17 research outputs found

    Stability of Intensity Ratio of Line Pairs

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    Robotic Platform Rabit for Condition Assessment of Concrete Bridge Decks Using Multiple NDE Technologies

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    Current assessment of concrete bridge decks relies on visual inspection and use of simple nondestructive and destructive evaluations. More advanced, but still manual nondestructive evaluation (NDE) technologies provide more comprehensive assessment. Still, due to a lower speed of data collection and still not automated data analysis and interpretation, they are not used on a regular basis. The development and implementation of a fully autonomous robotic system for condition assessment of concrete bridge decks using multiple nondestructive evaluation (NDE) technologies is described. The system named RABIT (Robotics Assisted Bridge Inspection Tool) resolves issues related to the speed of data collection and analysis. The system concentrates on the characterization of internal deterioration and damage, in particular three most common deterioration types in concrete bridge decks: rebar corrosion, delamination, and concrete degradation. For those purposes, RABIT implements four NDE technologies: electrical resistivity (ER), impact echo (IE), ultrasonic surface waves (USW) and ground-penetrating radar (GPR). Because the system utilizes multiple probes or large sensor arrays for the four NDE technologies, the spatial resolution of the results is significantly improved. The technologies are used in a complementary way to enhance the overall condition assessment and certainty regarding the detected deterioration. In addition, the system utilizes three high resolution cameras to image the surface of the deck for crack mapping and documentation of previous repairs, and to image larger areas of the bridge for inventory purposes. Finally, the robot’s data visualization platform facilitates an intuitive 3-dimensional presentation of the main three deterioration types and deck surface features

    1989 as a mimetic revolution: Russia and the challenge of post-communism

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    Various terms have been used to describe the momentous events of 1989, including Jürgen Habermas’s ‘rectifying revolution,’ and my own notion of 1989 as a type of ‘anti-revolution’: repudiating not only what had come before, but also denying the political logic of communist power, as well as the emancipatory potential of revolutionary socialism in its entirety. In the event, while the negative agenda of 1989 has been fulfilled, it failed in the end to transcend the political logic of the systems that collapsed at that time. This paper explores the unfulfilled potential of 1989. Finally, 1989 became more of a counter- rather than an anti-revolution, replicating in an inverted form the practices of the mature state socialist regimes. The paucity of institutional and intellectual innovation arising from 1989 is striking. The dominant motif was ‘returnism,’ the attempt to join an established enterprise rather than transforming it. Thus, 1989 can be seen as mimetic revolution, in the sense that it emulated systems that were not organically developed in the societies in which they were implanted. For Eastern Europe ‘returning’ to Europe appeared natural, but for Russia the civilizational challenge of post-communism was of an entirely different order. There could be no return, and instead of a linear transition outlined by the classic transitological literature, Russia’s post-communism demonstrated that the history of others could not be mechanically transplanted from one society to another

    ABSTRACT A Continuous Folding Process for Sheet Materials

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    In this paper, we present a new and innovative sheet material folding technology and the associated advances in folding different patterns using continuous manufacturing techniques. A novel approach is developed for the continuous folding process where sheet material is progressively folded in two dimensions, through a set of rollers, followed by a configured roller for the final folding in the third dimension. The final roller can be designed for longitudinal folding, cross-folding and angular folding to produce the desired folded pattern. This process is more economical than traditional forming processes. An application of this process to the production of impact energy absorption structure is presented

    The Matrix Effect Upon both Arc Temperature and Electron Pressure

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    Nanotechnology Role for the Production of Clean Fuel E-85 and Petrochemical Raw Materials

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    There have been a number of substantive technical changes that can be described as revolutionary process and evolutionary process. One of these approaches is the use of nanotechnology in the two-stage pyrolysis of petroleum residues of the heavy distillates separated from the Arabian crude oil. Two-stage catalytic pyrolysis technique proved to be an excellent method for the production of unsaturated hydrocarbons (which easily can be converted to alcohol, by addition of H2O, for the production of E-85, i.e., clean fuel) regardless the type of feed stocks used. Basically, the catalysts are arranged into three large groups; amorphous and crystalline alumino-silicates, alkaline or alkaline earth alumino compounds, and different metal oxides on different catalyst carriers such as Zeolites. The high yield of ethylene (30–40%) brought by different catalysts at temperatures of 700–750°C appear to justify the intensive research work in this field
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