADS)

    O'Byrne, Michael; Ghosh, Bidisha; Schoefs, Franck; O'Donnell, Deirdre; Wright, Robert; Pakrashi, Vikram

    2015-07-01

    Video based tracking is capable of analysing bridge vibrations that are characterised by large amplitudes and low frequencies. This paper presents the use of video images and associated image processing techniques to obtain the dynamic response of a pedestrian suspension bridge in Cork, Ireland. This historic structure is one of the four suspension bridges in Ireland and is notable for its dynamic nature. A video camera is mounted on the river-bank and the dynamic responses of the bridge have been measured from the video images. The dynamic response is assessed without the need of a reflector on the bridge and in the presence of various forms of luminous complexities in the video image scenes. Vertical deformations of the bridge were measured in this regard. The video image tracking for the measurement of dynamic responses of the bridge were based on correlating patches in time-lagged scenes in video images and utilisinga zero mean normalisedcross correlation (ZNCC) metric. The bridge was excited by designed pedestrian movement and by individual cyclists traversing the bridge. The time series data of dynamic displacement responses of the bridge were analysedto obtain the frequency domain response. Frequencies obtained from video analysis were checked against accelerometer data from the bridge obtained while carrying out the same set of experiments used for video image based recognition.

  9. Liquid-Bridge Breaking Limits

    NASA Astrophysics Data System (ADS)

    Macner, Ashley; Steen, Paul

    2011-11-01

    Wet adhesion by liquid bridges in large arrays shows promise for use in lightweight, controllable on-demand devices. Applications include grab/release of wafer substrates, transport of micron-sized tiles for use in 3D printing and micro-dosing of personalized pharmaceutical drugs. By wetting and spreading, a drop can form a bridge and thereby ``grab'' a nearby solid substrate. By volume decrease or extension, the bridge can break. The breaking limit corresponds to bridge instability which can be predicted, knowing the static mechanical response of the bridge. Mechanical behaviors include force-volume (FV), pressure-volume (pV) and force-length (FL) responses. Instability crucially depends on the mode of failure - failure under constant-force or constant length are typical cases. We study single bridge equilibria for their breaking limits. FV diagrams for the pin-pin equal and pin-pin unequal radii boundary conditions for different bridge heights are measured in the laboratory. The FL response in the case of pin-pin equal radii is also measured. Results are compared to predictions of static theory. Static results are then used to compare to dynamical sequences where volume is driven quasistatically by syringe or an electro-osmotic pump. As the breaking limit is approached, the shape deformation accelerates leading to non-equilibrium shapes not captured by the static analysis.

  10. Real-time seismic monitoring of the integrated cape girardeau bridge array and recorded earthquake response

    USGS Publications Warehouse

    Celebi, M.

    2006-01-01

    This paper introduces the state of the art, real-time and broad-band seismic monitoring network implemented for the 1206 m [3956 ft] long, cable-stayed Bill Emerson Memorial Bridge in Cape Girardeau (MO), a new Mississippi River crossing, approximately 80 km from the epicentral region of the 1811-1812 New Madrid earthquakes. The bridge was designed for a strong earthquake (magnitude 7.5 or greater) during the design life of the bridge. The monitoring network comprises a total of 84 channels of accelerometers deployed on the superstructure, pier foundations and at surface and downhole free-field arrays of the bridge. The paper also presents the high quality response data obtained from the network. Such data is aimed to be used by the owner, researchers and engineers to assess the performance of the bridge, to check design parameters, including the comparison of dynamic characteristics with actual response, and to better design future similar bridges. Preliminary analyses of ambient and low amplitude small earthquake data reveal specific response characteristics of the bridge and the free-field. There is evidence of coherent tower, cable, deck interaction that sometimes results in amplified ambient motions. Motions at the lowest tri-axial downhole accelerometers on both MO and IL sides are practically free from any feedback from the bridge. Motions at the mid-level and surface downhole accelerometers are influenced significantly by feedback due to amplified ambient motions of the bridge. Copyright ASCE 2006.