Search results for "Bridge"
showing 10 items of 355 documents
Analytical compact modeling of GMR based current sensors: Application to power measurement at the IC level
2010
An analytical compact model for giant magnetoresistance (GMR) based current sensors has been developed. Different spin-valve based full Wheatstone bridge sensors, with the current straps integrated in the chip, have been considered. These devices have been experimentally characterized in order to extract the model parameters. In this respect, we have focused on the sensors linear operation regime. The model, which allows the individual description of the magnetoresistive elements, has been implemented in a circuit simulator by means of a behavioral description language: Verilog-A. We also propose the use of the devices in a direct power measurement application at the integrated circuit (IC)…
Active power analog front-end based on a Wheatstone-type magnetoresistive sensor
2011
Abstract In the proposed work a practical magnetoresistive wattmeter based on a commercial sensor is designed to measure active power at industrial frequencies. The electronic conditioning circuit uses differential blocks in order to preserve the sensor initial common mode rejection ratio. A 700 W power level has been reached with an uncertainty less than 1%. With few changes the proposed circuitry could be used in metering applications.
Evaluation of the Safety Performance of Turbo Roundabouts by Means of a Potential Accident Rate Mode
2015
Turbo roundabouts are a particular road intersection layout, designed to increase the safety of double-lane roundabouts, while maintaining their excellent capacity. The main feature of this new concept of roundabout is the impossibility to move from one lane to another, provided by physical barriers marking the lanes. The paper shows an application to turbo roundabouts of a potential accident rate model, aiming to evaluate their safety improvement. Themodel is based on the concept of potential conflict: each vehicle involved in a general intersection performs a series of maneuvers which potentially imply a crash, according to the actual traffic. The number of accidents related to each criti…
Durability evaluations on the bridge over the Ruwais lagoon at Jeddah
2008
The bridge over the Ruwais Lagoon at Jeddah, Saudi Arabia, has been built in the first half of 80s within a large-scale program project concerning the "corniche", a seafront boulevard running more than 30 Km from its northern to its southern end.
Effects of corrosion on a steel bowstring bridge in marine environment: A case-study of assessment and retrofit
2021
The case-study of a steel bowstring bridge set in a marine environment and highly damaged by corrosion is presented. The bridge was built in 2004 and was repainted for corrosion protection in 2010. Despite the recent construction and the maintenance interventions, many structural elements like hangers are highly damaged by corrosion with decreasing performance in terms of serviceability and ultimate limit states. A deep investigation was carried out in order to assess the bridge and to establish the necessary retrofit actions to be carried out in the near future. In-situ tests reveal the reduced performance of the original steel in terms of strength and corrosion protection, together with t…
Steel and composite tied-arch bridges: a conceptual approach to structural design
2021
The behaviour of tied-arch bridges with composite decks (bowstring bridges) is overly sensitive to the different choices made by the designer in the first phases of the conceptual approach, mainly in the design of the arch and the deck. The geometry of the arch shape, the design of the arch–tie joint and the construction sequence can significantly modify the global behaviour in terms of stress state and deformed configuration. After a general discussion on the different parameters affecting the behaviour of bowstring bridges with steel–concrete composite decks, the consequences of choices made in the conceptual design phases are discussed, analysing the effects of each choice on the global…
Simplified Procedure for Evaluating the Effects of Creep and Shrinkage on Prestressed Concrete Girder Bridges and the Application of European and Nor…
2013
The effects of time-dependent phenomena on concrete prestressed girder bridges are investigated. The study concerns the case of bridges built directly in their final configuration and that of bridges built by a sequence of stages in which geometry, restraints, and loads vary until the final configuration is achieved. An analytical approach based on the principles of aging linear viscoelasticity and the age-adjusted effective modulus method is followed. The paper has two aims: the first is to provide an efficient and simplified tool for the evaluation of the structural response in the early stages of design; the second is to compare the results of the analyses on actual cases of bridges when…
Polar organic marker compounds in PM2.5 aerosol from a mixed forest site in western Germany
2008
The molecular composition of PM2.5 (particulate matter with an aerodynamic diameter2.5 microm) aerosol samples collected during a very warm and dry 2003 summer period at a mixed forest site in Jülich, Germany, was determined by gas chromatography/mass spectrometry in an effort to evaluate photooxidation products of biogenic volatile organic compounds (BVOCs) and other markers for aerosol source characterization. Six major classes of compounds represented by twenty-four individual organic species were identified and measured, comprising tracers for biomass combustion, short-chain acids, fatty acids, sugars/sugar alcohols, and tracers for the photooxidation of isoprene and alpha-/beta-pinene.…
Users’ Preferences for Designing Spaces under Urban Bridges as Vital Urban Spaces
2018
Today’s fast-paced urbanization process has caused many problems in urban development. Therefore, urban space is slowly losing its nature and disappearing due to the speed of rapid urban development. Trying to keep up with the modern era’s prevalent epoch of roads and bridges, urban policies in Iran have focused on developing road networks in recent years. Thus numerous elevated structures, urban highways and bridges are used to connect the urban fabric of the country’s cities, enabling the smooth transition of traffic in its cities. Although many view urban highways merely as tools for mobility; it is true that they influence on urban structure and the communities that they interconnect. H…
Bridges Baltimore 2015: Charmed by Mathematics in Charm City
2016
In 2015, the Bridges World Conference, the most significant annual international gathering to be held for exploring connections between mathematics and the arts, met in Baltimore, USA. The conference program included lectures by recognized scholars and artists, the world largest exhibition of mathematical art, thematic theatre performances, a poetry afternoon demonstrating how mathematics can interrelate with literature, and a short film festival as well as workshops organized by researchers, educators and artists. nonPeerReviewed