Teknologvurdering, Broer og Brugere (Technology Assessment: Bridges and Users)

DEFF Research Database (Denmark)

Munch, Birgitte

A critique of the scientific approaches grounding Danish technology assessments for beingnon-reflexive upon the consequences of its biased treatment of who and how some countsas ‘users'. Implications and new approaches are outlined in a story of engineering designers conceptualization of ships pa...... passing the Great Belt - the ‘sailing users' - during the constructionof the suspension bridge across the east channel. A story about 'How the Great BeltEast bridge main span got the length of 1624m....

Field dynamic testing on a Cyprus concrete highway bridge using Wireless Sensor Network (WSN)

Science.gov (United States)

Votsis, Renos A.; Kyriakides, Nicholas; Tantele, Elia A.; Chrysostomou, Christis Z.; Onoufriou, Toula

2014-08-01

The aims of the bridge management authorities are to ensure that bridges fulfil their purpose and functionality during their design life. So, it is important to identify and quantify the deterioration of the structural condition early so that a timely application of an intervention will avoid more serious problems and increased costs at a later stage. A measure to enhance the effectiveness of the existing structural evaluation by visual inspection is instrumental monitoring using sensors. The activities performed in this process belong to the field of Structural Health Monitoring (SHM). The SHM offers opportunities for continuous or periodic monitoring on bridges and technological advances allow nowadays the employment of wireless sensors networks (WSN) for this task. A SHM application using WSN was implemented on a multi-span reinforced concrete (RC) highway bridge in Limassol with the objective to study its dynamic characteristics and performance. Part of the specific bridge will be replaced and this offered a unique opportunity for measurements before and after construction so that apparent changes in the dynamic characteristics of the bridge will be identified after the repairing work. The measurements provided indications on the frequencies and mode shapes of the bridge and the response amplitude during the passing of traffic. The latter enabled the investigation of the dependency of the bridge's structural damping to the amplitude of vibration induced by the passing of traffic. The results showed that as the excitation increases the magnitude of modal damping increases as well.

Bridge Diagnosis by Using Nonlinear Independent Component Analysis and Displacement Analysis

Science.gov (United States)

Zheng, Juanqing; Yeh, Yichun; Ogai, Harutoshi

A daily diagnosis system for bridge monitoring and maintenance is developed based on wireless sensors, signal processing, structure analysis, and displacement analysis. The vibration acceleration data of a bridge are firstly collected through the wireless sensor network by exerting. Nonlinear independent component analysis (ICA) and spectral analysis are used to extract the vibration frequencies of the bridge. After that, through a band pass filter and Simpson's rule the vibration displacement is calculated and the vibration model is obtained to diagnose the bridge. Since linear ICA algorithms work efficiently only in linear mixing environments, a nonlinear ICA model, which is more complicated, is more practical for bridge diagnosis systems. In this paper, we firstly use the post nonlinear method to change the signal data, after that perform linear separation by FastICA, and calculate the vibration displacement of the bridge. The processed data can be used to understand phenomena like corrosion and crack, and evaluate the health condition of the bridge. We apply this system to Nakajima Bridge in Yahata, Kitakyushu, Japan.

Yonjung High-Speed Railway Bridge Assessment Using Output-Only Structural Health Monitoring Measurements under Train Speed Changing

Directory of Open Access Journals (Sweden)

Mosbeh R. Kaloop

2016-01-01

Full Text Available Yonjung Bridge is a hybrid multispan bridge that is designed to transport high-speed trains (HEMU-430X with maximum operating speed of 430 km/h. The bridge consists of simply supported prestressed concrete (PSC and composite steel girders to carry double railway tracks. The structural health monitoring system (SHM is designed and installed to investigate and assess the performance of the bridge in terms of acceleration and deformation measurements under different speeds of the passing train. The SHM measurements are investigated in both time and frequency domains; in addition, several identification models are examined to assess the performance of the bridge. The drawn conclusions show that the maximum deflection and acceleration of the bridge are within the design limits that are specified by the Korean and European codes. The parameters evaluation of the model identification depicts the quasistatic and dynamic deformations of PSC and steel girders to be different and less correlated when higher speeds of the passing trains are considered. Finally, the variation of the frequency content of the dynamic deformations of the girders is negligible when high speeds are considered.

High-speed railway bridge dynamic measurement based on GB-InSAR technology

Science.gov (United States)

Liu, Miao; Ding, Ke-liang; Liu, Xianglei; Song, Zichao

2015-12-01

It is an important task to evaluate the safety during the life of bridges using the corresponding vibration parameters. With the advantages of non-contact and high accuracy, the new remote measurement technology of GB-InSAR is suitable to make dynamic measurement for bridges to acquire the vibration parameters. Three key technologies, including stepped frequency-continuous wave technique, synthetic aperture radar and interferometric measurement technique, are introduced in this paper. The GB-InSAR is applied for a high-speed railway bridge to measure of dynamic characteristics with the train passing which can be used to analyze the safety of the monitored bridge. The test results shown that it is an reliable non-contact technique for GB-InSAR to acquire the dynamic vibration parameter for the high-speed railway bridges.

Tresfjord Bridge - a human friendly and traffic efficient structure

Science.gov (United States)

Dahl, Kristian B.; Anta Magerøy Tønnessen, Aja; Toverud, Lars I.

2017-09-01

The E136 Tresfjord Bridge opened in October 2015, and crosses the Tresfjorden on the west coast of Norway. It is a concrete bridge with a total length of 1290 m, consisting of 19 viaduct spans, 60 m each, and a FCM (free cantilever method) main span of 160 m. The E136 is one of the most important transportation routes in the county of Møre and Romsdal and starts in Ålesund, and passes along Tresfjorden to Åndalsnes. The existing road is very narrow with speed limit of 60 km/h and characterizes by many accidents involving cars and people. The traffic flow is approximately ca 2500 vehicles a day, of this is 25% heavy vehicles. Those transport fresh salmon from the breeders in the fjords along the coast. To try to decrease the transportation time is very important for the fresh salmon. The bridge reduces the distance between Ålesund and Åndalsnes by 13 km. The speed limit is now 80 km/h, and with much less risk for accidents since there are separate lanes for cars and pedestrians over the whole bridge. This means that the bridge represents a human friendly and traffic efficient structure to the benefit for the people and the region.

Cable-stayed PC bridge with inclined main tower. Hachinohe port island bridge; Keisha shuto to yusuru 2 keikan renzoku PC shachokyo. Hachinoheko port island renrakykyo (kasho)

Energy Technology Data Exchange (ETDEWEB)

Hasegawa, A. [Hachinohe Institute of Technology, Aomori (Japan)

1994-09-15

The design and construction of the inclined main bridge, which is being constructed at the mouth of the Hachinohe Harbor (in Japan), are outlined in this paper. This connecting bridge has an overall length of 265.56 m, and consists of the main bridge member of asymmetric 2 cable-stayed PC bridge and the 3 cable-stayed PC box member bridge. An asymmetric design was employed for the main bridge frame to ensure the access space for small ships passing between bridge girders, easy maintenance and service, improved economy, and excellent view. The main tower is a single-pillar reinforced concrete structure with an inclination of 15{degree} and 47 m in height. Forty-eight diagonal cables are arranged so that 12 cable trains are connected to the main tower on the right and left sides respectively, and the back-stay cable structure is used for each upper 3 cable trains to improve safety against the earthquake. The main beam is made by a prestressed concrete structure with inverse trapezoidal 3-chamber frame section. This structure is superior in increasing the safety against wind. Steel tube sheet-pile well is selected for the bridge pier base, and debris layer is selected as a support layer for the base. For the construction of the lower bridge section, sand conversion through predrilling of rubble-mound and debris layer was executed. The underwater non-separative concrete and embedded type frame are used around the bridge piers and its surrounding. For the construction of the upper bridge section, steel frames are used inside the main tower to ensure the construction precision. 7 figs.

Sex Difference in Bottlenose Dolphin Sightings during a Long-term Bridge Construction Project

Directory of Open Access Journals (Sweden)

Ann Weaver

2015-02-01

Full Text Available Almost nothing is known about the effect of long-term bridge construction on free-ranging bottlenose dolphins (Tursiops truncatus. The species’ natural history predicts that there should be sex differences in reaction to construction because bottlenose dolphins show sex differences in most of their behaviors. A 5-year bridge construction project over a narrow but important dolphin corridor at John’s Pass tidal inlet, St. Petersburg FL, brought chronic environmental changes. The purpose of this 8-year study was to determine if bridge construction was associated with changes in dolphin sightings. The sex difference hypothesis was tested with a comparison of sighting probabilities before, during and after bridge construction. Sighting probabilities were generated for 68 adults seen n = 6504 times during N = 951 small-boat surveys of the 6.5-mile estuarine study area, documented with photo identification June 2005-December 2012. The sex difference hypothesis was supported with a significant interaction between construction and gender. Female sightings showed a significant linear decline across construction. Male sightings did not change across construction. The main conclusion is that adult males and females may react differently to habitat changes associated with anthropogenic activities. Sex differences in environmental monitoring and vigilance associated with maternal behavior may have played a role. This is the first report on John’s Pass dolphins that evaluates changes in their behavior during a major construction project across a narrow but important dolphin corridor.

Copper ion fluxes through the floating water bridge under strong electric potential.

Science.gov (United States)

Giuliani, Livio; D'Emilia, Enrico; Lisi, Antonella; Grimaldi, Settimio; Brizhik, Larissa; Del Giudice, Emilio

2015-01-01

We have performed a series of experiments applying high voltage between two electrodes, immersed in two beakers containing bidistilled water in a way similar to experiments conducted by Fuchs and collaborators, which showed that a water bridge can be formed between the two containers. We also observed the formation of water bridge. Moreover, choosing different pairs of electrodes depending on the material they are made up of, we observed that copper ions flow can pass along the bridge if the negative electrode is made up of copper. We show that the direction of the flux not only depends on the applied electrostatic field but on the relative electronegativity of the electrodes too. These results open new perspectives in understanding the properties of water. We suggest a possible explanation of the obtained results.

Note: A non-invasive electronic measurement technique to measure the embedded four resistive elements in a Wheatstone bridge sensor

International Nuclear Information System (INIS)

Ravelo Arias, S. I.; Ramírez Muñoz, D.; Cardoso, S.; Ferreira, R.; Freitas, P.

2015-01-01

The work shows a measurement technique to obtain the correct value of the four elements in a resistive Wheatstone bridge without the need to separate the physical connections existing between them. Two electronic solutions are presented, based on a source-and-measure unit and using discrete electronic components. The proposed technique brings the possibility to know the mismatching or the tolerance between the bridge resistive elements and then to pass or reject it in terms of its related common-mode rejection. Experimental results were taken in various Wheatstone resistive bridges (discrete and magnetoresistive integrated bridges) validating the proposed measurement technique specially when the bridge is micro-fabricated and there is no physical way to separate one resistive element from the others

Note: A non-invasive electronic measurement technique to measure the embedded four resistive elements in a Wheatstone bridge sensor

Energy Technology Data Exchange (ETDEWEB)

Ravelo Arias, S. I.; Ramírez Muñoz, D. [Department of Electronic Engineering, University of Valencia, Avda. de la Universitat, s/n, 46100-Burjassot (Spain); Cardoso, S. [INESC Microsystems and Nanotechnologies (INESC-MN) and Institute for Nanosciences and Nanotechnologies, R. Alves Redol 9, Lisbon 1000-029 (Portugal); Ferreira, R. [INL-International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga, Braga 4715-31 (Portugal); Freitas, P. [INESC Microsystems and Nanotechnologies (INESC-MN) and Institute for Nanosciences and Nanotechnologies, R. Alves Redol 9, Lisbon 1000-029 (Portugal); INL-International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga, Braga 4715-31 (Portugal)

2015-06-15

The work shows a measurement technique to obtain the correct value of the four elements in a resistive Wheatstone bridge without the need to separate the physical connections existing between them. Two electronic solutions are presented, based on a source-and-measure unit and using discrete electronic components. The proposed technique brings the possibility to know the mismatching or the tolerance between the bridge resistive elements and then to pass or reject it in terms of its related common-mode rejection. Experimental results were taken in various Wheatstone resistive bridges (discrete and magnetoresistive integrated bridges) validating the proposed measurement technique specially when the bridge is micro-fabricated and there is no physical way to separate one resistive element from the others.

77 FR 1407 - Regulated Navigation Area; Memorial Bridge Construction, Piscataqua River, Portsmouth, NH

Science.gov (United States)

2012-01-10

... like to know that they reached the Facility, please enclose a stamped, self-addressed postcard or..., and wake from passing vessels could pose significant risk of injury or death to construction workers... speed and wake of all vessels operating in the vicinity of the bridge construction zone. This will be...

Using weigh-in-motion data to determine bridge dynamic amplification factor

Directory of Open Access Journals (Sweden)

Kalin Jan

2015-01-01

Full Text Available The dynamic component of bridge traffic loading is commonly taken into account with a Dynamic Amplification Factor (DAF – the ratio between the maximum dynamic and static load effects on a bridge. In the design codes, this factor is generally higher than in reality. While this is fine for new bridges that must account for various risks during their life-time, it imposes unnecessary conservativism into assessment of the existing well defined bridges. Therefore, analysis of existing bridges should apply more realistic DAF values. One way of obtaining them experimentally is by bridge weigh-in-motion (B-WIM measurements, which use an existing instrumented bridge or culvert to weigh all crossing vehicles at highway speeds. The B-WIM system had been equipped with two methods of obtaining an approximation to the static response of the. The first method uses the sum of influence lines. This method relies on accurate axle identification, the failure of which can have a large influence on the DAF value. The other method uses a pre-determined low-pass filter to remove the dynamic component of the measured signal; however an expert is needed to set the filter parameters. A new approach that tries to eliminate these two drawbacks has been developed. In this approach the parameters for the filter are determined automatically by fitting the filtered response to the sum of the influence lines. The measurement of DAF on a typical bridge site agrees with experiments performed in the ARCHES [1] project: dynamic amplification decreases as static loading increases.

Dynamic response of the train-track-bridge system subjected to derailment impacts

Science.gov (United States)

Ling, Liang; Dhanasekar, Manicka; Thambiratnam, David P.

2018-04-01

Derailments on bridges, although not frequent, when occurs due to a complex dynamic interaction of the train-track-bridge structural system, are very severe. Furthermore, the forced vibration induced by the post-derailment impacts can toss out the derailed wagons from the bridge deck with severe consequences to the traffic underneath and the safety of the occupants of the wagons. This paper presents a study of the train-track-bridge interaction during a heavy freight train crossing a concrete box girder bridge from a normal operation to a derailed state. A numerical model that considers the bridge vibration, train-track interaction and the train post-derailment behaviour is formulated based on a coupled finite-element - multi-body dynamics (FE-MBD) theory. The model is applied to predict the post-derailment behaviour of a freight train composed of one locomotive and several wagons, as well as the dynamic response of a straight single-span simply supported bridge containing ballast track subjected to derailment impacts. For this purpose, a typical derailment scenario of a heavy freight train passing over a severe track geometry defect is introduced. The dynamic derailment behaviour of the heavy freight train and the dynamic responses of the rail bridge are illustrated through numerical examples. The results exhibit the potential for tossing out of the derailed trains from the unstable increase in the yaw angle signature and a lower rate of increase of the bridge deck bending moment compared to the increase in the static axle load of the derailed wheelset.

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

Science.gov (United States)

2010-10-01

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

GPS for structural health monitoring : A case study on the Basarab overpass cable-stayed bridge

NARCIS (Netherlands)

Lepadatu, L.; Tiberius, C.C.J.M.

2014-01-01

The Basarab cable-stayed bridge is a newly built structure in Bucharest, Romania, which was inaugurated in June 2011. Before the oficial opening, in order to assure its qualification for trafic, it had to pass several loading tests with convoys of trucks and trams. For this, besides a priori

Monitoring the Como Railway Bridge based on dynamic FBG sensor system

Science.gov (United States)

Zhang, Jianzhong; Sun, Weimin; Peng, G. D.; Yuan, Libo

2007-07-01

A FBG-based dynamic strain sensor system, whose responding frequency and resolution can be high as 16Hz and ~1μɛ respectively, is described and the system is applied to monitor the dynamic strain of Como Railway Bridge in Australia. The results of one-month long measurement show that the system can figure out all dynamic strain caused by passed trains and also prove the stability of the sensor system.

Construction of the Usui bridge. Chodai PC shachokyo no kensetsu (Joshin'etsu jidoshado Usuikyo)

Energy Technology Data Exchange (ETDEWEB)

Otani, S.; Ogata, T. (Japan Highway Public Corp., Tokyo (Japan))

1993-10-01

The Usui Bridge is a long bridge located at the Usui mountain pass on the Joshinetsu Expressway, completed in March 1993. This paper reports from its planning to the design, construction work, and construction management. The bridge is a first two-span continuous prestressed concrete cable-stayed bridge (with a length of 222 m) with one central cable plane ever constructed as a highway bridge in Japan. Its bridge construction features are represented by the main girder consisted of three-chamber type box girder, and the main tower of reversed Y-letter concrete structure. For the fan-shaped stay cable (9-step double cable), a large capacity cable of non-grouting type fabricated at a factory (with a tensile strength of 1500 tf class) was used to simplify the installation work at the site. The one-plane structure utilizing the center belt as a stay cable fixing portion was adopted because of its economic performance superior to a two-plane structure, easiness in consolidating construction works, and assurance of more open space for car traffic. After the completion, the bridge construction has been awarded with the Tanaka Prize of Japan Society of Civil Engineers and the PC Technology Association prize. 26 figs., 4 tabs.

INVESTIGATION OF SINGLE-PASS/DOUBLE-PASS TECHNIQUES ON FRICTION STIR WELDING OF ALUMINIUM

Directory of Open Access Journals (Sweden)

N.A.A. Sathari

2014-12-01

Full Text Available The aim of this research is to study the effects of single-pass/ double-pass techniques on friction stir welding of aluminium. Two pieces of AA1100 with a thickness of 6.0 mm were friction stir welded using a CNC milling machine at rotational speeds of 1400 rpm, 1600 rpm and 1800 rpm respectively for single-pass and double-pass. Microstructure observations of the welded area were studied using an optical microscope. The specimens were tested by using a tensile test and Vickers hardness test to evaluate their mechanical properties. The results indicated that, at low rotational speed, defects such as ‘surface lack of fill’ and tunnels in the welded area contributed to a decrease in mechanical properties. Welded specimens using double-pass techniques show increasing values of tensile strength and hardness. From this investigation it is found that the best parameters of FSW welded aluminium AA1100 plate were those using double-pass techniques that produce mechanically sound joints with a hardness of 56.38 HV and 108 MPa strength at 1800 rpm compared to the single-pass technique. Friction stir welding, single-pass/ double-pass techniques, AA1100, microstructure, mechanical properties.

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

Science.gov (United States)

2010-10-01

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

Passing and Catching in Rugby.

Science.gov (United States)

Namudu, Mike M.

This booklet contains the fundamentals for rugby at the primary school level. It deals primarily with passing and catching the ball. It contains instructions on (1) holding the ball for passing, (2) passing the ball to the left--standing, (3) passing the ball to the left--running, (4) making a switch pass, (5) the scrum half's normal pass, (6) the…

Passing Decisions in Football: Introducing an Empirical Approach to Estimating the Effects of Perceptual Information and Associative Knowledge.

Science.gov (United States)

Steiner, Silvan

2018-01-01

The importance of various information sources in decision-making in interactive team sports is debated. While some highlight the role of the perceptual information provided by the current game context, others point to the role of knowledge-based information that athletes have regarding their team environment. Recently, an integrative perspective considering the simultaneous involvement of both of these information sources in decision-making in interactive team sports has been presented. In a theoretical example concerning passing decisions, the simultaneous involvement of perceptual and knowledge-based information has been illustrated. However, no precast method of determining the contribution of these two information sources empirically has been provided. The aim of this article is to bridge this gap and present a statistical approach to estimating the effects of perceptual information and associative knowledge on passing decisions. To this end, a sample dataset of scenario-based passing decisions is analyzed. This article shows how the effects of perceivable team positionings and athletes' knowledge about their fellow team members on passing decisions can be estimated. Ways of transfering this approach to real-world situations and implications for future research using more representative designs are presented.

Passing Decisions in Football: Introducing an Empirical Approach to Estimating the Effects of Perceptual Information and Associative Knowledge

Directory of Open Access Journals (Sweden)

Silvan Steiner

2018-03-01

Full Text Available The importance of various information sources in decision-making in interactive team sports is debated. While some highlight the role of the perceptual information provided by the current game context, others point to the role of knowledge-based information that athletes have regarding their team environment. Recently, an integrative perspective considering the simultaneous involvement of both of these information sources in decision-making in interactive team sports has been presented. In a theoretical example concerning passing decisions, the simultaneous involvement of perceptual and knowledge-based information has been illustrated. However, no precast method of determining the contribution of these two information sources empirically has been provided. The aim of this article is to bridge this gap and present a statistical approach to estimating the effects of perceptual information and associative knowledge on passing decisions. To this end, a sample dataset of scenario-based passing decisions is analyzed. This article shows how the effects of perceivable team positionings and athletes' knowledge about their fellow team members on passing decisions can be estimated. Ways of transfering this approach to real-world situations and implications for future research using more representative designs are presented.

Myocardial Bridge

Science.gov (United States)

... Center > Myocardial Bridge Menu Topics Topics FAQs Myocardial Bridge En español Your heart is made of muscle, ... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart ...

A Study on Assessment Method of Traffic Load Effect of Bridge in Service

Science.gov (United States)

Ling, Pan; Dajian, Han

2010-05-01

Because of overloading usually occur in highway in China today, it is found that the traffic load and the load effects given by Specification for Inspection and Evaluation of Load-bearing Capacity of Highway Bridge[1] cannot be adequately estimated. Especially, the extreme values in a service period can not be predicted. In this paper, a model is first developed for a better estimation of the actual traffic flow, as well as the service load effect level of a bridge. Based on a five-day collection data of the vehicle samples passing through the exit of Guangyuan to Shahe of the North-Ring Highway in Guangzhou, The Qiaole Bridge of the highway is taken as an example to illustrate the assessment model. Then, a threshold model is applied to estimate the tail distribution of the maximum load effect of a fleet. And threshold point process is used to infer the maximum value distribution for prediction of the load effect level of the bridge in a future time period. Finally, a 0.95 quantile is obtained to compare with the result given by specification[1]. The results show that the assessment method proposed in this paper is valid and feasible.

Multi-pass spectroscopic ellipsometry

International Nuclear Information System (INIS)

Stehle, Jean-Louis; Samartzis, Peter C.; Stamataki, Katerina; Piel, Jean-Philippe; Katsoprinakis, George E.; Papadakis, Vassilis; Schimowski, Xavier; Rakitzis, T. Peter; Loppinet, Benoit

2014-01-01

Spectroscopic ellipsometry is an established technique, particularly useful for thickness measurements of thin films. It measures polarization rotation after a single reflection of a beam of light on the measured substrate at a given incidence angle. In this paper, we report the development of multi-pass spectroscopic ellipsometry where the light beam reflects multiple times on the sample. We have investigated both theoretically and experimentally the effect of sample reflectivity, number of reflections (passes), angles of incidence and detector dynamic range on ellipsometric observables tanΨ and cosΔ. The multiple pass approach provides increased sensitivity to small changes in Ψ and Δ, opening the way for single measurement determination of optical thickness T, refractive index n and absorption coefficient k of thin films, a significant improvement over the existing techniques. Based on our results, we discuss the strengths, the weaknesses and possible applications of this technique. - Highlights: • We present multi-pass spectroscopic ellipsometry (MPSE), a multi-pass approach to ellipsometry. • Different detectors, samples, angles of incidence and number of passes were tested. • N passes improve polarization ratio sensitivity to the power of N. • N reflections improve phase shift sensitivity by a factor of N. • MPSE can significantly improve thickness measurements in thin films

Split-cross-bridge resistor for testing for proper fabrication of integrated circuits

Science.gov (United States)

Buehler, M. G. (Inventor)

1985-01-01

An electrical testing structure and method is described whereby a test structure is fabricated on a large scale integrated circuit wafer along with the circuit components and has a van der Pauw cross resistor in conjunction with a bridge resistor and a split bridge resistor, the latter having two channels each a line width wide, corresponding to the line width of the wafer circuit components, and with the two channels separated by a space equal to the line spacing of the wafer circuit components. The testing structure has associated voltage and current contact pads arranged in a two by four array for conveniently passing currents through the test structure and measuring voltages at appropriate points to calculate the sheet resistance, line width, line spacing, and line pitch of the circuit components on the wafer electrically.

The Akashi Kaikyo Bridge and the Storebælt Bridge

DEFF Research Database (Denmark)

Gimsing, Niels Jørgen

1999-01-01

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

Monitoring the dynamic behaviors of the Bosporus Bridge by GPS during Eurasia Marathon

Directory of Open Access Journals (Sweden)

H. Erdoğan

2007-08-01

Full Text Available Engineering structures, like bridges, dams and towers are designed by considering temperature changes, earthquakes, wind, traffic and pedestrian loads. However, generally, it can not be estimated that these structures may be affected by special, complex and different loads. So it could not be known whether these loads are dangerous for the structure and what the response of the structures would be to these loads. Such a situation occurred on the Bosporus Bridge, which is one of the suspension bridges connecting the Asia and Europe continents, during the Eurasia Marathon on 2 October 2005, in which 75 000 pedestrians participated. Responses of the bridge to loads such as rhythmic running, pedestrian walking, vehicle passing during the marathon were observed by a real-time kinematic (RTK Global Positioning System (GPS, with a 2.2-centimeter vertical accuracy. Observed responses were discussed in both time domain and frequency domain by using a time series analysis. High (0.1–1 Hz and low frequencies (0.00036–0.01172 Hz of observed bridge responses under 12 different loads which occur in different quantities, different types and different time intervals were calculated in the frequency domain. It was seen that the calculated high frequencies are similar, except for the frequencies of rhythmic running, which causes a continuously increasing vibration. Any negative response was not determined, because this rhythmic effect continued only for a short time. Also when the traffic load was effective, explicit changes in the bridge movements were determined. Finally, it was seen that bridge frequencies which were calculated from the observations and the finite element model were harmonious. But the 9th natural frequency value of the bridge under all loads, except rhythmic running could not be determined with observations.

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....

Ultrastructural evaluation of multiple pass low energy versus single pass high energy radio-frequency treatment.

Science.gov (United States)

Kist, David; Burns, A Jay; Sanner, Roth; Counters, Jeff; Zelickson, Brian

2006-02-01

The radio-frequency (RF) device is a system capable of volumetric heating of the mid to deep dermis and selective heating of the fibrous septa strands and fascia layer. Clinically, these effects promote dermal collagen production, and tightening of these deep subcutaneous structures. A new technique of using multiple low energy passes has been described which results in lower patient discomfort and fewer side effects. This technique has also been anecdotally described as giving more reproducible and reliable clinical results of tissue tightening and contouring. This study will compare ultrastructural changes in collagen between a single pass high energy versus up to five passes of a multiple pass lower energy treatment. Three subjects were consented and treated in the preauricular region with the RF device using single or multiple passes (three or five) in the same 1.5 cm(2) treatment area with a slight delay between passes to allow tissue cooling. Biopsies from each treatment region and a control biopsy were taken immediately, 24 hours or 6 months post treatment for electron microscopic examination of the 0-1 mm and 1-2 mm levels. Sections of tissue 1 mm x 1 mm x 80 nm were examined with an RCA EMU-4 Transmission Electron Microscope. Twenty sections from 6 blocks from each 1 mm depth were examined by 2 blinded observers. The morphology and degree of collagen change in relation to area examined was compared to the control tissue, and estimated using a quantitative scale. Ultrastructural examination of tissue showed that an increased amount of collagen fibril changes with increasing passes at energies of 97 J (three passes) and 122 J (five passes), respectively. The changes seen after five multiple passes were similar to those detected after much more painful single pass high-energy treatments. This ultrastructural study shows changes in collagen fibril morphology with an increased effect demonstrated at greater depths of the skin with multiple low-fluence passes

TPG bus passes

CERN Multimedia

Staff Association

2013-01-01

The CERN Staff Association will stop selling TPG bus passes. All active and retired members of the CERN personnel will be able to purchase Unireso bus passes from the CERN Hostel - Building 39 (Meyrin site) from 1st February 2013. For more information: https://cds.cern.ch/journal/CERNBulletin/2013/04/Announcements/1505279?ln=en

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...

Implementation of Bridge Management System on Interurban Bridge in Maluku Province

Directory of Open Access Journals (Sweden)

Erwin Marasabessy

2015-05-01

Full Text Available Bridges as transport infrastructures play a vital role in smoothing traffic flows. The success of a bridge in playing its role and serving its function depends on its management. The Directorate General of Highways of the Ministry of Public Work has used a system to manage bridges known as the Bridge Management System (BMS. The system allows a systematic plan and provides a uniform procedure for all bridge operation activities on the national and provincial level. Data from Implementation Agency of National Inter-Urban Roads of Area IX, Northern Maluku in 2011 indicates that the total length of national roads in Maluku Province is 15,238.01 M, with a total of 562 bridges. In Ambon Island, especially, there are 52 bridges totaling 1,176.25 m in length. The study was conducted at several inter-urban bridges in Maluku Province of Ambon Island: Wai Batu Merah, Wai Ruhu, Wai Lawa, Wai Yari and Wai Tua bridges. Assessment of bridge structure conditions was conducted visually to determine the conditions of the existing bridges comprehensively by referring to the Bridge Management System (BMS complemented with a computer-based Bridge Management Information System (BMIS. Condition scores for the five bridges—Wai Batu Merah, Wai Ruhu, Wai Lawa, Wai Yari, and Wai Tua, according to Bridge Management System, are 2, 1, 2, 1, and 2 respectively. The scores of the five bridges indicate that their physical condition can be categorized as good or with minor defects. Based on technical screening, the proposed treatment for Wai Batu Merah, Wai Ruhu, Wai Lawa, dan Wai Tua bridges is the rehabilitation of their sub-elements. As for the Wai Yari Bridge, the treatment will be maintained regularly. The defect repair costs are IDR 149,138,238.00, IDR 81,048,000.00, IDR 174,579,106.10, IDR 79,233,324.01 and IDR 238,323,258.60 for Wai Batu, Wai Ruhu, Wai Lawa, Wai Yari, and Wai Tua Bridges, respectively.

Electrothermally Tunable Bridge Resonator

KAUST Repository

Hajjaj, Amal Z.; Alcheikh, Nouha; Ramini, Abdallah; Hafiz, Md Abdullah Al; Younis, Mohammad I.

2016-01-01

This paper demonstrates experimentally, theoretically, and numerically a wide-range tunability of an in-plane clamped-clamped microbeam, bridge, and resonator compressed by a force due to electrothermal actuation. We demonstrate that a single resonator can be operated at a wide range of frequencies. The microbeam is actuated electrothermally, by passing a DC current through it. We show that when increasing the electrothermal voltage, the compressive stress inside the microbeam increases, which leads eventually to its buckling. Before buckling, the fundamental frequency decreases until it drops to very low values, almost to zero. After buckling, the fundamental frequency increases, which is shown to be as high as twice the original resonance frequency. Analytical results based on the Galerkin discretization of the Euler Bernoulli beam theory are generated and compared to the experimental data and to simulation results of a multi-physics finite-element model. A good agreement is found among all the results.

Electrothermally Tunable Bridge Resonator

KAUST Repository

Hajjaj, Amal Z.

2016-12-05

This paper demonstrates experimentally, theoretically, and numerically a wide-range tunability of an in-plane clamped-clamped microbeam, bridge, and resonator compressed by a force due to electrothermal actuation. We demonstrate that a single resonator can be operated at a wide range of frequencies. The microbeam is actuated electrothermally, by passing a DC current through it. We show that when increasing the electrothermal voltage, the compressive stress inside the microbeam increases, which leads eventually to its buckling. Before buckling, the fundamental frequency decreases until it drops to very low values, almost to zero. After buckling, the fundamental frequency increases, which is shown to be as high as twice the original resonance frequency. Analytical results based on the Galerkin discretization of the Euler Bernoulli beam theory are generated and compared to the experimental data and to simulation results of a multi-physics finite-element model. A good agreement is found among all the results.

WebPASS Explorer (HR Personnel Management)

Data.gov (United States)

US Agency for International Development — WebPass Explorer (WebPASS Framework): USAID is partnering with DoS in the implementation of their WebPass Post Personnel (PS) Module. WebPassPS does not replace...

Structural Dynamic Response Compressing Technique in Bridges using a Cochlea-inspired Artificial Filter Bank (CAFB)

International Nuclear Information System (INIS)

Heo, G; Jeon, J; Son, B; Kim, C; Jeon, S; Lee, C

2016-01-01

In this study, a cochlea-inspired artificial filter bank (CAFB) was developed to efficiently obtain dynamic response of a structure, and a dynamic response measurement of a cable-stayed bridge model was also carried out to evaluate the performance of the developed CAFB. The developed CAFB used a band-pass filter optimizing algorithm (BOA) and peakpicking algorithm (PPA) to select and compress dynamic response signal containing the modal information which was significant enough. The CAFB was then optimized about the El-Centro earthquake wave which was often used in the construction research, and the software implementation of CAFB was finally embedded in the unified structural management system (USMS). For the evaluation of the developed CAFB, a real time dynamic response experiment was performed on a cable-stayed bridge model, and the response of the cable-stayed bridge model was measured using both the traditional wired system and the developed CAFB-based USMS. The experiment results showed that the compressed dynamic response acquired by the CAFB-based USMS matched significantly with that of the traditional wired system while still carrying sufficient modal information of the cable-stayed bridge. (paper)

Long-term bridge performance high priority bridge performance issues.

Science.gov (United States)

2014-10-01

Bridge performance is a multifaceted issue involving performance of materials and protective systems, : performance of individual components of the bridge, and performance of the structural system as a whole. The : Long-Term Bridge Performance (LTBP)...

GPS for structural health monitoring - case study on the Basarab overpass cable-stayed bridge

Science.gov (United States)

Lepadatu, Alexandru; Tiberius, Christian

2014-04-01

The Basarab cable-stayed bridge is a newly built structure in Bucharest, Romania, which was inaugurated in June 2011. Before the oficial opening, in order to assure its qualification for trafic, it had to pass several loading tests with convoys of trucks and trams. For this, besides a priori evaluation using the Finite Element Method (FEM), levelling and acceleration measurements were made to identify vertical displacements, as well as vibration frequencies of the bridge. The three-day loading trial of the bridge represented a good opportunity for setting-up a GPS campaign for structural monitoring of the Basarab bridge. Taking advantage of the redundancy obtained via simultaneous multi-sensor measurements, it was possible to compare and validate the GPS estimated displacements with both FEM and levelling. Moreover, the dynamic behaviour of the bridge during a dynamic loading test was evaluated using a 20 Hz GPS observation rate and validated afterwards with vibration frequency estimates from acceleration time series. Along with simulations (FEM) and laboratory tests, the in situ monitoring of a structure has a particular importance in establishing the safety of a newly-built structure. Furthermore, in some cases permanent monitoring is needed for safety and economic reasons, especially for strategic structures such as dams and bridges. GPS technology can satisfy this request due to its real-time processing capability and thus it can be looked upon as a new and promising tool for dynamic evaluation of engineering structures. In this contribution we have also assessed the performance of GPS with regard to accuracy and false alarm probability demands for the continuous monitoring of the Basarab cable-stayed bridge.

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

Science.gov (United States)

2010-10-01

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

Bridge health monitoring metrics : updating the bridge deficiency algorithm.

Science.gov (United States)

2009-10-01

As part of its bridge management system, the Alabama Department of Transportation (ALDOT) must decide how best to spend its bridge replacement funds. In making these decisions, ALDOT managers currently use a deficiency algorithm to rank bridges that ...

"Which pass is better?" Novel approaches to assess passing effectiveness in elite soccer.

Science.gov (United States)

Rein, Robert; Raabe, Dominik; Memmert, Daniel

2017-10-01

Passing behaviour is a key property of successful performance in team sports. Previous investigations however have mainly focused on notational measurements like total passing frequencies which provide little information about what actually constitutes successful passing behaviour. Consequently, this has hampered the transfer of research findings into applied settings. Here we present two novel approaches to assess passing effectiveness in elite soccer by evaluating their effects on majority situations and space control in front of the goal. Majority situations are assessed by calculating the number of defenders between the ball carrier and the goal. Control of space is estimated using Voronoi-diagrams based on the player's positions on the pitch. Both methods were applied to position data from 103 German First division games from the 2011/2012, 2012/2013 and 2014/2015 seasons using a big data approach. The results show that both measures are significantly related to successful game play with respect to the number of goals scored and to the probability of winning a game. The results further show that on average passes from the mid-field into the attacking area are most effective. The presented passing efficiency measures thereby offer new opportunities for future applications in soccer and other sports disciplines whilst maintaining practical relevance with respect to tactical training regimes or game performances analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

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

Science.gov (United States)

2010-10-01

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

The coma cluster after lunch: Has a galaxcy group passed through the cluster core?

Science.gov (United States)

Burns, Jack O.; Roettiger, Kurt; Ledlow, Michael; Klypin, Anatoly

1994-01-01

We propose that the Coma cluster has recently undergone a collision with the NGC 4839 galaxy group. The ROSAT X-ray morphology, the Coma radio halo, the presence of poststarburst galaxies in the bridge between Coma and NGC 4839, the usually high velocity dispersion for the NGC 4839 group, and the position of a large-scale galaxy filament to the NE of Coma are all used to argue that the NGC 4839 group passed through the core of Coma approximately 2 Gyr ago. We present a new Hydro/N-body simulation of the merger between a galaxy group and a rich cluster that reproduces many of the observed X-ray and optical properties of Coma/NGC 4839.

Observations on the bony bridging of the jugular foramen in man.

Science.gov (United States)

Dodo, Y

1986-02-01

The anatomical nature and pattern of incidence of bony bridging of the jugular foramen was investigated using 64 fetal crania aged nine months to term and 222 adult crania of Japanese. In addition, the region of the jugular foramen of an adult cadaver was carefully dissected in order to clarify the relationship between the cranial nerves passing through the jugular foramen and the intrajugular processes of the jugular foramen. The general conclusions concerning the anatomical nature of the bony bridging of the jugular foramen were as follows. (1) The intrajugular process of the temporal bone is situated posterior to the triangular depression (as described in Gray's Anatomy) of the petrous part. (2) The bony bridging of the jugular foramen is established by the contact of the intrajugular process of the temporal bone with the bony process of the occipital bone projecting either from just above the hypoglossal canal (Type I) or from posterior to the hypoglossal canal (Type III). (3) If both the processes of the occipital bone reach the intrajugular process of the temporal bone simultaneously, the jugular foramen is divided into three compartments. (4) In the case of Type I bridging, the anteromedial compartment transmits the glossopharyngeal nerve, while the posterolateral compartment gives passage to the vagus nerve, the accessory nerve and the internal jugular vein. (5) In the case of Type II bridging, the anteromedial compartment contains the glossopharyngeal, vagus and accessory nerves, and the posterolateral compartment transmits the internal jugular vein. (6) When tripartite division of the jugular foramen occurs, the anteromedial compartment transmits the glossopharyngeal nerve, the middle compartment contains the vagus and accessory nerves, and the posterolateral compartment transmits the internal jugular vein. Concerning the pattern of incidence of jugular foramen bridging in the Japanese fetal and adult cranial series, this is similar to that of the bony

Field performance of timber bridges. 7, Connell Lake stress-laminated deck bridge

Science.gov (United States)

L. E. Hislop; M. A. Ritter

The Connell Lake bridge was constructed in early 1991 on the Tongass National Forest, Alaska, as a demonstration bridge under the Timber Bridge Initiative. The bridge is a stress-laminated deck structure with an approximate 36-ft length and 18-ft width and is the first known stress-laminated timber bridge constructed in Alaska. Performance of the bridge was monitored...

Track-Bridge Longitudinal Interaction of Continuous Welded Rails on Arch Bridge

Directory of Open Access Journals (Sweden)

Rong Chen

2013-01-01

Full Text Available Taking arch bridges, including deck, half-through, and through arch bridges (short for DAB, HTAB, and TAB as examples, mechanics analysis models of longitudinal interaction between continuously welded rails (short for CWRs and arch bridges are established. Based on the finite element method (FEM, the longitudinal interaction calculation software of CWR on arch bridges has been developed. Focusing on an HTAB, the tension, compression, and deflection conditions are calculated and analyzed. The results show that the mechanics analysis models of three types of arch bridges can truly reflect the real state of the structure; the calculation software can be used for systematic research of the CWR on arch bridge; as for HTAB, temperature difference of arch rib has a small effect on rail tension/compression, and arch bridge can be simplified as a continuous beam for rail tension/compression additional force calculation; in calculation of deflection conditions of HTAB, it is suggested that train loads are arranged on half span and full span and take the direction of load entering bridge into account. Additionally, the deflection additional force variation of CFST basket handle arch bridge is different from that of ordinary bridge.

Bridges

NARCIS (Netherlands)

Zant, W.

2017-01-01

We estimate to what extent bridges in Mozambique lead to transport cost reductions and attribute these reductions to key determinants, in particular road distance, road quality and crossing borders. For identification we exploit the introduction of a road bridge over the Zambezi river, in August

Field performance of timber bridges. 4, Graves Crossing stress-laminated deck bridge

Science.gov (United States)

J. P. Wacker; M. A. Ritter

The Graves Crossing bridge was constructed October 1991 in Antrim County, Michigan, as part of the demonstration timber bridge program sponsored by the USDA Forest Service. The bridge is a two-span continuous, stress-laminated deck superstructure and it is 36-ft long and 26-ft wide. The bridge is one of the first stress-laminated deck bridges to be built of sawn lumber...

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.

The hepatic bridge.

Science.gov (United States)

Sugarbaker, Paul H

2018-07-01

The hepatic bridge forms a tunnel of liver parenchyma that may obscure peritoneal metastases associated with the round ligament. Visualization and then resection of nodules associated with this structure is necessary. The incidence of a hepatic bridge and the extent that it covered the round ligament was determined in consecutive patients. Extent of coverage of the round ligament by the hepatic bridge was determined: Class 1 indicates up to one-third of the round ligament obscured, Class 2 up to two-thirds and Class 3 more than two-thirds. In 102 patients in whom the round ligament of the liver could be completely visualized, 50 had a hepatic bridge. Class 1 was 22 (44%) of the bridges, Class 2 was 16 (32%) and Class 3 was 12 (24%). A hepatic bridge was more frequently present in 28 of 45 male patients (62%) vs. 22 of 57 female patients (38%). Approximately one-half of our patients having cytoreductive surgery for peritoneal metastases were observed to have a hepatic bridge. Up to 56% of these patients have Class 2 or 3 hepatic bridge and may require division of the hepatic bridge to completely visualize the contents of the tunnel created by this structure. Copyright © 2018 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

Bridge resource program.

Science.gov (United States)

2013-09-01

The mission of Rutgers Universitys Center for Advanced Infrastructure and Transportation (CAIT) Bridge Resource Program (BRP) is to provide bridge engineering support to the New Jersey Department of Transportation (NJDOT)s Bridge Engineering an...

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.

Laboratory and field testing of an accelerated bridge construction demonstration bridge : US Highway 6 bridge over Keg Creek.

Science.gov (United States)

2013-04-01

The US Highway 6 Bridge over Keg Creek outside of Council Bluffs, Iowa is a demonstration bridge site chosen to put into practice : newly-developed Accelerated Bridge Construction (ABC) concepts. One of these new concepts is the use of prefabricated ...

Guardrails for Use on Historic Bridges: Volume 2—Bridge Deck Overhang Design

OpenAIRE

Frosch, Robert J.; Morel, Adam J.

2016-01-01

Bridges that are designated historic present a special challenge to bridge engineers whenever rehabilitation work or improvements are made to the bridges. Federal and state laws protect historically significant bridges, and railings on these bridges can be subject to protection because of the role they play in aesthetics. Unfortunately, original railings on historic bridges do not typically meet current crash-test requirements and typically do not meet current standards for railing height and...

[Artificial Cysteine Bridges on the Surface of Green Fluorescent Protein Affect Hydration of Its Transition and Intermediate States].

Science.gov (United States)

Melnik, T N; Nagibina, G S; Surin, A K; Glukhova, K A; Melnik, B S

2018-01-01

Studying the effect of cysteine bridges on different energy levels of multistage folding proteins will enable a better understanding of the process of folding and functioning of globular proteins. In particular, it will create prospects for directed change in the stability and rate of protein folding. In this work, using the method of differential scanning microcalorimetry, we have studied the effect of three cysteine bridges introduced in different structural elements of the green fluorescent protein on the denaturation enthalpies, activation energies, and heat-capacity increments when this protein passes from native to intermediate and transition states. The studies have allowed us to confirm that, with this protein denaturation, the process hardly damages the structure initially, but then changes occur in the protein structure in the region of 4-6 beta sheets. The cysteine bridge introduced in this region decreases the hydration of the second transition state and increases the hydration of the second intermediate state during the thermal denaturation of the green fluorescent protein.

DYNAMIC BEHAVIOR OF TWO-SPAN CONTINUOUS CONCRETE BRIDGES UNDER MOVING OF HIGH-SPEED TRAINS

Directory of Open Access Journals (Sweden)

O. H. Marinichenko

2017-10-01

Full Text Available Purpose. The scientific work provides a comparison of the results of the movement of a high-speed passenger train across the bridge, obtained as a result of finite element modeling in the SAP2000 software package, and real tests of a double-span concrete railway bridge. Analysis of the rigid characteristics of flying structures. Methodology.The numerical method presented in this study shows valid results concerning the dynamic analysis of the behavior of bridges in conditions of high-speed train traffic. The factors influencing the dynamic behavior of bridges under moving loads, the influence of design parameters and rolling stock, as well as the interaction of the train and spans are determined. The system was used in the form of moving concentrated forces simulating the axes of the train. Findings. Maximum movements and accelerations were obtained as a result of the dynamic calculation for different speeds of the train and compared with practical tests. The correctness of the model of a span structure with regard to continuous ferroconcrete spans was verified. Originality. Within the framework of the work, the latest test results were used, including those with speeds calculated on the prospect of rail passenger traffic. For these tests, a model of a span structure was developed. Practical value. The results of the research can be used to plan the introduction of high-speed train traffic on existing and planned flying structures of reinforced concrete bridges. An approach to the design of span structures that will be effective when passing high-speed passenger trains is implemented.

Dynamic assessment of bridge deck performance considering realistic bridge-traffic interaction

Science.gov (United States)

2017-09-01

Concrete bridge decks are directly exposed to daily traffic loads and may experience some surface cracking caused by excessive stress or fatigue accumulation, which requires repair or replacement. Among typical bridges in North America, bridge decks ...

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....

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

Science.gov (United States)

Taylor, J. L.; Harmon, T.

2010-01-01

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

Field performance of timber bridges. 6, Hoffman Run stress-laminated deck bridge

Science.gov (United States)

M. A. Ritter; P. D. Hilbrich Lee; G. J. Porter

The Hoffman Run bridge, located just outside Dahoga, Pennsylvania, was constructed in October 1990. The bridge is a simple-span, single-lane, stress-laminated deck superstructure that is approximately 26 ft long and 16 ft wide. It is the second stress-laminated timber bridge to be constructed of hardwood lumber in Pennsylvania. The performance of the bridge was...

The hidden costs: Identification of indirect costs associated with acute gastrointestinal illness in an Inuit community

Science.gov (United States)

Vriezen, Rachael; Edge, Victoria L.; Ford, James; Wood, Michele; Harper, Sherilee

2018-01-01

Background Acute gastrointestinal illness (AGI) incidence and per-capita healthcare expenditures are higher in some Inuit communities as compared to elsewhere in Canada. Consequently, there is a demand for strategies that will reduce the individual-level costs of AGI; this will require a comprehensive understanding of the economic costs of AGI. However, given Inuit communities’ unique cultural, economic, and geographic contexts, there is a knowledge gap regarding the context-specific indirect costs of AGI borne by Inuit community members. This study aimed to identify the major indirect costs of AGI, and explore factors associated with these indirect costs, in the Inuit community of Rigolet, Canada, in order to develop a case-based context-specific study framework that can be used to evaluate these costs. Methods A mixed methods study design and community-based methods were used. Qualitative in-depth, group, and case interviews were analyzed using thematic analysis to identify and describe indirect costs of AGI specific to Rigolet. Data from two quantitative cross-sectional retrospective surveys were analyzed using univariable regression models to examine potential associations between predictor variables and the indirect costs. Results/Significance The most notable indirect costs of AGI that should be incorporated into cost-of-illness evaluations were the tangible costs related to missing paid employment and subsistence activities, as well as the intangible costs associated with missing community and cultural events. Seasonal cost variations should also be considered. This study was intended to inform cost-of-illness studies conducted in Rigolet and other similar research settings. These results contribute to a better understanding of the economic impacts of AGI on Rigolet residents, which could be used to help identify priority areas and resource allocation for public health policies and programs. PMID:29768456

Photoacoustic Soot Spectrometer (PASS) Instrument Handbook

Energy Technology Data Exchange (ETDEWEB)

Dubey, M [Los Alamos National Laboratory; Springston, S [Brookhaven National Laboratory; Koontz, A [Pacific Northwest National Laboratory; Aiken, A [Los Alamos National Laboratory

2013-01-17

The photoacoustic soot spectrometer (PASS) measures light absorption by aerosol particles. As the particles pass through a laser beam, the absorbed energy heats the particles and in turn the surrounding air, which sets off a pressure wave that can be detected by a microphone. The PASS instruments deployed by ARM can also simultaneously measure the scattered laser light at three wavelengths and therefore provide a direct measure of the single-scattering albedo. The Operator Manual for the PASS-3100 is included here with the permission of Droplet Measurement Technologies, the instrument’s manufacturer.

Drill pipe bridge plug

International Nuclear Information System (INIS)

Winslow, D.W.; Brisco, D.P.

1991-01-01

This patent describes a method of stopping flow of fluid up through a pipe bore of a pipe string in a well. It comprises: lowering a bridge plug apparatus on a work string into the pipe string to a position where the pipe bore is to be closed; communicating the pipe bore below a packer of the bridge plug apparatus through the bridge plug apparatus with a low pressure zone above the packer to permit the fluid to flow up through the bridge plug apparatus; engaging the bridge plug apparatus with an internal upset of the pipe string; while the fluid is flowing up through the bridge plug apparatus, pulling upward on the work string and the bridge plug apparatus and thereby sealing the packer against the pipe bore; isolating the pipe bore below the packer from the low pressure zone above the packer and thereby stopping flow of the fluid up through the pipe bore; disconnecting the work string from the bridge plug apparatus; and maintaining the bridge plug apparatus in engagement with the internal upset and sealed against the pipe bore due to an upward pressure differential applied to the bridge plug apparatus by the fluid contained therebelow

77 FR 51470 - Drawbridge Operation Regulations; Gulf Intracoastal Waterway, St. Petersburg/Tampa, FL

Science.gov (United States)

2012-08-24

... Bridge; the Pinellas Bayway Structure ``C'' (SR 679) Bridge; and Johns Pass Bridge. DATES: These.... Secret Service, Federal Bureau of Investigation, Customs and Border Protection, U.S. Coast Guard, and the... Structure ``C'' (SR 679) Bridge; and Johns Pass Bridge across Johns Pass, Madeira Beach, Florida. These...

Bridging Anticoagulation

Science.gov (United States)

... clinical centers in the United States, Canada, and Brazil. A more detailed description of the study is ... Your Personal Message Send Message Share on Social Media Bridging Anticoagulation The BRIDGE Study Investigators Circulation. 2012; ...

Bridging the Gap

DEFF Research Database (Denmark)

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

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

Long Span Bridges in Scandinavia

DEFF Research Database (Denmark)

Gimsing, Niels Jørgen

1998-01-01

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

Integral Abutment and Jointless Bridges

Directory of Open Access Journals (Sweden)

Cristian-Claudiu Comisu

2005-01-01

Full Text Available 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 that have their superstructure cast integrally with their substructure. The jointless bridges cost less to construct and require less maintenance then equivalent bridges with expansion joints. Integral bridges present a challenge for load distribution calculations because the bridge deck, piers, abutments, embankments and soil must all be considered as single compliant system. This paper presents some of the important features of integral abutment and jointless bridge design and some guidelines to achieve improved design. The goal of this paper is to enhance the awareness among the engineering community to use integral abutment and jointless bridges in Romania.

Bridge deterioration models to support Indiana's bridge management system.

Science.gov (United States)

2016-02-01

An effective bridge management system that is equipped with reliable deterioration models enables agency engineers to carry out : monitoring and long-term programming of bridge repair actions. At the project level, deterioration models help the agenc...

Automatic Bridge Control System

OpenAIRE

M. Niraimathi; S.Sivakumar; R.Vigneshwaran; R.Vinothkumar; P.Babu

2012-01-01

Bridge vibration control is an important issue whose purpose is to extend the structural service life of bridges. Normally, the bridge is modeled as an elastic beam or plate subject to a moving vehicle. However, the moving truck on a bridge is a complicated problem that must still be researched. In this paper, wepropose a new method, to overcome the huge load in the bridge a load cell is used at the entry which will monitor the load continuously at both ends. To escape from the heavy water fl...

Fabrication of seamless calandria tubes by cold pilgering route using 3-pass and 2-pass schedules

Science.gov (United States)

Saibaba, N.

2008-12-01

Calandria tube is a large diameter, extremely thin walled zirconium alloy tube which has diameter to wall thickness ratio as high as 90-95. Such tubes are conventionally produced by the 'welded route', which involves extrusion of slabs followed by a series of hot and cold rolling passes, intermediate anneals, press forming of sheets into circular shape and closing the gap by TIG welding. Though pilgering is a well established process for the fabrication of seamless tubes, production of extremely thin walled tubes offers several challenges during pilgering. Nuclear fuel complex (NFC), Hyderabad, has successfully developed a process for the production of Zircaloy-4 calandria tubes by adopting the 'seamless route' which involves hot extrusion of mother blanks followed by three-pass pilgering or two-pass pilgering schedules. This paper deals with standardization of the seamless route processes for fabrication of calandria tubes, comparison between the tubes produced by 2-pass and 3-pass pilgering schedules, role of ultrasonic test charts for control of process parameters, development of new testing methods for burst testing and other properties.

Fabrication of seamless calandria tubes by cold pilgering route using 3-pass and 2-pass schedules

International Nuclear Information System (INIS)

Saibaba, N.

2008-01-01

Calandria tube is a large diameter, extremely thin walled zirconium alloy tube which has diameter to wall thickness ratio as high as 90-95. Such tubes are conventionally produced by the 'welded route', which involves extrusion of slabs followed by a series of hot and cold rolling passes, intermediate anneals, press forming of sheets into circular shape and closing the gap by TIG welding. Though pilgering is a well established process for the fabrication of seamless tubes, production of extremely thin walled tubes offers several challenges during pilgering. Nuclear fuel complex (NFC), Hyderabad, has successfully developed a process for the production of Zircaloy-4 calandria tubes by adopting the 'seamless route' which involves hot extrusion of mother blanks followed by three-pass pilgering or two-pass pilgering schedules. This paper deals with standardization of the seamless route processes for fabrication of calandria tubes, comparison between the tubes produced by 2-pass and 3-pass pilgering schedules, role of ultrasonic test charts for control of process parameters, development of new testing methods for burst testing and other properties

Existing Steel Railway Bridges Evaluation

Science.gov (United States)

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

2016-12-01

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

Possibilities of the fish pass restoration

Science.gov (United States)

Čubanová, Lea

2018-03-01

According to the new elaborated methodology of the Ministry of Environment of the Slovak Republic: Identification of the appropriate fish pass types according to water body typology (2015) each barrier on the river must be passable. On the barriers or structures without fish passes new ones should be design and built and on some water structures with existed but nonfunctional fish passes must be realized reconstruction or restoration of such objects. Assessment should be done in terms of the existing migratory fish fauna and hydraulic conditions. Fish fauna requirements resulting from the ichthyological research of the river section with barrier. Hydraulic conditions must than fulfil these requirements inside the fish pass body.

Field performance of timber bridges. 5, Little Salmon Creek stress-laminated deck bridge

Science.gov (United States)

M. A. Ritter; J. A. Kainz; G. J. Porter

The Little Salmon Creek bridge was constructed in November 1988 on the Allegheny National Forest in Pennsylvania. The bridge is a simple span, single-lane, stress-laminated deck superstructure that is approximately 26-ft long and 16-ft wide. The bridge is unique in that it is the first known stress-laminated timber bridge to be constructed of hardwood lumber. The...

Field performance of timber bridges. 9, Big Erick`s stress-laminated deck bridge

Science.gov (United States)

J. A. Kainz; J. P. Wacker; M. Nelson

The Big Erickas bridge was constructed during September 1992 in Baraga County, Michigan. The bridge is 72 ft long, 16 ft wide, and consists of three simple spans: two stress-laminated deck approach spans and a stress-laminated box center span. The bridge is unique in that it is one of the first known stress-laminated timber bridge applications to use Eastern Hemlock...

Existing Steel Railway Bridges Evaluation

Directory of Open Access Journals (Sweden)

Vičan Josef

2016-12-01

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

Light-weight aluminium bridges and bridge decks. An overview of recent applications

NARCIS (Netherlands)

Maljaars, J.; Soetens, F.; Kluyver, D. de

2008-01-01

The last decades have shown a large increase in the application of aluminium alloys for light-weight bridges. For bridge construction, aluminium alloys have some specific advantages, but also some points of attention. This paper deals with some recent projects of aluminium bridges, and for these

WebPASS ICASS (HR Personnel Management)

Data.gov (United States)

US Agency for International Development — WebPASS Joint Administrative Support Platforms Post Administrative Software Suite - U.S. Department of State Executive Officers application suite. Web.PASS is the...

An experimental evaluation of multi-pass solar air heaters

Energy Technology Data Exchange (ETDEWEB)

Satcunanathan, S.; Persad, P.

1980-12-01

Three collectors of identical dimensions but operating in the single-pass, two-pass and three-pass modes were tested simultaneously under ambient conditions. It was found that the two-pass air heater was consistently better than the single-pass air heater over the day for the range of mass flow rates considered. It was also found that at a mass flow rate of 0.0095 kg s/sup -1/ m/sup -2/, the thermal performances of the two-pass and three-pass collectors were identical, but at higher flow rates the two-pass collector was superior to the three-pass collector, the superiority decreasing with increasing mass flow rate.

Development of bridge girder movement criteria for accelerated bridge construction.

Science.gov (United States)

2014-06-01

End diaphragms connect multiple girders to form a bridge superstructure system for effective resistance to earthquake loads. Concrete : girder bridges that include end diaphragms consistently proved to perform well during previous earthquake events. ...

Message passing for quantified Boolean formulas

International Nuclear Information System (INIS)

Zhang, Pan; Ramezanpour, Abolfazl; Zecchina, Riccardo; Zdeborová, Lenka

2012-01-01

We introduce two types of message passing algorithms for quantified Boolean formulas (QBF). The first type is a message passing based heuristics that can prove unsatisfiability of the QBF by assigning the universal variables in such a way that the remaining formula is unsatisfiable. In the second type, we use message passing to guide branching heuristics of a Davis–Putnam–Logemann–Loveland (DPLL) complete solver. Numerical experiments show that on random QBFs our branching heuristics give robust exponential efficiency gain with respect to state-of-the-art solvers. We also manage to solve some previously unsolved benchmarks from the QBFLIB library. Apart from this, our study sheds light on using message passing in small systems and as subroutines in complete solvers

A floating bridge disrupts seaward migration and increases mortality of steelhead smolts in Hood Canal, Washington state.

Directory of Open Access Journals (Sweden)

Megan Moore

Full Text Available Habitat modifications resulting from human transportation and power-generation infrastructure (e.g., roads, dams, bridges can impede movement and alter natural migration patterns of aquatic animal populations, which may negatively affect survival and population viability. Full or partial barriers are especially problematic for migratory species whose life histories hinge on habitat connectivity.The Hood Canal Bridge, a floating structure spanning the northern outlet of Hood Canal in Puget Sound, Washington, extends 3.6 meters underwater and forms a partial barrier for steelhead migrating from Hood Canal to the Pacific Ocean. We used acoustic telemetry to monitor migration behavior and mortality of steelhead smolts passing four receiver arrays and several single receivers within the Hood Canal, Puget Sound, and Strait of Juan de Fuca. Twenty-seven mortality events were detected within the vicinity of the Hood Canal Bridge, while only one mortality was recorded on the other 325 receivers deployed throughout the study area. Migrating steelhead smolts were detected at the Hood Canal Bridge array with greater frequency, on more receivers, and for longer durations than smolts migrating past three comparably configured arrays. Longer migration times and paths are likely to result in a higher density of smolts near the bridge in relation to other sites along the migration route, possibly inducing an aggregative predator response to steelhead smolts.This study provides strong evidence of substantial migration interference and increased mortality risk associated with the Hood Canal Bridge, and may partially explain low early marine survival rates observed in Hood Canal steelhead populations. Understanding where habitat modifications indirectly increase predation pressures on threatened populations helps inform potential approaches to mitigation.

A floating bridge disrupts seaward migration and increases mortality of steelhead smolts in Hood Canal, Washington state.

Science.gov (United States)

Moore, Megan; Berejikian, Barry A; Tezak, Eugene P

2013-01-01

Habitat modifications resulting from human transportation and power-generation infrastructure (e.g., roads, dams, bridges) can impede movement and alter natural migration patterns of aquatic animal populations, which may negatively affect survival and population viability. Full or partial barriers are especially problematic for migratory species whose life histories hinge on habitat connectivity. The Hood Canal Bridge, a floating structure spanning the northern outlet of Hood Canal in Puget Sound, Washington, extends 3.6 meters underwater and forms a partial barrier for steelhead migrating from Hood Canal to the Pacific Ocean. We used acoustic telemetry to monitor migration behavior and mortality of steelhead smolts passing four receiver arrays and several single receivers within the Hood Canal, Puget Sound, and Strait of Juan de Fuca. Twenty-seven mortality events were detected within the vicinity of the Hood Canal Bridge, while only one mortality was recorded on the other 325 receivers deployed throughout the study area. Migrating steelhead smolts were detected at the Hood Canal Bridge array with greater frequency, on more receivers, and for longer durations than smolts migrating past three comparably configured arrays. Longer migration times and paths are likely to result in a higher density of smolts near the bridge in relation to other sites along the migration route, possibly inducing an aggregative predator response to steelhead smolts. This study provides strong evidence of substantial migration interference and increased mortality risk associated with the Hood Canal Bridge, and may partially explain low early marine survival rates observed in Hood Canal steelhead populations. Understanding where habitat modifications indirectly increase predation pressures on threatened populations helps inform potential approaches to mitigation.

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...

Oil price pass-through into inflation

International Nuclear Information System (INIS)

Chen, Shiu-Sheng

2009-01-01

This paper uses data from 19 industrialized countries to investigate oil price pass-through into inflation across countries and over time. A time-varying pass-through coefficient is estimated and the determinants of the recent declining effects of oil shocks on inflation are investigated. The appreciation of the domestic currency, a more active monetary policy in response to inflation, and a higher degree of trade openness are found to explain the decline in oil price pass-through. (author)

Field performance of timber bridges. 17, Ciphers stress-laminated deck bridge

Science.gov (United States)

James P. Wacker; James A. Kainz; Michael A. Ritter

In September 1989, the Ciphers bridge was constructed within the Beltrami Island State Forest in Roseau County, Minnesota. The bridge superstructure is a two-span continuous stress-laminated deck that is approximately 12.19 m long, 5.49 m wide, and 305 mm deep (40 ft long, 18 ft wide, and 12 in. deep). The bridge is one of the first to utilize red pine sawn lumber for...

Remarks on crack-bridging concepts

International Nuclear Information System (INIS)

Bao, G.; Suo, Z.

1992-01-01

The article draws upon recent work by us and our colleagues on metal and ceramic matrix composites for high temperature engines. The central theme here is to deduce mechanical properties, such as toughness, strength and notch-ductility, from bridging laws that characterize inelastic processes associated with fracture. A particular set of normalization is introduced to present the design charts, segregating the roles played by the shape, and the scale, of a bridging law. A single material length, γ 0 E/σ 0 , emerges, where γ 0 is the limiting-separation, σ 0 the bridging-strength, and E the Young's modulus of the solid. It is the huge variation of this length-from a few manometers for atomic bond, to a meter for cross-over fibers - that underlies the richness in material behaviors. Under small-scale bridging conditions, γ 0 E/σ 0 is the only basic length scale in the mechanics problem and represents, with a pre-factor about 0.4, the bridging zone size. A catalog of small-scale bridging solutions is compiled for idealized bridging laws. Large-scale bridging introduces a dimensionless group, a/(γ 0 E/σ 0 ), where a is a length characterizing the component. The group plays a major role in all phenomena associated with bridging, and provides a focus of discussion in this article. For example, it quantifies the bridging scale when a is the unbridged crack length, and notch-sensitivity when a is hole radius. The difference and the connection between Irwin's fracture mechanics and crack bridging concepts are discussed. It is demonstrated that fracture toughness and resistance curve are meaningful only when small-scale bridging conditions prevail, and therefore of limited use in design with composites. Many other mechanical properties of composites, such as strength and notch-sensitivity, can be simulated by invoking large-scale bridging concepts. 37 refs., 21 figs., 3 tabs

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

Science.gov (United States)

2010-10-01

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

Cooperativity of complex salt bridges

OpenAIRE

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

2008-01-01

The energetic contribution of complex salt bridges, in which one charged residue (anchor residue) forms salt bridges with two or more residues simultaneously, has been suggested to have importance for protein stability. Detailed analysis of the net energetics of complex salt bridge formation using double- and triple-mutant cycle analysis revealed conflicting results. In two cases, it was shown that complex salt bridge formation is cooperative, i.e., the net strength of the complex salt bridge...

Implementing statistical analysis in multi-channel acoustic impact-echo testing of concrete bridge decks: Determining thresholds for delamination detection

Science.gov (United States)

Hendricks, Lorin; Spencer Guthrie, W.; Mazzeo, Brian

2018-04-01

An automated acoustic impact-echo testing device with seven channels has been developed for faster surveying of bridge decks. Due to potential variations in bridge deck overlay thickness, varying conditions between testing passes, and occasional imprecise equipment calibrations, a method that can account for variations in deck properties and testing conditions was necessary to correctly interpret the acoustic data. A new methodology involving statistical analyses was therefore developed. After acoustic impact-echo data are collected and analyzed, the results are normalized by the median for each channel, a Gaussian distribution is fit to the histogram of the data, and the Kullback-Leibler divergence test or Otsu's method is then used to determine the optimum threshold for differentiating between intact and delaminated concrete. The new methodology was successfully applied to individual channels of previously unusable acoustic impact-echo data obtained from a three-lane interstate bridge deck surfaced with a polymer overlay, and the resulting delamination map compared very favorably with the results of a manual deck sounding survey.

Comprehensive evaluation of fracture critical bridges.

Science.gov (United States)

2014-02-01

Two-girder steel bridges are classified as fracture critical bridges based on the definition given in the AASHTO LRFD Bridge Design Specifications. In a fracture critical bridge a failure of a tension member leads to collapse of the bridge. However, ...

Timber in Bridge Structures

OpenAIRE

Detkin, Viktoria

2016-01-01

The purpose of this final year project was to study the properties of timber as a structural material and the suitability of wood in load bearing members for bridge structures. For a case study, an existing timber bridge was selected. Due to its condition the bridge should be replaced. The design of a new bridge with steel beams holding a glulam deck was made. During the case study the replacement of steel beams by glulam timber ones was discussed. Some calculations were made in order to ...

Field performance of timber bridges. 16, North Siwell Road stress-laminated bridge

Science.gov (United States)

J. A. Kainz

The North Siwell Road bridge was constructed during December 1994 in Hinds County, Mississippi. The bridge is a single-span, stress-laminated T-beam structure that measures 9.1 m (30 ft) long and 8.7 m (28.5 ft) wide. Performance of the bridge was monitored for 24 months, beginning at the time of installation. Monitoring involved gathering and evaluating data relative...

Field performance of timber bridges. 10, Sanborn Brook stress-laminated deck bridge

Science.gov (United States)

P. D. Hilbrich Lee; J. P. Wacker; M. A. Ritter

The Sanborn Brook bridge was constructed in August 1991, 10 miles northeast of Concord, New Hampshire, as part of the demonstration timber bridge program of the USDA Forest Service. The bridge is a simple-span, double-lane, stress-laminated deck superstructure constructed from Southern Pine lumber and is approximately 25 ft long and 28 ft wide with a skew of 14 degrees...

Simulation of multivariate diffusion bridges

DEFF Research Database (Denmark)

Bladt, Mogens; Finch, Samuel; Sørensen, Michael

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

Steel-soil composite bridge

DEFF Research Database (Denmark)

Du, Guangli; Pettersson, Lars; Karoumi, Raid

2017-01-01

viability, while their environmental performance is overlooked. Today’s designers are urged to seek new design options to reduce the environmental burdens. Sweden owns more than 24574 bridges and most of them are short spans. Among them, the slab frame bridge (CFB) is a common solution. Soil steel composite...... bridge (SSCB), alternatively, is a functionally equivalent solution to CFB and shows advantages in low cost and easy construction. This paper compares the environmental performance between these two bridge types based on life cycle assessment (LCA). The analysis and result shows that, the SSCB...

Building water bridges in air: Electrohydrodynamics of the floating water bridge

Science.gov (United States)

Marín, Álvaro G.; Lohse, Detlef

2010-12-01

The interaction of electrical fields and liquids can lead to a phenomenon that defies intuition. Some famous examples can be found in electrohydrodynamics as Taylor cones, whipping jets, or noncoalescing drops. A less famous example is the floating water bridge: a slender thread of water held between two glass beakers in which a high voltage difference is applied. Surprisingly, the water bridge defies gravity even when the beakers are separated at distances up to 2 cm. In this paper, experimental measurements and simple models are proposed and discussed for the stability of the bridge and the source of the flow, revealing an important role of polarization forces on the stability of the water bridge. On the other hand, the observed flow can only be explained due to the non-negligible free charge present in the surface. In this sense, the floating water bridge can be considered as an extreme case of a leaky dielectric liquid [J. R. Melcher and G. I. Taylor, Annu. Rev. Fluid Mech. 1, 111 (1969)].

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,...

Nanomechanical characterization by double-pass force-distance mapping

Energy Technology Data Exchange (ETDEWEB)

Dagdas, Yavuz S; Tekinay, Ayse B; Guler, Mustafa O; Dana, Aykutlu [UNAM Institute of Materials Science and Nanotechnology, Bilkent University, 06800 Ankara (Turkey); Necip Aslan, M, E-mail: aykutlu@unam.bilkent.edu.tr [Department of Physics, Istanbul Technical University, Istanbul (Turkey)

2011-07-22

We demonstrate high speed force-distance mapping using a double-pass scheme. The topography is measured in tapping mode in the first pass and this information is used in the second pass to move the tip over the sample. In the second pass, the cantilever dither signal is turned off and the sample is vibrated. Rapid (few kHz frequency) force-distance curves can be recorded with small peak interaction force, and can be processed into an image. Such a double-pass measurement eliminates the need for feedback during force-distance measurements. The method is demonstrated on self-assembled peptidic nanofibers.

Nanomechanical characterization by double-pass force-distance mapping

International Nuclear Information System (INIS)

Dagdas, Yavuz S; Tekinay, Ayse B; Guler, Mustafa O; Dana, Aykutlu; Necip Aslan, M

2011-01-01

We demonstrate high speed force-distance mapping using a double-pass scheme. The topography is measured in tapping mode in the first pass and this information is used in the second pass to move the tip over the sample. In the second pass, the cantilever dither signal is turned off and the sample is vibrated. Rapid (few kHz frequency) force-distance curves can be recorded with small peak interaction force, and can be processed into an image. Such a double-pass measurement eliminates the need for feedback during force-distance measurements. The method is demonstrated on self-assembled peptidic nanofibers.

Wright-Fisher diffusion bridges.

Science.gov (United States)

Griffiths, Robert C; Jenkins, Paul A; Spanò, Dario

2017-10-06

The trajectory of the frequency of an allele which begins at x at time 0 and is known to have frequency z at time T can be modelled by the bridge process of the Wright-Fisher diffusion. Bridges when x=z=0 are particularly interesting because they model the trajectory of the frequency of an allele which appears at a time, then is lost by random drift or mutation after a time T. The coalescent genealogy back in time of a population in a neutral Wright-Fisher diffusion process is well understood. In this paper we obtain a new interpretation of the coalescent genealogy of the population in a bridge from a time t∈(0,T). In a bridge with allele frequencies of 0 at times 0 and T the coalescence structure is that the population coalesces in two directions from t to 0 and t to T such that there is just one lineage of the allele under consideration at times 0 and T. The genealogy in Wright-Fisher diffusion bridges with selection is more complex than in the neutral model, but still with the property of the population branching and coalescing in two directions from time t∈(0,T). The density of the frequency of an allele at time t is expressed in a way that shows coalescence in the two directions. A new algorithm for exact simulation of a neutral Wright-Fisher bridge is derived. This follows from knowing the density of the frequency in a bridge and exact simulation from the Wright-Fisher diffusion. The genealogy of the neutral Wright-Fisher bridge is also modelled by branching Pólya urns, extending a representation in a Wright-Fisher diffusion. This is a new very interesting representation that relates Wright-Fisher bridges to classical urn models in a Bayesian setting. Copyright © 2017 Elsevier Inc. All rights reserved.

National Bridge Inventory System (NBI)

Data.gov (United States)

Department of Transportation — The NBI System is the collection of bridge inspection information and costs associated with bridge replacements of structurally deficient bridges on and off the NHS....

Extracorporeal Life Support Bridge to Ventricular Assist Device: The Double Bridge Strategy.

Science.gov (United States)

Marasco, Silvana F; Lo, Casey; Murphy, Deirdre; Summerhayes, Robyn; Quayle, Margaret; Zimmet, Adam; Bailey, Michael

2016-01-01

In patients requiring left ventricular assist device (LVAD) support, it can be difficult to ascertain suitability for long-term mechanical support with LVAD and eventual transplantation. LVAD implantation in a shocked patient is associated with increased morbidity and mortality. Interest is growing in the utilization of extracorporeal life support (ECLS) as a bridge-to-bridge support for these critically unwell patients. Here, we reviewed our experience with ECLS double bridging. We hypothesized that ECLS double bridging would stabilize end-organ dysfunction and reduce ventricular assist device (VAD) implant perioperative mortality. We conducted a retrospective review of prospectively collected data for 58 consecutive patients implanted with a continuous-flow LVAD between January 2010 and December 2013 at The Alfred Hospital, Melbourne, Victoria, Australia. Twenty-three patients required ECLS support pre-LVAD while 35 patients underwent LVAD implantation without an ECLS bridge. Preoperative morbidity in the ECLS bridge group was reflected by increased postoperative intensive care duration, blood loss, blood product use, and postoperative renal failure, but without negative impact upon survival when compared with the no ECLS group. ECLS stabilization improved end-organ function pre-VAD implant with significant improvements in hepatic and renal dysfunction. This series demonstrates that the use of ECLS bridge to VAD stabilizes end-organ dysfunction and reduces VAD implant perioperative mortality from that traditionally reported in these "crash and burn" patients. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Spanish validation of the Premorbid Adjustment Scale (PAS-S).

Science.gov (United States)

Barajas, Ana; Ochoa, Susana; Baños, Iris; Dolz, Montse; Villalta-Gil, Victoria; Vilaplana, Miriam; Autonell, Jaume; Sánchez, Bernardo; Cervilla, Jorge A; Foix, Alexandrina; Obiols, Jordi E; Haro, Josep Maria; Usall, Judith

2013-02-01

The Premorbid Adjustment Scale (PAS) has been the most widely used scale to quantify premorbid status in schizophrenia, coming to be regarded as the gold standard of retrospective assessment instruments. To examine the psychometric properties of the Spanish version of the PAS (PAS-S). Retrospective study of 140 individuals experiencing a first episode of psychosis (n=77) and individuals who have schizophrenia (n=63), both adult and adolescent patients. Data were collected through a socio-demographic questionnaire and a battery of instruments which includes the following scales: PAS-S, PANSS, LSP, GAF and DAS-sv. The Cronbach's alpha was performed to assess the internal consistency of PAS-S. Pearson's correlations were performed to assess the convergent and discriminant validity. The Cronbach's alpha of the PAS-S scale was 0.85. The correlation between social PAS-S and total PAS-S was 0.85 (p<0.001); while for academic PAS-S and total PAS-S it was 0.53 (p<0.001). Significant correlations were observed between all the scores of each age period evaluated across the PAS-S scale, with a significance value less than 0.001. There was a relationship between negative symptoms and social PAS-S (0.20, p<0.05) and total PAS-S (0.22, p<0.05), but not with academic PAS-S. However, there was a correlation between academic PAS-S and general subscale of the PANSS (0.19, p<0.05). Social PAS-S was related to disability measures (DAS-sv); and academic PAS-S showed discriminant validity with most of the variables of social functioning. PAS-S did not show association with the total LSP scale (discriminant validity). The Spanish version of the Premorbid Adjustment Scale showed appropriate psychometric properties in patients experiencing a first episode of psychosis and who have a chronic evolution of the illness. Moreover, each domain of the PAS-S (social and academic premorbid functioning) showed a differential relationship to other characteristics such as psychotic symptoms, disability

Bridge maintenance to enhance corrosion resistance and performance of steel girder bridges

Science.gov (United States)

Moran Yanez, Luis M.

The integrity and efficiency of any national highway system relies on the condition of the various components. Bridges are fundamental elements of a highway system, representing an important investment and a strategic link that facilitates the transport of persons and goods. The cost to rehabilitate or replace a highway bridge represents an important expenditure to the owner, who needs to evaluate the correct time to assume that cost. Among the several factors that affect the condition of steel highway bridges, corrosion is identified as the main problem. In the USA corrosion is the primary cause of structurally deficient steel bridges. The benefit of regular high-pressure superstructure washing and spot painting were evaluated as effective maintenance activities to reduce the corrosion process. The effectiveness of steel girder washing was assessed by developing models of corrosion deterioration of composite steel girders and analyzing steel coupons at the laboratory under atmospheric corrosion for two alternatives: when high-pressure washing was performed and when washing was not considered. The effectiveness of spot painting was assessed by analyzing the corrosion on steel coupons, with small damages, unprotected and protected by spot painting. A parametric analysis of corroded steel girder bridges was considered. The emphasis was focused on the parametric analyses of corroded steel girder bridges under two alternatives: (a) when steel bridge girder washing is performed according to a particular frequency, and (b) when no bridge washing is performed to the girders. The reduction of structural capacity was observed for both alternatives along the structure service life, estimated at 100 years. An economic analysis, using the Life-Cycle Cost Analysis method, demonstrated that it is more cost-effective to perform steel girder washing as a scheduled maintenance activity in contrast to the no washing alternative.

Strength monitoring of bridge constructions and features of its application. Part 2. Continuous monitoring of bridge construction status

Directory of Open Access Journals (Sweden)

Ovchinnikov Igor Georgievich

2014-06-01

Full Text Available The article describes a system of continuous monitoring of bridge constructions — a system of observation over the operating conditions and behavior of the bridge structure, which is aimed at ensuring the preservation of its functional application properties within the specified limits, realized on the continuous, long-term basis with the use of instrumentation and ensures on-line presentation of information on the status of structure. To illustrate, one may consider the existing systems of continuous monitoring for a number of bridge constructions in the United States, Japan, Europe, South Korea, Greece and Russia. The article suggests to examine the systems of continuous monitoring of «Commodore John Barry» truss bridge, «Akashi-Kaikyo» suspension bridge, «Siggenthal» reinforced-concrete arch bridge, «Nimhe» suspension bridge, «Jindo»cable-stayed bridge, «Yandzhon» suspension bridge, «Banghwa» bridge, «Seohae» bridge and «Rio-Antirrio» bridge. In addition one may consider monitoring of the longitudinal launching of the bridge superstructures over the Volga River near the village Pristannoye in Saratov region. Finally, it was drawn the conclusion that monitoring of bridge constructions from the standpoint of their consumers is aimed at solving such important problems as preservation of bridge structures, increase in service life of bridge structures through timely detection of faults and their elimination, as well as preservation of bridge structure carrying capacity by controlling their behavior during the operation and improving the efficiency of expenditure of monetary resources for repair activities by correct determination of time and type of the necessary repair.

Field performance of timber bridges. 15, Pueblo County, Colorado, stress-laminated deck bridge

Science.gov (United States)

L. E. Hislop

The Pueblo County 204B bridge was constructed in March 1990 in Pueblo, Colorado, as a demonstration bridge under the USDA Forest Service Timber Bridge Initiative. The stress-laminated deck superstructure is approximately 10 m long, 9 m wide, and 406 mm deep, with a skew of 10 degrees. Performance monitoring was conducted for 3 years, beginning at...

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......, and as an example the reliability profile and a sensitivity analyses for a corroded reinforced concrete bridge is shown....

Design and construction of superstructure in prestressed concrete cable-stayed bridge. ; Aomori Bay Bridge. PC shachokyo jobuko no sekkei to seko. ; Aomori Bay Bridge

Energy Technology Data Exchange (ETDEWEB)

Ishibashi, T.; Fujimori, S.; Oba, M.; Tsuyoshi, T. (East Japan Railway Co., Tokyo (Japan))

1991-12-01

Aomori Bay Bridge is a 1,219m long elevated bridge, a part of No.2 Bay Highway of 1,993m in total length crossing over Aomori railway station which was planned in ordecr to integrate the port facilities of Aomori Harbor and expedite cargo traffic smoothly. Of this Bay Bridge, its main bridge portion crossing over Aomori railway station and the sea area was planned as a continuous prestressed concrete cable-stayed bridge of 498m in total length and consisting of three portions including the central portion in which the main span between the central bridge piers was 240m. It is scheduled to open in the summer of 1992. With regard to the design of this bridge, special care for the view of the bridge has been taken covering from the structure style to the accessories. For this bridge, a large scale underground continuous wall solid base with a box-shaped section consisting of 6 chambers was adopted for the base of a main tower. It has the cantilever suspension structure of the wide girder with the inverted Y-shaped pylons. For its stav cable, was adopted a large capacity stay cable with standard tensile strength of 1,942 fabricated on the site and for its covering tube, a FRP tube was adopted. In this article, the construction of the main girder and stay cables, and the construction control during their installation by projection are reported. 7 refs., 14 figs., 9 tabs.

Impact Coefficient Analysis of Long-Span Railway Cable-Stayed Bridge Based on Coupled Vehicle-Bridge Vibration

Directory of Open Access Journals (Sweden)

Yongle Li

2015-01-01

Full Text Available Compared with medium and small span bridges, very limited attention has been paid on the research of the impact coefficient of long-span railway bridges. To estimate the impact effects of long-span railway bridges subjected to moving vehicles, a real long-span railway cable-stayed bridge is regarded as the research object in this study, and a coupled model of vehicle-bridge system is established. The track irregularities are taken as the system excitation and the dynamic responses of the vehicle-bridge system are calculated. The impact effects on main girder, stayed cable, bearings, and bridge tower are discussed at various vehicle speeds. The results show that different components of the long-span railway cable-stayed bridge have different impact coefficients. Even for each part, the impact coefficient is also different at different local positions. It reveals that the impact coefficients in the actual situation may have significant differences with the related code clauses in the present design codes.

Field performance of timber bridges. 8, Lynches Woods Park stress-laminated deck bridge

Science.gov (United States)

J. P. Wacker; M. A. Ritter; D. Conger

The Lynches Woods Park bridge was constructed during the summer of 1990 in Newberry, South Carolina. It is a single-span, single-lane, stress-laminated deck superstructure that measures approximately 30 ft long, 16 ft wide, and 14 in. deep. The bridge is unique in that is one of the first known stress-laminated deck bridges to be constructed of Southern Pine lumber...

Salt-bridge energetics in halophilic proteins.

Science.gov (United States)

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

2014-01-01

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

Bridge the Gap

DEFF Research Database (Denmark)

Marselis, Randi

2017-01-01

This article focuses on photo projects organised for teenage refugees by the Society for Humanistic Photography (Berlin, Germany). These projects, named Bridge the Gap I (2015), and Bridge the Gap II (2016), were carried out in Berlin and brought together teenagers with refugee and German...

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

Influence of welding passes on grain orientation – The example of a multi-pass V-weld

International Nuclear Information System (INIS)

Ye, Jing; Moysan, Joseph; Song, Sung-Jin; Kim, Hak-Joon; Chassignole, Bertrand; Gueudré, Cécile; Dupond, Olivier

2012-01-01

The accurate modelling of grain orientations in a weld is important, when accurate ultrasonic test predictions of a welded assembly are needed. To achieve this objective, Electricité de France (EDF) and the Laboratoire de Caractérisation Non Destructive (LCND) have developed a dedicated code, which makes use of information recorded in the welding procedure. Among the welding parameters recorded, although the order in which the welding passes are made is of primary importance in the welding process, this information is not always well known or accurately described. In the present paper we analyse in greater detail the influence of the order of welding passes, using data obtained from the Centre for Advanced Non Destructive Evaluation (CANDE), derived from a dissimilar metal weld (DMW) with buttering. Comparisons are made using grain orientation measurements on a macrograph. - Highlights: ► Influence of welding process on grain structure is studied using the MINA model. ► For the first time the importance of a slight slope of the layers is evaluated. ► Two orders of passes are compared for the modelling approach. ► A major effect is observed due to a change in the order of passes.

Field performance of timber bridges. 12, Christian Hollow stress-laminated box-beam bridge

Science.gov (United States)

J. P. Wacker; S. C. Catherman; R. G. Winnett

In January 1992, the Christian Hollow bridge was constructed in Steuben County, New York. The bridge is a single-span, stress-laminated box-beam superstructure that is 9.1 m long, 9.8 m wide, and 502 mm deep (30 ft long, 32 ft wide, and 19-3/4 in. deep). The performance of the bridge was continuously monitored for 28 months, beginning shortly after installation....

Deep Borehole Instrumentation Along San Francisco Bay Bridges: 1996 - 2003 and Strong Ground Motion Systhesis Along the San Francisco/Oakland Bay Bridge

Energy Technology Data Exchange (ETDEWEB)

Hutchings, L; Foxall, W; Kasameyer, P; larsen, S; Hayek, C; Tyler-Turpin, C; Aquilino, J; Long, L

2005-04-22

frequency calculations (Hz > 0.7) based on empirical Green's functions with finite difference calculations for frequencies less than 0.7 Hz. We found that in the near-source region, far-field shear-wave generation and near-field tectonic ground displacements can result in very large long period ground displacements and velocity pulses. Far-field arrivals have the strongest energy in periods of about 2 to 5 s, and near-field arrivals have the strongest energy in periods of about 5 to 10 s. Much of these near-source ground motions would not be observed by conventional strong motion recording systems, which typically are high-pass band limited at 2-5 s periods, and therefore have not been included as standard practice structural input ground motions. For some fault rupture scenarios, the large tectonic displacement pulse would initially drive the bridge with motions parallel to tectonic fault displacement, and before the bridge would start to rebound, the far-field S-wave would arrive and drive the bridge in the opposite direction. This type of multiple long-period modal response can occur in other long period structures such as base-isolated systems and tall buildings.

Road Bridges and Culverts, Bridge dataset only includes bridges maintained by Johnson County Public Works in the unincorporated areas, Published in Not Provided, Johnson County Government.

Data.gov (United States)

NSGIC Local Govt | GIS Inventory — Road Bridges and Culverts dataset current as of unknown. Bridge dataset only includes bridges maintained by Johnson County Public Works in the unincorporated areas.

Passing the baton

CERN Multimedia

2011-01-01

It was not only in South Korea that batons were being passed last week. While the cream of the world’s athletes were competing in the World Athletics Championships, the cream of the world’s accelerator scientists were on their way to San Sebastian in Spain for the International Particle Accelerator Conference.  One of them was carrying a rather special baton for a handover of a different kind.   When Fermilab’s Vladimir Shiltsev handed the high-energy frontier baton to CERN’s Mike Lamont on Tuesday, it marked the end of an era: a time to look back on the phenomenal contribution the Tevatron has made to particle physics over its 25-year operational lifetime, and the great contribution Fermilab has made over that period to global collaboration in particle physics. There’s always a lot of emotion involved in passing the baton. In athletics, it’s the triumph of wining or the heartbreak of losing. But for this special baton, the...

Fish pass assessment by remote control: a novel framework for quantifying the hydraulics at fish pass entrances

Science.gov (United States)

Kriechbaumer, Thomas; Blackburn, Kim; Gill, Andrew; Breckon, Toby; Everard, Nick; Wright, Ros; Rivas Casado, Monica

2014-05-01

Fragmentation of aquatic habitats can lead to the extinction of migratory fish species with severe negative consequences at the ecosystem level and thus opposes the target of good ecological status of rivers defined in the EU Water Framework Directive (WFD). In the UK, the implementation of the EU WFD requires investments in fish pass facilities of estimated 532 million GBP (i.e. 639 million Euros) until 2027 to ensure fish passage at around 3,000 barriers considered critical. Hundreds of passes have been installed in the past. However, monitoring studies of fish passes around the world indicate that on average less than half of the fish attempting to pass such facilities are actually successful. There is a need for frameworks that allow the rapid identification of facilities that are biologically effective and those that require enhancement. Although there are many environmental characteristics that can affect fish passage success, past research suggests that variations in hydrodynamic conditions, reflected in water velocities, velocity gradients and turbulences, are the major cues that fish use to seek migration pathways in rivers. This paper presents the first steps taken in the development of a framework for the rapid field-based quantification of the hydraulic conditions downstream of fish passes and the assessment of the attractivity of fish passes for salmonids and coarse fish in UK rivers. For this purpose, a small-sized remote control platform carrying an acoustic Doppler current profiler (ADCP), a GPS unit, a stereo camera and an inertial measurement unit has been developed. The large amount of data on water velocities and depths measured by the ADCP within relatively short time is used to quantify the spatial and temporal distribution of water velocities. By matching these hydraulic features with known preferences of migratory fish, it is attempted to identify likely migration routes and aggregation areas at barriers as well as hydraulic features that

Laboratory Testing of Precast Bridge Beck Panel Transverse Connections for Use in Accelerated Bridge Construction

OpenAIRE

Porter, Scott D.

2009-01-01

Precast concrete bridge deck panels have been used for decades to accelerate bridge construction. Cracking of the transverse connection between panels is a common problem that can damage deck overlays and cause connection leaking leading to corrosion of lower bridge elements. To better understand the behavior of bridge deck transverse female-to-female connections, shear and moment lab testing were performed at Utah State University for the Utah Department of Transportation. Two existing UDOT ...

Human Errors and Bridge Management Systems

DEFF Research Database (Denmark)

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

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...... for reinforced concrete bridges....

A bridge with a view, a view with a bridge : Identifying design considerations for bridges to strengthen regional identity

NARCIS (Netherlands)

Smits, J.E.P.; van der Hoeven, F.D.

2015-01-01

This paper discusses design considerations for creating high quality infrastructural artefacts with an emphasis on bridges. The authors pursue a design study and analysis approach to highlight the specifics of infrastructure design for regional identity, based on their own work on a bridge

Precast concrete elements for accelerated bridge construction : laboratory testing, field testing, evaluation of a precast concrete bridge, Madison County bridge.

Science.gov (United States)

2009-01-01

The importance of rapid construction technologies has been recognized by the Federal Highway Administration (FHWA) and the Iowa : DOT Office of Bridges and Structures. Recognizing this a two-lane single-span precast box girder bridge was constructed ...

BUILDING A BETTER GLUTEAL BRIDGE: ELECTROMYOGRAPHIC ANALYSIS OF HIP MUSCLE ACTIVITY DURING MODIFIED SINGLE-LEG BRIDGES.

Science.gov (United States)

Lehecka, B J; Edwards, Michael; Haverkamp, Ryan; Martin, Lani; Porter, Kambry; Thach, Kailey; Sack, Richard J; Hakansson, Nils A

2017-08-01

Gluteal strength plays a role in injury prevention, normal gait patterns, eliminating pain, and enhancing athletic performance. Research shows high gluteal muscle activity during a single-leg bridge compared to other gluteal strengthening exercises; however, prior studies have primarily measured muscle activity with the active lower extremity starting in 90 ° of knee flexion with an extended contralateral knee. This standard position has caused reports of hamstring cramping, which may impede optimal gluteal strengthening. The purpose of this study was to determine which modified position for the single-leg bridge is best for preferentially activating the gluteus maximus and medius. Cross-Sectional. Twenty-eight healthy males and females aged 18-30 years were tested in five different, randomized single-leg bridge positions. Electromyography (EMG) electrodes were placed on subjects' gluteus maximus, gluteus medius, rectus femoris, and biceps femoris of their bridge leg (i.e., dominant or kicking leg), as well as the rectus femoris of their contralateral leg. Subjects performed a maximal voluntary isometric contraction (MVIC) for each tested muscle prior to performing five different bridge positions in randomized order. All bridge EMG data were normalized to the corresponding muscle MVIC data. A modified bridge position with the knee of the bridge leg flexed to 135 ° versus the traditional 90 ° of knee flexion demonstrated preferential activation of the gluteus maximus and gluteus medius compared to the traditional single-leg bridge. Hamstring activation significantly decreased (p bridge by flexing the active knee to 135 ° instead of 90 ° minimizes hamstring activity while maintaining high levels of gluteal activation, effectively building a bridge better suited for preferential gluteal activation. 3.

The violin bridge as filter.

Science.gov (United States)

Bissinger, George

2006-07-01

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

Analysis of Biomechanical Structure and Passing Techniques in Basketball

OpenAIRE

Ricardo E. Izzo; Luca Russo

2011-01-01

The basketball is a complex sport, which these days has become increasingly linked to its’ psychophysical aspects rather than to the technical ones. Therefore, it is important to make a through study of the passing techniques from the point of view of the type of the pass and its’ biomechanics. From the point of view of the type of the used passes, the most used is the two-handed chest pass with a frequency of 39.9%. This is followed, in terms of frequency, by one-handed passes – the baseball...

Role of multiprotein bridging factor 1 in archaea: bridging the domains?

NARCIS (Netherlands)

Koning, de B.; Blombach, F.; Wu Hao,; Brouns, S.J.J.; Oost, van der J.

2009-01-01

MBF1 (multiprotein bridging factor 1) is a highly conserved protein in archaea and eukaryotes. It was originally identified as a mediator of the eukaryotic transcription regulator BmFTZ-F1 (Bombyx mori regulator of fushi tarazu). MBF1 was demonstrated to enhance transcription by forming a bridge

23 CFR 650.809 - Movable span bridges.

Science.gov (United States)

2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Movable span bridges. 650.809 Section 650.809 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.809 Movable span bridges. A fixed bridge...

Sustainable Bridge Infrastructure Procurement

DEFF Research Database (Denmark)

Safi, Mohammed; Du, Guangli; Simonsson, Peter

2016-01-01

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

Message Passing Framework for Globally Interconnected Clusters

International Nuclear Information System (INIS)

Hafeez, M; Riaz, N; Asghar, S; Malik, U A; Rehman, A

2011-01-01

In prevailing technology trends it is apparent that the network requirements and technologies will advance in future. Therefore the need of High Performance Computing (HPC) based implementation for interconnecting clusters is comprehensible for scalability of clusters. Grid computing provides global infrastructure of interconnecting clusters consisting of dispersed computing resources over Internet. On the other hand the leading model for HPC programming is Message Passing Interface (MPI). As compared to Grid computing, MPI is better suited for solving most of the complex computational problems. MPI itself is restricted to a single cluster. It does not support message passing over the internet to use the computing resources of different clusters in an optimal way. We propose a model that provides message passing capabilities between parallel applications over the internet. The proposed model is based on Architecture for Java Universal Message Passing (A-JUMP) framework and Enterprise Service Bus (ESB) named as High Performance Computing Bus. The HPC Bus is built using ActiveMQ. HPC Bus is responsible for communication and message passing in an asynchronous manner. Asynchronous mode of communication offers an assurance for message delivery as well as a fault tolerance mechanism for message passing. The idea presented in this paper effectively utilizes wide-area intercluster networks. It also provides scheduling, dynamic resource discovery and allocation, and sub-clustering of resources for different jobs. Performance analysis and comparison study of the proposed framework with P2P-MPI are also presented in this paper.

Geometrical influences on multi-pass laser forming

International Nuclear Information System (INIS)

Edwardson, S P; Abed, E; Bartkowiak, K; Dearden, G; Watkins, K G

2006-01-01

Laser forming (LF) offers the industrial promise of controlled shaping of metallic and non-metallic components for prototyping, the correction of design shape or distortion and precision adjustment applications. The potential process advantages include precise incremental adjustment, flexibility of application and no mechanical 'spring-back' effect. To date there has been a considerable amount of work carried out on two-dimensional LF, using multi-pass straight line scan strategies to produce a reasonably controlled bend angle in a number of materials, including aerospace alloys. A key area, however, where there is a limited understanding, is the variation in bend angle per pass during multi-pass LF along a single irradiation track; in particular, the decrease in bend angle per pass after many irradiations for a given set of process parameters. Understanding this is essential if the process is to be fully controlled in a manufacturing environment. The research presented in this paper highlights the current theories as to why this occurs and proposes a further reason based on the geometrical effects of the component deformation, which in turn influences the process parameters per pass. This theory is confirmed through empirical analysis of the 2D LF process

Nonlinearity in oscillating bridges

Directory of Open Access Journals (Sweden)

Filippo Gazzola

2013-09-01

Full Text Available We first recall several historical oscillating bridges that, in some cases, led to collapses. Some of them are quite recent and show that, nowadays, oscillations in suspension bridges are not yet well understood. Next, we survey some attempts to model bridges with differential equations. Although these equations arise from quite different scientific communities, they display some common features. One of them, which we believe to be incorrect, is the acceptance of the linear Hooke law in elasticity. This law should be used only in presence of small deviations from equilibrium, a situation which does not occur in widely oscillating bridges. Then we discuss a couple of recent models whose solutions exhibit self-excited oscillations, the phenomenon visible in real bridges. This suggests a different point of view in modeling equations and gives a strong hint how to modify the existing models in order to obtain a reliable theory. The purpose of this paper is precisely to highlight the necessity of revisiting the classical models, to introduce reliable models, and to indicate the steps we believe necessary to reach this target.

Coupling vibration research on Vehicle-bridge system

Science.gov (United States)

Zhou, Jiguo; Wang, Guihua

2018-01-01

The vehicle-bridge coupling system forms when vehicle running on a bridge. It will generate a relatively large influence on the driving comfort and driving safe when the vibration of the vehicle is bigger. A three-dimensional vehicle-bridge system with biaxial seven degrees of freedom has been establish in this paper based on finite numerical simulation. Adopting the finite element transient numerical simulation to realize the numerical simulation of vehicle-bridge system coupling vibration. Then, analyze the dynamic response of vehicle and bridge while different numbers of vehicles running on the bridge. Got the variation rule of vertical vibration of car body and bridge, and that of the contact force between the wheel and bridge deck. The research results have a reference value for the analysis about the vehicle running on a large-span cabled bridge.

Nondestructive testing for bridge diagnosis

International Nuclear Information System (INIS)

Oshima, Toshiyuki; Mikami, Shuichi; Yamazaki, Tomoyuki

1997-01-01

There are many motivations for bridge diagnosis using Nondestructive testing (NDT) to monitor its integrity. The measured frequency and damping on real bridge are compared in one figure as a function of span length and general aspects are explained. These date were measured in every construction of bridges and applied to design new bridges. Ultrasonic testing is also well used for concrete and steel members mainly to detect internal damages or delaminations. Detail analysis on reflected waves gives us more accurate information about the defect. Experimental results are shown as examples in this paper.

Salt bridges: geometrically specific, designable interactions.

Science.gov (United States)

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

2011-03-01

Salt bridges occur frequently in proteins, providing conformational specificity and contributing to molecular recognition and catalysis. We present a comprehensive analysis of these interactions in protein structures by surveying a large database of protein structures. Salt bridges between Asp or Glu and His, Arg, or Lys display extremely well-defined geometric preferences. Several previously observed preferences are confirmed, and others that were previously unrecognized are discovered. Salt bridges are explored for their preferences for different separations in sequence and in space, geometric preferences within proteins and at protein-protein interfaces, co-operativity in networked salt bridges, inclusion within metal-binding sites, preference for acidic electrons, apparent conformational side chain entropy reduction on formation, and degree of burial. Salt bridges occur far more frequently between residues at close than distant sequence separations, but, at close distances, there remain strong preferences for salt bridges at specific separations. Specific types of complex salt bridges, involving three or more members, are also discovered. As we observe a strong relationship between the propensity to form a salt bridge and the placement of salt-bridging residues in protein sequences, we discuss the role that salt bridges might play in kinetically influencing protein folding and thermodynamically stabilizing the native conformation. We also develop a quantitative method to select appropriate crystal structure resolution and B-factor cutoffs. Detailed knowledge of these geometric and sequence dependences should aid de novo design and prediction algorithms. Copyright © 2010 Wiley-Liss, Inc.

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...... management systems are presently being implemented by bridge authorities in several countries. The prototype of an expert system for concrete bridge management is presented in this paper, with its functionality relying on two modules. The inspection module relies on a periodic acquisition of field...... information complemented by a knowledge-based interactive system, BRIDGE-1. To optimize management strategies at the headquarters, the BRIDGE-2 module was implemented, including three submodules: inspection strategy, maintenance and repair....

Model predictive control for a dual active bridge inverter with a floating bridge

OpenAIRE

Chowdhury, Shajjad; Wheeler, Patrick W.; Gerada, C.; Patel, Chintan

2016-01-01

This paper presents a Model Predictive Control technique applied to a dual active bridge inverter where one of the bridges is floating. The proposed floating bridge topology eliminates the need for isolation transformer in a dual inverter system and therefore reduces the size, weight and losses in the system. To achieve multilevel output voltage waveforms the floating inverter DC link capacitor is charged to the half of the main DC link voltage. A finite-set Model Predictive Control technique...

Gain claming in single-pass and double-pass L-band erbium-doped fiber amplifiers

International Nuclear Information System (INIS)

Harun, S.W.; Ahmad, H.

2004-01-01

Gain clamping is demonstrated in single-pass and double-pass long wavelength band erbium-doped fiber amplifiers. A C/L-band wavelength division multiplexing coupler is used in single-pass system to generate a laser at 1566 nm. The gain for the amplifier is clamped at 15.5 dB with gain variation of less than 0.2 dB from input signal power of -40 to -14 dBm with almost negligible noise figure penalty. However, the flatness of gain spectrum is slightly degraded due to the un-optimisation of erbium-doped fiber length. The advantage of this configuration is that the oscillating light does not appear at the output of the amplifier. A highly efficient gain-clamped long wavelength band erbium-doped fiber amplifiers with improved noise figure characteristic is demonstrated by simply adding a broadband conventional band fiber Bragg grating in double pass system. The combination of the fiber Bragg grating and optical circulator has created laser in the cavity for gain clamping. By adjusting the power combination of pumps 1 and 2, the clamped gain level can be controlled. The amplifier gain is clamped at 28.1 dB from -40 to -25 dBm with gain variation of less than 0.5 dB by setting the pumps 1 and 2 at 59.5 and 50.6 mW, respectively. The gain is also flat from 1574 nm to 1604 nm with gain variation of less than 3 dB. The corresponding noise figure varies from 5.6 to 7.6 dB, which is 0.8 to 2.6 dB reduced compared to those of unclamped amplifier (Authors)

Bridge over troubled water?

DEFF Research Database (Denmark)

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

2008-01-01

The problem of integrating non-Western immigrants into Western welfare states is the focus of this paper. To address this issue, we suggest a social capital approach in which we apply the conceptual pair of bridging social capital (BR), which connects an individual to the broader social structure...... relationship between the levels of bridging and bonding capital, suggesting that bonding social capital in the immigrant group does not seem to impede the establishment of the bridging social capital needed for integration....

Bridge and steel structures. History and vision on bridge erection; Kyoryo kokozobutsu. Kasetsu gijutsu no shorai

Energy Technology Data Exchange (ETDEWEB)

Mukai, S.; Hayashi, T. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

1998-08-20

This paper describes the progress of bridge erection technology. It introduces the results of cable erection, rotated/extruded erection, and cantilever erection. The cable erection is a multi point suspension erection using cables. For the rotated/extruded erection, the monolithic construction is conducted on a working yard set in a right angle to the construction position, and the horizontal beams of the bridge piers (corbel girders) are constructed by the rotated method using a slewing base incorporated around the bridge piers at one side. For the construction of stiffening girders of Innoshima-ohashi Bridge of Honshu-Shikoku Joint Bridge in 1978, trussed face bar blocks were extruded from the main tower in order using a travel crane. For the suspension bridges and cable stayed bridges, main towers were erected using various types of cranes. The erection of Tamashima-ohashi Bridge with a weight of 500 ton using an offshore floating crane is introduced as a large block method. Analysis methods and measurement techniques at the site are used in order to analyze the shape in each step under the erection and to ensure the accurate final complete shape. Reduction of the construction cost, improvement of erection technology, and technology development for large-scale projects are subjects in the future. 22 refs., 8 figs., 1 tab.

Dragon bridge - the world largest dragon-shaped (ARCH steel bridge as element of smart city

Directory of Open Access Journals (Sweden)

Chinh Luong Minh

2016-01-01

Full Text Available Dragon Bridge - The world’s largest dragon-shaped steel bridge, with an installation cost of $85 million USD, features 6 lanes for two separate directions, 666 meters of undulating steel in the shape of a dragon in the Ly Dynasty, the symbol of prosperity in Vietnamese culture. This unique and beautifully lit bridge, which also breathes fire and sprays water. It’s the purposeful integration of the lighting hardware articulates the dragon’s form, and the fire-breathing dragon head. This project transcends the notion of monumental bridge with dynamic colour-changing lighting, creating an iconic sculpture in the skyline that is both reverent and whimsical. The signature feature of the bridge was the massive undulating support structure resembling a dragon flying over the river. The dragon is prominent in Vietnamese culture as a symbol of power and nobility. Dragon Bridge stands out as a model of innovation. It has received worldwide attention in the design community and from the global media for its unique arch support system. Dragon Bridge serves as an example of how aesthetic quality of a design can serve cultural, economic and functional purposes. The article presents design solutions of the object and the evaluation of the technical condition before putting the facility into service.

Experimental investigation of different fill materials in arch bridges with particular focus on Pearl-Chain Bridges

DEFF Research Database (Denmark)

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

2016-01-01

Pearl-Chain Bridge technology is a recently developed prefabricated arch solution for road and railway bridges allowing faster, more environmentally friendly, and cheaper bridge construction. This study compared the strength and durability properties of three different types of fill material...

Bridge element deterioration rates.

Science.gov (United States)

2008-10-01

This report describes the development of bridge element deterioration rates using the NYSDOT : bridge inspection database using Markov chains and Weibull-based approaches. It is observed : that Weibull-based approach is more reliable for developing b...

Bridge-Vehicle Impact Assessment

Science.gov (United States)

2011-08-01

Bridges in New York State have been experiencing close to 200 bridge hits a year. These : accidents are attributed to numerous factors including: improperly stored equipment on trucks; : violation of vehicle posting signs; illegal commercial vehicles...

Bridge vehicle impact assessment.

Science.gov (United States)

2011-12-01

Bridges in New York State have been experiencing close to 200 bridge hits a year. These : accidents are attributed to numerous factors including: improperly stored equipment on trucks; : violation of vehicle posting signs; illegal commercial vehicles...

Wireless Smart Sensor Network System Using SmartBridge Sensor Nodes for Structural Health Monitoring of Existing Concrete Bridges

Science.gov (United States)

Gaviña, J. R.; Uy, F. A.; Carreon, J. D.

2017-06-01

There are over 8000 bridges in the Philippines today according to the Department of Public Works and Highways (DPWH). Currently, visual inspection is the most common practice in monitoring the structural integrity of bridges. However, visual inspections have proven to be insufficient in determining the actual health or condition of a bridge. Structural Health Monitoring (SHM) aims to give, in real-time, a diagnosis of the actual condition of the bridge. In this study, SmartBridge Sensor Nodes were installed on an existing concrete bridge with American Association of State Highway and Transportation Officials (AASHTO) Type IV Girders to gather vibration of the elements of the bridge. Also, standards on the effective installation of SmartBridge Sensor Nodes, such as location and orientation was determined. Acceleration readings from the sensor were then uploaded to a server, wherein they are monitored against certain thresholds, from which, the health of the bridge will be derived. Final output will be a portal or webpage wherein the information, health, and acceleration readings of the bridge will be available for viewing. With levels of access set for different types of users, the main users will have access to download data and reports. Data transmission and webpage access are available online, making the SHM system wireless.

Retail Bank Interest Rate Pass-Through; Is Chile Atypical?

OpenAIRE

Alessandro Rebucci; Marco A Espinosa-Vega

2003-01-01

This paper investigates empirically the pass-through of money market interest rates to retail banking interest rates in Chile, the United States, Canada, Australia, New Zealand, and five European countries. Overall, Chile's pass-through does not appear atypical. Based on a standard error-correction model, we find that, as in most countries considered, Chile's measured pass-through is incomplete. But Chile's pass-through is also faster than in many other countries considered and is comparable ...

North Texas Sediment Budget: Sabine Pass to San Luis Pass

Science.gov (United States)

2006-09-01

concrete units have been placed over sand-filled fabric tube . .......................................33 Figure 28. Sand-filled fabric tubes protecting...system UTM Zone 15, NAD 83 Longshore drift directions King (in preparation) Based on wave hindcast statistics and limited buoy data Rollover Pass...along with descriptions of the jetties and limited geographic coordinate data1 (Figure 18). The original velum or Mylar sheets from which the report

Horizontal bridges in polar dielectric liquids

Science.gov (United States)

Woisetschläger, Jakob; Wexler, Adam D.; Holler, Gert; Eisenhut, Mathias; Gatterer, Karl; Fuchs, Elmar C.

2012-01-01

When a high-voltage direct-current is applied to two beakers filled with polar liquid dielectrica like water or methanol, a horizontal bridge forms between the two beakers. By repeating a version of Pellat's experiment, it is shown that a horizontal bridge is stable by the action of electrohydrodynamic pressure. Thus, the static and dynamic properties of the phenomenon called a `floating water bridge' can be explained by the gradient of Maxwell pressure, replenishing the liquid within the bridge against any drainage mechanism. It is also shown that a number of liquids can form stable and long horizontal bridges. The stability of such a connection, and the asymmetry in mass flow through such bridges caused by the formation of ion clouds in the vicinity of the electrodes, is also discussed by two further experiments.

LTBP bridge performance primer.

Science.gov (United States)

2013-12-01

"The performance of bridges is critical to the overall performance of the highway transportation system in the United States. However, many critical aspects of bridge performance are not well understood. The reasons for this include the extreme diver...

33 CFR 115.70 - Advance approval of bridges.

Science.gov (United States)

2010-07-01

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

The Maastricht-Duke bridge: An era of mentoring in clinical research - A model for mentoring in clinical research - A tribute to Dr. Galen Wagner.

Science.gov (United States)

Meijs, Loek; Zusterzeel, Robbert; Wellens, Hein Jj; Gorgels, Anton Pm

With the passing of Dr. Galen Wagner, an exceptional collaboration between Maastricht University Medical Center, The Netherlands, and Duke Clinical Research Institute, USA, has come to an end. This article focuses on the background of what Galen coined the Maastricht-Duke bridge (MD-bridge), its merits, limitations and development throughout the years, and his special role. Between 2004 and 2015, 23 Maastricht University medical students and post-graduate students were enrolled in the 4-month research elective, mentored by Galen and the Maastricht co-mentor. They were asked to complete a survey about their MD-bridge experience. Sixteen out of the 23 students responded. None but 1 participant had prior research experience. Following their MD bridge-program most participants published 1 or more manuscripts and/or presented their research in an international setting. They felt they had full responsibility as a leader of their project with all participants developing meaningful skills useful in their current job. Fourteen out of 16 would recommend the MD-bridge experience to others. Participants considered the program of great value for their personal growth and independence, giving a feeling of achievement. In addition, for some participants it led to careers in foreign countries including medical practice and research, or obtaining PhDs. With Galen's impressive career of mentoring students, including the 23 MD-bridge participants, he has left behind an amazing concept of self-development in research and personal life. The successes of the MD-bridge prove that it is possible for students to be young investigators during or just after medical school with the potential to contribute to developing meaningful skills and noteworthy careers. Collaborations between international universities, such as the MD-bridge, are feasible and should be embraced by other institutions. Published by Elsevier Inc.

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.

Bridge Scour Technology Transfer

Science.gov (United States)

2018-01-24

Scour and flooding are the leading causes of bridge failures in the United States and therefore should be monitored. New applications of tools and technologies are being developed, tested, and implemented to reduce bridge scour risk. The National Coo...

Revised Rules for Concrete Bridges

DEFF Research Database (Denmark)

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

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

The stories of two bridges in Ghana

DEFF Research Database (Denmark)

Andreasen, Jørgen

2004-01-01

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

Analysis of Biomechanical Structure and Passing Techniques in Basketball

Directory of Open Access Journals (Sweden)

Ricardo E. Izzo

2011-06-01

Full Text Available The basketball is a complex sport, which these days has become increasingly linked to its’ psychophysical aspects rather than to the technical ones. Therefore, it is important to make a through study of the passing techniques from the point of view of the type of the pass and its’ biomechanics. From the point of view of the type of the used passes, the most used is the two-handed chest pass with a frequency of 39.9%. This is followed, in terms of frequency, by one-handed passes – the baseball, with 20.9 % – and by the two-handed over the head pass, with 18.2 %, and finally, one- or two-handed indirect passes (bounces, with 11.2 % and 9.8 %. Considering the most used pass in basketball, from the biomechanical point of view, the muscles involved in the correct movement consider all the muscles of the upper extremity, adding also the shoulder muscles as well as the body fixators (abdominals, hip flexors, knee extensors, and dorsal flexors of the foot. The technical and conditional analysis considers the throwing speed, the throw height and the air resistance. In conclusion, the aim of this study is to give some guidelines to improve the mechanical execution of the movements in training, without neglecting the importance of the harmony of the movements themselves.

Bridging the Gap

DEFF Research Database (Denmark)

Dahlberg, Rasmus

2016-01-01

The fixed link between Denmark and Sweden connects two busy cities and a large international airport with many of its travelers and employees. 18,000 vehicles and 160 passenger trains transport each day more than 70,000 people across the combined road and rail Øresund Bridge and through the Øresu...... in its final report to the Danish and Swedish transport authorities while drawing upon experiences from two recent comparable cases of infrastructure disruptions: The Champlain Bridge (2009) and the Forth Road Bridge (2015).......The fixed link between Denmark and Sweden connects two busy cities and a large international airport with many of its travelers and employees. 18,000 vehicles and 160 passenger trains transport each day more than 70,000 people across the combined road and rail Øresund Bridge and through the Øresund...... Tunnel, approximately 25,000 of them critical to the regional work market. Even though the risk analysis states that the likelihood of a long-term closure (100C days) is very low Danish and Swedish transport authorities have demanded that the infrastructure operator conducts a survey of the preparedness...

Mouse myocardial first-pass perfusion MR imaging

NARCIS (Netherlands)

Coolen, Bram F.; Moonen, Rik P. M.; Paulis, Leonie E. M.; Geelen, Tessa; Nicolay, Klaas; Strijkers, Gustav J.

2010-01-01

A first-pass myocardial perfusion sequence for mouse cardiac MRI is presented. A segmented ECG-triggered acquisition combined with parallel imaging acceleration was used to capture the first pass of a Gd-DTPA bolus through the mouse heart with a temporal resolution of 300-400 msec. The method was

49 CFR 236.766 - Locking, movable bridge.

Science.gov (United States)

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Locking, movable bridge. 236.766 Section 236.766... Locking, movable bridge. The rail locks, bridge locks, bolt locks, circuit controllers, and electric locks used in providing interlocking protection at a movable bridge. ...

Dynamic assessment of bridge deck performance considering realistic bridge-traffic interaction : research brief

Science.gov (United States)

2017-09-01

This study is to develop simulation methodology to conduct the dynamic assessment of bridge deck performance subjected to traffic. Concrete bridge decks are exposed to daily traffic loads and may experience some surface cracking caused by excessive s...

Development of a precast bridge deck overhang system for the rock creek bridge.

Science.gov (United States)

2008-12-01

Precast, prestressed panels are commonly used at interior beams for bridges in Texas. The use of these : panels provides ease of construction, sufficient capacity, and good economy for the construction of : bridges in Texas. Current practice for the ...

Measurement of the Dynamic Displacements of Railway Bridges Using Video Technology

Directory of Open Access Journals (Sweden)

Ribeiro Diogo

2015-01-01

Full Text Available This article describes the development of a non-contact dynamic displacement measurement system for railway bridges based on video technology. The system, consisting of a high speed video camera, an optical lens, lighting lamps and a precision target, can perform measurements with high precision for distances from the camera to the target up to 25 m, with acquisition frame rates ranging from 64 fps to 500 fps, and be articulated with other measurement systems, which promotes its integration in structural health monitoring systems. The system’s performance was evaluated based on two tests, one in the laboratory and other on the field. The laboratory test evaluated the performance of the system in measuring the displacement of a steel beam, subjected to a point load applied dynamically, for distances from the camera to the target between 3 m and 15 m. The field test allowed evaluating the system’s performance in the dynamic measurement of the displacement of a point on the deck of a railway bridge, induced by passing trains at speeds between 160 km/h and 180 km/h, for distances from the camera to the target up to 25 m. The results of both tests show a very good agreement between the displacement measurement obtained with the video system and with a LVDT.

Behavioral study of selected microorganisms in an aqueous electrohydrodynamic liquid bridge.

Science.gov (United States)

Paulitsch-Fuchs, Astrid H; Zsohár, Andrea; Wexler, Adam D; Zauner, Andrea; Kittinger, Clemens; de Valença, Joeri; Fuchs, Elmar C

2017-07-01

An aqueous electrohydrodynamic (EHD) floating liquid bridge is a unique environment for studying the influence of protonic currents (mA cm -2 ) in strong DC electric fields (kV cm -1 ) on the behavior of microorganisms. It forms in between two beakers filled with water when high-voltage is applied to these beakers. We recently discovered that exposure to this bridge has a stimulating effect on Escherichia coli. . In this work we show that the survival is due to a natural Faraday cage effect of the cell wall of these microorganisms using a simple 2D model. We further confirm this hypothesis by measuring and simulating the behavior of Bacillus subtilis subtilis , Neochloris oleoabundans, Saccharomyces cerevisiae and THP-1 monocytes. Their behavior matches the predictions of the model: cells without a natural Faraday cage like algae and monocytes are mostly killed and weakened, whereas yeast and Bacillus subtilis subtilis survive. The effect of the natural Faraday cage is twofold: First, it diverts the current from passing through the cell (and thereby killing it); secondly, because it is protonic it maintains the osmotic pressure in the cell wall, thereby mitigating cytolysis which would normally occur due to the low osmotic pressure of the surrounding medium. The method presented provides the basis for selective disinfection of solutions containing different microorganisms.

Behavioral study of selected microorganisms in an aqueous electrohydrodynamic liquid bridge

Directory of Open Access Journals (Sweden)

Astrid H. Paulitsch-Fuchs

2017-07-01

Full Text Available An aqueous electrohydrodynamic (EHD floating liquid bridge is a unique environment for studying the influence of protonic currents (mA cm−2 in strong DC electric fields (kV cm−1 on the behavior of microorganisms. It forms in between two beakers filled with water when high-voltage is applied to these beakers. We recently discovered that exposure to this bridge has a stimulating effect on Escherichia coli.. In this work we show that the survival is due to a natural Faraday cage effect of the cell wall of these microorganisms using a simple 2D model. We further confirm this hypothesis by measuring and simulating the behavior of Bacillus subtilis subtilis, Neochloris oleoabundans, Saccharomyces cerevisiae and THP-1 monocytes. Their behavior matches the predictions of the model: cells without a natural Faraday cage like algae and monocytes are mostly killed and weakened, whereas yeast and Bacillus subtilis subtilis survive. The effect of the natural Faraday cage is twofold: First, it diverts the current from passing through the cell (and thereby killing it; secondly, because it is protonic it maintains the osmotic pressure in the cell wall, thereby mitigating cytolysis which would normally occur due to the low osmotic pressure of the surrounding medium. The method presented provides the basis for selective disinfection of solutions containing different microorganisms.

Field performance of timber bridges. 13, Mohawk Canal stress-laminated bridge

Science.gov (United States)

P. D. Hilbrich Lee; X. Lauderdale

The Mohawk Canal bridge was constructed in August 1994, just outside Roll, Arizona. It is a simple-span, double-lane, stress-laminated deck superstructure, approximately 6.4 m (21 ft) long and 10.4 m (34 ft) wide and constructed with Combination 16F-V3 Douglas Fir glued-laminated timber beam laminations. The performance of the bridge was monitored continuously for 2...

Development of inspection robots for bridge cables.

Science.gov (United States)

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

2013-01-01

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

Horizontal bridges in polar dielectric liquids

Energy Technology Data Exchange (ETDEWEB)

Woisetschlaeger, Jakob [Graz University of Technology, Experimental Turbomachinery Research and Optical Measurement Group, Institute for Thermal Turbomachinery and Machine Dynamics, Graz (Austria); Wexler, Adam D.; Fuchs, Elmar C. [Wetsus, Center of Excellence for Sustainable Water Technology, Leeuwarden (Netherlands); Holler, Gert [Graz University of Technology, Institute of Electrical Measurement and Measurement Signal Processing, Graz (Austria); Eisenhut, Mathias [Graz University of Technology, Institute of Analytical Chemistry and Food Chemistry, Graz (Austria); Gatterer, Karl [Graz University of Technology, Institute of Physical and Theoretical Chemistry, Graz (Austria)

2012-01-15

When a high-voltage direct-current is applied to two beakers filled with polar liquid dielectrica like water or methanol, a horizontal bridge forms between the two beakers. By repeating a version of Pellat's experiment, it is shown that a horizontal bridge is stable by the action of electrohydrodynamic pressure. Thus, the static and dynamic properties of the phenomenon called a 'floating water bridge' can be explained by the gradient of Maxwell pressure, replenishing the liquid within the bridge against any drainage mechanism. It is also shown that a number of liquids can form stable and long horizontal bridges. The stability of such a connection, and the asymmetry in mass flow through such bridges caused by the formation of ion clouds in the vicinity of the electrodes, is also discussed by two further experiments. (orig.)

Lean Construction Applications for Bridge Inspection

Science.gov (United States)

2017-10-01

Lean philosophy was used to analyze the efficiency of bridge inspection. Emphasis was put on identifying activities that add value to the final output, an owner approved bridge inspection report. 26 bridge inspections were shadowed. Time spent on bri...

Spread prestressed concrete slab beam bridges.

Science.gov (United States)

2015-04-01

TxDOT uses prestressed slab beam bridges for short-span bridges ranging from approximately 3050 ft in : length. These bridges have precast, pretensioned slab beams placed immediately adjacent to one another : with a cast-in-place slab made composi...

Mouse myocardial first-pass perfusion MR imaging

NARCIS (Netherlands)

Coolen, B.F.; Moonen, R.P.M.; Paulis, L.E.M.; Geelen, T.; Nicolay, K.; Strijkers, G.J.

2010-01-01

A first-pass myocardial perfusion sequence for mouse cardiac MRI is presented. A segmented ECG-triggered acquisition combined with parallel imaging acceleration was used to capture the first pass of a Gd-DTPA bolus through the mouse heart with a temporal resolution of 300–400 msec. The method was

12 CFR 560.32 - Pass-through investments.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Pass-through investments. 560.32 Section 560.32 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF THE TREASURY LENDING AND INVESTMENT Lending and Investment Powers for Federal Savings Associations § 560.32 Pass-through investments. (a) A...

Hydrodynamic forces on inundated bridge decks

Science.gov (United States)

2009-05-01

The hydrodynamic forces experienced by an inundated bridge deck have great importance in the design of bridges. Specifically, the drag force, lift force, and the moment acting on the bridge deck under various levels of inundation and a range of flow ...

Pass-Through to Import Prices: Evidence from Developing Countries

OpenAIRE

Miguel Fuentes

2007-01-01

In this paper I study the pass-through of nominal exchange rate changes to the price of imported goods in four developing countries. The results indicate that 75% of changes in the exchange rate are passed-through to the domestic currency price of imported goods within one quarter. Complete pass-through is attained within one year. There is no evidence that exchange rate pass-through to the price of imported goods has declined over time even in those countries that have managed to reduce infl...

Development of Inspection Robots for Bridge Cables

Directory of Open Access Journals (Sweden)

Hae-Bum Yun

2013-01-01

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

Design and construction of Chiburiko Bridge (stress ribbon bridge). Chiburiko bashi (tsurishoban kyo) no sekkei to seko

Energy Technology Data Exchange (ETDEWEB)

Kamisakoda, K; Tokuyama, S; Sano, K; Onuma, K [Kashima Corp., Tokyo (Japan)

1992-07-30

Chiburiko Bridge lies across Chiburiko which is a lake for agricultural water, and is used by people, carts and cars for administration. It is a stressed-ribbon bridge with the road surface made with concrete covered bands of cables stretched between abutments, and is the first highway bridge in Japan. A report is made on the plan and construction of the bridge. Integration of the precast slab with the cast-in-place concrete as well as mutual integration of the precast slabs are validated by the use of a reproduced model of a part of the bridge. Floor slabs are suspended by cables, and can be constructed with no form nor support by integrating cast-in-place concrete with the precast slabs on mutually joined precast slabs. It has been said that the stressed-ribbon bridge has a structure suitable for long span bridges because it has a simple structure. Studies, however, seems to be necessary on the impact caused by running of vehicles and on the wind resisting stability. 3 refs., 17 figs., 2 tabs.

The South Carolina bridge-scour envelope curves

Science.gov (United States)

Benedict, Stephen T.; Feaster, Toby D.; Caldwell, Andral W.

2016-09-30

The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, conducted a series of three field investigations to evaluate historical, riverine bridge scour in the Piedmont and Coastal Plain regions of South Carolina. These investigations included data collected at 231 riverine bridges, which lead to the development of bridge-scour envelope curves for clear-water and live-bed components of scour. The application and limitations of the South Carolina bridge-scour envelope curves were documented in four reports, each report addressing selected components of bridge scour. The current investigation (2016) synthesizes the findings of these previous reports into a guidance manual providing an integrated procedure for applying the envelope curves. Additionally, the investigation provides limited verification for selected bridge-scour envelope curves by comparing them to field data collected outside of South Carolina from previously published sources. Although the bridge-scour envelope curves have limitations, they are useful supplementary tools for assessing the potential for scour at riverine bridges in South Carolina.

Assessment of structural condition of Libeň Bridge

Directory of Open Access Journals (Sweden)

Kněž Petr

2017-01-01

Full Text Available The paper presents diagnostic and load tests of the Inundation bridge which is part of a group of bridges called The Libeň bridge group in Prague. The Libeň bridge group consists of two arched and several framed bridges spanning the Vltava river. One of the vaulted bridges consists of 5 arches and the other vaulted bridge (called Inundation bridge consists of only one arch. Arched bridges are extraordinary structures with both technical and historical value. Since the inundation bridge has the largest arch of whole group, it was selected for testing purposes. The bridge is assembled with three-hinged arch made of concrete. The hinges are made of reinforced concrete and lead contact slabs. Detailed measurements of geometry and material properties were made on the bridge. Based on these measurements a computer model was created to verify the behavior of the structure. Both static and dynamic calculations were performed. Measurements of dynamic characteristics were made during normal operation and with hydraulic vibration exciter. This article will focus on comparing the results of dynamic calculation of the modeled structure and properties measured on real structure excited by hydraulic vibration exciter.

Students design composite bridges

NARCIS (Netherlands)

Stark, J.W.B.; Galjaard, J.C.; Brekelmans, J.W.P.M.

1999-01-01

The paper gives an overview of recent research on steel-concrete composite bridge design by students of Delft University of Technology doing their master's thesis. Primary objective of this research was to find possibilities for application of steel-concrete composite bridges in the Netherlands,

33 CFR 118.140 - Painting bridge piers.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Painting bridge piers. 118.140 Section 118.140 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.140 Painting bridge piers. The District Commander may require...

Superconductivity in small metal bridges

International Nuclear Information System (INIS)

Hannah, E.C.

1975-01-01

Josephson effects in weaklinks are discussed for low and high frequency regimes using simple perturbation techniques. It is proven that no measurement of the supercurrent dependence upon frequency above the Riedel peak frequency can be made using rf sources whose frequencies are below the Riedel peak. Thus the bulk of work done in the field on the high frequency structure of the Josephson current is shown to be invalid. Metal bridges shorter than a newly defined temperature independent length for superconductors, l/sub PHONON/, are proven to be identical in their Josephson current behavior to tunneling junctions. The BCS gap equation is generalized to include voltage gradient effects on pairs within the bridge. The oscillation frequency for long bridges (l/sub BRIDGE/ greater than l/sub PHONON/) is shown to be limited to less than 10'' Hz. An experimental test of the new voltage dependent gap is made as well as tests of the pair reforming time of bridges

Diversifying the Midwifery Workforce: Inclusivity, Culturally Sensitive Bridging, and Innovation.

Science.gov (United States)

Tyson, Holliday; Wilson-Mitchell, Karline

2016-11-01

Midwifery educators and regulators in Canada have begun to address diversity, equity, and inclusion in admission processes and program curricula. Populations served by midwives value internationally educated midwives from their countries of origin. The International Midwifery Pre-Registration Program at Ryerson University in Toronto, Ontario, provides assessment, midwifery workplace orientation, and accelerated education for internationally educated midwives on behalf of the regulatory College of Midwives of Ontario. Between 2003 and 2015, midwives from 41 countries participated in the bridging program, and 214 (80%) successfully completed the program and qualified for licensure. Of these 214 graduates, 100% passed the Canadian Midwifery Registration Examination and 193 (90%) were employed full time as midwives within 4 months of graduation. The program curriculum enables the integration of these midwives into health care workplaces utilizing innovative approaches to assessment and competency enhancement. Critical to the bridging process are simulation-based practices to develop effective psychomotor learning, virtual and real primary care community placements, and coaching in empathetic, client-centered communication. Cultural sensitivity is embedded into the multiple assessment and learning modalities, and addresses relevant barriers faced by immigrant midwives in the workplace. Findings from the 13 years of the program may be applicable to increase diversity in other North American midwifery settings. This article describes the process, content, outcomes, and findings of the program. Midwifery educators and regulators may consider the utility of these approaches for their settings. © 2016 by the American College of Nurse-Midwives.

Bridge scour monitoring technologies : development of evaluation and selection protocols for application on river bridges in Minnesota.

Science.gov (United States)

2010-03-01

Bridge failure or loss of structural integrity can result from scour of riverbed sediment near bridge abutments or : piers during high-flow events in rivers. In the past 20 years, several methods of monitoring bridge scour have been : developed spann...

36 CFR 13.918 - Sable Pass Wildlife Viewing Area.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Sable Pass Wildlife Viewing... Preserve General Provisions § 13.918 Sable Pass Wildlife Viewing Area. (a) Entry into the Sable Pass Wildlife Viewing Area is prohibited from May 1 to September 30 unless authorized by the Superintendent. (b...

Time-varying exchange rate pass-through: experiences of some industrial countries

OpenAIRE

Toshitaka Sekine

2006-01-01

This paper estimates exchange rate pass-through of six major industrial countries using a time-varying parameter with stochastic volatility model. Exchange rate pass-through is divided into impacts of exchange rate fluctuations to import prices (first-stage pass-through) and those of import price movements to consumer prices (second-stage pass-through). The paper finds that both stages of pass-through have declined over time for all the sample countries. The decline in second-stage pass-throu...

Multiple Bistability in Quinonoid-Bridged Diiron(II) Complexes: Influence of Bridge Symmetry on Bistable Properties.

Science.gov (United States)

van der Meer, Margarethe; Rechkemmer, Yvonne; Breitgoff, Frauke D; Marx, Raphael; Neugebauer, Petr; Frank, Uta; van Slageren, Joris; Sarkar, Biprajit

2016-11-21

Quinonoid bridges are well-suited for generating dinuclear assemblies that might display various bistable properties. In this contribution we present two diiron(II) complexes where the iron(II) centers are either bridged by the doubly deprotonated form of a symmetrically substituted quinonoid bridge, 2,5-bis[4-(isopropyl)anilino]-1,4-benzoquinone (H 2 L2') with a [O,N,O,N] donor set, or with the doubly deprotonated form of an unsymmetrically substituted quinonoid bridge, 2-[4-(isopropyl)anilino]-5-hydroxy-1,4-benzoquinone (H 2 L5') with a [O,O,O,N] donor set. Both complexes display temperature-induced spin crossover (SCO). The nature of the SCO is strongly dependent on the bridging ligand, with only the complex with the [O,O,O,N] donor set displaying a prominent hysteresis loop of about 55 K. Importantly, only the latter complex also shows a pronounced light-induced spin state change. Furthermore, both complexes can be oxidized to the mixed-valent iron(II)-iron(III) form, and the nature of the bridge determines the Robin and Day classification of these forms. Both complexes have been probed by a battery of electrochemical, spectroscopic, and magnetic methods, and this combined approach is used to shed light on the electronic structures of the complexes and on bistability. The results presented here thus show the potential of using the relatively new class of unsymmetrically substituted bridging quinonoid ligands for generating intriguing bistable properties and for performing site-specific magnetic switching.

33 CFR 118.90 - Bridges crossing channel obliquely.

Science.gov (United States)

2010-07-01

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

33 CFR 118.100 - Retroreflective panels on bridge piers.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Retroreflective panels on bridge... SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.100 Retroreflective panels on bridge piers. The... 12 inches square. (c) To mark bridge piers or channel sides on bridges not required to have bridge...

Concrete-Filled Steel Tube Arch Bridges in China

Directory of Open Access Journals (Sweden)

Jielian Zheng

2018-02-01

Full Text Available In the past 20 years, great progress has been achieved in China in the construction of concrete-filled steel tube (CFST arch bridges and concrete arch bridges with a CFST skeleton. The span of these bridges has been increasing rapidly, which is rare in the history of bridge development. The large-scale construction of expressways and high-speed railways demands the development of long-span arch bridges, and advances in design and construction techniques have made it possible to construct such bridges. In the present study, the current status, development, and major innovative technologies of CFST arch bridges and concrete arch bridges with a CFST skeleton in China are elaborated. This paper covers the key construction technologies of CFST arch bridges, such as the design, manufacture, and installation of steel tube arch trusses, the preparation and pouring of in-tube concrete, and the construction of the world’s longest CFST arch bridge—the First Hejiang Yangtze River Bridge. The main construction technologies of reinforced concrete arch bridges are also presented, which include cable-stayed fastening-hanging cantilever assembly, adjusting the load by means of stay cables, surrounding the concrete for arch rib pouring, and so forth. In addition, the construction of two CFST skeleton concrete arch bridges—the Guangxi Yongning Yong River Bridge and the Yunnan–Guangxi Railway Nanpan River Bridge—is discussed. CFST arch bridges in China have already gained a world-leading position; with the continuous innovation of key technologies, China will become the new leader in promoting the development of arch bridges. Keywords: Concrete-filled steel tube (CFST arch bridge, Steel-reinforced concrete arch bridge, Cable-stayed fastening-hanging cantilever assembly, Vacuum-assisted pouring in-tube concrete, Adjusting load by stay cables

A First-Order One-Pass CPS Transformation

DEFF Research Database (Denmark)

Danvy, Olivier; Nielsen, Lasse Reichstein

2002-01-01

We present a new transformation of call-by-value lambdaterms into continuation-passing style (CPS). This transformation operates in one pass and is both compositional and first-order. Because it operates in one pass, it directly yields compact CPS programs that are comparable to what one would...... write by hand. Because it is compositional, it allows proofs by structural induction. Because it is first-order, reasoning about it does not require the use of a logical relation. This new CPS transformation connects two separate lines of research. It has already been used to state a new and simpler...... correctness proof of a direct-style transformation, and to develop a new and simpler CPS transformation of control-flow information....

Reliability Modeling of Double Beam Bridge Crane

Science.gov (United States)

Han, Zhu; Tong, Yifei; Luan, Jiahui; Xiangdong, Li

2018-05-01

This paper briefly described the structure of double beam bridge crane and the basic parameters of double beam bridge crane are defined. According to the structure and system division of double beam bridge crane, the reliability architecture of double beam bridge crane system is proposed, and the reliability mathematical model is constructed.

LIGHT BRIDGE IN A DEVELOPING ACTIVE REGION. I. OBSERVATION OF LIGHT BRIDGE AND ITS DYNAMIC ACTIVITY PHENOMENA

International Nuclear Information System (INIS)

Toriumi, Shin; Katsukawa, Yukio; 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 a 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, the Interface Region Imaging Spectrograph, and the Solar Dynamics Observatory, 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 a large-scale convective upflow and is surrounded by strong, vertical fields of adjacent pores. In the chromosphere above the bridge, a transient brightening occurs repeatedly and intermittently, followed by a recurrent dark surge ejection into higher altitudes. Our analysis indicates that the brightening is the plasma heating due to magnetic reconnection at lower altitudes, while the dark surge is the cool, dense plasma ejected from the reconnection region. From the observational results, we conclude that the dynamic activity observed in a light bridge structure such as chromospheric brightenings and dark surge ejections are driven by magnetoconvective evolution within the light bridge and its interaction with the surrounding magnetic fields

LIGHT BRIDGE IN A DEVELOPING ACTIVE REGION. I. OBSERVATION OF LIGHT BRIDGE AND ITS DYNAMIC ACTIVITY PHENOMENA

Energy Technology Data Exchange (ETDEWEB)

Toriumi, Shin; Katsukawa, Yukio [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Cheung, Mark C. M., E-mail: shin.toriumi@nao.ac.jp [Lockheed Martin Solar and Astrophysics Laboratory, 3251 Hanover Street, Building/252, Palo Alto, CA 94304 (United States)

2015-10-01

Light bridges, the bright structures that divide the umbra of sunspots and pores into smaller pieces, are known to produce a 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, the Interface Region Imaging Spectrograph, and the Solar Dynamics Observatory, 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 a large-scale convective upflow and is surrounded by strong, vertical fields of adjacent pores. In the chromosphere above the bridge, a transient brightening occurs repeatedly and intermittently, followed by a recurrent dark surge ejection into higher altitudes. Our analysis indicates that the brightening is the plasma heating due to magnetic reconnection at lower altitudes, while the dark surge is the cool, dense plasma ejected from the reconnection region. From the observational results, we conclude that the dynamic activity observed in a light bridge structure such as chromospheric brightenings and dark surge ejections are driven by magnetoconvective evolution within the light bridge and its interaction with the surrounding magnetic fields.

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...... decisive for choosing the form of trusses, arches and cable-stayed bridges are outlined, and several examples show bridges designed without giving priority to the structural aspects....

Strategies For The Replacement Of Historic Bridge Guardrails

OpenAIRE

Clauss, Adam J.

2014-01-01

Bridges that are designated historic present a special challenge to bridge engineers whenever rehabilitation work or improvements are made to the bridges. Federal and state laws protect historically significant bridges, and railings on these bridges can be subject to protection because of the role they play in aesthetics. Unfortunately, original railings on historic bridges do not typically meet current crash-test requirements and typically do not meet current standards for railing height and...

When, where and how the bridge breaks: anaphase bridge breakage plays a crucial role in gene amplification and HSR generation

International Nuclear Information System (INIS)

Shimizu, Noriaki; Shingaki, Kenta; Kaneko-Sasaguri, Yukiko; Hashizume, Toshihiko; Kanda, Teru

2005-01-01

Amplified genes are frequently localized on extrachromosomal double minutes (DMs) or in chromosomal homogenously staining regions (HSRs). We previously showed that a plasmid bearing a mammalian replication initiation region could efficiently generate DMs and HSRs after transfection into human tumor cell lines. The Breakage-Fusion-Bridge (BFB) cycle model, a classical model that explains how HSRs form, could also be used to explain how the transfected plasmids generate HSRs. The BFB cycle model involves anaphase bridge formation due to the presence of dicentric chromosomes, followed by the breakage of the bridge. In this study, we used our plasmid-based model system to analyze how anaphase bridges break during mitosis. Dual-color fluorescence in situ hybridization analyses revealed that anaphase bridges were most frequently severed in their middle irrespective of their lengths, which suggests that a structurally fragile site exists in the middle of the anaphase bridge. Breakage of the chromosomal bridges occurred prior to nuclear membrane reformation and the completion of cytokinesis, which indicates that mechanical tension rather than cytokinesis is primarily responsible for severing anaphase bridges. Time-lapse observation of living cells revealed that the bridges rapidly shrink after being severed. If HSR length was extended too far, the bridge could no longer be resolved and became tangled depending on the tension. The unbroken bridge appeared to inhibit the completion of cytokinesis. These observations strongly suggest that anaphase bridges are highly elastic and that the length of the spindle axis determines the maximal HSR length

[Morphology research of the rat sciatic nerve bridged by collage-heparin sulfate scaffold].

Science.gov (United States)

Wang, Shu-sen; Hu, Yun-yu; Luo, Zhuo-jing; Chen, Liang-wei; Liu, Hui-ling; Meng, Guo-lin; Lü, Rong; Xu, Xin-zhi

2005-04-15

To observe the treating effect of collage-heparin sulfate after the 10 mm rat sciatic nerve defect was bridged by it. A new kind of nervous tissue engineering scaffold was produced by freeze-drying technique from collagen-heparin sulfate. Thirty-two SD rats were randomly divided into A, B, C and D groups. Sciatic nerve defect in group A was bridged by collagen-heparin sulfate. In group B, sciatic nerve was bridged by auto-nerve transplantation. Group C was the blank control group. Animals in group D were normal. And 10 mm sciatic nerve defect was bridged in the experiment. Thirty-six weeks after the operation, the experimental animals were detected by HRP labeled retrograde trace, HE staining, toluidine staining, silvering staining, S100, GAP-43 and NF immunohistological staining, MBP immunofluorescence staining and transmission electron microscope to observe the nerve regeneration inducing effect of this new scaffold. Nine months after operation, the collage-heparin sulfate scaffold was replaced by newly regenerated nerve. The number of HRP labeled spinal cord anterior horn cells and the area of sensation nerve fiber at the posterior horn were similar with that was repaired by auto-nerve. GAP-43, NF and S100 labeled regenerated nerve fiber had passed the total scaffold and entered the distal terminal. The regenerated nerve fibers were paralleled, lineage arranged, coincide with the prearranged regenerating "channel" in the collagen-heparin sulfate scaffold. MBP immunofluorescence staining also proved that the newly regenerated nerve fiber could be ensheathed. In the experimental group, the area of myelinated nerve fiber and the thickness of the myelin sheath had no obvious difference with that of the group repaired by auto-nerve, except that the density of the regenerated myelinated sheath fiber was lower than that of the control group. Nervous tissue engineering scaffold produced by collagen-heparin sulfate can guide the regeneration of nerve fibers. The nerve

33 CFR 118.70 - Lights on swing bridges.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on swing bridges. 118.70 Section 118.70 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.70 Lights on swing bridges. (a) Swing span lights on through bridges. Each...

33 CFR 118.65 - Lights on fixed bridges.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on fixed bridges. 118.65 Section 118.65 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.65 Lights on fixed bridges. (a) Each fixed bridge span over a navigable...

23 CFR 650.409 - Evaluation of bridge inventory.

Science.gov (United States)

2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Evaluation of bridge inventory. 650.409 Section 650.409... Evaluation of bridge inventory. (a) Sufficiency rating of bridges. Upon receipt and evaluation of the bridge inventory, a sufficiency rating will be assigned to each bridge by the Secretary in accordance with the...

Effects of Electrolyte on Floating Water Bridge

OpenAIRE

Hideo Nishiumi; Fumitaka Honda

2009-01-01

Fuchs found phenomena that when high voltage is applied to deionized water filled in two contacted beakers, a floating water bridge forms spontaneously. In this paper, we examined flow direction of water bridge and what effects the addition of electrolytes such as NaCl, NaOH, and N H 4 C l to the floating water bridge would give. We found that ionization degree reduced the length of water bridge though insoluble electrolyte A l 2 O 3 had no effect on the length of water bridge.

A data management infrastructure for bridge monitoring

Science.gov (United States)

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

2015-04-01

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

Railway bridge monitoring during construction and sliding

Science.gov (United States)

Inaudi, Daniele; Casanova, Nicoletta; Kronenberg, Pascal; Vurpillot, Samuel

1997-05-01

The Moesa railway bridge is a composite steel concrete bridge on three spans of 30 m each. The 50 cm thick concrete deck is supported on the lower flanges of two continuous, 2.7 m high I-beams. The bridge has been constructed alongside an old metallic bridge. After demolishing this one, the new bridge has been slid for 5 m by 4 hydraulic jacks and positioned on the refurbished piles of the old bridge. About 30 fiber optic, low-coherence sensors were imbedded in the concrete deck to monitor its deformations during concrete setting and shrinkage, as well as during the bridge sliding phase. In the days following concrete pour it was possible to follow its thermal expansion due to the exothermic setting reaction and the following thermal and during shrinkage. The deformations induced by the additional load produced by the successive concreting phases were also observed. During the bridge push, which extended over six hours, the embedded and surface mounted sensors allowed the monitoring of the curvature variations in the horizontal plane due to the slightly uneven progression of the jacks. Excessive curvature and the resulting cracking of concrete could be ruled out by these measurements. It was also possible to observe the bridge elongation under the heating action of the sun.

On the effect of nuclear bridge modes on donor-acceptor electronic coupling in donor-bridge-acceptor molecules

International Nuclear Information System (INIS)

Davis, Daly; Toroker, Maytal Caspary; Speiser, Shammai; Peskin, Uri

2009-01-01

We report a theoretical study of intra-molecular electronic coupling in a symmetric DBA (donor-bridge-acceptor) complex, in which a donor electronic site is coupled to an acceptor site by way of intervening orbitals of a molecular bridge unit. In the off-resonant (deep tunneling) regime of electronic transport, the lowest unoccupied molecular orbitals (MO's) of the DBA system are split into distinguishable donor/acceptor and bridge orbitals. The effect of geometrical changes at the bridge on the donor/acceptor electronic energy manifold is studied for local stretching and bending modes. It is demonstrated that the energy splitting in the manifold of donor/acceptor unoccupied MOs changes in response to such changes, as assumed in simple McConnell-type models. Limitations of the simple models are revealed where the electronic charging of the bridge orbitals correlates with increasing donor/acceptor orbital energy splitting only for stretching but not for bending bridge modes.

IceBridge Mission Flight Reports

Data.gov (United States)

National Aeronautics and Space Administration — The IceBridge Mission Flight Reports data set contains flight reports from NASA Operation IceBridge Greenland, Arctic, Antarctic, and Alaska missions. Flight reports...

Integrated Cu-based TM-pass polarizer using CMOS technology platform

KAUST Repository

Ng, Tien Khee; Khan, Mohammed Zahed Mustafa; Ooi, Boon S.

2010-01-01

A transverse-magnetic-pass (TM-pass) copper (Cu) polarizer is proposed and analyzed using the previously published two-dimensional Method-of-Lines beam-propagation model. The proposed polarizer exhibits a simulated high-pass filter characteristics

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...

Virtual Bridge Design Challenge

Science.gov (United States)

Mitts, Charles R.

2013-01-01

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

The floating water bridge

International Nuclear Information System (INIS)

Fuchs, Elmar C; Woisetschlaeger, Jakob; Gatterer, Karl; Maier, Eugen; Pecnik, Rene; Holler, Gert; Eisenkoelbl, Helmut

2007-01-01

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

Double-pass quantum volume hologram

International Nuclear Information System (INIS)

Vasilyev, Denis V.; Sokolov, Ivan V.

2011-01-01

We propose a scheme for parallel, spatially multimode quantum memory for light. The scheme is based on the propagation in different directions of a quantum signal wave and strong classical reference wave, like in a classical volume hologram and the previously proposed quantum volume hologram [D. V. Vasilyev et al., Phys. Rev. A 81, 020302(R) (2010)]. The medium for the hologram consists of a spatially extended ensemble of cold spin-polarized atoms. In the absence of the collective spin rotation during the interaction, two passes of light for both storage and retrieval are required, and therefore the present scheme can be called a double-pass quantum volume hologram. The scheme is less sensitive to diffraction and therefore is capable of achieving a higher density of storage of spatial modes as compared to the previously proposed thin quantum hologram [D. V. Vasilyev et al., Phys. Rev. A 77, 020302(R) (2008)], which also requires two passes of light for both storage and retrieval. However, the present scheme allows one to achieve a good memory performance with a lower optical depth of the atomic sample as compared to the quantum volume hologram. A quantum hologram capable of storing entangled images can become an important ingredient in quantum information processing and quantum imaging.

MODERN ASPECTS OF BRIDGES MONITORING

Directory of Open Access Journals (Sweden)

M. I. Kazakevych

2007-12-01

Full Text Available The major concepts of the elaboration and realization of the bridge construction monitoring systemic approach are presented in this paper. The main peculiarity of the bridge monitoring modern aspect is pointed out here, namely, the transition from the demands of providing the reliability to the demands of providing the whole complex of the structure consumer qualities. The criteria of diagnostics of the bridge exploitation reliability as the fundamental aim of monitoring are formulated here.

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

Science.gov (United States)

2010-10-07

... INFORMATION CONTACT: Ms. Ann Shemaka, Office of Bridge Technology, HIBT-30, (202) 366-1575, or Mr. Thomas Everett, Office of Bridge Technology, HIBT-30, (202) 366-4675, Federal Highway Administration, 1200 New... is categorized by the following material types, which are identified in the NBI: steel, concrete, pre...

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

Science.gov (United States)

2012-08-31

... INFORMATION CONTACT: Ms. Ann Shemaka, Office of Bridge Technology, (202) 366-1575, or via email at [email protected] or Mr. Thomas Everett, Office of Bridge Technology, (202) 366-4675, or via email at thomas... the NBI: steel, concrete, pre-stressed concrete, and other. The category ``other'' includes wood...

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

Science.gov (United States)

2011-09-06

... INFORMATION CONTACT: Ms. Ann Shemaka, Office of Bridge Technology, HIBT-30, (202) 366-1575, or Mr. Thomas Everett, Office of Bridge Technology, HIBT-30, (202) 366-4675, Federal Highway Administration, 1200 New... is categorized by the following material types, which are identified in the NBI: steel, concrete, pre...

Prosthetic rehabilitation using adhesive bridge and fixed-fixed bridge on the maxilla and telescopic crown overdenture on mandible

Directory of Open Access Journals (Sweden)

Indah Sulistiawaty

2016-12-01

Full Text Available Prosthetic rehabilitation is the rehabilitation process of masticatory and esthetics function for patients missing teeth and alveolar bone by means of manufacture and installation of dentures. The prosthetic rehabilitation commonly used include denture adhesive bridge, fixed-fixed bridge, as well as telescopic overdenture. Adhesive bridge is bridge denture consisting of single pontic and two retainer wings attached to the abutment using cement or resin. Fixed-fixed bridge is a bridge denture with rigid connectors on both ends of the pontics, whereas the telescopic crown Overdenture is a removable denture that uses linked precision on the original tooth in the form of primary coping on abutment and secondary coping on the denture. To expose the procedures of prosthetic rehabilitation using adhesive bridge and fixed-fixed bridge on the maxilla and telescopic crown Overdenture on mandible. Male patients aged 32 years came with complaints of difficulty to chew food because he had lost some teeth behind. In the maxilla, teeth are lost in the region of 15 and 16 performed by making the fixed-fixed bridge with abutment teeth 14 and 17. Loss of teeth in the region of 26, performed the manufacture of adhesive bridge with a box preparation on the occlusal 25 and 27. In the mandible, tooth loss in the region of 36,37,46, and 47 performed manufacture of telescopic crown Overdenture with primer coping on the teeth 35.38, 45, and 48 and the secondary coping on a metal frame. Prosthetic rehabilitation especially in the case of loss of back teeth is very important because with the denture patients can chew properly and maintain the stomatognathic system.

Remediation: Higher Education's Bridge to Nowhere

Science.gov (United States)

Complete College America, 2012

2012-01-01

The intentions were noble. It was hoped that remediation programs would be an academic bridge from poor high school preparation to college readiness. Sadly, remediation has become instead higher education's "Bridge to Nowhere." This broken remedial bridge is travelled by some 1.7 million beginning students each year, most of whom will…

Notes on basis band-pass circuits; Notes sur les circuits de base passe-bande

Energy Technology Data Exchange (ETDEWEB)

Ailloud, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1959-07-01

Resistor load amplifier stages, basic band-pass RC networks, conventional single-tuned circuits, have the same transfer function. Common properties and differences because diverse magnitude of parameters with proposed problems are exposed. Next the case of several cascaded stages (or networks) is examined when there is no reaction ones to another. (author) [French] Les etages amplificateurs a resistances, les circuits passe-bande RC elementaires, le circuit resonnant classique possedent la meme fonction de transfert. On fait ressortir les proprietes communes et les differences de comportement dues aux ordres de grandeur qu'il est possible de donner aux parametres en fonction des problemes a resoudre. On examine ensuite le cas de plusieurs etages (ou de plusieurs circuits) en cascade lorsqu'ils ne reagissent pas les uns sur les autres. (auteur)

Effects of Electrolyte on Floating Water Bridge

Directory of Open Access Journals (Sweden)

Hideo Nishiumi

2009-01-01

spontaneously. In this paper, we examined flow direction of water bridge and what effects the addition of electrolytes such as NaCl, NaOH, and NH4Cl to the floating water bridge would give. We found that ionization degree reduced the length of water bridge though insoluble electrolyte Al2O3 had no effect on the length of water bridge.

Modeling drivers' passing duration and distance in a virtual environment

Directory of Open Access Journals (Sweden)

Haneen Farah

2013-07-01

The main contribution of this paper is in the empirical models developed for passing duration and distance which highlights the factors that affect drivers' passing behavior and can be used to enhance the passing models in simulation programs.

LIGHT BRIDGE IN A DEVELOPING ACTIVE REGION. II. NUMERICAL SIMULATION OF FLUX EMERGENCE AND LIGHT BRIDGE FORMATION

International Nuclear Information System (INIS)

Toriumi, Shin; Katsukawa, Yukio; Cheung, Mark C. M.

2015-01-01

Light bridges, the bright structure dividing umbrae in sunspot regions, show various activity events. In Paper I, we reported on an analysis of multi-wavelength observations of a light bridge in a developing active region (AR) and concluded that the activity events are caused by magnetic reconnection driven by magnetconvective evolution. The aim of this second paper is to investigate the detailed magnetic and velocity structures and the formation mechanism of light bridges. For this purpose, we analyze numerical simulation data from a radiative magnetohydrodynamics model of an emerging AR. We find that a weakly magnetized plasma upflow in the near-surface layers of the convection zone is entrained between the emerging magnetic bundles that appear as pores at the solar surface. This convective upflow continuously transports horizontal fields to the surface layer and creates a light bridge structure. Due to the magnetic shear between the horizontal fields of the bridge and the vertical fields of the ambient pores, an elongated cusp-shaped current layer is formed above the bridge, which may be favorable for magnetic reconnection. The striking correspondence between the observational results of Paper I and the numerical results of this paper provides a consistent physical picture of light bridges. The dynamic activity phenomena occur as a natural result of the bridge formation and its convective nature, which has much in common with those of umbral dots and penumbral filaments

Optimum Maintenance Strategies for Highway Bridges

DEFF Research Database (Denmark)

Frangopol, Dan M.; Thoft-Christensen, Palle; Das, Parag C.

As bridges become older and maintenance costs become higher, transportation agencies are facing challenges related to implementation of optimal bridge management programs based on life cycle cost considerations. A reliability-based approach is necessary to find optimal solutions based on minimum...... expected life-cycle costs or maximum life-cycle benefits. This is because many maintenance activities can be associated with significant costs, but their effects on bridge safety can be minor. In this paper, the program of an investigation on optimum maintenance strategies for different bridge types...... is described. The end result of this investigation will be a general reliability-based framework to be used by the UK Highways Agency in order to plan optimal strategies for the maintenance of its bridge network so as to optimize whole-life costs....

Investigation of Aerodynamic Interference between Twin Deck Bridges

Energy Technology Data Exchange (ETDEWEB)

Sitek, M. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC); Bojanowski, C. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC); Lottes, S. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC)

2016-05-01

Construction of a twin bridge can be a cost effective and minimally disruptive way to increase capacity when an existing bridge is not near the end of its service life. With ever growing vehicular traffic, when demand approaches the capacity of many existing roads and bridges. Remodeling a structure with an insufficient number of lanes can be a good solution in case of smaller and less busy bridges. Closing down or reducing traffic on crossings of greater importance for the construction period, however, can result in major delays and revenue loss for commerce and transportation as well as increasing the traffic load on alternate route bridges. Multiple-deck bridges may be the answer to this issue. A parallel deck can be built next to the existing one, without reducing the flow. Additionally, a new bridge can be designed as a twin or multi-deck structure. Several such structures have been built throughout the United States, among them: - The New NY Bridge Project - the Tappan Zee Hudson River Crossing, - SR-182 Columbia River Bridge, - The Thaddeus Kosciusko Bridge (I-87), - The Allegheny River Bridge, Pennsylvania, which carries I76, - Fred Hartman Bridge, TX, see Figure 1.2. With a growing number of double deck bridges, additional, more detailed, studies on the interaction of such bridge pairs in windy conditions appears appropriate. Aerodynamic interference effects should be examined to assure the aerodynamic stability of both bridges. There are many studies on aerodynamic response of single deck bridges, but the literature on double-deck structures is not extensive. The experimental results from wind tunnels are still limited in number, as a parametric study is required, they can be very time consuming. Literature review shows that some investigation of the effects of gap-width and angle of wind incidence has been done. Most of the CFD computational studies that have been done were limited to 2D simulations. Therefore, it is desirable to investigate twin decks

Review of Energy Harvesters Utilizing Bridge Vibrations

Directory of Open Access Journals (Sweden)

Farid Ullah Khan

2016-01-01

Full Text Available For health monitoring of bridges, wireless acceleration sensor nodes (WASNs are normally used. In bridge environment, several forms of energy are available for operating WASNs that include wind, solar, acoustic, and vibration energy. However, only bridge vibration has the tendency to be utilized for embedded WASNs application in bridge structures. This paper reports on the recent advancements in the area of vibration energy harvesters (VEHs utilizing bridge oscillations. The bridge vibration is narrowband (1 to 40 Hz with low acceleration levels (0.01 to 3.8 g. For utilization of bridge vibration, electromagnetic based vibration energy harvesters (EM-VEHs and piezoelectric based vibration energy harvesters (PE-VEHs have been developed. The power generation of the reported EM-VEHs is in the range from 0.7 to 1450000 μW. However, the power production by the developed PE-VEHs ranges from 0.6 to 7700 μW. The overall size of most of the bridge VEHs is quite comparable and is in mesoscale. The resonant frequencies of EM-VEHs are on the lower side (0.13 to 27 Hz in comparison to PE-VEHs (1 to 120 Hz. The power densities reported for these bridge VEHs range from 0.01 to 9539.5 μW/cm3 and are quite enough to operate most of the commercial WASNs.

Fatigue Testing of Dental Bridges on Selected Examples

Directory of Open Access Journals (Sweden)

Urban Dariusz

2017-03-01

Full Text Available The paper presents example tests of the functional quality of selected designs of dental bridges. These were: porcelain bridges on a metal base (cobalt based alloy, porcelain bridges on a zirconia base (zirconia ceramic – Zirkon Zahn, and full zirconia bridges (Zirkon Zahn. For the purpose of the study, durability of bridges in cyclic fatigue testing was adopted as a measure of their quality. The tests were carried out on a Zwick Roell Z010 universal testing machine. They consisted in cyclic loading and unloading of dental bridges mounted on gypsum models at a loading force of F= 400 [N] and a frequency of load of f= 1 [Hz]. Each bridge was subjected to a cycle of 7200 loads. The results show that there are no significant differences in the functional quality of the bridges.

Vehicle - Bridge interaction, comparison of two computing models

Science.gov (United States)

Melcer, Jozef; Kuchárová, Daniela

2017-07-01

The paper presents the calculation of the bridge response on the effect of moving vehicle moves along the bridge with various velocities. The multi-body plane computing model of vehicle is adopted. The bridge computing models are created in two variants. One computing model represents the bridge as the Bernoulli-Euler beam with continuously distributed mass and the second one represents the bridge as the lumped mass model with 1 degrees of freedom. The mid-span bridge dynamic deflections are calculated for both computing models. The results are mutually compared and quantitative evaluated.

Seismic Passive Control of Cable-Stayed Bridges

Directory of Open Access Journals (Sweden)

Hosam-Eddin M. Ali

1995-01-01

Full Text Available A three-dimensional modeling procedure is proposed for cable-stayed bridges with rubber, steel, and lead energy dissipation devices. The passive control technique is investigated by considering the response of bridge models with and without energy dissipation devices. The impact of various design parameters on the seismic response of current and future bridge designs is studied. Appropriate locations and properties of the passive devices can achieve better performance for cable-stayed bridges by balancing the significant reduction in earthquake-induced forces against tolerable displacements. Proper design of passive systems can help provide solutions for retro-fitting some existing bridges.

Istanbul Bridge Conference 2014

CERN Document Server

Gülkan, Polat; Mahmoud, Khaled

2016-01-01

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

Estimating the Exchange Rate Pass-Through to Prices in Mexico

OpenAIRE

Josué Fernando Cortés Espada

2013-01-01

This paper estimates the magnitude of the exchange rate pass-through to consumer prices in Mexico. Moreover, it analyzes if the pass-through dynamics have changed in recent years. In particular, it uses a methodology that generates results consistent with the hierarchy implicit in the cpi. The results suggest that the exchange rate pass-through to the general price level is low and not statistically significant. However, the pass-through is positive and significant for goods prices. Furthermo...

A Polish approach to FRP bridges

Science.gov (United States)

Siwowski, Tomasz; Rajchel, Mateusz

2017-12-01

The paper presents initial results of a new approach to FRP composite bridge construction that is presently being developed and tested in Poland. The concept combines lightweight concrete with FRP composites to create a durable highly optimised structure. The paper describes the bridge system itself and presents the research results on its development. The basic design is presented together with research results on its development: FEM analysis and a range of static test results of full-scale bridge beam experiments. The paper finishes with some test results of a full scale bridge that was constructed near Rzeszow in December 2015.

Virginia Bridge Information Systems Laboratory.

Science.gov (United States)

2014-06-01

This report presents the results of applied data mining of legacy bridge databases, focusing on the Pontis and : National Bridge Inventory databases maintained by the Virginia Department of Transportation (VDOT). Data : analysis was performed using a...

Teaching Strategies for the Forearm Pass in Volleyball

Science.gov (United States)

Casebolt, Kevin; Zhang, Peng; Brett, Christine

2014-01-01

This article shares teaching strategies for the forearm pass in the game of volleyball and identifies how they will help students improve their performance and development of forearm passing skills. The article also provides an assessment rubric to facilitate student understanding of the skill.

Reliability Assessment of Concrete Bridges

DEFF Research Database (Denmark)

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

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

Complex Testing of the Bridges

Directory of Open Access Journals (Sweden)

Savić Adrijana

2016-01-01

Full Text Available This article describes the process of examining bridges. AB road bridge, founded on the columns by the Karpoš system and damaged due to erosive action of the river, is given as an example. The first tests of the bridge are conducted on the impact load of V 300, because of the appearance of longitudinal cracks. The results of the columns testing are presented in this paper, as well as the rehabilitation measures thus increasing the load capacity of the column.

Calculation of trajectory parameters of long pass in basketball.

Directory of Open Access Journals (Sweden)

Charikova K.M.

2011-08-01

Full Text Available Values of a ball's flight trajectory parameters depending on a distance of long pass, a corner of a ball's start and height of a throwing point are submitted in article. Coordinates of reference points installation for training to long pass with an optimum trajectory of a ball's flight are designed. Requirements to simulators design are determined. Corners of ball's long pass performance in various game situations are recommended.

ICRF heating of passing ions in TMX-U

International Nuclear Information System (INIS)

Molvik, A.W.; Dimonte, G.; Barter, J.; Campbell, R.; Cummins, W.F.; Falabella, S.; Ferguson, S.W.; Poulsen, P.

1986-04-01

By placing ion-cyclotron resonant frequency (ICRF) antennas on both sides of a midplane gas-feed system in the central cell of the Tandem Mirror Experiment-Upgrade (TMX-U), our results have improved in the following areas: (a) The end losses out both ends show a factor of 3 to 4 increase in passing-ion temperatures and a factor of 2 to 3 decrease in passing-ion densities. (b) The passing-ion heating is consistent with Monte Carlo predictions. (c) The plasma density can be sustained by ICRF plus gas fueling as observed on other experiments

Final Environmental Assessment, Horse Creek Bridge Replacement

Science.gov (United States)

2010-10-01

existing bridge pipes that have failed and replace the failed structure with a new, prefabricated pedestrian bridge within the original bridge footprint...vehicles, nor designed for support of standard passenger vehicle loads. The bridge would be a single prefabricated unit consisting of a steel grate...placed on new concrete abutments built on the existing foundations on the creek banks, and put in place by a crane operating from the vehicle parking

Stabilizer for seismically exposed bridge cranes

International Nuclear Information System (INIS)

Engelke, M.; Kuhr, H.

1982-01-01

The invention concerns a stabilizer for seismically exposed bridge cranes in reactor buildings. The trolley and the crane bridge are fitted with the stabilizer consisting of a bipartite safety catch which is connected with a joint and able to take up the vertical loads during an earthquake. This stabilizer is suitable for all kinds of bridge cranes operated in seismically active regions

SURGERY OF SYMPTOMATIC MYOCARDIAL BRIDGING

Directory of Open Access Journals (Sweden)

N. Maghamipour N. Safaei

2007-06-01

Full Text Available Myocardial bridging with systolic compression of the left anterior descending coronary artery (LAD may be associated with myocardial ischemia. In symptomatic myocardial bridging unresponsive to medical treatment, surgical unroofing of the left LAD can be performed. Little information is available about the long-term prognosis of patients with this coronary anomaly after the surgical unroofing, so we decided to evaluate the result of this operation. A total of 26 patients underwent surgical unroofing of myocardial bridging. Patients had a myocardial bridge of at least 3 cm in length in the middle of LAD and with more than 70% compression during systole. Unroofing was performed with cardiopulmonary bypass in 16 and with off pump technique in 10 patients. In 6 patients repeat angiographies for control of myotomy were done. In one of them a nonsignificant 20% narrowing was seen. Postoperative scintigraphic and angiographic studies demonstrated restoration of coronary flow and myocardial perfusion without residual myocardial bridges under beta-stimulation in 24 patients. Two patients had residual narrowing. With off pump technique, 1 patient had perforation of the right ventricle and 1 patient underwent reoperation because of incomplete unroofing during the first operation. None of the patients with cardiopulmonary bypass technique had residual chest pain or other complications. Surgical unroofing of myocardial bridging with the aid of cardiopulmonary bypass is a safe and easy procedure with low operative risk and with excellent functional results.

Microwave Josephson generation in thin film superconducting bridges

International Nuclear Information System (INIS)

Gubankov, V.N.; Koshelets, V.P.; Ovsyannikov, G.A.

1975-01-01

Thin-film bridges have some advantage over other types of superconducting weak links: good definition of electromagnetic parameters and of weak region geometry. Up to now Josephson properties of bridges have been investigated by using indirect methods (the effect of magnetic field on the critical current I 0 , the bridge behavior in a microwave field, etc.). Direct experimental observation of Josephson radiation from autonomous thin film bridges is reported. Microwave radiation in tin bridges of 'variable' thickness has been investigated where the thickness of the film forming the bridge is far less than the thickness of the bank films. (Auth.)

Floating liquid bridge charge dynamics

Science.gov (United States)

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

2016-01-01

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

An empirical study of exchange rate pass-through in China

Directory of Open Access Journals (Sweden)

Jin Xiaowen

2012-01-01

Full Text Available This paper seeks to estimate exchange rate pass-through in China and investigate its relationship with monetary policy. Linear and VAR models are applied to analyze robustness. The linear model shows that, over the long run, a 1% appreciation of NEER causes a decline in the CPI inflation rate of 0.132% and PPI inflation rate of 0.495%. The VAR model supports the results of the linear model, suggesting a fairly low CPI pass-through and relatively higher PPI pass-through. Furthermore, this paper finds that, with the fixed exchange rate regime, CPI pass-through remains higher. The exchange rate regimes influence on CPI pass through, combined with the fact that appreciation diminishes inflation, suggests that the Chinese government could pursue a more flexible exchange rate policy. In addition, reasons for low exchange rate pass-through for CPI are analyzed. The analysis considers price control, basket and weight of Chinese price indices, distribution cost, and imported and non-tradable share of inputs.

Field performance of timber bridges. 11, Spearfish Creek stress-laminated box-beam bridge

Science.gov (United States)

J. P. Wacker; M. A. Ritter; K. Stanfill-McMillan

The Spearfish Creek bridge was constructed in 1992 in Spearfish, South Dakota. It is a single-span, stress-laminated, box-beam superstructure. Performance of the bridge is being monitored for 5 years, beginning at installation. This report summarizes results for the first 3-1/2 years of monitoring and includes information on the design, construction, and field...

Estimating bridge stiffness using a forced-vibration technique for timber bridge health monitoring

Science.gov (United States)

James P. Wacker; Xiping Wang; Brian Brashaw; Robert J. Ross

2006-01-01

This paper describes an effort to refine a global dynamic testing technique for evaluating the overall stiffness of timber bridge superstructures. A forced vibration method was used to measure the frequency response of several simple-span, sawn timber beam (with plank deck) bridges located in St. Louis County, Minnesota. Static load deflections were also measured to...

Design aids of NU I-girders bridges.

Science.gov (United States)

2010-05-01

Precast prestressed concrete I-Girder bridges have become the most dominant bridge system in the United States. In the early design : stages, preliminary design becomes a vital first step in designing an economical bridge. Within the state of Nebrask...

Faster bridge construction using precast substructures : brief.

Science.gov (United States)

2011-07-01

Bridge replacement often requires road closures and detours that frustrate road users. It remains a key goal of Wisconsin DOT to reduce construction-related road use interruptions. This will be a challenge with bridges: Bridge inspections in 2007 ide...

BUILDING "BRIDGES" WITH QUALITY ASSURANCE

Science.gov (United States)

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

Inspection Based Evaluation of a Danish Road Bridge

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

In this paper it is shown how an inspection-based evaluation of a Danish road bridge may be performed using the BRIDGE1 and BRIDGE2 bridge management systems produced within the EC-supported research programme "Assessment of Performance and Optimal Strategies for Inspection and Maintenance...

Violin Bridge Mobility Analysis under In-Plane Excitation

Directory of Open Access Journals (Sweden)

Cheng-Zhong Zhang

2013-11-01

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

Violin bridge mobility analysis under in-plane excitation.

Science.gov (United States)

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

2013-11-08

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

Monitoring bridge scour using fiber optic sensors.

Science.gov (United States)

2015-04-01

The scouring process excavates and carries away materials from the bed and banks of streams, and from : around the piers and abutments of bridges. Scour undermines bridges and may cause bridge failures due to : structural instability. In the last 30 ...

Covered Bridge Security Manual

Science.gov (United States)

Brett Phares; Terry Wipf; Ryan Sievers; Travis Hosteng

2013-01-01

The design, construction, and use of covered timber bridges is all but a lost art in these days of pre-stressed concrete, high-performance steel, and the significant growth both in the volume and size of vehicles. Furthermore, many of the existing covered timber bridges are preserved only because of their status on the National Registry of Historic Places or the...

Public response to bridge colors.

Science.gov (United States)

1973-01-01

To determine people's reactions to bridges painted in colors as white, yellow, green, blue, red, brown, black, and aluminum, two test bridges were selected in Charlottesville, Virginia. One was painted a different color each month and the other was k...

A First-Order One-Pass CPS Transformation

DEFF Research Database (Denmark)

Danvy, Olivier; Nielsen, Lasse Reichstein

2001-01-01

We present a new transformation of λ-terms into continuation-passing style (CPS). This transformation operates in one pass and is both compositional and first-order. Previous CPS transformations only enjoyed two out of the three properties of being first-order, one-pass, and compositional......, but the new transformation enjoys all three properties. It is proved correct directly by structural induction over source terms instead of indirectly with a colon translation, as in Plotkin's original proof. Similarly, it makes it possible to reason about CPS-transformed terms by structural induction over...... source terms, directly.The new CPS transformation connects separately published approaches to the CPS transformation. It has already been used to state a new and simpler correctness proof of a direct-style transformation, and to develop a new and simpler CPS transformation of control-flow information....

A First-Order One-Pass CPS Transformation

DEFF Research Database (Denmark)

Danvy, Olivier; Nielsen, Lasse Reichstein

2003-01-01

We present a new transformation of λ-terms into continuation-passing style (CPS). This transformation operates in one pass and is both compositional and first-order. Previous CPS transformations only enjoyed two out of the three properties of being first-order, one-pass, and compositional......, but the new transformation enjoys all three properties. It is proved correct directly by structural induction over source terms instead of indirectly with a colon translation, as in Plotkin's original proof. Similarly, it makes it possible to reason about CPS-transformed terms by structural induction over...... source terms, directly.The new CPS transformation connects separately published approaches to the CPS transformation. It has already been used to state a new and simpler correctness proof of a direct-style transformation, and to develop a new and simpler CPS transformation of control-flow information....

Salt bridge as a gatekeeper against partial unfolding.

Science.gov (United States)

Hinzman, Mark W; Essex, Morgan E; Park, Chiwook

2016-05-01

Salt bridges are frequently observed in protein structures. Because the energetic contribution of salt bridges is strongly dependent on the environmental context, salt bridges are believed to contribute to the structural specificity rather than the stability. To test the role of salt bridges in enhancing structural specificity, we investigated the contribution of a salt bridge to the energetics of native-state partial unfolding in a cysteine-free version of Escherichia coli ribonuclease H (RNase H*). Thermolysin cleaves a protruding loop of RNase H(*) through transient partial unfolding under native conditions. Lys86 and Asp108 in RNase H(*) form a partially buried salt bridge that tethers the protruding loop. Investigation of the global stability of K86Q/D108N RNase H(*) showed that the salt bridge does not significantly contribute to the global stability. However, K86Q/D108N RNase H(*) is greatly more susceptible to proteolysis by thermolysin than wild-type RNase H(*) is. The free energy for partial unfolding determined by native-state proteolysis indicates that the salt bridge significantly increases the energy for partial unfolding by destabilizing the partially unfolded form. Double mutant cycles with single and double mutations of the salt bridge suggest that the partially unfolded form is destabilized due to a significant decrease in the interaction energy between Lys86 and Asp108 upon partial unfolding. This study demonstrates that, even in the case that a salt bridge does not contribute to the global stability, the salt bridge may function as a gatekeeper against partial unfolding that disturbs the optimal geometry of the salt bridge. © 2016 The Protein Society.

Static thermo-optic instability in double-pass fiber amplifiers

DEFF Research Database (Denmark)

Lægsgaard, Jesper

2016-01-01

A coupled-mode formalism, earlier used to describe transverse mode instabilities in single-pass optical fiber amplifiers, is extended to the case of double-pass amplifiers. Contrary to the single-pass case, it is shown that the thermo-optic nonlinearity can couple light at the same frequency...... between the LP01 and LP11 modes, leading to a static deformation of the output beam profile. This novel phenomenon is caused by the interaction of light propagating in either direction with thermo-optic index perturbations caused by light propagating in the opposite direction. The threshold power...... for the static deformation is found to be several times lower than what is typically found for the dynamic modal instabilities observed in single-pass amplifiers. (C) 2016 Optical Society of America...

Effect of passing vessels on a moored ship

Energy Technology Data Exchange (ETDEWEB)

Lean, G H; Price, W A

1977-11-01

The effect of passing vessels on a moored ship was investigated by a series of model tests carried out at the Hydraulics Research Station for the Esso Petroleum Co. Ltd., transportation department in connection with their oil jetty at Milford Haven. A main conclusion was that the forces appeared to be due to the pressure gradients associated with the pattern of flow that accompanies the passing ship rather than with the wave system. Slack lines are to be avoided, and some relief in maximum line loads can be achieved by increasing the pretension. The results included the effects of passing vessel speed and ship clearance and draft.

IceBridge: Bringing a Field Campaign Home

Science.gov (United States)

Woods, J.; Beck, J.; Bartholow, S.

2015-12-01

IceBridge, a six-year NASA mission, is the largest airborne survey of Earth's polar ice ever flown. It will yield an unprecedented three-dimensional view of Arctic and Antarctic ice sheets, ice shelves and sea ice. These flights will provide a yearly, multi-instrument look at the behavior of the rapidly changing features of the Greenland and Antarctic ice. Data collected during IceBridge will help scientists bridge the gap in polar observations between NASA's Ice, Cloud and Land Elevation Satellite (ICESat) -- in orbit since 2003 -- and ICESat-2, planned for 2017. ICESat stopped collecting science data in 2009, making IceBridge critical for ensuring a continuous series of observations. IceBridge will use airborne instruments to map Arctic and Antarctic areas once a year at a minimum, with new campaigns being developed during the Arctic melt season. IceBridge flights are conducted in the spring and summer for the Arctic and in the fall over Antarctica. Other smaller airborne surveys around the world are also part of the IceBridge campaign. IceBridge actively engages the public and educators through a variety of outlets ranging from communications strategies through social media outlets, to larger organized efforts such as PolarTREC. In field activities include blog posts, photo updates, in flight chat sessions, and more intensive live events to include google hangouts, where field team members can interact with the public during a scheduled broadcast. The IceBridge team provides scientists and other team members with the training and support to become communicators in their own right. There is an exciting new initiative where IceBridge will be collaborating with Undergraduate and Graduate students to integrate the next generation of scientists and communicators into the Science Teams. This will be explored through partnerships with institutions that are interested in mentoring through project based initiatives.

The Pass-Through of Exchange Rate Changes to Import Prices

OpenAIRE

Ketelsen, Uwe; Kortelainen, Mika

1996-01-01

In this paper we analyze the empirical relevance of exchange rate pass-through for Finland, Sweden and Denmark during the period 1980–1994. Further, we attempt to determine if there has been a structural change in the pass-through relationship in the1990s. We find that about half the changes in exchange rates and world prices are passed through to import prices within one year, and three-quarters of such changes are passed through to import prices in two years. Moreover, there are no major di...

Bridge Deterioration Prediction Model Based On Hybrid Markov-System Dynamic

Directory of Open Access Journals (Sweden)

Widodo Soetjipto Jojok

2017-01-01

Full Text Available Instantaneous bridge failure tends to increase in Indonesia. To mitigate this condition, Indonesia’s Bridge Management System (I-BMS has been applied to continuously monitor the condition of bridges. However, I-BMS only implements visual inspection for maintenance priority of the bridge structure component instead of bridge structure system. This paper proposes a new bridge failure prediction model based on hybrid Markov-System Dynamic (MSD. System dynamic is used to represent the correlation among bridge structure components while Markov chain is used to calculate temporal probability of the bridge failure. Around 235 data of bridges in Indonesia were collected from Directorate of Bridge the Ministry of Public Works and Housing for calculating transition probability of the model. To validate the model, a medium span concrete bridge was used as a case study. The result shows that the proposed model can accurately predict the bridge condition. Besides predicting the probability of the bridge failure, this model can also be used as an early warning system for bridge monitoring activity.

TRT Barrel milestones passed

CERN Multimedia

Ogren, H

2004-01-01

The barrel TRT detector passed three significant milestones this spring. The Barrel Support Structure (BSS) was completed and moved to the SR-1 building on February 24th. On March 12th the first module passed the quality assurance testing in Building 154 and was transported to the assembly site in the SR-1 building for barrel assembly. Then on April 21st the final production module that had been scanned at Hampton University was shipped to CERN. TRT Barrel Module Production The production of the full complement of barrel modules (96 plus 9 total spares) is now complete. This has been a five-year effort by Duke University, Hampton University, and Indiana University. Actual construction of the modules in the United States was completed in the first part of 2004. The production crews at each of the sites in the United States have now completed their missions. They are shown in the following pictures. Duke University: Production crew with the final completed module. Indiana University: Module producti...

Quantum Bidding in Bridge

Science.gov (United States)

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

2014-04-01

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

Re-Assessment of Concrete Bridges

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

In this paper two aspects of re-assessment of the reliability of concrete bridges are discussed namely modelling of the corrosion of reinforcement and updating of uncertain variables. The main reason for deterioration of concrete bridges is corrosion of the reinforcement. Therefore, modelling...

Rapid replacement/construction of bridges.

Science.gov (United States)

2012-11-01

Bridges are a key element of the transportation system because they control system capacity and are normally built at : the highest cost to the system. Once a bridge reaches its useful design service life, it needs to be replaced or : reconstructed i...

PASS Student Leader and Mentor Roles: A Tertiary Leadership Pathway

Science.gov (United States)

Skalicky, Jane; Caney, Annaliese

2010-01-01

In relation to developing leadership skills during tertiary studies, this paper considers the leadership pathway afforded by a Peer Assisted Study Sessions (PASS) program which includes the traditional PASS Leader role and a more senior PASS Mentor role. Data was collected using a structured survey with open-ended questions designed to capture the…

Regenerative beam breakup in multi-pass electron accelerators

International Nuclear Information System (INIS)

Vetter, A.M. Jr.

1980-01-01

Important electron coincidence experiments in the 1 to 2 GeV range require electron beams of high intensity and high duty factor. To provide such beams, multi-pass electron accelerator systems are being developed at many laboratories. The beam current in multi-pass electron machines is limited by bean breakup which arises from interaction of the electron beam with deflection modes of the accelerator structure. Achieving high beam intensity (50 to 100 μA) will require detailed understanding and careful control of beam breakup phenomena, and is the subject of this thesis. The TM 11 -like traveling wave theory is applied to obtain a physical understanding of beam-mode interactions and the principles of focussing in simple two-pass systems, and is used as a basis for general studies of the dependence of starting current on accelerator parameters in systems of many passes. The concepts developed are applied in analyzing beam breakup in the superconducting recyclotron at Stanford. Measurements of beam interactions with selected breakup modes are incorporated in a simple model in order to estimate relative strengths of breakup modes and to predict starting currents in five-pass operation. The improvement over these predicted currents required in order to obtain 50 to 100 μA beams is shown to be achievable with a combination of increased breakup mode loading and improved beam optics

33 CFR 118.80 - Lights on bascule bridges.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lights on bascule bridges. 118.80 Section 118.80 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.80 Lights on bascule bridges. (a) Lift span lights. Each lift span of...

Precast Pearl-Chain concrete arch bridges

DEFF Research Database (Denmark)

Halding, Philip Skov; Hertz, Kristian Dahl; Schmidt, Jacob Wittrup

2015-01-01

A Pearl-Chain Bridge is a closed-spandrel arch bridge consisting of a number of straight pre-fabricated so called Super-Light Deck elements put together in an arch shape by post-tensioning cables. Several Pearl-Chain arches can be positioned adjacent to each other by a crane to achieve a bridge...... of a desired width. On top of the arch is a filling material to level out the surface of the above road. The filling only transfers vertical loads to the arch. The geometry and material properties of Super-Light Decks are presented, and we refer to several fullscale tests of Pearl-Chain arches where...... the technology was used. We also study other important components and details in the Pearl-Chain Bridge concept and review the effects of different types of loads. A theoretical case study of a circular 30 m span Pearl-Chain Bridge is presented showing the influence of a number of parameters: The number of post...

Statistics of Epidemics in Networks by Passing Messages

Science.gov (United States)

Shrestha, Munik Kumar

Epidemic processes are common out-of-equilibrium phenomena of broad interdisciplinary interest. In this thesis, we show how message-passing approach can be a helpful tool for simulating epidemic models in disordered medium like networks, and in particular for estimating the probability that a given node will become infectious at a particular time. The sort of dynamics we consider are stochastic, where randomness can arise from the stochastic events or from the randomness of network structures. As in belief propagation, variables or messages in message-passing approach are defined on the directed edges of a network. However, unlike belief propagation, where the posterior distributions are updated according to Bayes' rule, in message-passing approach we write differential equations for the messages over time. It takes correlations between neighboring nodes into account while preventing causal signals from backtracking to their immediate source, and thus avoids "echo chamber effects" where a pair of adjacent nodes each amplify the probability that the other is infectious. In our first results, we develop a message-passing approach to threshold models of behavior popular in sociology. These are models, first proposed by Granovetter, where individuals have to hear about a trend or behavior from some number of neighbors before adopting it themselves. In thermodynamic limit of large random networks, we provide an exact analytic scheme while calculating the time dependence of the probabilities and thus learning about the whole dynamics of bootstrap percolation, which is a simple model known in statistical physics for exhibiting discontinuous phase transition. As an application, we apply a similar model to financial networks, studying when bankruptcies spread due to the sudden devaluation of shared assets in overlapping portfolios. We predict that although diversification may be good for individual institutions, it can create dangerous systemic effects, and as a result

Determination of in-situ strength on selected bridge element concrete girder and slab of Nagtahan bridge using rebound hammer test

International Nuclear Information System (INIS)

Uy, Bernadette Betsy B.; Banaga, Renato T.

2013-01-01

This study examined the extent of the damage due to fire on the affected areas of the bridge structure. The need to assess the damage of the Nagtahan Bridge is very useful to provide appropriate measures in the repair or in the reinforcement of the bridge, hence will ensure its strength and integrity. The study included two (2) spans of the bridge deck/slab with specific locations of the bridge that were subjected for testing. The Rebound Hammer was used as a preliminary test in evaluating the bridge condition. Its capability is to assess the in-place uniformity of concrete, to delineate regions in a structure of poor quality or deteriorated concrete, and to estimate the in-place strength; and ultimately, for relative comparison between the different structures of the bridge. With the use of the NDT Rebound Hammer Test, the researchers were able to determine whether or not the in-situ strength of the bridge's concrete has been weakened due to fire. The DPW-Standard Specification is the government acceptable manual, containing the acceptance criteria, used as the basis for standard construction procedures in the department.(author)

Future Trends in Reliability-Based Bridge Management

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

Future bridge management systems will be based on simple stochastic models predicting the residual strength of structural elements. The current deterministic management systems are not effective in optimizing e.g. the life cycle cost of a bridge or a system of bridges. A number of important factors...

Planning of Tatara Bridge. Chodai shachokyo-Tataraohashi-no keikaku gaiyo

Energy Technology Data Exchange (ETDEWEB)

Okukawa, A. (Honshu-Shikoku Bridge Authority, Tokyo (Japan))

1991-12-05

The outline of the Tatara Bridge is given to introduce the features of the entire structural system and fundamental problems concerning the construction of the huge cable stayed bridge. The central span of the bridge is 890m. The topography and geological features of the bridging point are reviewed, and social conditions such as being in a national park, safety for sailing, etc. are taken into consideration for various technological studies on the construction of the huge bridge. Bridge piers are provided in the side spans and appropriate counter weight is loaded to design a more economical bridge which is more suitable for the topography as compared with a suspension bridge. The cable stayed bridge requires no anchorage which is necessary for a suspension bridge with very little topological alteration, and an excellent result is obtained both in cost and term of construction as compared with a suspension bridge. The rigidity of the cable stayed bridge is high, and the stability of the resistance to wind of the structure is also very satisfactory. As a result, it is concluded that the bridge can be designed and constructed using currently available technologies, and a cable stayed bridge is selected in August, 1990 as the type for the Tatara Bridge. 9 figs., 1 tab.

33 CFR 118.85 - Lights on vertical lift bridges.

Science.gov (United States)

2010-07-01

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

Applicability estimation of flowmeter logging for detecting hydraulic pass

International Nuclear Information System (INIS)

Miyakawa, Kimio; Tanaka, Yasuji; Tanaka, Kazuhiro

1997-01-01

Estimation of the hydraulic pass governing hydrogeological structure contributes significantly to the siting HLW repository. Flowmeter logging can detect hydraulic passes by measuring vertical flow velocity of groundwater in the borehole. We reviewed application of this logging in situ. The hydraulic pass was detected with combination of ambient flow logging, with pumping and/or injecting induced flow logging. This application showed that the flowmeter logging detected hydraulic passes conveniently and accurately compared with other hydraulic tests. Hydraulic conductivity by using flowmeter logging was assessed above 10 -6 m/sec and within one order from comparison with injection packer tests. We suggest that appropriate application of the flowmeter logging for the siting is conducted before hydraulic tests because test sections and monitoring sections are decided rationally for procurement of quantitative hydraulic data. (author)

TMACS test procedure TP012: Panalarm software bridge

International Nuclear Information System (INIS)

Washburn, S.J.

1994-01-01

This Test Procedure addresses the testing of the functionality of the Tank Monitor and Control System (TMACS) Panalarm bridge software. The features to be tested are: Bridge Initialization Options; Bridge Communication; Bridge Performance; Testing Checksum Errors; and Testing Command Reject Errors. Only the first three could be tested; the last two have been deferred to a later date

Running Safety of Trains under Vessel-Bridge Collision

Directory of Open Access Journals (Sweden)

Yongle Li

2015-01-01

Full Text Available To optimize the sensor placement of the health monitoring system, the dynamic behavior of the train-bridge system subjected to vessel-collision should be studied in detail firstly. This study thus focuses on the characteristics of a train-bridge system under vessel-bridge collision. The process of the vessel-bridge collision is simulated numerically with a reliable finite element model (FEM. The dynamic responses of a single car and a train crossing a cable-stayed bridge are calculated. It is shown that the collision causes significant increase of the train’s lateral acceleration, lateral wheelset force, wheel unloading rate, and derailment coefficient. The effect of the collision on the train’s vertical acceleration is much smaller. In addition, parametric studies with various train’s positions, ship tonnage, and train speed are performed. If the train is closer to the vessel-bridge collision position or the ship tonnage is larger, the train will be more dangerous. There is a relatively high probability of running danger at a low speed, resulting from longer stay of the train on the bridge. The train’s position, the ship tonnage, and the train speed must be considered when determining the most adverse conditions for the trains running on bridges under vessel-bridge collision.

Integrated Cu-based TM-pass polarizer using CMOS technology platform

KAUST Repository

Ng, Tien Khee

2010-01-01

A transverse-magnetic-pass (TM-pass) copper (Cu) polarizer is proposed and analyzed using the previously published two-dimensional Method-of-Lines beam-propagation model. The proposed polarizer exhibits a simulated high-pass filter characteristics, with TM0 and TE0 mode transmissivity of >70% and <5%, respectively, in the wavelength regime of 1.2-1.6 μm. The polarization extinction ratio (PER) given by 10 log10 (PTM0)/(PTE0) is +11.5 dB across the high-pass wavelength regime. To the best of the authors\\' knowledge, we report here the smallest footprint CMOS-platform compatible TM-polarizer.

77 FR 31725 - Safety Zone; Belle Pass Dredge Operations, Belle Pass, Mile Marker 1.0 to Mile Marker (−0.2...

Science.gov (United States)

2012-05-30

... Environmental Health Risks and Safety Risks. This rule is not an economically significant rule and does not create an environmental risk to health or risk to safety that may disproportionately affect children. 11...-AA00 Safety Zone; Belle Pass Dredge Operations, Belle Pass, Mile Marker 1.0 to Mile Marker (-0.2), Port...

Fatigue test on aluminium bridges

NARCIS (Netherlands)

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

2005-01-01

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

Vulnerability of bridges to fire

DEFF Research Database (Denmark)

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

2012-01-01

Even if recent effort in developing methodology and measures for design structures against fire and explosions has been mostly focused on buildings, bridges can also be very sensitive to those actions, as witnesses by some recent bridge accidents, which caused major economic losses and also endan...

Bridge employment after early retirement: a bridge to better postretirement well-being of older adults?

NARCIS (Netherlands)

Dingemans, E.

2012-01-01

Using a retirement arrangement does not necessarily mean that people retire fulltime. The phenomenon of bridge employment, already studied in the US, becomes increasingly popular among older adults in the Netherlands. The question is to what extent bridge employment can be beneficial for well-being

A Simple and Universal Resistive-Bridge Sensors Interface

Directory of Open Access Journals (Sweden)

Sergey Y. YURISH

2011-02-01

Full Text Available Resistive-bridge sensors are widely used in various sensor systems. There are many sensor signal conditioners from different manufacturers for such sensing elements. However, no one existing on the modern market integrated converter for resistive bridge sensors can work with both: resistive-bridge sensing elements and resistive-to-frequency and -duty-cycle converters’ outputs. A proposed and described in the article universal interface for resistive-bridge sensing elements and bridge-output-to-frequency and/or duty cycle converters based on the designed Universal Sensors and Transducers Interface (USTI integrated. It is based on a simple, cost effective three-point measuring technique and does not require any additional active components. The USTI IC is realized in a standard CMOS technology. The active supply current at operating voltage +4.5 V and clock frequency 20 MHz is not more than 9.5 mA This paper reports experimental results with a strain gauges bridge emulator and differential pressure resistive bridge sensor SX30GD2.

Prestressed concrete cable-stayed bridge; PC shachokyo `Tajiri sky bridge` no seko

Energy Technology Data Exchange (ETDEWEB)

Kaida, Y.; Tsujino, F. [Osaka Prefectural Government Office, Osaka (Japan); Yamamoto, T.; Hishiki, Y.; Saito, K.

1995-01-30

The outline on the execution of PC cable-stayed bridge `Tajiri Sky Bridge` which was built at the opposite coast of Kansai International Airport was reported. This bridge is a double-sided suspension PC cable-stayed bridge with a tower height of 93.6 m having a main beam which is 26.3 m wide, featuring H-type main tower with one side beam, a smooth main beam structure, the leg top part with a large section, etc. A large-capacity factory manufacturing type non-grout cable with a pull strength of 1,900 ton class was adopted for the diagonal bracing. The leg top part is in a massive concrete structure so that, for avoiding the crack of cement due to temperature, a low heat build-up furnace cement was adopted, the water reducing agent was used, pre-cooling and side-clamping PC steel material were adopted and moderate pre-stress was introduced. In the execution of the connection part of the main beam, for preventing the deflection fluctuation due to the change of the main beam/main tower/diagonal bracing due to temperature and vibration due to wind, the earth anchor was used to tentatively fix the extended part. During execution, the wind velocity was strong reaching 25 m/s, which did not produce any problems. 1 ref., 24 figs., 3 tabs.

BRIDGES for Young Adolescents in North Dakota.

Science.gov (United States)

Harris, Mary McDonnell

The BRIDGES Project was initiated to explore ways for North Dakota to provide young people with stronger bridges from childhood to adulthood. This report summarizes recommendations of the 1990-91 Governor's Task Force on Early Adolescence. The recommendations concern practical actions for the building of bridges by the following groups: (1)…

Lifetime Reliability Assessment of Concrete Slab Bridges

DEFF Research Database (Denmark)

Thoft-Christensen, Palle

A procedure for lifetime assesment of the reliability of short concrete slab bridges is presented in the paper. Corrosion of the reinforcement is the deterioration mechanism used for estimating the reliability profiles for such bridges. The importance of using sensitivity measures is stressed....... Finally the produce is illustrated on 6 existing UK bridges....

Right Ventricular Ejection Fraction using ECG-Gated First Pass Cardioangiography

Energy Technology Data Exchange (ETDEWEB)

Moon, Young Hee; Lee, Hae Giu; Lee, Sung Yong; Park, Suk Min; Chung, Soo Kyo; Yim, Jeong Ik; Bahk, Yong Whee; Shinn, Kyung Sub; Kim, Young Gyun; Kwon, Soon Seog [Catholic University College of Medicine, Seoul (Korea, Republic of)

1993-03-15

Radionuclide cardioangiography has been widely applied and has played major roles in moninvasive assessment of cardiac function. Three techniques, first-pass gated first and gated equilibrium methods have commonly been used to evaluate right ventricular ejection fraction which usually abnormal in the patients with cardiopulmonary disease. It has been known that the gated first pass method is most accurate method among the three techniques in assessment of fight ventricular ejection fraction. The radionuclide right ventricular ejection fraction values were determined in 13 normal subjects and in 15 patients with chronic obstructive pulmonary disease by the gated first pass method and compared with those of the first pass method because there has been no published data of fight ejection fraction by the gated first pass method were compared with the defects from the pulmonary function test performed in the patients with chronic obstructive pulmomary disease. The results were as follows; 1) The values of fight ventricular ejection fraction by the gated first pass method were 50.1 +- 6.1% in normal subjects and 38.5 +- 8.5 in the patients with chronic obstructive pulmonary disease. There was statistically significant difference between the right ventricular ejection fraction of each of the two groups (p<0.05) 2) The right ventricular ejection fraction by the gated first pass method was not linearly correlated ith FEV{sub 1}, VC. DLCO. and FVC as well as P{sub a}O2 and P{sub a}CO2 of the patients with chronic obstructive pulmonary disease. We concluded that right ventricular ejection fraction by the gated first pass method using radionuclide cardioangiography may be useful in clinical assessment of the right ventricular function.

Modeling and analysis of a biomorph piezoelectric energy harvester for railway bridge monitoring

Science.gov (United States)

Li, Jingcheng; Jang, Shinae; Tang, Jiong

2012-04-01

Wireless sensor network is one of prospective methods for railway bridge health monitoring. It has drawn much attention due to the long-term operation and low-maintenance performances. However, how to provide power to wireless sensors is a big issue. In railway health monitoring, the idea of converting ambient vibration energy from the vibration of railway track induced by passing train to electric energy has made it an efficient way for powering the wireless sensor networks. In this paper, a bimorph piezoelectric energy harvester from base excitation was investigated in the laboratory, and the energy output of the bimorph energy harvester was predicted by an equivalent single-degree-of-freedom (SDOF) model. Reasonable results have been found between the tested and predicted data. Based on the theoretical model, further works on optimization of the bimorph piezoelectric energy harvester will be performed in future.

Blind sensor calibration using approximate message passing

International Nuclear Information System (INIS)

Schülke, Christophe; Caltagirone, Francesco; Zdeborová, Lenka

2015-01-01

The ubiquity of approximately sparse data has led a variety of communities to take great interest in compressed sensing algorithms. Although these are very successful and well understood for linear measurements with additive noise, applying them to real data can be problematic if imperfect sensing devices introduce deviations from this ideal signal acquisition process, caused by sensor decalibration or failure. We propose a message passing algorithm called calibration approximate message passing (Cal-AMP) that can treat a variety of such sensor-induced imperfections. In addition to deriving the general form of the algorithm, we numerically investigate two particular settings. In the first, a fraction of the sensors is faulty, giving readings unrelated to the signal. In the second, sensors are decalibrated and each one introduces a different multiplicative gain to the measurements. Cal-AMP shares the scalability of approximate message passing, allowing us to treat large sized instances of these problems, and experimentally exhibits a phase transition between domains of success and failure. (paper)

Linear Fixed-Field Multi-Pass Arcs for Recirculating Linear Accelerators

International Nuclear Information System (INIS)

Morozov, V.S.; Bogacz, S.A.; Roblin, Y.R.; Beard, K.B.

2012-01-01

Recirculating Linear Accelerators (RLA's) provide a compact and efficient way of accelerating particle beams to medium and high energies by reusing the same linac for multiple passes. In the conventional scheme, after each pass, the different energy beams coming out of the linac are separated and directed into appropriate arcs for recirculation, with each pass requiring a separate fixed-energy arc. In this paper we present a concept of an RLA return arc based on linear combined-function magnets, in which two and potentially more consecutive passes with very different energies are transported through the same string of magnets. By adjusting the dipole and quadrupole components of the constituting linear combined-function magnets, the arc is designed to be achromatic and to have zero initial and final reference orbit offsets for all transported beam energies. We demonstrate the concept by developing a design for a droplet-shaped return arc for a dog-bone RLA capable of transporting two beam passes with momenta different by a factor of two. We present the results of tracking simulations of the two passes and lay out the path to end-to-end design and simulation of a complete dog-bone RLA.

33 CFR 165.1187 - Security Zones; Golden Gate Bridge and the San Francisco-Oakland Bay Bridge, San Francisco Bay...

Science.gov (United States)

2010-07-01

... Limited Access Areas Eleventh Coast Guard District § 165.1187 Security Zones; Golden Gate Bridge and the... Golden Gate Bridge and the San Francisco-Oakland Bay Bridge, in San Francisco Bay, California. (b... siren, radio, flashing light, or other means, the operator of a vessel shall proceed as directed. [COTP...

Wind tunnel test of musi VI bridge

Science.gov (United States)

Permata, Robby; Andika, Matza Gusto; Syariefatunnisa, Risdhiawan, Eri; Hermawan, Budi; Noordiana, Indra

2017-11-01

Musi VI Bridge is planned to cross the Musi River in Palembang City, South Sumatera Province, Indonesia. The main span is a steel arch type with 200 m length and side span length is 75 m. Finite element analysis results showed that the bridge has frequency ratio for torsional and heaving mode (torsional frequency/heaving frequency)=1.14. This close to unity value rises concern about aerodynamic behaviour and stability of the bridge deck under wind loading. Sectional static and free vibration wind tunnel test were performed to clarify this phenomena in B2TA3 facility in Serpong, Indonesia. The test followed the draft of Guide of Wind Tunnel Test for Bridges developed by Indonesian Ministry of Public Works. Results from wind tunnel testing show that the bridge is safe from flutter instability and no coupled motion vibration observed. Therefore, low value of frequency ratio has no effect to aerodynamic behaviour of the bridge deck. Vortex-induced vibration in heaving mode occurred in relatively low wind velocity with permissible maximum amplitude value.

Methanol, Ethanol and Propanol in EHD liquid bridging

International Nuclear Information System (INIS)

Fuchs, Elmar C; Wexler, Adam D; Agostinho, Luewton L F; Ramek, Michael; Woisetschläger, Jakob

2011-01-01

When a high-voltage direct-current is applied to two beakers filled with water or polar liquid dielectrica, a horizontal bridge forms between the two beakers. In this work such bridges made of methanol, ethanol, 1-propanol and 2-propanol are investigated with polarimetry and thermography. Whereas methanol, ethanol and 1-propanol bridges become warm like a water bridge, a 2-propanol bridge cools down relative to the surroundings. It is shown how the different stability of the primary and secondary alcoholate ions and the resulting small difference in conductivity between 1-propanol and 2-propanol is responsible for this novel effect.

The shape, stability and breakage of pendant liquid bridges

Science.gov (United States)

Padday, J. F.; Pétré, G.; Rusu, C. G.; Gamero, J.; Wozniak, G.

1997-12-01

Pendant liquid bridges are defined as pendant drops supporting a solid axisymmetric endplate at their lower end. The stability and shape properties of such bridges are defined in terms of the capillary properties of the system and of the mass and radius of the lower free-floating endplate. The forces acting in the pendant liquid bridge are defined exactly and expressed in dimensionless form. Numerical analysis has been used to derive the properties of a given bridge and it is shown that as the bridge grows by adding more liquid to the system a maximum volume is reached. At this maximum volume, the pendant bridge becomes unstable with the length of the bridge increasing spontaneously and irreversibly at constant volume. Finally the bridge breaks with the formation of a satellite drop or an extended thread. The bifurcation and breakage processes have been recorded using a high-speed video camera with a digital recording rate of up to 6000 frames per second. The details of the shape of the bridge bifurcation and breakage for many pendant bridge systems have been recorded and it is shown that satellite drop formation after rupture is not always viscosity dependent. Bifurcation and breakage in simulated low gravity demonstrated that breakage was very nearly symmetrical about a plane through the middle of the pendant bridge.

Seismic response computations for a long span bridge

International Nuclear Information System (INIS)

McCallen, D.B.

1994-01-01

The authors are performing large-scale numerical computations to simulate the earthquake response of a major long-span bridge that crosses the San Francisco Bay. The overall objective of the study is to estimate the response of the bridge to potential large-magnitude earthquakes generated on the nearby San Andreas and Hayward earthquake faults. Generation of a realistic model of the bridge system is complicated by the existence of large pile group foundations that extend deep into soft, saturated clay soils, and by the numerous expansion joints that segment the overall bridge structure. In the current study, advanced, nonlinear, finite element technology is being applied to rigorously model the detailed behavior of the bridge system and to shed light on the influence of the foundations and joints of the bridge

Setting pass scores for clinical skills assessment.

Science.gov (United States)

Liu, Min; Liu, Keh-Min

2008-12-01

In a clinical skills assessment, the decision to pass or fail an examinee should be based on the test content or on the examinees' performance. The process of deciding a pass score is known as setting a standard of the examination. This requires a properly selected panel of expert judges and a suitable standard setting method, which best fits the purpose of the examination. Six standard setting methods that are often used in clinical skills assessment are described to provide an overview of the standard setting process.

Shear evaluation of tapered bridge girder panels with steel corrugated webs near the supports of continuous bridges

OpenAIRE

Zevallos, E.; Hassanein, M.F.; Real Saladrigas, Esther; Mirambell Arrizabalaga, Enrique

2016-01-01

Because of public construction budgets were cut over the last few years, new bridge girders with corrugated webs to reduce the construction costs have become more widely studied and used. In spite that tapered bridge girders with corrugated webs (BGCWs) are used in modern bridges, their shear strength and behaviour rarely exists in literature. Based on available literature, the web of the linearly tapered BGCWs may be divided into three typologies with different structural response to shear f...

Blasting detonators incorporating semiconductor bridge technology

Energy Technology Data Exchange (ETDEWEB)

Bickes, R.W. Jr.

1994-05-01

The enormity of the coal mine and extraction industries in Russia and the obvious need in both Russia and the US for cost savings and enhanced safety in those industries suggests that joint studies and research would be of mutual benefit. The author suggests that mine sites and well platforms in Russia offer an excellent opportunity for the testing of Sandia`s precise time-delay semiconductor bridge detonators, with the potential for commercialization of the detonators for Russian and other world markets by both US and Russian companies. Sandia`s semiconductor bridge is generating interest among the blasting, mining and perforation industries. The semiconductor bridge is approximately 100 microns long, 380 microns wide and 2 microns thick. The input energy required for semiconductor bridge ignition is one-tenth the energy required for conventional bridgewire devices. Because semiconductor bridge processing is compatible with other microcircuit processing, timing and logic circuits can be incorporated onto the chip with the bridge. These circuits can provide for the precise timing demanded for cast effecting blasting. Indeed tests by Martin Marietta and computer studies by Sandia have shown that such precise timing provides for more uniform rock fragmentation, less fly rock, reduce4d ground shock, fewer ground contaminants and less dust. Cost studies have revealed that the use of precisely timed semiconductor bridges can provide a savings of $200,000 per site per year. In addition to Russia`s vast mineral resources, the Russian Mining Institute outside Moscow has had significant programs in rock fragmentation for many years. He anticipated that collaborative studies by the Institute and Sandia`s modellers would be a valuable resource for field studies.

0-6722 : spread prestressed concrete slab beam bridges.

Science.gov (United States)

2014-08-01

The Texas Department of Transportation uses : precast prestressed concrete slab beam bridges for : shorter-span bridges of approximately 3050 ft in : length. Conventional slab beam bridges have slab : beams placed immediately adjacent to one anoth...

Pass-fail grading: laying the foundation for self-regulated learning.

Science.gov (United States)

White, Casey B; Fantone, Joseph C

2010-10-01

Traditionally, medical schools have tended to make assumptions that students will "automatically" engage in self-education effectively after graduation and subsequent training in residency and fellowships. In reality, the majority of medical graduates out in practice feel unprepared for learning on their own. Many medical schools are now adopting strategies and pedagogies to help students become self-regulating learners. Along with these changes in practices and pedagogy, many schools are eliminating a cornerstone of extrinsic motivation: discriminating grades. To study the effects of the switch from discriminating to pass-fail grading in the second year of medical school, we compared internal and external assessments and evaluations for a second-year class with a discriminating grading scale (Honors, High Pass, Pass, Fail) and for a second-year class with a pass-fail grading scale. Of the measures we compared (MCATs, GPAs, means on second-year examinations, USMLE Step 1 scores, residency placement, in which there were no statistically significant changes), the only statistically significant decreases (lower performance with pass fail) were found in two of the second-year courses. Performance in one other course also improved significantly. Pass-fail grading can meet several important intended outcomes, including "leveling the playing field" for incoming students with different academic backgrounds, reducing competition and fostering collaboration among members of a class, more time for extracurricular interests and personal activities. Pass-fail grading also reduces competition and supports collaboration, and fosters intrinsic motivation, which is key to self-regulated, lifelong learning.

Building Bridges One Line at a Time

Science.gov (United States)

Grigsby, Cathy Murray

2012-01-01

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

Pass-through of exchange rates and tariffs in Greek-US tobacco trade

OpenAIRE

Rezitis, Anthony N.; Brown, A. Blake

1999-01-01

The paper examines the extent to which exchange rate and unit tariff changes are passed-through in US import prices of unmanufactured Greek oriental tobacco. The results indicate partial pass-through of exchange rates and tariffs. Exchange rate pass-through is about 0.272 and tariff pass-through about 0.185. One possible reason for the partial pass-through is oligopoly in tobacco exporting. Oligopoly would imply that depreciation of the drachma relative to the US dollar benefits tobacco expor...

SURVEY RESULTS AND TESTING OF RAILWAY BRIDGES

Directory of Open Access Journals (Sweden)

I. H. Haniiev

2010-03-01

Full Text Available The article is devoted to the survey and testing of railway bridges by the State Joint-Stock Railway Company «Uzbekiston Temir Yollari» («Uzbekistan Railways». It is stated that in the existing rules on determination of the capacity of bridges the recommendations on taking into account the cumulative deflection to the moment of technical diagnostics of spans on the bridge capacity are absent. The author states on the need to develop a method for determining the wear of spans on restriction of the residual deflection in the bridge floor slabs.

23 CFR 650.705 - Application for discretionary bridge funds.

Science.gov (United States)

2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Application for discretionary bridge funds. 650.705... TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Discretionary Bridge Candidate Rating Factor § 650.705 Application for discretionary bridge funds. Each year through its field offices, the FHWA will...

New conceptual design of portable bamboo bridge for emergency purposes

Science.gov (United States)

Musthaffa, A. A.; Nor, N. M.; Yusof, M. A.; Yuhazri, M. Y.

2018-02-01

Portable bridges serve as routes for troops during the military operations and the disaster relief operation. Nowadays, bamboo has been regarded as one of the alternative construction materials for building and bridge structures. This paper presents the conceptual design of the portable bridge. Several types of portable bridges and bamboo bridges are reviewed in the current work. The characteristics, capability and method of construction of each bridge are discussed. Finally, the conceptual of the portable bamboo bridge for emergency purposes is presented. The idea of producing portable bridge is proposed in the current work as it is crucial for providing route for communities affected by natural disasters.

Realisation of low-voltage square-root-domain all-pass filters

Directory of Open Access Journals (Sweden)

Farooq A. Khanday

2013-10-01

Full Text Available Novel l ow-voltage first-order and second-order square-root-domain all-pass filters derived systematically by means of transfer function decomposition and state -space synthesis techniques are proposed. The employment of only a few geometric-mean cells and grounded capacitors permits the circuits to absorb shunt parasitic capacitances, which is desirable for production in monolithic form . The circuits enjoy the features of electronic adjustment of frequency characteristics, wider dynamic range and low-voltage environment operation. The filters are employed to design high-order all-pass filters using cascade approach. First-order low-pass and second-order band-pass filters, being the inherited building blocks of the proposed low-order all-pass filters are also discussed. The behaviour of the filters is evaluated through simulations using Taiwan semiconductor manufacturing company 0.25 μm level-3 complementary metal oxide semiconductor process parameters, where the most important performance factors are considered.

A cloud-based information repository for bridge monitoring applications

Science.gov (United States)

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

2016-04-01

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

Exchange rate pass-through in Switzerland: Evidence from vector autoregressions

OpenAIRE

Jonas Stulz

2007-01-01

This study investigates the pass-through of exchange rate and import price shocks to different aggregated prices in Switzerland. The baseline analysis is carried out with recursively identified vector autoregressive (VAR) models. The data set comprises monthly observations, and pass-through effects are quantified by means of impulse response functions. Evidence shows that the exchange rate pass-through to import prices is substantial (although incomplete), but only moderate to total consumer ...

Exchange rate pass-through and the role of international distribution channels

OpenAIRE

Desiraju, Ramarao; Shrikhande, Milind

1996-01-01

Manufacturers selling in foreign markets often do not completely pass on the effects of fluctuations in exchange rates to the prices of their products. Our paper addresses this puzzle and studies the effects of the international distribution channel on exchange rate pass-through. We develop an exchange rate pass-through model that takes into account the role of an intermediary between a domestic manufacturer and its consumers in a foreign market. We find that the magnitude of the pass-through...

The I-35W bridge Project Website

DEFF Research Database (Denmark)

Kampf, Constance

How can websites be used to rebuild trust?  In August 2007, the Interstate Highway 35-W bridge in Minneapolis, MN collapsed during rush hour.  Although many people were rescued and casualties were as limited as could be expected due to quick and effective intervention, the image of a major bridge...... collapsing during rush hour damaged the Minnesota Department of Transportation's reputation and resulted in the loss of public trust for the organization.  The ensuing bridge reconstruction project included a project website intended to rebuild this trust through transparency, community involvement......, and the use of multimodal features.  This paper looks at the I35-W bridge reconstruction project in Minneapolis through web-based communication by the Minnesota Department of Transportation (MnDOT) about the project. The MnDOT bridge reconstruction website will be examined using a combination of 1). Weick...

Investigation on the performance of bridge approach slab

Directory of Open Access Journals (Sweden)

Abdelrahman Amr

2018-01-01

Full Text Available In Egypt, where highway bridges are to be constructed on soft cohesive soils, the bridge abutments are usually founded on rigid piles, whereas the earth embankments for the bridge approaches are directly founded on the natural soft ground. Consequently, excessive differential settlement frequently occurs between the bridge deck and the bridge approaches resulting in a “bump” at both ends of the bridge deck. Such a bump not only creates a rough and uncomfortable ride but also represents a hazardous condition to traffic. One effective technique to cope with the bump problem is to use a reinforced concrete approach slab to provide a smooth grade transition between the bridge deck and the approach pavement. Investigating the geotechnical and structural performance of approach slabs and revealing the fundamental affecting factors have become mandatory. In this paper, a 2-D finite element model is employed to investigate the performance of approach slabs. Moreover, an extensive parametric study is carried out to appraise the relatively optimum geometries of approach slab, i.e. slab length, thickness, embedded depth and slope, that can yield permissible bumps. Different geo-mechanical conditions of the cohesive foundation soil and the fill material of the bridge embankment are examined.

History of cable-stayed bridges

DEFF Research Database (Denmark)

Gimsing, Niels Jørgen

1999-01-01

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

A Hierarchical Analysis of Bridge Decision Makers ... The Role of New Technology Adoption in the Timber Bridge Market: Special Project

Science.gov (United States)

Robert L. Smith; Robert J. Bush; Daniel L. Schmoldt

1995-01-01

Bridge design engineers and local highway officials make bridge replacement decisions across the United States. The Analytical Hierarchy Process was used to characterize the bridge material selection decision of these individuals. State Department of Transportation engineers, private consulting engineers, and local highway officials were personally interviewed in...

Intercellular bridges in vertebrate gastrulation.

Directory of Open Access Journals (Sweden)

Luca Caneparo

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

Setting Pass Scores for Clinical Skills Assessment

Directory of Open Access Journals (Sweden)

Min Liu

2008-12-01

Full Text Available In a clinical skills assessment, the decision to pass or fail an examinee should be based on the test content or on the examinees' performance. The process of deciding a pass score is known as setting a standard of the examination. This requires a properly selected panel of expert judges and a suitable standard setting method, which best fits the purpose of the examination. Six standard setting methods that are often used in clinical skills assessment are described to provide an overview of the standard setting process.

Single beam pass migmacell method and apparatus

International Nuclear Information System (INIS)

Maglich, B.C.; Nering, J.E.; Mazarakis, M.G.; Miller, R.A.

1976-01-01

The invention provides improvements in migmacell apparatus and method by dispensing with the need for metastable confinement of injected molecular ions for multiple precession periods. Injected molecular ions undergo a 'single pass' through the reaction volume. By preconditioning the injected beam such that it contains a population distribution of molecules in higher vibrational states than in the case of a normal distribution, injected molecules in the single pass exper-ience collisionless dissociation in the migmacell under magnetic influence, i.e., so-called Lorentz dissociation. Dissociationions then form atomic migma

Characterization of bridge foundations workshop report.

Science.gov (United States)

2013-11-01

"In 2013, the Federal Highway Administration proposed a new research program for the characterization of bridge foundations. To narrow the focus and develop a research roadmap for the program, a workshop on Characterization of Bridge Foundations...

Security analysis and improvements to the PsychoPass method.

Science.gov (United States)

Brumen, Bostjan; Heričko, Marjan; Rozman, Ivan; Hölbl, Marko

2013-08-13

In a recent paper, Pietro Cipresso et al proposed the PsychoPass method, a simple way to create strong passwords that are easy to remember. However, the method has some security issues that need to be addressed. To perform a security analysis on the PsychoPass method and outline the limitations of and possible improvements to the method. We used the brute force analysis and dictionary attack analysis of the PsychoPass method to outline its weaknesses. The first issue with the Psychopass method is that it requires the password reproduction on the same keyboard layout as was used to generate the password. The second issue is a security weakness: although the produced password is 24 characters long, the password is still weak. We elaborate on the weakness and propose a solution that produces strong passwords. The proposed version first requires the use of the SHIFT and ALT-GR keys in combination with other keys, and second, the keys need to be 1-2 distances apart. The proposed improved PsychoPass method yields passwords that can be broken only in hundreds of years based on current computing powers. The proposed PsychoPass method requires 10 keys, as opposed to 20 keys in the original method, for comparable password strength.

Validation of the one pass measure for motivational interviewing competence.

Science.gov (United States)

McMaster, Fiona; Resnicow, Ken

2015-04-01

This paper examines the psychometric properties of the OnePass coding system: a new, user-friendly tool for evaluating practitioner competence in motivational interviewing (MI). We provide data on reliability and validity with the current gold-standard: Motivational Interviewing Treatment Integrity tool (MITI). We compared scores from 27 videotaped MI sessions performed by student counselors trained in MI and simulated patients using both OnePass and MITI, with three different raters for each tool. Reliability was estimated using intra-class coefficients (ICCs), and validity was assessed using Pearson's r. OnePass had high levels of inter-rater reliability with 19/23 items found from substantial to almost perfect agreement. Taking the pair of scores with the highest inter-rater reliability on the MITI, the concurrent validity between the two measures ranged from moderate to high. Validity was highest for evocation, autonomy, direction and empathy. OnePass appears to have good inter-rater reliability while capturing similar dimensions of MI as the MITI. Despite the moderate concurrent validity with the MITI, the OnePass shows promise in evaluating both traditional and novel interpretations of MI. OnePass may be a useful tool for developing and improving practitioner competence in MI where access to MITI coders is limited. Copyright © 2015. Published by Elsevier Ireland Ltd.

An efficient CMOS bridging fault simulator with SPICE accuracy

NARCIS (Netherlands)

Di, C.; Jess, J.A.G.

1996-01-01

This paper presents an alternative modeling and simulation method for CMOS bridging faults. The significance of the method is the introduction of a set of generic-bridge tables which characterize the bridged outputs for each bridge and a set of generic-cell tables which characterize how each cell

33 CFR 118.110 - Daymarks and lateral lighting on bridges.

Science.gov (United States)

2010-07-01

... bridges. 118.110 Section 118.110 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LIGHTING AND OTHER SIGNALS § 118.110 Daymarks and lateral lighting on bridges. (a... through bridges with U.S. aids to navigation system lateral marks and lights installed on the...

Some aspects of technical models within bridge management system

Directory of Open Access Journals (Sweden)

Grković Slobodan

2015-01-01

Full Text Available Bridge Management System (BMS represents a rational and systematic approach to organizing and conducting of all activities related to bridge maintenance. Main goal of BMS is helping the bridge owner to make an optimal decision with respect to bridge maintenance budget, whether it is dedicated to one bridge or to group of bridges, by securing that the decision is made on the basis of Life-Cycle Cost (LCC estimates. The structure of BMS is based on condition rating and Bridge Database (BD, Deterioration model (DM, Cost Model for evaluation of costs and Optimization Model for choosing the most rational maintenance strategy. Relationship between bridge condition rating and DM with maintenance costs within BMS is very important. Predictions regarding future intensity and rate of bridge deterioration depends on multitude of factors and it is a consequence of several simultaneous actions and deterioration processes (DP which need to be included into DMs. DMs are mostly based on modeling of physical and chemical actions and processes or they are based on statistical analysis of large number of data regarding the condition of existing bridges, or on artificial intelligence models, etc. Stochastic models based on Markov processes are applied within more advanced contemporary BMS. Due to social and economic circumstances and lack of financial resources over the last two decades in Republic of Serbia bridge maintenance was neglected and creation of BD was discontinued. The paper deliberates some aspects of technical models within BMS, with DMs being pointed out, development of BD within bridge maintenance in Republic of Serbia and it gives an overview of sophisticated BMS and current advances in this field.

Monitoring system of arch bridge for safety network management

Science.gov (United States)

Joo, Bong Chul; Yoo, Young Jun; Lee, Chin Hyung; Park, Ki Tae; Hwang, Yoon Koog

2010-03-01

Korea has constructed the safety management network monitoring test systems for the civil infrastructure since 2006 which includes airport structure, irrigation structure, railroad structure, road structure, and underground structure. Bridges among the road structure include the various superstructure types which are Steel box girder bridge, suspension bridge, PSC-box-girder bridge, and arch bridge. This paper shows the process of constructing the real-time monitoring system for the arch bridge and the measured result by the system. The arch type among various superstructure types has not only the structural efficiency but the visual beauty, because the arch type superstructure makes full use of the feature of curve. The main measuring points of arch bridges composited by curved members make a difference to compare with the system of girder bridges composited by straight members. This paper also shows the method to construct the monitoring system that considers the characteristic of the arch bridge. The system now includes strain gauges and thermometers, and it will include various sensor types such as CCTV, accelerometers and so on additionally. For the long term and accuracy monitoring, the latest optical sensors and equipments are applied to the system.

A Comparison of Limb-Socket Kinematics of Bone-Bridging and Non-Bone-Bridging Wartime Transtibial Amputations

Science.gov (United States)

2012-05-16

each successive loading interval. Subset analysis was performed on the basis of amputation type (bone bridging or non bone bridging) and suspension...fitting, patient care. Washington, DC: US Government Printing Office; 1969. 2. Ertl J. Uber amputationsstumpfe. Chirurg. 1949;20:218 24. 3. Pinto MA

Time variation in European carbon pass-through rates in electricity futures prices

International Nuclear Information System (INIS)

Huisman, Ronald; Kiliç, Mehtap

2015-01-01

The European Union Emissions Trading Scheme is a means to price emission allowances. Electricity market prices should reflect these market prices of emission allowances as they are a cost factor for power producers. The pass-through rate is the fraction of the emission allowance price that is passed through to electricity market prices. It is often measured and presented as an average or a fixed estimate over some time period. However, we expect that the pass-through rates should actually vary over time as electricity supply curves reflect the marginal costs of different producers that differ in emission intensity. We apply a Kalman Filter approach to observe pass-through rates in Germany and U.K. and find strong support for time varying instead of fixed pass-through rates. Although policy makers are interested in the impact of a policy on average, our results indicate that one needs to be careful with the time-frame over which pass-through rates are measured for policy evaluation, as an incorrect chosen evaluation period could cause an under- or overestimation of the pass-through rate. In addition, our model helps to provide policy makers with insight in the development of pass-through rates when market circumstances change with respect to power production. - Highlights: • We analyse the time-variation of the emission pass-through rate in power prices. • We examine historical futures prices for Germany and the U.K. • We test the hypothesis by using the Kalman Filter methodology. • Strong support is found that pass-through rates vary over time. • The chosen time-frame for pass-through rates is important for policy evaluation.

Suspension Bridge Flutter for Girder with Separate Control Flaps

DEFF Research Database (Denmark)

Huynh, T.; Thoft-Christensen, Palle

Active vibration control of long span suspension bridge flutter using separated control flaps (SFSC) has shown to increase effectively the critical wind speed of bridges. In this paper, an SFSC calculation based on modal equations of the vertical and torsional motions of the bridge girder including...... the flaps is presented. The length of the flaps attached to the girder, the flap configuration and the flap rotational angles are parameters used to increase the critical wind speed of the bridge. To illustrate the theory a numerical example is shown for a suspension bridge of 1000m+2500m+1000m span based...... on the Great Belt Bridge streamlined girder....

Two high-frequency mutual inductance bridges with high resolution

NARCIS (Netherlands)

Flokstra, Jakob; Gerritsma, G.J.; Kreuwel, H.J.M.; van der Marel, L.C.

1980-01-01

Two mutual inductance bridges are described for operation up to about 100 kHz. Special attention is paid to the sensitivity and resolution of the bridges. Both bridges can be used to measure variations of about 10 pH in the mutual inductance. The first bridge consists of passive elements only

23 CFR 650.805 - Bridges not requiring a USCG permit.

Science.gov (United States)

2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Bridges not requiring a USCG permit. 650.805 Section 650... OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.805 Bridges not... permit is not required for bridge construction. This determination shall be made at an early stage of...

Using rotating liquid bridges as accelerometers

Energy Technology Data Exchange (ETDEWEB)

Montanero, J.M. [Universidad de Extremadura, Badajoz (Spain). Dept. de Electronica e Ingenieria Electromecanica; Cabezas, G.; Acero, J.; Zayas, F.

1999-07-01

Liquid bridges have recently been proposed as fluid accelerometers that could be used to measure very small inertial forces under microgravity conditions [Meseguer et al., microgravity sci. technol. IX/2 (1996)]. The essential idea is to infer the values of such inertial forces from the liquid bridge interface contour, whose shape obviously depends on the values of such forces (apart from the bridge volume and the geometry of the supporting disks). Following a similar procedure, in this paper we explore the use of rotating axisymmetric liquid bridges to measure the residual axial gravity and the rotation rate of the liquid bridge regarded as a solid body. In light off the difficulties involved in performing experiments on Earth, the role of empirical data is played by an accurate numerical solution of the Young-Laplace equation. The values of both the axial gravity and angular speed are obtained by fitting the approximate analytical expressions derived in this paper to the numerical solution of the Young-Laplace equation. The comparison between the predicted and actual values of the variables of interest shows a satisfactory agreement, supporting the suitability of the procedure. (orig.)

Advanced materials for control of post-earthquake damage in bridges

International Nuclear Information System (INIS)

Shrestha, Kshitij C; Saiidi, M Saiid; Cruz, Carlos A

2015-01-01

This paper presents analytical modeling to study the seismic response of bridge systems with conventional and advanced details. For validation, a 33 m quarter-scale model of a four-span bridge incorporating innovative materials and details seismically tested on the shake tables at the University of Nevada, Reno was taken. The bridge specimen involved use of advanced materials and details to reduce damage at plastic hinges and minimize residual displacements. A three-dimensional, nonlinear model incorporating the response of the innovative materials was developed to study the bridge response using the finite-element software OpenSees. Existing finite-element formulations were used to capture the response of the advanced materials used in the bridge. The analytical model was found to be able to reproduce comparable bent displacements and bent shear forces within reasonable accuracy. The validated model was further used to study different types of bridges under suite of scaled bi-directional near-fault ground motions. Comparisons were made on behavior of five different bridge types, first conventional reinforced concrete bridge, second post-tensioned column bridge, third bridge with elastomeric rubber elements at the plastic hinge zone, fourth bridge with nickel–titanium superelastic shape memory alloy (SMA) reinforcing bar and fifth bridge with CuAlMn superelastic SMA reinforcing bar. Both the SMA used bridges also utilized engineered cementitious composite element at the plastic hinge zone. The results showed effectiveness of the innovative interventions on the bridges in providing excellent recentering capabilities with minimal damage to the columns. (paper)

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......, Brian O’Neill, Andra Siibak, Sascha Trültzsch-Wijnen, Nicoletta Vittadini, Igor Vobič and Frauke Zeller. Stakeholder feedback from: Michelle Arlotta (DeAgostini), Andreea M. Costache (Association of Consumers of Audiovisual Media in Catalonia/TAC), Francesco Diasio (AMARC Europe), Marius Dragomir (Open...

Mathematical bridges

CERN Document Server

Andreescu, Titu; Tetiva, Marian

2017-01-01

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

Free energy landscape of a minimalist salt bridge model.

Science.gov (United States)

Li, Xubin; Lv, Chao; Corbett, Karen M; Zheng, Lianqing; Wu, Dongsheng; Yang, Wei

2016-01-01

Salt bridges are essential to protein stability and dynamics. Despite the importance, there has been scarce of detailed discussion on how salt bridge partners interact with each other in distinct solvent exposed environments. In this study, employing a recent generalized orthogonal space tempering (gOST) method, we enabled efficient molecular dynamics simulation of repetitive breaking and reforming of salt bridge structures within a minimalist salt-bridge model, the Asp-Arg dipeptide and thereby were able to map its detailed free energy landscape in aqueous solution. Free energy surface analysis shows that although individually-solvated states are more favorable, salt-bridge states still occupy a noticeable portion of the overall population. Notably, the competing forces, e.g. intercharge attractions that drive the formation of salt bridges and solvation forces that pull the charged groups away from each other, are energetically comparable. As the result, the salt bridge stability is highly tunable by local environments; for instance when local water molecules are perturbed to interact more strongly with each other, the population of the salt-bridge states is likely to increase. Our results reveal the critical role of local solvent structures in modulating salt-bridge partner interactions and imply the importance of water fluctuations on conformational dynamics that involves solvent accessible salt bridge formations. © 2015 The Protein Society.

Contact conditions in skin-pass rolling

DEFF Research Database (Denmark)

Kijima, Hideo; Bay, Niels

2007-01-01

The special contact conditions in skin-pass rolling of steel strip is analysed by studying plane strain upsetting of thin sheet with low reduction applying long narrow tools and dry friction conditions. An extended sticking region is estimated by an elasto-plastic FEM analysis of the plane strain...... upsetting. This sticking region causes a highly inhomogeneous elasto-plastic deformation with large influence of work-hardening and friction. A numerical analysis of skin-pass rolling shows the same contact conditions, i.e. an extended sticking region around the center of the contact zone. The calculated...... size of the sticking region with varying contact length and pressure/reduction is experimentally verified by plane strain upsetting tests measuring the local surface deformation of the work pieces after unloading....

Upaya Meningkatkan Kemampuan Passing Bawah Bola Voli Pada

OpenAIRE

Irawan, Dedi

2017-01-01

This research uses research "Classroom Action Research" (Classroom Action Research) with variables: Improved Passing Down volleyball through media modified rubber ball. Subjects in this study were fifth grade students of State Elementary School 23 Palus Hulu subdistrict Belimbing Melawi totaling 28 students. This research technique using test and measurement, a test with a grating instrument measuring learning outcomes passing down the volleyball game. Analysis of data using percentages. Thes...

Port Needs Study (Vessel Traffic Services Benefits). Volume 2: Appendices, Part 1

Science.gov (United States)

1991-08-01

34 (Reference 1) and with its companion , Point Arguello, has been the graveyard of many ships. The Point Conception area has been described as a transition...North entrance to the Inner Harbor Navigation Canal, and that portion of the ICW Rigolets-New Orleans Cut west of a point one mile east of Chef

A COMPARATIVE STUDY RELATING PASS BETWEEN MALE AND FEMALE BASKETBALL PLAYERS

Directory of Open Access Journals (Sweden)

Antonios THEOHAROPOULOS

2010-04-01

Full Text Available The main goal of this research is to examine the importance of different kind of passes through their frequency of appearance and success that male and female basketball players execute in Greek championships.The sample consisted of male and female teams of Thessaloniki - Greece. The 1st group consisted of male teams (18 from different divisions while the 2nd group consisted of female teams (10. Data collection was based on personal observation by a research team, who registries the kind of passes that took place either from the sampleteam or the opposite teams. The passes that were registered are: behind the back, chest, overhead, push, hand with hand, bounce and baseball pass. The analysis of variance (Anova in types of passes was formed, based on the factor “sex” (male-female. Specifically the comparisons were made between: a the total number of eachpass b their successful number c their frequency of appearance d and their total successful percentage. The results indicate that statistically significant differences exist between the two sexes, concerning the total number, the successful number and the percentages of success for the most used passes in Greek basketball. The analysis indicates that male and female basketball players tend to use different kind of passes during activity.

9 CFR 310.6 - Carcasses and parts passed for cooking; marking.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Carcasses and parts passed for cooking... INSPECTION AND CERTIFICATION POST-MORTEM INSPECTION § 310.6 Carcasses and parts passed for cooking; marking. Carcasses and parts passed for cooking shall be marked conspicuously on the surface tissues thereof by a...

Statistical variability and confidence intervals for planar dose QA pass rates

Energy Technology Data Exchange (ETDEWEB)

Bailey, Daniel W.; Nelms, Benjamin E.; Attwood, Kristopher; Kumaraswamy, Lalith; Podgorsak, Matthew B. [Department of Physics, State University of New York at Buffalo, Buffalo, New York 14260 (United States) and Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Canis Lupus LLC, Merrimac, Wisconsin 53561 (United States); Department of Biostatistics, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States); Department of Molecular and Cellular Biophysics and Biochemistry, Roswell Park Cancer Institute, Buffalo, New York 14263 (United States) and Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, New York 14214 (United States)

2011-11-15

Purpose: The most common metric for comparing measured to calculated dose, such as for pretreatment quality assurance of intensity-modulated photon fields, is a pass rate (%) generated using percent difference (%Diff), distance-to-agreement (DTA), or some combination of the two (e.g., gamma evaluation). For many dosimeters, the grid of analyzed points corresponds to an array with a low areal density of point detectors. In these cases, the pass rates for any given comparison criteria are not absolute but exhibit statistical variability that is a function, in part, on the detector sampling geometry. In this work, the authors analyze the statistics of various methods commonly used to calculate pass rates and propose methods for establishing confidence intervals for pass rates obtained with low-density arrays. Methods: Dose planes were acquired for 25 prostate and 79 head and neck intensity-modulated fields via diode array and electronic portal imaging device (EPID), and matching calculated dose planes were created via a commercial treatment planning system. Pass rates for each dose plane pair (both centered to the beam central axis) were calculated with several common comparison methods: %Diff/DTA composite analysis and gamma evaluation, using absolute dose comparison with both local and global normalization. Specialized software was designed to selectively sample the measured EPID response (very high data density) down to discrete points to simulate low-density measurements. The software was used to realign the simulated detector grid at many simulated positions with respect to the beam central axis, thereby altering the low-density sampled grid. Simulations were repeated with 100 positional iterations using a 1 detector/cm{sup 2} uniform grid, a 2 detector/cm{sup 2} uniform grid, and similar random detector grids. For each simulation, %/DTA composite pass rates were calculated with various %Diff/DTA criteria and for both local and global %Diff normalization

STUDY OF BRIDGE DECK A REVIEW

OpenAIRE

MISS. KSHITIJA S. BALWAN , MR. V. G. KHURD , MR. S. S. CHOUGULE

2018-01-01

The objective of this study was to understand the meaning of bridge deck. To know the different forms of decks used in bridge design. To understand different methods used for analysis of deck and study of box girder and its evolution

Strategic Planning for the National Bridge Stock of Iran

Directory of Open Access Journals (Sweden)

Ali Sahrapeyma

2013-06-01

Full Text Available The National Bridge Stock of Iran consists of about 330,000 bridges, of which around 50% are older than 30 years. Since 2010, Iran Road Maintenance & Transportation Organization has started implementing a comprehensive Bridge Management System in order to manage this aged stock efficiently. To predict future conditions of bridge stock, a heuristic numerical method is presented. This methodology is based on Markovian process to model deterioration of bridge decks and a multi-objective optimization problem to find the best solutions. The optimization problem involves three decision variables regarding management strategies, and has three objectives regarding cost minimization. Constraints of the problem are the percentage of deficient bridges, the percentage of bridges under MR&Rs (Maintenance, Repair and Rehabilitation and the average value of condition scores. The results show that to avoid future challenges, the annual budget for bridge maintenance should be increased, the current maintenance strategy should be improved as soon as possible, and national manuals and instructions for inspection, condition rating and maintenance should be developed.

Foot force models of crowd dynamics on a wobbly bridge.

Science.gov (United States)

Belykh, Igor; Jeter, Russell; Belykh, Vladimir

2017-11-01

Modern pedestrian and suspension bridges are designed using industry standard packages, yet disastrous resonant vibrations are observed, necessitating multimillion dollar repairs. Recent examples include pedestrian-induced vibrations during the opening of the Solférino Bridge in Paris in 1999 and the increased bouncing of the Squibb Park Bridge in Brooklyn in 2014. The most prominent example of an unstable lively bridge is the London Millennium Bridge, which started wobbling as a result of pedestrian-bridge interactions. Pedestrian phase locking due to footstep phase adjustment is suspected to be the main cause of its large lateral vibrations; however, its role in the initiation of wobbling was debated. We develop foot force models of pedestrians' response to bridge motion and detailed, yet analytically tractable, models of crowd phase locking. We use biomechanically inspired models of crowd lateral movement to investigate to what degree pedestrian synchrony must be present for a bridge to wobble significantly and what is a critical crowd size. Our results can be used as a safety guideline for designing pedestrian bridges or limiting the maximum occupancy of an existing bridge. The pedestrian models can be used as "crash test dummies" when numerically probing a specific bridge design. This is particularly important because the U.S. code for designing pedestrian bridges does not contain explicit guidelines that account for the collective pedestrian behavior.

Hierarchical analysis of bridge decision makers : the role of new technology adoption in the timber bridge market : special project fiscal year 1992

Science.gov (United States)

1995-08-01

Bridge design engineers and local highway officials make bridge replacement decisions across the : United States. The Analytical Hierarchy Process was used to characterize the bridge material selection : decision of these individuals. State Departmen...

Application of bridging-law concepts to short-fibre composites

DEFF Research Database (Denmark)

Lindhagen, J.E.; Gamstedt, Kristofer; Berglund, L.A.

2000-01-01

This is the third paper in a series of four where notch sensitivity, fracture energy and bridging laws are studied in short-fibre polymer composites. Here, bridging laws are derived from experimental crack-opening profiles in centre-hole notched tensile specimens. The materials studied are three...... types of commercial glass-mat composites with different reinforcement structures and matrices. The materials have softening bridging laws and the calculated fracture energies from bridging laws are in good agreement with values determined directly by experiment. The calculated maximum local bridging...

GaggleBridge: collaborative data analysis.

Science.gov (United States)

Battke, Florian; Symons, Stephan; Herbig, Alexander; Nieselt, Kay

2011-09-15

Tools aiding in collaborative data analysis are becoming ever more important as researchers work together over long distances. We present an extension to the Gaggle framework, which has been widely adopted as a tool to enable data exchange between different analysis programs on one computer. Our program, GaggleBridge, transparently extends this functionality to allow data exchange between Gaggle users at different geographic locations using network communication. GaggleBridge can automatically set up SSH tunnels to traverse firewalls while adding some security features to the Gaggle communication. GaggleBridge is available as open-source software implemented in the Java language at http://it.inf.uni-tuebingen.de/gb. florian.battke@uni-tuebingen.de Supplementary data are available at Bioinformatics online.

Seismic Performance of Multi-Span RC Railway Bridges

DEFF Research Database (Denmark)

Georgakis, Christos; Barrau, Xavier

2008-01-01

Presently, there is no clear method for determining the optimal railway bridge design for a particular ground type and expected seismic intensity. Four main types of RC bridge dominate the current multi-span railway bridge design trends – the Simply Supported Beam, Continuous Box-Girder (CBG), CBG...

Durability of Materials in Pearl-Chain Bridges

DEFF Research Database (Denmark)

Lund, Mia Schou Møller

. The construction of the Pearl-Chain arch is simple. The arch is assembled on its side, next to the road that the bridge will span, by placing a number of plane prefabricated Super-Light Decks that consist of lightweight aggregate concrete and conventional concrete, in the desired arch shape. Mortar joints are cast...... is stabilized by casting a fill material between the spandrel walls of the arch. Finally, the road surface is cast on top of the fill material. New bridges are designed for a service lifetime of at least 100 years. Hence, the specifications of the materials used in Pearl-Chain Bridges are high. This PhD study...... and pervious concrete were also investigated. The most suitable fill material for Pearl-Chain Bridges depends on the particular bridge design; the results obtained and presented in the present PhD study provide guidance on how to decide which fill material is most suitable regarding strength, permeability...

A prototype for the PASS Permanent All Sky Survey

Science.gov (United States)

Deeg, H. J.; Alonso, R.; Belmonte, J. A.; Horne, K.; Alsubai, K.; Collier Cameron, A.; Doyle, L. R.

2004-10-01

A prototype system for the Permanent All Sky Survey (PASS) project is presented. PASS is a continuous photometric survey of the entire celestial sphere with a high temporal resolution. Its major objectives are the detection of all giant-planet transits (with periods up to some weeks) across stars up to mag 10.5, and to deliver continuously photometry that is useful for the study of any variable stars. The prototype is based on CCD cameras with short focal length optics on a fixed mount. A small dome to house it at Teide Observatory, Tenerife, is currently being constructed. A placement at the antarctic Dome C is also being considered. The prototype will be used for a feasibility study of PASS, to define the best observing strategies, and to perform a detailed characterization of the capabilities and scope of the survey. Afterwards, a first partial sky surveying will be started with it. That first survey may be able to detect transiting planets during its first few hundred hours of operation. It will also deliver a data set around which software modules dealing with the various scientific objectives of PASS will be developed. The PASS project is still in its early phase and teams interested in specific scientific objectives, in providing technical expertise, or in participating with own observations are invited to collaborate.

Chapter 10:Hardwoods for timber bridges

Science.gov (United States)

James P. Wacker; Ed T. Cesa

2005-01-01

This chapter describes the joint efforts of the Forest Service and the FHWA to administer national programs including research, demonstration bridges, and technology transfer components. Summary information on a number of Forest Service-WIT demonstration bridges constructed with hardwoods is also provided.

Identifying hidden sexual bridging communities in Chicago.

Science.gov (United States)

Youm, Yoosik; Mackesy-Amiti, Mary Ellen; Williams, Chyvette T; Ouellet, Lawrence J

2009-07-01

Bridge populations can play a central role in the spread of human immunodeficiency virus (HIV) by providing transmission links between higher and lower prevalence populations. While social network methods are well suited to the study of bridge populations, analyses tend to focus on dyads (i.e., risk between drug and/or sex partners) and ignore bridges between distinct subpopulations. This study takes initial steps toward moving the analysis of sexual network linkages beyond individual and risk group levels to a community level in which Chicago's 77 community areas are examined as subpopulations for the purpose of identifying potential bridging communities. Of particular interest are "hidden" bridging communities; that is, areas with above-average levels of sexual ties with other areas but whose below-average AIDS prevalence may hide their potential importance for HIV prevention. Data for this analysis came from the first wave of recruiting at the Chicago Sexual Acquisition and Transmission of HIV Cooperative Agreement Program site. Between August 2005 through October 2006, respondent-driven sampling was used to recruit users of heroin, cocaine, or methamphetamine, men who have sex with men regardless of drug use, the sex partners of these two groups, and sex partners of the sex partners. In this cross-sectional study of the sexual transmission of HIV, participants completed a network-focused computer-assisted self-administered interview, which included questions about the geographic locations of sexual contacts with up to six recent partners. Bridging scores for each area were determined using a matrix representing Chicago's 77 community areas and were assessed using two measures: non-redundant ties and flow betweenness. Bridging measures and acquired immunodeficiency syndrome (AIDS) case prevalence rates were plotted for each community area on charts representing four conditions: below-average bridging and AIDS prevalence, below-average bridging and above

Terrorismihirm sunnib muretsema kalleid mikrokiibiga passe / Andrus Karnau

Index Scriptorium Estoniae

Karnau, Andrus

2005-01-01

Alates 1. septembrist 2006 peavad kõik EL-i liikmesriigid hakkama väljastama mikrokiibiga varustatud passe, mille hinnaks võib kujuneda kuni 1000 krooni ja kehtivus lüheneb viiele aastale. Mikrokiip sisaldab inimese biomeetrilisi andmeid - esialgu vaid näokujutist, alates 2008. aastast näpujälgi ning hiljem ka andmeid silmaiirise ja juuksevärvi kohta. Lisa: Biomeetriline pass peidab intiimseid isikuandmeid. Kommenteerib Kohtuekspertiisi ja Kriminalistika Keskuse infojuht Aivar Pau

Aesthetic coatings for concrete bridge components

Science.gov (United States)

Kriha, Brent R.

This thesis evaluated the durability and aesthetic performance of coating systems for utilization in concrete bridge applications. The principle objectives of this thesis were: 1) Identify aesthetic coating systems appropriate for concrete bridge applications; 2) Evaluate the performance of the selected systems through a laboratory testing regimen; 3) Develop guidelines for coating selection, surface preparation, and application. A series of site visits to various bridges throughout the State of Wisconsin provided insight into the performance of common coating systems and allowed problematic structural details to be identified. To aid in the selection of appropriate coating systems, questionnaires were distributed to coating manufacturers, bridge contractors, and various DOT offices to identify high performing coating systems and best practices for surface preparation and application. These efforts supplemented a literature review investigating recent publications related to formulation, selection, surface preparation, application, and performance evaluation of coating materials.

1,2-bridged quadricyclanes

International Nuclear Information System (INIS)

Hart, H.; Cheng-Tai Peng

1982-01-01

The readily available benzodihydropentalene 6 and dimethyl acetylenedicarboxylate react to give norbornadiene diester 8, with a three-carbon bridge from C 1 to C 2 . Irradiation of 8 gives the corresponding C 1 -C 2 bridged quadricyclane diester 9, a new ring system. Diester 9 is quite stable, reverting to 8 with a tsub(1/2) of 30 min at 170 0 C. The corresponding diacid 11, also prepared, reverts to its norbornadiene precursor at a considerably lower temperature, possibly as a consequence of acid catalysis. (author)

Influence of Icing on Bridge Cable Aerodynamics

DEFF Research Database (Denmark)

Koss, Holger; Frej Henningsen, Jesper; Olsen, Idar

2013-01-01

In recent years the relevance of ice accretion for wind-induced vibration of structural bridge cables has been recognised and became a subject of research in bridge engineering. Full-scale monitoring and observation indicate that light precipitation at moderate low temperatures between zero and -5......°C may lead to large amplitude vibrations of bridge cables under wind action. For the prediction of aerodynamic instability quasi-steady models have been developed estimating the cable response magnitude based on structural properties and aerodynamic force coefficients for drag, lift and torsion...... forces of different bridge cables types. The experiments were conducted in a wind tunnel facility capable amongst others to simulate incloud icing conditions....

Ambient Response Analysis of the Great Belt Bridge

DEFF Research Database (Denmark)

Brincker, Rune; Frandsen, Jeanette B.; Andersen, Palle

2000-01-01

In this paper an ambient response analysis of the Great Belt Bridge is presented. The Great Belt Bridge is one of the largest suspension bridges in the world, and the analysis was carried out in order to investigate the possibilities of estimating reliable damping values from the ambient response...

Ways of ensuring the standard of bridge superstructures.

OpenAIRE

M.G. Malgin; V.I. Kiryan

2011-01-01

The structural features of welded railway bridges of the last century were considered. The basic causes of appearance of fatigue cracks in welded joints of railway bridges were assessed. Structural and technological ways of provision of the design life of operated and new-built welded railway bridges are discussed.

OnWien Bridge Oscillators as Modified Multi-vibrators

DEFF Research Database (Denmark)

Lindberg, Erik

2014-01-01

A tutorial introduction to electrical oscilla- tors. Investigating Wien bridge oscillators as modified multi-vibrators. Introducing chaotic behavior into a Wien bridge oscillator by means of adding a simple nonlinear cir- cuit as a load of one of the amplifier input terminals......A tutorial introduction to electrical oscilla- tors. Investigating Wien bridge oscillators as modified multi-vibrators. Introducing chaotic behavior into a Wien bridge oscillator by means of adding a simple nonlinear cir- cuit as a load of one of the amplifier input terminals...

Bridge monitoring by interferometric deformation sensors

Science.gov (United States)

Inaudi, Daniele; Vurpillot, Samuel; Casanova, Nicoletta

1996-09-01

In many concrete bridges, the deformations are the most relevant parameter to be monitored in both short and long- terms. Strain monitoring gives only local information about the material behavior and too many such sensors would therefore be necessary to gain a complete understanding of the bridge behavior. We have found that fiber optic deformation sensors, with measurement bases of the order of one to a few meters, can give useful information both during the first days after concrete pouring and in the long term. In a first phase it is possible to monitor the thermal expansion due to the exothermic setting reaction and successively the thermal and drying shrinkages. Thanks to the long sensor basis, the detection of a crack traverse to the measurement region becomes probable and the evolution of cracks can therefore be followed with a reduced number of sensors. In the long-term it is possible to measure the geometric deformations and therefore the creeping of the bridge under static loads, especially under its own weight. In the past two years, our laboratory has installed hundreds of fiber optic deformation sensors in more than five concrete, composite steel-concrete, refurbished and enlarged bridges (road, highway and railway bridges). The measuring technique relies on low-coherence interferometry and offers a resolution down to a few microns even for long-term measurements. This contribution briefly discusses the measurement technique and then focuses on the development of a reliable sensor for direct concrete embedding and on the experimental results obtained on these bridges.

Guanidinium-Induced Denaturation by Breaking of Salt Bridges.

Science.gov (United States)

Meuzelaar, Heleen; Panman, Matthijs R; Woutersen, Sander

2015-12-07

Despite its wide use as a denaturant, the mechanism by which guanidinium (Gdm(+) ) induces protein unfolding remains largely unclear. Herein, we show evidence that Gdm(+) can induce denaturation by disrupting salt bridges that stabilize the folded conformation. We study the Gdm(+) -induced denaturation of a series of peptides containing Arg/Glu and Lys/Glu salt bridges that either stabilize or destabilize the folded conformation. The peptides containing stabilizing salt bridges are found to be denatured much more efficiently by Gdm(+) than the peptides containing destabilizing salt bridges. Complementary 2D-infrared measurements suggest a denaturation mechanism in which Gdm(+) binds to side-chain carboxylate groups involved in salt bridges. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Measurements of bridges' vibration characteristics using a mobile phone

Directory of Open Access Journals (Sweden)

Z. M. C. Pravia

Full Text Available ABSTRACTThis research presents an alternative way to perform a bridge inspection, which considers the dynamics parameters from the structure. It shows an experimental phase with use of a mobile phone to extract the accelerations answers from two concrete bridges, from those records is feasible to obtain natural frequencies using the Fast Fourier Transform (FFT.Numerical models with uses finite element model (FEM allow to determine the natural frequencies from the two concrete bridges and compare with the experimental phase of each one. The final results shows it's possible to use mobiles phones to extract vibration answers from concrete bridges and define the structural behavior of bridges from natural frequencies, this procedure could be used to evaluate bridges with lower costs.

Gust loading on streamlined bridge decks

DEFF Research Database (Denmark)

Larose, Guy; Mann, Jakob

1998-01-01

The current analytical description of the buffeting action of wind on long-span bridges is based on the strip assumption. However, recent experiments on closed-box girder bridge decks have shown that this assumption is not valid and is the source of an important part of the error margin...... of the analytical prediction methods. In this paper, an analytical model that departs from the strip assumption is used to describe the gust loading on a thin airfoil. A parallel is drawn between the analytical model and direct measurements of gust loading on motionless closed-box girder bridge decks. Empirical...

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

9 CFR 381.79 - Passing of carcasses and parts.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Passing of carcasses and parts. 381.79 Section 381.79 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Carcasses and Parts § 381.79 Passing of carcasses and parts. Each carcass and all organs and other parts of...

Performance indicators for roadway bridges

OpenAIRE

Strauss, A.; Vidovic, A.; Zambon, I.; Dengg, F.; Tanasic, N.; Matos, José C.

2016-01-01

Publicado em "Maintenance, monitoring, safety, risk and resilience of bridges and bridge networks". ISBN 978-1-138-02851-7 The performance indicators should, by its definition, allow capturing the life-cycle degradation processes affecting maintenance plans or the remaining lifetime. The qualitative or quantitative performance indicators are obtained through visual inspections, non-destructive tests or monitoring systems. After their quantification and the comparison with the resp...

An Empirical Study of Exchange Rate Pass-Through in China

OpenAIRE

Xiaowen Jin

2012-01-01

This paper seeks to estimate exchange rate pass-through in China and investigate its relationship with monetary policy. Linear and VAR models are applied to analyze robustness. The linear model shows that, over the long run, a 1% appreciation of NEER causes a decline in the CPI inflation rate of 0.132% and PPI inflation rate of 0.495%. The VAR model supports the results of the linear model, suggesting a fairly low CPI pass-through and relatively higher PPI pass-through. Furthermore, thi...

Probabilistic and sensitivity analysis of Botlek Bridge structures

Directory of Open Access Journals (Sweden)

Králik Juraj

2017-01-01

Full Text Available This paper deals with the probabilistic and sensitivity analysis of the largest movable lift bridge of the world. The bridge system consists of six reinforced concrete pylons and two steel decks 4000 tons weight each connected through ropes with counterweights. The paper focuses the probabilistic and sensitivity analysis as the base of dynamic study in design process of the bridge. The results had a high importance for practical application and design of the bridge. The model and resistance uncertainties were taken into account in LHS simulation method.

Future-based Static Analysis of Message Passing Programs

Directory of Open Access Journals (Sweden)

Wytse Oortwijn

2016-06-01

Full Text Available Message passing is widely used in industry to develop programs consisting of several distributed communicating components. Developing functionally correct message passing software is very challenging due to the concurrent nature of message exchanges. Nonetheless, many safety-critical applications rely on the message passing paradigm, including air traffic control systems and emergency services, which makes proving their correctness crucial. We focus on the modular verification of MPI programs by statically verifying concrete Java code. We use separation logic to reason about local correctness and define abstractions of the communication protocol in the process algebra used by mCRL2. We call these abstractions futures as they predict how components will interact during program execution. We establish a provable link between futures and program code and analyse the abstract futures via model checking to prove global correctness. Finally, we verify a leader election protocol to demonstrate our approach.

Shaking Table Tests of Curved Bridge considering Bearing Friction Sliding Isolation

Directory of Open Access Journals (Sweden)

Lei Yan

2016-01-01

Full Text Available Specific to severe damage to curved bridges in earthquakes caused by the excessive force of the fixed bearings and piers, a new seismic design method on curved bridges considering bearing friction sliding isolation is proposed in this paper. Seismic model bridge and isolation model bridge with similarity ratio of 1/20 were made and the shaking table comparison test was conducted. The experimental results show that the isolation model curved bridge suffered less seismic damage than the seismic model curved bridge. The fundamental frequencies of the seismic model bridge and isolation model bridge decreased and the damping ratio increased with the increase of seismic intensity. Compared with seismic curved bridge, the maximum reduction rates of peak acceleration along the radial and tangential directions on the top of pier of the isolation model curved bridge were 47.3% and 55.5%, respectively, and the maximum reduction rate of the peak strain on the bottom of pier of the isolation model curved bridge was 43.4%. For the isolation model curved bridge, the maximum reduction rate of peak acceleration on the top of pier was 24.6% compared with that on the bottom of pier. The study results can provide experimental basis for the seismic design of curved bridges.

Neighborhood Bridges: 2010-2011 Evaluation Report

Science.gov (United States)

Ingram, Debra

2011-01-01

In 2010-2011, students in twenty-five classrooms from eleven schools in the Minneapolis-Saint Paul metropolitan area participated in The Children's Theatre Company's Neighborhood Bridges (Bridges) program. The Children's Theatre Company contracted with the University of Minnesota's Center for Applied Research and Educational Improvement (CAREI) to…

Ways of ensuring the standard of bridge superstructures.

Directory of Open Access Journals (Sweden)

M.G. Malgin

2011-12-01

Full Text Available The structural features of welded railway bridges of the last century were considered. The basic causes of appearance of fatigue cracks in welded joints of railway bridges were assessed. Structural and technological ways of provision of the design life of operated and new-built welded railway bridges are discussed.

Longest cable-stayed bridge TATARA; Longest shachokyo Tatara Ohashi

Energy Technology Data Exchange (ETDEWEB)

Fujii, K. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering

1998-06-15

The world`s longest cable-stayed bridge Tatara having a central span of 890 m had the both ends closed in August 1997, linking Namakuchi Island and Omishima Island. Final finishing work is continuing for opening of the West Seto Expressway in the spring of 1999. A cable-stayed bridge supports the bridge girders by perpendicular components of tensile force of cables stayed obliquely. On the other hand, there is a concern that the girders may have axial compression force generated due to horizontal components of the force from the cable tensile force, which can cause buckling of the girders. Therefore, in order to suspend the girders efficiently by increasing the perpendicular components of the cable force, and moreover to suppress the axial compression force on the girders, it is more advantageous to make bridge towers high, hence the towers of this bridge are highest among the bridges on the Shimanami Ocean Road. This bridge whose long girders are stayed with 21-stage multi cables presented a problem in designing the buckling in steel girders near the towers due to the horizontal components of the force generated by the bridge. Discussions were given, therefore, by using load withstanding force experiments using a whole bridge model of 1/50 scale, buckling experiments on full-size reinforcing plate models, and load withstanding force analysis using a tower model. A number of other technical discussions were repeated, by which the world`s longest cable-stayed bridge was completed. 9 figs., 1 tab.

Noise Considerations in Resistance Bridges

DEFF Research Database (Denmark)

Diamond, Joseph M.

1963-01-01

A signal-to-noise analysis is made of the Wheatstone bridge, where the unknown and standard resistors may be at different temperatures, a situation which occurs in resistance thermometry. The limiting condition is assumed to be dissipation in the unknown resistor. It is shown that the ratio arms...... thermometry, where the noise in the unknown resistor will predominate strongly. An impedance step-up device (transformer or tuned circuit) is valuable in raising the bridge signal and noise level above the noise of the first amplifier tube. However, as the step-up ratio is increased, two counterfactors appear....... With certain assumptions about the noise and grid current of the first tube it is found that the equivalent temperature of a unity ratio (Mueller) bridge used for liquid helium measurements may be 400°K....

T-section glulam timber bridge modules : modeling and performance

Science.gov (United States)

Paul A. Morgan; Steven E. Taylor; Michael A. Ritter; John M. Franklin

1999-01-01

This paper describes the design, modeling, and testing of two portable timber bridges, each consisting of two noninterconnected longitudinal glued-laminated timber (glulam) deck panels 1.8 m (6 ft) wide. One bridge is 12.2 m (40 ft) long while the other bridge is 10.7 m (35 ft) long. The deck panels are fabricated in a unique double-tee cross section. The bridges...

Safety analysis of passing maneuvers using extreme value theory

Directory of Open Access Journals (Sweden)

Haneen Farah

2017-04-01

The results indicate that this is a promising approach for safety evaluation. On-going work of the authors will attempt to generalize this method to other safety measures related to passing maneuvers, test it for the detailed analysis of the effect of demographic factors on passing maneuvers' crash probability and for its usefulness in a traffic simulation environment.

Effects of Irregular Bridge Columns and Feasibility of Seismic Regularity

Science.gov (United States)

Thomas, Abey E.

2018-05-01

Bridges with unequal column height is one of the main irregularities in bridge design particularly while negotiating steep valleys, making the bridges vulnerable to seismic action. The desirable behaviour of bridge columns towards seismic loading is that, they should perform in a regular fashion, i.e. the capacity of each column should be utilized evenly. But, this type of behaviour is often missing when the column heights are unequal along the length of the bridge, allowing short columns to bear the maximum lateral load. In the present study, the effects of unequal column height on the global seismic performance of bridges are studied using pushover analysis. Codes such as CalTrans (Engineering service center, earthquake engineering branch, 2013) and EC-8 (EN 1998-2: design of structures for earthquake resistance. Part 2: bridges, European Committee for Standardization, Brussels, 2005) suggests seismic regularity criterion for achieving regular seismic performance level at all the bridge columns. The feasibility of adopting these seismic regularity criterions along with those mentioned in literatures will be assessed for bridges designed as per the Indian Standards in the present study.

23 CFR 650.407 - Application for bridge replacement or rehabilitation.

Science.gov (United States)

2010-04-01

... 23 Highways 1 2010-04-01 2010-04-01 false Application for bridge replacement or rehabilitation... ENGINEERING AND TRAFFIC OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Highway Bridge Replacement and Rehabilitation Program § 650.407 Application for bridge replacement or rehabilitation. (a) Agencies participate...

Sensing and Rating of Vehicle–Railroad Bridge Collision

DEFF Research Database (Denmark)

Vemuganti, Shreya; Ozdagli, Ali I.; Liu, Bideng

2017-01-01

Overhead collisions of trucks with low-clearance railway bridges cause more than half of the railway traffic interruptions over bridges in the United States. Railroad owners are required to characterize the damage caused by such events and assess the safety of subsequent train crossings. However...... and remotely quantify damage. This research proposes an impact rating strategy based on the information that best describes the consequences of vehicle-railway bridge collisions. A series of representative impacts were simulated using numerical finite element models of a steel railway bridge. Railway owners...... provided information about the bridge and impact characterization based on railway industry experience. The resulting nonlinear dynamic responses were evaluated with the proposed rating strategy to assess the effect of these impacts. In addition, a neural network methodology was implemented on a simplified...

Bridge Creek IMW database - Bridge Creek Restoration and Monitoring Project

Data.gov (United States)

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

A fiber bridging model for fatigue delamination in composite materials

International Nuclear Information System (INIS)

Gregory, Jeremy R.; Spearing, S. Mark

2004-01-01

A fiber bridging model has been created to examine the effects of bridging on Mode I delamination fatigue fracture in a carbon fiber polymer-matrix composite. The model uses a cohesive zone law that is derived from quasi-static R-curves to determine the bridging energy applied in the bridged region. Timoshenko beam theory and an iterative self-consistent scheme are used to calculate the bridging tractions and displacements. After applying the bridging model to crack propagation data the scatter in the data was significantly reduced and clear trends were observed as a function of temperature that were not apparent previously. This indicated that the model appropriately accounted for the bridging in the experiments. Scanning electron microscopy crack opening displacement measurements were performed to validate the model's predictions. The measurements showed that the predictions were close to the actual bridging levels in the specimen

Low-sensitivity active filter realization using a complex all-pass filter

Science.gov (United States)

Regalia, Phillip A.; Mitra, Sanjit K.

1987-04-01

A wide class of continuous-time transfer functions may be implemented as the parallel combination of two all-pass filters, including Butterworth, Chebyshev, and elliptic low-pass approximations of odd order. Here, the realization of even-order low-pass classical approximations is considered, and it is shown that they may be decomposed in terms of complex all-pass functions. A systematic realization approach, based on scattering domain simulation (i.e., wave active filters), allows for a low-sensitivity active filter implementation. Further insight into the low-sensitivity property is gained by connecting the insertion loss of doubly terminated antimetric networks with the imaginary return loss of complex lossless networks.

An estimation of the exchange rate pass-through to prices in Mexico

OpenAIRE

Josué Fernando Cortés Espada

2013-01-01

This paper estimates the magnitude of the exchange rate pass-through to consumer prices in Mexico. Moreover, it analyzes if the pass-through dynamics have changed in recent years. In particular, it uses a methodology that generates results consistent with the hierarchy implicit in the CPI. The results suggest that the exchange rate pass-through to the general price level is low and not statistically significant. However, the pass-through is positive and significant for goods prices. Furthermo...

Magnetic fluid bridge in a non-uniform magnetic field

International Nuclear Information System (INIS)

Pelevina, D.A.; Naletova, V.A.; Turkov, V.A.

2017-01-01

The shape of a magnetic fluid bridge between a horizontal ferrite rod of circular cross-section and a horizontal plate above the rod in a vertical applied uniform magnetic field is studied. Various static shapes of the bridges are obtained theoretically and experimentally for the same magnetic field value. Abrupt changes and the hysteresis of the bridge shape in alternating magnetic fields are observed experimentally. - Highlights: • Magnetic fluid bridge between rod and horizontal plate in magnetic field is studied. • Magnetic field is created by a ferrite rod in a uniform vertical magnetic field. • Various static bridge shapes for fixed field are obtained in theory and experiment. • A good agreement of experimental and theoretical results is obtained. • Hysteresis of the bridge shape in alternating field is observed experimentally.

Magnetic fluid bridge in a non-uniform magnetic field

Energy Technology Data Exchange (ETDEWEB)

Pelevina, D.A., E-mail: pelevina.daria@gmail.com; Naletova, V.A.; Turkov, V.A.

2017-06-01

The shape of a magnetic fluid bridge between a horizontal ferrite rod of circular cross-section and a horizontal plate above the rod in a vertical applied uniform magnetic field is studied. Various static shapes of the bridges are obtained theoretically and experimentally for the same magnetic field value. Abrupt changes and the hysteresis of the bridge shape in alternating magnetic fields are observed experimentally. - Highlights: • Magnetic fluid bridge between rod and horizontal plate in magnetic field is studied. • Magnetic field is created by a ferrite rod in a uniform vertical magnetic field. • Various static bridge shapes for fixed field are obtained in theory and experiment. • A good agreement of experimental and theoretical results is obtained. • Hysteresis of the bridge shape in alternating field is observed experimentally.

Determining the Optimal Number of Core Needle Biopsy Passes for Molecular Diagnostics.

Science.gov (United States)

Hoang, Nam S; Ge, Benjamin H; Pan, Lorraine Y; Ozawa, Michael G; Kong, Christina S; Louie, John D; Shah, Rajesh P

2018-03-01

The number of core biopsy passes required for adequate next-generation sequencing is impacted by needle cut, needle gauge, and the type of tissue involved. This study evaluates diagnostic adequacy of core needle lung biopsies based on number of passes and provides guidelines for other tissues based on simulated biopsies in ex vivo porcine organ tissues. The rate of diagnostic adequacy for pathology and molecular testing from lung biopsy procedures was measured for eight operators pre-implementation (September 2012-October 2013) and post-implementation (December 2013-April 2014) of a standard protocol using 20-gauge side-cut needles for ten core biopsy passes at a single academic hospital. Biopsy pass volume was then estimated in ex vivo porcine muscle, liver, and kidney using side-cut devices at 16, 18, and 20 gauge and end-cut devices at 16 and 18 gauge to estimate minimum number of passes required for adequate molecular testing. Molecular diagnostic adequacy increased from 69% (pre-implementation period) to 92% (post-implementation period) (p < 0.001) for lung biopsies. In porcine models, both 16-gauge end-cut and side-cut devices require one pass to reach the validated volume threshold to ensure 99% adequacy for molecular characterization, while 18- and 20-gauge devices require 2-5 passes depending on needle cut and tissue type. Use of 20-gauge side-cut core biopsy needles requires a significant number of passes to ensure diagnostic adequacy for molecular testing across all tissue types. To ensure diagnostic adequacy for molecular testing, 16- and 18-gauge needles require markedly fewer passes.

Evaluating the life cycle environmental impact of short span bridges

DEFF Research Database (Denmark)

Du, Guangli; Pettersson, Lars; Karoumi, Raid

2016-01-01

impact of the construction sector. Life cycle assessment (LCA) is a systematic method for assessing the environmental impact of products and systems, but its application in bridges is scarce. In Swede, most of the bridges are short spans and the type of concrete slab-frame bridge (CFB) accounts...... for a large share. Soil steel composite bridge (SSCB) is a functional equivalent solution for CFB. In order to mitigate the environmental burdens of short span bridges, this paper performed a comparative LCA study between these two types of bridge. The results indicate that the initial material consumption...

A study on carbon nanotube bridge as a electromechanical memory device

Science.gov (United States)

Kang, Jeong Won; Ha Lee, Jun; Joo Lee, Hoong; Hwang, Ho Jung

2005-04-01

A nanoelectromechanical (NEM) nanotube random access memory (NRAM) device based on carbon nanotube (CNT) was investigated using atomistic simulations. For the CNT-based NEM memory, the mechanical properties of the CNT-bridge and van der Waals interactions between the CNT-bridge and substrate were very important. The critical amplitude of the CNT-bridge was 16% of the length of the CNT-bridge. As molecular dynamics time increased, the CNT-bridge went to the steady state under the electrostatic force with the damping of the potential and the kinetic energies of the CNT-bridge. The interatomic interaction between the CNT-bridge and substrate, value of the CNT-bridge slack, and damping rate of the CNT-bridge were very important for the operation of the NEM memory device as a nonvolatile memory.

BIM authoring for an image-based bridge maintenance system of existing cable-supported bridges

Science.gov (United States)

Dang, N. S.; Shim, C. S.

2018-04-01

Infrastructure nowadays is increasingly become the main backbone for the metropolitan development in general. Along with the rise of new facilities, the demand in term of maintenance for the existing bridges is indispensable. Recently, the terminology of “preventive maintenance” is not unfamiliar with the engineer, literally is the use of a bridge maintenance system (BMS) based on a BIM-oriented model. In this paper, the process of generating a BMS based on BIM model is introduced in detail. Data management for this BMS is separated into two modules: site inspection system and information management system. The noteworthy aspect of this model lays on the closed and automatic process of “capture image, generate the technical damage report, and upload/feedback to the BMS” in real-time. A pilot BMS system for a cable-supported bridge is presented which showed a good performance and potential to further development of preventive maintenance.

Own-Brand and Cross-Brand Retail Pass-Through

OpenAIRE

David Besanko; Jean-Pierre Dubé; Sachin Gupta

2005-01-01

In this paper we describe the pass-through behavior of a major U.S. supermarket chain for 78 products across 11 categories. Our data set includes retail prices and wholesale prices for stores in 15 retail price zones for a one-year period. For the empirical model, we use a reduced-form approach that focuses directly on equilibrium prices as a function of exogenous supply- and demand-shifting variables. The reduced-form approach enables us to identify the theoretical pass-through rate without ...

Myocardial bridges of the coronary arteries in the human fetal heart.

Science.gov (United States)

Cakmak, Yusuf Ozgür; Cavdar, Safiye; Yalin, Aymelek; Yener, Nuran; Ozdogmus, Omer

2010-09-01

During the last century, many investigators reported on myocardial bridges in the adult human heart. In the present study, 39 human fetal hearts (the mean gestastional age was 30 weeks) were studied for myocardial bridging, and the results were correlated with adult data. Among the 39 (27 male and 12 female) fetal hearts studied, 26 bridges were observed on 18 fetal hearts (46.2%). Ten of the bridges had one myocardial bridge, whereas double myocardial bridges were observed in eight fetal hearts. The most frequent myocardial bridges were observed on the left anterior descending artery (LAD), which had 13 bridges (50%). Eight (30.7%) myocardial bridges were on the diagonal artery, and on the posterior descending artery there were five (19.3%). Myocardial bridges were not observed on the circumflex artery. The data presented in this study may provide potentially useful information for the preoperative evaluation of the newborn and may have a clinical implication for sudden fetal death.

Overview of the National Timber Bridge Inspection Study

Science.gov (United States)

James P. Wacker; Brian K. Brashaw; Frank Jalinoos

2013-01-01

As many engineers begin to implement life cycle cost analyses within the preliminary bridge design phase, there is a significant need for more reliable data on the expected service life of highway bridges. Many claims are being made about the expected longevity of concrete and steel bridges, but few are based on actual performance data. Because engineers are least...

Collapse of the Tacoma· N arrows Bridge

Indian Academy of Sciences (India)

something was noticeably wrong with the bridge. The span ... So spectacular was the motion at times that the bridge was soon nicknamed Galloping. Gertie, and visitors ... A stranded car can be seen on the top right corner. ... home from Cal Tech a small rubber model of the bridge which one of my mechanics had made for ...

Generalizing Galileo's Passe-Dix Game

Science.gov (United States)

Hombas, Vassilios

2012-01-01

This article shows a generalization of Galileo's "passe-dix" game. The game was born following one of Galileo's [G. Galileo, "Sopra le Scoperte dei Dadi" (Galileo, Opere, Firenze, Barbera, Vol. 8). Translated by E.H. Thorne, 1898, pp. 591-594] explanations on a paradox that occurred in the experiment of tossing three fair "six-sided" dice.…

An expert system for the esthetic rating of bridges.

Science.gov (United States)

1990-01-01

The expert system presented should facilitate the in-depth analysis of bridge esthetics and encourage high standards for the appearance of bridges. The procedure described systematically evaluates features of a target bridge in relation to a similar ...

Implementation of sustainability in bridge design, construction and maintenance.

Science.gov (United States)

2012-12-01

The focus of this research is to develop a framework for more sustainable design and construction : processes for new bridges, and sustainable maintenance practices for existing bridges. The framework : includes a green rating system for bridges. The...

“On a bridge in Berlin”

DEFF Research Database (Denmark)

Pihl, Ole Verner

2013-01-01

This is a self-reflective case study based on the development of the Graphic Novel: “On a bridge in Berlin.” The GN will be used as an introduction to the history of architecture as a part of the curriculum in Architecture and Design at Aalborg University, and as a more broadly introduction...... that jumps in time and place: it begins with Martin Heidegger´s quotation “The Bridge gathers to itself in its own way earth and sky, divinities and mortals”, and the bridge is a state of mind, a chronotope, a portal in time between past, present, and future. The methodological approach is based...

Noise measurements on proximity effect bridges

International Nuclear Information System (INIS)

Decker, S.K.; Mercereau, J.E.

1975-01-01

Audio frequency noise density measurements were performed on weakly superconducting proximity effect bridges on using a cooled transformer and room temperature low noise preamplifier. The noise temperature of the measuring system is approximately 4 0 K for a 0.9 Ω resistor. Noise density was measured as a function of bias current and temperature for the bridges. Excess noise above that expected from Johnson noise for a resistor equal to the dynamic resistance of the bridges was observed in the region near the critical current of the device. At high currents compared to the critical current, the noise density closely approaches that given by Johnson noise

Heavy Vehicles on Minor Highway Bridges

DEFF Research Database (Denmark)

Kirkegaard, Poul Henning; Nielsen, Søren R. K.; Enevoldsen, I.

of heavier trucks moving at larger speeds, and partly because the authorities want to permit transportation of special heavy goods at a larger part of the road net. These needs will in many cases cause the strengthening of the bridges becomes necessary. In order to keep the expenses of such strengthening...... the results obtained using the numerical models given in details in "Heavy Vehicles on Minor Highway Bridges : dynamic modelling of vehicles and bridges". The models are established using a ordinary vehicle which consists of a 48 t Scania with a 3 axle tractor and a 3 axle trailer, joined in a flexible hinge...

Two-pass greedy regular expression parsing

DEFF Research Database (Denmark)

Grathwohl, Niels Bjørn Bugge; Henglein, Fritz; Nielsen, Lasse

2013-01-01

We present new algorithms for producing greedy parses for regular expressions (REs) in a semi-streaming fashion. Our lean-log algorithm executes in time O(mn) for REs of size m and input strings of size n and outputs a compact bit-coded parse tree representation. It improves on previous algorithms...... by: operating in only 2 passes; using only O(m) words of random-access memory (independent of n); requiring only kn bits of sequentially written and read log storage, where k ... and not requiring it to be stored at all. Previous RE parsing algorithms do not scale linearly with input size, or require substantially more log storage and employ 3 passes where the first consists of reversing the input, or do not or are not known to produce a greedy parse. The performance of our unoptimized C...

Super-bridges suspended over carbon nanotube cables

Science.gov (United States)

Carpinteri, Alberto; Pugno, Nicola M.

2008-11-01

In this paper the new concept of 'super-bridges', i.e. kilometre-long bridges suspended over carbon nanotube cables, is introduced. The analysis shows that the use of realistic (thus defective) carbon nanotube bundles as suspension cables can enlarge the current limit main span by a factor of ~3. Too large compliance and dynamic self-excited resonances could be avoided by additional strands, rendering the super-bridge anchored as a spider's cobweb. As an example, we have computed the limit main spans of the current existing 19 suspended-deck bridges longer than 1 km assuming them to have substituted their cables with carbon nanotube bundles (thus maintaining the same geometry, with the exception of the length) finding spans of up to ~6.3 km. We thus suggest that the design of the Messina bridge in Italy, which would require a main span of ~3.3 km, could benefit from the use of carbon nanotube bundles. We believe that their use represents a feasible and economically convenient solution. The plausibility of these affirmations is confirmed by a statistical analysis of the existing 100 longest suspended bridges, which follow a Zipf's law with an exponent of 1.1615: we have found a Moore-like (i.e. exponential) law, in which the doubling of the capacity (here the main span) per year is substituted by the factor 1.0138. Such a law predicts that the realization of the Messina bridge using conventional materials will only occur around the middle of the present century, whereas it could be expected in the near future if carbon nanotube bundles were used. A simple cost analysis concludes the paper.

Super-bridges suspended over carbon nanotube cables

International Nuclear Information System (INIS)

Carpinteri, Alberto; Pugno, Nicola M

2008-01-01

In this paper the new concept of 'super-bridges', i.e. kilometre-long bridges suspended over carbon nanotube cables, is introduced. The analysis shows that the use of realistic (thus defective) carbon nanotube bundles as suspension cables can enlarge the current limit main span by a factor of ∼3. Too large compliance and dynamic self-excited resonances could be avoided by additional strands, rendering the super-bridge anchored as a spider's cobweb. As an example, we have computed the limit main spans of the current existing 19 suspended-deck bridges longer than 1 km assuming them to have substituted their cables with carbon nanotube bundles (thus maintaining the same geometry, with the exception of the length) finding spans of up to ∼6.3 km. We thus suggest that the design of the Messina bridge in Italy, which would require a main span of ∼3.3 km, could benefit from the use of carbon nanotube bundles. We believe that their use represents a feasible and economically convenient solution. The plausibility of these affirmations is confirmed by a statistical analysis of the existing 100 longest suspended bridges, which follow a Zipf's law with an exponent of 1.1615: we have found a Moore-like (i.e. exponential) law, in which the doubling of the capacity (here the main span) per year is substituted by the factor 1.0138. Such a law predicts that the realization of the Messina bridge using conventional materials will only occur around the middle of the present century, whereas it could be expected in the near future if carbon nanotube bundles were used. A simple cost analysis concludes the paper.

Long-term behavior of integral abutment bridges : [technical summary].

Science.gov (United States)

2011-01-01

Integral abutment bridges, a type of jointless bridge, are the construction option of choice when designing highway bridges in many parts of the country. Rather than providing an expansion joint to separate the substructure from the superstructure to...

Simple model of cable-stayed bridge deck subjected to static wind loading

Science.gov (United States)

Kang, Yi-Lung; Wang, Yang Cheng

1997-05-01

Cable-stayed bridges have been known since 18th century with aesthetics design. The structural system and the structural behavior are significantly different from those of continuous bridges. Compared to continuous bridge, cable- stayed bridges have more flexure bridge deck than those of continuous bridges.On the other hand, cable-stayed bridges have less stiffness to resist wind loading especially for lateral loads. The first considering of bridge engineering is safety. In 1940's, Tacoma Narrows Suspension Bridge destroyed by wind loading is a good example even though it is not a cable-stayed bridge. After the bridge was destroyed, a lot of research articles have been published regarding cable supported bridge subjected to wind loading. In recent days, high strength materials have been served. The bridge engineers use the advantages to expand the span length of cable-stayed bridges. Due to the span length increased and the use of high strength materials, cable- stayed bridges have more significant nonlinear behavior subjected to wind loading. In this paper, a slice bridge deck of cable-stayed bridge connected to internal support cables is considered. The deck has been considered to be subjected to lateral static wind loading. Since cables can not take compressive force, the deck has strongly nonlinear behavior even though the materials are linear elastic. Several primary load combinations have ben considered in this paper such as the bridge deck supposed to be moved horizontally without rotation or the bridge deck supposed to be moved horizontally with rotational deformation. The mathematical formulas and the numerical solutions are found and represented in graphical forms. The results can be provided to bridge designers and researchers for further study of this type of structure subjected to wind loading.

Monitoring Bridge Dynamic Deformation in Vibration by Digital Photography

Science.gov (United States)

Yu, Chengxin; Zhang, Guojian; Liu, Xiaodong; Fan, Li; Hai, Hua

2018-01-01

This study adopts digital photography to monitor bridge dynamic deformation in vibration. Digital photography in this study is based on PST-TBPM (photographing scale transformation-time baseline parallax method). Firstly, we monitor the bridge in static as a zero image. Then, we continuously monitor the bridge in vibration as the successive images. Based on the reference points on each image, PST-TBPM is used to calculate the images to obtain the dynamic deformation values of these deformation points. Results show that the average measurement accuracies are 0.685 pixels (0.51mm) and 0.635 pixels (0.47mm) in X and Z direction, respectively. The maximal deformations in X and Z direction of the bridge are 4.53 pixels and 5.21 pixels, respectively. PST-TBPM is valid in solving the problem that the photographing direction is not perpendicular to the bridge. Digital photography in this study can be used to assess bridge health through monitoring the dynamic deformation of a bridge in vibration. The deformation trend curves also can warn the possible dangers over time.

33 CFR 115.30 - Sufficiency of State authority for bridges.

Science.gov (United States)

2010-07-01

... for bridges. 115.30 Section 115.30 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES BRIDGE LOCATIONS AND CLEARANCES; ADMINISTRATIVE PROCEDURES § 115.30 Sufficiency of State authority for bridges. An opinion of the attorney general of the State as to the sufficiency of State...

Application of Artificial Intelligence for Bridge Deterioration Model

Directory of Open Access Journals (Sweden)

Zhang Chen

2015-01-01

Full Text Available The deterministic bridge deterioration model updating problem is well established in bridge management, while the traditional methods and approaches for this problem require manual intervention. An artificial-intelligence-based approach was presented to self-updated parameters of the bridge deterioration model in this paper. When new information and data are collected, a posterior distribution was constructed to describe the integrated result of historical information and the new gained information according to Bayesian theorem, which was used to update model parameters. This AI-based approach is applied to the case of updating parameters of bridge deterioration model, which is the data collected from bridges of 12 districts in Shanghai from 2004 to 2013, and the results showed that it is an accurate, effective, and satisfactory approach to deal with the problem of the parameter updating without manual intervention.

Bridge Management Strategy Based on Extreme User Costs for Bridge Network Condition

Directory of Open Access Journals (Sweden)

Ladislaus Lwambuka

2014-01-01

Full Text Available This paper presents a practical approach for prioritization of bridge maintenance within a given bridge network. The maintenance prioritization is formulated as a multiobjective optimization problem where the simultaneous satisfaction of several conflicting objectives includes minimization of maintenance costs, maximization of bridge deck condition, and minimization of traffic disruption and associated user costs. The prevalence of user cost during maintenance period is twofold; the first case refers to the period of dry season where normally the traffic flow is diverted to alternative routes usually resurfaced to regain traffic access. The second prevalence refers to the absence of alternative routes which is often the case in the least developed countries; in this case the user cost referred to results from the waiting time while the traffic flow is put on hold awaiting accomplishment of the maintenance activity. This paper deals with the second scenario of traffic closure in the absence of alternative diversion routes which in essence results in extreme user cost. The paper shows that the multiobjective optimization approach remains valid for extreme cases of user costs in the absence of detour roads as often is the scenario in countries with extreme poor road infrastructure.

Analysis of CMOS Compatible Cu-Based TM-Pass Optical Polarizer

KAUST Repository

Ng, Tien Khee

2012-02-10

A transverse-magnetic-pass (TM-pass) optical polarizer based on Cu complementary metal-oxide-semiconductor technology platform is proposed and analyzed using the 2-D method-of-lines numerical model. In designing the optimum configuration for the polarizer, it was found that the metal-insulator-metal (MIM) polarizer structure is superior compared to the insulator-metal-insulator polarizer structure due to its higher polarization extinction ratio (PER) and low insertion loss. An optimized MIM TM-pass polarizer exhibits simulated long wavelength pass filter characteristics of > ?1.2 ?m, with fundamental TM 0 and TE 0 mode transmissivity of >70% and <5%, respectively, and with PER ?11.5 dB in the wavelength range of 1.2-1.6 ?m. The subwavelength and submicrometer features of this TM-polarizer are potentially suitable for compact and low power photonics integrated circuit implementation on silicon-based substrates. © 1989-2012 IEEE.

Guardrails for Use on Historic Bridges: Volume 1—Replacement Strategies

OpenAIRE

Frosch, Robert J.; Kreger, Michael E.; Clauss, Adam J.

2016-01-01

Bridges that are designated historic present a special challenge to bridge engineers whenever rehabilitation work or improvements are made to the bridges. Federal and state laws protect historically significant bridges, and railings on these bridges can be subject to protection because of the role they play in aesthetics. Unfortunately, original railings on historic bridges do not typically meet current crash-test requirements and typically do not meet current standards for railing height and...

Exploring the relevance of thiophene rings as bridge unit in acceptor-bridge-donor dyes on self-aggregation and performance in DSSCs.

Science.gov (United States)

Zarate, Ximena; Saavedra-Torres, Mario; Rodriguez-Serrano, Angela; Gomez, Tatiana; Schott, Eduardo

2018-04-30

The possibility of dye charge recombination in DSSCs remains a challenge for the field. This consists of: (a) back-transfer from the TiO 2 to the oxidized dye and (b) intermolecular electron transfer between dyes. The latter is attributed to dye aggregation due to dimeric conformations. This leads to poor electron injection which decreases the photocurrent conversion efficiency. Most organic sensitizers are characterized by an Acceptor-Bridge-Donor (A-Bridge-D) arrangement that is commonly employed to provide charge separation and, therefore, lowering the unwanted back-transfer. Here, we address the intermolecular electron transfer by studying the dimerization and photovoltaic performance of a group of A-Bridge-D structured dyes. Specifically, eight famous sulfur containing π-bridges were analyzed (A and D remained fixed). Through quantum mechanical and molecular dynamics approaches, it was found that the formation of weakly stabilized dimers is allowed. The dyes with covalently bonded and fused thiophene rings as Bridges, 6d and 7d as well as 8d with a fluorene, would present high aggregation and, therefore, high probability of recombination processes. Conversely, using TiO 2 cluster and surface models, delineated the shortest bridges to improve the adsorption energy and the stability of the system. Finally, the elongation of the bridge up to 2 and 3 units and their photovoltaic parameters were studied. These results showed that all the sensitizers are able to provide similar photocurrent outcomes, regardless of whether the bridge is elongated. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Verification of LRFD Bridge Design and Analysis Software for INDOT

OpenAIRE

Varma, Amit H.; Seo, Jungil

2009-01-01

NCHRP Process 12-50 was implemented to evaluate and verify composite steel I-girder bridge design software used commonly in Indiana. A test-bed of twenty one bridges was developed with the guidance from an Indiana Department of Transportation appointed research advisory panel (RAP). The test-bed included five simple-span and sixteen multi-span bridge superstructures. More than 80 parameters were required to define a bridge and they include bridge span, girder spacing, number of beams, section...

Expected damages of retrofitted bridges with RC jacketing

Science.gov (United States)

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

2015-07-01

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

Expected damages of retrofitted bridges with RC jacketing

International Nuclear Information System (INIS)

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

2015-01-01

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

Pilot testing of a hydraulic bridge exciter

Directory of Open Access Journals (Sweden)

Andersson Andreas

2015-01-01

Full Text Available This paper describes the development of a hydraulic bridge exciter and its first pilot testing on a full scale railway bridge in service. The exciter is based on a hydraulic load cylinder with a capacity of 50 kN and is intended for controlled dynamic loading up to at least 50 Hz. The load is applied from underneath the bridge, enabling testing while the railway line is in service. The system is shown to produce constant load amplitude even at resonance. The exciter is used to experimentally determine frequency response functions at all sensor locations, which serve as valuable input for model updating and verification. An FE-model of the case study bridge has been developed that is in good agreement with the experimental results.

Post-Earthquake Traffic Capacity of Modern Bridges in California

Science.gov (United States)

2010-03-01

Evaluation of the capacity of a bridge to carry self-weight and traffic loads after an earthquake is essential for a : safe and timely re-opening of the bridge. In California, modern highway bridges designed using the Caltrans : Seismic Design Criter...

Detection of salt bridges to lysines in solution in barnase

DEFF Research Database (Denmark)

Hansen, Poul Erik; Williamson, Michael P.; Hounslow, Andrea M.

2013-01-01

We show that salt bridges involving lysines can be detected by deuterium isotope effects on NMR chemical shifts of the sidechain amine. Lys27 in the ribonuclease barnase is salt bridged, and mutation of Arg69 to Lys retains a partially buried salt bridge. The salt bridges are functionally important....

How to pass higher English colour

CERN Document Server

Bridges, Ann

2009-01-01

How to Pass is the Number 1 revision series for Scottish qualifications across the three examination levels of Standard Grade, Intermediate and Higher! Second editions of the books present all of the material in full colour for the first time.

Fabrication of ultrashort niobium variable-thickness bridges

International Nuclear Information System (INIS)

Goto, T.

1982-01-01

A simple technique for the fabrication of niobium variable-thickness bridges of length approx.0.1 μm is described. The bridges are found to operate as ideal Josephson junctions over a wide temperature range

JEMMRLA - Electron Model of a Muon RLA with Multi-pass Arcs

Energy Technology Data Exchange (ETDEWEB)

Bogacz, Slawomir Alex; Krafft, Geoffrey A.; Morozov, Vasiliy S.; Roblin, Yves R.

2013-06-01

We propose a demonstration experiment for a new concept of a 'dogbone' RLA with multi-pass return arcs -- JEMMRLA (Jlab Electron Model of Muon RLA). Such an RLA with linear-field multi-pass arcs was introduced for rapid acceleration of muons for the next generation of Muon Facilities. It allows for efficient use of expensive RF while the multi-pass arc design based on linear combined-function magnets exhibits a number of advantages over separate-arc or pulsed-arc designs. Here we describe a test of this concept by scaling a GeV scale muon design for electrons. Scaling muon momenta by the muon-to-electron mass ratio leads to a scheme, in which a 4.5 MeV electron beam is injected in the middle of a 3 MeV/pass linac with two double-pass return arcs and is accelerated to 18 MeV in 4.5 passes. All spatial dimensions including the orbit distortion are scaled by a factor of 7.5, which arises from scaling the 200 MHz muon RF to a readily available 1.5 GHz. The hardware requirements are not very demanding making it straightforward to implement. Such an RLA may have applications going beyond muon acceleration: in medical isotope production, radiation cancer therapy and homeland security.

Performance of single-pass and by-pass multi-step multi-soil-layering systems for low-(C/N)-ratio polluted river water treatment.

Science.gov (United States)

Wei, Cai-Jie; Wu, Wei-Zhong

2018-09-01

Two kinds of hybrid two-step multi-soil-layering (MSL) systems loaded with different filter medias (zeolite-ceramsite MSL-1 and ceramsite-red clay MSL-2) were set-up for the low-(C/N)-ratio polluted river water treatment. A long-term pollutant removal performance of these two kinds of MSL systems was evaluated for 214 days. By-pass was employed in MSL systems to evaluate its effect on nitrogen removal enhancement. Zeolite-ceramsite single-pass MSL-1 system owns outstanding ammonia removal capability (24 g NH 4 + -Nm -2 d -1 ), 3 times higher than MSL-2 without zeolite under low aeration rate condition (0.8 × 10 4  L m -2 .h -1 ). Aeration rate up to 1.6 × 10 4  L m -2 .h -1 well satisfied the requirement of complete nitrification in first unit of both two MSLs. However, weak denitrification in second unit was commonly observed. By-pass of 50% influent into second unit can improve about 20% TN removal rate for both MSL-1 and MSL-2. Complete nitrification and denitrification was achieved in by-pass MSL systems after addition of carbon source with the resulting C/N ratio up to 2.5. The characters of biofilms distributed in different sections inside MSL-1 system well illustrated the nitrogen removal mechanism inside MSL systems. Two kinds of MSLs are both promising as an appealing nitrifying biofilm reactor. Recirculation can be considered further for by-pass MSL-2 system to ensure a complete ammonia removal. Copyright © 2018 Elsevier Ltd. All rights reserved.

Bridging the Gap (BRIEFING CHARTS)

Science.gov (United States)

2007-03-05

1 Defense Advanced Research Projects Agency “Bridging the Gap ” Dr. Robert F. Leheny Deputy Director Report Documentation Page Form ApprovedOMB No...comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to...4. TITLE AND SUBTITLE Bridging the Gap 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER

Multi-Hazard Assessment of Scour Damaged Bridges with UAS-Based Measurements

Science.gov (United States)

Özcan, O.; Ozcan, O.

2017-12-01

Flood and stream induced scour occurring in bridge piers constructed on rivers is one of the mostly observed failure reasons in bridges. Scour induced failure risk in bridges and determination of the alterations in bridge safety under seismic effects has the ultimate importance. Thus, for the determination of bridge safety under the scour effects, the scour amount under bridge piers should be designated realistically and should be tracked and updated continuously. Hereby, the scour induced failures in bridge foundation systems will be prevented and bridge substructure design will be conducted safely. In this study, in order to measure the amount of scour in bridge load bearing system (pile foundations and pile abutments) and to attain very high definition 3 dimensional models of river flood plain for the flood analysis, unmanned aircraft system (UAS) based measurement methods were implemented. UAS based measurement systems provide new and practical approach and bring high precision and reliable solutions considering recent measurement systems. For this purpose, the reinforced concrete (RC) bridge that is located on Antalya Boğaçayı River, Turkey and that failed in 2003 due to flood-induced scour was selected as the case study. The amount of scour occurred in bridge piers and piles was determined realistically and the behavior of bridge piers under scour effects was investigated. Future flood effects and the resultant amount of scour was determined with HEC-RAS software by using digital surface models that were obtained at regular intervals using UAS for the riverbed. In the light of the attained scour measurements and expected scour after a probable flood event, the behavior of scour damaged RC bridge was investigated by pushover and time history analyses under lateral and vertical seismic loadings. In the analyses, the load and displacement capacity of bridge was observed to diminish significantly under expected scour. Thus, the deterioration in multi hazard

Development of a numerical model for vehicle-bridge interaction analysis of railway bridges

Science.gov (United States)

Kim, Hee Ju; Cho, Eun Sang; Ham, Jun Su; Park, Ki Tae; Kim, Tae Heon

2016-04-01

In the field of civil engineering, analyzing dynamic response was main concern for a long time. These analysis methods can be divided into moving load analysis method and moving mass analysis method, and formulating each an equation of motion has recently been studied after dividing vehicles and bridges. In this study, the numerical method is presented, which can consider the various train types and can solve the equations of motion for a vehicle-bridge interaction analysis by non-iteration procedure through formulating the coupled equations for motion. Also, 3 dimensional accurate numerical models was developed by KTX-vehicle in order to analyze dynamic response characteristics. The equations of motion for the conventional trains are derived, and the numerical models of the conventional trains are idealized by a set of linear springs and dashpots with 18 degrees of freedom. The bridge models are simplified by the 3 dimensional space frame element which is based on the Euler-Bernoulli theory. The rail irregularities of vertical and lateral directions are generated by PSD functions of the Federal Railroad Administration (FRA).

Guide for In-Place Treatment of Covered and Timber Bridges

Science.gov (United States)

Stan Lebow; Grant Kirker; Robert White; Terry Amburgey; H. Michael Barnes; Michael Sanders; Jeff Morrell

2012-01-01

Historic covered bridges and current timber bridges can be vulnerable to damage from biodeterioration or fire. This guide describes procedures for selecting and applying in-place treatments to prevent or arrest these forms of degradation. Vulnerable areas for biodeterioration in covered bridges include members contacting abutments, members near the ends of bridges...

Risk Mitigation for Highway and Railway Bridges

Science.gov (United States)

2009-02-01

Performance of the transportation network strongly depends on the performance of bridges. Bridges constitute a vital part of the transportation infrastructure system and they are vulnerable to extreme events such as natural disasters (i.e., hurricane...

Development and validation of deterioration models for concrete bridge decks - phase 1 : artificial intelligence models and bridge management system.

Science.gov (United States)

2013-06-01

This research documents the development and evaluation of artificial neural network (ANN) models to predict the condition ratings of concrete highway bridge decks in Michigan. Historical condition assessments chronicled in the national bridge invento...

Visualization of mcr mRNA in a methanogen by fluorescence in situ hybridization with an oligonucleotide probe and two-pass tyramide signal amplification (two-pass TSA-FISH).

Science.gov (United States)

Kubota, Kengo; Ohashi, Akiyoshi; Imachi, Hiroyuki; Harada, Hideki

2006-09-01

Two-pass tyramide signal amplification-fluorescence in situ hybridization (two-pass TSA-FISH) with a horseradish peroxidase (HRP)-labeled oligonucleotide probe was applied to detect prokaryotic mRNA. In this study, mRNA of a key enzyme for methanogenesis, methyl coenzyme M reductase (mcr), in Methanococcus vannielii was targeted. Applicability of mRNA-targeted probes to in situ hybridization was verified by Clone-FISH. It was observed that sensitivity of two-pass TSA-FISH was significantly higher than that of TSA-FISH, which was further increased by the addition of dextran sulphate in TSA working solution. Signals from two-pass TSA-FISH were more reliable compared to the weak, spotty signals yielded by TSA-FISH.

Bridge Condition Assessment based on Vibration Responses of Passenger Vehicle

International Nuclear Information System (INIS)

Miyamoto, Ayaho; Yabe, Akito

2011-01-01

In this paper, we propose a new method of assessing the condition of existing short- and medium-span reinforced/prestressed concrete bridges based on vibration monitoring data obtained from a public bus. This paper not only describes details of a prototype monitoring system that uses information technology and sensors capable of providing more accurate knowledge of bridge performance than conventional ways but also shows a few specific examples of bridge condition assessment based on vehicle vibrations measured by using an in-service public bus equipped with vibration measurement instrumentation. This paper also describes a sensitivity analysis of deteriorating bridges based on simulation of the acceleration response of buses conducted by the 'substructure method' employing a finite element model to verify the above bridge performance results. The main conclusions obtained in this study can be summarized as follows: (1) Because the vibration responses of passenger vehicles, such as buses, have a good linear relationship with the vibration responses of the target bridges, the proposed system can be used as a practical monitoring system for bridge condition assessment. (2) The results of sensitivity analysis performed by the substructure method show that bus vibration responses are useful for evaluating target bridge performance. (3) The proposed method was applied to a network of real bridges in a local area to evaluate its effectiveness. The results indicate that the proposed method can be used to prioritize the repair/strengthening works of existing bridges based on various vibration information in order to help bridge administrators establish rational maintenance strategies.

Bridge scour countermeasure assessments at select bridges in the United States, 2014–16

Science.gov (United States)

Dudunake, Taylor J.; Huizinga, Richard J.; Fosness, Ryan L.

2017-05-23

In 2009, the Federal Highway Administration published Hydraulic Engineering Circular No. 23 (HEC-23) to provide specific design and implementation guidelines for bridge scour and stream instability countermeasures. However, the effectiveness of countermeasures implemented over the past decade following those guidelines has not been evaluated. Therefore, in 2013, the U.S. Geological Survey, in cooperation with the Federal Highway Administration, began a study to assess the current condition of bridge-scour countermeasures at selected sites to evaluate their effectiveness. Bridge-scour countermeasures were assessed during 2014-2016. Site assessments included reviewing countermeasure design plans, summarizing the peak and daily streamflow history, and assessments at each site. Each site survey included a photo log summary, field form, and topographic and bathymetric geospatial data and metadata. This report documents the study area and site-selection criteria, explains the survey methods used to evaluate the condition of countermeasures, and presents the complete documentation for each countermeasure assessment.

Reserves in load capacity assessment of existing bridges

Science.gov (United States)

Žitný, Jan; Ryjáček, Pavel

2017-09-01

High percentage of all railway bridges in the Czech Republic is made of structural steel. Majority of these bridges is designed according to historical codes and according to the deterioration, they have to be assessed if they satisfy the needs of modern railway traffic. The load capacity assessment of existing bridges according to Eurocodes is however often too conservative and especially, braking and acceleration forces cause huge problems to structural elements of the bridge superstructure. The aim of this paper is to review the different approaches for the determination of braking and acceleration forces. Both, current and historical theoretical models and in-situ measurements are considered. The research of several local European state norms superior to Eurocode for assessment of existing railway bridges shows the big diversity of used local approaches and the conservativeness of Eurocode. This paper should also work as an overview for designers dealing with load capacity assessment, revealing the reserves for existing bridges. Based on these different approaches, theoretical models and data obtained from the measurements, the method for determination of braking and acceleration forces on the basis of real traffic data should be proposed.

Square function analysis of the Inductor-Converter Bridge

International Nuclear Information System (INIS)

Ehsani, M.; Kustom, R.L.

1979-03-01

The transfer of energy between two superconducting coils can be controlled with an Inductor-Converter Bridge (ICB) by changing the relative timing between the storage side bridge and the load side bridge. The average voltages on the coils have been previously derived as a function of relative timing between the two halves of the bridges and the relative currents in the two coils using a one-line, harmonic current source representation of each coil and its bridge network. Since the coil current in each of the ICB phases appears as bipolar rectangular pulses, an analysis based on unit step functions has been developed. The unit step function analysis leads to simple polynomial expressions relating the average coil voltages to relative timing. The new derivations are shown to have the same harmonic representation as previously developed. The polynomial expressions are more compatible to microprocessor control than are the harmonic function expressions

Design and construction of the Natorigawa Bridge; Natorigawa kyoryo no sekkei/seko

Energy Technology Data Exchange (ETDEWEB)

Murai, Y.; Oba, M.; Omurata, Y. [JR East Japan Railway Co., Tokyo (Japan); Miyauchi, M.; Iwasaki, I. [Taisei Corp., Tokyo (Japan)

1997-03-31

The Natorigawa Bridge is reconstructed. Out of the reconstruction work, a report is made mainly on the design of the superstructure work of the PC panel-stayed bridge and the details of the work. In selecting bridge type, PC simple through beam bridge, steel trussed bridge, PC cable-stayed bridge, and PC panel-stayed bridge are compared, and a 2-span continuous PC panel-stayed bridge is adopted. Its appearance resembles that of the cable-stayed bridge, but the structure resembles a girder bridge. The appropriate span length is the intermediate range between those of the girder bridge and the cable-stayed bridge. Its trafficability is excellent with little deformation by the running of trains because the main beam, diagonal panel, and the main tower are connected rigidly to provide high rigidity of the entire bridge. PRC structure is employed in consideration of the restriction to beam height and economical efficiency. Analyses by a FEM model using two dimensional plane elements and by a few plane frame models as well as comparison of sectional force are performed for this bridge, and a proper plane model is selected. Substructure work, superstructure work and measurement work are described. 3 refs., 16 figs., 6 tabs.

Structural condition assessment of the bridge in Ostrava

Directory of Open Access Journals (Sweden)

Čech Jindřich

2017-01-01

Full Text Available This paper deals with the comparison of results of dynamic test and numerical modelling of a road bridge across the Dr. Kudela street in the street Rudná in Ostrava. The bridge is a reinforced concrete structure, made of post-tensioned KA-beams. On the bridge were verified material properties. Calculation model to validate the static and dynamic behavior of structures was created. On the bridge were measured dynamic properties (frequency, mode shapes and attenuation during excitation construction by hydraulic vibration exciter. Article will focus on comparing the results of the calculation of dynamic structures and properties measured on real structure upon excitation.

Analytical investigation of bidirectional ductile diaphragms in multi-span bridges

Science.gov (United States)

Wei, Xiaone; Bruneau, Michel

2018-04-01

In the AASHTO Guide Specifications for Seismic Bridge Design Provisions, ductile diaphragms are identified as Permissible Earthquake-Resisting Elements (EREs), designed to help resist seismic loads applied in the transverse direction of bridges. When adding longitudinal ductile diaphragms, a bidirectional ductile diaphragm system is created that can address seismic excitations acting along both the bridge's longitudinal and transverse axes. This paper investigates bidirectional ductile diaphragms with Buckling Restrained Braces (BRBs) in straight multi-span bridge with simply supported floating spans. The flexibility of the substructures in the transverse and longitudinal direction of the bridge is considered. Design procedures for the bidirectional ductile diaphragms are first proposed. An analytical model of the example bridge with bidirectional ductile diaphragms, designed based on the proposed methodology, is then built in SAP2000. Pushover and nonlinear time history analyses are performed on the bridge model, and corresponding results are presented. The effect of changing the longitudinal stiffness of the bidirectional ductile diaphragms in the end spans connecting to the abutment is also investigated, in order to better understand the impact on the bridge's dynamic performance.

Message passing with parallel queue traversal

Science.gov (United States)

Underwood, Keith D [Albuquerque, NM; Brightwell, Ronald B [Albuquerque, NM; Hemmert, K Scott [Albuquerque, NM

2012-05-01

In message passing implementations, associative matching structures are used to permit list entries to be searched in parallel fashion, thereby avoiding the delay of linear list traversal. List management capabilities are provided to support list entry turnover semantics and priority ordering semantics.

Geometry dependence of the magnetization reversal process in bridged dots

International Nuclear Information System (INIS)

Escobar, R.A.; Lage, E.; D’Albuquerque e Castro, J.; Altbir, D.; Ross, C.A.

2017-01-01

Based on Monte Carlo numerical simulations: results for the magnetization reversal process in thin circular Ni dots connected by a bridge are presented. The dependence of the process on both the width of the bridge and the orientation of the applied magnetic field has been investigated. It was found that when the applied magnetic field is set parallel to the bridge, the hysteresis curves are weakly dependent on the width of the bridge, being rather close to that of a single dot of the same diameter. On the other hand, when the magnetic field is applied perpendicularly to the bridge, a significant reduction in the coercivity of the system is obtained, even in the case of narrower bridges.

Geometry dependence of the magnetization reversal process in bridged dots

Energy Technology Data Exchange (ETDEWEB)

Escobar, R.A. [Departamento de Física, CEDENNA, Universidad de Santiago de Chile, USACH, Av. Ecuador 3493, Santiago (Chile); Lage, E. [Department of Materials Science and Engineering, Massachusetts Institute of Technology, 02139 Cambridge, MA (United States); D’Albuquerque e Castro, J. [Instituto de Física, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro, RJ 21945-970 (Brazil); Altbir, D., E-mail: dora.altbir@usach.cl [Departamento de Física, CEDENNA, Universidad de Santiago de Chile, USACH, Av. Ecuador 3493, Santiago (Chile); Ross, C.A. [Department of Materials Science and Engineering, Massachusetts Institute of Technology, 02139 Cambridge, MA (United States)

2017-06-15

Based on Monte Carlo numerical simulations: results for the magnetization reversal process in thin circular Ni dots connected by a bridge are presented. The dependence of the process on both the width of the bridge and the orientation of the applied magnetic field has been investigated. It was found that when the applied magnetic field is set parallel to the bridge, the hysteresis curves are weakly dependent on the width of the bridge, being rather close to that of a single dot of the same diameter. On the other hand, when the magnetic field is applied perpendicularly to the bridge, a significant reduction in the coercivity of the system is obtained, even in the case of narrower bridges.

Renovation techniques for fatigue cracked orthotropic steel bridge decks

NARCIS (Netherlands)

de Jong, F.B.P.

2007-01-01

This dissertation presents the research into renovation techniques for orthotropic steel bridge decks. These techniques are needed to solve fatigue problems in the decks of these bridges, as several fatigue cracks have been detected in the deck structure of these bridges the last decade. A

PARAMETRIC STUDY OF SKEW ANGLE ON BOX GIRDER BRIDGE DECK

OpenAIRE

Shrikant D. Bobade *, Dr. Valsson Varghese

2016-01-01

Box girder bridge deck, is the most common type of bridges in world and India, it consists of several Slab or girders. The span in the direction of the roadway and connected across their tops and bottoms by a thin continuous structural stab, the longitudinal box girders can be made of steel or concrete. The Simple supported single span concrete bridge deck is presented in present study. Skewed bridges are suitable in highway design when the geometry of straight bridges is not possible. The sk...

Derivation of Oscillators from Biquadratic Band Pass Filters Using Circuit Transformations

Directory of Open Access Journals (Sweden)

Hung-Yu Wang

2014-09-01

Full Text Available Network transformations are the techniques to obtain new functional schemes from available circuits. They are systematic methodologies, since each transformation technique can be applied to many circuits to obtain the desired functions or characteristics. A convenient network transformation method, exploiting different circuit transformations, for deriving linear sinusoidal oscillators from biquadratic band pass filters is proposed. This method with generality can be applied to any band pass filter. The oscillation frequency of the new obtained oscillator is identical to the center frequency of the original band pass filter, and the useful properties of the selected band pass filter can be retained. Two examples are illustrated to confirm the feasibility of the proposed approach. The workability of the obtained oscillators is verified with PSPICE simulations.

Delay Bound: Fractal Traffic Passes through Network Servers

Directory of Open Access Journals (Sweden)

Ming Li

2013-01-01

Full Text Available Delay analysis plays a role in real-time systems in computer communication networks. This paper gives our results in the aspect of delay analysis of fractal traffic passing through servers. There are three contributions presented in this paper. First, we will explain the reasons why conventional theory of queuing systems ceases in the general sense when arrival traffic is fractal. Then, we will propose a concise method of delay computation for hard real-time systems as shown in this paper. Finally, the delay computation of fractal traffic passing through severs is presented.

Active Control of Long Bridges Using Flaps

DEFF Research Database (Denmark)

Hansen, H. I.; Thoft-Christensen, Palle

The main problem in designing ultra-long span suspension bridges is flutter. A solution to this problem might be to introduce an active flap control system to increase the flutter wind velocity. The investigated flap control system consists of flaps integrated in the bridge girder so each flap...... is the streamlined part of the edge of the girder. Additional aerodynamic derivatives are shown for the flaps and it is shown how methods already developed can be used to estimate the flutter wind velocity for a bridge section with flaps. As an example, the flutter wind velocity is calculated for different flap...... configurations for a bridge section model by using aerodynamic derivatives for a flat plate. The example shows that different flap configurations can either increase or decrease the flutter wind velocity. for optimal flap configurations flutter will not occur....

Active aerodynamic stabilisation of long suspension bridges

DEFF Research Database (Denmark)

Nissen, Henrik Ditlev; Sørensen, Paul Haase; Jannerup, Ole Erik

2004-01-01

The paper describes the addition of actively controlled appendages (flaps) attached along the length of the bridge deck to dampen wind-induced oscillations in long suppension bridges. A novel approach using control systems methods for the analysis of dynamic stability is presented. In order to make...... use of control analysis and design techniques, a linear model of the structural and aerodynamic motion around equilibriun is developed. The model is validated through comparison with finite element calculations and wind tunnel experimental data on the Great Belt East Bridge in Denmark. The developed...... active control scheme is local in that the flap control signal at a given longitudinal position along the bridge only depends on local motion measurements. The analysis makes use of the Nyquist stability criteria and an anlysis of the sensitivity function for stability analysis. The analysis shows...

Polymeric salt bridges for conducting electric current in microfluidic devices

Science.gov (United States)

Shepodd, Timothy J [Livermore, CA; Tichenor, Mark S [San Diego, CA; Artau, Alexander [Humacao, PR

2009-11-17

A "cast-in-place" monolithic microporous polymer salt bridge for conducting electrical current in microfluidic devices, and methods for manufacture thereof is disclosed. Polymeric salt bridges are formed in place in capillaries or microchannels. Formulations are prepared with monomer, suitable cross-linkers, solvent, and a thermal or radiation responsive initiator. The formulation is placed in a desired location and then suitable radiation such as UV light is used to polymerize the salt bridge within a desired structural location. Embodiments are provided wherein the polymeric salt bridges have sufficient porosity to allow ionic migration without bulk flow of solvents therethrough. The salt bridges form barriers that seal against fluid pressures in excess of 5000 pounds per square inch. The salt bridges can be formulated for carriage of suitable amperage at a desired voltage, and thus microfluidic devices using such salt bridges can be specifically constructed to meet selected analytical requirements.