5,628 research outputs found

    Evaluation of Local & Global Ductility Relationships for Low-Rise Masonry-Infilled Reinforced Concrete Frame Structures

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    The paper presents the findings on a parametric study of the period lengthening effects of low-rise masonryinfilled reinforced concrete frame buildings using an incremental dynamic analysis (IDA). Simplified 2D building models utilizing Bouc-Wen model for describing strength, stiffness degradation and pinching effect were subjected to some selected ground motion records ranging from far to near field earthquakes in low to high seismicity regions. Simple equations correlating local to global ductilities derived from pushover (PO) analysis for buildings under soft storey failure mechanism are proposed. The equations take into account the governing factors like critical interstorey drift and number of storeys. The applicability of the equations was verified up to 7-storey buildings from the results of IDA. Such simple ductility relationships are likely to facilitate mostly the coefficient-based method, in which the typical PO analysis may be bypassed and allows making intuitive insight into the seismic performance of buildings.published_or_final_versio

    Tuning Surface Morphology of Fluorescent Hydrogels Using a Vortex Fluidic Device.

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    In recent decades, microfluidic techniques have been extensively used to advance hydrogel design and control the architectural features on the micro- and nanoscale. The major challenges with the microfluidic approach are clogging and limited architectural features: notably, the creation of the sphere, core-shell, and fibers. Implementation of batch production is almost impossible with the relatively lengthy time of production, which is another disadvantage. This minireview aims to introduce a new microfluidic platform, a vortex fluidic device (VFD), for one-step fabrication of hydrogels with different architectural features and properties. The application of a VFD in the fabrication of physically crosslinked hydrogels with different surface morphologies, the creation of fluorescent hydrogels with excellent photostability and fluorescence properties, and tuning of the structure-property relationship in hydrogels are discussed. We conceive, on the basis of this minireview, that future studies will provide new opportunities to develop hydrogel nanocomposites with superior properties for different biomedical and engineering applications

    Electron irradiation effects in electrostrictive P(VDF-TrFE) copolymers

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    2000-2001 > Academic research: refereed > Refereed conference paperVersion of RecordPublishe

    Effect of electron irradiation on poly(vinylidene fluoride-trifluoroethylene) copolymers

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    2000-2001 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

    Electron acceleration associated with the magnetic flux pileup regions in the near-Earth plasma sheet: A multicase study

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    Using the Time History of Events and Macroscale Interactions during Substorms (THEMIS) observations, we study electron acceleration (<30 keV) in the magnetic flux pileup regions (FPRs) in the near-Earth plasma sheet (X ~ –10 RE). We present three cases of FRPs associated with dipolarization fronts and substorm dipolarization. Based on the characteristics of the magnetic field, we defined the magnetic field enhancement region (MFER) as the magnetic field with significant ramp that is usually observed near the dipolarization front boundary layer. On the other side, the increased magnetic field without a significant ramp is the rest of a FPR. Our results show that betatron acceleration dominates for 10–30 keV electrons inside the MFER, whereas Fermi acceleration dominates for 10–30 keV electrons inside the rest of the FPR. Betatron acceleration is caused by the enhancement of the local magnetic field, whereas Fermi acceleration is related to the shrinking length of magnetic field line. These accelerated electrons inside the FPRs in the near-Earth tail play a potentially important role in the evolution of the Earth's electron radiation belt and substorms

    Sensing characteristics of a novel NH 3-nitrided schottky-diode hydrogen sensor

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    A novel NHi-nitrided Schottky-diode hydrogen sensor has been successfully fabricated Measurements have been performed to investigate the sensitivity, stability and response speed of the sensor at different temperatures and hydrogen concentrations. It can respond to hydrogen variation very quickly and can give significant response ewn at low hydrogen concentration. The studied device exhibits high sensitivity of 350 % at 300 °C when 800 ppm IJ in N2 gas is introduced. The sensitivity is 15 times greater than that of the Pt-SiC sensor. The excellent hydrogen-sensing characteristics of this novel sensor make it very suitable for detecting hydrogen leakage in high-temperature environment. The effects of hydrogen adsorption on the barrier height and hydrogen reaction kinetics are also investigated. ©2004 IEEE.published_or_final_versio

    8-Chloroadenosine induces apoptosis in human coronary artery endothelial cells through the activation of the unfolded protein response

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    © 2019 The Authors Infiltration of leukocytes within the vessel at sites of inflammation and the subsequent generation of myeloperoxidase-derived oxidants, including hypochlorous acid, are key characteristics of atherosclerosis. Hypochlorous acid is a potent oxidant that reacts readily with most biological molecules, including DNA and RNA. This results in nucleic acid modification and the formation of different chlorinated products. These products have been used as biomarkers of inflammation, owing to their presence in elevated amounts in different inflammatory fluids and diseased tissue, including atherosclerotic lesions. However, it is not clear whether these materials are simply biomarkers, or could also play a role in the development of chronic inflammatory pathologies. In this study, we examined the reactivity of different chlorinated nucleosides with human coronary artery endothelial cells (HCAEC). Evidence was obtained for the incorporation of each chlorinated nucleoside into the cellular RNA or DNA. However, only 8-chloro-adenosine (8ClA) had a significant effect on the cell viability and metabolic activity. Exposure of HCAEC to 8ClA decreased glycolysis, and resulted in a reduction in ATP, with a corresponding increase in the chlorinated analogue, 8Cl-ATP in the nucleotide pool. 8ClA also induced sustained endoplasmic reticulum stress within the HCAEC, which resulted in activation of the unfolded protein response, the altered expression of antioxidant genes and culminated in the release of calcium into the cytosol and cell death by apoptosis. Taken together, these data provide new insight into pathways by which myeloperoxidase activity and resultant hypochlorous acid generation could promote endothelial cell damage during chronic inflammation, which could be relevant to the progression of atherosclerosis

    VICTour 1.1: Introducing virtual learning environments and gamification

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    Game engines are one of the few solutions to providing a true virtual campus tour experience. In this paper, we explore the evolution of the virtual campus tour and thereby the current and future work of game technology within virtual touring. An investigation is conducted into the application of objective-based gamification and its ability to encourage exploration of a virtual world. We also examine virtual campus tours as an alternate form of taught content via virtual learning environments (VLEs). An investigation into the use of head mounted displays to improve immersion is also explored

    Towards context-aware ubiquitous transaction processing: a model and algorithm

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    Transaction management for mobile and ubiquitous computing aims at providing mobile users with reliable services in a transparent way anytime anywhere. To make such a vision a reality, transaction processing for the mobile and ubiquitous computing needs to adapt to the runtime environments dynamically. However, most existing mobile transaction models do not consider the context-based transaction management. In this paper, we propose a context-aware transaction model and context-driven coordination algorithms. They are built on an event-context-action mechanism, enabling the transaction processing to adapt well to dynamically changing transaction context. The simulation results have also demonstrated that our model and algorithms can significantly improve the successful commit ratio under unstable context conditions. © 2011 IEEE.published_or_final_versionThe 2011 IEEE International Conference on Communications (ICC), Kyoto, Japan, 5-9 June 2011. In IEEE International Conference on Communications, 2011, p. 1-

    Dynamic routing model and solution methods for fleet management with mobile technologies

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    Author name used in this publication: K. L. ChoyAuthor name used in this publication: Wenzhong Shi2007-2008 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe
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