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The understanding of the flow characteristics and effect of gas-solid interactions in pneumatic risers is fundamental to investigate to ensure effective design cost-effective operation. Thus, to understand the effect of gas-solid interactions on the hydrodynamics of newly proposed conversing risers, this study mainly focused on predicting pressure drop in the dilute phase pneumatic conveying system. The experiments were conducted in a converging riser having a convergence angle of 0.2693°. Various solid particles such as sago, black mustard, and alumina have been considered to study the effect of particle sizes and density on the pressure drop. The experimental outcomes indicate that the total pressure drop increases with an increase in the solid density and gas mass flow rate. Moreover, smaller particle sizes are also increased the pressure drop. An empirical correlation is developed for the prediction of total pressure drop ΔPT in converging pneumatic riser via dimensional analysis. All dependent variables such as particle and air density, drag force, acceleration due to gravity, the mass flow rate of air and particle, the diameter of particle and converging riser, the height of converging riser were considered to develop the empirical correlation. The established relationship is tested, and experimental data have been fitted for its validation. The estimated relative error of less than 0.05 proved the significance of the developed correlation. Hence, it can be stated that the established relationship is useful in studying the effects of various parameters on the pressure drop across the length of the conversing riser.  相似文献   
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Wireless Personal Communications - The paper reports the performance of an energy harvesting cognitive radio network under primary user emulation (PUE) attack. A secondary user (SU) can harvest...  相似文献   
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ZnO rice like nonarchitects are grafted on the graphene carbon core via a rapid microwave synthesis route. The prepared grafted systems are characterized via XRD, SEM, RAMAN, and XPS to examined the structural and morphological parameters. Zinc oxide grafted graphene sheets (ZnO-G) are further doped in β-phase of polyvinylidene fluoride (PVDF) to prepare the polymer nanocomposites (PNCs) via mixed solvent approach (THF/DMF). β-phase confirmation of PVDF PNCs is done by FTIR studies. It is observed that ZnO-G filler enhances the β-phase content in the PNCs. Non-doped PVDF and PNCs are further studied for rheological behavior under the shear rate of 1–100 s−1. Doping of ZnO-G dopant to the PVDF matrix changes its discontinuous shear thickening (DST) behavior to continues shear thickening behavior (CST). Hydrocluster formation and their interaction with the dopant could be the reason for this striking DST to CST behavioral change. Strain amplitude sweep (10−3% -10%) oscillatory test reveals that the PNCs shows extended linear viscoelastic region with high elastic modulus and lower viscous modulus. Effective shear thickening behavior and strong elastic strength of these PNCs present their candidature for various fields including mechanical and soft body armor applications.  相似文献   
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Electrospinning (ES) is a most reliable method for synthesizing one dimensional (1D) fibrous material. Fibrous materials are having peculiar interest owing to their fascinating properties. For efficient hydrogen fuel generation, electrocatalytic water splitting is one of the finest way of producing hydrogen in a pure form. But it is encountered by the counter oxygen evolution reaction (OER) in more often. As of now, noble metal based catalysts are utilized in the commercial sector. Some of the disadvantages associated with the noble materials are restrict their usage commercially. To address this issue, herein, we have synthesized One dimensional (1D), hydrated porous cobalt phosphate fibrous network by an ES method and act as an electrocatalyst for OER in both alkaline and neutral media for the first time, which exhibits an overpotential of 245 and 457 mV respectively at a current density of 10 mAcm?2 with astonishing stability.  相似文献   
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Multimedia Tools and Applications - Performance of computerized diagnostic systems yearning to be approved by medical regulatory bodies must meet the expectations of human experts. Highly accurate...  相似文献   
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The proposed system portrays the application space examination of a diverse cryptosystem processor with dynamic reconfiguration abilities. It is appropriate to a variety of signal processing application domains namely telecommunications, image processing, video coding and cryptographic processing. To differentiate between application spaces of the processor, the performance is correlated with cutting edge devices, taking ability to program, energy efficiency and computational potential as the important factors. In general the conventional method of computation is processed by means of Virtual Secure Circuit (VSC) on Advanced Encryption Standard (AES) and performance of the device Field Programmable Gate Array (FPGA) after implementation is analyzed in terms of delay and throughput. In the conventional method area overhead and power consumption are less where as the architecture lags in performance and throughput. It has been overcome through the fully parallel pipelined Architecture of the VSC on AES which outperforms the existing method in terms of performance and throughput. The energy efficiency and performance are considerably more important than processor that are used for general purpose, while still preserving a Convenient approach of programming that mainly bank on software oriented languages. The exploit of VSC based AES is to formulate the cryptographic processor held against Side Channel Attacks like attacks based on power supply and electromagnetic signals. Then the experimental result shows the promising outcomes when compared to previous methods.

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