WorldWideScience

Sample records for bridges and culverts

  1. Road Bridges and Culverts, Road Culvert Inventory, Published in 2007, Tippecanoe County Government.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset, was produced all or in part from Field Observation information as of 2007. It is described as 'Road Culvert Inventory'. Data...

  2. Wildlife use of existing culverts and bridges in North Central Pennsylvania

    OpenAIRE

    Brudin, Carl O. III

    2003-01-01

    The Pennsylvania Department of Transportation (PENNDOT) District 3-0 initiated a study in North Central Pennsylvania evaluating existing bridges and culverts for use as underpasses by wildlife. This project was a two-phase study to investigate animal passage through existing drainage box culverts, arch culverts and bridges on existing highway systems. The objective of this study was to (1) determine whether wildlife are using existing structures as passageways based on wildlife sign and remot...

  3. Road Bridges and Culverts, Bridges layers located in GIS and Transportation database., Published in unknown, City of Roswell, GA.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset as of unknown. It is described as 'Bridges layers located in GIS and Transportation database.'. Data by this publisher are...

  4. Road Bridges and Culverts, 2006 2' contours; autocad dwg, Published in unknown, Washoe County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset as of unknown. It is described as '2006 2' contours; autocad dwg'. Data by this publisher are often provided in State Plane...

  5. Road Bridges and Culverts, Bridges, Published in 2006, 1:24000 (1in=2000ft) scale, Lafayette County Land Records.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Survey/GPS information as of 2006. It is...

  6. Road Bridges and Culverts, Highway Culverts, Published in 2006, 1:24000 (1in=2000ft) scale, Lafayette County Land Records.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Survey/GPS information as of 2006. It is...

  7. Road Bridges and Culverts, Published in 2005, 1:1200 (1in=100ft) scale, Brown County, WI.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Orthoimagery information as of 2005. Data by this...

  8. Road Bridges and Culverts, Road Bridges point, lines, polygons in Iredell County, NC, Published in 2005, 1:2400 (1in=200ft) scale, Iredell County GIS.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Orthoimagery information as of 2005. It is described...

  9. Road Bridges and Culverts, Bridges inspected by the Manitowoc County Highway Department., Published in 2012, 1:2400 (1in=200ft) scale, Manitowoc County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Orthoimagery information as of 2012. It is described...

  10. Road Bridges and Culverts, Bridge Centerlines for MGRC Service Area, Published in 2007, 1:4800 (1in=400ft) scale, Middle Georgia RC.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Other information as of 2007. It is described as...

  11. Road Bridges and Culverts, 2006 2' contours; autocad dwg, bridge layer, Published in 2006, 1:1200 (1in=100ft) scale, Washoe County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Orthoimagery information as of 2006. It is described...

  12. Railroad Bridges and Culverts, MGRC Service Region, Published in 2007, 1:4800 (1in=400ft) scale, Middle Georgia RC.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Railroad Bridges and Culverts dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Other information as of 2007. It is described as...

  13. Road Bridges and Culverts, All system and non-system bridges in Dickinson County along with sufficiency ratings, Published in 2007, 1:2400 (1in=200ft) scale, Dickinson County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Published Reports/Deeds information as of 2007. It...

  14. Road Bridges and Culverts, Bridges linework as developed during 1996 planimetric and orthoimagery project., Published in 1996, 1:600 (1in=50ft) scale, Vilas County Land Information/Mapping.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Road Bridges and Culverts dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from Orthoimagery information as of 1996. It is described...

  15. Construction safety management of bridge and culvert on railway operation line%铁路营业线桥涵施工安全管理

    Institute of Scientific and Technical Information of China (English)

    姚广恒

    2012-01-01

    对铁路营业线桥涵施工安全管理中应该注意的问题进行了分析,从三方面进行了论述,解决了下穿与上跨铁路营业线施工中常见安全问题,达到了铁路营业线安全运输,桥涵施工安全进行的效果。%This paper discusses matters needing attention in construction safety management of bridge and culvert on railway operation line from three aspects,solves common construction security problems on under crossing and overpassing railway operation line,and achieves safe transportation of railway operation line and safe construction effect of bridge and culvert.

  16. Outside Operation Survey Points of Expressway Reconstruction and Extension Bridge Culvert%高速公路改扩建桥涵外业勘察要点

    Institute of Scientific and Technical Information of China (English)

    郭鑫

    2012-01-01

    结合沈铁高速公路的特点,着重介绍了桥涵外业勘察的重点内容,为高速公路的改扩建设计提供有利的设计依据。%Combined with the features of Shentie Expressway,the key contents of outside operation survey of bridge culvert is introduced emphatically,providing advantageous design basis for expressway reconstruction and extension design.

  17. Research on the small bridge and culvert foundation in permafrost regions of Hulunbuir%呼伦贝尔市永冻土地区小桥涵基础研究

    Institute of Scientific and Technical Information of China (English)

    周成龙; 焦同战

    2012-01-01

    On the basis of mastering the information of hydrology,geology,weather and so on accurately,simulating the temperature-field by integrating the basic theory of engineering cryopedology,land hydrology,groundwater dynamics and thermodynamics,and through the typicality experimental study,the rules and methods of the construction of the highway bridges and culverts in seasonal frozen earth regions are summarized,which can guide the construction of the small bridge and culvert in the frozen earth area such as Hulunbuir and provide theoretical basis to the construction of highway,railway,bridge and culvert foundation and building foundation.%在准确掌握冻土区水文、地质、气象等资料的基础上,综合工程冻土学、陆地水文学、地下水动力学、热力学的基础理论进行温度场数值模拟,并通过典型性试验研究,总结出在季冻土地区进行公路桥涵建设的规律和方法,为在呼伦贝尔及类似冻土地区进行小桥涵施工提供指导,并进一步为在高寒地区公路、铁路桥涵基础、房屋建筑基础提供理论依据。

  18. Fuzzy Comprehensive Evaluation of the Safety of Bridge and Culvert Jacking Construction under the Existing Railway%铁路既有线下桥涵顶进施工安全的模糊综合评价

    Institute of Scientific and Technical Information of China (English)

    杨珍; 樊艳艳; 刘子铭

    2014-01-01

    铁路既有线下桥涵顶进工程对安全的要求很高。本文采用模糊综合评判的方法对施工现场进行评价,对于确保安全施工具有重要意义。%The bridge and culvert jacking engineering under the existing railway lines has a high requirement on the safety. This article uses fuzzy comprehensive evaluation method to evaluate the construction site, which has great significance for ensuring construction safety.

  19. 神华巴准铁路桥涵工程关键管理技术%Key Techniques for Management of Bridge and Culvert Projects of Batuta-Zhungeer Railway,Shenhua Group

    Institute of Scientific and Technical Information of China (English)

    张涛

    2015-01-01

    神华巴准铁路桥涵工程体量庞大,技术标准要求高,沿线地形和工程地质情况复杂多变,冬季严寒漫长,桥涵工程施工和管理难度大。项目建设中以设计、施工、安全和质量管理为抓手,做好特殊地区桥涵的设计深度,严格执行施工组织设计,优化设计变更;加强对上跨既有铁路施工、高墩施工、旧桥基础防冲刷处理、风沙地区桩基施工以及T 梁预制和架设等重点工程的技术管理工作;严格执行《本质安全管理体系》,加强临近既有线、U 形谷斜坡桩基施工的安全管理工作;率先引入第三方检测制度,在桥梁施工、混凝土材料以及 T 梁生产中积极引入新技术、新工艺、新材料及新设备,多种手段加强工程质量控制。目前,巴准铁路已开通试运营。%The construction and management of the bridge and culvert projects of Batuta‐Zhun‐geer Railway ,Shenhua Group are challenging since the proportions of the bridges and culverts ac‐counting for the whole railway are high ,the technical standards set for the projects are demanding , the topographic and geological conditions along the railway are complicated and variable and the winter seasons in the area where the railway is located are severely cold and long .In the construc‐tion of the projects ,the design ,construction ,safety and quality management was taken as the im‐portant starting point ,the proper depth of the design of the bridges and culverts in the special area was required to be achieved ,the construction organization design was required to be strictly imple‐mented and the design variations were required to be optimized wherever necessary .The technical management of the critical works ,such as the construction of the bridges spanning the existing railways and the high‐rise piers ,the scouring protection treatment of the old bridge foundations , the construction of the pile foundations in the

  20. 30t轴重下朔黄铁路桥涵结构强化技术试验研究%Experimental Study on Strengthening Method of Bridges and Culverts under 3 0 t Axle Load in Shuo-huang Railway

    Institute of Scientific and Technical Information of China (English)

    薛继连

    2015-01-01

    通过调研朔黄铁路桥涵结构的运营现状,分析30 t轴重货物列车运营条件下各种跨度桥梁运营活载效应与设计活载效应比值,提出朔黄铁路大轴重重载运输强化改造设计活载图式,开展朔黄铁路30 t 轴重货车实车综合试验,根据各类桥涵结构特点和试验结果,得出大轴重重载列车对桥涵结构的作用规律。从钢筋混凝土简支梁、普通高度预应力混凝土梁、低高度及超低高度预应力混凝土梁、桥梁支座、钢筋混凝土涵洞及框构桥和墩台基础等方面,分析了大轴重重载运输条件下桥涵结构面临的主要技术问题,研发了预应力碳纤维板强化、辅助梁强化、小跨度桥涵强化等技术,研制了新型重载支座。各强化技术与措施经朔黄铁路工程实施与强化效果验证,可提高桥涵结构承载能力,能满足30 t轴重货车运营要求。%Based on the investigation of the current operational state of bridges and culverts along the Shuo-Huang Railway,an analysis was performed on the ratio of the actual and designed live load effects on the bridg-es under the actual 30 t axle load of the freight train.The precept of the strengthening and the reconstruction of the bridges loaded under the heavy axle load was proposed.Based on a comprehensive test and the characteris-tics of the structures of the bridges and culverts,the effect of the 30 t axle load of the freight on bridges and culverts of various spans was studied.The main technical problems faced by bridge and culvert structures under the heavy haul transportation condition were analyzed in terms of reinforced concrete simply-supported girder, prestressed concrete girder with normal height,prestressed concrete shallow girder,bridge bearing,reinforced concrete culvert,framed bridge,and footing of abutment and pier.The challenge of the heavy axle load to the current bridges and culverts at service required strengthening with the

  1. The effects of water flow and temperature on thermal regime around a culvert built on permafrost

    Institute of Scientific and Technical Information of China (English)

    Loriane Prier; Guy Dor; CR Burn

    2014-01-01

    Temperature and water flow through a culvert beneath the Alaska Highway near Beaver Creek, Yukon, were measured at hourly intervals between June and October 2013. These data were used to simulate the effect of the culvert on the thermal regime of the road embankment and subjacent permafrost. A 2-D thermal model of the embankment and permafrost was developed with TEMP/W and calibrated using field observations. Empirical relations were obtained between water tem-peratures at the entrance to the culvert, flow into the culvert, and water temperatures inside the structure. Water temper-atures at the entrance and inside the culvert had a linear relation, while water temperatures inside the culvert and water flow were associated by a logarithmic relation. A multiple linear regression was used to summarize these relations. From this relationship, changes in the flow rate and water temperatures at the entrance of the culvert were simulated to obtain pre-dicted water temperatures in the culvert. The temperatures in the culvert were used in the thermal model to determine their effects on the ground thermal regime near the culvert. Variation of ±10%in water flow rate had no impact on the thermal regime underneath the culvert. Variation of water temperature at the entrance of the culvert had a noticeable influence on the thermal regime. A final simulation was conducted without insulation beneath the culvert. The thaw depth was 30 cm with insulation, and 120 cm without insulation, illustrating the importance of insulation to the ground thermal regime.

  2. Turtles and culverts, and alternative energy development: an unreported but potentially significant mortality threat to the desert tortoise (Gopherus agassizii)

    Science.gov (United States)

    Lovich, J.E.; Ennen, J.R.; Madrak, S.; Grover, B.

    2011-01-01

    Culverts are often used to increase the permeability of roaded landscapes for wildlife, including turtles. Although the benefits of culverts as safe passages for turtles are well documented, under some conditions culverts can entrap them and cause mortality. Here we report a culvert-related mortality in the federally threatened desert tortoise (Gopherus agassizii) at a wind energy facility in California and offer simple recommendations to mitigate the negative effects of culverts for wildlife in general.

  3. Full Scale Tests and Structural Evaluation of Soil-Steel Flexible Culverts for High-Speed Railways

    OpenAIRE

    Andersson, Andreas; Sundquist, Håkan; Karoumi, Raid

    2012-01-01

    In this paper, results from full-scale tests on a corrugated soil-steel flexible culvert for railway traffic are presented. The bridge was instrumented with strain gauges, accelerometers and displacement gauges, measuring the response from passing trains. The aim of the measurement campaign was to gain knowledge of the dynamic behaviour due to train induced vibrations, both of the bridge structure and the overlying railway embankment. From the measured data, the load distribution and soil-sti...

  4. Culvert Analysis Program Graphical User Interface 1.0--A preprocessing and postprocessing tool for estimating flow through culvert

    Science.gov (United States)

    Bradley, D. Nathan

    2013-01-01

    The peak discharge of a flood can be estimated from the elevation of high-water marks near the inlet and outlet of a culvert after the flood has occurred. This type of discharge estimate is called an “indirect measurement” because it relies on evidence left behind by the flood, such as high-water marks on trees or buildings. When combined with the cross-sectional geometry of the channel upstream from the culvert and the culvert size, shape, roughness, and orientation, the high-water marks define a water-surface profile that can be used to estimate the peak discharge by using the methods described by Bodhaine (1968). This type of measurement is in contrast to a “direct” measurement of discharge made during the flood where cross-sectional area is measured and a current meter or acoustic equipment is used to measure the water velocity. When a direct discharge measurement cannot be made at a streamgage during high flows because of logistics or safety reasons, an indirect measurement of a peak discharge is useful for defining the high-flow section of the stage-discharge relation (rating curve) at the streamgage, resulting in more accurate computation of high flows. The Culvert Analysis Program (CAP) (Fulford, 1998) is a command-line program written in Fortran for computing peak discharges and culvert rating surfaces or curves. CAP reads input data from a formatted text file and prints results to another formatted text file. Preparing and correctly formatting the input file may be time-consuming and prone to errors. This document describes the CAP graphical user interface (GUI)—a modern, cross-platform, menu-driven application that prepares the CAP input file, executes the program, and helps the user interpret the output

  5. 公路桥涵汽车用电子限高报警系统(Ⅰ)——电子限高报警装置的原理与基本要求%Electronic Height Limit Alarm System of Highway Bridge Culvert Automobile(Ⅰ)——principle and essential requirements of electronic height limit alarm device

    Institute of Scientific and Technical Information of China (English)

    刘长生

    2011-01-01

    公路桥涵车用电子限高报警装置,是一种防止超高车辆撞坏桥涵的自动检测报警装置。文中描述这种专用电子限高装置的工作原理、基本要求以及常用的激光检测器与红外检测器的性能,为下一步进行设计公路桥涵车用电子限高报警装置提供必要的理论依据。%Electronic height limit alarm device of highway bridge culvert vehicle is an automatic detection and alarm device that prevents bridge and culver being destroyed by high vehicles.The working principles and essential requirements of the special device together with the performance of laser and infrared detectors commonly used were described in this paper,which could provide necessary theoretical basis for the design of electronic height limit alarm device applied in highway bridge culvert vehicles.

  6. 铁路营业线桥涵施工测斜技术研究及变形机制分析*%Study on Inclinometer Technology for Bridge and Culvert Construction on Operating Railway Line and Analysis of Deformation Mechanism

    Institute of Scientific and Technical Information of China (English)

    任高峰; 张卅卅; 胡仲春; 刘永成

    2014-01-01

    在铁路营业线桥涵施工中,采用人工挖孔桩上架设便梁作为施工加固体系,通过在南京宁启线某标段的下穿顶进涵施工中的实际运用,介绍了测斜仪的工作原理及应用,总结了测斜技术在铁路营业线桥涵施工中出现的若干关键问题,并分别从测斜管的布置、埋设、精度分析、采集频率、数据处理、预警预报等方面进行探讨,总结人工挖孔桩在土体开挖过程中及列车静、动荷载影响下的变形机制及位移规律,优化开挖施工方案,提高铁运及施工的安全性。%In the bridge and culvert construction on operating railway line, the buttress-girder temporary support system is used as the construction reinforcement. This paper introduces the application and working principle of portable digital inclinometer through the practical application in culvert jacking construction under somewhere on Nanjing Ningqi existing railway line. This paper summarizes a number of key issues of inclinometer technology in bridge and culvert construction on operating railway line and discusses from the aspects of the layout of inclinometer tube, laying design, accuracy analysis, collection frequency, data processing, early warning and forecasting;analyzes the deformation mechanism and displacement rule of manual hole digging pile under the impact of soil excavation and trains’ static and dynamic load, which optimizes the excavation and construction program, improves the safety of railway transportation.

  7. Movement and survival of an amphibian in relation to sediment and culvert design

    Science.gov (United States)

    Honeycutt, R.K; Lowe, W.H.; Hossack, Blake R.

    2016-01-01

    Habitat disturbance from stream culverts can affect aquatic organisms by increasing sedimentation or forming barriers to movement. Land managers are replacing many culverts to reduce these negative effects, primarily for stream fishes. However, these management actions are likely to have broad implications for many organisms, including amphibians in small streams. To assess the effects of culverts on movement and survival of the Idaho giant salamander (Dicamptodon aterrimus), we used capture-mark-recapture surveys and measured sediment in streams with 2 culvert types (i.e., unimproved culverts, improved culverts) and in streams without culverts (i.e., reference streams). We predicted culverts would increase stream sediment levels, limit movement, and reduce survival of Idaho giant salamanders. We also determined the effect of sediment levels on survival of salamanders because although sediment is often associated with distribution and abundance of stream amphibians, links with vital rates remain unclear. To estimate survival, we used a spatial Cormack–Jolly–Seber (CJS) model that explicitly incorporated information on movement, eliminating bias in apparent survival estimated from traditional (i.e., non-spatial) CJS models caused by permanent emigration beyond the study area. To demonstrate the importance of using spatial data in studies of wildlife populations, we compared estimates from the spatial CJS to estimates of apparent survival from a traditional CJS model. Although high levels of sediment reduced survival of salamanders, culvert type was unrelated to sediment levels or true survival of salamanders. Across all streams, we documented only 15 movement events between study reaches. All movement events were downstream, and they occurred disproportionately in 1 stream, which precluded measuring the effect of culvert design on movement. Although movement was low overall, the variance among streams was high enough to bias estimates of apparent survival

  8. Study on dynamic response of embedded long span corrugated steel culverts using scaled model shaking table tests and numerical analyses

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A series of scaled-model shaking table tests and its simulation analyses using dynamic finite element method were performed to clarify the dynamic behaviors and the seismic stability of embedded corrugated steel culverts due to strong earthquakes like the 1995 Hyogoken-nanbu earthquake. The dynamic strains of the embedded culvert models and the seismic soil pressure acting on the models due to sinusoidal and random strong motions were investigated. This study verified that the corrugated culvert model was subjected to dynamic horizontal forces (lateral seismic soil pressure) from the surrounding ground,which caused the large bending strains on the structure; and that the structures do not exceed the allowable plastic deformation and do not collapse completely during strong earthquake like Hyogoken-nanbu earthquake. The results obtained are useful for design and construction of embedded long span corrugated steel culverts in seismic regions.

  9. 78 FR 5715 - Construction and Maintenance-Culvert Pipe Selection

    Science.gov (United States)

    2013-01-28

    ... (39 FR 35152). According to Sec. 635.117(d), as in effect in 1974, Appendix A * * * sets forth the... installations. On September 10, 1976, this section was redesignated as 23 CFR 635.411 (41 FR 36204) and remained.... To implement this provision, the FHWA issued a final rule on November 15, 2006 (71 FR 66450),...

  10. ECOLOGICAL CRITERIA FOR PRIORITIZATION OF CULVERT REPLACEMENT

    Science.gov (United States)

    Culvert passage issues are gaining national and international focus, because they are implicated in the decline of particular species and in the more general loss of biodiversity in freshwater ecosystems. In the Pacific Northwest, inadequate fish passage at culverts is recognized...

  11. Dealing With Uncertainty When Assessing Fish Passage Through Culvert Road Crossings

    Science.gov (United States)

    Anderson, Gregory B.; Freeman, Mary C.; Freeman, Byron J.; Straight, Carrie A.; Hagler, Megan M.; Peterson, James T.

    2012-09-01

    Assessing the passage of aquatic organisms through culvert road crossings has become increasingly common in efforts to restore stream habitat. Several federal and state agencies and local stakeholders have adopted assessment approaches based on literature-derived criteria for culvert impassability. However, criteria differ and are typically specific to larger-bodied fishes. In an analysis to prioritize culverts for remediation to benefit imperiled, small-bodied fishes in the Upper Coosa River system in the southeastern United States, we assessed the sensitivity of prioritization to the use of differing but plausible criteria for culvert impassability. Using measurements at 256 road crossings, we assessed culvert impassability using four alternative criteria sets represented in Bayesian belief networks. Two criteria sets scored culverts as either passable or impassable based on alternative thresholds of culvert characteristics (outlet elevation, baseflow water velocity). Two additional criteria sets incorporated uncertainty concerning ability of small-bodied fishes to pass through culverts and estimated a probability of culvert impassability. To prioritize culverts for remediation, we combined estimated culvert impassability with culvert position in the stream network relative to other barriers to compute prospective gain in connected stream habitat for the target fish species. Although four culverts ranked highly for remediation regardless of which criteria were used to assess impassability, other culverts differed widely in priority depending on criteria. Our results emphasize the value of explicitly incorporating uncertainty into criteria underlying remediation decisions. Comparing outcomes among alternative, plausible criteria may also help to identify research most needed to narrow management uncertainty.

  12. Dealing with uncertainty when assessing fish passage through culvert road crossings

    Science.gov (United States)

    Anderson, Gregory B.; Freeman, Mary C.; Freeman, Byron J.; Straight, Carrie A.; Hagler, Megan M.; Peterson, James T.

    2012-01-01

    Assessing the passage of aquatic organisms through culvert road crossings has become increasingly common in efforts to restore stream habitat. Several federal and state agencies and local stakeholders have adopted assessment approaches based on literature-derived criteria for culvert impassability. However, criteria differ and are typically specific to larger-bodied fishes. In an analysis to prioritize culverts for remediation to benefit imperiled, small-bodied fishes in the Upper Coosa River system in the southeastern United States, we assessed the sensitivity of prioritization to the use of differing but plausible criteria for culvert impassability. Using measurements at 256 road crossings, we assessed culvert impassability using four alternative criteria sets represented in Bayesian belief networks. Two criteria sets scored culverts as either passable or impassable based on alternative thresholds of culvert characteristics (outlet elevation, baseflow water velocity). Two additional criteria sets incorporated uncertainty concerning ability of small-bodied fishes to pass through culverts and estimated a probability of culvert impassability. To prioritize culverts for remediation, we combined estimated culvert impassability with culvert position in the stream network relative to other barriers to compute prospective gain in connected stream habitat for the target fish species. Although four culverts ranked highly for remediation regardless of which criteria were used to assess impassability, other culverts differed widely in priority depending on criteria. Our results emphasize the value of explicitly incorporating uncertainty into criteria underlying remediation decisions. Comparing outcomes among alternative, plausible criteria may also help to identify research most needed to narrow management uncertainty.

  13. Brook trout passage performance through culverts

    Science.gov (United States)

    Goerig, Elsa; Castro-Santos, Theodore R.; Bergeron, Normand

    2016-01-01

    Culverts can restrict access to habitat for stream-dwelling fishes. We used passive integrated transponder telemetry to quantify passage performance of >1000 wild brook trout (Salvelinus fontinalis) attempting to pass 13 culverts in Quebec under a range of hydraulic and environmental conditions. Several variables influenced passage success, including complex interactions between physiology and behavior, hydraulics, and structural characteristics. The probability of successful passage was greater through corrugated metal culverts than through smooth ones, particularly among smaller fish. Trout were also more likely to pass at warmer temperatures, but this effect diminished above 15 °C. Passage was impeded at higher flows, through culverts with steep slopes, and those with deep downstream pools. This study provides insight on factors influencing brook trout capacity to pass culverts as well as a model to estimate passage success under various conditions, with an improved resolution and accuracy over existing approaches. It also presents methods that could be used to investigate passage success of other species, with implications for connectivity of the riverscape.

  14. Necropsy Report - Eaastern Pipistrelle Box Culvert I-55 Grenada, MS

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Necropsy report of a eastern pipisttrelle tricolored bat found dead in a box culvert along I55, near Grenada, MS provides no indication of whitenose syndrome.

  15. Analysis of Anticorrosion Technology of Bridge and Culvert Structures Concrete of Qinghai Chage Expressway Project in Saline Soil Area%青海察格高速公路项目工程桥涵构造物砼盐渍土地区防腐技术的分析借鉴

    Institute of Scientific and Technical Information of China (English)

    祁学英

    2012-01-01

    The northwest region of China is more extensive areas of saline land distribution, which is characterized by particularly severe of saline soil corrosion. The persecution role of the high concentrations intergranular brine or saline soil on pouring concrete highway is very strong. The sulfuric acid, salt and chloride in saline soil area has chemical action with cement, but also can bring damage caused by the physical role. Because the salt crystals is expanded in the wet and dry parts of structure and results in the crack in road concrete, it reduces the service life of the road to a large extent. So, except the relevant rules and norms of road construction in saline soil area, the corrosion resistance of concrete also should be paid great attention to and the special corresponding measures should be taken when conditions permit to mitigate and even eradicate the destructive effects of corrosion on highway structures.%我国的西北部是盐碱地分布比较广泛的地区,其特点就是盐渍土的腐蚀尤其严重.高浓度晶间卤水或者盐渍土壤对由混凝土浇筑的高速公路的的迫害作用相当强.这样的盐渍土地区环境中的硫酸、盐和氯盐和水泥石极易发生化学作用,而且还有物理作用造成的破坏,因为盐类结晶在结构的干湿变化部位基因膨胀,造成公路混凝土开裂,很大程度的减少了公路的使用寿命.所以说,对于盐渍土地区的公路建设各有关规定和规范之外,还须对混凝土地防腐性能给予高度关注,在条件许可时采取特殊对应措施,减轻乃至根除腐蚀对公路构筑物的破坏作用.

  16. Do culverts impact the movements of the endangered white-clawed crayfish?

    Directory of Open Access Journals (Sweden)

    Louca V.

    2014-01-01

    Full Text Available Culverts can impact the migration and dispersal of aquatic animals and result in population fragmentation, increasing the risk of local extinction for endangered species such as the white-clawed crayfish Austropotamobius pallipes. This study used radio telemetry and passive integrated transponder (PIT telemetry to determine whether existing and experimental covered culverts affect the upstream and downstream movements of adult white-clawed crayfish. Daily crayfish movement rates did not differ significantly between an unlit 363-m long culvert and open stream channel sections. Crayfish moved into dark, covered sections volitionally. However, limited upstream movement occurred at sudden transitions of bed height or smooth-concrete box culvert sections with fast flow, suggesting partial barrier effects. In the 20-m long experimental in-stream culvert, also dark, but with natural stream bed, 70% of radio-tagged crayfish released downstream entered the culvert, as did 60% of those released upstream. Overall 35% passed through, with similar numbers in each direction. We conclude that dark culverts up to several hundred metres do not inhibit dispersal of white-clawed crayfish, provided stream slope, bed type and water velocity are amenable for movement and refuge. Care is required to ensure that culverts are bioengineered to ensure that average water velocity is sufficiently low and local hydraulic variation high, the bed and/or sidewalls contain refuge structures, and there are no cross-channel steps in bed level. Smooth-bedded box culverts are unlikely to be suitable for white-clawed crayfish.

  17. Feasibility of culvert IED detection using thermal neutron activation

    Science.gov (United States)

    Faust, Anthony A.; McFee, John E.; Clifford, Edward T. H.; Andrews, Hugh Robert; Mosquera, Cristian; Roberts, William C.

    2012-06-01

    Bulk explosives hidden in culverts pose a serious threat to the Canadian and allied armies. Culverts provide an opportunity to conceal insurgent activity, avoid the need for detectable surface disturbances, and limit the applicability of conventional sub-surface sensing techniques. Further, in spite of the large masses of explosives that can be employed, the large sensor{target separation makes detection of the bulk explosive content challeng- ing. Defence R&D Canada { Sueld and Bubble Technology Industries have been developing thermal neutron activation (TNA) sensors for detection of buried bulk explosives for over 15 years. The next generation TNA sensor, known as TNA2, incorporates a number of improvements that allow for increased sensor-to-target dis- tances, making it potentially feasible to detect large improvised explosive devices (IEDs) in culverts using TNA. Experiments to determine the ability of TNA2 to detect improvised explosive devices in culverts are described, and the resulting signal levels observed for relevant quantities of explosives are presented. Observations conrm that bulk explosives detection using TNA against a culvert-IED is possible, with large charges posing a detection challenge at least as dicult as that of a deeply buried anti-tank landmine. Because of the prototype nature of the TNA sensor used, it is not yet possible to make denitive statements about the absolute sensitivity or detection time. Further investigation is warranted.

  18. Application of a multistate model to estimate culvert effects on movement of small fishes

    Science.gov (United States)

    Norman, J.R.; Hagler, M.M.; Freeman, Mary C.; Freeman, B.J.

    2009-01-01

    While it is widely acknowledged that culverted road-stream crossings may impede fish passage, effects of culverts on movement of nongame and small-bodied fishes have not been extensively studied and studies generally have not accounted for spatial variation in capture probabilities. We estimated probabilities for upstream and downstream movement of small (30-120 mm standard length) benthic and water column fishes across stream reaches with and without culverts at four road-stream crossings over a 4-6-week period. Movement and reach-specific capture probabilities were estimated using multistate capture-recapture models. Although none of the culverts were complete barriers to passage, only a bottomless-box culvert appeared to permit unrestricted upstream and downstream movements by benthic fishes based on model estimates of movement probabilities. At two box culverts that were perched above the water surface at base flow, observed movements were limited to water column fishes and to intervals when runoff from storm events raised water levels above the perched level. Only a single fish was observed to move through a partially embedded pipe culvert. Estimates for probabilities of movement over distances equal to at least the length of one culvert were low (e.g., generally ???0.03, estimated for 1-2-week intervals) and had wide 95% confidence intervals as a consequence of few observed movements to nonadjacent reaches. Estimates of capture probabilities varied among reaches by a factor of 2 to over 10, illustrating the importance of accounting for spatially variable capture rates when estimating movement probabilities with capture-recapture data. Longer-term studies are needed to evaluate temporal variability in stream fish passage at culverts (e.g., in relation to streamflow variability) and to thereby better quantify the degree of population fragmentation caused by road-stream crossings with culverts. ?? American Fisheries Society 2009.

  19. Assessing Juvenile Salmonid Passage Through Culverts: Field Research in Support of Protocol Development

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Greg D.; Evans, Nathan R.; Pearson, Walter H.; Southard, John A.

    2001-10-30

    The primary goal of our research this spring/ summer was to refine techniques and examine scenarios under which a standardized protocol could be applied to assess juvenile coho salmon (O. kisutch) passage through road culverts. Field evaluations focused on capture-mark- recapture methods that allowed analysis of fish movement patterns, estimates of culvert passability, and potential identification of cues inducing these movements. At this stage, 0+ age coho salmon fry 30 mm to 65 mm long (fork length) were the species and age class of interest. Ultimately, the protocol will provide rapid, statistically rigorous methods for trained personnel to perform standardized biological assessments of culvert passability to a number of juvenile salmon species. Questions to be addressed by the research include the following: ? Do hydraulic structures such as culverts restrict habitat for juvenile salmonids? ? How do existing culverts and retrofits perform relative to juvenile salmonid passage? ? Do some culvert characteristics and hydraulic conditions provide better passage than others? ? Does the culvert represent a barrier to certain size classes of fish? Recommendations addressed issues of study site selection, initial capture, marking, recapture/observations, and estimating movement.

  20. Characterization of Turbulent Open Channel Flow in a Full-Scale Spiral Corrugated Culvert

    Energy Technology Data Exchange (ETDEWEB)

    Guensch, Greg R.; Richmond, Marshall C.; Tritico, Hans; Pearson, Walter H.

    2004-02-26

    A micro-Acoustic Doppler Velocimeter (ADV) was used to characterize the three-dimensional velocity and turbulence characteristics in a full-scale culvert with spiral corrugations. The culvert was set up in a test bed constructed to examine juvenile salmon passage success in various culvert types. The test culvert was 12.2 m long and 1.83m in diameter, and set at a 1.14% slope. The corrugations were 2.54 cm deep by 7.62 cm peak to peak with a 5° right-handed pitch. Tailwater elevation was adjustable with a stop-log system and was set slightly above the water surface level at the culvert exit. Cross-sectional grids of ADV measurements were taken at discharges of 28, 57, 113, 227, and 453 lps at 9 locations within the culvert barrel and just inside the headwater and tailwater tanks. Results indicated that the spiral corrugations induced asymmetries in the velocity and turbulence distributions. These asymmetries caused a Reduced Velocity Zone (RVZ) on the right side of the culvert as seen looking upstream, which could aid small fish during upstream passage. Velocity and turbulence levels in the RVZ were found to be less than in mid channel or on the left side of the culvert, and the difference became greater at increased flow rates. Lateral and vertical velocity components were very small relative to the axial component, while lateral and vertical turbulence intensities were comparable to the axial component. Inlet loss coefficients were calculated as well and ranged from 0.32 to 0.42. Relationships between the average velocity and the velocity and turbulence intensity in the RVZ were developed, which may be useful for evaluating whether the barrel of a culvert is passable for juvenile fish.

  1. Integral Abutment and Jointless Bridges

    OpenAIRE

    Cristian-Claudiu Comisu

    2005-01-01

    Integral bridges, or integral abutment and jointless bridges, as they are more commonly known in the USA, are constructed without any movement joints between spans or between spans and abutments. Typically these bridges have stub-type abutments supported on piles and continuous bridge deck from one embankment to the other. Foundations are usually designed to be small and flexible to facilitate horizontal movement or rocking of the support. Integrally bridges are simple or multiple span ones t...

  2. 填土高度、跨径对盖板涵涵台结构的影响%The Filling Height and Span Effect on the Slab Culvert Structure

    Institute of Scientific and Technical Information of China (English)

    蒋丽飞

    2014-01-01

    本文针对盖板涵设计,讨论了填土高度、跨径对涵台结构的影响。结果表明:在一定范围内,填土高度越大,对结构受力越有利。但超过该范围,填土高度越大,对结构受力越不利。跨径大对涵台结构受力有利,但对盖板结构受力不利。%In view of the slab culvert design, this article discusses the influence of fil ing height and span of culvert structure. The results show that within a certain range, the greater of the fil ing height, the bet er for the structure stress. But if over the range, the greater of the fil ing height, the worse to the structure stress. Large span is benefit for the culvert structure stress, but bad for the flat structure.

  3. Analysis of brook trout spatial behavior during passage attempts in corrugated culverts using near-infrared illumination video imagery

    Science.gov (United States)

    Bergeron, Normand E.; Constantin, Pierre-Marc; Goerig, Elsa; Castro-Santos, Theodore R.

    2016-01-01

    We used video recording and near-infrared illumination to document the spatial behavior of brook trout of various sizes attempting to pass corrugated culverts under different hydraulic conditions. Semi-automated image analysis was used to digitize fish position at high temporal resolution inside the culvert, which allowed calculation of various spatial behavior metrics, including instantaneous ground and swimming speed, path complexity, distance from side walls, velocity preference ratio (mean velocity at fish lateral position/mean crosssectional velocity) as well as number and duration of stops in forward progression. The presentation summarizes the main results and discusses how they could be used to improve fish passage performance in culverts.

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

    DEFF Research Database (Denmark)

    Du, Guangli; Karoumi, Raid

    2013-01-01

    not been integrated into the decision-making process. This paper presents a systematic LCA method for quantifying the environmental impacts for bridges. The comparison study is performed between a reinforced concrete bridge and a steel bridge as an alternative design, with several key maintenance and EOL......The concept of sustainable construction has attracted an increased attention. Bridge infrastructures and their belonged construction activities consume considerable material and energy, which is responsible for large environmental burdens. However, the environmental assessment of bridges has...

  5. Bottom ash from fluidising bed boilers as filler material in district heating pipe culverts. Chemical and geotechnical characterisation; Pannsand som kringfyllnadsmaterial foer fjaerrvaermeroergravar. Kemisk och geoteknisk karaktaerisering av fluidbaeddsand

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Roger; Rogbeck, Jan; Suer, Pascal

    2004-01-01

    Bottom ashes from fluid bed boilers have been characterised, both geotechnically and chemically, in order to investigate the possibility to use them as filler material in district heating pipe culverts. Bottom ashes from both biofuel boilers and waste boilers are represented in this project. The companies which ashes have been characterised are Sundsvall Energi AB, Sydkraft OestVaerme AB, Sydkraft MaelarVaerme AB, Eskilstuna Miljoe och Energi, Stora Enso Fors, Soederenergi and Fortum Vaerme. A total of ten ashes have been analysed where three ashes originates from Sundsvall Energi AB, two from Sydkraft OestVaerme AB and one from the each of the remaining companies. The chemical analyses have been performed both on fresh ashes and on ashes aged for three months. The geotechnical analyses performed are grain size distribution, packing abilities and permeability. Chemical analyses performed are total content, available content, leaching tests (leaching both by shaking method and column procedure) and organic analyses (PAH, EOX, TOC, dioxin and fenol). The geotechnical analyses show that the ashes fulfils the demands that are put on the filler material used in district heating pipe culverts. When using the ashes in applications, light compaction should be performed due to the risk of crushing the material which may cause an increased amount of fine material. The leachability of fine material is larger than for coarse material. The ashes are relatively insensitive to precipitation. Bio fuel based bottom ashes have a lower content of environmental affecting substances than waste fuel based ashes. This is also shown in the leaching analyses. The leaching water from fresh ashes contains a higher concentration of leachable components than aged ashes. When aged the pH in the ashes decreases due to carbon uptake and hydration and this makes metals as Pb, Cu, Cr and Zn less mobile. On the other hand, an increase in leachability of Sb, Mo and SO{sub 4} is shown when the ashes

  6. Study on Dynamic Response and Scope of the Transition between Culvert and Subgrade in Beijing-Shanghai High-speed Railway%京沪高速铁路路涵过渡段动态响应特征及影响范围研究

    Institute of Scientific and Technical Information of China (English)

    田亚护; 陈茂; 沈宇鹏; 杜嘉俊; 蔡小培

    2014-01-01

    针对高速铁路的桥涵与临近路基由于存在材料和沉降的差异形成的刚度和几何不平顺,对路涵过渡段的动态响应和影响范围进行研究。本文建立“车辆-轨道-过渡段”垂向耦合动力模型,研究过渡段路基的动态响应特征,并与京沪高速铁路廊坊段路涵过渡段现场实测值进行对比。结果表明,当运行速度小于300 km/h 时,过渡段基床动应力、加速度、垂向位移等随速度增加而增大;在300 km/h 时动应力、加速度出现最大值,动位移随行车速度呈线性增大;从动应力、加速度的影响范围看,运行速度在300 km/h 以下时路涵过渡段影响范围为20~25 m,300 km/h 及以上时,过渡段长度达到30~35 m。当设计速度超过300 km/h 时,应适当加长路涵过渡段长度。%According to the situation that there are stiffness and geometrical irregularities in the transition between subgrade and culvert /bridge due to the differences in material and deformation,researches on transition be-tween culvert and subgrade are carried out.In this paper,the vertical coupling dynamic model of vehicle-track-transitional section was built to sudy the characteristics of dynamic responses in transitional section between culvert and subgrade.Then,the results of the model were comparied with field tests of conducted in the Lang-fang segment of the Beijing-Shanghai High-speed Railway Line.The results show as follows:When a train runs at a speed lower than 300 km/h,the dynamic stress,acceleration and vertical displacement in transition increase with raizing of the train speed;when at the speed of 300 km/h,the dynamic stress and acceleration reach the maximum and the dynamic displacement increases linearly with raizing of the train speed;referting to the influence scope of the dynamic stress and acceleration in the transitional section,it covers 20 ~ 25 m at the speeds of 300 km/h and less and extends to 30 ~ 35 m at the speeds of higher than 300

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

    Data.gov (United States)

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

  8. Cause analysis of cracks in circulating water culvert of Daya Bay Nuclear Power Station

    International Nuclear Information System (INIS)

    In view of the widespread cracks discovered in the reinforced-concrete circulating water culvert of Daya Bay Nuclear Power Station, cause analysis for the cracks is made in terms of construction and design. It is concluded that the cracks mainly resulted from shrinkage and temperature. Corresponding countermeasures are put forward thereafter for reference of similar projects

  9. Longitudinal habitat disruption in Neotropical streams: fish assemblages under the influence of culverts

    Directory of Open Access Journals (Sweden)

    José Roberto Mariano

    2012-10-01

    Full Text Available This study assessed differences in fish assemblages existing upstream and downstream two types of culverts, one on each of two different Neotropical streams. We analyzed the composition and structure of the ichthyofauna and tested for spatial patterns. Fish sampling was carried out monthly between November 2009 and October 2010 using different fishing gears. We collected 2,220 fish of 33 species; 901 in stretches of the Lopeí stream - circular culvert and 1,310 in stretches of the Pindorama stream - box culvert. Fish abundance was similar in upstream and downstream stretches of the circular culvert, whereas it was slightly higher in the upstream than downstream stretch for the box culvert. Characiformes predominated in the upstream stretch of both culverts. On the other hand, Siluriformes was abundant in the downstream stretch of the circular culvert, with similar abundance in the stretches of the box culvert. Species richness and diversity (Shannon-Weiner Index were higher in the downstream stretch of the circular culvert, but they were similar in both stretches of the box culvert. The most abundant species were Astyanax altiparanae, A. paranae, A. fasciatus, Ancistrus sp., and Hypostomus sp. The last two species were more abundant in the downstream stretch of the circular culvert, and similar in stretches of the box culvert. Our study indicated variations in the species abundance, richness, and diversity between upstream and downstream stretches in particular of the circular culvert in the Lopeí stream, suggesting that fish movements are restrained more intensively in this culvert, especially for Siluriformes. The drop in the circular culvert outlet probably created passage barriers especially for those fish that has no ability to jump, where downstream erosion could lead to culvert perching. Studies on appropriate road crossing design or installation are fundamental whereas improvements in these structures can restore the connectivity of

  10. Culverts in paved roads as suitable passages for Neotropical fish species

    Directory of Open Access Journals (Sweden)

    Sergio Makrakis

    2012-10-01

    Full Text Available Improperly installed or poorly maintained culverts can pose a serious threat to fish by disrupting their habitat and endangering spawning success. Road culverts that are not designed for fish passage frequently can become obstacles. This can be especially problematic for migratory species, but can lead to fragmentation of resident populations as well. This study evaluated 40 culverts of 29 sites within a 25-km radius from Toledo city, Paraná State, southern Brazil, with respect to their likely effects on movement of the local ichthyofauna. We collected data on the shape and length of culverts, culvert material, waterfall height, water column depth, slope, and estimated flow velocity. Culverts were categorized by level of barrier risk for upstream migration: high, medium, low, and impassable, as well as the type of barrier posed (fall height, depth, length and velocity. Most of culverts analyzed were considered potential barriers to fish movement, with 45% classified as impassible, 45% as high risk, 10% as medium risk, and no culverts as low risk. Brazilian culverts as fishways will require additional monitoring and studies to corroborate the premises proposed in the present study. Road culvert projects that are properly built and maintained will be able to simultaneously improve function of roadways and protect fish populations.Bueiros incorretamente instalados ou mal conservados podem representar uma séria ameaça para os peixes por fragmentar o seu habitat e comprometer o sucesso da desova. Bueiros em estradas que não são projetados para passagem de peixes freqüentemente tornam-se obstáculos. Isso pode ser especialmente problemático para as espécies migratórias, mas também pode levar à fragmentação das populações de peixes residentes. Este estudo avaliou 29 locais com 40 bueiros dentro de um raio de 25 km de Toledo, Estado do Paraná, sul do Brasil, com relaç��o aos seus prováveis efeitos sobre a movimentação da

  11. Bridging history and social psychology

    DEFF Research Database (Denmark)

    Glaveanu, Vlad Petre; Yamamoto, Koji

    2012-01-01

    This special issue aims to bridge history and social psychology by bringing together historians and social psychologists in an exercise of reading and learning from each other’s work. This interdisciplinary exercise is not only timely but of great importance for both disciplines. Social...... hand historians can enhance their analysis of historical sources by drawing upon the conceptual tools developed in social psychology. They can “test” these tools and contribute to their validation and enrichment from completely different perspectives. Most important, as contributions to this special......-traditionalized societies—a distinction that lies at the heart of many social psychology accounts of the world we live in. The present editorial will introduce and consider this act of bridging history and social psychology by focusing on three main questions: What is the bridge made of? How can the two disciplines...

  12. Bridge Number and Conway Products

    OpenAIRE

    Blair, Ryan C.

    2007-01-01

    Schubert proved that, given a composite link $K$ with summands $K_{1}$ and $K_{2}$, the bridge number of $K$ satisfies the following equation: $$\\beta(K)=\\beta(K_{1})+\\beta(K_{2})-1.$$ In ``Conway Produts and Links with Multiple Bridge Surfaces", Scharlemann and Tomova proved that, given links $K_{1}$ and $K_{2}$, there is a Conway product $K_{1}\\times_{c}K_{2}$ such that $$\\beta(K_{1}\\times_{c} K_{2}) \\leq \\beta(K_{1}) + \\beta(K_{2}) - 1$$ In this paper, we define the generalized Conway prod...

  13. Removal of failed crown and bridge.

    Science.gov (United States)

    Sharma, Ashu; Rahul, G R; Poduval, Soorya T; Shetty, Karunakar

    2012-07-01

    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

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

    Science.gov (United States)

    Matsutani, Akihiro

    2004-05-01

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

  15. Parabolic metamaterials and Dirac bridges

    Science.gov (United States)

    Colquitt, D. J.; Movchan, N. V.; Movchan, A. B.

    2016-10-01

    A new class of multi-scale structures, referred to as `parabolic metamaterials' is introduced and studied in this paper. For an elastic two-dimensional triangular lattice, we identify dynamic regimes, which corresponds to so-called `Dirac Bridges' on the dispersion surfaces. Such regimes lead to a highly localised and focussed unidirectional beam when the lattice is excited. We also show that the flexural rigidities of elastic ligaments are essential in establishing the `parabolic metamaterial' regimes.

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

    Institute of Scientific and Technical Information of China (English)

    Shunquan Qin; Pu Zhou; Youheng Hua

    2004-01-01

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

  17. Bridging Block and Bundesen

    DEFF Research Database (Denmark)

    Sørensen, Thomas Alrik

    that some fields in cognitive science are already gaining ground on the hard problem. An interesting model is Claus Bundesen‘s (1990) Theory of Visual Attention (TVA) that seems to be compatible with Ned Block‘s (1995) distinction between access consciousness and phenomenal consciousness. TVA proposes a two......-part stochastic model where 1) every stimulus is given a weight in terms of belonging to a certain visual category and 2) every stimulus then enters a race for a place in a limited-capacity visual short-term memory store. TVA seems to be a good model to describe access consciousness; by expanding this model......Consciousness seems to present a special challenge for scientific investigation. Much research has been done on the so-called "easy" aspects of consciousness such as perception, attention, and memory. The "hard problem", however, still seems to elude scientific methods. In this paper I argue...

  18. Dynamics and Statics of Nonaxisymmetric Liquid Bridges

    Science.gov (United States)

    Alexander, J. Iwan D.; Resnick, Andrew H.; Slobozhanin, L. A.

    1996-01-01

    Theoretical and experimental investigation of the stability of nonaxisymmetric and nonaxisymmetric bridges contained between equal and unequal radii disks as a function of Bond and Weber number with emphasis on the transition from unstable axisymmetric to stable nonaxisymmetric shapes, are conducted. Numerical analysis of the stability of nonaxisymmetric bridges between unequal disks for various orientations of the gravity vector is performed. Experimental and theoretical investigation of large (nonaxisymmetric) oscillations and breaking of liquid bridges are also conducted.

  19. Bridge engineering handbook construction and maintenance

    CERN Document Server

    Chen, Wai-Fah

    2014-01-01

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

  20. Axisymmetric long liquid bridges stability and resonances

    OpenAIRE

    Meseguer Ruiz, José; Sanz Andres, Angel Pedro; Perales Perales, José Manuel

    1990-01-01

    In this paper mathematical expressions for minimum-volume stability limits and resonance frequencies of axisymmetric long liquid bridges are presented. These expressions are valid for a wide range of liquid bridge configurations, accounting for ef-fects like unequal disks and axial microgravity in the case of minimum-volume stability limits,and unequal disks, axial microgravity,non-zero viscosity and liquid bridge volume different from the cylindrical one in the case of resonance frequenc...

  1. Fish Movement Ecology in High Gradient Headwater Streams: Its Relevance to Fish Passage Restoration through Stream Culvert Barriers

    Science.gov (United States)

    Hoffman, Robert L.; Dunham, Jason B.

    2007-01-01

    Executive Summary Restoration of fish passage through culvert barriers has emerged as a major issue in the Pacific Northwest and nationwide. The problem has many dimensions, including the huge number of potential barriers, uncertainty about which structures are actually barriers, the benefits and risks involved with restoration, and the financial costs and timelines. This report attempts to address what we call 'thinking outside of the pipe' in terms of fish passage information needs. This means understanding the value of each potential passage restoration project in the context of other possible projects, and to view individual restoration projects within a larger landscape of habitats and population processes. In this report we provide a brief review of some essential characteristics of animal movement and examples from a focal group of fishes in Washington State: salmon, trout, and char. While several other fishes and many other species use streams where culvert passage barriers may occur, it is the salmonids that are by far the most widespread and in most cases extending furthest into the headwaters of stream networks in Washington. We begin this report by outlining some basic characteristics of animal movement and then apply that foundation to the case of salmonid fishes. Next we consider the consequences of disrupting fish movement with human-constructed barriers, such as culverts. Finally, this body of evidence is summarized and we propose a short list of what we view as high priority information needs to support more effective restoration of fish passage through culverts.

  2. 船闸短廊道输水系统进口漩涡成因及消除措施研究%Causes and Eliminating Measures of Vortices at the Intake of Short Culvert Conveyance System of Shiplock

    Institute of Scientific and Technical Information of China (English)

    吴英卓; 江耀祖; 周赤; 蒋筱民

    2011-01-01

    以兴隆船闸为例,通过物理模型试验研究,对短廊道输水系统进口漩涡成因进行了探讨,分析了输水阀门运行条件、进口淹没水深、进口形式及固体边界条件对漩涡形态的影响.通过模型试验比较,最终提出了适当增加进口淹没深度同时在进口顶部设置开孔式消涡板等措施,可消除吸气漩涡,为优化设计和运行管理提供了依据,并可为其它类似工程设计提供参考.%Physical model tests were performed to discuss the causes of vortices at the intake of short culvert conveyance system of the shiplock at Xinglong hydro-junction. Effects of the operating mode of the water valve, the submerged water depth at the intake, and the intake shape and solid boundary conditions on the vortex pattern were analyzed. By comparing a series of model tests, measures of properly increasing the submerged water depth at the intake while setting vortex plate at the top of the intake were finally proposed to eliminate the air-inhaling vortices. It provided basis for the optimal design and operation management and could be referential for the design of alike projects.

  3. Building bridgesand accelerators

    CERN Multimedia

    2009-01-01

    Lyn Evans, the LHC project leader, was awarded an honorary doctorate from the University of Geneva (UNIGE) to celebrate his role not just in building accelerators, but also in building bridges between nations. He was one of four notables honoured at the event on Friday 5 June, coinciding with the University’s 450th Anniversary. Lyn Evans arriving at the ceremony with Archbishop Desmond Tutu. "It was a big surprise when I found out I’d been nominated," recounts Evans, "but it was an even bigger surprise to find out with whom I’d been nominated". At the ceremony Evans was awarded the honorary doctorate along with three others: Archbishop Desmond Tutu, who was acclaimed for his fight against apartheid in South Africa, Mary Robinson, first woman president of Ireland and former United Nations’ high commissioner of human rights, and Pascal Lamy, Director-General of the World Trade Organization. The award ceremony, known as the �...

  4. Numerical analysis of dynamic response of vehicle–bridge coupled system on long-span continuous girder bridge

    Directory of Open Access Journals (Sweden)

    Lipeng An

    2016-07-01

    Full Text Available To systematically study the vehicle–bridge coupled dynamic response and its change rule with different parameters, a vehicle model with seven degrees of freedom was built and the total potential energy of vehicle space vibration system was deduced. Considering the stimulation of road roughness, the dynamic response equation of vehicle–bridge coupled system was established in accordance with the elastic system principle of total potential energy with stationary value and the “set-in-right-position” rule. On the basis of the self-compiled Fortran program and bridge engineering, the dynamic response of long-span continuous girder bridge under vehicle load was studied. This study also included the calculation of vehicle impact coefficient, evaluation of vibration comfort, and analysis of dynamic response parameters. Results show the impact coefficient changes with lane number and is larger than the value calculated by the “general code for design of highway bridges and culverts (China”. The Dieckmann index of bridge vibration is also related to lane number, and the vibration comfort evaluation is good in normal conditions. The relevant conclusions from parametric analyses have practical significance to dynamic design and daily operation of long-span continuous girder bridges in expressways. Safety and comfort are expected to improve significantly with further control of the vibration of vehicle–bridge system.

  5. Signal and noise in bridging PCR

    Directory of Open Access Journals (Sweden)

    Thaler David S

    2002-07-01

    Full Text Available Abstract Background In a variant of the standard PCR reaction termed bridging, or jumping, PCR the primer-bound sequences are originally on separate template molecules. Bridging can occur if, and only if, the templates contain a region of sequence similarity. A 3' end of synthesis in one round of synthesis that terminates in this region of similarity can prime on the other. In principle, Bridging PCR (BPCR can detect a subpopulation of one template that terminates synthesis in the region of sequence shared by the other template. This study considers the sensitivity and noise of BPCR as a quantitative assay for backbone interruptions. Bridging synthesis is also important to some methods for computing with DNA. Results In this study, BPCR was tested over a 328 base pair segment of the E. coli lac operon and a signal to noise ratio (S/N of approximately 10 was obtained under normal PCR conditions with Taq polymerase. With special precautions in the case of Taq or by using the Stoffel fragment the S/N was improved to 100, i.e. 1 part of cut input DNA yielded the same output as 100 parts of intact input DNA. Conclusions In the E. coli lac operator region studied here, depending on details of protocol, between 3 and 30% per kilobase of final PCR product resulted from bridging. Other systems are expected to differ in the proportion of product that is bridged consequent to PCR protocol and the sequence analyzed. In many cases physical bridging during PCR will have no informational consequence because the bridged templates are of identical sequence, but in a number of special cases bridging creates, or, destroys, information.

  6. Human Errors and Bridge Management Systems

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Nowak, A. S.

    Human errors are divided in two groups. The first group contains human errors, which effect the reliability directly. The second group contains human errors, which will not directly effect the reliability of the structure. The methodology used to estimate so-called reliability distributions...... on basis of reliability profiles for bridges without human errors are extended to include bridges with human errors. The first rehabilitation distributions for bridges without and with human errors are combined into a joint first rehabilitation distribution. The methodology presented is illustrated...

  7. Bridge Aesthetics and Structural Honesty

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1999-01-01

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

  8. Differing Levels of Forestry Best Management Practices at Stream Crossing Structures Affect Sediment Delivery and Installation Costs

    Directory of Open Access Journals (Sweden)

    Brian C. Morris

    2016-03-01

    Full Text Available Forestry best management practices (BMPs are used to reduce sedimentation from forest stream crossings. Three BMP treatments (BMP−, BMP-std, and BMP+ were applied to three forest road stream crossings (bridge, culvert, and ford. BMP− did not meet existing BMP guidelines, BMP-std met standard recommendations, and BMP+ treatments exceeded recommendations. Following BMP applications, three simulated rainfall intensities (low, medium, and high were applied in order to evaluate sediment delivery from crossing type and BMP level. During rainfall simulation, sediment concentrations (mg/L were collected with automated samplers and discharge (L/s was estimated to calculate total sediment loading. Costs of stream crossings and BMP levels were also quantified. Mean sediment associated with the three stream crossings were 3.38, 1.87, and 0.64 Mg for the BMP−, BMP-std, and BMP+ levels, respectively. Ford, culvert, and bridge crossings produced 13.04, 12.95, and 0.17 Mg of sediment during construction, respectively. BMP enhancement was more critical for sediment control at the culvert and ford crossings than at the bridge. Respective costs for BMP−, BMP-std, and BMP+ levels were $5,368, $5,658, and $5,858 for the bridge; $3,568, $4,166 and $4,595 for the culvert; and $180, $420 and $1,903 for the ford. Costs and sediment values suggest that current standard BMP levels effectively reduce stream sediment while minimizing costs.

  9. Assessment of a Bridge WIM System on Integral Concrete Bridges and on Steel Orthotropic Decks

    OpenAIRE

    Ieng, Sio Song; SCHMIDT, Franziska; ROMBONI, Frédéric; Jacob, Bernard

    2011-01-01

    Bridge-Weigh-In-Motion uses bridges as a scale to weigh vehicles. Practically, this is done by measuring the strains in that bridge, and relating them to the weight and dimensions of a truck called “calibration trucks” whose shape and axle weights are well known. This article summarizes different B-WIM experiments the institute IFSTTAR (formerly called LCPC) realized and the lessons drawn from this experience. First, the system has been tested on frame-type bridges with integral s...

  10. Bridging radiation policy and science

    International Nuclear Information System (INIS)

    Scientists, regulators, and policy makers from five continents and 20 countries reached consensus on a number of conclusions and recommendations regarding low-level ionizing radiation exposures at an international conference, 'Bridging Radiation Policy and Science,' at the Airlie Center in Warrenton, Virginia, 1-5 December 1999. The goal of the conference was to develop strategies for formulating national and international policy based on current scientific information in the context of economic, political, and social concerns. Specifically, attendees explored how to establish public policies with respect to radiation protection in view of the scientific uncertainties of the effects of low-level radiation [<100 millisievert (mSv)]. Conference participants agreed that science will not likely answer in the near future fundamental questions about the shape of the dose-response curve and mechanisms of effects of radiation at low doses. The conference endorsed the quest for a prudent and coherent radiation policy based on the International Atomic Energy Agency's (IAEA) 'evolving global framework'. The Conference participants agreed upon the following recommendations: Policy discussions on the regulation of radiation sources delivering low-level radiation should include references to natural background radiation. The conference supports the evolving global framework of the International Atomic Energy Agency (IAEA) for the safe use of radiation. The conference supports further development and evaluation of the ideas associated with the proposal on controllable dose. No radiation dose is below regulatory concern but certain levels should be below regulatory action, and appropriate dose levels should be established. Fundamental questions about the shape of the dose-response curve and mechanisms of effects of radiation at low doses are unlikely to be answered in the near future. Scientific research, including molecular and cellular radiobiology studies are critical in order

  11. Remaining Sites Verification Package for the 100-F-50 Stormwater Runoff Culvert, Waste Site Reclassification Form 2007-001

    Energy Technology Data Exchange (ETDEWEB)

    J. M. Capron

    2008-04-15

    The 100-F-50 waste site, part of the 100-FR-2 Operable Unit, is a steel stormwater runoff culvert that runs between two railroad grades in the south-central portion of the 100-F Area. The culvert exiting the west side of the railroad grade is mostly encased in concrete and surrounded by a concrete stormwater collection depression partially filled with soil and vegetation. The drain pipe exiting the east side of the railroad grade embankment is partially filled with soil and rocks. The 100-F-50 stormwater diversion culvert confirmatory sampling results support a reclassification of this site to no action. The current site conditions achieve the remedial action objectives and corresponding remedial action goals established in the Remaining Sites ROD. The results of confirmatory sampling show that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also demonstrate that residual contaminant concentrations are protective of groundwater and the Columbia River.

  12. MINERAL BRIDGES OF NACRE AND ITS EFFECTS

    Institute of Scientific and Technical Information of China (English)

    宋凡; 白以龙

    2001-01-01

    Nacre, or mother-of-pearl, is a kind of composites of aragonite platelets sandwiched between organic materials. Its excellent mechanical properties are thought to stem from the microarchitecture that is traditionally described as a "brick and mortar" arrangement. In this paper, a new microstructure, referred to as mineral bridge in the biomineralization, is directly observed in the organic matrix layers (mortar) of nacre. This is an indication that the organic matrix layer of nacre should be treated as a three-dimensional interface and the microarchitecture of nacre ought to be considered as a "brick-bridge-mortar" structure rather than the traditional one. Experiments and analyses show that the mineral bridges not only improve the mechanical properties of the organic matrix layers but also play an important role in the pattern of the crack extension in nacre.

  13. Journaling: A Bridge between School and Home

    Science.gov (United States)

    McGough, Julie

    2013-01-01

    This article describes how first-grade students create meaningful communication with families and help build the student-teacher-parent relationship through journaling. Journals are a useful tool to bridge school and home. A journal can communicate learning goals, develop scientific vocabulary, and create dialogue through oral and written…

  14. Bridging the Gap Between Theory and Practice

    Directory of Open Access Journals (Sweden)

    Roy H.M. Sembel

    2015-05-01

    Full Text Available Some concerns in the field of Business Management regarding the gap between theory and practice have been raised by practitioners and academicians. This keynote speech describes some lessons learned from the academic literature regarding this gap (whether the gap really exists, and if it exists, whether it needs to be bridged or closed, and how to bridge or close this gap, and shares the author's personal and professional experiences of living as both an academician and a practitioner. The main findings of this article are: (1 Yes the gap exists, however, it has to be viewed in a wider perspective to really understand the situation; (2 The gap in a specific area is bad and should become our concern, but in other areas it should not; (3 There are some ways to bridge or close the negative gap; (4 There exists hybrid career opportunities to become professionals that work both as an academician and a practitioner; (5 This new breed of hybrid professionals has a huge potential to bridge the bad theory-practice gap.

  15. Review on the Construction Technology of Railway Jacking Culvert%铁路顶进涵施工技术综述

    Institute of Scientific and Technical Information of China (English)

    张锐祺

    2015-01-01

    本文以青阜线增建二线工程为例,简单介绍了工程的框架涵预制,对便梁施工的防护以及铁路工程的涵体顶进等施工工序进行了相关分析和介绍,并提出一些控制质量措施和安全措施,对有关铁路营业线框架涵顶进的施工技术有很好的指导意义,为相关的铁路工作人员提供了一定的参考。%in this paper, through specific examples on the top of the railway into the culvert construction technology further explanation and analysis, With Qing Fu line additional second-line project as an example, a brief introduc⁃tion on theframe culvert prefabrication of the project is made, the protection ofbeam construction and culvert jack⁃ingand other construction processes ofrailway engineering are carried out with relative analysis and introduction, and put somequality control measures and safety measures are proposed, which has good guiding significance for related⁃construction technology ofrailway business line frame culvert, and provides certain referencefor related railwaystaff.

  16. Diode-quad bridge for reactive transducers and FM discriminators

    Science.gov (United States)

    Harrison, D. R.; Dimeff, J.

    1972-01-01

    Diode-quad bridge circuit was developed for use with pressure-sensitive capacitive transducers, liquid-level measuring devices, proximity deflection sensors, and inductive displacement sensors. It may also be used as FM discriminator and as universal impedance bridge.

  17. 21 CFR 872.3770 - Temporary crown and bridge resin.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Temporary crown and bridge resin. 872.3770 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3770 Temporary crown and bridge resin. (a) Identification. A temporary crown and bridge resin is a device composed of a material, such...

  18. Resin-Bonded Bridges in vitro and in vivo

    NARCIS (Netherlands)

    Veen, Johannes Hilbrandt van der

    1988-01-01

    In this thesis in vitro and in vivo studies on the clinical application of resin-bonded bridges are described and discussed. The development of different types of resin-bonded bridges is described in chapter 1. The bridges are often made by boding a cast metal retainer fitted with and artificial too

  19. Bridging the Gap: Linking Simulation and Testing

    Energy Technology Data Exchange (ETDEWEB)

    Krajewski, Paul E.; Carsley, John; Stoudt, Mark R.; Hovanski, Yuri

    2012-09-01

    The Materials Genome Initiative (MGI) which is a key enabler for the Advanced Manufacturing Partnership, announced in 2011 by U.S. President Barack Obama, was established to accelerate the development and deployment of advanced materials. The MGI is driven by the need to "bridge the gap" between (I) experimental results and computational analysis to enable the rapid development and validation of new mateirals, and (II) the processes required to convert these materials into useable goods.

  20. Bridging the Divide between Science and Journalism

    OpenAIRE

    Marincola Francesco M; Van Eperen Laura; Strohm Jennifer

    2010-01-01

    Abstract There are countless reasons nearly every scientist should learn how to communicate effectively with the media, including increased understanding of critical research findings to attract or sustain funding and build new professional partnerships that will further propel forward research. But where do scientists begin? Bridging the Divide between Science and Journalism offers practical tips for any scientist looking to work with the media. Given the traditional and internet-based sourc...

  1. Hydraulic bridges in unsaturated coarse granular media: Influence of bridge size and conductivity on flow through clasts

    Science.gov (United States)

    Jayakody, Jeevan A.; Nicholl, Michael J.

    2016-10-01

    Unsaturated flow in coarse granular media must pass through hydraulic bridges (e.g., pendular water, porous connections) that form a physical connection between adjoining clasts. Previous studies suggest that volumetric flow through a porous clast (Q) will be linearly dependent on the cross-sectional area of the hydraulic bridges, and understate the importance of bridge conductivity. Numerical simulations were performed to explore steady-state flow through a spherical clast with identical bridges located at the top and bottom. The cross-sectional area of the bridges relative to that of the clast (Ar) was varied across six orders of magnitude. The ratio of hydraulic conductivity between bridges and clasts (Kb/Kc) was varied across 12 orders of magnitude to consider resistive, neutral, and conductive bridges. Results show that hydraulic bridges place a primary control on both Q and flux distribution within the clast. For neutral and conductive bridges (Kb/Kc ≥1), Ar is the dominant factor in determining Q, while Kb/Kc is the primary control for resistive bridges (Kb/Kc < 1). For all bridges, Q shows a non-linear dependency on both Ar and Kb/Kc. The intra-clast flow distribution shifts outwards as Ar increases. Conductive bridges promote this process and resistive bridges impede it.

  2. Bridge Inspections and Being an ERC

    OpenAIRE

    Hoernschemeyer, Keith; Miller, Jessica

    2015-01-01

    This presentation will discuss recent changes to the County Bridge Inspection Program from the perspective of both the FHWA and INDOT. We will also discuss the responsibilities of the local public agency’s (LPA’s) employee in responsible charge (ERC) with respect to managing this program. As this course is a yearly requirement, all county ERCs are encouraged to attend. Pre-registering is strongly encouraged by e-mailing your contact information to .

  3. Excitation of Arch and Suspension Bridges by Subwires

    Directory of Open Access Journals (Sweden)

    Noriaki Hiwatashi

    1993-01-01

    Full Text Available A force generation method using a subwire for arch and suspension bridges is proposed. The subwire is connected to the arch or the cable of the bridge through rollers. The uniform force produced by pulling and releasing the pretensioned subwires acts on the bridge as an externalforce. A new device called “the resonance force generator” is also developed to excite the bridges by applying a small force. To verify the proposed concept, a stress ribbon bridge was excited with the resonance force generator.

  4. Excitation of Arch and Suspension Bridges by Subwires

    OpenAIRE

    Noriaki Hiwatashi; Yoji Mizuta; Yutaka Ishihara; Itio Hirai

    1993-01-01

    A force generation method using a subwire for arch and suspension bridges is proposed. The subwire is connected to the arch or the cable of the bridge through rollers. The uniform force produced by pulling and releasing the pretensioned subwires acts on the bridge as an externalforce. A new device called “the resonance force generator” is also developed to excite the bridges by applying a small force. To verify the proposed concept, a stress ribbon bridge was excited with the resonance force ...

  5. Jointless and Smoother Bridges: Behavior and Design of Piles

    OpenAIRE

    Frosch, Robert J; Chovichien, Voraniti; Durbin, Katrinna; Fedroff, David

    2006-01-01

    Integral abutment bridges have been used in the United States for decades. By eliminating expensive expansion joints, the piles supporting the end bent accommodate the total thermal movement of the bridge. Currently, integral bridges are designed based upon experience, and a rational design specification has not been developed. Furthermore, the interaction of the abutment, pile, and soil remains uncertain. A better understanding regarding the behavior of this system is needed. The objective o...

  6. Bridging Music and Psychoanalytic Therapy

    Directory of Open Access Journals (Sweden)

    Deborah Salmon

    2008-03-01

    Full Text Available The author draws upon theory, training and clinical experience in palliative care music therapy and verbal psychoanalytic therapy. Elements common to both music and psychoanalytic therapy are explored; the centrality of listening, the boundaries and fluidity of time, the importance of containment and expression of affect, the capacity to facilitate mourning, and the inherent creativity of each. Contributions from analytic music therapy are considered. Two case vignettes are presented; the first integrates psychoanalytic thinking into music therapy work with a dying woman; the second, from verbal psychotherapy practise, illustrates mourning being facilitated by the spontaneous use of a song., The question of training music therapists to do depth work using psychoanalytic concepts is raised, particularly in respect to the use of words and recognition of transference and countertransference phenomena. Finally, the author reflects on her experience of music therapy and psychotherapy work each enriching and deepening the other.

  7. Bridging experiments, models and simulations

    DEFF Research Database (Denmark)

    Carusi, Annamaria; Burrage, Kevin; Rodríguez, Blanca

    2012-01-01

    study aims at informing strategies for validation by elucidating the complex interrelations among experiments, models, and simulations in cardiac electrophysiology. We describe the processes, data, and knowledge involved in the construction of whole ventricular multiscale models of cardiac...

  8. Bridging Animal and Human Models

    OpenAIRE

    Barkley-Levenson, Amanda M.; Crabbe, John C.

    2012-01-01

    Genetics play an important role in the development and course of alcohol abuse, and understanding genetic contributions to this disorder may lead to improved preventative and therapeutic strategies in the future. Studies both in humans and in animal models are necessary to fully understand the neurobiology of alcoholism from the molecular to the cognitive level. By dissecting the complex facets of alcoholism into discrete, well-defined phenotypes that are measurable in both human populations ...

  9. Bridging classical and quantum mechanics

    Science.gov (United States)

    Haddad, D.; Seifert, F.; Chao, L. S.; Li, S.; Newell, D. B.; Pratt, J. R.; Williams, C.; Schlamminger, S.

    2016-10-01

    Using a watt balance and a frequency comb, a mass-energy equivalence is derived. The watt balance compares mechanical power measured in terms of the meter, the second, and the kilogram to electrical power measured in terms of the volt and the ohm. A direct link between mechanical action and the Planck constant is established by the practical realization of the electrical units derived from the Josephson and the quantum Hall effects. By using frequency combs to measure velocities and acceleration of gravity, the unit of mass can be realized from a set of three defining constants: the Planck constant h, the speed of light c, and the hyperfine splitting frequency of 133Cs.

  10. Bridging intuitive and analytical thinking

    DEFF Research Database (Denmark)

    Ejersbo, Lisser Rye; Leron, Uri; Arcavi, Abraham

    2014-01-01

    of thinking, much of it under the umbrella of the so-called Dual-Process Theory, where the intuitive and analytical modes has been called System 1 and System 2, respectively. (Gilovich et al, 2002; Kahnemann, 2002; Kahneman, 2011, Evans & Frankish, 2009.) Much of the relevant research in psychology...

  11. Bridging Corporate and Organizational Communication

    DEFF Research Database (Denmark)

    Christensen, Lars Thøger; Cornelissen, Joep

    2011-01-01

    organizational communication as well. We provide a formative and critical review of research on corporate communication as a platform for highlighting crucial intersections with select research traditions in organizational communication to argue for a greater integration between these two areas of research......The theory and practice of corporate communication is usually driven by other disciplinary concerns than the field of organizational communication. However, its particular mind-set focusing on wholeness and consistency in corporate messages increasingly influence the domain of contemporary....... Following this review, we relax the assumptions underlying traditional corporate communication research and show how these dimensions interact in organizational and communication analysis, thus, demonstrating the potential for a greater cross-fertilization between the two areas of research. This cross...

  12. Field Tests and Simulation of Lion-Head River Bridge

    Directory of Open Access Journals (Sweden)

    Yao-Min Fang

    2007-01-01

    Full Text Available Lion-Head River Bridge is a twin bridge in parallel position. The east-bounded was designed and constructed as a traditional prestress concrete box girder bridge with pot bearings; and the west-bounded was installed with seismic isolation devices of lead rubber bearings. The behavior of the isolated bridge is compared with that of the traditional bridge through several field tests including the ambient vibration test, the force vibration test induced by shakers, the free vibration test induced by a push and fast release system, and the truck test. The bridges suffered from various extents of damage due to the Chi-Chi and the Chi-I earthquakes of great strength during the construction and had been retrofitted. The damage was reflected by the change of the bridges' natural frequencies obtained from the ambient vibration tests. The models of the two bridges are simulated by the finite element method based on the original design drawings. Soil-structure interaction was also scrutinized in this study. The simulation was then modified based on the results from the field tests. Dynamic parameters of bridges are identified and compared with those from theoretical simulation. The efficiency is also verified to be better for an isolated bridge.

  13. Case studies on construction works of short span bridges in Kenya; Kenya kyowakoku ni okeru chusho kyoryo koji no jirei

    Energy Technology Data Exchange (ETDEWEB)

    Kurino, S. [Honshu-Shikoku Bridge Authority, Tokyo (Japan)

    1998-01-01

    In the Republic of Kenya, problems are how to build bridges over small rivers, not big rivers, and what bridge types to choose for reduction in cost. Concrete bridges under the direct control of the Government construction office are 15m at the longest, and they are directly founded on the hard basement after a little excavation. In formulating construction plans, it is necessary to take climate into account, such that there is but a small amount of precipitation and that it concentrates in the rainy season. The first stage of bridge building involves the construction of low-cost structures which enable river-crossing except in the rainy season. This first-stage concept is worth deliberation when it is known that there are semiarid regions where river-crossing is prohibited due to high water levels in the rainy season but for approximately two weeks a year. In the second stage, permanent structures are required, serviceable even in the high water level season. In the third stage, it is necessary to construct bridges conforming to the road assuring excellent trafficability. For reduction in the cost of small bridge construction, drift types, culvert types, and temporary bridges like Bailey bridges are important choices. 2 refs., 12 figs.

  14. Bridges analysis, design, structural health monitoring, and rehabilitation

    CERN Document Server

    Bakht, Baidar

    2015-01-01

    This book offers a valuable guide for practicing bridge engineers and graduate students in structural engineering; its main purpose is to present the latest concepts in bridge engineering in fairly easy-to-follow terms. The book provides details of easy-to-use computer programs for: ·      Analysing slab-on-girder bridges for live load distribution. ·      Analysing slab and other solid bridge components for live load distribution. ·      Analysing and designing concrete deck slab overhangs of girder bridges under vehicular loads. ·      Determining the failure loads of concrete deck slabs of girder bridges under concentrated wheel loads. In addition, the book includes extensive chapters dealing with the design of wood bridges and soil-steel bridges. Further, a unique chapter on structural health monitoring (SHM) will help bridge engineers determine the actual load carrying capacities of bridges, as opposed to their perceived analytical capacities. The chapter addressing structures...

  15. Construction and control technology of the main bridge superstructure of Sutong Bridge

    Institute of Scientific and Technical Information of China (English)

    Zhang Hong; Luo Chenbin; Zhang Yongtao; You Xinpeng

    2009-01-01

    The Sutong Yangtze River Bridge (short as Sutong Bridge) is now the largest span cable-stayed bridge in the world. The construction of the superstructure of the middle bridge covered several stages including erection of the big block girders for the side span, assistant span and tower area, erection of standard girders and closure of the middle span. The big block girders were hoisted by a floating crane, and the standard girders were hoisted by a double crane system on the deck. The pushing assistant method was adopted for the middle span closure construction. Furthermore, key technologies and innovative methods used in the processes of girder erection and cable assemblage in all stages were expatiated systematically. An all-stage self- adaptive geometry control method was used in the construction process. By accurately controlling the unstressed dimensions and shape of all structural components in each step, and realization that the control system and the controlled system adapt to each other, the goal was to make control of the final line shape and inner force of the bridge structure achievable. Two solutions, including GPS based and total station based dynamic geometry monitoring systems, were used to resolve the measure problem under the wide-range of wind-induced vibrations in the long cantilever state. Finally, research on the wind-induced vibration of the superstructure during the construction period was executed. Buffeting response analysis to the longest single and double cantilever states were carried out. The analysis and evaluation of wind resistance safety of the main girders under the longest single cantilever state was made, and corresponding wind resistance measures were suggested. The as-built geometric error and cable force error were controlled in a required design range, and this whole technological achievement can be a benchmark for construction of other large span cable-stayed bridges in the future.

  16. Bridging physics and biology teaching through modeling

    Science.gov (United States)

    Hoskinson, Anne-Marie; Couch, Brian A.; Zwickl, Benjamin M.; Hinko, Kathleen A.; Caballero, Marcos D.

    2014-05-01

    As the frontiers of biology become increasingly interdisciplinary, the physics education community has engaged in ongoing efforts to make physics classes more relevant to life science majors. These efforts are complicated by the many apparent differences between these fields, including the types of systems that each studies, the behavior of those systems, the kinds of measurements that each makes, and the role of mathematics in each field. Nonetheless, physics and biology are both sciences that rely on observations and measurements to construct models of the natural world. In this article, we propose that efforts to bridge the teaching of these two disciplines must emphasize shared scientific practices, particularly scientific modeling. We define modeling using language common to both disciplines and highlight how an understanding of the modeling process can help reconcile apparent differences between the teaching of physics and biology. We elaborate on how models can be used for explanatory, predictive, and functional purposes and present common models from each discipline demonstrating key modeling principles. By framing interdisciplinary teaching in the context of modeling, we aim to bridge physics and biology teaching and to equip students with modeling competencies applicable in any scientific discipline.

  17. Markovian Bridges: Weak continuity and pathwise constructions

    OpenAIRE

    Chaumont, Loïc; Uribe Bravo, Gerónimo

    2009-01-01

    A Markovian bridge is a probability measure taken from a disintegration of the law of an initial part of the path of a Markov process given its terminal value. As such, Markovian bridges admit a natural parameterization in terms of the state space of the process. In the context of Feller processes with continuous transition densities, we construct by weak convergence considerations the only versions of Markovian bridges which are weakly continuous with respect to their parameter. We use this ...

  18. Myocardial bridges: morphological and functional aspects.

    OpenAIRE

    A.G. Ferreira; Trotter, S E; König, B; Décourt, L V; Fox, K; Olsen, E G

    1991-01-01

    OBJECTIVE--To assess the arrangement of myocardial bridges. DESIGN--A necropsy study of 90 consecutive hearts (56 male, 34 female). RESULTS--Myocardial bridges, either single or multiple, were seen in 50 (55.6%) of the 90 hearts. The left anterior descending artery was the most commonly affected artery. Thirty five of the 50 hearts which contained in total 41 muscle bridges were dissected further with a magnifying glass. Two different types of muscle bridges could be identified. Thirty one of...

  19. Electron Transfer rate between a electrode and a bridged redox

    OpenAIRE

    Cruz, A. V. B.; Mishra, A. K.; Schmickler, W.

    2009-01-01

    We derive an explict bias dependent expression for electron transfer reaction rate from a solvated redox to a electrode through a bridged molecule of arbitrary length. The interaction of the solvated redox with the solvent is modelled as a classical harmonic oscillator bath. The effect of competing process, namely resonance tunneling between redox and bridge and the solvation of the redox is investigated. Plots were produced for the case of 5 atom bridge. Our analysis shows that for certain s...

  20. Measurement evaluation and FEM simulation of bridge dynamics

    OpenAIRE

    Andersson, Andreas; Malm, Richard

    2004-01-01

    The aim of this thesis is to analyse the effects of train induced vibrations in a steel Langer beam bridge. A case study of a bridge over the river Ljungan in Ånge has been made by analysing measurements and comparing the results with a finite element model in ABAQUS. The critical details of the bridge are the hangers that are connected to the arches and the main beams. A stabilising system has been made in order to reduce the vibrations which would lead to increased life length of the bridge...

  1. Bridging Innovation and Curriculum in Higher Education

    DEFF Research Database (Denmark)

    Zhang, Fenzhi; Kolmos, Anette; Du, Xiangyun

    2010-01-01

    As innovation is seen as a key factor in economic competitiveness, graduates who can contribute to and participate in innovation are in great need.. Higher education is confronted with the demands that the curriculum practice and learning environments should facilitate innovation and competences...... for innovation. Problem and project based learning has been seen as a strategy for renewing the teaching practice and the learning environment by integrating the competence demands of the curriculum and of work life during the process of education. However, the integrations of innovation into curriculum...... are minor in the problem and project based learning (PBL) literature. Based on theoretical reflections and practical cases in Aalborg University (Denmark), this article presents the basis of PBL knowledge and curriculum conceptualization, and explores a case experience which bridges innovation and PBL...

  2. Experimental and Analytical Investigations of Piles and Abutments of Integral Bridges

    OpenAIRE

    Arsoy, Sami

    2000-01-01

    Bridges without expansion joints are called "integral bridges." Eliminating joints from bridges crates concerns for the piles and the abutments of integral bridges because the abutments and the piles are subjected to temperature-induced cyclic lateral loads. As temperatures change daily and seasonally, the lengths of integral bridges increase and decrease, pushing the abutment against the approach fill and pulling it away. As a result the bridge superstructure, the abutment, the approach f...

  3. Bridging Physics and Biology Teaching through Modeling

    CERN Document Server

    Hoskinson, Anne-Marie; Zwickl, Benjamin M; Hinko, Kathleen; Caballero, Marcos D

    2013-01-01

    As the frontiers of biology become increasingly interdisciplinary, the physics education community has engaged in ongoing efforts to make physics classes more relevant to life sciences majors. These efforts are complicated by the many apparent differences between these fields, including the types of systems that each studies, the behavior of those systems, the kinds of measurements that each makes, and the role of mathematics in each field. Nonetheless, physics and biology are both fundamental sciences that rely on observations and measurements to construct models of the natural world. In the present theoretical article, we propose that efforts to bridge the teaching of these two disciplines must emphasize shared scientific practices, particularly scientific modeling. We define modeling using language common to both disciplines and highlight how an understanding of the modeling process can help reconcile apparent differences between physics and biology. We elaborate how models can be used for explanatory, pre...

  4. GOOD HEALTH AND THE BRIDGING OF STRUCTURAL HOLES.

    Science.gov (United States)

    Cornwell, Benjamin

    2009-01-01

    Bridges that span structural holes are often explained in terms of the entrepreneurial personalities or rational motivations of brokers, or structural processes that lead to the intersection of social foci. I argue that the existence and use of bridges in interpersonal networks also depends on individuals' health. Poor health may make it more difficult to withstand the pressures and to execute some of the common tasks associated with bridging (e.g., brokerage). I examine this possibility using egocentric network data on over 2,500 older adults drawn from the recent National Social Life, Health, and Aging Project (NSHAP). Multivariate regression analyses show that both cognitive and functional health are significantly positively associated with bridging, net of sociodemographic and life-course controls. The relationship between functional (kinesthetic) health and bridging appears to be partially mediated by network composition, as older adults who have poorer functional health also tend to have networks that are richer in strong ties. Several potential mediation mechanisms are discussed. Cognitive function remains significantly associated with bridging net of network composition, suggesting that the inherent challenges of maintaining bridging positions may be more difficult to cope with for those who have cognitive impairments than for those who have functional impairments such as limited mobility. An alternative explanation is that cognitively impaired individuals have more difficulty recognizing (and thus strategically using) bridges in their networks. Theoretical implications and possibilities for future research are discussed. PMID:20046998

  5. Vibration characteristics and damage detection in a suspension bridge

    Science.gov (United States)

    Wickramasinghe, Wasanthi R.; Thambiratnam, David P.; Chan, Tommy H. T.; Nguyen, Theanh

    2016-08-01

    Suspension bridges are flexible and vibration sensitive structures that exhibit complex and multi-modal vibration. Due to this, the usual vibration based methods could face a challenge when used for damage detection in these structures. This paper develops and applies a mode shape component specific damage index (DI) to detect and locate damage in a suspension bridge with pre-tensioned cables. This is important as suspension bridges are large structures and damage in them during their long service lives could easily go un-noticed. The capability of the proposed vibration based DI is demonstrated through its application to detect and locate single and multiple damages with varied locations and severity in the cables of the suspension bridge. The outcome of this research will enhance the safety and performance of these bridges which play an important role in the transport network.

  6. Comparison of Ferry Boat and Highway Bridge Energy Use

    Directory of Open Access Journals (Sweden)

    Wayne D. Cottrell

    2011-01-01

    Full Text Available Passenger ferries serve a variety of transport needs in the U.S., such as providing vital links across bodies of water, and supplementing highway bridges. In some cases in which there is a ferry connection but no bridge, a bridge would be impractical; in other cases, a bridge might be feasible. The paper compares the energy consumption of ferries and motor vehicles on bridges, to determine which link is more fuel efficient. One finding is that limited data are available on ferry boat fuel consumption: despite there being 208 ferry boat operators in the U.S. as of 2008, only eight were providing energy use data to the National Transit Database. Examinations of three of the systems found that the passenger-MPG of the ferries ranged from 2.61 to 14.00 (1.11 to 5.95 km/L, while that of the motor vehicles on adjacent highway bridge connections ranged from 25.34 to 32.45 (10.77 to 13.79 km/L. Data from the eight systems are used to develop a ferry MPG model. The model is used to show that the Ryer Island and Charles Hall Ferries are less fuel efficient than hypothetical bridges in those locations. The fuel efficiencies and consumptions of the ferries would equal those of motor vehicles on the bridges, however, if smaller vessels were used, and if the frequency of service was reduced.

  7. Use of UHPC in Bridge Structures: Material Modeling and Design

    Directory of Open Access Journals (Sweden)

    Oguz Gunes

    2012-01-01

    Full Text Available Ultra-high-performance concrete (UHPC is a promising new class of concrete material that is likely to make a significant contribution to addressing the challenges associated with the load capacity, durability, sustainability, economy, and environmental impact of concrete bridge infrastructures. This paper focuses on the material modeling of UHPC and design of bridge girders made of UHPC. A two-phase model used for modeling the behavior of UHPC was briefly discussed, and the model was implemented in a preliminary design case study. Based on the implemented design and the reported use of UHPC in bridge applications, the advantages, limitations, and future prospects of UHPC bridges were discussed, highlighting the need for innovative research and design to make optimum use of the favorable properties of the material in bridge structures.

  8. Solving Topological and Geometrical Constraints in Bridge Feature Model

    Institute of Scientific and Technical Information of China (English)

    PENG Weibing; SONG Liangliang; PAN Guoshuai

    2008-01-01

    The capacity that computer can solve more complex design problem was gradually increased.Bridge designs need a breakthrough in the current development limitations, and then become more intelli-gent and integrated. This paper proposes a new parametric and feature-based computer aided design (CAD) models which can represent families of bridge objects, includes knowledge representation, three-dimensional geometric topology relationships. The realization of a family member is found by solving first the geometdc constraints, and then the topological constraints. From the geometric solution, constraint equations are constructed. Topology solution is developed by feature dependencies graph between bridge objects. Finally, feature parameters are proposed to drive bridge design with feature parameters. Results from our implementation show that the method can help to facilitate bridge design.

  9. Floating and flying ferrofluid bridges induced by external magnetic fields

    Science.gov (United States)

    Ma, Rongchao; Zhou, Yixin; Liu, Jing

    2015-04-01

    A ferrofluid is a mixture that exhibits both magnetism and fluidity. This merit enables the ferrofluid to be used in a wide variety of areas. Here we show that a floating ferrofluid bridge can be induced between two separated boards under a balanced external magnetic field generated by two magnets, while a flying ferrofluid bridge can be induced under an unbalanced external magnetic field generated by only one magnet. The mechanisms of the ferrofluid bridges were discussed and the corresponding mathematical equations were also established to describe the interacting magnetic force between the ferro particles inside the ferrofluid. This work answered a basic question that, except for the well-known floating water bridges that are related to electricity, one can also build up a liquid bridge that is related to magnetism.

  10. Analysis of resonance mechanism and conditions of train bridge system

    Science.gov (United States)

    Xia, H.; Zhang, N.; Guo, W. W.

    2006-11-01

    In this paper, the resonance mechanism and conditions of train-bridge system are investigated through theoretical derivations, numerical simulations and experimental data analyses. The resonant responses of the bridge induced by moving trains are classified into three types according to different resonance mechanisms: the first is related to the periodical actions of moving load series of the vertical weights, lateral centrifugal and wind forces of vehicles; the second is induced by the loading rate of moving load series of vehicles; the third is owing to the periodically loading of the swing forces of the train vehicles excited by track irregularities and wheel hunting movements. The vehicle resonance is induced by the periodical action of regular arrangement of bridge spans and their deflections. The resonant conditions are proposed and the corresponding resonant train speeds are determined. The application scopes of resonance conditions are discussed. The resonance of the train-bridge system is affected by the span, total length, lateral and vertical stiffness of the bridge, the compositions of the train, and the axle arrangements and natural frequencies of the vehicles. The resonant train speeds for some bridges are estimated and are compared with the critical train speeds obtained from the dynamic simulation of train-bridge interaction model or from the field measurements.

  11. Technology transfer — bridging space and society

    Science.gov (United States)

    Students of Technology Transfer Design Project Team (ISU Summer Session 1997)

    Strategies, policies and methods by which technologies can be 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 be 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.

  12. Technology and organization in bridge construction by using movable scaffolding system

    OpenAIRE

    Rosa, Simon

    2008-01-01

    The thesis presents construction of a bridge presented on a case study of the Šumljak bridge. The bridge is located on the motorway section Razdrto-Vipava characterized by an extremely complexe morphology and geology, which makes the bridge location one of the most demanding parts to be bridged within the Slovenian National Highway Construction Programme. The "S" shaped bridge axis dictates the use of the field by field construction method on mechanized movable scaffolding. This technology en...

  13. Model bridging chimera state and explosive synchronization

    Science.gov (United States)

    Zhang, Xiyun; Bi, Hongjie; Guan, Shuguang; Liu, Jinming; Liu, Zonghua

    2016-07-01

    Global synchronization and partial synchronization are the two distinctive forms of synchronization in coupled oscillators and have been well studied in recent decades. Recent attention on synchronization is focused on the chimera state (CS) and explosive synchronization (ES), but little attention has been paid to their relationship. Here we study this topic by presenting a model to bridge these two phenomena, which consists of two groups of coupled oscillators, and its coupling strength is adaptively controlled by a local order parameter. We find that this model displays either CS or ES in two limits. In between the two limits, this model exhibits both CS and ES, where CS can be observed for a fixed coupling strength and ES appears when the coupling is increased adiabatically. Moreover, we show both theoretically and numerically that there are a variety of CS basin patterns for the case of identical oscillators, depending on the distributions of both the initial order parameters and the initial average phases. This model suggests a way to easily observe CS, in contrast to other models having some (weak or strong) dependence on initial conditions.

  14. Bridging the divide between science and journalism.

    Science.gov (United States)

    Van Eperen, Laura; Marincola, Francesco M; Strohm, Jennifer

    2010-01-01

    There are countless reasons nearly every scientist should learn how to communicate effectively with the media, including increased understanding of critical research findings to attract or sustain funding and build new professional partnerships that will further propel forward research. But where do scientists begin? Bridging the Divide between Science and Journalism offers practical tips for any scientist looking to work with the media.Given the traditional and internet-based sources for medical research and healthcare-related news now available, it is imperative that scientists know how to communicate their latest findings through the appropriate channels. The credible media channels are managed by working journalists, so learning how to package vast, technical research in a form that is appetizing and "bite-sized" in order to get their attention, is an art. Reducing years of research into a headline can be extremely difficult and certainly doesn't come naturally to every scientist, so this article provides suggestions on how to work with the media to communicate your findings. PMID:20219123

  15. Bridging the Divide between Science and Journalism

    Directory of Open Access Journals (Sweden)

    Marincola Francesco M

    2010-03-01

    Full Text Available Abstract There are countless reasons nearly every scientist should learn how to communicate effectively with the media, including increased understanding of critical research findings to attract or sustain funding and build new professional partnerships that will further propel forward research. But where do scientists begin? Bridging the Divide between Science and Journalism offers practical tips for any scientist looking to work with the media. Given the traditional and internet-based sources for medical research and healthcare-related news now available, it is imperative that scientists know how to communicate their latest findings through the appropriate channels. The credible media channels are managed by working journalists, so learning how to package vast, technical research in a form that is appetizing and "bite-sized" in order to get their attention, is an art. Reducing years of research into a headline can be extremely difficult and certainly doesn't come naturally to every scientist, so this article provides suggestions on how to work with the media to communicate your findings.

  16. Stargate GTM: Bridging Descriptor and Activity Spaces.

    Science.gov (United States)

    Gaspar, Héléna A; Baskin, Igor I; Marcou, Gilles; Horvath, Dragos; Varnek, Alexandre

    2015-11-23

    Predicting the activity profile of a molecule or discovering structures possessing a specific activity profile are two important goals in chemoinformatics, which could be achieved by bridging activity and molecular descriptor spaces. In this paper, we introduce the "Stargate" version of the Generative Topographic Mapping approach (S-GTM) in which two different multidimensional spaces (e.g., structural descriptor space and activity space) are linked through a common 2D latent space. In the S-GTM algorithm, the manifolds are trained simultaneously in two initial spaces using the probabilities in the 2D latent space calculated as a weighted geometric mean of probability distributions in both spaces. S-GTM has the following interesting features: (1) activities are involved during the training procedure; therefore, the method is supervised, unlike conventional GTM; (2) using molecular descriptors of a given compound as input, the model predicts a whole activity profile, and (3) using an activity profile as input, areas populated by relevant chemical structures can be detected. To assess the performance of S-GTM prediction models, a descriptor space (ISIDA descriptors) of a set of 1325 GPCR ligands was related to a B-dimensional (B = 1 or 8) activity space corresponding to pKi values for eight different targets. S-GTM outperforms conventional GTM for individual activities and performs similarly to the Lasso multitask learning algorithm, although it is still slightly less accurate than the Random Forest method.

  17. Definition and segmentation of BioMedBridges stakeholders

    OpenAIRE

    Brooksbank, Cath; Alfarez, Deborah

    2014-01-01

    The success of BioMedBridges will depend on outreach and inreach to diverse groups of stakeholders. This deliverable report describes the use of a survey to define the broad stakeholder groups with whom BioMedBridges needs to engage, and to collect information on how the individual ESFRI-BMS RIs currently engage with these groups. We wanted to know who these stakeholders are, how the RIs are currently engaging with them, and what aspects of BioMedBridges the respondents felt we should be cons...

  18. Myocardial bridges: their clinical implications and prognostic signs

    International Nuclear Information System (INIS)

    Among 980 consecutive selective coronary angiograms performed, nine patients had myocardial bridges of the left anterior descending (LAD) coronary artery. The overall prevalence of myocardial bridge was 0.92%. Among these patients, three patients had coronary artery disease, while six cases were isolated myocardial muscle bridges. With respect to functional abnormality, three had grade III milking effect, three had grade II and three had grade I milking effect. The indications for coronary angiograms were typical chest pain in seven cases and a typical chest pain in two cases. Their clinical and laboratory investigations are presented with literature review. (author)

  19. Practice of One Health approaches: Bridges and barriers in Tanzania

    OpenAIRE

    Kim A. Kayunze; Angwara Kiwara; Eligius Lyamuya; Dominic M. Kambarage; Jonathan Rushton; Richard Coker; Richard Kock

    2014-01-01

    The practice of one health approaches in human and animal health programmes is influenced by type and scope of bridges and barriers for partnerships. It was thus essential to evaluate the nature and scope of collaborative arrangements among human, animal, and wildlife health experts in dealing with health challenges which demand inter-sectoral partnership. The nature of collaborative arrangement was assessed, and the respective bridges and barriers over a period of 12 months (July 20011 to Ju...

  20. Bridging the Gap between Instructional Design and Double Loop Learning

    NARCIS (Netherlands)

    Spoelstra, Howard; Rusman, Ellen; Van Bruggen, Jan; Koper, Rob; Matera, Maristella

    2008-01-01

    Spoelstra, H., Rusman, E., Van Bruggen, J., Koper, R., & Matera, M. (2008). Bridging the Gap Between Instructional Design and Double-Loop Learning. International Journal of Web-Based Learning and Teaching Technologies, 3(1), 79-89.

  1. Optimal, Generic Planning of Maintenance and Inspection of Steel Bridges

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Faber, M.H.

    2002-01-01

    Fatigue damage is an important deterioration mechanism for steel bridges. This paper describes a simplified and generic approach for reliability and risk based inspection planning of fatigue sensitive structural details. Fatigue sensitive details are categorized according to their loading charact...

  2. Live-Load Testing and Finite-Element Analysis of a Steel Cantilever Deck Arched Pratt Truss Bridge for the Long-Term Bridge Performance Program

    OpenAIRE

    Laurendeau, Matthew P.

    2011-01-01

    The Long Term Bridge Performance (LTBP) program is an organization within the Federal Highway Administration that inspects, tests, analyzes, and observes, for an extended period of time, a variety of bridge types throughout the United States. Part of the program includes periodic testing of select bridges of a span of 20 years. The Kettle River Bridge located outside of Sandstone, Minnesota was selected for study due to its unique design. The Kettle River Bridge is a historical steel can...

  3. Dynamics and stability of a vertical water bridge

    CERN Document Server

    Namin, Reza Montazeri

    2013-01-01

    A vertical connection of water is formed when a high voltage electrode is dipped in and pulled out of a container of deionized water. We considered the formation, stability and dynamical characteristics of this vertical water bridge. For the first time in this field, we observed instabilities in the bridge that led to an oscillatory behaviour which is categorized in three dynamical regimes and supplied explanations on the physics behind these varied motions. We report the formation of macroscopic droplets during this motion, which their dynamics revealed that they are electrically charged. In some cases the droplets would be levitating when the electric force opposes the gravity. Also the steady bridge is thoroughly studied regarding its geometry and a set of quantitative data is presented using dimensionless numbers, which brings the possibility of direct quantitative comparison between theory and experiments. Our results shed light on the physics behind this phenomenon and the horizontal water bridge, which...

  4. Bridging the gap between GCMs and CRMs

    Science.gov (United States)

    Silvers, Levi; Stevens, Bjorn; Hohenegger, Cathy

    2014-05-01

    Bridging the gap between GCMs and CRMs Radiative Convective Equilibrium (RCE) has proven to be a useful framework for process studies. In the past there has been little direct overlap of the studies made using General Circulation Models (GCMs), and Cloud Resolving Models (CRMs). GCMs use global or near global domain sizes with resolutions ranging from 300 km to 20 km, while CRMs normally use domains roughly equivalent to a single GCM grid cell and resolutions ranging from 5km to 0.1km. Here we study the atmosphere of a General Circulation Model (GCM) with boundary conditions that approximate Radiative Convective Equilibrium (RCE) across a range of domain sizes (from 45 % of the surface of the Earth to 500x500 km^2) and resolutions of 20 km and 10 km. To that aim we use the newly developed nonhydrostatic, primitive equation model named ICON with horizontally uniform insolation and ozone, no rotation, and a prescribed surface temperature. Comparison of the simulations leads to a better understanding of the mechanisms and assumptions that underlay the parameterizations of GCMs. Climate sensitivity and convective organization are the two physical processes we focus on with this study. Both of these processes are important components of a physical understanding of the Earth system. Convective organization strongly influences the mean state of the atmosphere and the various feedback responses to radiative perturbations. We compare changes in the TOA radiative imbalance which result from prescribed changes in the surface temperature across our simulations. This provides a direct calculation of the various feedback mechanisms. The magnitude of the influence these feedbacks have on a system is commonly diagnosed through the climate sensitivity. We examine the dependence on domain size and parameterization schemes of the convective organization and climate sensitivity. Initial results with two physics parameterization packages indicate that ICON provides a convenient

  5. Re(I) bridged porphyrin dyads, triads and tetrads

    Indian Academy of Sciences (India)

    M Yedukondalu; M Ravikanth

    2011-03-01

    Porphyrin rings containing two meso-pyridyl groups either in cis or trans fashion can be used to construct Re(I) bridged multiporphyrin assemblies. The cis-dipyridyl porphyrins with various porphyrin cores such as N4, N3O, N3S, N2S2 have been used to react with Re(CO)5Cl in THF at refluxing temperature and constructed planar Re(I) bridged porphyrin dyads containing either one type of porphyrin subunit or two types of porphyrin subunits. The trans-dipyridyl porphyrins have been used to construct Re(I) bridged porphyrin squares. The porphyrin dyads have been explored for singlet-singlet energy transfer studies and porphyrin squares have been used for catalysis, chemical sensing, molecular sieving and photocurrent production studies. An overview of synthesis of Re(I) bridged porphyrin dyads, triads and tetrads and their interesting photophysical properties are highlighted in this paper.

  6. Segmental Bridges under Combined Torsion, Bending and Shear

    Institute of Scientific and Technical Information of China (English)

    黄真; 刘西拉

    2003-01-01

    Segmental bridges with unbonded prestressed tendons have some advantages, such as the weather independence and the corrosion protection of prestressing tendons. This paper analyzed the behavior of a prestressed segmental bridge with unbonded tendons under combined loading of torsion, bending and shear. According to the experiment research, a modified skew bending model was developed to calculate the bearing capacity of segmental bridges subjected to combined bending, shear and torsion. The finite element method was used to investigate the deflection behaviors of such structure, also to check the theoretical model. The theoretical and FEM research resuits were compared favorably with the test results from Technical University of Braunschweig, Germany. Finally, suggestion for the design and construction of segmental bridges with external prestressing was made.

  7. The Tacoma Narrows Bridge Collapse on Film and Video

    Science.gov (United States)

    Olson, Don; Hook, Joseph; Doescher, Russell; Wolf, Steven

    2015-11-01

    This month marks the 75th anniversary of the Tacoma Narrows Bridge collapse. During a gale on Nov. 7, 1940, the bridge exhibited remarkable oscillations before collapsing spectacularly (Figs. 1-5). Physicists over the years have spent a great deal of time and energy studying this event. By using open-source analysis tools and digitized footage of the disaster, physics students in both high school and college can continue in this tradition. Students can watch footage of "Galloping Gertie," ask scientific questions about the bridge's collapse, analyze data, and draw conclusions from that analysis. Students should be encouraged to pursue their own investigations, but the question that drove our inquiry was this: "When physics classes watch modern video showing the oscillations and the free fall of the bridge fragments, are these scenes sped up, slowed down, or at the correct speed compared to what was observed by the eyewitnesses on Nov. 7, 1940?"

  8. Fabrication and Visualization of Capillary Bridges in Slit Pore Geometry

    OpenAIRE

    Broesch, David J.; Frechette, Joelle

    2014-01-01

    A procedure for creating and imaging capillary bridges in slit-pore geometry is presented. High aspect ratio hydrophobic pillars are fabricated and functionalized to render their top surfaces hydrophilic. The combination of a physical feature (the pillar) with a chemical boundary (the hydrophilic film on the top of the pillar) provides both a physical and chemical heterogeneity that pins the triple contact line, a necessary feature to create stable long but narrow capillary bridges. The subst...

  9. Bridging history and social psychology: what, how and why.

    Science.gov (United States)

    Glăveanu, Vlad; Yamamoto, Koji

    2012-12-01

    This special issue aims to bridge history and social psychology by bringing together historians and social psychologists in an exercise of reading and learning from each other's work. This interdisciplinary exercise is not only timely but of great importance for both disciplines. Social psychologists can benefit from engaging with historical sources by being able to contextualise their findings and enrich their theoretical models. It is not only that all social and psychological phenomena have a history but this history is very much part of present-day and future developments. On the other hand historians can enhance their analysis of historical sources by drawing upon the conceptual tools developed in social psychology. They can "test" these tools and contribute to their validation and enrichment from completely different perspectives. Most important, as contributions to this special issue amply demonstrate, psychology's "historical turn" has the potential to shed a new light on striking, yet underexplored, similarities between contemporary public spheres and their pre-modern counterparts. This issue thereby calls into question the dichotomy between traditional and de-traditionalized societies-a distinction that lies at the heart of many social psychology accounts of the world we live in. The present editorial will introduce and consider this act of bridging history and social psychology by focusing on three main questions: What is the bridge made of? How can the two disciplines be bridged? and Why we cross this interdisciplinary bridge? In the end a reflection on the future of this collaboration will be offered.

  10. The Research of Application of the Looped Prestressed Tendons with Large Tonnage and Small Radius in the Anchorage Zone of Cable-stayed Bridge Tower%大吨位小半径环向预应力在斜拉桥索塔锚固区中的应用研究

    Institute of Scientific and Technical Information of China (English)

    陈建阳; 徐国平; 刘丽; 朱正群

    2001-01-01

    Nowadays the large tonnage and small radius annular prestress system are applied in the anchorage region of large span cable-stayed bridge construction in our country. The application of this system has been a breakthrough of the Design Specification of Highway Bridge and Culvert. In this article, the application of this system applied in the anchorage region of cable-stayed bridge tower has been probed in close connection with the full-scale model test of the anchorage zone of the Wuhan Junshan Changjiang River Bridge.%目前我国大跨径斜拉桥索塔锚固区开始采用大吨位小半径环向预应力体系,该体系突破了现行《公路桥涵设计规范》的规定。结合武汉军山长江公路大桥索塔锚固区足尺模型试验及张拉工艺模型试验对该预应力体系在斜拉桥索塔锚固区中的应用作了深入的探讨。

  11. Scour and Scour Countermeasures at Bridge Sites

    Institute of Scientific and Technical Information of China (English)

    CHIEW Yee-Meng

    2008-01-01

    This paper examines scour and scour countermeasures at bridge piers and abutments.Abutment scour is by far more complex than its counterpart associated with piers because of the possibility of the presence of a floodplain. Notwithstanding this, the mechanism of scour at both piers and abutments is very similar; moreover, the failure mechanisms associated with both armor-ing and flow-altering countermeasures are not very different. In rivers with a floodplain, abutment scour becomes much more complex. In cases where the abutment ends at or near to the flood-plain, it can initiate bank erosion, which clearly is an important erosion problem that is quite distinct from the customary scour at either an abutment in rivers without a floodplain or a pier. For this rea-son, abutment scour can be very site-specific while pier-scour is more generic in nature. To this end, the ability to identify the type of abutment scour that may form in a particular channel is closely related to an engineer's ability to propose devices for effective scour countermeasure.By summarizing research efforts on using riprap as a pier or abutment countermeasure over the past few decades, this paper highlights the deficiencies of riprap in arresting pier scour. To this end,different failure mechanisms are identified. They are shear failure, winnowing failure, edge failure,bedform-induced failure and bed-degradation induced failure. Each failure mechanism can singly or, more likely, combine to cause the eventual breakdown of the riprap layer. The study shows that a riprap layer is vulnerable to other failure mechanisms even though it is adequately designed against shear failure, rendering it ineffective in arresting scour.

  12. The calculation of noise from railway bridges and viaducts

    OpenAIRE

    Bewes, Oliver Guy

    2005-01-01

    Pandrol Rail Fastenings Limited are a designer and manufacturer of railway rail-fastening systems. As an organisation they have the capability to reduce the noise impact of bridges using resilient track components. They also have a commercial interest in providing such technology. Knowledge of the processes behind bridge noise is important to Pandrol in two ways; to aid the engineers within the organisation in the design of fastening systems and to demonstrate a state-of-the-ar...

  13. Myocardial Bridging

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2016-02-01

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

  14. Fabrication and visualization of capillary bridges in slit pore geometry.

    Science.gov (United States)

    Broesch, David J; Frechette, Joelle

    2014-01-01

    A procedure for creating and imaging capillary bridges in slit-pore geometry is presented. High aspect ratio hydrophobic pillars are fabricated and functionalized to render their top surfaces hydrophilic. The combination of a physical feature (the pillar) with a chemical boundary (the hydrophilic film on the top of the pillar) provides both a physical and chemical heterogeneity that pins the triple contact line, a necessary feature to create stable long but narrow capillary bridges. The substrates with the pillars are attached to glass slides and secured into custom holders. The holders are then mounted onto four axis microstages and positioned such that the pillars are parallel and facing each other. The capillary bridges are formed by introducing a fluid in the gap between the two substrates once the separation between the facing pillars has been reduced to a few hundred micrometers. The custom microstage is then employed to vary the height of the capillary bridge. A CCD camera is positioned to image either the length or the width of the capillary bridge to characterize the morphology of the fluid interface. Pillars with widths down to 250 µm and lengths up to 70 mm were fabricated with this method, leading to capillary bridges with aspect ratios (length/width) of over 100(1). PMID:24457446

  15. Finding Strong Bridges and Strong Articulation Points in Linear Time

    Science.gov (United States)

    Italiano, Giuseppe F.; Laura, Luigi; Santaroni, Federico

    Given a directed graph G, an edge is a strong bridge if its removal increases the number of strongly connected components of G. Similarly, we say that a vertex is a strong articulation point if its removal increases the number of strongly connected components of G. In this paper, we present linear-time algorithms for computing all the strong bridges and all the strong articulation points of directed graphs, solving an open problem posed in [2].

  16. Bridge aerodynamics and aeroelasticity: A comparison of modeling schemes

    Science.gov (United States)

    Wu, Teng; Kareem, Ahsan

    2013-11-01

    Accurate modeling of wind-induced loads on bridge decks is critical to ensure the functionality and survivability of long-span bridges. Over the last few decades, several schemes have emerged to model bridge behavior under winds from an aerodynamic/aeroelastic perspective. A majority of these schemes rely on the quasi-steady (QS) theory. This paper systematically compares and assesses the efficacy of five analytical models available in the literature with a new model presented herein. These models include: QS theory-based model, corrected QS theory-based model, linearized QS theory-based model, semi-empirical linear model, hybrid model, and the proposed modified hybrid model. The ability of these models to capture fluid memory and nonlinear effects either individually or collectively is examined. In addition, their ability to include the effects of turbulence in the approach flow on the bridge behavior is assessed. All models are compared in a consistent manner by utilizing the time domain approach. The underlying role of each model in capturing the physics of bridge behavior under winds is highlighted and the influence of incoming turbulence and its interaction with the bridge deck is examined. A discussion is included that focuses on a number of critical parameters pivotal to the effectiveness of corresponding models.

  17. Bridge Design on Dabaodang-Zhangqiao Section of the Baotou-Xi'an Railway%包西铁路通道大保当至张桥段桥梁设计

    Institute of Scientific and Technical Information of China (English)

    唐英

    2013-01-01

    包西铁路通道大保当至张桥段桥梁长度近101 km,桥址地形地貌复杂,主要存在沙漠地区、煤窑采空区、盐渍土地区及湿陷性黄土地区等不良地质;结合客货共线铁路设计特点,简要介绍桥涵工程概况、桥梁类型的选择、桥梁设计原则、不良地质对桥梁设计的影响;对新结构桥梁设计和重点桥梁也作了简述.%The total length of the bridges on Dabaodang-Zhangqiao section of the Baotou-Xi'an Railway is nearly 101 kilometers,and geological condition at these bridge sites is so complex that it contains lots of desert area,coal mined-out area,saline soil area,collapsible loess area and other unfavorable geologies.Combined with the characteristics of mixed passenger and freight railway,this article introduces project overview of the bridges and culverts,bridge type selection,bridge design principle and the effect of unfavorable geological condition on bridge design.In regard to the designs of new bridge structure and key bridge,the article also gives introduction briefly.

  18. Reduction of Bridge Construction and Maintenance Costs through Coupled Geotechnical and Structural Design of Integral Abutment Bridges

    OpenAIRE

    Frosch, Robert J; Bobet, Antonio; Khasawneh, Yazen

    2014-01-01

    Elimination expansion joints in the superstructure of integral abutment bridges offers the advantage of reducing the initial and life cycle costs of the structure. However, such elimination may have an adverse effect on the displacement demand at the pile-abutment connection and on the earth pressures on the abutment wall due to the thermal expansion/contraction cycles of the bridge. These adverse effects have resulted in regulations that impose restrictions on the maximum length and skew ang...

  19. Light Bridge in a Developing Active Region. I. Observation of Light Bridge and its Dynamic Activity Phenomena

    CERN Document Server

    Toriumi, Shin; Cheung, Mark C M

    2015-01-01

    Light bridges, the bright structures that divide the umbra of sunspots and pores into smaller pieces, are known to produce wide variety of activity events in solar active regions (ARs). It is also known that the light bridges appear in the assembling process of nascent sunspots. The ultimate goal of this series of papers is to reveal the nature of light bridges in developing ARs and the occurrence of activity events associated with the light bridge structures from both observational and numerical approaches. In this first paper, exploiting the observational data obtained by Hinode, IRIS, and Solar Dynamics Observatory (SDO), we investigate the detailed structure of the light bridge in NOAA AR 11974 and its dynamic activity phenomena. As a result, we find that the light bridge has a weak, horizontal magnetic field, which is transported from the interior by large-scale convective upflow and is surrounded by strong, vertical fields of adjacent pores. In the chromosphere above the bridge, a transient brightening ...

  20. Bottom paving as a part of the low pressure culvert erected by the float-on method

    Directory of Open Access Journals (Sweden)

    T.V. Ivanova

    2012-12-01

    Full Text Available The widely used low pressure culverts are operated in the drop range between 1.5 and 5.0 meters. They distinguish by the near critical pairing mode of bays: in the downstream the true hydraulic jump does not develop. In this case the undular hydraulic jump develops in the downstream. Article is devoted to the issues of the improvement of bottom paving structures in low pressure constructions and the technology of its erecting. Features of controlling the near-critical flows arising during the operation are analyzed. Possible ways of technology improvement of structures are given illustrated by the example of bottom paving structures with guide elements. Results of hydraulic researches validating this construction are given.

  1. Prevention measures of honeycomb and pockmark on concrete surface of bridge and culvert%浅谈桥涵混凝土表面蜂窝麻面的防治措施

    Institute of Scientific and Technical Information of China (English)

    李俊

    2007-01-01

    结合福山立交至福山镇公路改建工程混凝土桥涵的施工过程,从多方面分析桥涵混凝土表面产生蜂窝麻面的原因,并提出防治措施,从而避免蜂窝麻面的产生,提高桥涵的外观质量.

  2. Performance assessment of resistance bridges and multimeters used at CMS

    International Nuclear Information System (INIS)

    Automatic balancing ac resistance bridges, ASL F18 and F700, and HP 3458A millimetres are the measurement instruments used by Center for Measurement Standards (CMS) for the calibration of standard platinum resistance thermometers (SPRTs), industrial platinum resistance thermometers (IPRTs), and liquid-in-glass thermometers (LIG) respectively. The inherent non-linearity of these measurement instruments could be a significant source of uncertainty and the absolute accuracy is especially critical to the primary instrument. A resistance bridge calibrator RBC 100, manufactured by 2K electronics, is a resistor network for the purpose of assessing their linearity and absolute accuracies of the foregoing thermometry bridges and meters. Each thirty-five normal measurements gives the linearity with 4.781 x 10-8, 4.982 x 10-7, and 6.371 x 10-5 Ω for F18, F700, and HP 3458A, however this deteriorates to 2.661 x 10-7 and 3.227 x 10-6 for two bridges while considering both normal and complementary data. Additionally, the possible contributions from the F18 bridge to the uncertainty of SPRT measurement at ITS-90 fixed points were investigated also

  3. Freestanding 3D supramolecular particle bridges: fabrication and mechanical behavior.

    Science.gov (United States)

    Ling, Xing Yi; Phang, In Yee; Schönherr, Holger; Reinhoudt, David N; Vancso, G Julius; Huskens, Jurriaan

    2009-06-01

    Freestanding particle bridges with controlled composition and macroscopic robustness are demonstrated by the use of supramolecular nanoparticle assembly. Self-assembly of nanoparticles, templating, and supramolecular glue infiltration are combined to form stable and ordered three-dimensional polystyrene particle composites on a polydimethylsiloxane stamp. Freestanding hybrid polystyrene nanoparticle bridges are obtained by transfer printing of the hybrid structures onto topographically patterned substrates via host-guest interactions. The mechanical robustness and rigidity of the particle bridges can be controlled by manipulating the layer-by-layer cycles of supramolecular glues of gold nanoparticles and dendrimers. Atomic force microscopy-based microbending results, in particular the location and force-dependent deflection behavior, confirm that the particle bridge fulfills the classical supported-beam characteristics. As estimated from classical beam theory, the bending moduli of the particle bridges vary between 0.8 and 1.1 GPa, depending on the degree of filling by the supramolecular glues. Failure analysis on the particle structure indicates linear elastic behavior and a plastic deformation upon failure. PMID:19373830

  4. Risk based bridge data collection and asset management and the role of structural health monitoring

    Science.gov (United States)

    Omenzetter, Piotr; Bush, Simon; Henning, Theunis; McCarten, Peter

    2011-04-01

    Bridges are critical to the operation and functionality of the whole road networks. It is therefore essential that specific data is collected regarding bridge asset condition and performance, as this allows proactive management of the assets and associated risks and more accurate short and long term financial planning. This paper proposes and discusses a strategy for collection of data on bridge condition and performance. Recognizing that risk management is the primary driver of asset management, the proposed strategy prioritizes bridges for levels of data collection including core, intermediate and advanced. Individual bridges are seen as parts of wider networks and bridge risk and criticality assessment emphasizes bridge failure or underperformance risk in the network context. The paper demonstrates how more reliable and detailed data can assist in managing network and bridge risks and provides a rationale for application of higher data collection levels for bridges characterized by higher risk and criticality. As the bridge risk and/or criticality increases planned and proactive integration of structural health monitoring (SHM) data into asset management is outlined. An example of bridge prioritization for data collection using several bridges taken from a national highway network is provided using an existing risk and criticality scoring methodology. The paper concludes with a discussion on the role of SHM in data collection for bridge asset management and where SHM can make the largest impacts.

  5. 75 FR 49408 - Navigation and Navigable Waters; Technical, Organizational, and Conforming Amendments, Bridges

    Science.gov (United States)

    2010-08-13

    ... Waters; Technical, Organizational, and Conforming Amendments, Bridges AGENCY: Coast Guard, DHS. ACTION... this rule is to make conforming amendments and technical corrections to Coast Guard bridge and... corrections and editorial, organizational, and conforming amendments and these changes will have...

  6. Wind Resistant Design of Bridges in Japan Developments and Practices

    CERN Document Server

    Fujino, Yozo; Tanaka, Hiroshi

    2012-01-01

    For long-span bridges, wind action is a dominant factor in their safety and serviceability. A large number of long-span bridges have been built in Japan over the past 30 years, and tremendous amounts of research and technical development have been accomplished in wind resistant design. This book is a compilation of the results of active research and development. Wind resistant design standards generated in Japan are described in the first few chapters. Then comes information such as design wind speed, structural damping, wind tunnel tests, and analyses, which provide the basis of the design standards. Wind-induced vibrations and their control of girders, towers, cables, and other features are explained with examples of field measurements. Comprehensive listings of Japanese experience in vibration control are also presented. Because achieving particularly dynamic safety against wind is still not an easy task, these data and information will be valuable assets for the wind-engineering and bridge-engineering com...

  7. Comparisons of bridges flutter derivatives and generalized ones

    Institute of Scientific and Technical Information of China (English)

    Fuyou XU; Airong CHEN; Zhe ZHANG; Cailiang HUANG

    2009-01-01

    The causes of the nonlinearity of self-excited aerodynamic force of bridge are interpreted from such two aspects as amplitude and wind velocity. The concept of "generalized flutter derivative" is proposed, and its physical meaning is illustrated. The graphs of the general-ized flutter derivatives of plate and Sutong Bridge section model are plotted. The characteristics of all generalized flutter derivatives are compared and analyzed, and their superiorities are verified. The results indicate that the physical meaning of generalized flutter derivatives are more explicit compared to the traditional ones. It is more convenient to understand the nonlinearity properties of self-excited aerodynamic force of bridge according to the generalized flutter derivatives graphs with the wind velocity as the horizontal coordinate.

  8. Proton production, neutralisation and reduction in a floating water bridge

    Science.gov (United States)

    Sammer, Martina; Wexler, Adam D.; Kuntke, Philipp; Wiltsche, Helmar; Stanulewicz, Natalia; Lankmayr, Ernst; Woisetschläger, Jakob; Fuchs, Elmar C.

    2015-10-01

    This work reports on proton production, transport, reduction and neutralization in floating aqueous bridges under the application of a high dc voltage (‘floating water bridge’). Recently possible mechanisms for proton transfer through the bridge were suggested. In this work we visualize and describe the production of protons in the anolyte and their neutralization in the catholyte. Apart from that, protons are reduced to hydrogen due to electrolysis. Microbubbles are detached instantly, due to the electrohydrodynamic flow at the electrode surface. No larger, visible bubbles are formed and the system degasses through the bridge due to its higher local temperature. A detailed analysis of trace elements originating from beaker material, anode or the atmosphere is presented, showing that their influence on the overall conduction compared to the contribution of protons is negligible. Finally, an electrochemical rationale of high voltage electrolysis of low ionic strength solutions is presented.

  9. Bridging UX and web development better results through team integration

    CERN Document Server

    Moffett, Jack

    2014-01-01

    The divide between UX and Web development can be stifling. Bridging UX and Web Development prepares you to break down those walls by teaching you how to integrate with your team's developers. You examine the process from their perspective, discovering tools and coding principles that will help you bridge the gap between design and implementation. With these tried and true approaches, you'll be able to capitalize on a more productive work environment. Whether you're a novice UX professional finding your place in the software industry and looking to nail down your technical skills, or a seasone

  10. Comparative Study of Layout Schemes for Suohe River Culvert Aqueduct%索河涵洞式渡槽槽身方案比选

    Institute of Scientific and Technical Information of China (English)

    王美斋; 杨顺群; 宋海印; 刘许超

    2011-01-01

    针对南水北调中线工程交叉渠系建筑物索河渡槽,充分考虑渡槽跨度大、流量大、结构复杂等特点,对比各种形式后提出矩形截面渡槽作为研究重点,并针对矩形截面,对比了双槽分缝外槽壁不加肋与双槽不分缝单隔墙两种槽身布置方案,采用大型通用计算程序ANSYS平台,开展两种方案槽身结构的三维空间有限元计算分析研究,结果表明双槽不分缝单隔墙方案具有工程量省、整体性好、整体应力变形水平较双槽分缝外槽壁不加肋方案小、拉应力满足设计要求的优点,但也具有底板端部不均匀沉降大的缺点.综合各结果,双槽不分缝单隔墙可作为南水北调中线工程索河渡槽的设计方案.%The aqueduct with rectangular cross-section was put forward as the research emphasis after comparing various forms and considering some characteristics such as the large aqueduct span, large flow and complicated structure according to SuoHe culvert aqueduct of South-to-north Water Diversion Project The scheme of dual culverts with joint without ribs and the one of dual culverts with a single wall without joint were contrasted,and the latter was chosen according to three-dimensional finite element analyses by ANSYS procedure. This scheme could save quantity and its integral performance is excellent And its integral stress and deformation level is better than the other scheme and its tensile stress meets the design requirements,but the uneven sedimentation is lager at the end of the baseplate. All in all, the scheme of dual culverts with a single wall without joint was chosen as the design scheme.

  11. Lasers as a Bridge between Atomic and Nuclear Physics

    OpenAIRE

    Matinyan, Sergei G.

    1997-01-01

    This paper reviews the application of optical and UV laser radiation to several topics in low-energy nuclear physics. We consider the laser-induced nuclear anti-Stokes transitions, the laser-assisted and the laser-induced internal conversion, and the Electron Bridge and Inverse Electron Bridge mechanisms as tools for deexciting and exciting of low-lying nuclear isomeric states. A study of the anomalous, by low-lying, nuclear isomeric states (on an example of the $^{229}$Th nucleus) is present...

  12. Bridging the gap between prep classes and freshman year

    OpenAIRE

    Simpson, Adam John

    2014-01-01

    One of the great strengths of the upper intermediate program at Sabancı University School of Languages is the extent to which it acts as a bridge between the preparatory English year and the kinds of lectures the students will be attending and the language they’ll be encountering when they progress to their freshman studies. A major part of this bridge is the series of lectures in mathematics and natural sciences (EMS) which the students attend for one hour a week and which form a percentage ...

  13. RECONSTRUCTION AND REINFORCEMENT OF BRIDGE ACROSS THE RIVER. SYLVA IN KUNGUR, RUSSIA

    Directory of Open Access Journals (Sweden)

    R. Ye. Heizn

    2010-04-01

    Full Text Available Sylva Bridge at Kungur city is one of the oldest road bridges in Perm region, the West Urals, Russia. Its erection was begun in 1912 and was interrupted with the First World War and the further events in Russia. The bridge was opened only in 1931. For 75 years of bridge operation the most part of bridge constructions has been acquired plural damages, both mechanical and corrosion. After the bridge inspection in 2003 and according to the calculations of its capacity, the decision on reconstruction of the bridge was accepted. The purpose of rehabilitation was to replace the timber deck by steel orthotropic deck with asphalt pavement. A new deck was to be engaged in combined action with the existing metal structures with the help of socles with high-strength bolts. Due to this, the bridge carrying capacity was increased as required by the present standards. In 2006, after tests, the bridge was opened for traffic.

  14. Thermal Bridges in Building Construction - Measurements and Calculations

    DEFF Research Database (Denmark)

    Rose, Jørgen

    The thesis investigates detailed calculation methods for evaluating heat loss through building envelope constructions, or more specific, thermal bridges. First a detailed description of the calculation methods, i.e. both calculation programs and guidelines, for calculating typical thermal bridges...... in building envelope constructions is given. After this a validation of both programs and guidelines is presented. The validation is performed by comparing calculated U-values with Guarded Hot Box measurements. The last part of the thesis discusses the possibilities of utilising the results of detailed...

  15. New Concepts in Fish Ladder Design: Analysis of Barriers to Upstream Fish Migration, Volume IV of IV, Investigation of the Physical and Biological Conditions Affecting Fish Passage Success at Culverts and Waterfalls, 1982-1984 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Powers, Patrick D.; Orsborn, John F.

    1985-08-01

    A synopsis of the project components was prepared to provide an overview for persons who are not fisheries scientists or engineers. This short report can be used also by technical persons who are interested in the scope of the project, and as a summary of the three main reports. The contents includes an historical perspective on fishway design which provides the basis for this project. The major project accomplishments and significant additions to the body of knowledge about the analysis and design of fishways are discussed. In the next section the research project organization, objectives and components are presented to familiarize the reader with the scope of this project. The summary report concludes with recommendations for assisting in the enhancement and restoration of fisheries resources from the perspective of fish passage problems and their solution. Promising research topics are included.

  16. Theory Development: A Bridge between Practice and Research

    Science.gov (United States)

    Southern, Stephen; Devlin, James

    2010-01-01

    Theory development is an intentional process by which marriage and family counselors may bridge the gap between research and practice. The theory building process includes inductive and deductive forms of reasoning, qualitative and quantitative approaches to knowledge development, and diffusion of innovations. Grounded theory provides an…

  17. Bridging Science and Practice to Improve Patient Care

    Science.gov (United States)

    Kazdin, Alan E.

    2009-01-01

    Replies to the comments by Tyron, Silverstein and Auerbach, and Raps on the author's original article. I was very pleased to read these comments about the priority of bridging research and clinical practice and to have the benefit of further perspectives on how this goal might be achieved. The article to which these comments were addressed…

  18. International Higher Education's Scholar-Practitioners: Bridging Research and Practice

    Science.gov (United States)

    Streitwieser, Bernhard, Ed.; Ogden, Anthony, Ed.

    2016-01-01

    The idea of the professional who bridges both research and practice has been largely overlooked and at times even disregarded by the academic and administrative structures that govern activity in higher education today. In international higher education, the number of students who now engage in mobility and exchange has expanded globally, along…

  19. Building Bridges between Neuroscience, Cognition and Education with Predictive Modeling

    Science.gov (United States)

    Stringer, Steve; Tommerdahl, Jodi

    2015-01-01

    As the field of Mind, Brain, and Education seeks new ways to credibly bridge the gap between neuroscience, the cognitive sciences, and education, various connections are being developed and tested. This article presents a framework and offers examples of one approach, predictive modeling within a virtual educational system that can include…

  20. Thermal bridges. Causes and impacts, information on reduction and avoidance; Waermebruecken. Ursachen und Auswirkungen, Hinweise zur Verringerung und Vermeidung

    Energy Technology Data Exchange (ETDEWEB)

    Feist, Wolfgang; Born, Rolf

    2012-11-15

    Thermal bridges increase the heat demand, affect the thermal comfort, facilitate mould cultures and cause structural damage. Many thermal bridges can be avoided by proper building construction details. At least the impact of thermal bridges can be avoided.

  1. Information Geography: A Bridge between Engineering and the Social Sciences

    Science.gov (United States)

    Paradiso, Maria

    2006-01-01

    This paper presents the metaphor of engineering and the social sciences located on either side of a chasm and connected by the bridge of information geography. Information geography is not an integral part of engineering and is a new field within geography, a social science discipline. The specialty of information geography is one of the newest in…

  2. [Extension bridges. A bibliographic evaluation and the clinical indications].

    Science.gov (United States)

    Irato, A; Garrone, P; Catapano, S; Carossa, S

    1990-11-01

    Extension bridges are a valid alternative to partial and implanted prostheses for the rehabilitation of small intercalary or distal lacunae. Following a critical review of published reports on the subject and the assessment of longitudinal studies, the authors examine the clinical parameters and technical procedures used to implement these prosthetic reconstructions. PMID:2084528

  3. Building More Solid Bridges between Buddhism and Western Psychology

    Science.gov (United States)

    Sugamura, Genji; Haruki, Yutaka; Koshikawa, Fusako

    2007-01-01

    Introducing the ways of cultivating mental balance, B. A. Wallace and S. L. Shapiro attempted to build bridges between Buddhism and psychology. Their systematic categorization of Buddhist teachings and extensive review of empirical support from Western psychology are valuable for future study. However, it remains a matter of concern that some more…

  4. Designing for Anxiety Therapy, Bridging Clinical and Non-Clinical

    DEFF Research Database (Denmark)

    Bertelsen, Olav Wedege; Kramp, Gunnar

    2012-01-01

    In this position paper we discuss, in terms of the concept of boundary objects, how a mobile application, the MIKAT.app, bridge between clinical intervention in anxiety therapy, and life and coping strategies outside the clinic and across phases of being a person suffering from, or having suffered...... from anxiety. Thereby, we hope to provide a counterpoint in the discussion on illness trajectories....

  5. Service Life and Maintenance Modelling of Reinforced Concrete Bridge Decks

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    Recent research in the area of assessment and maintenance of reinforced concrete bridge decks is presented in this paper. Three definitions of service lifetime are introduced and the difficult problem of assessing the service life is discussed. A stochastic modelling of corrosion and corrosion...

  6. Herzog:A Bridge between Modernism and Postmodernism

    Institute of Scientific and Technical Information of China (English)

    冯丽霞; 王宏; 史晓燕

    2013-01-01

    Herzog is one of Saul Bellow’s most successful novels, which laid a solid foundation for his winning the Oscar Award of Literature. This paper is intended to prove Herzog is a bridge between Modernism and Postmodernism by comparative study on the thematic and formal transformation of the whole novel based on textual analysis and Gerald Genette’s narratology theories.

  7. Bridging the gap between instructional design and double loop learning

    NARCIS (Netherlands)

    Spoelstra, Howard; Matera, Maristella; Rusman, Ellen; Van Bruggen, Jan; Koper, Rob

    2006-01-01

    Spoelstra, H., Matera, M., Rusman, E., Van Bruggen, J., & Koper, R. (2006). Bridging the gap between instructional design and double loop learning. Proceedings of IV International Conference on Multimedia and Information and Communication Technologies in Education (m-ICTE2006). November, 22-25, 2006

  8. Matters of Taste: Bridging Molecular Physiology and the Humanities

    Science.gov (United States)

    Rangachari, P. K.; Rangachari, Usha

    2015-01-01

    Taste perception was the focus of an undergraduate course in the health sciences that bridged the sciences and humanities. A problem-based learning approach was used to study the biological issues, whereas the cultural transmutations of these molecular mechanisms were explored using a variety of resources (novels, cookbooks, and films). Multiple…

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

    Science.gov (United States)

    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…

  10. Bridging Developmental Systems Theory and Evolutionary Psychology Using Dynamic Optimization

    Science.gov (United States)

    Frankenhuis, Willem E.; Panchanathan, Karthik; Clark Barrett, H.

    2013-01-01

    Interactions between evolutionary psychologists and developmental systems theorists have been largely antagonistic. This is unfortunate because potential synergies between the two approaches remain unexplored. This article presents a method that may help to bridge the divide, and that has proven fruitful in biology: dynamic optimization. Dynamic…

  11. Academic Wholism: Bridging the Gap between High School and College

    Science.gov (United States)

    Giuliano, Barbara; Sullivan, Judith

    2007-01-01

    Without adequate reading comprehension, writing proficiency, math competency, and critical thinking skills, students pursuing higher education are vulnerable to failure. An environmental Science course built around academic wholism is the focus of a summer program designed to bridge the gap between high school and college. Students self-reflect…

  12. Online Book Clubs: Bridges between Old and New Literacies Practices

    Science.gov (United States)

    Scharber, Cassandra

    2009-01-01

    In this Digital Literacies column, online book clubs are offered as one example of how to effectively bridge old and new literacy practices. These Internet-based book clubs capitalize on children's interest in new literacy practices while complementing, and hopefully encouraging, traditional reading practices. Examples from online book clubs…

  13. Collective Genius: Bridging the Gaps among Research, Innovation and Practice

    Science.gov (United States)

    O'Hair, Mary John

    2011-01-01

    In this article, the author focuses on bridging the gaps among research, innovation, and practice. First, the author reflects on historical perspectives involving the use of research to improve education and serve the public good. Second, the author explores the current climate as reflected by three national reports highlighting future roles of…

  14. Bridging Implementation, Knowledge, and Ambition Gaps to Eliminate Tuberculosis

    Centers for Disease Control (CDC) Podcasts

    2011-02-22

    In this podcast, Dr. Kenneth Castro, director of CDC's Division of Tuberculosis Eliminatio,discusses bridging implementation, knowledge, and ambition gaps to eliminate tuberculosis.  Created: 2/22/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 3/2/2011.

  15. A novel bridge scour monitoring and prediction system

    Science.gov (United States)

    Valyrakis, Manousos; Michalis, Panagiotis; Zhang, Hanqing

    2015-04-01

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

  16. Programmevaluierung Bridge

    OpenAIRE

    Warta, Katharina; Good, Barbara; Geyer, Anton

    2009-01-01

    BRIDGE is an initiative funded by the Ministry for Transport, Innovation and Technology (BMVIT) that aims to close the “funding gap” between basic and applied research in stand-alone projects with the primary objective of jointly developing the potential of basic and applied research. BRIDGE acts as an  umbrella structure under which the Austrian Science Fund (FWF) and the  Austrian Research Promotion Agency (FFG) coordinate two thematically open funding programmes: The ...

  17. MYOCARDIAL BRIDGING - CLINICAL AND ANGIOGRAPHIC PROFILE IN LAST 5 YEARS; A STUDY OF 129 CASES

    Directory of Open Access Journals (Sweden)

    Abhilash S P

    2010-11-01

    Full Text Available Aims of study : To assess the clinical and angiographical profile of myocardial bridging from consecutive coronary angiograms done over last 5 years at Medical college, Thiruvananthapuram. To assess the risk of cardiovascular events and the risk of accelerated atherosclerosis in isolated myocardial bridging. Methods : Consecutive coronary angiograms done at Medical college Thiruvananthapuram from 04/02/2005 to 31/03/2010 were reviewed for myocardial bridging. A total of 10492 coronary angiograms were reviewed. Myocardial bridges with systolic lumen reduction of more than 50% were considered for analysis. Quantitative coronary angiography (QCA was used for analysis. Clinical presentation as well as correlation with structural heart disease and coronary heart disease was assessed. Results: Incidence of myocardial bridges was 1.23%. Of the 129 patients with myocardial bridges 63 ( 48.8% had associated significant coronary artery disease. Remaining 66 (51.2% patients presented with isolated bridges. Out of these 66 patients with isolated myocardial bridges, 7 (10.6% patients presented with acute myocardial infarction and 3 (4.5% presented with cardiac arrhythmias. Of the 63 patients with significant coronary disease 11 (17.5% patients had single vessel disease and they had the culprit lesion and myocardial bridge seen in the same vessel. Most common location of myocardial bridge was mid LAD (64.9% followed by distal LAD (23.8%. Length of bridge was 20 mm in 35.7%. Mean percentage of systolic obliteration by the bridge was 74.5%. 100% systolic obliteration was seen in 7.79% of isolated bridges and in 9.79% of bridges with CAD. Among 120 rhuematic heart disease patients who underwent coronary angiogram, 10 (8.3% patients had myocardial bridging. 12.1% of all HCM patients who underwent coronary angiograms had myocardial bridging. Conclusion: Myocardial bridging can be lethal- can accelerate atherosclerosis, can precipitate acute MIs and life

  18. Probabilistic seismic response and reliability assessment of isolated bridges

    Institute of Scientific and Technical Information of China (English)

    Giuseppe Carlo Marano

    2005-01-01

    Bridge seismic isolation strategy is based on the reduction of shear forces transmitted from the superstructure to the piers by two means: shifting natural period and earthquake input energy reduction by dissipation concentrated in protection devices. In this paper, a stochastic analysis of a simple isolated bridge model for different bridge and device parameters is conducted to assess the efficiency of this seismic protection strategy. To achieve this aim, a simple nonlinear softening constitutive law is adopted to model a wide range of isolation devices, characterized by only three essential mechanical parameters. As a consequence of the random nature of seismic motion, a probabilistic analysis is carried out and the time modulated Kanai-Tajimi stochastic process is adopted to represent the seismic action. The response covariance in the state space is obtained by solving the Lyapunov equation for a stochastic linearized system. After a sensitivity analysis, the failure probability referred to extreme displacement and the mean value of dissipated energy are assessed by using the introduced stochastic indices of seismic bridge protection efficiency. A parametric analysis for protective devices with different mechanical parameters is developed for a proper selection of parameters of isolation devices under different situations.

  19. Law, Ethics, and Social Justice: Commentary from the Bridge

    Science.gov (United States)

    Stefkovich, Jacqueline A.

    2012-01-01

    Providing commentary on this "Journal of School Leadership's" special issue, "Constructing a Bridge Between Law and Social Justice: An Ethical Journey," has been not only a daunting task because of the complex nature of this topic but also a humbling experience because of the superior quality of these articles. At the same time, it is most…

  20. Bridging the Gap between Research and Practice: Voice of Mediators

    Science.gov (United States)

    Mehrani, Mehdi B.

    2014-01-01

    The present study aimed to explore the strategies that could be potentially employed in the Iranian ELT context to bridge the gap between research and practice. Data were collected through conducting a "focus group discussion" with a number of practitioner-researchers. The findings showed that to improve the relationship between…

  1. Practice of One Health approaches: Bridges and barriers in Tanzania

    Directory of Open Access Journals (Sweden)

    Kim A. Kayunze

    2014-04-01

    Full Text Available The practice of one health approaches in human and animal health programmes is influenced by type and scope of bridges and barriers for partnerships. It was thus essential to evaluate the nature and scope of collaborative arrangements among human, animal, and wildlife health experts in dealing with health challenges which demand inter-sectoral partnership. The nature of collaborative arrangement was assessed, and the respective bridges and barriers over a period of 12 months (July 20011 to June 2012 were identified. The specific objectives were to: (1 determine the proportion of health experts who had collaborated with other experts of disciplines different from theirs, (2 rank the general bridges for and barriers against collaboration according to the views of the health experts, and (3 find the actual bridges for and barriers against collaboration among the health experts interviewed. It was found that 27.0% of animal health officers interviewed had collaborated with medical officers while 12.4% of the medical officers interviewed had collaborated with animal health experts. Only 6.7% of the wildlife officers had collaborated with animal health experts. The main bridges for collaboration were instruction by upper level leaders, zoonotic diseases of serious impacts, and availability of funding. The main barriers for collaboration were lack of knowledge about animal/human health issues, lack of networks for collaboration, and lack of plans to collaborate. This thus calls for the need to curb barriers in order to enhance inter-sectoral collaboration for more effective management of risks attributable to infectious diseases of humans and animals.

  2. Rapid-to-deploy wireless monitoring systems for static and dynamic load testing of bridges: validation on the Grove Street Bridge

    Science.gov (United States)

    Hou, Tsung-Chin; Lynch, Jerome P.

    2006-03-01

    Bridge management officials have expressed a keen interest in the use of low-cost and easy-to-install wireless sensors to record bridge responses during short-term load testing. To illustrate the suitability of wireless sensors for short-term monitoring of highway bridges, a wireless monitoring system is installed upon the Grove Street Bridge to monitor structural responses during static and dynamic load testing. Specifically, load testing of the Grove Street Bridge is conducted after its construction to validate the behavior of a novel jointless bridge deck constructed from a high-performance fiber reinforced cementitious composite (HPFRCC) material. A heterogeneous array of sensing transducers are installed in the bridge including metal foil strain gages, accelerometers and linear variable differential transducers (LVDTs). First, the acceleration response of the bridge is monitored by the wireless system during routine traffic loading. Modal parameters (modal frequencies and mode shapes) are calculated by the wireless sensors so that an analytical model of the bridge constructed in a standard commercial finite element package can be updated off-line. Next, the bridge is closed to traffic and trucks of known weight are parked on the bridge to induce static deformations. The installation strategy of the wireless monitoring system during static load testing is optimized to monitor the strain and rotation response of the HPFRCC deck. The measured static response of the deck is compared to that predicted by the updated analytical model.

  3. Management Education: Classifying Business Curricula and Conceptualizing Transfers and Bridges

    OpenAIRE

    Davar Rezania; Mike Henry

    2010-01-01

    Traditionally, higher academic education has favoured acquisition of individualized conceptual knowledge over context-independent procedural knowledge. Applied degrees, on the other hand, favour procedural knowledge. We present a conceptual model for classifying a business curriculum. This classification can inform discussion around difficulties associated with issues such as assessment of prior learning, as well as transfers and bridges from applied degrees to baccalaureate degrees in busine...

  4. Coupled SPH-FE analysis for dynamic response of box culvert subjected to subsurface blast%土中爆炸作用下箱涵动力响应的SPH-FE耦合分析

    Institute of Scientific and Technical Information of China (English)

    崔溦; 宋慧芳; 张社荣

    2012-01-01

    A fully coupled numerical analysis technology is used to simulate the response of a large-scale box culvert under blast load, in which SPH method is adopted to model the near field medium, while FEM is used to model the far field soil and reinforced concrete box culvert. The results show that the damage position and degree are closely related to charge relative position to box culvert. There is an obvious difference among stress and deformation of box culvert under different detonation. Especially at the center position of the wall, there is an obvious effect of soil flow on reload and change of stress under different detonation. The final conclusion show that the coupled SPH-FE analysis technology can satisfy calculation efficiency and engineering requirements.%采用SPH与FE耦合的数值分析技术,SPH法用于模拟爆破近域土体,FE法用于模拟远场土体和钢筋混凝土箱涵,研究了土中爆炸作用下钢筋混凝土箱涵的动力响应.研究结果表明:箱涵损伤区域及损伤程度与土中爆炸位置密切相关 ;不同爆炸位置下箱涵受力和变形规律存在较大差异,尤其是边墙中间位置,受土体变形流动影响,爆炸位置的不同会引起明显的二次加载和拉压变化.SPH与FE耦合分析技术可以满足土中爆炸对结构物影响问题的计算效率和工程分析要求.

  5. Preliminary design and parametric study of 1400 m partially earth-anchored cable-stayed bridge

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The preliminary design and parametric study of 1400 m partially earth-anchored cable-stayed bridge are described. Static per-formance of this new type of bridge is discussed. Compared with fully self-anchored cable-stayed bridge, its advantages in fin-ished state are summarized. Based on numerical calculation, effects of several structural parameters on static performance are presented.

  6. Microwave generation and complex microwave responsivity measurements on small Dayem bridges

    DEFF Research Database (Denmark)

    Pedersen, Niels Falsig; Sørensen, O; Mygind, Jesper;

    1977-01-01

    Measurements of the active properties of a Dayem micro-bridge at X-band frequencies is described. The bridge was mounted in a microwave cavity designed to match the bridge properly and the microwave output from the cavity was detected using a sensitive X-band spectrometer. Microwave power...

  7. Bridging the gap between science and decision making

    OpenAIRE

    von Winterfeldt, Detlof

    2013-01-01

    All decisions, whether they are personal, public, or business-related, are based on the decision maker’s beliefs and values. Science can and should help decision makers by shaping their beliefs. Unfortunately, science is not easily accessible to decision makers, and scientists often do not understand decision makers’ information needs. This article presents a framework for bridging the gap between science and decision making and illustrates it with two examples. The first example is a persona...

  8. Local, regional and national experiences on bridging: US perspectives

    OpenAIRE

    Putnam, Michelle

    2009-01-01

    Introduction Bridge building work in the US is primarily local and voluntary, involving professionals at individual agencies and organizations (public and private) who work towards specific goals. However, federal mandates intended to reduce nursing home admissions and increase access to home and community based services through new model collaboration programs are hastening this work. Description of policy practice Successful short-term ‘grassroots’ coalitions advocating for specific health ...

  9. Managing concrete bridges: Methods for reducing costs and user inconveniences

    DEFF Research Database (Denmark)

    Goltermann, Per

    2005-01-01

    . These approaches are focused on cost reductions, but must as well lead to a reduction of the user inconveniences (traffic delays, noise, dust) and to a reduction of the environmental impact. These approaches can be based on an assessment of the structures safety, which incorporates the inaccuracies......The paper presents experiences from modern bridge maintenance management, which has been forced to develop new and cost-efficient approaches in order to cope with the increase in overall deterioration of the aging bridge stock, the growing requirements to accessibility and the decreasing budgets...... in the condition assessments, the models and the predictions in the strategies and the cost estimations. This may lead to increased inspection frequencies, detailed simulations, monitoring and testing to be used as alternatives to extensive repairs, rehabilitations or strengthening. The approaches will in other...

  10. Performance of Bridge Decks and Girders with Lightweight Aggregate Concrete

    OpenAIRE

    Ramirez, J.A.; Olek, J.; Rolle, Eric Joseph; Manlone, Brian J.

    2000-01-01

    Structural lightweight concrete is a very versatile material and Haydite and Minergy lightweight aggregates can be utilized in the mixture development of concrete for use in girders and decks in bridges. More widespread use of lightweight aggregates (LWA) would result in savings in construction cost due to considerable dead load reduction. The materials phase of this research study evaluated the fresh concrete properties (slump, unit weight, and air content), the mechanical properties of ha...

  11. Building Bridges and Interfaces: Toward the Next Generation of UIMS

    OpenAIRE

    Hartson, H. Rex; Hix, Deborah

    1987-01-01

    User interface management systems (UIMS) have established themselves in both research and commercial arenas. We present several generations in UIMS evolution and discuss some problems of the early generations. In particular, we discuss the problems of a gap between methods used by behavioral scientists and computer scientists during the process of building interfaces. We present an empirical approach to begin bridging this gap and results of our preliminary observations: a human-computer int...

  12. Price, Availability, and Youth Obesity: Evidence From Bridging the Gap

    OpenAIRE

    Chaloupka, Frank J.; Powell, Lisa M.

    2009-01-01

    After a decade of analyzing environmental influences on substance use and its consequences among youth in the United States, the Robert Wood Johnson Foundation's Bridging the Gap program has begun studying the effect of environmental factors on youth physical activity, diet, and weight outcomes. Much of this research has focused on access to food, as reflected by availability and price. Program researchers have documented disparities in access to healthy foods and opportunities for physical a...

  13. Heavy Axion on Sark Bridge Between Higgs and Technicolor Models

    Science.gov (United States)

    Frampton, P. H.; Yanagida, T.

    It is shown how imposition of Peccei-Quinn symmetry leads to a heavy axion and strong constraints in the sark model. The axion and sark masses are derived. Analysis of chiral symmetry breaking leads to mass formulae for pseudo-Goldstone bosons; the lightest is between 44 and 125 GeV. A general picture which bridges between the sark model and a technicolor model, in terms of a new angle, is proposed.

  14. Stress and noises of steel box girders in Sutong Bridge

    Institute of Scientific and Technical Information of China (English)

    Xue Tao; Chen Zhijian; Dong Xuewu

    2008-01-01

    Sutong Bridge is a cable-stayed bridge with a main span of 1 088 m.370 high-precision stress monitoring measured data show that in the process of hoisting the steel box girders,the stress of the main girders is in the fluctuant and complex state and many meteorological factors,such as sunshine radiation,temperature and wind,have important influence on the change of stress of the steel box girders.According to the real-time weather data,the stress data after the process of wavelet denoising from representative measuring points in different weather conditions is picked to estab-lish the stress response brought by meteorological factors with Layered Separation method,thereby basically eliminating the influence of meteorological factors on the stress of main girders,so that accurate and reliable stress data can be got for steel box girders adjustment and cable-tensioned construction control.

  15. Neuroscience and education: prime time to build the bridge.

    Science.gov (United States)

    Sigman, Mariano; Peña, Marcela; Goldin, Andrea P; Ribeiro, Sidarta

    2014-04-01

    As neuroscience gains social traction and entices media attention, the notion that education has much to benefit from brain research becomes increasingly popular. However, it has been argued that the fundamental bridge toward education is cognitive psychology, not neuroscience. We discuss four specific cases in which neuroscience synergizes with other disciplines to serve education, ranging from very general physiological aspects of human learning such as nutrition, exercise and sleep, to brain architectures that shape the way we acquire language and reading, and neuroscience tools that increasingly allow the early detection of cognitive deficits, especially in preverbal infants. Neuroscience methods, tools and theoretical frameworks have broadened our understanding of the mind in a way that is highly relevant to educational practice. Although the bridge's cement is still fresh, we argue why it is prime time to march over it.

  16. Concrete bridge deck early problem detection and mitigation using robotics

    Science.gov (United States)

    Gucunski, Nenad; Yi, Jingang; Basily, Basily; Duong, Trung; Kim, Jinyoung; Balaguru, Perumalsamy; Parvardeh, Hooman; Maher, Ali; Najm, Husam

    2015-04-01

    More economical management of bridges can be achieved through early problem detection and mitigation. The paper describes development and implementation of two fully automated (robotic) systems for nondestructive evaluation (NDE) and minimally invasive rehabilitation of concrete bridge decks. The NDE system named RABIT was developed with the support from Federal Highway Administration (FHWA). It implements multiple NDE technologies, namely: electrical resistivity (ER), impact echo (IE), ground-penetrating radar (GPR), and ultrasonic surface waves (USW). In addition, the system utilizes advanced vision to substitute traditional visual inspection. The RABIT system collects data at significantly higher speeds than it is done using traditional NDE equipment. The associated platform for the enhanced interpretation of condition assessment in concrete bridge decks utilizes data integration, fusion, and deterioration and defect visualization. The interpretation and visualization platform specifically addresses data integration and fusion from the four NDE technologies. The data visualization platform facilitates an intuitive presentation of the main deterioration due to: corrosion, delamination, and concrete degradation, by integrating NDE survey results and high resolution deck surface imaging. The rehabilitation robotic system was developed with the support from National Institute of Standards and Technology-Technology Innovation Program (NIST-TIP). The system utilizes advanced robotics and novel materials to repair problems in concrete decks, primarily early stage delamination and internal cracking, using a minimally invasive approach. Since both systems use global positioning systems for navigation, some of the current efforts concentrate on their coordination for the most effective joint evaluation and rehabilitation.

  17. Life cycle and performance based seismic design of major bridges in China

    Institute of Scientific and Technical Information of China (English)

    FAN Lichu

    2007-01-01

    The idea of life cycle and performance based seismic design of major bridges is introduced.Based on the key components and non-key components of a bridge and the consideration of the inspectability,replaceability,reparability,controllability and retrofitability of the bridge components,different seismic design levels and expected performance objectives are suggested for the major bridges in China.The vulnerability analysis and progressive collapse analysis,as well as risk assessment,are also proposed to be the important issues to study in order to guide the seismic design of major bridges in the future.

  18. Tubular Bridges for Bronchial Epithelial Cell Migration and Communication

    OpenAIRE

    Zani, Brett G.; Laura Indolfi; Edelman, Elazer R.

    2010-01-01

    BACKGROUND: Biological processes from embryogenesis to tumorigenesis rely on the coordinated coalescence of cells and synchronized cell-to-cell communication. Intercellular signaling enables cell masses to communicate through endocrine pathways at a distance or by direct contact over shorter dimensions. Cellular bridges, the longest direct connections between cells, facilitate transfer of cellular signals and components over hundreds of microns in vitro and in vivo. METHODOLOGY/PRINCIPAL FIND...

  19. Cellular bridges: Routes for intercellular communication and cell migration

    OpenAIRE

    Zani, Brett G.; Edelman, Elazer R.

    2010-01-01

    Cell-to-cell communication is the basis of all biology in multicellular organisms, allowing evolution of complex forms and viability in dynamic environments. Though biochemical interactions occur over distances, physical continuity remains the most direct means of cellular interactions. Cellular bridging through thin cytoplasmic channels—plasmodesmata in plants and tunneling nanotubes in animals—creates direct routes for transfer of signals and components, even pathogens, between cells. Recen...

  20. Bridging the Gap Between Engineering Workforce Needs and Student Engagement

    OpenAIRE

    Goold, Eileen

    2015-01-01

    This paper is inspired by the development of the proposed new technological university in Dublin; TU4Dublin is to become “Dublin’s Globally Engaged University” and is to be located at the nexus between learning and engagement (TU4Dublin, 2015). This study investigates engineering education in the context of career focused education. The main objective of this study is to investigate whether engineering students’ cognitive engagement benefits from bridging the gap between technical issues and ...

  1. Train–Bridge Interaction : Literature Review and Parameter Screening

    OpenAIRE

    Arvidsson, Therese

    2014-01-01

    New railway lines are continuously being constructed and existing lines are upgraded. Hence, there is a need for research directed towards efficient design of the supporting structures. Increasingly advanced calculation methods can be motivated, especially in projects where huge savings can be obtained from verifying that existing structures can safely support increased axle loads and higher speeds. This thesis treats the dynamic response of bridges under freight and passenger train loads. Th...

  2. Multidisciplinarity, Interdisciplinarity, and Bridging Disciplines: A Matter of Process

    Directory of Open Access Journals (Sweden)

    Dawn Youngblood

    2007-01-01

    Full Text Available Bridging disciplines have much to teach regarding how to combine analytical tools to tackle problems and questions that cross traditional disciplinary boundaries. This article explores interdisciplinary aspects of two long established bridging disciplines--geography and anthropology--in order to consider what the relatively young undertaking labeled “interdisciplinary studies” can learn from their long existence. It considers the fallacy of nomothetic claim as well as the fruitful production of solutions by viewing process (methodology, not domain (academic turf, as the key to interdisciplinary success. Staking claim to interdisciplinarity is shown to be unproductive while finding the need for interdisciplinary approaches and following the mandates of that need strengthens both the disciplines and interdisciplinary studies.

  3. Point process bridges and weak convergence of insider trading models

    OpenAIRE

    Cetin, Umut; Xing, Hao

    2013-01-01

    We construct explicitly a bridge process whose distribution, in its own filtration, is the same as the difference of two independent Poisson processes with the same intensity and its time $1$ value satisfies a specific constraint. This construction allows us to show the existence of Glosten-Milgrom equilibrium and its associated optimal trading strategy for the insider. In the equilibrium the insider employs a mixed strategy to randomly submit two types of orders: one type trades in the same ...

  4. Nonlinear Dynamic Reliability of Coupled Stay Cables and Bridge Tower

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Nonlinear vibration can cause serious problems in long span cable-stayed bridges. When the internal resonance threshold is reached between the excitation frequency and natural frequency,large amplitudes occur in the cable. Based on the current situation of lacking corresponding constraint criteria, a model was presented for analyzing the dynamic reliability of coupling oscillation between the cable and tower in a cable-stayed bridge. First of all, in the case of cable sag, the d'Alembert principle is applied to studying the nonlinear dynamic behavior of the structure, and resonance failure interval of parametric oscillation is calculated accordingly. Then the dynamic reliability model is set up using the JC method. An application of this model has been developed for the preliminary design of one cable-stayed bridge located on Hai River in Tianjin, and time histories analysis as well as reliability indexes have been obtained. When frequency ratio between the cable and tower is approaching 1∶2, the reliability index is 0.98, indicating high failure probability. And this is consistent with theoretical derivation and experimental results in reference. This model, which is capable of computing the reliability index of resonance failure, provides theoretical basis for the establishment of corresponding rule.

  5. Capillary Breakup of a Liquid Bridge: Identifying Regimes and Transitions

    CERN Document Server

    Li, Yuan

    2016-01-01

    Computations of the breakup of a liquid bridge are used to establish the limits of applicability of similarity solutions derived for different breakup regimes. These regimes are based on particular viscous-inertial balances, that is different limits of the Ohnesorge number $Oh$. To accurately establish the transitions between regimes, the minimum bridge radius is resolved through four orders of magnitude using a purpose-built multiscale finite element method. This allows us to construct a quantitative phase diagram for the breakup phenomenon which includes the appearance of a recently discovered low-$Oh$ viscous regime. The method used to quantify the accuracy of the similarity solutions allows us to identify a number of previously unobserved features of the breakup, most notably an oscillatory convergence towards the viscous-inertial similarity solution. Finally, we discuss how the new findings open up a number of challenges for both theoretical and experimental analysis.

  6. Bridging the Gap between Design and Engineering in Packaging Development

    OpenAIRE

    Ten Klooster, R.; Lutters, D.

    2009-01-01

    Packaging designers often come up with splendid design proposals, without being aware of technical, marketing or economical restrictions. This leads to infeasible proposals, so many packaging design projects fail. To bridge the gap between design and marketing, a tool has been developed that shows several designs to an extensive community. Designers now have the possibility to get feedback of the target market on the design proposals. In a case study (redesigning a packaging), the...

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

    Science.gov (United States)

    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.

  8. Advanced assessment methods for elderly bridges. State-of-the-art and justification based on LCA

    OpenAIRE

    Soriano Chacón, Miriam

    2013-01-01

    [ANGLÈS] Many of the existing bridges do not satisfy the structural requirements specified in design codes for new bridges. However, many of these bridges must remain in service and therefore decisions must be made in order to maintain their safety. In the design of new bridges, it is accepted “to be on the safe side” inherent in the standards; but for an assessment of an elderly bridge this procedure should be removed in order to have a more realistic understanding of the stat...

  9. IceBridge Data Management and Access Strategies at NSIDC

    Science.gov (United States)

    Oldenburg, J.; Tanner, S.; Collins, J. A.; Lewis, S.; FitzGerrell, A.

    2013-12-01

    NASA's Operation IceBridge (OIB) mission, initiated in 2009, collects airborne remote sensing measurements over the polar regions to bridge the gap between NASA's Ice, Cloud and Land Elevation satellite (ICESat) mission and the upcoming ICESat-2 mission in 2016. OIB combines an evolving mix of instruments to gather data on topography, ice and snow thickness, high-resolution photography, and other properties that are more difficult or impossible to measure via satellite. Once collected, these data are stored and made available at the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado. To date, there are nearly 90 terabytes of data available, and there are about three more years of data collection left. The main challenges faced in data management at NSIDC are derived from the quantity and heterogeneity of the data. To deal with the quantity of data, the technical teams at NSIDC have significantly automated the data ingest, metadata generation, and other required data management steps. Heterogeneity of data and the evolution of the Operation over time make technical automation complex. To limit complexity, the IceBridge team has agreed to such practices as using specific data file formats, limiting file sizes, using specific filename templates, etc. These agreements evolve as Operation IceBridge moves forward. The metadata generated about the flights and the data collected thereon make the storage of the data more robust, and enable data discoverability. With so much metadata, users can search the vast collection with ease using specific parameters about the data they seek. An example of this in action is the IceBridge data portal developed at NSIDC, http://nsidc.org/icebridge/portal/. This portal uses the GPS data from the flights projected onto maps as well as other flight and instrument metadata to help the user find the exact data file they seek. This implementation is only possible with dependable data management beneath the surface. The data files

  10. Liquid bridge force between two unequal-sized spheres or a sphere and a plane

    Institute of Scientific and Technical Information of China (English)

    You chuan Chen; Yong zhi Zhao; Hong li Gao; Jin yang Zheng

    2011-01-01

    Liquid bridge force acting between wet particles is an important property in particle characterization.This paper deals with liquid bridge force between either two unequal-sized spherical particles or a sphere and a flat plate under conditions where gravitational effect arising from bridge distortion is negligible.In order to calculate the force of the liquid bridge efficiently and accurately,expressions of liquid configuration and liquid bridge force were derived by building a mechanical model,which assumes the liquid bridge to be circular in shape between either two unequal-sized spheres or a sphere and a plane.To assess the accuracy of the numerical results of the calculated liquid bridge forces,they were compared to the published experimental data.

  11. Vibration analysis of medium and small span bridges subjected to mixed marshalling freight trains

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    It has been reported several times that train derailment occurs when mixed marshalling freight trains traverse bridges at high speeds in China.This study aims to explain this phenomenon numerically based on the train-bridge coupling vibration theory and its associated computer program.The train-bridge vibration characteristic is analyzed by a computer program when mixed marshalling freight trains traverse 32-meter-span prestressed concrete simple beam bridges.The mechanism that dynamic responses of the bridges are prominent and that empty trains are inclined to derail are derived from the dynamic responses analysis.The analysis indicates that the significant differences of axle loads between heavy vehicles and empty vehicles produce periodic forced loadings of large amplitudes.These periodic loadings cause severe vibration of bridges.In turn,severe vibration of the bridges produces intensive counteraction to empty vehicles.

  12. Computer Simulation of Dynamic Interactions Between Vehicle and Long Span Box Girder Bridges

    Institute of Scientific and Technical Information of China (English)

    Lei Gong; Moe S.Cheung

    2008-01-01

    Moving vehicle loads,associated with roadway traffic can induce significant dynamic effects on the structural behaviours of bridges,especially for long-span bridges.The main objective of current research is to study traffic induced dynamic responses of long-span box-girder bridges.The finite element method has been employed in this study to obtain a three-dimensional mathematical model for the bridge system.For vehicle-bridge dynamic interaction analysis,the vehicle is modeled as a more realistic three-axle,six-wheel system,and the corresponding dynamic interaction equations have been derived.The bridge-vehicle inter- action is affected by many factors.The current study has been focused on such factors as:vehicle speed, vehicle damping ratio,multiple traffic lanes,mass ratio of vehicle and bridge,and dynamic characteristics of bridge.Case studies have been conducted to investigate these factors by using several box girder bridge examples including Confederation Bridge,the longest box girder bridge in the world.

  13. Building Bridges

    DEFF Research Database (Denmark)

    The report Building Bridges adresses the questions why, how and for whom academic audience research has public value, from the different points of view of the four working groups in the COST Action IS0906 Transforming Audiences, Transforming Societies – “New Media Genres, Media Literacy and Trust...... in the Media”, “Audience Interactivity and Participation”, “The Role of Media and ICT Use for Evolving Social Relationships” and “Audience Transformations and Social Integration”. Building Bridges is the result of an ongoing dialogue between the Action and non-academic stakeholders in the field of audience...

  14. Analysis and Comparison Based on Component Stress Factor of Dual Active Bridge and Isolated Full Bridge Boost Converters for Bidirectional Fuel Cells Systems

    DEFF Research Database (Denmark)

    Pittini, Riccardo; Mira Albert, Maria del Carmen; Zhang, Zhe;

    2014-01-01

    This paper presents an analysis and comparison of isolated topologies for bidirectional fuel cell systems. The analyzed topologies are the dua l active bridge (DAB) and the isolated full bridge boost converter (IFBBC). The analysis is performed based on the component stress factor (CSF). Results ...

  15. Science and the Humanities: Bridging the Gap.

    Science.gov (United States)

    Lepkowski, Wil

    1980-01-01

    Traces the recent history of humanities-based science since the publication of C. P. Snow's "Two Cultures and the Scientific Revolution." Discusses the establishment of science, technology, and society programs in universities. Presents viewpoints of leading scientists and humanists, including Ilya Prigogine, Carl Rubino, T. S. Kuhn, and Michel…

  16. Bridging EO Research, Operations and Collaborative Learning

    Science.gov (United States)

    Scarth, Peter

    2016-04-01

    Building flexible and responsive processing and delivery systems is key to getting EO information used by researchers, policy agents and the public. There are typically three distinct processes we tackle to get product uptake: undertake research, operationalise the validated research, and deliver information and garner feedback in an appropriate way. In many cases however, the gaps between these process elements are large and lead to poor outcomes. Good research may be "lost" and not adopted, there may be resistance to uptake by government or NGOs of significantly better operational products based on EO data, and lack of accessibility means that there is no use of interactive science outputs to improve cross disciplinary science or to start a dialog with citizens. So one of the the most important tasks, if we wish to have broad uptake of EO information and accelerate further research, is to link these processes together in a formal but flexible way. One of the ways to operationalize research output is by building a platform that can take research code and scale it across much larger areas. In remote sensing, this is typically a system that has access to current and historical corrected imagery with a processing pipeline built over the top. To reduce the demand on high level scientific programmers and allowing cross disciplinary researchers to hack and play and refine, this pipeline needs to be easy to use, collaborative and link to existing tools to encourage code experimentation and reuse. It is also critical to have efficient, tight integration with information delivery and extension components so that the science relevant to your user is available quickly and efficiently. The rapid expansion of open data licensing has helped this process, but building top-down web portals and tools without flexibility and regard for end user needs has limited the use of EO information in many areas. This research reports on the operalization of a scale independent time series

  17. Conceptual Coordination Bridges Information Processing and Neurophysiology

    Science.gov (United States)

    Clancey, William J.; Norrig, Peter (Technical Monitor)

    2000-01-01

    Information processing theories of memory and skills can be reformulated in terms of how categories are physically and temporally related, a process called conceptual coordination. Dreaming can then be understood as a story understanding process in which two mechanisms found in everyday comprehension are missing: conceiving sequences (chunking categories in time as a categorization) and coordinating across modalities (e.g., relating the sound of a word and the image of its meaning). On this basis, we can readily identify isomorphisms between dream phenomenology and neurophysiology, and explain the function of dreaming as facilitating future coordination of sequential, cross-modal categorization (i.e., REM sleep lowers activation thresholds, "unlearning").

  18. Medicine and management. Bridging the cultural gaps.

    Science.gov (United States)

    Kissick, W L

    1995-02-01

    Cost-effective health care requires the informed and intensive collaboration of medicine and management. Unfortunately, the two cultures tend to view the health care enterprise very differently. To physicians, the essence is individual physician-patient encounters, patient hospital days, nurse-patient contact hours, diagnoses, and procedures. To managers, the $1 trillion-plus colossus called health care is a challenge to corporate practices of finance, accounting, organization, planning, and personnel. The efforts of these two cultures to face medicine's dilemmas can result in conflict and confrontation--or in collaboration and synthesis. PMID:10140218

  19. Business and computing : Bridging the gap

    International Nuclear Information System (INIS)

    Information systems, in the form of paper files or electronic files on computer systems and digital storage devices are employed in the oil industry to handle data from 3 basic infrastructures: accounting, geotechnical, and administration. The accounting function was the main driving force behind the development of the computer. The geotechnical data storage and manipulation infrastructure has its basis in signal recording and processing related to seismic acquisition and well logging. The administrative infrastructure deals with documents and not just data. Management in the oil industry needs two main kinds of useful information: reports about their organization and about the marketplace. Using an example of an oil and gas enterprise whose aim is to pursue low cost shallow gas to increase production levels, the basic business process is shown to relate to land and prospect inventory management, tightly controlled drilling methods, gathering system and production facility standardization, logistics and planning models, and strong transportation and marketing management. The role of the computer in this process is to yield information, that is, to provide coordinated, integrated, useful information that facilitates the processes essential to accomplish the business's objectives

  20. Business and computing : Bridging the gap

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, B.; Coles, F.C. [Applied Terravision Systems Inc., Calgary, AB (Canada)

    1999-06-01

    Information systems, in the form of paper files or electronic files on computer systems and digital storage devices are employed in the oil industry to handle data from 3 basic infrastructures: accounting, geotechnical, and administration. The accounting function was the main driving force behind the development of the computer. The geotechnical data storage and manipulation infrastructure has its basis in signal recording and processing related to seismic acquisition and well logging. The administrative infrastructure deals with documents and not just data. Management in the oil industry needs two main kinds of useful information: reports about their organization and about the marketplace. Using an example of an oil and gas enterprise whose aim is to pursue low cost shallow gas to increase production levels, the basic business process is shown to relate to land and prospect inventory management, tightly controlled drilling methods, gathering system and production facility standardization, logistics and planning models, and strong transportation and marketing management. The role of the computer in this process is to yield information, that is, to provide coordinated, integrated, useful information that facilitates the processes essential to accomplish the business's objectives.

  1. Business and computing : Bridging the gap

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, B.; Coles, F.C. [Applied Terravision Systems Inc., Calgary, AB (Canada)

    1999-06-01

    Information systems, in the form of paper files or electronic files on computer systems and digital storage devices are employed in the oil industry to handle data from 3 basic infrastructures: accounting, geotechnical, and administration. The accounting function was the main driving force behind the development of the computer. The geotechnical data storage and manipulation infrastructure has its basis in signal recording and processing related to seismic acquisition and well logging. The administrative infrastructure deals with documents and not just data. Management in the oil industry needs two main kinds of useful information: reports about their organization and about the marketplace. Using an example of an oil and gas enterprise whose aim is to pursue low cost shallow gas to increase production levels, the basic business process is shown to relate to land and prospect inventory management, tightly controlled drilling methods, gathering system and production facility standardization, logistics and planning models, and strong transportation and marketing management. The role of the computer in this process is to yield information, that is, to provide coordinated, integrated, useful information that facilitates the processes essential to accomplish the business`s objectives.

  2. Building a bridge between AGU and SEG

    Science.gov (United States)

    Pellerin, Louise; Bradford, John H.

    2012-05-01

    AGU and the Society of Exploration Geophysicists (SEG) complement each other in many ways. SEG is known for strength in applied geophysics and method development, while AGU is known for application of geophysics to broader scientific questions in Earth and atmospheric sciences. These boundaries are of course gray, and there is substantial and complementary overlap of interests, particularly among some disciplines; these include the study of passive and active source seismology, gravity and magnetic anomalies, and electrical and electromagnetic methodologies, as well as interest in the application of these methods to crustal structure, near- surface geophysics, geothermal exploration, and basin analysis. Facilitating communication between members of SEG and those of AGU has a significant impact on the geophysical sciences. The AGU-SEG Collaboration Committee (ASCC) was established as part of the AGUSEG Alliance Agreement, signed in 2010. In the agreement, ASCC was "charged with considering and making recommendations to the respective organizations regarding other areas of cooperation, such as joint workshops or programs and continuing- education courses." The first committee-wide meeting was held on 11 February 2011. Subsequent meetings are scheduled every 4-6 weeks.

  3. Bridging the Gap between Academics and Industry

    OpenAIRE

    O'Kane, Colm

    2010-01-01

    The benefits of close collaboration with industry for undergraduate design students have been repeatedly emphasised in the literature. This paper describes the operation of a design competition as a collaborative project between the DIT School of Manufacturing and Design Engineering and an external company. Small groups of design students were set a design brief and guided through the year by company representatives and by their academic supervisors. Along with giving an example of problem-ba...

  4. Platelets: bridging hemostasis, inflammation, and immunity.

    Science.gov (United States)

    Jenne, C N; Urrutia, R; Kubes, P

    2013-06-01

    Although the function of platelets in the maintenance of hemostasis has been studied in great detail, more recent evidence has highlighted a central role for platelets in the host inflammatory and immune responses. Platelets by virtue of their large numbers and their ability to rapidly release a broad spectrum of immunomodulatory cytokines, chemokines, and other mediators act as circulating sentinels. Upon detection of a pathogen, platelets quickly activate and begin to drive the ensuing inflammatory response. Platelets have the ability to directly modulate the activity of neutrophils (phagocytosis, oxidative burst), endothelium (adhesion molecule and chemokine expression), and lymphocytes. Due to their diverse array of adhesion molecules and preformed chemokines, platelets are able to adhere to leukocytes and facilitate their recruitment to sites of tissue damage or infection. Furthermore, platelets directly participate in the capture and sequestration of pathogens within the vasculature. Platelet-neutrophil interactions are known to induce the release of neutrophil extracellular traps (NETs) in response to either bacterial or viral infection, and platelets have been shown to internalize pathogens, sequestering them in engulfment vacuoles. Finally, emerging data indicate that platelets also participate in the host immune response by directly killing infected cells. This review will highlight the central role platelets play in the initiation and modulation of the host inflammatory and immune responses.

  5. Biorefinery, the bridge between agriculture and chemistry

    NARCIS (Netherlands)

    Sanders, J.P.M.; Scott, E.L.; Mooibroek, H.

    2005-01-01

    The depletion in fossil feedstocks, increasing oil prices and the ecological problems associated with CO2 emissions are forcing the development of alternative resources for energy (heat and electricity), transport fuels and chemicals: the replacement of fossil resources with CO2 neutral biomass. Whe

  6. Robotics: A Bridge for Education and Technology.

    Science.gov (United States)

    Warnat, Winifred I.

    Robotics (robot usage) is discussed from a historical perspective with regard to its role in employment and education. Part 1 examines the transition from an industrial to an information society and speculates what the future might hold, particularly in terms of employment. Part 2 gives a historical overview of the robotics industry and discusses…

  7. Fundamental Concepts Bridging Education and the Brain

    Science.gov (United States)

    Masson, Steve; Foisy, Lorie-Marlène Brault

    2014-01-01

    Although a number of papers have already discussed the relevance of brain research for education, the fundamental concepts and discoveries connecting education and the brain have not been systematically reviewed yet. In this paper, four of these concepts are presented and evidence concerning each one is reviewed. First, the concept of…

  8. Giovanni: The Bridge between Data and Science

    Science.gov (United States)

    Shen, Suhung; Lynnes, Christopher; Kempler, Steven J.

    2012-01-01

    NASA Giovanni (Goddard Interactive Online Visualization ANd aNalysis Infrastructure) is a web-based remote sensing and model data visualization and analysis system developed by the Goddard Earth Sciences Data and Information Services Center (GES DISC). This web-based tool facilitates data discovery, exploration and analysis of large amount of global and regional data sets, covering atmospheric dynamics, atmospheric chemistry, hydrology, oceanographic, and land surface. Data analysis functions include Lat-Lon map, time series, scatter plot, correlation map, difference, cross-section, vertical profile, and animation etc. Visualization options enable comparisons of multiple variables and easier refinement. Recently, new features have been developed, such as interactive scatter plots and maps. The performance is also being improved, in some cases by an order of magnitude for certain analysis functions with optimized software. We are working toward merging current Giovanni portals into a single omnibus portal with all variables in one (virtual) location to help users find a variable easily and enhance the intercomparison capability

  9. Bridging the Gap Between Stewards and Creators

    DEFF Research Database (Denmark)

    Austin, Robert; Nolan, Richard L.

    2007-01-01

    of business innovation. After researching the movement of Internet and computing pioneers among various organizations during a period between the early 1960s and the mid-1990s, the authors identified two distinct personality types that are both vital to successful technological innovation--but whose mindsets...... employees, and their focus is on a grand vision and mission; they frequently view business concerns as secondary. According to the authors, conflict between stewards and creators is, to some extent, inevitable. However, when such conflict is managed poorly, the organization's capacity to innovate...... group always wins; (3) cultivate people who have credibility with both creators and stewards and can help resolve conflicts; (4) use peer review to more accurately evaluate creators' specialized technical work; (5) structure the innovation process so that creators produce tangible artifacts regularly...

  10. Organelle Structures: Bridging Strategy and Technological Processes

    Institute of Scientific and Technical Information of China (English)

    Rob; Dekkers

    2002-01-01

    The shifting requirements as imposed on operations ma nagement require adjusting and tailoring the organisational structure to meet ma rket demands. However, translating these requirements directly into hierarchical structure will not ensure the integration of processes across organisational un its and guarantee desirable performance. Therefore, management and management li terature wonders: · How should we connect processes to the external environment within a strategi c framework · Which organisationa...

  11. Inclusive design: Bridging theory and practice

    NARCIS (Netherlands)

    Cremers, A.H.M.; Neerincx, M.A.; Jong, J.G.M. de

    2013-01-01

    Large groups in society lack the necessary skills to be sufficiently self-reliant and are in need of personal assistance. These groups could be supported by information and information technology (ICT), but only if this technology is designed to fit their (cognitive) abilities. Inclusive design theo

  12. Xspect: bridging open hypermedia and XLink

    DEFF Research Database (Denmark)

    Christensen, B.G.; Hansen, F.A.; Bouvin, N.O.

    2003-01-01

    it to include another open hypermedia format, FOHM. The Xspect system, based on XSLT and Javascript, provides users with an interface to browse and merge linkbases. Xspect supports navigational hypermedia in the form of links inserted on the fly into Web pages, as well as guided tours presented as SVG. Xspect...

  13. Bridging the gap between farmers and consumers

    DEFF Research Database (Denmark)

    Bedoin, Florence; Kristensen, Troels; Noe, Egon

    2009-01-01

    The aim of this article is to explore how different quality dimensions (safety, aesthetics, ethics and rooted ness) are created in food networks; how these qualities are transferred until the consumers; and how this process is supported by the organisation of the food network. Our postulate is th...

  14. Kisspeptins: bridging energy homeostasis and reproduction

    DEFF Research Database (Denmark)

    Castellano, Juan M; Bentsen, Agnete H; Mikkelsen, Jens D;

    2010-01-01

    Body energy reserves and metabolic state are relevant modifiers of puberty onset and fertility; forms of metabolic stress ranging from persistent energy insufficiency to morbid obesity are frequently linked to reproductive disorders. The mechanisms for such a close connection between energy balan...

  15. Kisspeptins: bridging energy homeostasis and reproduction

    DEFF Research Database (Denmark)

    Castellano, Juan M; Bentsen, Agnete H; Mikkelsen, Jens D;

    2010-01-01

    of rapamycin) and Crtc1 (Creb1-regulated transcription coactivator-1) as putative mediators for leptin regulation of Kiss1 expression, as well as the identification of other potential metabolic modulators of kisspeptin signaling, such as ghrelin, neuropeptide Y (NPY) and melanin-concentrating hormone (MCH)....

  16. New sanitation : bridging cities and agriculture

    NARCIS (Netherlands)

    Zeeman, G.

    2012-01-01

    Nieuwe sanitatie maakt minder gebruik van schoon water, en hergebruikt grondstoffenThis inaugural lecture revolves around recovering raw materials such as phosphate, nitrogen, organic substances, energy and water from domestic waste and wastewater. If separated at source using less water, these mate

  17. Bridging the Linguistic and Affective Gaps

    DEFF Research Database (Denmark)

    Westbrook, Peter Nils; Henriksen, Birgit

    2011-01-01

    , namely: 1) to describe the informant’s motivation for taking an English course; 2) to compare her affective and perceived linguistic needs with her objective needs; 3) to follow her own language focus areas during the course; and 4) to identify any subjective or objective gains she achieved from......This paper reports on a small-scale case study which follows an experienced Danish university lecturer during a tailor-made, one-to-one language course to improve her English language skills for lecturing, consisting of a five-week cycle of observed English-medium lectures and subsequent language...... feedback sessions. The study also includes a structured, in-depth interview with the informant, which yields very specific and rich data about how one lecturer feels about teaching in English, the informant’s own learning focus and the outcomes of a short language course. The aims of the study are fourfold...

  18. Bridging Resilience Engineering and Human Reliability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ronald L. Boring

    2010-06-01

    There has been strong interest in the new and emerging field called resilience engineering. This field has been quick to align itself with many existing safety disciplines, but it has also distanced itself from the field of human reliability analysis. To date, the discussion has been somewhat one-sided, with much discussion about the new insights afforded by resilience engineering. This paper presents an attempt to address resilience engineering from the perspective of human reliability analysis (HRA). It is argued that HRA shares much in common with resilience engineering and that, in fact, it can help strengthen nascent ideas in resilience engineering. This paper seeks to clarify and ultimately refute the arguments that have served to divide HRA and resilience engineering.

  19. Bridging Physics and Biology Teaching through Modeling

    OpenAIRE

    Hoskinson, Anne-Marie; Couch, Brian A.; Zwickl, Benjamin M.; Hinko, Kathleen; Caballero, Marcos D.

    2013-01-01

    As the frontiers of biology become increasingly interdisciplinary, the physics education community has engaged in ongoing efforts to make physics classes more relevant to life sciences majors. These efforts are complicated by the many apparent differences between these fields, including the types of systems that each studies, the behavior of those systems, the kinds of measurements that each makes, and the role of mathematics in each field. Nonetheless, physics and biology are both sciences t...

  20. Bridging the gap between wikipedia and academia

    OpenAIRE

    Jemielniak, Dariusz; Aibar,Eduard

    2016-01-01

    In this opinion piece, we would like to present a short literature review of perceptions and reservations towards Wikipedia in academia, address the common questions about overall reliability of Wikipedia entries, review the actual practices of Wikipedia usage in academia, and conclude with possible scenarios for a peaceful coexistence. Because Wikipedia is a regular topic of JASIST publications (Lim, 2009; Meseguer-Artola, Aibar, Llados, Minguillon, & Lerga, 2015; Mesgari, Okoli, Mehdi, ...

  1. Mathematics and technologies: bridging diverse languages

    OpenAIRE

    Cabrita, Isabel

    2002-01-01

    One of the most challenging aspects faced by the formal education system in Portugal is the existence of an increasing community of immigrants from the so-called eastern countries and from the PALOP (countries whit Portuguese as their official language). Very little is known about how different aspects of their culture may interfere with formal education in Portugal. In particular, how a deeper knowledge about their characteristic mathematical know-how, in formal and informal contexts may hel...

  2. Bridging the Gap Between Economics and Ecology

    OpenAIRE

    Gem Castillo; Larry Leefers

    1998-01-01

    Economics and ecology are often presented as opposing disciplines. Both fields have strengths and weaknesses. A new transdisciplinary field, ecological economics, attempts to bring together the strengths of both disciplines with a vision for a sustainable future. In this paper, we focus on one particular concept championed by ecological economists, natural capital. In particular, our interest is on the institutionalization of this concept through the United Nation's Satellite System for ...

  3. Fuzzy Based Decision Support System for Condition Assessment and Rating of Bridges

    Science.gov (United States)

    Srinivas, Voggu; Sasmal, Saptarshi; Karusala, Ramanjaneyulu

    2016-06-01

    In this work, a knowledge based decision support system has been developed to efficiently handle the issues such as distress diagnosis, assessment of damages and condition rating of existing bridges towards developing an exclusive and robust Bridge Management System (BMS) for sustainable bridges. The Knowledge Based Expert System (KBES) diagnoses the distresses and finds the cause of distress in the bridge by processing the data which are heuristic and combined with site inspection results, laboratory test results etc. The coupling of symbolic and numeric type of data has been successfully implemented in the expert system to strengthen its decision making process. Finally, the condition rating of the bridge is carried out using the assessment results obtained from the KBES and the information received from the bridge inspector. A systematic procedure has been developed using fuzzy mathematics for condition rating of bridges by combining the fuzzy weighted average and resolution identity technique. The proposed methodologies and the decision support system will facilitate in developing a robust and exclusive BMS for a network of bridges across the country and allow the bridge engineers and decision makers to carry out maintenance of bridges in a rational and systematic way.

  4. Fuzzy Based Decision Support System for Condition Assessment and Rating of Bridges

    Science.gov (United States)

    Srinivas, Voggu; Sasmal, Saptarshi; Karusala, Ramanjaneyulu

    2016-09-01

    In this work, a knowledge based decision support system has been developed to efficiently handle the issues such as distress diagnosis, assessment of damages and condition rating of existing bridges towards developing an exclusive and robust Bridge Management System (BMS) for sustainable bridges. The Knowledge Based Expert System (KBES) diagnoses the distresses and finds the cause of distress in the bridge by processing the data which are heuristic and combined with site inspection results, laboratory test results etc. The coupling of symbolic and numeric type of data has been successfully implemented in the expert system to strengthen its decision making process. Finally, the condition rating of the bridge is carried out using the assessment results obtained from the KBES and the information received from the bridge inspector. A systematic procedure has been developed using fuzzy mathematics for condition rating of bridges by combining the fuzzy weighted average and resolution identity technique. The proposed methodologies and the decision support system will facilitate in developing a robust and exclusive BMS for a network of bridges across the country and allow the bridge engineers and decision makers to carry out maintenance of bridges in a rational and systematic way.

  5. Bridging User Requirements and Cultural Objects

    DEFF Research Database (Denmark)

    Hadzilias, Elias; Carugati, Andrea

    2009-01-01

    This chapter aims at defining a framework for the design of e-Government services on cultural heritage. Starting from an analysis of three cases on digitisation of different types of cultural objects the author highlights the problems existing in the creation of e-services on cultural heritage....... These cases show the existence of four key issues in the development of this kind of information systems: digitisation, requirements engineering, standardisation and interoperability. The proposed framework addresses these issues focusing on the user requirements and the cultural object representation....... Dynamic content exchange requires the use of a prescriptive framework for the development of cultural heritage websites. This chapter provides such a framework using observation from concrete applications and knowledge of information systems development methodologies....

  6. Bridging the Web and Digital Publishing

    NARCIS (Netherlands)

    Herman, I.; Gylling, M.

    2015-01-01

    Although using advanced Web technologies at their core, e-books represent a parallel universe to everyday Web documents. Their production workflows, user interfaces, their security, access, or privacy models, etc, are all distinct. There is a lack of a vision on how to unify Digital Publishing and t

  7. Bridging the Gap between Audiology and Education.

    Science.gov (United States)

    Razack, Zaim Riza

    1995-01-01

    This article examines issues related to the provision of educational audiological services that are sensitive to the needs of a diverse population. The focus is on paradigm shifts from traditional clinical audiology to classroom-based educational audiology and use of a cyclical reflective process. Critical components of courses offered at York…

  8. Heavy Vector Triplets: Bridging Theory and Data

    CERN Document Server

    Pappadopulo, Duccio; Torre, Riccardo; Wulzer, Andrea

    2014-01-01

    We introduce a model-independent strategy to study narrow resonances which we apply to a heavy vector triplet of the Standard Model (SM) group for illustration. The method is based on a simplified phenomenological Lagrangian which reproduces a large class of explicit models. Firstly, this allows us to derive robust model-independent phenomenological features and, conversely, to identify the peculiarities of different explicit realizations. Secondly, limits on cross-section times BR can be converted into bounds on a few relevant parameters in a fully analytic way, allowing for an interpretation in any given explicit model. Based on the available 8 TeV LHC analyses, we derive current limits and interpret them for vector triplets arising in weakly coupled (gauge) and strongly coupled (composite) extensions of the SM. We point out that a model-independent limit setting procedure must be based on purely on-shell quantities, like a cross-section times BR. Finite width effects altering the limits can be considerably...

  9. Railroad Bridges

    Data.gov (United States)

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

  10. Chromosome Bridges Maintain Kinetochore-Microtubule Attachment throughout Mitosis and Rarely Break during Anaphase.

    Science.gov (United States)

    Pampalona, Judit; Roscioli, Emanuele; Silkworth, William T; Bowden, Brent; Genescà, Anna; Tusell, Laura; Cimini, Daniela

    2016-01-01

    Accurate chromosome segregation during cell division is essential to maintain genome stability, and chromosome segregation errors are causally linked to genetic disorders and cancer. An anaphase chromosome bridge is a particular chromosome segregation error observed in cells that enter mitosis with fused chromosomes/sister chromatids. The widely accepted Breakage/Fusion/Bridge cycle model proposes that anaphase chromosome bridges break during mitosis to generate chromosome ends that will fuse during the following cell cycle, thus forming new bridges that will break, and so on. However, various studies have also shown a link between chromosome bridges and aneuploidy and/or polyploidy. In this study, we investigated the behavior and properties of chromosome bridges during mitosis, with the idea to gain insight into the potential mechanism underlying chromosome bridge-induced aneuploidy. We find that only a small number of chromosome bridges break during anaphase, whereas the rest persist through mitosis into the subsequent cell cycle. We also find that the microtubule bundles (k-fibers) bound to bridge kinetochores are not prone to breakage/detachment, thus supporting the conclusion that k-fiber detachment is not the cause of chromosome bridge-induced aneuploidy. Instead, our data suggest that while the microtubules bound to the kinetochores of normally segregating chromosomes shorten substantially during anaphase, the k-fibers bound to bridge kinetochores shorten only slightly, and may even lengthen, during anaphase. This causes some of the bridge kinetochores/chromosomes to lag behind in a position that is proximal to the cell/spindle equator and may cause the bridged chromosomes to be segregated into the same daughter nucleus or to form a micronucleus.

  11. Myocardial Bridges and their Relationship to the Anterior Interventricular Branch of the Left Coronary Artery

    Directory of Open Access Journals (Sweden)

    Lima Vanildo Júnior de Melo

    2002-01-01

    Full Text Available OBJECTIVE: To analyze the relationship between myocardial bridges and the anterior interventricular branch (anterior descending of the left coronary artery. METHODS: The study was carried out with postmortem material, and methods of dissection and observation were used. We assessed the perimeter of the anterior interventricular branch of the left coronary artery using a pachymeter, calculated its proximal and distal diameters in relation to the myocardial bridge, and also its diameter under the myocardial bridge in 30 hearts. We also observed the position of the myocardial bridge in relation to the origin of the anterior interventricular branch. RESULTS: The diameters of the anterior interventricular branch were as follows: the mean proximal diameter was 2.76±0.76 mm; the mean diameter under the myocardial bridge was 2.08±0.54 mm; and the mean distal diameter was 1.98±0.59 mm. In 33.33% (10/30 of the cases, the diameter of the anterior interventricular branch under the myocardial bridge was lower than the diameter of the anterior interventricular branch distal to the myocardial bridge. In 3.33% (1/30 of the cases, an atherosclerotic plaque was found in the segment under the myocardial bridge. The myocardial bridge was located in the middle third of the anterior interventricular branch in 86.66% (26/30 of the cases. CONCLUSION: Myocardial bridges are more frequently found in the middle third of the anterior interventricular branch of the left coronary artery. The diameter of the anterior interventricular branch of the left coronary artery under the myocardial bridge may be smaller than after the bridge. Myocardial bridges may not provide protection against the formation of atherosclerotic plaque inside the anterior interventricular branch of the left coronary artery.

  12. Chemical, electrochemical, and thermal bridges for transmission of OTEC power

    Energy Technology Data Exchange (ETDEWEB)

    Biederman, N.P.; Sinnott, J.; Talib, A.; Blazek, C.F.

    1978-01-01

    Chemical and electrochemical means of providing a ''bridge'' from an OTEC plant to an energy market offer a number of advantages over electric cable transmission. The most recent work done by the Institute of Gas Technology (IGT) on assessing various forms of chemical, electrochemical, and thermal energy carriers for OTEC plants is reported. These energy carriers were evaluated in terms of their overall technical feasibility and economic potential in the energy marketplace as means for augmenting conventional chemical fuels, providing peaking electric power, and as chemical feedstocks.

  13. Myocarditis in athlete and myocardial bridge:An innocent bystander?

    Institute of Scientific and Technical Information of China (English)

    Federico; Quaranta; Emanuele; Guerra; Fabio; Sperandii; Francesco; De; Santis; Fabio; Pigozzi; Leonardo; Calò; Paolo; Borrione

    2015-01-01

    Myocarditis is a bacterial or viral inflammatory disease,often unnoticed or misdiagnosed.Athletes with myocarditis must stop practicing their activity since International medical Literature described some cases of sudden death.In the present report,we describe a case of an asymptomatic,apparently healthy,competitive athletes,who was diagnosed a myocarditis and as incidental finding a myocardial bridging.We focused the attention on the importance of anamnesis,electrocardiogram and athletes’ entourage for the diagnosis of such insidious pathologies and we evaluated the follow up,focusing the attention on electrocardiogram changes as well as on restitution ad integrum and prognosis,especially for the athletes.

  14. Research development of digital maintenance and management system for long-span cable-stayed bridges

    Institute of Scientific and Technical Information of China (English)

    REN Yuan; HUANG Qiao; SUN Yong-ming

    2009-01-01

    Digital cable-stayed bridge maintenance and management system (DCBMS) was developed for the need of maintenance and management of long-span cable-stayed bridges. In this paper, the major functions and theoretical application of eight modules were systematically stated with the background of Harbin Songhua River cable-stayed bridge, which include data management module, inspection and measurement module, assessment module, finite element analysis module, disease diagnosis and prediction module, maintenance module, query module and help module. By analyzing and calculating the data from manual inspection database, basic database and health monitoring subsystem, DCBMS can accomplish the functions like life prediction, disease diagnosis, comprehensive assessment, maintenance and management of bridges. Therefore, the maintenance and management of long-span cable-stayed bridges can be made digital, professional and scientific. By running this system, a real-time and specific technical guidance can be provided for the maintainers and managers of longspan cable-stayed bridges.

  15. Pragmatism: A bridge between Anglo-American and Contintental Philosophy?

    OpenAIRE

    Grube, D.M.

    2003-01-01

    In this paper, I will restrict myself to interpreting certain features of Margolis’ rich argument. I will discuss only those features that have a direct bearing on his thesis that pragmatism wins the three-sided contest between Anglo-American Philosophy, continental philosophy and pragmatism and, as such, can serve as a bridge to span the divide between Anglo-American and continental philosophy. Two mottoes Margolis utilizes serve as the vantage point of my discussion, viz. ’natural but not n...

  16. Bridging the Gap between Crisis Response Operations and Systems

    CERN Document Server

    Khalil, Khaled M; Nazmy, Taymour T; Salem, Abdel-Badeeh M

    2009-01-01

    There exist huge problems in the current practice of crisis response operations. Response problems are projected as a combination of failure in communication, failure in technology, failure in methodology, failure of management, and finally failure of observation. In this paper we compare eight crisis response systems namely: DrillSim [2, 13], DEFACTO [12, 17], ALADDIN [1, 6], RoboCup Rescue [11, 15], FireGrid [3, 8, 18], WIPER [16], D-AESOP [4], and PLAN C [14]. Comparison results will disclose the cause of failure of current crisis response operations (the response gap). Based on comparison results; we provide recommendations for bridging this gap between response operations and systems.

  17. Bridging developmental systems theory and evolutionary psychology using dynamic optimization.

    Science.gov (United States)

    Frankenhuis, Willem E; Panchanathan, Karthik; Clark Barrett, H

    2013-07-01

    Interactions between evolutionary psychologists and developmental systems theorists have been largely antagonistic. This is unfortunate because potential synergies between the two approaches remain unexplored. This article presents a method that may help to bridge the divide, and that has proven fruitful in biology: dynamic optimization. Dynamic optimization integrates developmental systems theorists' focus on dynamics and contingency with the 'design stance' of evolutionary psychology. It provides a theoretical framework as well as a set of tools for exploring the properties of developmental systems that natural selection might favor, given particular evolutionary ecologies. We also discuss limitations of the approach.

  18. Cable Supported Bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    Cable supported bridges in the form of suspension bridges and cable-stayed bridges are distinguished by their ability to overcome large spans.The book concentrates on the synthesis of cable supported bridges, covering both design and construction aspects. The analytical part covers simple methods...... to quantify the different structural configurations and allows a preliminary optimization of the main structure.Included are the most recent advances in structural design, corrosion protection of cables, aerodynamic safety, and erection procedures....

  19. Building Bridges

    DEFF Research Database (Denmark)

    The report Building Bridges adresses the questions why, how and for whom academic audience research has public value, from the different points of view of the four working groups in the COST Action IS0906 Transforming Audiences, Transforming Societies – “New Media Genres, Media Literacy and Trust...

  20. Bridging the Gap: Adaptive Games and Student-Centered VLEs

    Science.gov (United States)

    Del Blanco, Ángel; Torrente, Javier; Moreno-Ger, Pablo; Fernández-Manjón, Baltasar

    The widely used e-learning technology is facing new challenges such as how to produce student-centered systems that can be adapted to the needs of each student. Those objectives should be met in a standard compliant way to simplify general adoption. In this context, educational videogames are proposed as an ideal medium to facilitate adaptation and tracking of the students’ performance for assessment purposes. However, there are still barriers between the gaming and e-learning worlds preventing their mutual interaction. In this paper we propose a middleware to bridge this gap, integrating adaptive educational videogames in e-learning environments with a special focus on the ongoing standardization efforts.

  1. Ship collisions against wind turbines, quays and bridge piers

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    2013-01-01

    Analytical procedures are presented for analysis of the external dynamics of ship collisions against bottom supported flexible as well as rigid offshore structures such as wind turbine structures, quays and bridge piers. Based on the principles of conservation of momentum and energy algebraic...... plays an important role for reduction of the structural damage. For gravity based foundations it is shown that provided some limited foundation displacements can be allowed then the requirements to the shear sliding force capacity can be reduced significantly. © 2013 Taylor & Francis Group....

  2. Conductive bridging random access memory—materials, devices and applications

    Science.gov (United States)

    Kozicki, Michael N.; Barnaby, Hugh J.

    2016-11-01

    We present a review and primer on the subject of conductive bridging random access memory (CBRAM), a metal ion-based resistive switching technology, in the context of current research and the near-term requirements of the electronics industry in ultra-low energy devices and new computing paradigms. We include extensive discussions of the materials involved, the underlying physics and electrochemistry, the critical roles of ion transport and electrode reactions in conducting filament formation and device switching, and the electrical characteristics of the devices. Two general cation material systems are given—a fast ion chacogenide electrolyte and a lower ion mobility oxide ion conductor, and numerical examples are offered to enhance understanding of the operation of devices based on these. The effect of device conditioning on the activation energy for ion transport and consequent switching speed is discussed, as well as the mechanisms involved in the removal of the conducting bridge. The morphology of the filament and how this could be influenced by the solid electrolyte structure is described, and the electrical characteristics of filaments with atomic-scale constrictions are discussed. Consideration is also given to the thermal and mechanical environments within the devices. Finite element and compact modelling illustrations are given and aspects of CBRAM storage elements in memory circuits and arrays are included. Considerable emphasis is placed on the effects of ionizing radiation on CBRAM since this is important in various high reliability applications, and the potential uses of the devices in reconfigurable logic and neuromorphic systems is also discussed.

  3. Bridged bis-BODIPYs: their synthesis, structures and properties.

    Science.gov (United States)

    Kesavan, Praseetha E; Das, Sudipta; Lone, Mohsin Y; Jha, Prakash C; Mori, Shigeki; Gupta, Iti

    2015-10-21

    A series of bis-BODIPYs 1-6 bridged via thiophene, furan, N-alkylcarbazole, triphenyl-amine, para- and meta-phenylene groups have been synthesized and characterized by various spectroscopic techniques. The change in the spectroscopic properties of bis-BODIPYs upon varying the size of spacers was studied. X-ray crystal structures of three bis-BODIPYs containing triphenylamine, para- and meta-phenylene bridges were solved. Intermolecular C(H)π and ππ stacking interactions were observed in solid state structures of three bis-BODIPYs. The dihedral angles between the spacer unit and two boron-dipyrrin units were lower in all three compounds as compared to their corresponding monomers. This suggests increased interactions between the two boron-dipyrrin units in molecules which are in turn reflected in the anodic shifts in their reduction potentials. DFT studies indicated effective electronic interactions between spacers and two boron dipyrrin units in all the bis-BODIPYs. The calculated HOMO-LUMO gap was found to be lower for bis-BODIPY having bulky carbazole spacers and higher for bis-BODIPY having smaller furan spacers. Changing the spacer size clearly affected the spectroscopic properties of the bis-BODIPYs and red shifted absorption and emission maxima were observed for bis-BODIPYs with furan and thiophene spacers as compared to bis-BODIPYs with phenylene or bulky aromatic spacers. PMID:26373792

  4. PERCENTAGE INCIDENCE, MORPHOLOGY AND MORPHOMETRY OF MYOCARDIAL BRIDGES: A CADAVERIC STUDY

    Directory of Open Access Journals (Sweden)

    Sujatha. M

    2015-06-01

    Full Text Available Introduction: Myocardial bridging is the term used when a segment of major epicardial coronary artery runs intramuscularly under the tunnel formed by fibers of myocardium that bridges instead of it’s normal or routine epicardial path. In the literature there are varying reports on clinical implications of myocardial bridges from protection against atherosclerosis to myocardial ischemia, as well as leading to infarction and sudden cardiac death. Materials and Methods: 150 adult formalin fixed human hearts which were available in the department of Anatomy and Forensic Medicine, S.V.Medical College, Tirupati, Andhra Pradesh, India. These hearts were dissected and observed for the presence, location, type, number and direction of myocardial bridges and their association with coronary dominance. With the help of digital calipers morphometric parameters (length, width& thickness of myocardial bridges and length of blood vessel underneath the myocardial bridge were measured, noted and photographs were taken. Results: The overall incidence of myocardial bridges was 20.6%( 31/150. Among these 18.6% (28/31 were on left anterior descending (LAD artery and 2% (03/31 were on posterior interventricular (PIV artery. The direction of muscle fibers in the bridges were oblique to the direction of the coronary vessels in majority of cases. Length, width and thickness of myocardial bridges were in the range of 12 – 69.7mm, 3.74 – 8.6mm and1.3 – 3.87mmrespectively. Conclusions: Myocardial bridges may be associated with wide range of clinical problems. Contraction of myocardial bridge may results in vascular compression and myocardial ischemia. Knowledge on morphology and morphometric details of myocardial bridges facilitates cardiologists in diagnosis, planning therapeutic strategies and prognostic predictions.

  5. GPS Dynamic Monitoring Experiment and Result Analysis of Long-Span Cable-Stayed Bridge

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    For the sake of timely appraising the working condition of the bridge, measuring the dynamic characteristics of the bridge structure is very important and necessary. A GPS dynamic monitoring test was carried out in the Wuhan Baishazhou Bridge, which is one of the longest span cable-stayed bridges having been built in China. This paper introduces the experimental implementing scheme and data processing method. The vibration characteristics of the middle span of cable-stayed bridge are availably obtained by use of the spectral analytic approach. The measuring results are very identical to the theoretical designed values. The research demonstrates that, with GPS receiver of the high sampling rate and suitable data processing method, the vibration characteristics of the bridge structure can be determined with high accuracy.

  6. On the Performance of Super-Long Integral Abutment Bridges: Parametric Analyses and Design Optimization

    OpenAIRE

    Lan, Cheng

    2012-01-01

    The concept of "integral abutment bridge" has recently become a topic of remarka-ble interest among bridge engineers, not only for newly built bridges but also during refurbishment processes. The system constituted by the substructure and the superstructure can achieve a composite action responding as a single structural unit; the elimination of expansion joint and bearings on the abutments, greatly reduce the construction and maintenance costs. To maximize the benefits from integral abutment...

  7. Experimental and Numerical Analysis of Bridge Response due to Modular Combination Vehicle Systems

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Bang, R.

    2004-01-01

    paper investigates the dynamic amplification of a minor Danish highway bridge due to passage of such modular combination vehicle systems. A simulation model for a typical Danish highway bridge and the two different vehicles is established. The two different vehicles are a standard 48.8 ton articulated...... vehicle and a 60 ton vehicle consisting of a lorry and semi-trailer carried by a dolly. The dynamic parameters of the vehicles and the modal parameters of the bridge are estimated from measurements obtained for different passage situations of the two vehicles. Results show a good agreement between...... simulated and measured bridge acceleration response and dynamic amplification factors....

  8. Integrated system of structural health monitoring and intelligent management for a cable-stayed bridge.

    Science.gov (United States)

    Chen, Bin; Wang, Xu; Sun, Dezhang; Xie, Xu

    2014-01-01

    It is essential to construct structural health monitoring systems for large important bridges. Zhijiang Bridge is a cable-stayed bridge that was built recently over the Hangzhou Qiantang River (the largest river in Zhejiang Province). The length of Zhijiang Bridge is 478 m, which comprises an arched twin-tower space and a twin-cable plane structure. As an example, the present study describes the integrated system of structural health monitoring and intelligent management for Zhijiang Bridge, which comprises an information acquisition system, data management system, evaluation and decision-making system, and application service system. The monitoring components include the working environment of the bridge and various factors that affect bridge safety, such as the stress and strain of the main bridge structure, vibration, cable force, temperature, and wind speed. In addition, the integrated system includes a forecasting and decision-making module for real-time online evaluation, which provides warnings and makes decisions based on the monitoring information. From this, the monitoring information, evaluation results, maintenance decisions, and warning information can be input simultaneously into the bridge monitoring center and traffic emergency center to share the monitoring data, thereby facilitating evaluations and decision making using the system.

  9. Integrated System of Structural Health Monitoring and Intelligent Management for a Cable-Stayed Bridge

    Directory of Open Access Journals (Sweden)

    Bin Chen

    2014-01-01

    Full Text Available It is essential to construct structural health monitoring systems for large important bridges. Zhijiang Bridge is a cable-stayed bridge that was built recently over the Hangzhou Qiantang River (the largest river in Zhejiang Province. The length of Zhijiang Bridge is 478 m, which comprises an arched twin-tower space and a twin-cable plane structure. As an example, the present study describes the integrated system of structural health monitoring and intelligent management for Zhijiang Bridge, which comprises an information acquisition system, data management system, evaluation and decision-making system, and application service system. The monitoring components include the working environment of the bridge and various factors that affect bridge safety, such as the stress and strain of the main bridge structure, vibration, cable force, temperature, and wind speed. In addition, the integrated system includes a forecasting and decision-making module for real-time online evaluation, which provides warnings and makes decisions based on the monitoring information. From this, the monitoring information, evaluation results, maintenance decisions, and warning information can be input simultaneously into the bridge monitoring center and traffic emergency center to share the monitoring data, thereby facilitating evaluations and decision making using the system.

  10. PERCENTAGE INCIDENCE, MORPHOLOGY AND MORPHOMETRY OF MYOCARDIAL BRIDGES: A CADAVERIC STUDY

    OpenAIRE

    Sujatha. M; T. Jayachandra Pillai; L. Anandakumar; V. Subhadra Devi

    2015-01-01

    Introduction: Myocardial bridging is the term used when a segment of major epicardial coronary artery runs intramuscularly under the tunnel formed by fibers of myocardium that bridges instead of it’s normal or routine epicardial path. In the literature there are varying reports on clinical implications of myocardial bridges from protection against atherosclerosis to myocardial ischemia, as well as leading to infarction and sudden cardiac death. Materials and Methods: 150 adult formalin fix...

  11. 涵洞式渡槽结构理论分析研究%Analytical in estigation of reinforced concrete culvert aqueduct

    Institute of Scientific and Technical Information of China (English)

    陈爱玖; 解伟; 赵中极; 赵平

    2001-01-01

    利用三维有限元对涵洞式渡槽进行结构分析,根据结构特征、地质条件和结构材料的力学参数,对结构进行分析,得到应力和变形规律,为渡槽设计提供了可靠依据.%The structure of culvert aqueduct was analyzed in details by finite element. Based on structural characteristics,geological condition and mechanical paramenters of structure material, the equeduct is simplified to a three dimensional liner body. The ultimate bearing limit states of aqueduct structure is analyzed. The results obtained in this paper provied reliable basis for aqueduct design.

  12. Characterisation of a Selection of AC and DC Resistance Bridges for Standard Platinum Resistance Thermometry

    Science.gov (United States)

    Pearce, J. V.; Gray, J.; Veltcheva, R. I.

    2016-11-01

    Accurate resistance bridges are used to measure the ratio between the resistance of standard platinum resistance thermometers and a reference (standard) resistor at the level of microkelvin in temperature terms and as such play a critical role in the realisation and dissemination of the ITS-90. For AC bridges, the ratio test unit has been available for some time, and for both AC and DC bridges, the increasing availability of resistance bridge calibrators based on combinatorial calibration has increased the ease with which the accuracy and linearity of resistance bridges may be determined, under conditions which provide a realistic representation of the actual measurement set-up. In this study, the performance of 14 resistance bridges, which were available for testing at NPL, consisting of a range of manufacturers and types, has been evaluated and expressed in terms of the standard deviation of the bridge errors over a given range of ratios, namely s. In general, the bridges are found to comply with the manufacturers' specifications. The uncertainty of s has also been determined using Monte Carlo techniques and is found to be of the order of 10 % of s for most bridge types.

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

    Science.gov (United States)

    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.

  14. Identification and characterization of RBM44 as a novel intercellular bridge protein.

    Directory of Open Access Journals (Sweden)

    Tokuko Iwamori

    Full Text Available Intercellular bridges are evolutionarily conserved structures that connect differentiating germ cells. We previously reported the identification of TEX14 as the first essential intercellular bridge protein, the demonstration that intercellular bridges are required for male fertility, and the finding that intercellular bridges utilize components of the cytokinesis machinery to form. Herein, we report the identification of RNA binding motif protein 44 (RBM44 as a novel germ cell intercellular bridge protein. RBM44 was identified by proteomic analysis after intercellular bridge enrichment using TEX14 as a marker protein. RBM44 is highly conserved between mouse and human and contains an RNA recognition motif of unknown function. RBM44 mRNA is enriched in testis, and immunofluorescence confirms that RBM44 is an intercellular bridge component. However, RBM44 only partially localizes to TEX14-positive intercellular bridges. RBM44 is expressed most highly in pachytene and secondary spermatocytes, but disappears abruptly in spermatids. We discovered that RBM44 interacts with itself and TEX14 using yeast two-hybrid, mammalian two-hybrid, and immunoprecipitation. To define the in vivo function of RBM44, we generated a targeted deletion of Rbm44 in mice. Rbm44 null male mice produce somewhat increased sperm, and show enhanced fertility of unknown etiology. Thus, although RBM44 localizes to intercellular bridges during meiosis, RBM44 is not required for fertility in contrast to TEX14.

  15. Effects of CFRP Strengthening on Dynamic and Fatigue Responses of Composite Bridge

    Directory of Open Access Journals (Sweden)

    Kittisak Kuntiyawichai

    2014-01-01

    Full Text Available This paper investigates the effect of CFRP strengthening on dynamic and fatigue responses of composite bridge using finite element program ABAQUS. Dynamic and fatigue responses of composite bridge due to truck load based on AASHTO standard are investigated. Two types of CFRP strengthening techniques, CFRP sheets and CFRP deck, are applied to both the damaged and undamaged bridges. For the case of damaged bridge, two through-thickness crack sizes, 3 mm and 6 mm in depth, are assumed at midspan of the steel girders. Furthermore, effects of the number of steel girders on the dynamic and fatigue responses are also considered. The results show that the maximum responses of composite bridges occur for dual lane cases. By using CFRP as a strengthening material, the maximum stress and deflection of the steel girders reduce and consequently increase the fatigue life of the girders. After introducing initial crack into the steel girders of the composite bridges, the fatigue life of the bridges is dramatically reduced. However, the overall performance of the damaged composite bridge can be improved by using CFRP, albeit with less effectiveness. Therefore, if cracks are found, steel welding must be performed before strengthening the composite bridge by CFRP.

  16. Structural health monitoring of a railway truss bridge using vibration-based and ultrasonic methods

    International Nuclear Information System (INIS)

    This paper presents results of in situ investigation of a railway truss bridge in the context of structural health monitoring (SHM). Three experimental methods are examined. Dynamic responses of the bridge recorded by strain gauges are confronted with alternative ways of acquisition using piezoelectric patch sensors and ultrasonic probeheads. All types of sensors produce similar output. Also the corresponding responses of the numerical model of the bridge match experimental data

  17. Bridge data – what do we collect and how do we use it?

    OpenAIRE

    Bennetts, John; Vardanega, Paul; Taylor, Colin; Denton, Stephen

    2016-01-01

    The organisations responsible for managing bridge assets in the United Kingdom collect large quantities of data on their bridges. A primary aspiration in the collection of asset data is that it can be processed into useful information that can inform decisions about future management of structures and enhance industry best practice. To enable this, bridge managers must take care to specify appropriate parameters to be recorded, in conjunction with a practical recording interval. In addition, ...

  18. Sustainable Bridge Procurement Considering Life-Cycle Cost, Life-Cycle Assessment and Aesthetics

    DEFF Research Database (Denmark)

    Safi, Mohammed; Du, Guangli; Simonsson, Peter

    2016-01-01

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

  19. The novel generating algorithm and properties of hybrid-P-ary generalized bridge functions

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In this paper, we develop novel non-sine functions, named hybrid-P-ary generalized bridge functions, based on the copy and shift methods. The generating algorithm of hybrid-P-ary generalized bridge functions is introduced based on the hybrid-P-ary generalized Walsh function's copy algorithm. The main property, product property, is also discussed. This function may be viewed as the generalization of the theory of bridge functions. And a lot of non-sine orthogonal functions are the special subset of these novel functions. The hybrid-P-ary generalized bridge functions can be used to search many unknown non-sine functions by defining different parameters.

  20. Bridge ice accretion and de- and anti-icing systems: A review

    DEFF Research Database (Denmark)

    Kleissl, Kenneth; Georgakis, Christos

    2010-01-01

    Blocks of ice or snow falling from bridge members can cause traffic accidents, direct damages to passing vehicles, and generally place human safety at risk. Consequently, the lack of successful de- or anti-icing measures may result in bridge closure, which leads to traffic hindrance that can...

  1. Taizhou Yangtze River Bridge

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

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

  2. Random vibration analysis of train-bridge under track irregularities and traveling seismic waves using train-slab track-bridge interaction model

    Science.gov (United States)

    Zeng, Zhi-Ping; Zhao, Yan-Gang; Xu, Wen-Tao; Yu, Zhi-Wu; Chen, Ling-Kun; Lou, Ping

    2015-04-01

    The frequent use of bridges in high-speed railway lines greatly increases the probability that trains are running on bridges when earthquakes occur. This paper investigates the random vibrations of a high-speed train traversing a slab track on a continuous girder bridge subjected to track irregularities and traveling seismic waves by the pseudo-excitation method (PEM). To derive the equations of motion of the train-slab track-bridge interaction system, the multibody dynamics and finite element method models are used for the train and the track and bridge, respectively. By assuming track irregularities to be fully coherent random excitations with time lags between different wheels and seismic accelerations to be uniformly modulated, non-stationary random excitations with time lags between different foundations, the random load vectors of the equations of motion are transformed into a series of deterministic pseudo-excitations based on PEM and the wheel-rail contact relationship. A computer code is developed to obtain the time-dependent random responses of the entire system. As a case study, the random vibration characteristics of an ICE-3 high-speed train traversing a seven-span continuous girder bridge simultaneously excited by track irregularities and traveling seismic waves are analyzed. The influence of train speed and seismic wave propagation velocity on the random vibration characteristics of the bridge and train are discussed.

  3. Occupational health problems of bridge and tunnel officers.

    Science.gov (United States)

    Herbert, R; Szeinuk, J; O'Brien, S

    2001-01-01

    Bridge and tunnel officers (BTOs) sustain potential exposure to a number of physical, chemical, and work-organizational factors. They are at risk for both fatal and non-fatal occupational injuries due to moving vehicles, workplace violence, vehicular fires, and physical hazards, such as slippery walking surfaces due to oil or ice on roadways. This chapter describes the spectrum of occupational injuries and illnesses which may be seen in BTOs, focusing on: 1) vehicular exhaust and air pollution, 2) ergonomic hazards, 3) job strain, 4) noise, 5) blood-borne pathogens, 6) chemicals used in road work and maintenance (e.g., lead-based paint), and 7) with the recent advent of electronic traffic sensors, microwave radiation. Special emphasis is given to respiratory disease and cardiovascular disease. Finally, some recommendations for focused health surveillance and preventive efforts in this population are made. PMID:11107224

  4. A bridge between conceptual frameworks sciences, society and technology studies

    CERN Document Server

    2015-01-01

    This book analyzes scientific problems within the history of physics, engineering, chemistry, astronomy and medicine, correlated with technological applications in the social context. When and how is tension between disciplines explicitly practised? What is the conceptual bridge between science researches and the organization of technological researches in the development of  industrial applications?  The authors explain various ways in which the sciences allowed advanced modelling on the one hand, and the development of new technological ideas on the other hand. An emphasis on the role played by mechanisms, production methods and instruments bestows a benefit on historical and scientific discourse: theories, institutions, universities, schools for engineers, social implications as well.  Scholars from different traditions discuss the emerging style of thinking in methodology and, in theoretical perspective, aim to gather and re-evaluate the current thinking on this subject. It brings together contribution...

  5. Bridging emotion theory and neurobiology through dynamic systems modeling.

    Science.gov (United States)

    Lewis, Marc D

    2005-04-01

    Efforts to bridge emotion theory with neurobiology can be facilitated by dynamic systems (DS) modeling. DS principles stipulate higher-order wholes emerging from lower-order constituents through bidirectional causal processes--offering a common language for psychological and neurobiological models. After identifying some limitations of mainstream emotion theory, I apply DS principles to emotion-cognition relations. I then present a psychological model based on this reconceptualization, identifying trigger, self-amplification, and self-stabilization phases of emotion-appraisal states, leading to consolidating traits. The article goes on to describe neural structures and functions involved in appraisal and emotion, as well as DS mechanisms of integration by which they interact. These mechanisms include nested feedback interactions, global effects of neuromodulation, vertical integration, action-monitoring, and synaptic plasticity, and they are modeled in terms of both functional integration and temporal synchronization. I end by elaborating the psychological model of emotion-appraisal states with reference to neural processes.

  6. Medical immunology: two-way bridge connecting bench and bedside.

    Science.gov (United States)

    Rijkers, Ger T; Damoiseaux, Jan G M C; Hooijkaas, Herbert

    2014-12-01

    Medical immunology in The Netherlands is a laboratory specialism dealing with immunological analyses as well as pre- and post-analytical consultation to clinicians (clinical immunologists and other specialists) involved in patients with immune mediated diseases. The scope of medical immunology includes immunodeficiencies, autoimmune diseases, allergy, transfusion and transplantation immunology, and lymphoproliferative disorders plus the monitoring of these patients. The training, professional criteria, quality control of procedures and laboratories is well organized. As examples of the bridge function of medical immunology between laboratory (bench) and patient (bedside) the contribution of medical immunologists to diagnosis and treatment of primary immunodeficiency diseases (in particular: humoral immunodeficiencies) as well as autoantibodies (anti-citrullinated proteins in rheumatoid arthritis) are given.

  7. Practical applications of asset management and comakership business models for FRP bridges

    NARCIS (Netherlands)

    Sebastian, R.

    2012-01-01

    Fibre Reinforced Polymer (FRP) material and the associated technologies for bridge construction and refurbishment have been proven to be durable and sustainable. Much research and a number of recent projects have demonstrated that FRP bridges can also be cost-effective, provided that the cost and be

  8. Campus suicide prevention: bridging paradigms and forging partnerships.

    Science.gov (United States)

    Drum, David J; Denmark, Adryon Burton

    2012-01-01

    Colleges and universities are increasingly recognizing the need to expand suicide-prevention efforts beyond the standard, clinical-intervention paradigm of suicide prevention, which relies on referral to, and treatment by, mental health services. These services frequently struggle, however, to provide effective, comprehensive care. After reviewing findings that support the need to adopt a broader, problem-focused paradigm, the article provides a framework for bridging this paradigm with the clinical-intervention approach and for conceptualizing a full continuum of preventive interventions. For each level of intervention (ranging from the individual to the ecological), we describe the goals and methods used, and provide examples to illustrate the role of psychiatrists and other campus mental health providers in the collaborative partnerships that must form to support a comprehensive, campus-wide suicide-prevention strategy.

  9. Bridging the gap: strategies to integrate classroom and clinical learning.

    Science.gov (United States)

    Flood, Lisa Sue; Robinia, Kristi

    2014-08-01

    Nursing students often feel their classroom (didactic) learning and clinical (practice) experiences are disconnected which can lead to a rejection of academe and dissatisfaction with the profession. This classroom/clinical divide may be exacerbated because of the increased use of part-time clinical faculty, who are often isolated from their didactic peers. If clinical faculty, either novice or experienced, are disconnected from didactic faculty, is it any wonder students feel their learning is fragmented? The purpose of this paper is to discuss strategies to help bridge the gap between didactic and clinical learning. Specific integration strategies for faculty are presented using examples from a baccalaureate adult nursing didactic course and its related clinical course. The role of a clinical coordinator in facilitating course integration and support for part-time clinical faculty is described. Ideas for using technology to enhance learning and suggestions to promote socialization to decrease faculty isolation are also discussed. PMID:24674949

  10. Six new projects will bridge gap between CERN and society

    CERN Multimedia

    Anaïs Rassat, Knowledge Transfer Group

    2016-01-01

    Knowledge Transfer Fund awarded over six hundred thousand Swiss francs to six projects in 2016.   Computer racks at the CERN Data Centre, the heart of CERN’s entire scientific, administrative, and computing infrastructure. CERN has awarded funding to six new projects with the aim to bridge the gap between technology and society. Over 600,000 CHF (€ 542,766) of capital was granted through its competitive Knowledge Transfer Fund (KT Fund). The fund is issued as part of CERN’s goal to maximize its overall impact on society. The selected projects cover new applications for CERN technology in a broad range of fields beyond high-energy physics, ranging from cancer diagnostics and aerospace applications, to next-generation cloud computing, radiation safety, and digital preservation. The technologies were developed at CERN as part of the variety of high-energy physics needs, and arise from several research departments: Engineering, Information Technology, Be...

  11. Community garden: A bridging program between formal and informal learning

    Directory of Open Access Journals (Sweden)

    Ranjan Datta

    2016-12-01

    Full Text Available Community garden activities can play a significant role in bridging formal and informal learning, particularly in urban children’s science and environmental education. It promotes relational methods of learning, discussing, and practicing that will integrate food security, social interactions, community development, environmental activism, and cultural integration. Throughout the last five years of my community garden activities, I have learned that community garden-based practices adhere to particular forms of agency: embracing diversity, sharing power, and trust building as a part of everyday learning. My auto-ethnographic study provides valuable insights for environmental educators whose goals include, incorporating ethnic diversity as well as engaging children in research, ultimately leading to community action.

  12. Hybrid Supramolecular and Colloidal Hydrogels that Bridge Multiple Length Scales**

    Science.gov (United States)

    Janeček, Emma-Rose; McKee, Jason R; Tan, Cindy S Y; Nykänen, Antti; Kettunen, Marjo; Laine, Janne; Ikkala, Olli; Scherman, Oren A

    2015-01-01

    Hybrid nanocomposites were constructed based on colloidal nanofibrillar hydrogels with interpenetrating supramolecular hydrogels, displaying enhanced rheological yield strain and a synergistic improvement in storage modulus. The supramolecular hydrogel consists of naphthyl-functionalized hydroxyethyl cellulose and a cationic polystyrene derivative decorated with methylviologen moieties, physically cross-linked with cucurbit[8]uril macrocyclic hosts. Fast exchange kinetics within the supramolecular system are enabled by reversible cross-linking through the binding of the naphthyl and viologen guests. The colloidal hydrogel consists of nanofibrillated cellulose that combines a mechanically strong nanofiber skeleton with a lateral fibrillar diameter of a few nanometers. The two networks interact through hydroxyethyl cellulose adsorption to the nanofibrillated cellulose surfaces. This work shows methods to bridge the length scales of molecular and colloidal hybrid hydrogels, resulting in synergy between reinforcement and dynamics. PMID:25772264

  13. The Impact of Community Bonding and Bridging Social Capital on Educational Performance in Israel

    Science.gov (United States)

    Menahem, Gila

    2011-01-01

    The study examines two issues of the relationship between social capital and educational performance: the different effects of bridging and bonding social capital on urban educational performance and the contextual effects of social capital. The main argument states that bonding and bridging social capital are differently related to educational…

  14. Apical aneurysm and myocardial bridging in a patient with hypertrophic cardiomyopathy: association or consequence of the myocardial bridging?

    Science.gov (United States)

    Foucault, Anthony; Hilpert, Loic; Hédoire, Francois; Saloux, Eric; Gomes, Sophie; Pellissier, Arnaud; Scanu, Patrice; Champ-Rigot, Laure; Milliez, Paul

    2012-01-01

    The identification of high-risk patients with hypertrophic cardiomyopathy (HC) for primary prevention of sudden cardiac death (SCD) remains a challenging issue, since major risk factors sometimes lack specificity. We report the case of a patient with HC and association of apical aneurysm and myocardial bridging who had been initially not implanted because she had only one major risk factor. She subsequently experienced a sustained ventricular tachycardia that finally motivated the implantation. We conclude that it is never an easy decision to implant a preventive implantable cardioverter-defibrillator (ICD). Nevertheless, additional criteria for a better selection of patients who would benefit from an ICD implant are certainly useful.

  15. Collaborative Professional Development in Chemistry Education Research: Bridging the Gap between Research and Practice

    Science.gov (United States)

    Szteinberg, Gabriela; Balicki, Scott; Banks, Gregory; Clinchot, Michael; Cullipher, Steven; Huie, Robert; Lambertz, Jennifer; Lewis, Rebecca; Ngai, Courtney; Weinrich, Melissa; Talanquer, Vicente; Sevian, Hannah

    2014-01-01

    Professional development that bridges gaps between educational research and practice is needed. However, bridging gaps can be difficult because teachers and educational researchers often belong to different Communities of Practice, as their activities, goals, and means of achieving those goals often differ. Meaningful collaboration among teachers…

  16. Heterogeneous ice nucleation: bridging stochastic and singular freezing behavior

    Directory of Open Access Journals (Sweden)

    D. Niedermeier

    2011-01-01

    Full Text Available Heterogeneous ice nucleation, a primary pathway for ice formation in the atmosphere, has been described alternately as being stochastic, in direct analogy with homogeneous nucleation, or singular, with ice nuclei initiating freezing at deterministic temperatures. We present an idealized model that bridges these stochastic and singular descriptions of heterogeneous ice nucleation. This "soccer ball" model treats statistically similar particles as being covered with surface sites (patches of finite area characterized by different nucleation barriers, but with each surface site following the stochastic nature of ice embryo formation. The model provides a phenomenological explanation for seemingly contradictory experimental results obtained in our research groups. We suggest that ice nucleation is fundamentally a stochastic process but that for realistic atmospheric particle populations this process can be masked by the heterogeneity of surface properties. Full evaluation of the model will require experiments with well characterized ice nucleating particles and the ability to vary both temperature and waiting time for freezing.

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

    OpenAIRE

    D'Alessandro, Kacie Caple

    2013-01-01

    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 desi...

  18. Development, analysis, and control of the inductor-converter bridge

    International Nuclear Information System (INIS)

    The inductor-converter bridge (ICB) is a solid state dc-ac-dc power converter system for bidirectional, controllable, energy transfer between two high Q magnet coils. The ICB is suitable for supplying large pulsed power to such magnets as the superconducting equilibrium field (EF) coil of the proposed tokamak power reactors, from another superconducting energy storage coil. This report presents work on the analysis and control of the ICB system. The process of energy transfer between the coils is explained on the basis of a simple one line equivalent circuit. This circuit is the topological dual of the one line diagram of the nonsalient pole synchoronous generator, connected to the infinite bus through its synchronous reactance. The changes in the average power, average coil currents, and voltages, as functions of time, are calculated by the conventional Fourier method of analysis

  19. 23 CFR 650.411 - Procedures for bridge replacement and rehabilitation projects.

    Science.gov (United States)

    2010-04-01

    ... Rehabilitation Program § 650.411 Procedures for bridge replacement and rehabilitation projects. (a) Consideration... the State to the Secretary in accordance with 23 CFR part 630, subpart A Federal-Aid Programs... 23 Highways 1 2010-04-01 2010-04-01 false Procedures for bridge replacement and...

  20. Tuning interaction in dinuclear ruthenium complexes : HOMO versus LUMO mediated superexchange through azole and azine bridges

    NARCIS (Netherlands)

    Browne, Wesley; Hage, R; Vos, Johannes G.

    2006-01-01

    In this review the interaction between metal centers in dinuclear complexes based on azole and azine containing bridging ligands is reviewed. The focus of the review is on the manner in which the interaction pathway can be manipulated by variations in the nature of both the direct bridging unit and

  1. Bridging Home: Building Relationships between Immigrant and Long-Time Resident Youth

    Science.gov (United States)

    Dryden-Peterson, Sarah

    2010-01-01

    Background: There is rising evidence that relationships that bridge between immigrants and long-time residents are critical to immigrant integration and to the overall heath of communities. The processes by which this bridging social capital is built are not well understood. Schools in new immigrant destinations, as spaces in which diverse youth…

  2. Synthesis of bridged diketopiperazines by using the persistent radical effect and a formal synthesis of bicyclomycin.

    Science.gov (United States)

    Amatov, Tynchtyk; Pohl, Radek; Císařová, Ivana; Jahn, Ullrich

    2015-10-01

    A conceptually new and unified approach to diverse bridged diketopiperazines (DKPs) with widely variable ring sizes was developed by taking advantage of the persistent radical effect. This method enables synthesis of the core structures of bridged DKP alkaloids and was applied to a formal synthesis of the antibiotic bicyclomycin.

  3. The Structure and Mechanical Properties of Bridge Steel Weldings With Glass-Steel Liners

    Science.gov (United States)

    Muzalev, V. N.; Semukhin, B. S.; Danilov, V. I.

    2016-04-01

    A new technology is developed for welding multi-span bridge constructions. The mechanical properties and structure of the low-carbon bridge steel welds have been studied. The welding parameters and application of steel-glass liners provide for long-term service of steel constructions in conformity with the welding industry specifications.

  4. Economical bridge solutions based on innovative composite dowels and integrated abutments ecobridge

    CERN Document Server

    Băncilă, Radu

    2015-01-01

    This book is an outcome of the research project “ECOBRIDGE – Demonstration of ECOnomical BRIDGE solutions based on innovative composite dowels and integrated abutments – RFCS – CT 2010-00024”, which has been co-funded by the Research Fund for Coal and Steel (R.F.C.S.) of the European Community. The main topics of the book are the following: design of integral bridges, innovative composite dowels for the shear transmission, construction of bridges, structural analysis of bridges and monitoring. The book joins the technical experience and the contributions of the involved research partners. The technical content of all the papers is present-day in the field of the design, construction and monitoring of innovative composite bridges. The efficient design and construction improve and consolidate the market position of steel construction and steel producing industry. In addition, the advanced forms of construction are contributing to savings in material and energy consumption for the structure during prod...

  5. Dynamic test and finite element model updating of bridge structures based on ambient vibration

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The dynamic characteristics of bridge structures are the basis of structural dynamic response and seismic analysis,and are also an important target of health condition monitoring.In this paper,a three-dimensional finite-element model is first established for a highway bridge over a railroad on No.312 National Highway.Based on design drawings,the dynamic characteristics of the bridge are studied using finite element analysis and ambient vibration measurements.Thus,a set of data is selected based on sensitivity analysis and optimization theory;the finite element model of the bridge is updated.The numerical and experimental results show that the updated method is more simple and effective,the updated finite element model can reflect the dynamic characteristics of the bridge better,and it can be used to predict the dynamic response under complex external forces.It is also helpful for further damage identification and health condition monitoring.

  6. Flutter Derivatives Identification and Aerodynamic Performance of an Optimized Multibox Bridge Deck

    Directory of Open Access Journals (Sweden)

    Zhida Wang

    2016-01-01

    Full Text Available The bridge deck sections used for long-span suspension bridges have evolved through the years, from the compact box deck girders geometrical configurations to twin-box and three-box bridge decks sections. The latest generation of split and multiple-box bridge decks proved to have better aerodynamic behavior; thus further optimization methods are sought for such geometrical configurations. A new type of multibox bridge deck, consisting of four aerodynamically shaped deck boxes, two side decks for the traffic lanes and two middle decks for the railway traffic, connected between them by stabilizing beams, was tested in the wind tunnel for identifying the flutter derivatives and to verify the aerodynamic performance of the proposed multibox deck. Aerodynamic static force coefficients were measured for the multibox bridge deck model, scaled 1 : 80, for Reynolds numbers up to 5.1 × 105, under angles of attack between −8° and 8°. Iterative Least Squares (ILS method was employed for identifying the flutter derivatives of the multibox bridge deck model, based on the results obtained from the free vibration tests and based on the frequency analysis the critical flutter wind speed for the corresponding prototype of the multibox bridge was estimated at 188 m/s.

  7. Numerical and Experimental Study of Free Vibration Characteristics of a Cable-Stayed Bridge

    Institute of Scientific and Technical Information of China (English)

    Zi Jianmin; Wang Yuanhan; Zhu Hongping

    2006-01-01

    The main aim of this study is to understand the dynamic behavior of a cable-stayed bridge,using both numerical and experimental analysis. A three-dimensionai finite element model for the bridge was developed for the free vibration analysis and the ambient vibration properties of the bridge were determined through field testing. The experimental and numerical results of natural frequencies and the associated mode shapes were compared, and the high accuracy between them shows that the 3D model is capable of approximately representing the dynamic behavior of the bridge and the use of ambient vibration survives in future testing of the bridge. These dynamic characteristics can be used as the basis for updating the finite element model and also for global damage detection.

  8. To the question of reliability and durability ballastless deck of bridge

    Directory of Open Access Journals (Sweden)

    V.V. Prystynskaya

    2012-12-01

    Full Text Available The principal causes of operational defects in bridge ballastless deck plates are considered in the article. The drawbacks of these plates construction that prevent from achieving a higher level of bridge framework reliability and durability have been analysed.

  9. Deformation and failure of the ice bridge on the Wilkins Ice Shelf, Antarctica

    NARCIS (Netherlands)

    Humbert, A.; Gross, D.; Müller, R.; Braun, M.; van de Wal, R.S.W.; van den Broeke, M.R.; Vaughan, D.G.; van de Berg, W.J.

    2010-01-01

    A narrow bridge of floating ice that connected the Wilkins Ice Shelf, Antarctica, to two confining islands eventually collapsed in early April 2009. In the month preceding the collapse, we observed deformation of the ice bridge by means of satellite imagery and from an in situ GPS station. TerraSAR-

  10. Identification and Level 1 Damage Detection of the Z24 Highway Bridge by Frequency Domain Decomposition

    DEFF Research Database (Denmark)

    Brincker, Rune; Andersen, P.; Cantieni, R.

    2001-01-01

    A series of 15 progressive damage tests were performed on a prestressed concrete highway bridge in Switzerland. The ambient response of the bridge was recorded for each damage case with a relatively large number of sensors. Changes in frequencies, damping ratios and MAC values were determined. An...

  11. Designing of support zones of concrete bridges to withstand action of static and dynamic load

    Directory of Open Access Journals (Sweden)

    Gligorijević Milan

    2010-01-01

    Full Text Available In the paper are presented some of the acquired experiences in designing and construction of bridge structures in several countries, with a special attention to the analysis of support zones and expansion joints behavior of a number of road bridges. During destruction or damage of bridges, there is a small probability, but still there, that the human lives might be endangered (Kobe, Japan 17th January 1995; what is likely, however, is that it will be very difficult to help the injured in the region. Considering that the characteristics of removal of supports has a great influence on the behavior of the entire bridge structure, the design of support joints and connections must be paid due attention. In the recent decades, efforts are made to enhance research of all engineering structure, and thus the bridge structures and their weak points.

  12. Combined Differential and Static Pressure Sensor based on a Double-Bridged Structure

    DEFF Research Database (Denmark)

    Pedersen, Casper; Jespersen, S.T.; Krog, J.P.;

    2005-01-01

    A combined differential and static silicon microelectromechanical system pressure sensor based on a double piezoresistive Wheatstone bridge structure is presented. The developed sensor has a conventional (inner) bridge on a micromachined diaphragm and a secondary (outer) bridge on the chip...... substrate. A novel approach is demonstrated with a combined measurement of outputs from the two bridges, which results in a combined deduction of both differential and static media pressure. Also following this new approach, a significant improvement in differential pressure sensor accuracy is achieved....... Output from the two bridges depends linearly on both differential and absolute (relative to atmospheric pressure) media pressure. Furthermore, the sensor stress distributions involved are studied by three-dimensional finite-element (FE) stress analysis. Furthermore, the FE analysis evaluates current...

  13. The "Why" and "Where" of the Tappan Zee Bridge: A Lesson in Site Location, Physical Geography, and Politics

    Science.gov (United States)

    Mitchell, Jerry T.; Cantrill, Jeremy; Kearse, Justin

    2012-01-01

    Bridges are some of the most majestic features in the American landscape. For classrooms, the bridge serves as an important component of one of the main themes of geography: movement. One bridge, north of Manhattan and crossing the Hudson River, is the Tappan Zee. One aspect that stands out in a way that does not at all appear reasonable: the…

  14. 冲击荷载下大型箱涵输水安全性的数值分析%Numerical analysis for safety of water transmission of large-scale box culvert under blasting load

    Institute of Scientific and Technical Information of China (English)

    崔溦; 宋慧芳; 张社荣

    2012-01-01

    Safety of water transmission of large-scale box culvert subjected to blast loading is an important topic in civil engineering, study on it involves several factors, such as, propagation of shock wave, interaction between foundation and structure, and so on. A numerical analysis technology was used to simulate the response of a large-scale box culvert under blasting load. Interaction between soil and box culvert was taken into account with a contact model. Arbitrary Lagrangian Eulerian ( ALE) method was used to describe water, and penalty method was employed to simulate fluid-structure interaction. The results showed that under condition of water transmission, ALE description technology can describe the effect of blasting in soil on structure; water can transfer loads to the middle wall of box culvert and mitigate the effect of shock load on the side wall, then improve the whole security of structure; among all the conditions of water transmission, the effect of pressure flow on safety of structure is most obvious.%冲击荷载对大型箱涵输水安全的影响是工程界关注的重要问题,其研究涉及到冲击荷载传播、土—结构物—水相互作用等诸多方面.采用数值分析技术,土与箱涵之间设置接触面单元,水体采用任意拉格朗日欧拉法描述,采用罚方法模拟水与箱涵相互作用,研究了爆炸冲击荷载对大型箱涵输水安全性的影响.研究结果表明:ALE法可以较好揭示土中爆破对输水情况下钢筋混凝土结构物的影响;输水情况下水体能传递荷载到箱涵中墙上,并缓冲冲击荷载对边墙的过大影响,可改善结构整体安全性;有压输水情况对结构物安全影响最为明显.

  15. Ship-bridge collision force mechanism and composite anti-collision system%船桥碰撞力理论分析及复合材料防撞系统

    Institute of Scientific and Technical Information of China (English)

    刘伟庆; 方海; 祝露; 韩娟; 吴志敏

    2013-01-01

    考虑桥墩刚度与船艏刚度,采用质点弹簧模型,建立了船桥碰撞动力方程,分析了桥墩与船艏的相对刚度、碰撞接触时间对峰值撞击力的影响规律,修正了我国《公路桥涵设计通用规范》中漂浮物撞击力公式。研制了新型纤维增强复合材料防撞系统,开展了冲击性能试验,实现了相关桥梁防船撞工程应用。结果表明:当桥船相对刚度之比小于50时,峰值撞击力随桥船相对刚度的增大呈对数形式增大;当桥船相对刚度之比大于等于50时,峰值撞击力可近似按欧洲统一规范取值。碰撞接触时间与船舶质量、船艏刚度相关。复合材料防撞系统能有效延长船桥碰撞接触时间,大幅削减撞击力,从而有效保护桥墩结构安全,减轻船舶受损程度,具有显著的技术经济优势。%The governing equation of ship-bridge collision, considering the influence of pier stiffness and ship stiffness, was proposed by using the mass-spring model.The effects of bridge-ship relative stiffness and contact time on the peak impact force were analyzed.The impact force formula of flot-sam in the General Code for Design of Highway Bridges and Culverts was revised.Meanwhile, an innovative fiber reinforced composite anti-collision system was developed.The corresponding impact tests were conducted.Furthermore, this composite anti-collision system is applied in the practical bridge anti-collision engineering.The results show that when the bridge-ship relative stiffness is less than 50 , the peak impact force logarithmically increases to the increase in the bridge-ship relative stiffness;otherwise, the peak impact force can be approximately calculated according to European Standard.The contact time is related to the mass and stiffness of ship.The composite anti-collision system can effectively prolong the contact time of ship-bridge collision and decrease the impact force substantially;therefore the

  16. Theoretical and experimental study on shear lag effect of partially cable-stayed bridge

    Institute of Scientific and Technical Information of China (English)

    WU Gao-feng; XU Hong

    2005-01-01

    In order to resolve the traffic congestion problem, many cable-stayed bridges are designed with a large width to span ratio. This results in significant shear lag effect to cause nonuniform stress distribution along the flanges of the beam of bridge.This paper reports study on the shear lag effect of the Lanzhou Xiaoxihu Yellow River Bridge. A 3D finite element model of the bridge was developed and finite element analysis (FEA) was done to obtain the theoretical results. To evaluate the theoretical results, a scaled model was made to conduct static test in laboratory. The experiment results accorded with the results obtained by FEA. It is proved that FEA is an effective method to predict shear lag effect of bridges of this type.

  17. New bridge circuit-type detector to measure precise resistance change of strain gauge at low temperature and magnetic field

    OpenAIRE

    Ohashi, Masashi; Kishii, Nobuya; Tateno, Shota

    2016-01-01

    We report a new highly accurate and versatile bridge-circuit-type detector that has a simple structure and demonstrates a low degree of error for measurements of thermal expansion and magnetostriction by the strain gauge method. As an example, a commercial physical property measurement system (PPMS) is combined with a compact bridge-circuit box. Thermal expansion and magnetostriction are calculated from the resistance of the bridge and bridge voltage, measured by the operation of a standard P...

  18. 76 FR 72957 - 4th Annual Trauma Spectrum Conference: Bridging the Gap Between Research and Clinical Practice of...

    Science.gov (United States)

    2011-11-28

    ... HUMAN SERVICES National Institutes of Health 4th Annual Trauma Spectrum Conference: Bridging the Gap... Annual Trauma Spectrum Conference: Bridging the Gap Between Research and Clinical Practice of... conference information, visit the Trauma Spectrum Conference Web site at...

  19. Dynamic analysis of soil-steel composite bridges for high speed railway traffic : Case study of a bridge in Märsta, using field measurements and FE-analysis

    OpenAIRE

    Mellat, Peyman

    2012-01-01

    Soil-steel composite bridge refers to structures where a buried flexible corrugated steel pipe works in composite action with the surrounding soil. These structures are being increasingly used in road and railway projects as an alternative to standard type bridges, e.g. short- and medium span concrete beam- and portal frame bridges. On account of their economic advantage and short and easy construction operation, soil-steel composite bridges are getting more popular as railway crossings locat...

  20. Nuwe Woordeboek sonder Grense: A Typological and Communicative Bridge

    Directory of Open Access Journals (Sweden)

    Mariza Steyn

    2011-10-01

    Full Text Available

    ABSTRACT: Within the South African lexicographical context, there have been several pleas for Afrikaans learner's and school dictionaries that incorporate innovative strategies and provide for specific identified target users and their particular problems. Nuwe Woordeboek sonder Grense (NWSG is an Afrikaans learner's dictionary that is aimed at a specific group of users, can be used for text reception and text production and forms part of an established textbook series. Through new strategies and adaptations, this dictionary tries to form a bridge between different typological categories and to be a functional instrument for use in the classroom. In accordance with the theo-retical formulation of dictionary functions, NWSG tries to further communication through initial support in and eventual assimilation of the foreign language. In this article, theoretical insights regarding learner's dictionaries as well as practical examples from NSWG are combined to illus-trate the possibilities of a more user-friendly product.

    Keywords: LEARNER'S DICTIONARY, USERS, TYPOLOGY, BRIDGE LANGUAGE, TEXT RECEPTION, MACROSTRUCTURE, TEXT PRODUCTION, MICRO-ARCHITECTURE, FRAME STRUCTURE

    *****

    OPSOMMING: Nuwe Woordeboek sonder Grense: 'n Tipologiese en kommu-nikatiewe brug. Binne die Suid-Afrikaanse leksikografiese konteks is daar reeds verskeie pleidooie gerig vir Afrikaanse aanleerder- en skoolwoordeboeke wat vernuwende strategieë inkor-poreer en vir spesifieke, geïdentifiseerde teikengebruikers en hul eiesoortige probleme voorsiening maak. Nuwe Woordeboek sonder Grense (NWSG is 'n Afrikaanse aanleerderwoordeboek wat op 'n spesifieke groep leerders gerig is, vir teksresepsie en teksproduksie gebruik kan word en deel van 'n gevestigde handboekreeks uitmaak. Dié woordeboek probeer om deur nuwe strategieë en aan-passings 'n brug te vorm tussen verskillende tipologiese kategorieë en 'n funksionele gebruiks-instrument in die klaskamer te wees. In

  1. Development and simulation of microfluidic Wheatstone bridge for high-precision sensor

    Science.gov (United States)

    Shipulya, N. D.; Konakov, S. A.; VKrzhizhanovskaya, V.

    2016-08-01

    In this work we present the results of analytical modeling and 3D computer simulation of microfluidic Wheatstone bridge, which is used for high-accuracy measurements and precision instruments. We propose and simulate a new method of a bridge balancing process by changing the microchannel geometry. This process is based on the “etching in microchannel” technology we developed earlier (doi:10.1088/1742-6596/681/1/012035). Our method ensures a precise control of the flow rate and flow direction in the bridge microchannel. The advantage of our approach is the ability to work without any control valves and other active electronic systems, which are usually used for bridge balancing. The geometrical configuration of microchannels was selected based on the analytical estimations. A detailed 3D numerical model was based on Navier-Stokes equations for a laminar fluid flow at low Reynolds numbers. We investigated the behavior of the Wheatstone bridge under different process conditions; found a relation between the channel resistance and flow rate through the bridge; and calculated the pressure drop across the system under different total flow rates and viscosities. Finally, we describe a high-precision microfluidic pressure sensor that employs the Wheatstone bridge and discuss other applications in complex precision microfluidic systems.

  2. Aerodynamics of bridge hangers in smooth and turbulent flow and implications on aeroelastic stability

    DEFF Research Database (Denmark)

    Demartino, Cristoforo; Ricciardelli, Francesco; Georgakis, Christos T.

    2015-01-01

    The aerodynamics of circular cylinders featuring geometric imperfections, such as bridge cables, has received much attention in recent years due to the recognition that such imperfections can be the cause of large amplitude vibrations. Bridge cables are usually made of strands or wires protected...... by an extruded High Density PolyEthylene (HDPE) circular sheath [1]. In the last 20 years, several bridge cable manufacturers have introduced surface modifications on HDPE sheath in order to reduce the drag and to ensure the aerodynamic stability in all climatic conditions. In the case of plain HDPE sheaths......, of mechanical damage occurring during transport and installation, as well as of the ageing process due to the exposure to environmental factors. Few experimental works are already available dealing with the effects of imperfections on the aerodynamics of bridge cables. For example, Matteoni and Georgakis...

  3. Inspection and Numerical Analysis of an Ottoman Railway Bridge in Jordan

    Directory of Open Access Journals (Sweden)

    Amin H. Almasri

    2016-01-01

    Full Text Available The construction of bridges represents a big challenge, since they require enormous economic effort and specialized technical skills. Bridges were historically important as they help connecting people and thus diffusing cultures, sharing ideas, and providing the backbone of transportation networks. This study focuses on the inspection and structural analysis of a 20th-century Ottoman railway stone arched bridge located on the Hejaz railway network in Jordan. The bridge has a very important cultural heritage value which stems from its history. The bridge stone material was cut and tested to determine its strength, in order to be used in the analysis. The structural analysis was carried out to assess the structural condition of the bridge and its suitability for reuse. The study includes static analysis under gravity loads and seismic analysis under earthquake loads. Despite the existence of deterioration in the bridge body construction materials due to a combination of human and natural factors, the analysis results proved enough structural capability to sustain the imposed gravity loads, but not a strong earthquake.

  4. Dynamic characterization and damage detection in the I-40 bridge over the Rio Grande

    Energy Technology Data Exchange (ETDEWEB)

    Farrar, C.R.; Baker, W.E.; Bell, T.M.; Cone, K.M.; Darling, T.W.; Duffey, T.A.; Eklund, A.; Migliori, A.

    1994-06-01

    In the 1960`s and 1970`s over 2500 bridges were built in the U.S. with a design similar to those on Interstate 40 over the Rio Grande in Albuquerque, New Mexico. These bridges were built without structural redundancy and typically have only two plate girders carrying the entire dead and live loads. Failure of either girder is assumed to produce catastrophic failure of the bridge, hence these bridges are referred to as fracture-critical bridges. The Federal Highway Administration (FHWA) and the National Science Foundation (NSF) have provided funds to New Mexico State University (NMSU) through the New Mexico State Highway and Transportation Department (NMSH&TD) and The Alliance For Transportation Research (ATR) for evaluation and testing of the existing fracture critical bridges over the Rio Grande. Because the 1-40 bridges over the Rio Grande were to be razed during the summer of 1993, the investigators were able to introduce simulated fatigue cracks, similar to those observed in the field, into the structure in order to test various damage identification methods and to observe the changes in load paths through the structure caused by the cracking. To support this research effort, NMSU contracted Los Alamos National Laboratory (LANL) to perform experimental modal analyses, and to develop experimentally verified numerical models of the bridge. Scientists from the LANL`s Condensed Matter and Thermal Physics Group (P-10) applied state-of-the-art sensors and data acquisition software to the modal tests. Engineers from the LANL`s Advanced Engineering Technology Group (MEE-13) conducted ambient and forced vibration tests to verify detailed and simplified finite element models of the bridge. Forced vibration testing was done in conjunction with engineers from Sandia National Laboratory (SNL) who provided and operated a hydraulic shaker.

  5. Bridge over troubled gas: clusters and associations under the SMC and LMC tidal stresses

    CERN Document Server

    Bica, E; Bonatto, C; Garcia-Dias, R; Kerber, L; Dias, B; Barbuy, B; Balbinot, E

    2015-01-01

    We obtained SOAR telescope B and V photometry of 14 star clusters and 2 associations in the Bridge tidal structure connecting the LMC and SMC. These objects are used to study the formation and evolution of star clusters and associations under tidal stresses from the Clouds. Typical star clusters in the Bridge are not richly populated and have in general relatively large diameters (~30-35 pc), being larger than Galactic counterparts of similar age. Ages and other fundamental parameters are determined with field-star decontaminated photometry. A self-consistent approach is used to derive parameters for the most-populated sample cluster NGC 796 and two young CMD templates built with the remaining Bridge clusters. We find that the clusters are not coeval in the Bridge. They range from approximately a few Myr (still related to optical HII regions and WISE and Spitzer dust emission measurements) to about 100-200 Myr. The derived distance moduli for the Bridge objects suggests that the Bridge is a structure connecti...

  6. Decision support system for integrating remote sensing in bridge condition assessment and preservation

    Science.gov (United States)

    Endsley, Arthur; Brooks, Colin; Harris, Devin; Ahlborn, Tess; Vaghefi, Khatereh

    2012-04-01

    Since the National Bridge Inventory (NBI) was first conducted, structural health monitoring (SHM) of U.S. bridge infrastructure has consisted largely of time and labor-intensive surveys with subjective results. In-situ and embedded sensors, while more reliable and accurate, can be costly and in many cases infeasible for SHM because they require installation in hard-to-reach places or during construction. Remote sensing (RS) technologies such as radar, electrooptical imaging and laser scanning may offer an innovative, cost-effective method of monitoring the dynamic conditions of U.S. bridges in real-time. While some RS techniques may be costly for state agencies to deploy on their own, RS imagery is available through government agencies or commercial vendors for moderate or no cost. How can disparate RS datasets be integrated with one another and with inventory data in a way that is meaningful to bridge asset management decision makers? This paper discusses the development and functionality of the Bridge Condition Decision Support System (DSS), a web-based asset management tool for bridge managers and inspectors. The DSS seamlessly merges bridge metrics from RS data with NBI inventory data allowing decision makers to compare up-to-date bridge condition metrics from multiple inputs as a time series. It enables analysis of RS and inventory data available through user-friendly web services which can also expose virtually unlimited server-side data processing. Using open-source software, the authors developed a scalable, spatially-aware bridge condition database with a fast and flexible server application programming interface (API) and a cross-browser compatible web mapping application written in Javascript.

  7. Bridge between public perception and expert assessment of nuclear safety

    International Nuclear Information System (INIS)

    Preparation of the brief consisted of a comprehensive review of literature, selective interviews of available representative parties, and categorization of the spectrum of opinions. Analysis of the information thus obtained included identification of reconcilable and irreconcilable differences among the opinions and indication of possible ways to bridge some of the differences. Opinions were generally found to be best categorized as the pro, neutral, and contra opinions associated with experts and the public. The primary issues separating the opposing groups appear to be the following: 1) the required input for probabilistic risk analysis of accidents; 2) the evaluation of what constitutes an acceptable risk; 3) the evaluation of potential long-term consequences; 4) the general need for nuclear energy; and 5) the long-term risk to public health. Among the above issues, potential for reconciliation was found only for the first two, while the latter issues, because of the relatively short history of the industry and paucity of knowledge on relevant factors, were found difficult to reconcile without expansion of our present knowledge and data base. Reconciliation, generally, was proposed through augmentation of communication among the opposing groups through the availability of appropriate fora and development of a general spirit of good intention for a common cause: mankind's ultimate well-being

  8. Matters of taste: bridging molecular physiology and the humanities.

    Science.gov (United States)

    Rangachari, P K; Rangachari, Usha

    2015-12-01

    Taste perception was the focus of an undergraduate course in the health sciences that bridged the sciences and humanities. A problem-based learning approach was used to study the biological issues, whereas the cultural transmutations of these molecular mechanisms were explored using a variety of resources (novels, cookbooks, and films). Multiple evaluation procedures were used: problem summaries and problem-solving exercises (tripartite problem-solving exercise) for the problem-based learning component and group tasks and individual exercises for the cultural issues. Self-selected groups chose specific tasks from a prescribed list of options (setting up a journal in molecular gastronomy, developing an electronic tongue, designing a restaurant for synesthetes, organizing a farmers' market, marketing a culinary tour, framing hedonic scales, exploring changing tastes through works of art or recipe books, and crafting beers for space travel). Individual tasks were selected from a menu of options (book reviews, film reviews, conversations, creative writing, and oral exams). A few guest lecturers (wine making, cultural anthropology, film analysis, and nutritional epidemiology) added more flavor. The course was rated highly for its learning value (8.5 ± 1.2, n = 62) and helped students relate biological mechanisms to cultural issues (9.0 ± 0.9, n = 62). PMID:26628651

  9. Influence of central buckle on suspension bridge dynamic characteristics and driving comfort

    Institute of Scientific and Technical Information of China (English)

    王达; 邓扬; 刘扬

    2015-01-01

    The central buckle, which is often used in a suspension bridge, can improve bridges’ performance in the actual operation condition. The influence of the central buckle on natural vibration characteristics and bridge-deck driving comfort of a long-span suspension bridge is studied by using a case study of Siduhe Suspension Bridge in China. Based on the finite element software ANSYS and independently complied program, the influence of the central buckle on the structure force-applied characteristics of a long-span suspension bridge has been explored. The results show that the huge increases of natural frequencies can result in the presence of central buckles because of the increases of bending and torsional rigidities. The central buckle basically makes the stiffening girders and cables within the triangular area covered as a relatively approximate rigid area. Hence, the central buckle can reduce the torsional displacement of the main girder. However, the increases of bending and torsional rigidities have little influence on the impact factor, which is obtained by using vehicle-bridge coupled vibration analysis. This means that the central buckle has little effect on the comfort indices. In addition, it is found that the central buckle can enhance the bridge deck’s driving stability due to the decrease of the torsional displacements of the main girder.

  10. Tests and assessments of NDT methods for concrete bridges

    Science.gov (United States)

    Krieger, Juergen; Krause, M.; Wiggenhauser, Herbert

    1998-03-01

    A research project is described involving a comparison of different non-destructive test methods for concrete bridges. A cooperative test series was started with the aim to compare and evaluate the performance and benefits of the latest technical developments in this field. For this purpose test specimens with localized defects were produced. Different modifications of radar, ultrasonic-echo and impact-echo methods were investigated. Including two- and three- dimensional reconstruction models. The experiments were accompanied by numerical simulation of the propagation of sound waves and microwaves. The results showed that the radar and the ultrasonic methods were efficient tools to locate the tendon ducts accurately if the reinforcing bars were not to narrowly spaced. The ultrasonic imaging methods were capable of identifying injection and compaction faults in a blind test. The good performance of the impact-echo method with regard to locating tendon ducts which was claimed in several publications could not be validated in the present investigations. The simulation models provided valuable information on how to improve the experimental test program and its evaluation.

  11. Science communication: Bridging the gap between theory and practise

    CERN Multimedia

    2001-01-01

    The 6th Public Communication of Science and Technology network conference will be held at CERN on 1-3 Febraury 2001. Scientists and communication professionals will analyse the state of the art of science communication and the new perception people have about science in the media from newspapers to the Web.   Will communication be able to bridge the gap between Science and Society? What is the impact of science communication on the public? How do novel means of communications change the perception of science for the general public? These and other interesting questions will be addressed at the 6th Public Communication of Science and Technology Meeting, to be held at CERN on 1-3 February 2001. More than 250 people from all over the world are expected to attend the conference which will be an important meeting place for communication professionals covering the social, political, technical and cultural aspects of science and technology communication. Georges Boixader after Gary Larsson. The conferenc...

  12. Advanced bridge (interferometric) phase and amplitude noise measurements

    CERN Document Server

    Rubiola, E; Rubiola, Enrico; Giordano, Vincent

    2005-01-01

    The measurement of the close-to-the-carrier noise of rf and microwave devices is a relevant issue in time and frequency metrology and in some fields of electronics, physics and optics. While phase noise is the main concern, amplitude noise is often of interest. The highest sensitivity is achieved with the bridge (interferometric) method, which consists of the amplification and synchronous detection of the noise sidebands after suppressing the carrier by vector subtraction of an equal signal. A substantial progress in understanding the flicker noise mechanism of the interferometer results in new schemes that improve by 20--30 dB the sensitivity at low Fourier frequencies. The article provides the complete theory and detailed design criteria, and reports on the implementation of a prototype. In real-time measurements, a background noise of -175 -180 dBrad^2/Hz has been obtained at f=1 Hz off the 100 MHz carrier. Exploiting correlation and averaging in similar conditions, the sensitivity exceeds -185 dBrad^2/Hz ...

  13. Concrete bridge prioritization system

    OpenAIRE

    Kesselring, Debbie Anne

    1995-01-01

    An alternative method of prioritization for concrete bridge maintenance, repair, and rehabilitation activities is required due to the inability of the current system to manage the increasing nmnber of aging concrete bridges. The Concrete Bridge Prioritization System was proposed because of its ability to address the critical technical parameters of safety and cost benefit in prioritization of funding and work allocation. The analysis includes four parts, service life assessment, s...

  14. Soft-switching PWM full-bridge converters topologies, control, and design

    CERN Document Server

    Ruan, Xinbo

    2014-01-01

    Soft-switching PWM full-bridge converters have been widely used in medium-to-high power dc-dc conversions for topological simplicity, easy control and high efficiency. Early works on soft-switching PWM full-bridge converter by many researchers included various topologies and modulation strategies.  However, these works were scattered, and the relationship among these topologies and modulation strategies had not been revealed. This book intends to describe systematically the soft-switching techniques for pulse-width modulation (PWM) full-bridge converters, including the topologies, control and

  15. Psychoanalysis, a bridge between attachment research and neurobiology.

    Science.gov (United States)

    Rendon, Mario

    2008-06-01

    Attachment theory and neurobiology are at the forefront of scientific research, particularly in the area of child psychiatry. Several authors have encountered a surprising isomorphism between findings in these areas and concepts central in psychoanalysis. The author postulates that attachment theory is an outcome of the history of the transformation of the old concept of libido now applied interpersonally. The author also postulates that the neurobiology of attachment mediates but does not substitute psychoanalysis for the final understanding of the human bond. Findings in both fields, attachment theory and psychobiology, often compellingly lead to psychoanalytic concepts; on the other hand, the neurobiology of the psyche does not make full sense without the wealth of research conducted by psychoanalysts during the 20th century. The concept of seduction in particular, in its broad sense, is akin to mirroring and attachment and a useful tool in this regard. Although some cling to the idea of the purity of psychoanalysis and see these kin areas as a threat to its integrity, the author believes that psychoanalysis, serving as a bridge between them, can only be enriched by their empirical and experimental outcomes. The American Journal of Psychoanalysis (2008) 68, 148-155. doi:10.1057/ajp.2008.4.

  16. Building Carbon Bridges on and between Fullerenes in Helium Nanodroplets.

    Science.gov (United States)

    Krasnokutski, Serge A; Kuhn, Martin; Kaiser, Alexander; Mauracher, Andreas; Renzler, Michael; Bohme, Diethard K; Scheier, Paul

    2016-04-21

    We report the observation of sequential encounters of fullerenes with C atoms in an extremely cold environment. Experiments were performed with helium droplets at 0.37 K doped with C60 molecules and C atoms derived from a novel, pure source of C atoms. Very high-resolution mass spectra revealed the formation of carbenes of the type C60(C:)n with n up to 6. Bridge-type bonding of the C adatoms to form the known dumbbell C60═C═C60 also was observed. Density functional theory calculations were performed that elucidated the carbene character of the C60(C:)n species and their structures. Mass spectra taken in the presence of water impurities and in separate experiments with added H2 also revealed the formation of the adducts C60Cn(H2O)n and C60Cn(H2)n probably by H-OH and H-H bond insertion, respectively, and nonreactivity for the dumbell. So C adatoms that form carbenes C60(C:)n can endow pristine C60 with a higher chemical reactivity. PMID:27043313

  17. Building Carbon Bridges on and between Fullerenes in Helium Nanodroplets

    Science.gov (United States)

    2016-01-01

    We report the observation of sequential encounters of fullerenes with C atoms in an extremely cold environment. Experiments were performed with helium droplets at 0.37 K doped with C60 molecules and C atoms derived from a novel, pure source of C atoms. Very high-resolution mass spectra revealed the formation of carbenes of the type C60(C:)n with n up to 6. Bridge-type bonding of the C adatoms to form the known dumbbell C60=C=C60 also was observed. Density functional theory calculations were performed that elucidated the carbene character of the C60(C:)n species and their structures. Mass spectra taken in the presence of water impurities and in separate experiments with added H2 also revealed the formation of the adducts C60Cn(H2O)n and C60Cn(H2)n probably by H–OH and H–H bond insertion, respectively, and nonreactivity for the dumbell. So C adatoms that form carbenes C60(C:)n can endow pristine C60 with a higher chemical reactivity. PMID:27043313

  18. Bridging the gap between health care professionals and communities

    Directory of Open Access Journals (Sweden)

    Sally Hartley

    2004-10-01

    Full Text Available Introduction Bridging the gap between health care professionals and communities is a difficult task. It involves establishing a culture of community participation and improving the process of communication between the two groups. Effective communication between these groups is not easy. The people concerned often speak different languages, have different levels of education and competence, different priorities in life and generally understand things differently. In addition, the greatest proportion of communication is transmitted non-verbally, through gestures, facial expressions and ‘body language’. This is important for two reasons. Firstly, any feelings of pity, superiority, frustration, dismissal or respect, will almost certainly be transmitted through these alternative modes of communication, they carry much more powerful messages than those contained in what is said. Secondly, many of these non-verbal messages, with the major exception of speech intonation, are visual and are therefore missed by people who cannot see well enough to pick them up. This combines to give an effective recipe for communication breakdown.

  19. Self-assembly of bridged silsesquioxanes: modulating structural evolution via cooperative covalent and noncovalent interactions.

    Science.gov (United States)

    Creff, Gaelle; Pichon, Benoît P; Blanc, Christophe; Maurin, David; Sauvajol, Jean-Louis; Carcel, Carole; Moreau, Joël J E; Roy, Pascale; Bartlett, John R; Man, Michel Wong Chi; Bantignies, Jean-Louis

    2013-05-01

    The self-assembly of a bis-urea phenylene-bridged silsesquioxane precursor during sol-gel synthesis has been investigated by in situ infrared spectroscopy, optical microscopy, and light scattering. In particular, the evolution of the system as a function of processing time was correlated with covalent interactions associated with increasing polycondensation and noncovalent interactions such as hydrogen bonding. A comprehensive mechanism based on the hydrolysis of the phenylene-bridged organosilane precursor prior to the crystallization of the corresponding bridged silsesquioxane via H-bonding and subsequent irreversible polycondensation is proposed. PMID:23574041

  20. Solvent-Exposed Salt Bridges Influence the Kinetics of alpha-Helix Folding and Unfolding

    OpenAIRE

    Meuzelaar, Heleen; Tros, Martijn; Huerta-Viga, Adriana; Chris N. van Dijk; Vreede, Jocelyne; Woutersen, Sander

    2014-01-01

    Salt bridges are known to play an essential role in the thermodynamic stability of the folded conformation of many proteins, but their influence on the kinetics of folding remains largely unknown. Here, we investigate the effect of Glu-Arg salt bridges on the kinetics of α-helix folding using temperature-jump transient-infrared spectroscopy and steady-state UV circular dichroism. We find that geometrically optimized salt bridges (Glu– and Arg+ are spaced four peptide units apart, and the Glu/...

  1. Long span cable supported bridges - present technology and trends

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1998-01-01

    The activity within the field of long-span cable supported bridges has never been larger than at the end of the 20th century. The technology is well advanced to cope with the present challenges but it is also approaching its limits so if the trend towards ever increasing spans continues into the ......The activity within the field of long-span cable supported bridges has never been larger than at the end of the 20th century. The technology is well advanced to cope with the present challenges but it is also approaching its limits so if the trend towards ever increasing spans continues...

  2. Sub-Nyquist Sampling: Bridging Theory and Practice

    CERN Document Server

    Mishali, Moshe

    2011-01-01

    Sampling theory encompasses all aspects related to the conversion of continuous-time signals to discrete streams of numbers. The famous Shannon-Nyquist theorem has become a landmark in the development of digital signal processing. In modern applications, an increasingly number of functions is being pushed forward to sophisticated software algorithms, leaving only those delicate finely-tuned tasks for the circuit level. In this paper, we review sampling strategies which target reduction of the ADC rate below Nyquist. Our survey covers classic works from the early 50's of the previous century through recent publications from the past several years. The prime focus is bridging theory and practice, that is to pinpoint the potential of sub-Nyquist strategies to emerge from the math to the hardware. In that spirit, we integrate contemporary theoretical viewpoints, which study signal modeling in a union of subspaces, together with a taste of practical aspects, namely how the avant-garde modalities boil down to concr...

  3. The literacy gaps bridge-building strategies for English language learners and standard English learners

    CERN Document Server

    Soto, Ivannia M

    2009-01-01

    Build bridges of support so English language learners and standard English learners can learn alongside their peers! This comprehensive, research-based guide helps teachers bridge multiple gaps and promote learning for English language learners (ELLs) and standard English learners (SELs). The authors provide strategies, examples, and tools to address: The gap between students and texts: covering word recognition, background knowledge, comprehension, and academic language development The gap between students and teachers: including sociocultural differences between teachers and students and tea

  4. Research and application of non-clay low damage temporary bridging drilling/completion fluids system

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Following the basic theory of protecting gas-reservoirs from damage with the temporary bridging technology,inert calcium carbonate (CaCO3) particles,whose diameter is consistent with the size of pores or apertures in the reservoir,were selected as the bridging agent,and modified resolvable starch was selected as filtration loss reducing particles to form the non-clay low damage temporary bridging drilling/completion fluids system (NLTDFS). Under the simulated condition of the well bottom during real drillin...

  5. Modal Identification and Damage Detection on a Concrete Highway Bridge by Frequency Domain Decomposition

    DEFF Research Database (Denmark)

    Brincker, Rune; Andersen, Palle; Zhang, Lingmi

    2007-01-01

    As a part of a research project co-founded by the European Community, a series of 15 damage tests were performed on a prestressed concrete highway bridge in Switzerland. The ambient response of the bridge was recorded for each damage case. A dense array of instruments allowed the identification...... is to show the application of the FDD method as an efficient way to perform health monitoring of civil engineering structures. The modal properties, frequencies, damping ratios and mode shapes for the different damage cases were compared with those for the undamaged bridge....

  6. An evaluation of iced bridge hanger vibrations through wind tunnel testing and quasi-steady theory

    DEFF Research Database (Denmark)

    Gjelstrup, Henrik; Georgakis, Christos T.; Larsen, A.

    2012-01-01

    Bridge hanger vibrations have been reported under icy conditions. In this paper, the results from a series of static and dynamic wind tunnel tests on a circular cylinder representing a bridge hanger with simulated thin ice accretions are presented. The experiments focus on ice accretions produced...... roughness is also examined. The static force coefficients are used to predict parameter regions where aerodynamic instability of the iced bridge hanger might be expected to occur, through use of an adapted theoretical 3- DOF quasi-steady galloping instability model, which accounts for sectional axial......-indicating the possible inability of quasi-steady theory to fully predict these vibrational instabilities....

  7. Semiconductor bridge (SCB) detonator

    Science.gov (United States)

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

    1999-01-01

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

  8. Strengthening of a railway bridge with NSMR and CFRP tubes

    DEFF Research Database (Denmark)

    Täljsten, Björn; Bennitz, Anders; Danielsson, Georg

    2008-01-01

    Strengthening of structures with CFRP is today considered an accepted method to upgrade concrete structures. In this paper two different CFRP strengthening systems are combined to give extended service life to a Swedish double-trough-double-track railway bridge, constructed in concrete with a 10...

  9. Recent research and applications of numerical simulation for dynamic response of long-span bridges subjected to multiple loads.

    Science.gov (United States)

    Chen, Zhiwei; Chen, Bo

    2014-01-01

    Many long-span bridges have been built throughout the world in recent years but they are often subject to multiple types of dynamic loads, especially those located in wind-prone regions and carrying both trains and road vehicles. To ensure the safety and functionality of these bridges, dynamic responses of long-span bridges are often required for bridge assessment. Given that there are several limitations for the assessment based on field measurement of dynamic responses, a promising approach is based on numerical simulation technologies. This paper provides a detailed review of key issues involved in dynamic response analysis of long-span multiload bridges based on numerical simulation technologies, including dynamic interactions between running trains and bridge, between running road vehicles and bridge, and between wind and bridge, and in the wind-vehicle-bridge coupled system. Then a comprehensive review is conducted for engineering applications of newly developed numerical simulation technologies to safety assessment of long-span bridges, such as assessment of fatigue damage and assessment under extreme events. Finally, the existing problems and promising research efforts for the numerical simulation technologies and their applications to assessment of long-span multiload bridges are explored.

  10. Deterministic and Probabilistic Analysis of NPP Communication Bridge Resistance Due to Extreme Loads

    Directory of Open Access Journals (Sweden)

    Králik Juraj

    2014-12-01

    Full Text Available This paper presents the experiences from the deterministic and probability analysis of the reliability of communication bridge structure resistance due to extreme loads - wind and earthquake. On the example of the steel bridge between two NPP buildings is considered the efficiency of the bracing systems. The advantages and disadvantages of the deterministic and probabilistic analysis of the structure resistance are discussed. The advantages of the utilization the LHS method to analyze the safety and reliability of the structures is presented

  11. Bridging and Bonding Social Capital: which type is good for economic growth?

    OpenAIRE

    Beugelsdijk, Sjoerd; Smulders, Sjak

    2003-01-01

    In this paper we develop a model of growth and social capital, and test it using data from the European Value Survey (EVS). Following Putnam’s distinction between bonding and bridging social capital, we model social capital as participation in two types of social networks: first, closed networks of family and friends, and, second, open networks that bridge different communities. Agents have a preference for social interaction, which they trade off against material well-being. Participation in...

  12. Clinical and Radiological Evaluation after Arthroscopic Rotator Cuff Repair Using Suture Bridge Technique

    OpenAIRE

    Lee, Kwang Won; Seo, Dong Wook; Bae, Kyoung Wan; Choy, Won Sik

    2013-01-01

    Background We retrospectively assessed the clinical outcomes and investigated risk factors influencing retear after arthroscopic suture bridge repair technique for rotator cuff tear through clinical assessment and magnetic resonance arthrography (MRA). Methods Between January 2008 and April 2011, sixty-two cases of full-thickness rotator cuff tear were treated with arthroscopic suture bridge repair technique and follow-up MRA were performed. The mean age was 56.1 years, and mean follow-up per...

  13. Student assistantships: bridging the gap between student and doctor

    Directory of Open Access Journals (Sweden)

    Crossley JGM

    2015-06-01

    Full Text Available James GM Crossley,1,2 Pirashanthie Vivekananda-Schmidt1 1University of Sheffield School of Medicine, Sheffield, 2Chesterfield Royal Hospital NHS Foundation Trust, Chesterfield, UK Abstract: In 2009, the General Medical Council UK (GMC published its updated guidance on medical education for the UK medical schools – Tomorrow's Doctors 2009. The Council recommended that the UK medical schools introduce, for the first time, a clinical placement in which a senior medical student, “assisting a junior doctor and under supervision, undertakes most of the duties of an F1 doctor”. In the UK, an F1 doctor is a postgraduation year 1 (PGY1 doctor. This new kind of placement was called a student assistantship. The recommendation was considered necessary because conventional UK clinical placements rarely provided medical students with opportunities to take responsibility for patients – even under supervision. This is in spite of good evidence that higher levels of learning, and the acquisition of essential clinical and nontechnical skills, depend on students participating in health care delivery and gradually assuming responsibility under supervision. This review discusses the gap between student and doctor, and the impact of the student assistantship policy. Early evaluation indicates substantial variation in the clarity of purpose, setting, length, and scope of existing assistantships. In particular, few models are explicit on the most critical issue: exactly how the student participates in care and how supervision is deployed to optimize learning and patient safety. Surveys indicate that these issues are central to students' perceptions of the assistantship. They know when they have experienced real responsibility and when they have not. This lack of clarity and variation has limited the impact of student assistantships. We also consider other important approaches to bridging the gap between student and doctor. These include supporting the

  14. Study Based on Bridge Health Monitoring System on Multihazard Load Combinations of Earthquake and Truck Loads for Bridge Design in the Southeast Coastal Areas of China

    Directory of Open Access Journals (Sweden)

    Dezhang Sun

    2015-01-01

    Full Text Available Similar to American LRFD Bridge Design Specifications, the current Chinese bridge design code is fully calibrated against gravity load and live load. Earthquake load is generally considered alone and has its own methodology, however, which is not covered in the code in a consistent probability-based fashion. Earthquake load and truck load are the main loads considered in the basis of bridge design in more than 70% of seismic areas in China. They are random processes, and their combination is the main subject of this paper. Seismic characteristics of southeast coastal areas of China are discussed and an earthquake probability curve is calculated through seismic risk analysis. Using measured truck load data from a Bridge Health Monitoring System, the multimodal characteristics of truck load are analyzed and a probability model for a time interval t is obtained by fitting results and reliability theory. Then, a methodology is presented to combine earthquake load and truck load on a probabilistic basis. To illustrate this method, truck load and earthquake load combinations are used. Results conceptually illustrate that truck load and earthquake load are not dominant in southeast coastal areas of China, but the effect of their combination is. This methodology quantitatively demonstrates that the design is controlled by truck load in most ranges; that is, truck load is more important to bridge design in the region.

  15. Recent research and applications of GPS based technology for bridge health monitoring

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Today,long-span bridges are being designed to be more flexible and to resist extensive impacts from changes in temperature,severe wind gusts and earthquake tremors. Structural responses (especially displacement) of bridge structures are becoming increasingly important for the finite element (FE) modal updating,structural response prediction and safety evaluation. Methods of global displacement sensing were developed for these needs. This paper presents an overview of current research and development activities in the field of bridge health monitoring using the global positioning system (GPS). The GPS monitoring technology and its accuracy assessment method are also briefly described. Finally,existing problems and promising research efforts in the GPS based bridge health monitoring are discussed.

  16. Magnetic resonance imaging of flow and mass transfer in electrohydrodynamic liquid bridges

    CERN Document Server

    Wexler, Adam D; Fuchs, Elmar C; Woisetschläger, Jakob; Reiter, Gert; Fuchsjäger, Michael; Reiter, Ursula

    2016-01-01

    Here we report on the feasibility and use of magnetic resonance imaging based methods to the study of electrohydrodynamic (EHD) liquid bridges. High speed tomographic recordings through the longitudinal axis of water bridges were used to characterize the mass transfer dynamics, mixing, and flow structure. By filling one beaker with heavy water and the other with light water it was possible to track the spread of the proton signal throughout the total liquid volume. The mixing kinetics are different depending on where the light nuclei are located and proceeds faster when the anolyte is light water. Distinct flow and mixing regions are identified in the fluid volumes and it is shown that the EHD flow at the electrodes can be counteracted by the density difference between water isotopes. MR phase contrast imaging reveals that within the bridge section two separate counter propagating flows pass one above the other in the bridge.

  17. Mathematical Modeling of Local Scour at Slender and Wide Bridge Piers

    Directory of Open Access Journals (Sweden)

    Youssef I. Hafez

    2016-01-01

    Full Text Available Most existing equations for predicting local scour at bridge piers suffer from overprediction of the scour depths which results in higher foundation costs. To tackle this problem, a mathematical model for predicting bridge pier scour is developed herein based on an energy balance theory. The present study equation was compared to commonly used bridge scour equations using scour field data in USA. The developed equation has several advantages among which we have the following: it adds to the understanding of the physics of bridge pier scour, is valid for slender and wide piers, does not suffer from overprediction of scour depths, addresses clear water and live bed scour, and includes the effects of various characteristics of the bed material such as specific gravity (or density, porosity, size, and angle of repose. In addition, the developed equation accounts for the debris effect and aids in the design of scour mitigation methods such as collars, side bars, slots, and pier protective piles.

  18. Bridge Assessment and Health Monitoring with Distributed Long-Gauge FBG Sensors

    OpenAIRE

    Chunfeng Wan; Wan Hong; Jianxun Liu; Zhishen Wu; Zhaodong Xu; Shu Li

    2013-01-01

    Most sensors for structural testing and health monitoring are “point” sensors which strongly limit the ability to correct damage detection and structural assessment. In this paper, long-gauge FBG sensor which can sense the whole area within the gauge length is introduced. Bridge assessment and health monitoring with the microstrain distribution acquired by the distributed long-gauge FBG sensor are also studied. Experiments were conducted and application to a real prestressed box bridge was al...

  19. 鸭绿江界河公路大桥主桥桥型方案比选%Comparison and Selection of Proposed Bridge Types for Main Bridge of Yalu Boundary River Highway Bridge

    Institute of Scientific and Technical Information of China (English)

    吴宏业; 于传君

    2013-01-01

    The Yalu Boundary River Highway Bridge is an important international project connecting China and DPR Korea. In the light of the actual project conditions at the bridge site, two proposed bridge types for the main bridge of the bridge were compared, i. e. a steel box girder cable-stayed bridge with double pylons and double cable planes (the span arrangement being (86 + 229 + 636 + 229 + 86) m and the pylons being the H-shape concrete structures to be cast in situ) and a steel and concrete composite girder cable-stayed bridge with double pylons and double cable planes (the span arrangement being (87 + 228 + 636 + 228 + 87) m and the pylons being the inverted Y-shape concrete structures to be cast in situ). The plane link program Doctor Bridge V3. 2. 0 was used to respectively set up the finite element models for the two bridge types, the global mechanical behavior of the two bridges at completion and operation stages were analyzed and the construction convenience, durability and economy were analyzed as well. The results of the analysis show that the structural mechanical behavior of the steel box girder cable-stayed bridge is more advantageous, the construction is more convenient, the construction time schedule is shorter and the seismic performance is better and therefore the box girder bridge having 5 spans, double pylons and double planes is finally selected.%鸭绿江界河公路大桥是连接朝鲜的跨国性重要工程,结合桥址处实际工程条件,选取双塔双索面钢箱梁斜拉桥[跨径布置为(86+229+636+229+86)m,采用现浇H形桥塔]和双塔双索面钢-混结合梁斜拉桥[跨径布置为(87+228+636+228+87)m,采用现浇倒Y形桥塔]2种桥型方案进行比选.采用平面杆系程序桥梁博士V3.2.0分别建立2种方案的有限元模型,按整体成型对桥梁成桥阶段及运营阶段进行整体受力分析,并对2种方案的施工便利性、耐久性及经济性进行对比分析.分析结果表明,钢箱梁斜拉桥结

  20. Effects of bridge cable surface roughness and cross-sectional distortion on aerodynamic force coefficients

    DEFF Research Database (Denmark)

    Matteoni, G.; Georgakis, C.T.

    2012-01-01

    Theoretical and experimental investigations to date have assumed that bridge cables can be modeled as ideal circular cylinders and the associated aerodynamic coefficients are invariant with the wind angle-of-attack. On the other hand, bridge cables are normally characterized by local alterations...... of their inherent surface roughness and shape, which might present a significant disturbance for the surrounding wind flow. The present study focuses on the experimental determination, based on static wind tunnel tests, of the aerodynamic coefficients of full-scale bridge cable section models both perpendicular...... and inclined to the flow, for varying wind angles-of-attack. The wind tunnel test results demonstrate that the aerodynamic coefficients of bridge cables can be significantly affected by the wind angle-of-attack....

  1. Nano-catalysts: Bridging the gap between homogeneous and heterogeneous catalysis

    Science.gov (United States)

    Functionalized nanoparticles have emerged as sustainable alternatives to conventional materials, as robust, high-surface-area heterogeneous catalyst supports. We envisioned a catalyst system, which can bridge the homogenous and heterogeneous system. Postsynthetic surface modifica...

  2. On the Compatibility Between Quantum and Relativistic Effects in an Electromagnetic Bridge Theory

    CERN Document Server

    Auci, Massimo

    2010-01-01

    The Dipolar Electromagnetic Source (DEMS) model, based on the Poynting Vector Conjecture, conduces in Bridge Theory to a derivation of the Lorentz transformation connecting pairs of events. The results prove a full compatibility between quantum and relativistic effects.

  3. Bridging in contaminated transformer oil under DC and AC electric field

    International Nuclear Information System (INIS)

    There are two experimental set up have been established to investigate the bridging effect between two electrodes with different potentials under ac and dc voltages. This paper will explain the full details of the experimental setup and the results. These experiments carried out on pressboard particles under three different levels of ac and dc voltages. Several contamination levels have been investigated. Optical images of particle accumulation have been recorded along with associated conduction current measurement during experiments. At higher voltages the rate of bridge formation is increased along with an associated current increase. The major differences between ac and dc bridges are the shapes of the particle accumulation. The bridge formation rate for ac is slower than dc

  4. Chemically modified heparins inhibit fibrinogen-bridged indirect adhesion between tumor cells and platelets

    OpenAIRE

    Zheng, Sheng; Liu, Yan; Jiao, Yang; Min WEI; ZENG, XIANLU

    2011-01-01

    The interaction between platelets and tumor cells is critical for the hematogenous metastasis of tumor cells. We recently reported that fibrinogen was capable of bridging and enhancing the interaction of platelets and tumor cells under conditions of physical shear force. In the present study, we aimed to detect the effects of 8 chemically modified heparins on the binding of fibrinogen to platelets or tumor cells using flow cytometry assays, as well as the fibrinogen-bridged adhesion of platel...

  5. Seismic bridge pier analysis for pile foundation by force and displacement based approaches

    OpenAIRE

    Singh NP.R.; Vinayak Hemant Kumar

    2015-01-01

    Seismic analysis of bridge pier supported on pile foundation requires consideration of soil-pile-structure (kinematic and inertial) interactions. This paper presents the design forces generated for bridge piers with varying height and constant diameter for medium and soft soils in earthquake probability zones considering contribution of soil-pile-structure interactions by developed analytical approaches. The results have shown that the difference in base sh...

  6. Magnetic resonance imaging of flow and mass transfer in electrohydrodynamic liquid bridges

    OpenAIRE

    Adam D. Wexler; Drusova, Sandra; Fuchs, Elmar C; Woisetschläger, Jakob; Reiter, Gert; Fuchsjäger, Michael; Reiter, Ursula

    2016-01-01

    Here we report on the feasibility and use of magnetic resonance imaging based methods to the study of electrohydrodynamic (EHD) liquid bridges. High speed tomographic recordings through the longitudinal axis of water bridges were used to characterize the mass transfer dynamics, mixing, and flow structure. By filling one beaker with heavy water and the other with light water it was possible to track the spread of the proton signal throughout the total liquid volume. The mixing kinetics are dif...

  7. Foam-film-stabilized liquid bridge networks in evaporative lithography and wet granular matter

    KAUST Repository

    Vakarelski, Ivan Uriev

    2013-04-23

    Evaporative lithography using latex particle templates is a novel approach for the self-assembly of suspension-dispersed nanoparticles into ordered microwire networks. The phenomenon that drives the self-assembly process is the propagation of a network of interconnected liquid bridges between the template particles and the underlying substrate. With the aid of video microscopy, we demonstrate that these liquid bridges are in fact the border zone between the underlying substrate and foam films vertical to the substrate, which are formed during the evaporation of the liquid from the suspension. The stability of the foam films and thus the liquid bridge network stability are due to the presence of a small amount of surfactant in the evaporating solution. We show that the same type of foam-film-stabilized liquid bridge network can also propagate in 3D clusters of spherical particles, which has important implications for the understanding of wet granular matter. © 2013 American Chemical Society.

  8. Free vibrations of multi-girder and multi-cell box bridges with transverse deformations effects

    Science.gov (United States)

    Hamed, E.; Frostig, Y.

    2005-01-01

    A general mathematical approach is developed for the free vibration behaviour analysis of multi-girder and multi-cell box bridges with a single or multi span, including the effects of the transverse deformations of the bridge cross-section. The governing equations of motion and the corresponding boundary and continuity conditions are derived via the variational principle of virtual work following Hamilton's principle. The model is general and valid for any boundary and continuity conditions, and is applicable for multi-girder bridges with longitudinal and cross beams and for multi-cell box bridges. The warping and the distortion of the bridge cross-section effects are included in the proposed model. Closed-form solutions of the governing equations are derived and the Newton-Raphson method is used to determine the eigenfrequencies. Numerical examples are presented to validate the proposed model, and are also used to examine the accuracy of other approximate models used in the analysis of bridges. The results of the proposed model are validated through comparison with three-dimensional finite element models. The results reveal that the transverse deformations decrease the magnitudes of the eigenfrequencies of the torsional mode shapes, as well as the high flexural modes.

  9. Bridging patterns : An approach to bridge gaps between SE and HCI

    NARCIS (Netherlands)

    Folmer, E; van Welie, M; Bosch, J

    2006-01-01

    Adding usability improving solutions during late stage development is to some extent restricted by the software architecture. However, few software engineers and human-computer interaction engineers are aware of this important constraint and as a result avoidable rework is frequently necessary. In t

  10. The Future of the Technologies of Shell and spatial Structures. Bridges

    OpenAIRE

    Samartín, Avelino

    1998-01-01

    The objective of this lecture is try to predict the future of this important type of spatial structures. In this way the activities of the different IASS Technical Working Groups can be stimulated and coordinated in order to play a more relevant role in this future. To grasp a possible evolution of bridges it is convenient a reflection on the bridge history and on their present situation, particularly in relation to the different existing achievements.

  11. Static and fatigue investigation of second generation steel free bridge decks

    International Nuclear Information System (INIS)

    This paper outlines the static and fatigue behavior of two different cast-in-place second generation steel-free bridge decks, which are: hybrid carbon fiber reinforced polymer (CFRP); and glass fiber reinforced polymer (GFRP) and steel strap design. Although cast monolithically, the first deck slab was divided into three segments with different reinforcement configurations. All three segments were tested under a 222kN cyclic loading to investigate fatigue behavior. The second bridge deck comprised an internal panel and two cantilevers and was equipped with a civionics system. The internal panel static test that this paper deals with is useful in the development of fatigue theory derived from fatigue testing of the first bridge deck. Test results form the cyclic loading of the first bridge deck indicated that the cross-sectional area of the reinforcement used in the test bridge deck can be reduced by 40% based on the reinforcement provided in the deck under service loads. The hybrid system also reduced the development of longitudinal crack widths to approximately 0.4 mm under service conditions, compared to the cracks that occurred approximately halfway between adjacent bridge girders that were determined to be roughly 1 mm in several first generation steel-free bridge decks constructed in Canada. Civionics, also discussed in the paper, is a new term coined from Civil-Electronics, which is the application of electronics to civil structures. The Civionics Specifications (2004) developed by ISIS Canada researchers are a helpful design tool for engineers and contractors to develop civionics and structural health monitoring systems for civil infrastructure that will last the lifetime of a structure. The use of civionics for the second test bridge deck ensured the survival of 100% of the 63 internal sensors throughout the rigors of the construction and casting of the deck. (author)

  12. Damage Identification of Bridge Based on Modal Flexibility and Neural Network Improved by Particle Swarm Optimization

    OpenAIRE

    Hanbing Liu; Gang Song; Yubo Jiao; Peng Zhang; Xianqiang Wang

    2014-01-01

    An approach to identify damage of bridge utilizing modal flexibility and neural network optimized by particle swarm optimization (PSO) is presented. The method consists of two stages; modal flexibility indices are applied to damage localizing and neural network optimized by PSO is used to identify the damage severity. Numerical simulation of simply supported bridge is presented to demonstrate feasibility of the proposed method, while comparative analysis with traditional BP network is for its...

  13. Dynamic analysis of the train-bridge interaction: an accurate and efficient numerical method

    OpenAIRE

    Azevedo, A.; Neves, Sérgio; Calcada, R.

    2008-01-01

    The dynamic behavior of railway bridges carrying high-speed trains can be analyzed with or without the consideration of the vehicle's own structure. However, due to the amount of kinetic energy carried at high speeds, the train may interact significantly with the bridge, especially when resonance occurs. Equally important is the riding comfort and the stability of the track and train cars, which are usually the most critical limit states in the design of this type of structures...

  14. Fouling control mechanisms of demineralized water backwash: Reduction of charge screening and calcium bridging effects

    KAUST Repository

    Li, Sheng

    2011-12-01

    This paper investigates the impact of the ionic environment on the charge of colloidal natural organic matter (NOM) and ultrafiltration (UF) membranes (charge screening effect) and the calcium adsorption/bridging on new and fouled membranes (calcium bridging effect) by measuring the zeta potentials of membranes and colloidal NOM. Fouling experiments were conducted with natural water to determine whether the reduction of the charge screening effect and/or calcium bridging effect by backwashing with demineralized water can explain the observed reduction in fouling. Results show that the charge of both membranes and NOM, as measured by the zeta potential, became more negative at a lower pH and a lower concentration of electrolytes, in particular, divalent electrolytes. In addition, calcium also adsorbed onto the membranes, and consequently bridged colloidal NOM and membranes via binding with functional groups. The charge screening effect could be eliminated by flushing NOM and membranes with demineralized water, since a cation-free environment was established. However, only a limited amount of the calcium bridging connection was removed with demineralized water backwashes, so the calcium bridging effect mostly could not be eliminated. As demineralized water backwash was found to be effective in fouling control, it can be concluded that the reduction of the charge screening is the dominant mechanism for this. © 2011 Elsevier Ltd.

  15. Membrane bridging and hemifusion by denaturated Munc18.

    Directory of Open Access Journals (Sweden)

    Yi Xu

    Full Text Available Neuronal Munc18-1 and members of the Sec1/Munc18 (SM protein family play a critical function(s in intracellular membrane fusion together with SNARE proteins, but the mechanism of action of SM proteins remains highly enigmatic. During experiments designed to address this question employing a 7-nitrobenz-2-oxa-1,3-diazole (NBD fluorescence de-quenching assay that is widely used to study lipid mixing between reconstituted proteoliposomes, we observed that Munc18-1 from squid (sMunc18-1 was able to increase the apparent NBD fluorescence emission intensity even in the absence of SNARE proteins. Fluorescence emission scans and dynamic light scattering experiments show that this phenomenon arises at least in part from increased light scattering due to sMunc18-1-induced liposome clustering. Nuclear magnetic resonance and circular dichroism data suggest that, although native sMunc18-1 does not bind significantly to lipids, sMunc18-1 denaturation at 37 °C leads to insertion into membranes. The liposome clustering activity of sMunc18-1 can thus be attributed to its ability to bridge two membranes upon (perhaps partial denaturation; correspondingly, this activity is hindered by addition of glycerol. Cryo-electron microscopy shows that liposome clusters induced by sMunc18-1 include extended interfaces where the bilayers of two liposomes come into very close proximity, and clear hemifusion diaphragms. Although the physiological relevance of our results is uncertain, they emphasize the necessity of complementing fluorescence de-quenching assays with alternative experiments in studies of membrane fusion, as well as the importance of considering the potential effects of protein denaturation. In addition, our data suggest a novel mechanism of membrane hemifusion induced by amphipathic macromolecules that does not involve formation of a stalk intermediate.

  16. Feasibility and Costs of Natural Gas as a Bridge to Deep Decarbonization in the United States

    Science.gov (United States)

    Jones, A. D.; McJeon, H. C.; Muratori, M.; Shi, W.

    2015-12-01

    Achieving emissions reductions consistent with a 2 degree Celsius global warming target requires nearly complete replacement of traditional fossil fuel combustion with near-zero carbon energy technologies in the United States by 2050. There are multiple technological change pathways consistent with this deep decarbonization, including strategies that rely on renewable energy, nuclear, and carbon capture and storage (CCS) technologies. The replacement of coal-fired power plants with natural gas-fired power plants has also been suggested as a bridge strategy to achieve near-term emissions reduction targets. These gas plants, however, would need to be replaced by near-zero energy technologies or retrofitted with CCS by 2050 in order to achieve longer-term targets. Here we examine the costs and feasibility of a natural gas bridge strategy. Using the Global Change Assessment (GCAM) model, we develop multiple scenarios that each meet the recent US Intended Nationally Determined Contribution (INDC) to reduce GHG emissions by 26%-28% below its 2005 levels in 2025, as well as a deep decarbonization target of 80% emissions reductions below 1990 levels by 2050. We find that the gas bridge strategy requires that gas plants be retired on average 20 years earlier than their designed lifetime of 45 years, a potentially challenging outcome to achieve from a policy perspective. Using a more idealized model, we examine the net energy system costs of this gas bridge strategy compared to one in which near-zero energy technologies are deployed in the near tem. We explore the sensitivity of these cost results to four factors: the discount rate applied to future costs, the length (or start year) of the gas bridge, the relative capital cost of natural gas vs. near-zero energy technology, and the fuel price of natural gas. The discount rate and cost factors are found to be more important than the length of the bridge. However, we find an important interaction as well. At low discount rates

  17. Design and construction of the Aoba bridge; Aoba ohashi no keikaku to seko

    Energy Technology Data Exchange (ETDEWEB)

    Kuroki, H.; Wakamatsu, T. [Miyazaki Prefectural Government Office, Miyazaki (Japan); Akizuki, T. [P.S. Corp., Tokyo (Japan); Uchida, H. [Oriental Construction Co. Ltd., Tokyo (Japan)

    1997-05-30

    This paper describes the design and construction of a ferro-concrete fixed arch bridge (Aoba Bridge) in Takachiho Town, Miyazaki Prefecture. The bridge face height is 100 m above the river bed, wherein, since constructing roads for the construction is impossible near the site, and considerations were given on the scenic viewpoint, the bridge took a structure to stride the valley with a single span. The construction is characterized by adopting a construction method using truss and assembled arch simultaneously, and a cantilever overhanging erection using special large mobile erection vehicles. An optimum arrangement length in the simultaneous construction method was discussed on the length of the assembled arch. Since the site is in the quasi-national park where there is a promenade to enjoy nature under the bridge, excavation was carried out by using blasting and drilling machines simultaneously paying attention not to drop excavated rock lumps into the valley. Because the structure system makes extremely complicated changes from one time to another during the erection, the safety of construction was ensured by measuring stress and deformation in each construction phase and comparing the measurements with the planned values. Dynamic analyses and vibration tests were also carried out in each phase. The bridge was completed in December 1996 requiring four years without causing a single problem. The simultaneous truss and assembled arch using construction method was demonstrated for the first time in the world. 8 refs., 29 figs., 7 tabs.

  18. Active Control of Suspension Bridges

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

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

  19. Big data and high-performance analytics in structural health monitoring for bridge management

    Science.gov (United States)

    Alampalli, Sharada; Alampalli, Sandeep; Ettouney, Mohammed

    2016-04-01

    Structural Health Monitoring (SHM) can be a vital tool for effective bridge management. Combining large data sets from multiple sources to create a data-driven decision-making framework is crucial for the success of SHM. This paper presents a big data analytics framework that combines multiple data sets correlated with functional relatedness to convert data into actionable information that empowers risk-based decision-making. The integrated data environment incorporates near real-time streams of semi-structured data from remote sensors, historical visual inspection data, and observations from structural analysis models to monitor, assess, and manage risks associated with the aging bridge inventories. Accelerated processing of dataset is made possible by four technologies: cloud computing, relational database processing, support from NOSQL database, and in-memory analytics. The framework is being validated on a railroad corridor that can be subjected to multiple hazards. The framework enables to compute reliability indices for critical bridge components and individual bridge spans. In addition, framework includes a risk-based decision-making process that enumerate costs and consequences of poor bridge performance at span- and network-levels when rail networks are exposed to natural hazard events such as floods and earthquakes. Big data and high-performance analytics enable insights to assist bridge owners to address problems faster.

  20. Physical Properties of the Magellanic Bridge Tidal Remnant through Mapped Hα, [SII], and [NII] Emission

    Science.gov (United States)

    Barger, Kathleen; Haffner, L. Matthew

    2016-01-01

    We present the first kinematically resolved [S II] λ6716 and [N II] λ6583 emission maps of the entire Magellanic Bridge that were observed with the Wisconsin Hα Mapper Telescope. Combining these maps with the complementary Hα maps of Barger et al. (2013), we explore the temperature, sulfur and nitrogen ionization state, and sources of the ionization of the warm-ionized gas in the Magellanic Bridge, the SMC-Tail, and the LMC-Bridge interface region. Within the Magellanic Bridge, we find that the low velocity (+100 to +200 km s-1 ) and the high velocity (+200 to +300 km s-1 ) gas have different properties, suggesting that it is composed of at least two separate and coherent filaments. Within the high-velocity filament, a high-velocity ridge of gas—with different properties from the high-velocity structure—extends along the high-latitude edge of the Hα SMC-Tail to low latitude edge LMC-Bridge interface. This ridge coincides with a strip of early-type stars, suggesting that these stars are influencing this gas. We further find that the properties of both the SMC-Tail and LMC-Bridge interface regions have similar properties and therefore are likely affected by similar ionization sources.

  1. 桥型与环境的协调%The Coordination of Bridge Type and Environment

    Institute of Scientific and Technical Information of China (English)

    廖鸿华; 陶斌铮

    2013-01-01

      阐述了桥梁造型与环境的关系,不同桥型的形态特征以及与环境的协调。强调了在桥梁桥梁的设计不应只考虑桥承受荷载的能力,同时应考虑其造型及其与环境的协调。%This paper describes the relationship between bridge type with environment, the morphological characteristics of the different bridge type, as well as coordination with the environment. Stressed that it should not only be considered bridge load capacity in the design of bridge, taking into account its type and its harmony with the environment.

  2. Fatigue stress monitoring and analyses for steel box girder of Runyang Suspension Bridge

    Institute of Scientific and Technical Information of China (English)

    Ying WANG; Zhaoxia LI; Baijian WU

    2008-01-01

    The monitoring of fatigue stress of steel bridge is a key issue of bridge health monitoring and safety assessment. This paper aims to find out the strain history features of the girder components of Runyang Suspension Bridge (RYSB) under vehicle and environmental loading during its first year of service based on the strain-history data recorded by structural health monitoring system installed in the bridge. The fatigue stress spectrums of steel box girders under normal traffic load, heavy trucks and typhoon loads were studied as well as the correlation between varying strain and temperature based on real-time monitoring of temperature histories. The results show that, monitoring on local strain in health monitoring systems of RYSB can effectively provide the information on fatigue stresses. The range of the equivalent fatigue stress on the monitoring location of the bridge is currently low, mainly due to varying traffic loading and temper-ature. There exists significant correlation between varying temperature and mean value of fatigue stress. Effect of the passing of heavy trucks on bridge fatigue is quite signifi-cant since the value of the cumulative fatigue damage generated by heavy trucks is 10 to 100 times larger than that by normal traffic. Therefore, the effect on fatigue cumulative damage due to heavy trucks or overloaded vehicles needs to be monitored and paid much attention to.

  3. 77 FR 35323 - National Environmental Policy Act: Categorical Exclusions for Soil and Water Restoration Activities

    Science.gov (United States)

    2012-06-13

    ... natural channels and floodplains by removing water control structures, such as dikes, ditches, culverts..., or modifying water control structures such as, but not limited to, dams, levees, dikes,...

  4. 符夹铁路青龙山特大桥空间刚架设计%Design of Spatial Rigid Frame Structure of Qinglongshan Extra-long Bridge on Fujia Railway

    Institute of Scientific and Technical Information of China (English)

    侯伟

    2015-01-01

    With a view to bridge structures with small cross angle, there are many advantages of spatial rigid frame structures, such as lower construction height, high integral stiffness, less construction difficulty, convenient creation of a variety of landscape effects on side walls. Qinglongshan extra-long bridge is located in the soft soil foundation across Qingfu link railway and two underground culverts with a small oblique angle, which requires much on the space height under bridge and the foundation location. In order to achieve reasonable bridge design, the best bridge scheme is selected according basic bridge conditions, and design and calculation are conducted in perspective of spatial rigid frame with discontinuous foundation. The results show that the selected structure is reasonable and a new form of extension to the traditional rigid frame structure.%小角度交叉桥梁结构中,空间框架结构具有结构高度低、整体刚度大、施工难度小、侧墙可打造多种景观需求等优点。符夹铁路青龙山特大桥地处中软土地基,小角度斜向上跨青符铁路联络线和两个下穿涵洞,对桥下通行净空和基础位置设置有较高要求。为了合理设计大桥,根据桥梁基本情况进行桥型方案比选,并对基础间断布置的空间刚架方案进行设计计算论证。结果表明,所选结构形式合理且为传统刚架结构提供新的扩展形式。

  5. Inhibitory Effect of Bridged Nucleosides on Thermus aquaticus DNA Polymerase and Insight into the Binding Interactions.

    Directory of Open Access Journals (Sweden)

    Sung-Kun Kim

    Full Text Available Modified nucleosides have the potential to inhibit DNA polymerases for the treatment of viral infections and cancer. With the hope of developing potent drug candidates by the modification of the 2',4'-position of the ribose with the inclusion of a bridge, efforts were focused on the inhibition of Taq DNA polymerase using quantitative real time PCR, and the results revealed the significant inhibitory effects of 2',4'-bridged thymidine nucleoside on the polymerase. Study on the mode of inhibition revealed the competitive mechanism with which the 2',4'-bridged thymidine operates. With a Ki value of 9.7 ± 1.1 μM, the 2',4'-bridged thymidine proved to be a very promising inhibitor. Additionally, docking analysis showed that all the nucleosides including 2',4'-bridged thymidine were able to dock in the active site, indicating that the substrate analogs reflect a structural complementarity to the enzyme active site. The analysis also provided evidence that Asp610 was a key binding site for 2',4'-bridged thymidine. Molecular dynamics (MD simulations were performed to further understand the conformational variations of the binding. The root-mean-square deviation (RMSD values for the peptide backbone of the enzyme and the nitrogenous base of the inhibitor stabilized within 0.8 and 0.2 ns, respectively. Furthermore, the MD analysis indicates substantial conformational change in the ligand (inhibitor as the nitrogenous base rotated anticlockwise with respect to the sugar moiety, complemented by the formation of several new hydrogen bonds where Arg587 served as a pivot axis for binding formation. In conclusion, the active site inhibition of Taq DNA polymerase by 2',4'-bridged thymidine suggests the potential of bridged nucleosides as drug candidates.

  6. Bridge joint fabrication and validation for SST-1 PF coil winding pack

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, Upendra, E-mail: upendra@ipr.res.in; Sharma, A.N.; Patel, D.; Doshi, K.; Varmora, P.; Khristi, Y.; Pradhan, S.

    2014-12-15

    Highlights: • Prototype of bridge type joints fabricated and validated successfully. • Bridge type joints fabricated and validated on one of the SST-1 PF#3T coil successfully. • Joint resistance was measured with precision nano volt meter and PXI based data acquisition system. • Leak tightness of joint box was better than 3 × 10{sup −6} Pa m{sup 3} s{sup −1}. • The measured joint resistance of bridge type joint was ∼1.6 nano ohm. - Abstract: A novel concept of bridge joint for Poloidal field (PF) magnet of SST-1 with damaged winding pack has been realized. This joint has been fabricated on 5th and 6th layers of PF#3T coil winding pack (WP) after validation at 10 kA at liquid helium temperature of 4.2 K in current lead test chamber. The joint resistance of bridge joint was measured ∼1.6 nΩ at flat top DC current of 10 kA. This type of joint could be economically useful for revival of a shorted and damaged WP superconducting PF magnets of Tokamaks. In this paper, details of bridge joint design, fabrication and validations are discussed.

  7. Effects of structural characterizations on fragility functions of bridges subject to seismic shaking and lateral spreading

    Institute of Scientific and Technical Information of China (English)

    Jian Zhang; Yili Huo; Scott J.Brandenberg; Pirooz Kashighandi

    2008-01-01

    This paper evaluates the seismic vulnerability of different classes of typical bridges in California when subjected to seismic shaking or liquefaction-induced lateral spreading.The detailed structural configurations in terms of superstructure type,connection,continuity at support and foundation type,etc.render different damage resistant capability.Six classes of bridges are established based on their anticipated failure mechanisms under earthquake shaking.The numerical models that are capable of simulating the complex soil-structure interaction effects,nonlinear behavior of columns and connections are developed for each bridge class.The dynamic responses are obtained using nonlinear time history analyses for a suite of 250 earthquake motions with increasing intensity.An equivalent static analysis procedure is also implemented to evaluate the vulnerability of the bridges when subjected to liquefaction-induced lateral spreading.Fragility functions for each bridge class are derived and compared for both seismic shaking (based on nonlinear dynamic analyses) and lateral spreading (based on equivalent static analyses) for different performance states.The study finds that the fragility functions due to either ground shaking or lateral spreading show significant correlation with the structural characterizations,but differences emerge for ground shaking and lateral spreading conditions.Structural properties that will mostly affect the bridges' damage resistant capacity are also idantified.

  8. Efforts to Bridge the Gap between Research and Practice in Social Work: Precedents and Prospects: Keynote Address at the Bridging the Gap Symposium

    Science.gov (United States)

    Rubin, Allen

    2015-01-01

    This keynote address discusses previous and ongoing efforts to reduce the persistent gap between research and practice in social work and offers recommendations for further bridging that gap. Key among those recommendations is the need to conduct descriptive outcome studies of efforts to adapt research-supported interventions in everyday practice…

  9. Structure-borne noise of railway composite bridge: Numerical simulation and experimental validation

    Science.gov (United States)

    Li, Xiaozhen; Liu, Quanmin; Pei, Shiling; Song, Lizhong; Zhang, Xun

    2015-09-01

    In order to investigate the characteristics of the noise from steel-concrete composite bridges under high-speed train loading, a model used to predict the bridge-borne noise is established and validated through a field experiment. The numerical model for noise prediction is developed based on the combination of spatial train-track-bridge coupled vibration theory and Statistical Energy Analysis (SEA). Firstly, train-track-bridge coupled vibration is adopted to obtain the velocity time history of the bridge deck vibration. Then, the velocity time history is transferred into frequency domain through FFT to serve as the vibratory energy of SEA deck subsystems. Finally, the transmission of the vibratory energy is obtained by solving the energy balance equations of SEA, and the sound radiation is computed using the vibro-acoustic theory. The numerically computed noise level is verified by a field measurement. It is determined that the dominant frequency of steel-concrete composite bridge-borne noise is 20-1000 Hz. The noise from the bottom flange of steel longitudinal girder is less than other components in the whole frequency bands, while the noise from web of steel longitudinal girder is dominant in high frequency range above 315 Hz. The noise from concrete deck dominates in low-frequency domain ranges from 80 Hz to 160 Hz.

  10. Principles of Bridge Reliability

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Nowak, Andrzej S.

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

  11. The floating water bridge

    International Nuclear Information System (INIS)

    When high voltage is applied to distilled water filled in two glass beakers which are in contact, a stable water connection forms spontaneously, giving the impression of a floating water bridge. A detailed experimental analysis reveals static and dynamic structures as well as heat and mass transfer through this bridge

  12. Bridging the divide between genomic science and indigenous peoples.

    Science.gov (United States)

    Jacobs, Bette; Roffenbender, Jason; Collmann, Jeff; Cherry, Kate; Bitsói, LeManuel Lee; Bassett, Kim; Evans, Charles H

    2010-01-01

    The new science of genomics endeavors to chart the genomes of individuals around the world, with the dual goals of understanding the role genetic factors play in human health and solving problems of disease and disability. From the perspective of indigenous peoples and developing countries, the promises and perils of genomic science appear against a backdrop of global health disparity and political vulnerability. These conditions pose a dilemma for many communities when attempting to decide about participating in genomic research or any other biomedical research. Genomic research offers the possibility of improved technologies for managing the acute and chronic diseases that plague their members. Yet, the history of particularly biomedical research among people in indigenous and developing nations offers salient examples of unethical practice, misuse of data, and failed promises. This dilemma creates risks for communities who decide either to participate or not to participate in genomic science research. Some argue that the history of poor scientific practice justifies refusal to join genomic research projects. Others argue that disease poses such great threats to the well-being of people in indigenous communities and developing nations that not participating in genomic research risks irrevocable harm. Thus, some communities particularly among indigenous peoples have declined to participate as subjects in genomic research. At the same time, some communities have begun developing new guidelines, procedures, and practices for engaging with the scientific community that offer opportunities to bridge the gap between genomic science and indigenous and/or developing communities. Four new approaches warrant special attention and further support: consulting with local communities; negotiating the complexities of consent; training members of local communities in science and health care; and training scientists to work with indigenous communities. Implicit is a new

  13. Schools In Board - Bridging Arctic Research And Environmental Science Education

    Science.gov (United States)

    Barber, D. G.; Barber, L.

    2008-12-01

    Schools on Board (www.arcticnet.ulaval.ca) was created in 2002 to address the outreach objectives of a network of Canadian scientists conducting research in the High Arctic. The program was piloted with great success with the 2004 research program called the Canadian Arctic Shelf Study (CASES). Since then, the S/B program continues as an integral outreach program of the Canadian Network of Centres of Excellence (NCE) known as ArcticNet. The primary objective of the program is to bridge Arctic climate change research with science and environmental education in the public school system. It is a vehicle for scientists and graduate students to share their research program with high schools and the general public. The program encourages schools to include Arctic Sciences into their science programs by linking Arctic research to existing curriculum, providing resources and opportunities to send high school students and teachers into the Arctic to participate in a science expedition on board the Canadian research icebreaker CCGS Amundsen. The field program is an adventure into Arctic research that exposes students and teachers to the objectives and methods of numerous science teams representing a number of research disciplines and institutions from across Canada and beyond. Face-to-face interactions with scientists of all levels (masters, PhD's, researchers, CRC chairs), hands-on experiences in the field and in the labs, and access to state-of-the-art scientific instrumentation, combine to create a powerful learning environment. In addition to hands-on research activities the program introduces participants to many aspects of Canada's North, including local knowledge related to climate change, culture, history, and politics - within the educational program on the ship and the planned visits to Northern communities. During International Polar Year (IPY) Schools on Board collaborated with international researchers and northern agencies from 11 countries to offer one

  14. Formation and base hydrolysis of oxidimethaneamine bridges in CoIII-amine complexes.

    Science.gov (United States)

    Morgenstern, Bernd; Neis, Christian; Zaschka, Anton; Romba, Jens; Weyhermüller, Thomas; Hegetschweiler, Kaspar

    2013-10-21

    cis-[CoL2](3+) (1a(3+)), trans-[CoL2](3+) (2a(3+)), cis-[Co(MeL)2](3+) (1b(3+)), and trans-[Co(MeL)2](3+) (2b(3+)), L = 1,4-diazepan-6-amine (daza) and MeL = 6-methyl-1,4-diazepan-6-amine (Medaza), were allowed to react as templates in acetonitrile with paraformaldehyde and triethylamine. Several Co(III) complexes, where two adjacent amino groups of two ligand moieties are interlinked by an oxidimethaneamine bridge, were obtained. Connection of a primary with a secondary amino group (prim-sec bridging) was found to be predominant. The singly and doubly bridged daza- and Medaza-derivatives 7a(3+), 9a(3+) and 7b(3+), 9b(3+) were characterized by crystal-structure analysis. The bridging process resulted in a slight lengthening of the mean Co-N distance, a red shift of the A1g-T1g transition, and an increase of the Co(III)/Co(II) reduction potential. Several minor components, which could be only partially separated by chromatographic methods, were also formed. The daza-derivatives 6a(3+) (prim-prim bridged) and 10a(3+) (bidentate coordination of one daza frame) formed in small quantities. The Medaza derivatives 3b(3+) and 4b(3+) (trans configuration of the Medaza frames, with additional pending carbinolamino groups), and 8b(3+) (with a methylideneimino group) represent intermediates of the condensation process. Their structure was again corroborated by X-ray diffraction. All bridged species (6a(3+), 7a(3+), 7b(3+), 8b(3+), 9a(3+), 9b(3+), and 10a(3+)) exhibited exclusively a cis orientation of the two diazepane frames, even if the trans configured 2a(3+) or 2b(3+) were used as starting materials. Molecular mechanics calculations indicate that in the bridged species with a trans configuration steric strain is substantially more pronounced. In alkaline aqueous media, 9a(3+) and 9b(3+) revealed a complete degradation of the bridges whereby the original 1a(3+) and 1b(3+) reformed. The pseudo-first-order rate constant k(obs) of the degradation reaction was found to depend

  15. Vibration monitoring of long bridges and their expansion joints and seismic devices

    Directory of Open Access Journals (Sweden)

    Islami Kleidi

    2015-01-01

    Full Text Available This paper presents a number of recently installed Structural Health Monitoring (SHM systems: a on a 2km double suspension bridge; b on a long railway viaduct that has experienced cracking; and c on a steel arch bridge in a seismically active area. Damage detection techniques have been applied based on high-frequency measurements of vibrations, pressure and strain, enabling a proper understanding of the structures’ behaviour to be gained. The diverse range of applications presented, designed in collaboration with structure owners and design engineers, includes damage detection on expansion joints of suspension bridges, crack analysis and correlation with accelerations of high-speed trains, and high-frequency performance monitoring of seismic devices. These case studies, based on both static and dynamic approaches, demonstrate the usefulness and ease of use of such systems, and the enormous gains in efficiency they offer.

  16. Bridging the gap between laboratory and clinic in child and adolescent psychotherapy.

    Science.gov (United States)

    Weisz, J R; Donenberg, G R; Han, S S; Weiss, B

    1995-10-01

    Meta-analyses of laboratory outcome studies reveal beneficial effects of psychotherapy with children and adolescents. However, the research therapy in most of those lab studies differs from everyday clinic therapy in several ways, and the 9 studies of clinic therapy the authors have found show markedly poorer outcomes than research therapy studies. These findings suggest a need to bridge the long-standing gap between outcome researchers and clinicians. Three kinds of bridging research are proposed and illustrated: (a) enriching the research data base on treatment effects by practitioners in clinical settings--including private practice and health maintenance organizations, (b) identifying features of research therapy that account for positive outcomes and applying those features to clinical practice, and (c) exporting lab-tested treatments to clinics and assessing their effects with referred youths. If these bridging strategies were widely adopted, despite the numerous obstacles described herein, real progress might be made toward more effective treatment in clinical practice. PMID:7593861

  17. Science For Sendai - Bridging the gap between research and application

    Science.gov (United States)

    Rees, J.

    2015-12-01

    Disasters have an enormous cost in lives and livelihoods, but the use of rigorous evidence-based scientific approaches to minimise their impact remains poor. Vast amounts of science which could be readily applied for disaster risk reduction (DRR) is under-utilised, if used at all. Previous international agreements have failed to change this picture, but there is a clear call from the international community that the 2015 Sendai framework should make a difference; it is thus re-appraising how to bridge the chasm that exists between DRR relevant scientists and potential users of their research. There is widespread recognition of the need for risk affected countries and communities to engage in science-based decision-making, but several barriers, such as a lack of infrastructure or necessary skills, institutions, and enforcement of science-based policies require significant attention. There are now incentives for governments to respond: the framework has science embedded throughout and it sets-out national targets against which science uptake can be monitored; similarly, widening access to insurance also demands sound science. Advances such as open-data and models, increasing computational capacity, expanding networks, evolving diverse mobile technologies and the other multiple facets of the big data agenda, also should drive change. So, how does the scientific community need to adapt? Whilst vast amounts of 'DRR-relevant' science has been produced, too little of it can be readily used in DRR science. Much remains highly disciplinary and focused on analysis of limited distributions or single processes with a small number of agents; by contrast real-world DRR problems are commonly complex, with multiple drivers and uncertainties. There is a major need for a trans-disciplinary DRR-focused risk research agenda to evolve. Not only do research funders need to develop and resource risk research, but researchers themselves need to identify that focussing on the bigger risk

  18. Evaluation of seismic damage to bridges and highway systems in Shelby County, Tennessee

    Science.gov (United States)

    Jernigan, John Bailey

    Past earthquakes have demonstrated that bridges are one of the most vulnerable components of highway transportation systems. In addition to bridges, roadways may also be subject to damage, particularly in an area prone to earthquake-induced liquefaction. As a consequence, the highway transportation systems after an earthquake might be impaired and the post-earthquake emergency response might be compromised. Furthermore, the impact on the regional economy might be very significant from the damage to highway systems. Since highway transportation systems are critical lifelines for people living in an urban area, it is important to evaluate the vulnerability of bridges and highway systems in earthquake-prone regions. Memphis and Shelby County, Tennessee are located close to the southwestern segment of the New Madrid seismic zone (NMSZ). This zone produced three of the largest earthquakes in North America in 1811--1812. Presently, the NMSZ is still active and is considered by engineers, seismologists, and public officials as the most hazardous seismic zone in the central and eastern United States. Bridges in the Memphis area were generally not designed for seismic resistance until 1990. Therefore, the majority of existing bridges might suffer damage from earthquakes occurring in the NMSZ. The overall objective of this study is to evaluate the expected damage to bridges and roadways on the major routes in Memphis and Shelby County resulting from New Madrid earthquakes with the aid of geographic information system (GIS) technology. The road network selected for this study includes all the Interstate highway system, all the primary and secondary routes maintained by the state, and most of the major arterial routes. There are 452 bridges on the selected roadway systems and data pertinent to these bridges and roadway systems were collected and implemented as a GIS database. The bridges in the Memphis area were classified into several types and damage states were determined

  19. Analysis, prediction, and case studies of early-age cracking in bridge decks

    Science.gov (United States)

    ElSafty, Adel; Graeff, Matthew K.; El-Gharib, Georges; Abdel-Mohti, Ahmed; Mike Jackson, N.

    2016-06-01

    Early-age cracking can adversely affect strength, serviceability, and durability of concrete bridge decks. Early age is defined as the period after final setting, during which concrete properties change rapidly. Many factors can cause early-age bridge deck cracking including temperature change, hydration, plastic shrinkage, autogenous shrinkage, and drying shrinkage. The cracking may also increase the effect of freeze and thaw cycles and may lead to corrosion of reinforcement. This research paper presents an analysis of causes and factors affecting early-age cracking. It also provides a tool developed to predict the likelihood and initiation of early-age cracking of concrete bridge decks. Understanding the concrete properties is essential so that the developed tool can accurately model the mechanisms contributing to the cracking of concrete bridge decks. The user interface of the implemented computer Excel program enables the user to input the properties of the concrete being monitored. The research study and the developed spreadsheet were used to comprehensively investigate the issue of concrete deck cracking. The spreadsheet is designed to be a user-friendly calculation tool for concrete mixture proportioning, temperature prediction, thermal analysis, and tensile cracking prediction. The study also provides review and makes recommendations on the deck cracking based mainly on the Florida Department of Transportation specifications and Structures Design Guidelines, and Bridge Design Manuals of other states. The results were also compared with that of other commercially available software programs that predict early-age cracking in concrete slabs, concrete pavement, and reinforced concrete bridge decks. The outcome of this study can identify a set of recommendations to limit the deck cracking problem and maintain a longer service life of bridges.

  20. Bridges and barriers to successful transitioning as perceived by adolescents and young adults with Asperger syndrome.

    Science.gov (United States)

    Giarelli, Ellen; Ruttenberg, Jean; Segal, Andrea

    2013-01-01

    In this thematic content analysis we examined the expectations, and perceived facilitators of (referred to as bridges) and barriers to transition to community as reported by adolescents and young adults with Asperger syndrome. Participants were adolescents/young adults, ages 18-23 years were from the East Coast of the United States. Seventy percent of adolescents hoped for employment (n = 10). Thirty percent desired to find a partner and raise a family. Perceived barriers were: self-assessed behavioral problems, self-assessed associated features, other personal factors, and institutional factors. Bridges to facilitate transition were: accommodations in the community, cognitive abilities, personal qualities/strengths, and mentor's qualities.

  1. Non-destructive inspection protocol for reinforced concrete barriers and bridge railings

    Science.gov (United States)

    Chintakunta, Satish R.; Boone, Shane D.

    2014-02-01

    Reinforced concrete highway barriers and bridge railings serve to prevent errant vehicles from departing the travel way at grade separations. Despite the important role that they play in maintaining safety and their ubiquitous nature, barrier inspection rarely moves beyond visual inspection. In August 2008, a tractor-trailer fatally departed William Preston Lane, Jr. Memorial Bridge after it dislodged a section of the bridge barrier. Investigations following the accident identified significant corrosion of the anchor bolts attaching the bridge railing to the bridge deck. As a result of the information gathered during its investigation of the accident, the National Transportation Safety Board (NTSB) made recommendations to the Federal Highway Administration concerning Non-Destructive Evaluation (NDE) of concrete bridge railings. The Center for nondestructive evaluation (NDE) at Turner Fairbank Highway Research Center in McLean, VA is currently evaluating feasibility of using four technologies - ground penetrating radar (GPR), ultrasonic pulse-echo, digital radiography and infrared thermal imaging methods to develop bridge inspection methods that augment visual inspections, offer reliable measurement techniques, and are practical, both in terms of time and cost, for field inspection work. Controlled samples containing predefined corrosion levels in reinforcing steel were embedded at barrier connection points for laboratory testing. All four NDE techniques were used in the initial phase I testing. An inspection protocol for detecting and measuring the corrosion of reinforced steel embedded in the anchorage system will be developed as part of phase II research. The identified technologies shall be further developed for field testing utilizing a structure with a barrier in good condition and a structure with a barrier in poor condition.

  2. On maintenance strategies of roads and bridges%谈公路桥梁养护对策

    Institute of Scientific and Technical Information of China (English)

    赵文峰

    2015-01-01

    The paper analyzes the meaning and aims of the road and bridge maintenance,illustrates factual maintenance measures of bridges and roads from the bridge beam maintenance,bridge pier maintenance,and deck maintenance,so as to prolong the life of roads and bridges and re-duce the times and cost of the roads and bridge maintenance by the maintenance measures.%分析了公路桥梁养护的意义及目的,从桥梁梁板养护、桥梁墩台养护、桥面铺装养护三方面,阐述了公路桥梁的具体养护措施,以延长公路桥梁的使用年限,减少公路桥梁修复的次数与成本。

  3. Mechanics model of additional longitudinal force transmission between bridges and continuously welded rails with small resistance fasteners

    Institute of Scientific and Technical Information of China (English)

    徐庆元; 周小林; 曾志平; 杨小礼

    2004-01-01

    A new mechanics model, which reveals additional longitudinal force transmission between the continuously welded rails and the bridges, is established on the fact that the influence of the mutual relative displacement among the rail, the sleeper and the beam is taken into account. An example is presented and numerical results are compared. The results show that the additional longitudinal forces calculated with the new model are less than those of the previous, especially in the case of the flexible pier bridges. The new model is also suitable for the analysis of the additional longitudinal force transmission between rails and bridges of ballastless track with small resistance fasteners without taking the sleeper displacement into account, and compared with the ballast bridges, the ballastless bridges have a much stronger additional longitudinal force transmission between the continuously welded rails and the bridges.

  4. Integration of computer imaging and sensor data for structural health monitoring of bridges

    International Nuclear Information System (INIS)

    The condition of civil infrastructure systems (CIS) changes over their life cycle for different reasons such as damage, overloading, severe environmental inputs, and ageing due normal continued use. The structural performance often decreases as a result of the change in condition. Objective condition assessment and performance evaluation are challenging activities since they require some type of monitoring to track the response over a period of time. In this paper, integrated use of video images and sensor data in the context of structural health monitoring is demonstrated as promising technologies for the safety of civil structures in general and bridges in particular. First, the challenges and possible solutions to using video images and computer vision techniques for structural health monitoring are presented. Then, the synchronized image and sensing data are analyzed to obtain unit influence line (UIL) as an index for monitoring bridge behavior under identified loading conditions. Subsequently, the UCF 4-span bridge model is used to demonstrate the integration and implementation of imaging devices and traditional sensing technology with UIL for evaluating and tracking the bridge behavior. It is shown that video images and computer vision techniques can be used to detect, classify and track different vehicles with synchronized sensor measurements to establish an input–output relationship to determine the normalized response of the bridge

  5. Extension of semi-analytical approach to determine natural frequencies and mode shapes of multi-span orthotropic bridge deck

    OpenAIRE

    Rezaiguia, Abdelouahab; Fisli, Y.; Ellagoune, S.; et al

    2012-01-01

    This paper extends a single equation, semi-analytical approach for three-span bridges to multispan ones for the rapid and precise determination of natural frequencies and natural mode shapes of an orthotropic, multi-span plate. This method can be used to study the dynamic interaction between bridges and vehicles. It is based on the modal superposition method taking into account intermodal coupling to determine natural frequencies and mode shapes of a bridge deck. In this paper, a four- and a ...

  6. Grey cast iron as construction material of bridges from the 18th and 19th century

    Directory of Open Access Journals (Sweden)

    J. Rabiega

    2011-04-01

    Full Text Available Many bridges and railroad viaducts, which have been operated at the western and southern regions of Poland, were erected at the end ofthe 18th or beginning of the 19th century. In recent years they undergo overhauls and renovations requiring familiarity with the construction materials they have been made of. It is necessary for estimation of their load capacity (possible reinforcements and determining their suitability for further utilisation. Among the materials in the old bridges the puddled steels and cast irons predominate. Aim of the work is identification and documentation of microstructure and selected properties of the cast irons used for production of parts for the bridge in Łażany, the Old Mieszczański Bridge in Wrocław, the hanging bridge in Ozimek, as well as the columnar piers of the railroad viaduct in Wrocław. Using the methods of light microscopy and scanning electron microscopy, as well as the results of hardness measurements and chemical analysis, it has been shown that the objects have been built of grey cast iron with flake graphite having the ferritic-pearlitic or pearlitic matrix. The diversification of their chemical analysis resulting from the type, size and geometry of the cast parts was indicated.The tested materials fulfil requirements of the contemporary standards related to grey cast irons of the EN-GJL-100 and EN-GJL-150grades.

  7. Endodontics pastes formulated with copaiba oil: action on oral microbiota and dentin bridge formation in dogs

    Directory of Open Access Journals (Sweden)

    Fernanda Gosuen Gonçalves Dias

    2015-06-01

    Full Text Available This study analysed the effect of pastes formulated with calcium hydroxide P.A. and different vehicles (saline solution - paste A and Copaifera langsdorffii Desfon oil - paste B on oral microorganisms and dentin bridge formation in dogs. The antimicrobial action of the pastes and their components was analysed by the minimum inhibitory concentration in agar gel technique. The components were diluted and tested on fifteen standard strains of microorganisms associated with endodontic diseases. The microorganisms were cultivated and after incubation data was analysed using One-Way ANOVA and Turkey's test (P≤0.05. Four superior incisors of ten animals were used to evaluate dentin bridge formation. Two incisors were capped with paste A (GA and two with paste B (GB. After 90 days, the teeth were extracted for histological analysis and the degree of dentin bridge formation evaluated. Data was analysed by the Kruskal-Wallis test (P<0.05. The pastes and their components were classified in the following decreasing order of antimicrobial action: calcium hydroxide P.A., paste A, paste B and Copaifera langsdorffii Desfon oil. Calcium hydroxide P.A. showed significantly higher antimicrobial action than the pastes or their vehicles. No significant difference was observed between the two pastes in dentin bridge formation. Based on the microorganisms studied, it can be concluded that the pastes analysed showed similar antimicrobial potential but differed significantly from their individual components. No significant difference was observed in dentin bridge formation between the different pastes tested.

  8. Bridge Management Systems

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

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

  9. Tidal Energy Conversion Installation at an Estuarine Bridge Site: Resource Evaluation and Energy Production Estimate

    Science.gov (United States)

    Wosnik, M.; Gagnon, I.; Baldwin, K.; Bell, E.

    2015-12-01

    The "Living Bridge" project aims to create a self-diagnosing, self-reporting "smart bridge" powered by a local renewable energy source, tidal energy - transforming Memorial Bridge, a vertical lift bridge over the tidal Piscataqua River connecting Portsmouth, NH and Kittery, ME, into a living laboratory for researchers, engineers, scientists, and the community. The Living Bridge project includes the installation of a tidal turbine at the Memorial Bridge. The energy converted by the turbine will power structural health monitoring, environmental and underwater instrumentation. Utilizing locally available tidal energy can make bridge operation more sustainable, can "harden" transportation infrastructure against prolonged grid outages and can demonstrate a prototype of an "estuarine bridge of the future". A spatio-temporal tidal energy resource assessment was performed using long term bottom-deployed Acoustic Doppler Current Profilers (ADCP) at two locations: near the planned deployment location in 2013-14 for 123 days and mid-channel in 2007 for 35 days. Data were evaluated to determine the amount of available kinetic energy that can be converted into usable electrical energy on the bridge. Changes in available kinetic energy with ebb/flood and spring/neap tidal cycles and electrical energy demand were analyzed. The target deployment site exhibited significantly more energetic ebb tides than flood tides, which can be explained by the local bathymetry of the tidal estuary. A system model is used to calculate the net energy savings using various tidal generator and battery bank configurations. Different resource evaluation methodologies were also analyzed, e.g., using a representative ADCP "bin" vs. a more refined, turbine-geometry-specific methodology, and using static bin height vs. bin height that move w.r.t. the free surface throughout a tidal cycle (representative of a bottom-fixed or floating turbine deployment, respectively). ADCP operating frequencies and bin

  10. Field measurement on wind characteristic and buffeting response of the Runyang Suspension Bridge during typhoon Matsa

    Institute of Scientific and Technical Information of China (English)

    WANG Hao; LI AiQun; GUO Tong; XIE Jing

    2009-01-01

    Field measurement on wind characteristic and buffeting response of existing bridge is of great value to the development of bridge wind engineering, and the structural health monitoring system (SHMS) em-ployed in many long-span bridges provide a research basis for the field measurement. In order to pro-vide reliable basis for wind resistant evaluation of Runyang Suspension Bridge (RSB), two anemome-ters and 85 accelerometers were installed in the SliMS of RSB. In August 2005, Typhoon Matsa crossed over Jiangsu, the SHMS timely recorded the typhoon and structural vibration responses. In this paper by using the time-frequency technique and statistical theory, the recorded data were analyzed to obtain the strong wind characteristics, the buffeting response characteristics of the cable and deck, and the variation of buffeting response RMS versus wind speed. Results obtained in this study can be em-ployed to validate the credibility of current buffeting response analysis theory techniques, and provide reference values for wind resistant evaluation of other long-span bridges.

  11. Coupled Vibration of Long-Span Railway Curved Girder Bridges and Vehicles

    Institute of Scientific and Technical Information of China (English)

    Shan Deshan; Li Qiao

    2005-01-01

    The structure of a long curved girder bridge is represented with a three-dimensional curved finite element model. Each 4-axle vehicle is modeled by a dynamic system of 35 degrees of freedom. The random irregularities of the track are generated from a power spectral density function under the given track condition. The dynamic interaction between the bridge and train is realized through the contact forces between the wheels and track. Then based on these models, the coupled equations of motion are solved by applying the time-integration and iteration techniques to the coupled system. The proposed formulation and the associated computer program are then applied to a real curved girder bridge. The dynamic responses of the bridge-vehicle system and the derailments and offload factors related to the riding and running safeties of vehicles are computed. The results show that the formulation presented in this paper can well predict dynamic behaviors of both bridge and train with reasonable computation efforts.

  12. Field measurement on wind characteristic and buffeting response of the Runyang Suspension Bridge during typhoon Matsa

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Field measurement on wind characteristic and buffeting response of existing bridge is of great value to the development of bridge wind engineering,and the structural health monitoring system(SHMS) em-ployed in many long-span bridges provide a research basis for the field measurement.In order to pro-vide reliable basis for wind resistant evaluation of Runyang Suspension Bridge(RSB),two anemome-ters and 85 accelerometers were installed in the SHMS of RSB.In August 2005,Typhoon Matsa crossed over Jiangsu,the SHMS timely recorded the typhoon and structural vibration responses.In this paper by using the time-frequency technique and statistical theory,the recorded data were analyzed to obtain the strong wind characteristics,the buffeting response characteristics of the cable and deck,and the variation of buffeting response RMS versus wind speed.Results obtained in this study can be em-ployed to validate the credibility of current buffeting response analysis theory techniques,and provide reference values for wind resistant evaluation of other long-span bridges.

  13. Probabilistic sensitivity analysis of two suspension bridges in Istanbul, Turkey to near- and far-fault ground motion

    OpenAIRE

    Çavdar, Ö.

    2012-01-01

    The aim of this paper is to compare the near-fault and far-fault ground motion effects on the probabilistic sensitivity dynamic responses of two suspension bridges in Istanbul. Two different types of suspension bridges are selected to investigate the near-fault (NF) and far-fault (FF) ground motion effects on the bridge sensitivity responses. NF and FF strong ground motion records, which have approximately identical peak ground accelerations, of the Kocaeli (1999) earthquake are selected for ...

  14. Full scale monitoring of wind and traffic induced response of a suspension bridge

    Directory of Open Access Journals (Sweden)

    Cheynet Etienne

    2015-01-01

    Full Text Available This paper presents a full-scale analysis of wind and traffic-induced vibrations of a long-span suspension bridge in complex terrain. Several wind and acceleration sensors have been installed along the main span on Lysefjord Bridge in Norway. In the present study, three days of continuous records are analysed. Traffic-induced vibrations are dominant at low and moderated wind speed, with non-negligible effects on the overall bridge response for heavy vehicles only. Traffic and wind-induced vibrations are compared in terms of root mean square of the acceleration response, and three simples approaches are proposed to isolate records dominated by wind-induced vibration. The first one relies on the separation of nocturnal and diurnal samples. The second one is based on the evaluation of the time-varying root mean square of the acceleration response. The last one evaluates the relative importance of the high frequency domain of the acceleration bridge response. It appears that traffic-induced vibrations may have to be taken into account for the buffeting analysis of long-span bridge under moderated wind.

  15. Streambed scour evaluations and conditions at selected bridge sites in Alaska, 2012

    Science.gov (United States)

    Beebee, Robin A.; Schauer, Paul V.

    2015-11-19

    Streambed scour potential was evaluated at 18 river- and stream-spanning bridges in Alaska that have unknown foundation details or a lack of existing scour analysis. All sites were evaluated for stream stability and long-term scour potential. Contraction scour and abutment scour were calculated for 17 bridges, and pier scour was calculated for 7 bridges that had piers. Vertical contraction (pressure flow) scour was calculated for sites with overtopping floods (where the modeled water surface was higher than the superstructure of the bridge). In most cases, hydraulic models of the 1- and 0.2-percent annual exceedance probability floods (also known as the 100- and 500-year floods, respectively) were used to derive hydraulic variables for the scour calculations. Alternate flood values were used in scour calculations for sites where smaller floods overtopped a bridge or where standard flood-frequency estimation techniques did not apply. Scour was also calculated for large recorded floods at several sites. Equations for scour in cohesive soils were used for sites where streambed sediment was silt-sized or smaller.

  16. GFRP seismic strengthening and structural heath monitoring of Portage Creek Bridge concrete columns

    International Nuclear Information System (INIS)

    Located in Victoria British Columbia (BC), Canada, the Portage Creek Bridge is a 124m long, three-span structure with a reinforced concrete piers and abutments on H piles. The bridge was designed prior to the introduction of current bridge seismic design codes and construction practices. Therefore it was not designed to resist the earthquake forces as required by today's standards. The bridge is on a route classified as a Municipal Disaster Route scheduled to be retrofitted to prevent collapse during a design seismic event, with a return period of 475 years (i.e., an event with 105 probability of exceedance in 50 years). Conventional materials and methods were used to retrofit most of the bridge. The dynamic analysis of the bridge predicted the two tall columns of Pier No. 1 will form plastic hinges under an earthquake resulting an additional shear to the short columns of Pier No. 2. A non-liner static pushover analysis indicated the short columns will not be able to form plastic hinges prior to failure in shear. The innovative solution of Fiber Reinforced Polymer wraps (FRPs) was chosen to strengthen the short columns for shear without increasing the moment capacity. The FRP wraps and the bridge were instrumented as one of 36 demonstration projects across Canada sponsored by ISIS (Intelligent Sensing for Innovative Structure) Canada, federally funded Network of Centers of Excellence, to access the performance of FRP and the use of FOS (Fiber Optic Sensors) for Structural Health Monitoring (SHM). The two columns of the bridge pier were strengthened with GFRP (Glass Fiber Reinforced Polymer) wraps with eight bi-directional rosette type strain gauges and four long gauge fiber optic sensors attached to the outer layer of the wraps. In addition, two 3-D Crossbow accelerometers are installed on the pier cap above the columns and a traffic web-cam mounted above the deck at the pier location. The data is collected through high sped internet line to an interactive web page

  17. Research on Selections of Bridge Site and Type of Hutiaoxia Jinsha River Bridge%虎跳峡金沙江大桥方案研究

    Institute of Scientific and Technical Information of China (English)

    刘伟; 陈克坚; 游励晖

    2013-01-01

    Research purposes:The Hutiaoxia Jinsha River Bridge is the key project of Lijiang-Xianggelila Railway and is located in the sensitive environmental and high seismic intensity region with the active fault.The reasonable bridge site and type should be selected for this bridge on consideration of the railway alignment,environment protection,topography,geological condition and the plan of hydraulic engineering on the midstream of the river.Research conclusions:(1)Using the deck type steel braced arch at the No.8 bridge site(416m) of the Hutaioxia Jinsha River Bridge is the best engineering plan.Using the steel truss suspension bridge at No.27 bridge site (98 + 660 +98 m) can remain the condition for the hydroelectric plan of river and can get the better economic and social benefits.(2) The deck type steel braced arch has features of the good load bearing capacity,good rigidity and nice looking and is suitable for the high mountain and deep valley area,but it produces the impact on the water storage and shipping under bridge because the arch rib is installed on bottom of the structure.(3) The steel truss suspension bridge has the features of the fine anti-seismic performance and good rigidity to meet the train requirement.(4) The research result can provide the reference to the type selection of the large span railway bridge in mountain and deep valley area.%研究目的:虎跳峡金沙江大桥为丽香铁路的重点控制性工程.大桥桥址位于环境敏感区、高烈度地震区及断裂发育带,需要综合线路走线、环保、地形、地质情况及金沙江中游水电开发规划的影响,选择虎跳峡金沙江大桥的合理桥位及桥式方案.研究结论:(1)虎跳峡金沙江大桥的8号桥位416 m上承式钢桁拱桥是最优的工程方案,27号桥位(98+660 +98)m钢桁梁悬索桥可以为规划中的水电开发预留条件,整体上经济、社会效应更好;(2)上承式钢桁拱桥承载能力高、刚度大、造型优美,适用于

  18. Art History in Education: Students and Teachers Bridging Artworlds and Lifeworlds.

    Science.gov (United States)

    McKeon, Penny

    1994-01-01

    Examines the work of Jurgen Habermas and Arthur Danto and develops a conceptual structure that views art education as an interpretive and reflective network that bridges school and life experiences. Contends that visual arts contribute to the development of reflective capacities. (CFR)

  19. High energy x-ray radiography and computed tomography of bridge pins

    Energy Technology Data Exchange (ETDEWEB)

    Green, R E; Logan, C M; Martz, H E; Updike, E; Waters, A M

    1999-05-01

    Bridge pins were used in the hanger assemblies for some multi-span steel bridges built prior to the 1980's, and are sometimes considered fracture critical elements of a bridge. During a test on a bridge conducted by the Federal Highway Administration (FHWA), ultrasonic field inspection results indicated that at least two pins contained cracks. Several pins were removed and selected for further examination. This provided an excellent opportunity to learn more about these pins and the application of x-ray systems at Lawrence Livermore National Laboratory (LLNL), as well as to learn more about the application of different detectors recently obtained by LLNL. Digital radiographs and computed tomography (CT) were used to characterize the bridge pins, using a LINAC x-ray source with a 9-MV bremsstrahlung spectrum. We will describe the performance of two different digital radiographic detectors. One is a detector system frequently used at LLNL consisting of a scintillator glass optically coupled to a CCD camera. The other detector is a new amorphous silicon detector recently acquired by LLNL.

  20. parametric modeling and computing of multi-tower suspension bridge based on ANSYS

    Institute of Scientific and Technical Information of China (English)

    Feng Zhaoxiang; Zhao An; Song Jianyong; Yang Yun

    2012-01-01

    Based on FEM (finite element method) program ANSYS and the OpenGL graphics, this paper develops the parametric modeling module and the computing module of the multi-tower suspension bridge, the modules being embedded into the ANSYS system, and the parametric modeling module parameters can be entered by way of interface, which can fast establish a multi-tower suspension bridge model. Calculation module can establish load conditions for the features of road bridge and specifications, in which multiple conditions can be defined and solved automatically. Postprocessing part of the solution also serves the results of the subtotals and selects the output, so that the results of the output and finishing work have become more convenient and easier, and also the results can be saved in word, excel and other different file types.

  1. Bridges and barriers to health: her story - Emirati women's health needs.

    Science.gov (United States)

    Winslow, Wendy Wilkins; Honein, Gladys

    2007-03-01

    Health care services in the United Arab Emirates have developed rapidly in the last 30 years fueled by oil revenues. These services have been planned and provided predominantly by non-nationals, with mixed success. The authors identify aspects of the health care system and the sociocultural environment that create both barriers and bridges to holistic health for Emirati women. Barriers include early/consanguineous marriage, frequent childbearing, polygamy, and care that is lacking in competence and cultural sensitivity. Bridges include Islam, folk medicine, cultural traditions, and the opportunity to travel abroad for health care. Maids are seen as both a barrier and bridge at different times. Recommendations for future improvements include listening to Emirati women and providing more gender-appropriate, holistic, and culturally congruent programs.

  2. Bridge Building and Other Possible Metaphors for Patching over Discrepancies between Typical and Atypical Development

    Science.gov (United States)

    Chandler, Michael

    2016-01-01

    The next several pages are intended as a "Commentary" on the six target articles bundled together as a Special Issue of the "Journal of Cognition and Development"--literature reviews and research reports all intended to "build bridges" between the study of cognitive development in typical and atypical populations.

  3. Organizational and Occupational Commitment in Relation to Bridge Employment and Retirement Intentions

    Science.gov (United States)

    Jones, David A.; McIntosh, Barbara R.

    2010-01-01

    Understanding the antecedents to retirement and bridge employment is important to older-aged adults who seek ways to smoothly transition to full retirement, and to organizations that benefit from retaining their highly skilled and most experienced workers, especially in occupations for which labor shortages are projected. We tested the effects of…

  4. Bridging Literary and Philosophical Genres: Judgement, Reflection and Education in Camus' "The Fall"

    Science.gov (United States)

    Roberts, Peter

    2008-01-01

    Both literature and philosophy, as genres of writing, can enable us to address important ontological, epistemological and ethical questions. One author who makes it possible for readers to bridge these two genres is Albert Camus. Nowhere is this more evident than in Camus' short novel, "The Fall". "The Fall", through the character and words of…

  5. Bridge technology report

    CERN Document Server

    2013-01-01

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

  6. Effect of nonlinearity of restrainer and supports on the elasto-plastic seismic response of continuous girder bridge

    Directory of Open Access Journals (Sweden)

    Wang Changfeng

    2014-10-01

    Full Text Available During an earthquake, the nonlinearity of the bridge structure mainly occurs at the supports, bridge piers and restrainers. When entering nonlinear stage, members of the bridge structure affect the elasto-plastic seismic response of the whole structure to a certain extent; for multi-span continuous bridges, longitudinal restrainers can be installed on the movable piers to optimise the distribution of seismic force and enable the movable piers to bear a certain amount of seismic effect. In order to evaluate the effect of nonlinearity of restrainer and supports on the elasto-plastic seismic response of continuous girder bridge, analytical models of continuous girder bridge structure considering the nonlinearity of movable supports, restrainers and bridge piers were built and the nonlinear time history analysis was conducted to evaluate the effect of nonlinearity of restraining devices and supports on the elasto-plastic seismic response of continuous girder bridge. Relevant structural measures and recommendation were made to reduce the seismic response of the fixed piers of the continuous girder bridge.

  7. Experimental Study on Shear Lag Effect of Partial Cable-Stayed Bridge and Elasto-Plastic Seismic Analysis

    Institute of Scientific and Technical Information of China (English)

    WU Gao-feng; XU Hong; CHEN Xing-chong

    2005-01-01

    The project of Xiaoxihu Yellow River Bridge in Lanzhou is chosen as partial cable-stayed bridge. To get the shear lag effect and anti-earthquake performance of the actual bridge under various loading conditions, organic glass scaled model was adopted to have an experiment and a theory research at one time. The experiment result is the basically same as the theory calculation which proves the FEA method can well calculate shear lag effect and dynamical performance. As a result, because the bridge is located in a seismic area of 8 degree, an elasto-plastic seismic checking is performed by customized FEA program in this paper.

  8. National Bridge Inventory (NBI) Bridges

    Data.gov (United States)

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

  9. Sustainable Bridges – A European Integrated Research Project – Background Overview and Results

    DEFF Research Database (Denmark)

    Täljsten, Björn; Elfgren, Lennart

    2008-01-01

    of energy and release of greenhouse gases. To help our society to be more sustainable, it is important to retain and use what we already have where possible, rather than investing in new structures. Instead of tearing down old, often beautiful, railway bridges and replacing them with new ones, we need...... to preserve and upgrade them by using better assessment, monitoring and strengthening methods. This was also the aim of the European Integrated Research Project “Sustainable Bridges – Assessment for Future Traffic Demands and Longer Lives” when it was accepted for funding by the European Commission in 2003....... The project established the following three specific goals: 1. increase the transport capacity of existing railway bridges by allowing higher axle loads (up to 33 tons) for freight traffic at moderate speeds or by allowing higher speeds (up to 350 km/hour) for passenger traffic with low axle loads 2. extend...

  10. Assessing and updating the reliability of concrete bridges subjected to spatial deterioration - principles and software implementation

    DEFF Research Database (Denmark)

    Schneider, Ronald; Fischer, Johannes; Bügler, Maximilian;

    2015-01-01

    to implement the method presented here. The software prototype is applied to a typical highway bridge and the influence of inspection information on the system deterioration state and the structural reliability is quantified taking into account the spatial correlation of the corrosion process. This work...

  11. Structure and dynamics of a salt-bridge model system in water and DMSO.

    Science.gov (United States)

    Lotze, S; Bakker, H J

    2015-06-01

    We study the interaction between the ions methylguanidinium and trifluoroacetate dissolved in D2O and dimethylsulfoxide with linear infrared spectroscopy and femtosecond two-dimensional infrared spectroscopy. These ions constitute model systems for the side chains of arginine and glutamic and aspartic acid that are known to form salt bridges in proteins. We find that the salt-bridge formation of methylguanidinium and trifluoroacetate leads to a significant acceleration of the vibrational relaxation dynamics of the antisymmetric COO stretching vibration of the carboxyl moiety of trifluoroacetate. Salt-bridge formation has little effect on the rate of the spectral fluctuations of the CN stretching vibrations of methylguanidinium. The anisotropy of the cross peaks between the antisymmetric COO stretching vibration of trifluoroacetate and the CN stretching vibrations of methylguanidinium reveals that the salt-bridge is preferentially formed in a bidentate end-on configuration in which the two C=O groups of the carboxylate moiety form strong hydrogen bonds with the two -NH2 groups of methylguanidinium.

  12. Fabrication and parameters calculation of room temperature terahertz detector with micro-bridge structure

    Science.gov (United States)

    Wang, Jun; Li, Weizhi; Gou, Jun; Wu, Zhiming; Jiang, Yadong

    2015-01-01

    Room temperature terahertz (THz) detector indicates great potentials in imaging application because of real-time, compact bulk and unique spectral characteristics. Different dimension THz detectors based on micro-bridge structure were designed and simulated to get optimizing microbolometer parameters from the simulation results of membrane temperature changing and THz absorption. Those microbolometers were fabricated with complex semiconductor process and three dimension deformations of micro-bridges were obtained by laser scanning confocal microscope to identify the focal plane array micro-bridge design. The noise equivalent power of THz detector achieves 123 pW/Hz1/2 and average response time of the detector is 6.7 ms, which is suitable for the application of active THz imaging.

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

    Institute of Scientific and Technical Information of China (English)

    Li Jianzhong; Peng Tianbo; Xu yan

    2008-01-01

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

  14. Push-pull flexibly-bridged bis(haloBODIPYs): solvent and spacer switchable red emission.

    Science.gov (United States)

    Ray, César; Bañuelos, Jorge; Arbeloa, Teresa; Maroto, Beatriz L; Moreno, Florencio; Agarrabeitia, Antonia R; Ortiz, María J; López-Arbeloa, Iñigo; de la Moya, Santiago

    2016-08-01

    A series of uncommon bis(BODIPYs), involving a flexible bridge linking the BODIPY α-positions and key functionalities to efficiently give an electronic push-pull effect, has been synthesized, as well as photophysically and structurally studied. It is demonstrated that the designed push-pull effect efficiently enables intramolecular charge transfer (ICT) processes upon photoexcitation, with the generated low-lying ICT state being the main deactivation channel from the locally excited state and, hence, ruling the fluorescence response. Noticeably, this response is modulated by the solvent polarity, and also by the bridge structure. Regarding this, BINOL- and BINAM-based bridges are found to promote an interesting unprecedented solvent-switchable dual emission from the ICT state with high Stokes shifts, triggering a significant bright red emission in less polar media. PMID:27378499

  15. HOMO- AND COPOLYMERIZATION OF ETHYLENE CATALYZED BY ANSA-METALLOCENES WITH DOUBLY HETERO-BRIDGES

    Institute of Scientific and Technical Information of China (English)

    Min Yang; Wei-dong Yan; Xiao-li Shen; Bin Mu; Bai-quan Wang

    2008-01-01

    Three ansa-metallocenes (Me2C)(Me2Si)Cp2TiCl2 (1), [(CH2)5C](Me2Si)Cp2TiCl2 (2) and (Me2C)(Me2Si)Cp2ZrCl2 (3) with larger dihedral angles and longer distance from metal to the center of Cp planes were synthesized and used as catalysts for ethylene polymerization in the presence of methylaluminoxane (MAO). In the case of ethylene polymerization, compared the feature structures of unbridged metallocenes,singly bridged metallocenes and doubly bridged metallocenes 1, 2, 3, there exhibit the relationship between structural characteristics and the catalytic properties with behavior of polymers. And the view that the dimensions of the short dimethylsilylene and isopropylidene bridges of metallocene 3 do not match the co-ordination requirement of the larger zirconium atom can also explain the result for ethylene polymerization. Catalyzed by complexes 1 and 2 respectively, the copolymerizations of ethylene with 1-hexene, 1-octene,especially the long chain α-olefins (1-tetradecene,1-hexadecene) were investigated, and showed high incorporations and comonomer effects in almost all the examples. The melting points of the copolymers are approximately 4%-31% below those of the homopolymers, and the enthalpies of fusion decrease greatly due to the lower crystallinity. The microstructures of the copolymer were analyzed with 13C-NMR to determine the comonomer sequence distributions and number-average sequence lengths. Comparison between results for the complexes 1 and 2 with different bridging groups respectively showed that the nature of the bridge has a significant effect on both the incorporation and sequence distribution of the α-olefin. Because of the bridges in ansa-metallocene complexes, the copolymerization behavior was different in using catalyst I and catalyst 2.

  16. Construction and Design of Post-Tensioned Pearl-Chain Bridges using SL-Technology

    DEFF Research Database (Denmark)

    Halding, Philip Skov

    2016-01-01

    a filling layer of lower stiffness above the arches to level the road surface. The present Ph.D. thesis is part of a larger development project about Pearl‐Chain Bridges funded by Innovationsfonden. The project also included another Ph.D. study about the developed materials used in Pearl‐Chain Bridges......, and numerical modelling. Despite of high levels of normal force in PC‐Bridges, the result showed that a Mesnager inspired hinge type had a response similar to what was predicted in the literature. A specially designed saddle bearing also had elastic and plastic rotational resistance, but this hinge type......) A test to fracture to observe the ductility in the system, and fracture type. The collapse occurred after two plastic hinges were formed in the 3/8, and 5/8 points of the span. Several warnings signs were observed when approaching the maximum loading....

  17. Reinforcement and numerical analysis on the corbel of a half-through arch bridge

    Institute of Scientific and Technical Information of China (English)

    LIAO Bi-hai; WANG Yuan-han; CHENG Hong-guang; MIAO Yu

    2009-01-01

    Corbels support the crossbeams of half-through arch bridges. They are prone to cracking easily due to their characteristics and complicated loading conditions. Based on a practical diagnosis of a bridge crossbeam, we bonded steel plates onto bridge corbels to strengthen them. We carried out a numerical analysis on the effectiveness of the reinforcement by using the commercial software ANSYS. The numerical analysis shows that the stresses near the section break increased slightly, but the variation amplitude was small and all the stresses were within an allowable range. The loading test indicates that it is feasible to strengthen the corbel with vertical bonded steel plates. Therefore, the reinforcement is effective and economical. This reinforcement method is suitable for this type of corbel and can be applied in similar cases.

  18. A Highly Accurate and Efficient Analytical Approach to Bridge Deck Free Vibration Analysis

    Directory of Open Access Journals (Sweden)

    D.J. Gorman

    2000-01-01

    Full Text Available The superposition method is employed to obtain an accurate analytical type solution for the free vibration frequencies and mode shapes of multi-span bridge decks. Free edge conditions are imposed on the long edges running in the direction of the deck. Inter-span support is of the simple (knife-edge type. The analysis is valid regardless of the number of spans or their individual lengths. Exact agreement is found when computed results are compared with known eigenvalues for bridge decks with all spans of equal length. Mode shapes and eigenvalues are presented for typical bridge decks of three and four span lengths. In each case torsional and non-torsional modes are studied.

  19. CURRENT PERSPECTIVES OF POTTER'S GLOBAL BIOETHICS AS A BRIDGE BETWEEN CLINICAL (PERSONALIZED) AND PUBLIC HEALTH ETHICS.

    Science.gov (United States)

    Turina, Iva Sorta-Bilajac; Brkljacić, Morana; Grgas-Bile, Cecilija; Gajski, Domagoj; Racz, Aleksandar; Cengić, Tomislav

    2015-12-01

    In the context of modern scientific and technological developments in biomedicine and health care, and the potential consequences of their application on humans and the environment, Potter's global bioethics concept resurfaces. By actualizing Potter's original thoughts on individual bioethical issues, the universality of two of his books, which today represent the backbone of the world bioethical literature, "Bioethics--Bridge to the Future" and "Global Bioethics: Building on the Leopold Legacy", is emphasized. Potter's global bioethics today can legitimately be viewed as a bridge between clinical personalized ethics on the one hand and ethics of public health on the other.

  20. Dynamic Bridge Response for a Bridge-friendly Truck

    Directory of Open Access Journals (Sweden)

    V. Šmilauer

    2004-01-01

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

  1. To the problem of cross-bridge tension in steady muscle shortening and lengthening

    CERN Document Server

    Kokshenev, Valery B

    2009-01-01

    Despite the great success of the Huxley sliding filament model proposed half a century ago for actin-myosin linkages (cross-bridges), it fails to explain the force-velocity behavior of stretching skeletal muscles. Huxley's two-state kinetic equation for cross-bridge proportions is therefore reconsidered and a new solution to the problem of steady muscle eccentric and concentric contractions is reported. When the second law of statistical thermodynamics is applied to cross-bridge proportions, the weakly bound states appear to be correlated to the strongly bound states via structural and kinetic intrinsic muscle characteristics. The explicit force-velocity curve fits the empirical tension-velocity data on frog muscle shortening using only one adjustable parameter, while the Huxley model employed four parameters.

  2. A New Uniform Phase Bridge Functional: Test and Its Application to Non-uniform Phase Fluid

    Institute of Scientific and Technical Information of China (English)

    ZHOU Shi-Qi; CHEN Hong; ZHANG Xiao-Qi

    2003-01-01

    A new bridge functional as a function of indirect correlation function was proposed, which was basedon analysis on the asymptotic behavior of the Ornstein-Zernike (OZ) equation system and a series expansion whoserenormalization resulted in an adjustable parameter determined by the thermodynamics consistency condition. Theproposed bridge functional was tested by applying it to bulk hard sphere and hard core Yukawa fluid for the predictionof structure and thermodynamics properties based on the OZ equation. As an application, the present bridge functionalwas employed for non-uniform fluid of the above two kinds by means of the density functional theory methodology, theresulting density distribution profiles were in good agreement with the available computer simulation data.

  3. Enhanced extraordinary optical transmission (EOT) through arrays of bridged nanohole pairs and their sensing applications

    KAUST Repository

    Yue, Weisheng

    2014-01-01

    Extraordinary optical transmission (EOT) through arrays of gold nanoholes was studied with light across the visible to the near-infrared spectrum. The EOT effect was found to be improved by bridging pairs of nanoholes due to the concentration of the electromagnetic field in the slit between the holes. The geometrical shape and separation of the holes in these pairs of nanoholes affected the intensity of the transmission and the wavelength of resonance. Changing the geometrical shapes of these nanohole pairs from triangles to circles to squares leads to increased transmission intensity as well as red-shifting resonance wavelengths. The performance of bridged nanohole pairs as a plasmonic sensor was investigated. The bridged nanohole pairs were able to distinguish methanol, olive oil and microscope immersion oil for the different surface plasmon resonance in transmission spectra. Numerical simulation results were in agreement with experimental observations. © 2014 the Partner Organisations.

  4. CAMPARE and Cal-Bridge: Two Institutional Networks Increasing Diversity in Astronomy

    Science.gov (United States)

    Rudolph, Alexander L.; Impey, Chris David; Smecker-Hane, Tammy A.

    2016-01-01

    We describe two programs, CAMPARE and Cal-Bridge, with the common mission of increasing participation of groups traditionally underrepresented in astronomy, through summer research opportunities, in the case of CAMPARE, scholarships in the case of Cal-Bridge, and significant mentoring in both programs, leading to an increase in their numbers successfully pursuing a PhD in the field.In 6 years, the CAMPARE program has sent 62 students, >85% from underrepresented groups, to conduct summer research at one of twelve major research institutions in California, Arizona, and Wyoming. The graduation rate among CAMPARE scholars is 97%, and of the 37 CAMPARE scholars who have graduated with a Bachelor's degree, almost 60% (21) have completed or are pursuing graduate education in astronomy or a related field, at institutions including UCLA, USC, UC Riverside, Stanford, Univ. of Rochester, Georgia Tech, Kent State, Indiana Univ., Univ. of Oregon, Syracuse, and the Fisk-Vanderbilt Master's-to-PhD program. The Cal-Bridge program is a CSU-UC Bridge program comprised of faculty form 5 University of California (UC), 8 California State University (CSU), and 8 California Community College (CCC) campuses in Southern California. Cal-Bridge provides much deeper mentoring and professional development experiences over the last two years of undergraduate and first year of graduate school to students from this diverse network of higher education institutions. Cal-Bridge Scholars benefit from financial support, intensive, joint mentoring by CSU and UC faculty, professional development workshops, and exposure to research opportunities at the participating UC campuses.

  5. Finite Element and Experimental Analysis and Evaluation of Static and Dynamic Responses of Oblique Pre-stressed Concrete Box Girder Bridge

    Directory of Open Access Journals (Sweden)

    Ali Fadhil Naser

    2013-10-01

    Full Text Available Hashuang bridge is type of prestressed concrete box girder oblique bridge and it is located in Harbin City within Heilongjiang province in the east north of China. The objectives of this study are to investigate the appearance of the bridge structure and identify all the damages in the bridge structural members and to evaluate the structural performance of the bridge structure under dead and live loads. Finite element analysis is used to analyze the static designed internal forces and dynamic responses by adopting SAP200 software Ver. 14.2.0. Static and dynamic load test are adopted to evaluate the structural performance of the bridge structure. The results of field investigation process of the bridge appearance show that the bridge suffers from serious damages. The web of box girder of the second span near pier No.2 (in the quarter of middle span at 39m on the bridge length suffers from serious shear cracks. The state of abutments, piers and sidewalks is good, but the bearing, drainage holes, steel rail and expansion joints are not good and they suffer from much damage. The steel rail is corroded and the expansion joint loses the material which fills the joint. There are many dusts and debris is collected on the bridge deck in the location near sidewalk. The analysis results of finite element and load tests show that there are high tensile stresses in the quarter of middle span at distance 39 m of the bridge length and the state of the bridge structure is not good and the main problem of the bridge structure in the original design of prestressed tendons. Therefore, this study recommends for repairing and strengthening the bridge structure to increase the stiffness and strength and to improve the bearing capacity of the bridge structural members to increase the service live of the bridge structure.

  6. Damage analysis and seismic retrofitting of a continuous prestressed reinforced concrete bridge

    Directory of Open Access Journals (Sweden)

    Nicola Caterino

    2014-12-01

    Full Text Available The seismic analysis and retrofit of prestressed reinforced concrete bridge is discussed by considering a real case of a viaduct still in use. The unique features of this bridge make this type of bridge particularly interesting, either structurally or architecturally. The paper begins with the analysis of certain particular structural deficiencies that emerged during the viaduct operation. The results of the analysis indicate that the structural performance can be enhanced by only modifying the support devices. The primary structural components are not required to be involved in the retrofitting process. Using the modern seismic code, the upgrading of the viaduct performance is obtained by replacing the old bearing devices on the piers and existing viscous dampers connected abutments to the deck with new modernised ones.

  7. Repair and Strengthening Assessment of Existing Bridges Based on Time-Dependent Reliability Analysis

    Institute of Scientific and Technical Information of China (English)

    孙晓燕; 黄承逵; 孙保沭

    2004-01-01

    The strategy on repair and strengthening of existing bridges based on time-dependent reliability was analyzed with the maximum expected benefit as the objective function. A sample of risk-ranking decision was illustrated based on updated inspection information with 35 survival age. The effect of improvement of live loads and difference of repair methods on time-dependent reliability of existing bridges are considered. The results show that the decision method can be used in real project, with the cost of failure consequence and the risk of failure considered.

  8. Simple bridge detector for use with a low-temperature capacitance thermometer, and thermometer performance limits.

    Science.gov (United States)

    Prober, D E

    1979-03-01

    A simple high-resolution bridge circuit for use with a glass-ceramic capacitance thermometer is described. This circuit allows a linear readout of capacitance changes and has better than 1 mK resolution and short-term stability. Performance limits of the thermometer itself are also reported. Irreproducibility of thermometer calibration upon thermal cycling can be as large as 0.3 K, and changes in the calibration slope dC/dT are also observed. The bridge circuit described partially compensates for these shifts in dC/dT. PMID:18699517

  9. Bridged Race Population Estimates

    Data.gov (United States)

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

  10. Synthesis and spectral and redox properties of three triply bridged complexes of ruthenium

    Science.gov (United States)

    Llobet, A.; Curry, M.E.; Evans, H.T.; Meyer, T.J.

    1989-01-01

    Syntheses are described for the ligand-bridged complexes [(tpm)RuIII(??-O)(??-L)2RuIII(tpm) n+ (L = O2P(O)(OH), n = 0 (1); L = O2CO, n = 0 (2); L = O2CCH3, n = 2 (3); tpm is the tridentate, facial ligand tris(1-pyrazolyl)methane. The X-ray crystal structure of [(tpm)Ru(??-O)(??-O2P(O)(OH))2Ru(tpm)]??8H 2O was determined from three-dimensional X-ray counter data. The complex crystallizes in the trigonal space group P3221 with three molecules in a cell of dimensions a = 18.759 (4) A?? and c = 9.970 (6) A??. The structure was refined to a weighted R factor of 0.042 based on 1480 independent reflections with I ??? 3??(I). The structure reveals that the complex consists of two six-coordinate ruthenium atoms that are joined by a ??-oxo bridge (rRU-O = 1.87 A??; ???RuORu = 124.6??) and two ??-hydrogen phosphato bridges (average rRu-O = 2.07 A??) which are capped by two tpm ligands. The results of cyclic voltammetric and coulometric experiments show that the complexes undergo both oxidative and reductive processes in solution. Upon reduction, the ligand-bridged structure is lost and the monomer [(tpm)Ru(H2O)3]2+ appears quantitatively. All three complexes are diamagnetic in solution. The diamagnetism is a consequence of strong electronic coupling between the low-spin d5 Ru(III) metal ions through the oxo bridge and the relatively small Ru-O-Ru angle. ?? 1989 American Chemical Society.

  11. Crack mitigation in concrete bridge decks through experimental analysis and computer modeling

    Science.gov (United States)

    Richardson, Douglas M.

    Bridge deck cracking can cause deterioration of bridge decks, leading to a shorter life span and poor performance. Throughout the US, cracking has been identified as a problem, with transverse cracking along the deck at regular spacings being the most prominent type. This problem is usually caused by drying shrinkage within the concrete. The material properties, restraint, and distances without expansion joints all affect the crack pattern within the deck. This study will delve into the reasons that bridge decks crack, the strains that are associated with drying shrinkage, and possible methods for abating its effects. The research is divided into two parts, the first being laboratory experimentation, which was conducted through the use of two 7 ft. x 10 ft. experimental concrete bridge bays. Each bay was instrumented with strain and temperature gages throughout the deck and girders, which collected data for six months. The first deck was poured with a control concrete mix used currently in Illinois. The second deck was poured with a type K expansive concrete, which could battle the effects of shrinkage. For both decks, the results suggest a compressive strain throughout the rebar and along the top surface of the concrete, except for the locations where cracks are found (at these locations the strain slopes upward into tension). The strain in the type K deck, though, was notably less than that in the control deck and the onset of cracking was delayed by three weeks, giving the indication of an improvement over the current mix design. The second portion of the research was focused on using a finite element model to replicate the bridge bay and study the results. Equivalent temperature loading was used to apply the shrinkage loads recorded during the experimental portion of the research. The model was then expanded to encompass a full-scale bridge and in order to provide some insight into shrinkage strain in the real world. The end goal is to help alleviate cracking

  12. Hydrographic surveys of the Missouri and Yellowstone Rivers at selected bridges and through Bismarck, North Dakota, during the 2011 flood

    Science.gov (United States)

    Densmore, Brenda K.; Strauch, Kellan R.; Dietsch, Benjamin J.

    2013-01-01

    The U.S. Geological Survey (USGS), in cooperation with the North Dakota Department of Transportation and the North Dakota State Water Commission, completed hydrographic surveys at six Missouri River bridges and one Yellowstone River bridge during the 2011 flood of the Missouri River system. Bridges surveyed are located near the cities of Cartwright, Buford, Williston, Washburn, and Bismarck, N. Dak. The river in the vicinity of the bridges and the channel through the city of Bismarck, N. Dak., were surveyed. The hydrographic surveys were conducted using a high-resolution multibeam echosounder (MBES), the RESON SeaBatTM 7125, during June 6–9 and June 28–July 9, 2011. The surveyed area at each bridge site extended 820 feet upstream from the bridge to 820 feet downstream from the bridge. The surveyed reach through Bismarck consisted of 18 miles of the main channel wherever depth was sufficient. Results from these emergency surveys aided the North Dakota Department of Transportation in evaluating the structural integrity of the bridges during high-flow conditions. In addition, the sustained high flows made feasible the surveying of a large section of the normally shallow channel with the MBES. In general, results from sequential bridge surveys showed that as discharge increased between the first and second surveys at a given site, there was a general trend of channel scour. Locally, complex responses of scour in some areas and deposition in other areas of the channel were identified. Similarly, scour around bridge piers also showed complex responses to the increase in flow between the two surveys. Results for the survey area of the river channel through Bismarck show that, in general, scour occurred around river structures or where the river has tight bends and channel narrowing. The data collected during the surveys are provided electronically in two different file formats: comma delimited text and CARIS Spatial ArchiveTM (CSARTM) format.

  13. Structural and functional characterization of the conserved salt bridge in mammalian paneth cell alpha-defensins

    DEFF Research Database (Denmark)

    Rosengren, K Johan; Daly, Norelle L; Fornander, Liselotte M;

    2006-01-01

    )-Crp4 peptide, in which a conserved Glu(15) residue was replaced by Asp. Structural analysis of the two peptides confirms the involvement of this Glu in a conserved salt bridge that is removed in the mutant because of the shortened side chain. Despite disruption of this structural feature, the peptide...... variant retains a well defined native fold because of a rearrangement of side chains, which result in compensating favorable interactions. Furthermore, salt bridge-deficient Crp4 mutants were tested for bactericidal effects and resistance to proteolytic degradation, and all of the variants had similar...

  14. Seismic evaluation of K basin bridge cranes (HOI-320 ampersand HOI-418) and supporting structure

    International Nuclear Information System (INIS)

    The Safety Class 1 100-K fuel storage basins are vulnerable to impact damage if a bridge crane were to fall during a seismic event. The pupose of this report is to address the adequacy of the K Basin bridge cranes to resist a seismic-induced fall. The approach used to demonstrate adequacy against falling, was to evaluate the crane structural components relative to requirements specified in ASME NOG-1, Rules for Construction of Overhead and Gantry Cranes. Additionally, wheel lift-off and the adequacy of the crane supporting structure, are addressed. Seismic adequacy of the mechanical hoist equipment is not addressed in this report

  15. Determine of velocity field with PIV and CFD during the flow around of bridge piers

    Directory of Open Access Journals (Sweden)

    Picka D.

    2013-04-01

    Full Text Available The article describes the processing of specific junior research FAST-J-11-51/1456 which dealt with physical and CFD of the velocity field during the flow around of bridge piers. Physical modelling has been carried out in Laboratory of water management research in Institute of Water Structures in Brno University of Technology – Faculty of Civil Engineering. To measure of the velocity field in profile of bridge piers were used laser measuring method PIV (Particle Image Velocimetry. The results of PIV served as a basis for comparing experimental data with CFD results of this type of flow in the commercial software ANSYS CFX.

  16. 保定下车亭分水口门涵洞预留橡胶止水带修复%Baoding Xiacheting bleeder culvert reserved rubber waterstop patching solution analysis

    Institute of Scientific and Technical Information of China (English)

    王利平; 张广扬

    2015-01-01

    通过对南水北调保定下车亭分水口门涵洞预留橡胶止水带不同修补方案的比选分析,提出了3种修补方案及具体施工工艺,总结出各方案的优缺点及具体的适用条件,为今后的相关工程问题提供借鉴。%Through the analysis and comparison of the South-to-North Water Diversion Baoding Xiacheting bleeder culvert reserved rubber waterstop patching solutions,put forward three kinds of repair plan and specific const-ruction technology, summarizes the advantages and disadvantages of each scheme and the applicable conditions,provide reference for future related engineering problem.

  17. Drainage Structure Datasets and Effects on LiDAR-Derived Surface Flow Modeling

    Directory of Open Access Journals (Sweden)

    Ruopu Li

    2013-12-01

    Full Text Available With extraordinary resolution and accuracy, Light Detection and Ranging (LiDAR-derived digital elevation models (DEMs have been increasingly used for watershed analyses and modeling by hydrologists, planners and engineers. Such high-accuracy DEMs have demonstrated their effectiveness in delineating watershed and drainage patterns at fine scales in low-relief terrains. However, these high-resolution datasets are usually only available as topographic DEMs rather than hydrologic DEMs, presenting greater land roughness that can affect natural flow accumulation. Specifically, locations of drainage structures such as road culverts and bridges were simulated as barriers to the passage of drainage. This paper proposed a geospatial method for producing LiDAR-derived hydrologic DEMs, which incorporates data collection of drainage structures (i.e., culverts and bridges, data preprocessing and burning of the drainage structures into DEMs. A case study of GIS-based watershed modeling in South Central Nebraska showed improved simulated surface water derivatives after the drainage structures were burned into the LiDAR-derived topographic DEMs. The paper culminates in a proposal and discussion of establishing a national or statewide drainage structure dataset.

  18. D4.2 Guideline for Load and Resistance Assessment of Existing European Railway Bridges - Sustainable Bridges - Assessment for future traffic demands and longer lives

    OpenAIRE

    EUROPEAN COMMISSION

    2007-01-01

    The bridge assessment in many aspects is very similar to the bridge design. The same basic principles lie at the heart of the process. Nevertheless, an important difference lies in the fact when a bridge is being designed, an element of conservatism is generally a good thing that can be achieved with very little additional costs. When a bridge is being assessed, it is important to avoid unnecessarily conservative measures because of the financial implications that may follow the decision of r...

  19. Force Field Analysis: A Bridge Between Diagnostic Data and Operational Prescriptions.

    Science.gov (United States)

    Wiener, William K.

    The technique of force field analysis represents a method for bridging the gap between diagnostic data and learning prescriptions and objectives. Through the use of this technique the teacher is able to delineate the strengths and weaknesses of the individual and to generate strategies for meeting specific objectives. A force field refers to a…

  20. Modal analysis of a concrete highway bridge: Structural calculations and vibration-based results

    NARCIS (Netherlands)

    Miao, S.; Veerman, R.P.; Koenders, E.A.B.; Knobbe, A.

    2013-01-01

    In the field of civil infrastructure, Structural Health Monitoring systems are implemented more and more frequently with the aim to safeguard the safety and service-life of structures such as bridges and tunnels. Changes in the integrity of the material and/or structural properties of this class of

  1. Facebook Use and Social Capital: To Bond, To Bridge, or to Escape

    Science.gov (United States)

    Kwon, Min-Woo; D'Angelo, Jonathan; McLeod, Douglas M.

    2013-01-01

    This study employs the uses and gratification approach to investigate how different forms of Facebook use are linked to bridging social capital and bonding social capital. A survey of 152 college students was conducted to address research questions and to test hypotheses. Factor analysis identified six unique uses and gratifications: (a)…

  2. It Began with Hypatia and Ada: Helping Girls Bridge the Technology Gender Gap.

    Science.gov (United States)

    Barron, Daniel D.

    1996-01-01

    Examines causes of female negativity towards technology and presents ways to improve female attitudes and increase involvement in technology education. Discusses the bridging of the gender gap to allow females and males to achieve equality in technology fields. Describes online resources, television programs, and groups that promote female…

  3. An Expert System for Concrete Bridge Management

    DEFF Research Database (Denmark)

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

    1997-01-01

    The importance of bridge repair versus new bridge construction has risen in recent decades due to high deterioration rates that have been observed in these structures. Budgets both for building new bridges and keeping the existing ones are always limited. To help rational decision-making, bridge...

  4. Bridging East and West : The Establishment of the International Institute for Applied Systems Analysis (IIASA) in the United States Foreign Policy of Bridge Building, 1964-1972.

    OpenAIRE

    Riska-Campbell, Leena

    2011-01-01

    The dissertation examines the foreign policies of the United States through the prism of science and technology. In the focal point of scrutiny is the policy establishing the International Institute for Applied Systems Analysis (IIASA) and the development of the multilateral part of bridge building in American foreign policy during the 1960s and early 1970s. After a long and arduous negotiation process, the institute was finally established by twelve national member organizations from the fol...

  5. Embedded Electromechanical Impedance and Strain Sensors for Health Monitoring of a Concrete Bridge

    Directory of Open Access Journals (Sweden)

    Dansheng Wang

    2015-01-01

    Full Text Available Piezoelectric lead zirconate titanate (PZT is one of the piezoelectric smart materials, which has direct and converse piezoelectric effects and can serve as an active electromechanical impedance (EMI sensor. The design and fabrication processes of EMI sensors embedded into concrete structures are presented briefly. Subsequently, finite element modeling and modal analysis of a continuous rigid frame bridge are implemented by using ANSYS and MIDAS and validated by the field test results. Uppermost, a health monitoring technique by employing the embedded EMI and strain sensors is proposed in this paper. The technique is not based on any physical model and is sensitive to incipient structural changes for its high frequency characteristics. A practical study on health monitoring of the continuous rigid frame bridge is implemented based on the EMI and strain signatures. In this study, some EMI and strain sensors are embedded into the box-sectional girders. The electrical admittances of distributed EMI active sensors and the strains of concrete are measured when the bridge is under construction or in operation. Based on the electrical admittance and strain measurements, the health statuses of the continuous rigid frame bridge are monitored and evaluated successfully in the construction and operation stages using a root-mean-square deviation (RMSD index.

  6. Mechanism and Dynamics of Charge Transfer in Donor-Bridge-Acceptor Systems

    NARCIS (Netherlands)

    Gorczak-Vos, N.

    2016-01-01

    Photoinduced charge transfer in organic materials is a fundamental process in various biological and technological areas. Donor-bridge-acceptor (DBA) molecules are used as model systems in numerous theoretical and experimental work to systematically study and unravel the underlying mechanisms of cha

  7. Bridging the Gap between Academic Research and Regional Development in the Basque Country

    Science.gov (United States)

    Karlsen, James; Larrea, Miren; Wilson, James R.; Aranguren, Mari Jose

    2012-01-01

    The discussion in this article focuses on how the gap between academic knowledge and regional development can be bridged, creating conditions for change processes between researchers and regional agents. Institutional entrepreneurs can create regional development organisations and research organisations, but in order to fulfil regional needs it is…

  8. Measurements and analysis of vibrations at Virilla Bridge, national route N° 1

    Directory of Open Access Journals (Sweden)

    Francisco Navarro-Henríquez

    2015-06-01

    The measurements allowed quantifying the vibration magnitudes and deformation in various sections of the bridge, on condition of vehicular traffic service (environmental performance. The experimental results are compared with computational analytical modeling of the structure and also with national and international standards.

  9. Effects of bridge exercises with a sling and vibrations on abdominal muscle thickness in healthy adults.

    Science.gov (United States)

    Gong, Won-tae

    2015-01-01

    In the present study, we aimed to examine the changes in the thickness of the transversus abdominis (TrA) and internal oblique (Io) muscles using ultrasonography in adults who performed bridge exercises with the abdominal drawing-in maneuver and a sling and received micro vibrations. In total, 32 subjects were divided into a therapy (n= 16) and control (n= 16) groups. The therapy group completed nine sets, with four repetitions, of bridge exercises with the sling and received vibrations. The control group completed nine sets, with four repetitions, of bridge exercises with the sling and did not receive vibrations. The thicknesses of the TrA and Io muscles were measured in both groups using ultrasonography before and after therapy. According to the pressure applied to the biofeedback unit, both groups showed significant changes in the thicknesses of the TrA and Io muscles after therapy (P 0.05). These findings indicate that approximately 15 minutes of vibrations during bridge exercises on unstable surfaces with a sling facilitates the activation of the deep trunk muscles and further enhances the activation of the TrA.

  10. Development of bridge-scour instrumentation for inspection and maintenance personnel

    Science.gov (United States)

    Mueller, David S.; Landers, Mark N.; ,

    1993-01-01

    Inspecting bridges and monitoring scour during high flow can improve public transportation safety by providing early identification of scour and stream stability problems at bridges. Most bridge-inspection data are collected during low flow, when scour holes may have refilled. More than 25 percent of the States that responded to a questionnaire identified lack of adequate methodology and/or equipment as reasons for not collecting scour data during high-flow conditions. Therefore, the U.S. Geological Survey (USGS), in cooperation with the Federal Highway Administration, has begun to develop instrumentation for measuring scour that could be used by inspection and maintenance personnel during high-flow conditions. A variety of instruments and techniques for measuring scour were tested and evaluated in real-time bridge-scour data-collection studies by the USGS. In the National Scour study, fathometers were found to be superior to sounding weights and will be the primary bed-measuring instrument. The ability of low-cost fathometers and fish finders to locate the bed accurately is being evaluated. Simple and efficient methods for deploying the transducer during floods are also important for a successful measurement. The information and additional testing are being used to design new, portable scour-measuring systems.

  11. Sea Ice Thickness, Freeboard, and Snow Depth products from Operation IceBridge Airborne Data

    Science.gov (United States)

    Kurtz, N. T.; Farrell, S. L.; Studinger, M.; Galin, N.; Harbeck, J. P.; Lindsay, R.; Onana, V. D.; Panzer, B.; Sonntag, J. G.

    2013-01-01

    The study of sea ice using airborne remote sensing platforms provides unique capabilities to measure a wide variety of sea ice properties. These measurements are useful for a variety of topics including model evaluation and improvement, assessment of satellite retrievals, and incorporation into climate data records for analysis of interannual variability and long-term trends in sea ice properties. In this paper we describe methods for the retrieval of sea ice thickness, freeboard, and snow depth using data from a multisensor suite of instruments on NASA's Operation IceBridge airborne campaign. We assess the consistency of the results through comparison with independent data sets that demonstrate that the IceBridge products are capable of providing a reliable record of snow depth and sea ice thickness. We explore the impact of inter-campaign instrument changes and associated algorithm adaptations as well as the applicability of the adapted algorithms to the ongoing IceBridge mission. The uncertainties associated with the retrieval methods are determined and placed in the context of their impact on the retrieved sea ice thickness. Lastly, we present results for the 2009 and 2010 IceBridge campaigns, which are currently available in product form via the National Snow and Ice Data Center

  12. 乌苏大桥主桥上部结构设计与计算%Design and Calculation of Superstructure of Main Bridge of Wusu Bridge

    Institute of Scientific and Technical Information of China (English)

    康晋; 肖海珠; 徐伟

    2011-01-01

    The main bridge of the Wusu Bridge is a single pylon and single cable plane cablestayed bridge with span arrangement (140+140) m and with a structural system of rigid fixity of the pylon, pier and girder. A summarized account of the design and calculation of the superstructure of the bridge is presented herewith. The main girder of the bridge is a composite girder with long cantilevers, the central part of the girder is designed as a two-cell and single-box steel girder and the steel cantilever at each side of the girder is the variable depth I-beam and is provided wiht a trough stringer at the far side, which are all topped with 25 cm thick concrete deck slabs connected with the girder via shearing studs. The part of the main girder close to the pylon is designed as a prestressed concrete box girder to facilitate the fixity of the girder with the pylon. The pylon is the single column pylon, 117 m in height. The stay cables, made up of low relaxation galvanized high strength parallel steel wire strands, are of the harp pattern cable plane arranged in the central alignment of the bridge deck. The finite element software MIDAS Civil 2006 and the SCDS programme are employed to calculate and analyze structure of the bridge. The results of the calculation and analysis indicate that the static, stability and dynamic characteristics of the bridge can meet the requirements in the relevant codes.%乌苏大桥主桥为独塔单索面斜拉桥,跨径布置为(140+140) m,采用塔、墩、梁固结体系,综述该桥上部结构设计与计算.主梁为带大挑臂的钢箱结合梁,中间钢箱梁采用单箱双室截面,两侧钢挑臂为变高度工字形梁,挑臂端部设槽形小纵梁;混凝土桥面板厚25 cm,与钢梁通过剪力钉连接;塔根部主梁采用预应力混凝土箱梁,以方便与桥塔固结;桥塔采用独柱式塔,高117 m;斜拉索为竖琴形中央平行索面布置,采用低松弛镀锌高强度平行钢丝束.采用有限元软件MIDAS Civil

  13. Capacitance bridge detector and signal lock for ion cyclotron resonance spectrometry

    Science.gov (United States)

    Marks, Jeffrey; Drzaic, Paul S.; Foster, Robert F.; Wetzel, Donna M.; Brauman, John I.; Uppal, Jack S.; Staley, Ralph H.

    1987-08-01

    The design and operational characteristics of a capacitance bridge detector and accompanying signal lock system are presented. The signal lock is especially well suited for the measurement of small changes in ion concentration during photochemical experiments, thereby alleviating problems caused by resonant frequency shifts.

  14. Knowledge-Based Systems for the Assessment and Management of Bridge Structures

    DEFF Research Database (Denmark)

    Miyamoto, A.; Thoft-Christensen, Palle; Yan, B.

    2004-01-01

    . The aim of this paper is to summarize the finding of up-to-date research articles concerning the application of knowledge-based systems to assessment and management of structures and to illustrate the potential of such systems in the structural engineering. Two modern bridge management systems (BMS...

  15. Using Mathematics to Bridge the Gap between Biology and Computer Science

    Science.gov (United States)

    Hammerman, Natalie; Tolvo, Anthony; Goldberg, Robert

    2004-01-01

    The rapid rate of expansion of the disciplines of biotechnology, genomics, and bioinformatics emphasizes the increased interdependency between computer science and biology, with mathematics serving as the bridge between these disciplines. This paper demonstrates this inter-relationship within the context of a computational model for a biological…

  16. Intercultural Communication Barriers and Bridges: Talking with High School Teachers about Multi-Culturalism.

    Science.gov (United States)

    Gougeon, Thomas D.; Hutton, Susan I.

    As part of a larger study of school system communication with second language parents in three Alberta (Canada) urban senior high schools, this study focused on analysis of interview data from teachers responding to questions on intercultural communication barriers and bridges with students and immigrant parents. Data were collected through 30…

  17. Authenticity in Learning for the Twenty-First Century: Bridging the Formal and the Informal

    Science.gov (United States)

    Hung, David; Lee, Shu-Shing; Lim, Kenneth Y. T.

    2012-01-01

    The paper attempts to bridge informal and formal learning by leveraging on affordance structures associated with informal environments to help learners develop social, cognitive, and metacognitive dispositions that can be applied to learning in classrooms. Most studies focus on either learning in formal or informal contexts, but this study seeks…

  18. Bridging domains : a comparison between information processing in Archaea and Eukarya

    NARCIS (Netherlands)

    Koning, de B.

    2015-01-01

    Bridging Domains A Comparison between Information Processing in Archaea and Eukarya

    Studying Information Processing Living cells evolved complex systems to handle the flow of information both accurately and efficiently.

  19. Educational Game Design. Bridging the gab between computer based learning and experimental learning environments

    DEFF Research Database (Denmark)

    Andersen, Kristine

    2007-01-01

    Considering the rapidly growing amount of digital educational materials only few of them bridge the gab between experimental learning environments and computer based learning environments (Gardner, 1991). Observations from two cases in primary school and lower secondary school in the subject...

  20. Research and application of non-clay low damage temporary bridging drilling/completion fluids system

    Institute of Scientific and Technical Information of China (English)

    Xiang-zhe Jin; Zai-jun Chen; Bin Yang

    2009-01-01

    Following the basic theory of protecting gas-reservoirs from damage with the temporary bridging technology, inert calcium carbonate (CaCO3) particles, whose diameter is consistent with the size of pores or apertures in the reservoir, were selected as the bridging agent, and modified resolvable starch was selected as filtration loss reducing particles to form the non-clay low damage temporary bridging drilling/completion fluids system (NLTDFS). Under the simulated condition of the well bottom during real drilling, NLTDFS was used to conduct dynamic and static damage experiments of cores for 48 hours, respectively, and then the experimented cores were permeated with pure nitrogen from the undamaged end to the damaged one to measure their recovery of permeability. The results showed that the permeability recovery rate of the core reached 90% or so, and the damaged depth was less than 1 cm, which demonstrates that NL TDFS has higher temporary bridging effectiveness and lower damage to the gas-reservoir than other drilling fluids system. NLTDFS has been used to drill many horizontal wells, and four of them have obtained high yield of natural gas. The yield of natural gas of LPl well reached 85 X 104 m3/day after completion with the rump pipe. The formation of the stable well wall and smooth drilling led to an API loss less than 4 mL and an HTHP loss less than 15 mL.

  1. Impact coefficient and reliability of mid-span continuous beam bridge under action of extra heavy vehicle with low speed

    Institute of Scientific and Technical Information of China (English)

    刘波; 王有志; 胡朋; 袁泉

    2015-01-01

    To analyze the dynamic response and reliability of a continuous beam bridge under the action of an extra heavy vehicle, a vehicle–bridge coupled vibration model was established based on the virtual work principle and vehicle–bridge displacement compatibility equation, which can accurately simulate the dynamic characteristics of the vehicle and bridge. Results show that deck roughness has an important function in the effect of the vehicle on the bridge. When an extra heavy vehicle passes through the continuous beam bridge at a low speed of 5 km/h, the impact coefficient reaches a high value, which should not be disregarded in bridge safety assessments. Considering that no specific law exists between the impact coefficient and vehicle speed, vehicle speed should not be unduly limited and deck roughness repairing should be paid considerable attention. Deck roughness has a significant influence on the reliability index, which decreases as deck roughness increases. For the continuous beam bridge in this work, the reliability index of each control section is greater than the minimum reliability index. No reinforcement measures are required for over-sized transport.

  2. Remote Bridge Deflection Measurement Using an Advanced Video Deflectometer and Actively Illuminated LED Targets.

    Science.gov (United States)

    Tian, Long; Pan, Bing

    2016-01-01

    An advanced video deflectometer using actively illuminated LED targets is proposed for remote, real-time measurement of bridge deflection. The system configuration, fundamental principles, and measuring procedures of the video deflectometer are first described. To address the challenge of remote and accurate deflection measurement of large engineering structures without being affected by ambient light, the novel idea of active imaging, which combines high-brightness monochromatic LED targets with coupled bandpass filter imaging, is introduced. Then, to examine the measurement accuracy of the proposed advanced video deflectometer in outdoor environments, vertical motions of an LED target with precisely-controlled translations were measured and compared with prescribed values. Finally, by tracking six LED targets mounted on the bridge, the developed video deflectometer was applied for field, remote, and multipoint deflection measurement of the Wuhan Yangtze River Bridge, one of the most prestigious and most publicized constructions in China, during its routine safety evaluation tests. Since the proposed video deflectometer using actively illuminated LED targets offers prominent merits of remote, contactless, real-time, and multipoint deflection measurement with strong robustness against ambient light changes, it has great potential in the routine safety evaluation of various bridges and other large-scale engineering structures. PMID:27563901

  3. Remote Bridge Deflection Measurement Using an Advanced Video Deflectometer and Actively Illuminated LED Targets

    Science.gov (United States)

    Tian, Long; Pan, Bing

    2016-01-01

    An advanced video deflectometer using actively illuminated LED targets is proposed for remote, real-time measurement of bridge deflection. The system configuration, fundamental principles, and measuring procedures of the video deflectometer are first described. To address the challenge of remote and accurate deflection measurement of large engineering structures without being affected by ambient light, the novel idea of active imaging, which combines high-brightness monochromatic LED targets with coupled bandpass filter imaging, is introduced. Then, to examine the measurement accuracy of the proposed advanced video deflectometer in outdoor environments, vertical motions of an LED target with precisely-controlled translations were measured and compared with prescribed values. Finally, by tracking six LED targets mounted on the bridge, the developed video deflectometer was applied for field, remote, and multipoint deflection measurement of the Wuhan Yangtze River Bridge, one of the most prestigious and most publicized constructions in China, during its routine safety evaluation tests. Since the proposed video deflectometer using actively illuminated LED targets offers prominent merits of remote, contactless, real-time, and multipoint deflection measurement with strong robustness against ambient light changes, it has great potential in the routine safety evaluation of various bridges and other large-scale engineering structures. PMID:27563901

  4. 淦河桥梁方案设计研究%Design and Research on Bridge Scheme of Gan River

    Institute of Scientific and Technical Information of China (English)

    蔡忠华

    2016-01-01

    Following the principal of applicable,economical,safe and beautiful and taking the bridge crossing Gan River in Jingui west road in Xianning City as the engineering background,four types of bridge design schemes are introduced,namely simple supported girder bridge,continuous girder bridge,through tied-arch bridge,and cable-stayed bridge without backstays.The tied arch bridge is chosen as the recommended proposal by taking bridge design,landscape feature,construction feasibil-ity and economy into comprehensive consideration.%遵循“适用、经济、安全、美观”的桥梁设计基本原则,以咸宁市金桂西路跨淦河大桥为工程背景,提供了4种桥梁设计方案:无背索斜拉桥,预应力混凝土连续梁桥、预应力混凝土简支 T梁桥、下承式系杆拱桥。综合考虑论证桥梁构造设计、景观特色、施工可行性和经济性等因素,选取下承式系杆拱桥作为推荐方案。

  5. A Response to Commentary on Faust, Bridges, and Ahern's (2009) "Methods for the Identification of Sexually Abused Children"

    Science.gov (United States)

    Ahern, David C.; Bridges, Ana J.; Faust, David

    2012-01-01

    Our series of three chapters (Faust, Bridges, & Ahern, 2009a, 2009b; Bridges, Faust, & Ahern, 2009) on the methodology of identifying sexually abused children elicited a number of comments, both supportive and critical. The criticisms appear related to three primary issues or apparent misconceptions of our work, perhaps due in part to incomplete…

  6. Bridging Cultures between Home and School: A Guide for Teachers--With a Special Focus on Immigrant Latino Families.

    Science.gov (United States)

    Trumbull, Elise; Rothstein-Fisch, Carrie; Greenfield, Patricia M.; Quiroz, Blanca

    This book focuses on how to meet the challenges of education in a pluralistic society, presenting the Bridging Cultures framework, which is designed for understanding differences and conflicts that arise in situations where school culture is more individualistic than the home value system. Six sections examine: (1) "The Bridging Cultures…

  7. Evolution and failure of liquid bridges between grains due to evaporation and due to extension

    Science.gov (United States)

    Hueckel, T.; Mielniczuk, B.; Said El Youssoufi, M.

    2012-04-01

    Evolution and rupture of liquid bridges between glass spheres during liquid evaporation and during mechanical extension was examined. The latter type of the tests has been widely studied, while a number of pertinent measurements during transient evaporation have not yet been reported. Also the resultant total capillary forces were measured and geometrical characteristics (curvature radii)were recorded with a photo camera and high-speed camera and subsequently digitalized. The obtained results reveal substantial differences in geometry of liquid bridges during extension and evaporation. On the other hand, evaporation and extension of liquid bridgelead to a similar qualitative response in terms of the pressure within the liquid bridge, starting with a significant suction, which initially somewhat increases during evaporation to reach a maximum, followed by a rapid monotonic decrease until zero, to become a sizable positive pressure prior to rupture. Extension same pattern is followed, except that there is no initial suction increase. Hence, in both cases, rupture consistently occurs at a positive fluid pressure. The pressure evolution is a simple resultant of the evolution of radii of curvature, with the neck radius becoming smaller than meridian radius. In terms of resultant capillary force, as the area of the bridge cross-section decreases with the square of the neck radius, the pressure difference is almost entirely negative, in part also due to surface tension component. Nevertheless, the suction decreases nearly monotonically during both processes. Rupture during evaporation of the bridges occurs most abruptly for larger separations, as early as after 25% volume evaporated. It is seen as a bifurcation of the geometry of equilibrium, as demonstrated on a movie with 27, 000 shots per second. The evolution of a bridge between three spheres exhibits a centrally located thin film instability with a circular hole growing within 1/3000th of a second. All these findings

  8. Bridged graphite oxide materials

    Science.gov (United States)

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

    2010-01-01

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

  9. Update of Columbia River flow and temperature data measured at Priest Rapids Dam and Vernita Bridge

    Energy Technology Data Exchange (ETDEWEB)

    Whelan, G.; Newbill, C.A.

    1983-09-01

    Columbia River temperatures and flow rates are collected daily at Priest Rapids Dam and Vernita Bridge. These data are necessary for assessing trends or changes in river conditions downstream of Priest Rapids Dam. In order to analyze this data, Pacific Northwest Laboratory developed a computerized data base using existing US Geological Survey flow and temperature records at Priest Rapids Dam and Vernita Bridge. Daily-averaged temperature and daily flow information on the Columbia River just downstream of Priest Rapids Dam and upstream of river mile 380 were collected and stored in a data base. A newly developed computer model, COLSTAT (Columbia River Statistical Update), used the data base to statistically analyze temperature and flow conditions by computing the frequency of occurrence and duration of selected temperatures and flow rates for the Columbia River. Information regarding the data base is presented, as well as, a description of the COLSTAT model.

  10. High Frequency AC Inductor Analysis and Design for Dual Active Bridge (DAB) Converters

    DEFF Research Database (Denmark)

    Zhang, Zhe; Andersen, Michael A. E.

    2016-01-01

    The dual active bridge (DAB) converter is an isolated bidirectional dc-dc topology which is the most critical part for the power conversion systems such as solid-state transformers (SST). This paper focuses on analysis and design of high frequency ac inductors which are the power interfacing...

  11. Bioinformatics and Systems Biology: bridging the gap between heterogeneous student backgrounds.

    NARCIS (Netherlands)

    S. Abeln; D. Molenaar; K.A. Feenstra; H.C.J. Hoefsloot; B. Teusink; J. Heringa

    2013-01-01

    Teaching students with very diverse backgrounds can be extremely challenging. This article uses the Bioinformatics and Systems Biology MSc in Amsterdam as a case study to describe how the knowledge gap for students with heterogeneous backgrounds can be bridged. We show that a mix in backgrounds can

  12. Research and Teaching: Association of Summer Bridge Program Outcomes with STEM Retention of Targeted Demographic Groups

    Science.gov (United States)

    Tomasko, David L.; Ridgway, Judith S.; Waller, Rocquel J.; Olesik, Susan V.

    2016-01-01

    Retention of students to science, technology, engineering, and mathematics (STEM) major has been studied for four cohorts participating in a summer bridge program supported by the National Science Foundation. Students participated in a 6-week program prior to their first term of enrollment at a research-intensive land grant university. Comparisons…

  13. Bridging the Gap between Practitioners and E-learning Standards: A Domain-specific Modeling Approach

    NARCIS (Netherlands)

    Miao, Yongwu; Sodhi, Tim; Brouns, Francis; Sloep, Peter; Koper, Rob

    2008-01-01

    Miao, Y., Sodhi, T., Brouns, F., Sloep, P. B., & Koper, R. (2008). Bridging the Gap between Practitioners and E-learning Standards: A Domain-Specific Modeling Approach. In P. Dillenbourg & M. Specht (Eds.), Times of Convergence. Technologies Across Learning Contexts - Proceedings of the Third Europe

  14. Comparison of the aerodynamics of bridge cables with helical fillets and a pattern-indented surface

    DEFF Research Database (Denmark)

    Kleissl, K.; Georgakis, C.T.

    2012-01-01

    In this paper, the aerodynamics of bridge cables with helical fillets and a pattern-indented surface are examined. To this end, an extensive wind-tunnel test campaign was undertaken to measure the static force coefficients about the critical Reynolds number region, with varying relative cable...

  15. Carbon fiber-reinforced polymer strengthening and monitoring of the grondals bridge in Sweden

    DEFF Research Database (Denmark)

    Täljsten, Björn; Hejll, Arvid; James, Gerard

    2007-01-01

    strengthened. The strengthening methods used were CFRP plates at the serviceability limit state and prestressed dywidag stays at the ultimate limit state. The strengthening was carried out during 2002. At the same time monitoring of the bridge commenced, using LVDT crack gauges as well as optical fiber sensors....

  16. Bridging the Gap between Practitioners and E-learning Standards: A Domain-specific Modeling Approach

    NARCIS (Netherlands)

    Miao, Yongwu; Sodhi, Tim; Brouns, Francis; Sloep, Peter; Koper, Rob

    2009-01-01

    Miao, Y., Sodhi, T., Brouns, F., Sloep, P. B., & Koper, R. (2008). Bridging the Gap between Practitioners and E-learning Standards: A Domain-Specific Modeling Approach. Presentation at the ECTEL 2008 conference. September, 16-19, 2008, Maastricht, The Netherlands.

  17. Effects of polar cortical cytoskeleton and unbalanced cortical surface tension on intercellular bridge thinning during cytokinesis

    Institute of Scientific and Technical Information of China (English)

    Li Wang; Mei-Wen An; Xiao-Na Li; Fang Yang; Yang Liu

    2011-01-01

    To probe the contributions of polar cortical cytoskeleton and the surface tension of daughter cells to intercellular bridgethinning dynamics during cytokinesis,we applied cytochalasin D (CD) or colchicine (COLC) in a highly localized manner to polar regions of dividing normal rat kidney (NRK) cells.We observed cellular morphological changes and analyzed the intercellular bridge thinning trajectories of dividing cells with different polar cortical characteristics.Global blebbistatin (BS) application was used to obtain cells losing active contractile force groups.Our results show that locally released CD or colchicine at the polar region caused inhibition of cytokinesis before ingression.Similar treatment at phases after ingression allowed completion of cytokinesis but dramatically influenced the trajectories of intercellular bridge thinning.Disturbing single polar cortical actin induced transformation of the intercellular bridge thinning process,and polar cortical tension controlled deformation time of intercellular bridges.Our study provides a feasible framework to induce and analyze the effects of local changes in mechanical properties of cellular components on single cellular cytokinesis.

  18. Repair and strengthening of R/C bridges degraded by environmental actions and pollution

    OpenAIRE

    Benedetti, Andrea; Donchev, Ted; Pelà, Luca

    2012-01-01

    Many bridges all around the world experience very hard environmental conditions, and due to the irregular maintenance effort, show different problems of cracking, concrete cover detachment and steel reinforcement wear and corrosion. In general, as a consequence of the polluted rain wetting, the problem is more evident in vertical structures than in the horizontal ones, and serious problems can arise when the piers and columns are very tall. In recent times, the solutions offered by composite ...

  19. Polarizers, optical bridges and Sagnac interferometers for nanoradian polarization rotation measurements

    CERN Document Server

    Rowe, Alistair; Dilasser, Guillaume; Lassailly, Yves; Peretti, Jacques

    2016-01-01

    The ability to measure nanoradian polarization rotations, $\\theta_F$, in the photon shot noise limit is investigated for partially crossed polarizers (PCP), a static Sagnac interferometer and an optical bridge, each of which can in principal be used in this limit with equivalent figures-of-merit (FOM). In practice a common mode source noise rejection ratio of $1/2\\theta_F$ obtained with the bridge enables this configuration to operate in the photon shot noise limit even at high light intensities. This is demonstrated for a rotation angle of 38 $\\mu$rad, obtained via the Faraday effect in a terbium gallium garnet (TGG), where the experimentally measured FOM in units of $10^{-11}$/photon are 2 (PCP), 1 (Sagnac), and 3.5 (bridge). The superior performance of the bridge is illustrated via the measurement of a 3 nrad rotation occuring when the TGG is placed in an axial magnetic field of 0.9 nT. While the Sagnac is shown to be functionally equivalent to the PCP in terms of the FOM, unlike the PCP it is able to disc...

  20. Dynamic approach to space and habitat use based on biased random bridges.

    Directory of Open Access Journals (Sweden)

    Simon Benhamou

    Full Text Available BACKGROUND: Although habitat use reflects a dynamic process, most studies assess habitat use statically as if an animal's successively recorded locations reflected a point rather than a movement process. By relying on the activity time between successive locations instead of the local density of individual locations, movement-based methods can substantially improve the biological relevance of utilization distribution (UD estimates (i.e. the relative frequencies with which an animal uses the various areas of its home range, HR. One such method rests on Brownian bridges (BBs. Its theoretical foundation (purely and constantly diffusive movements is paradoxically inconsistent with both HR settlement and habitat selection. An alternative involves movement-based kernel density estimation (MKDE through location interpolation, which may be applied to various movement behaviours but lacks a sound theoretical basis. METHODOLOGY/PRINCIPAL FINDINGS: I introduce the concept of a biased random (advective-diffusive bridge (BRB and show that the MKDE method is a practical means to estimate UDs based on simplified (isotropically diffusive BRBs. The equation governing BRBs is constrained by the maximum delay between successive relocations warranting constant within-bridge advection (allowed to vary between bridges but remains otherwise similar to the BB equation. Despite its theoretical inconsistencies, the BB method can therefore be applied to animals that regularly reorientate within their HRs and adapt their movements to the habitats crossed, provided that they were relocated with a high enough frequency. CONCLUSIONS/SIGNIFICANCE: Biased random walks can approximate various movement types at short times from a given relocation. Their simplified form constitutes an effective trade-off between too simple, unrealistic movement models, such as Brownian motion, and more sophisticated and realistic ones, such as biased correlated random walks (BCRWs, which are too