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1.
Wireless Personal Communications - Recently, the theory of effective rate has attracted much attention, since it can take the delay aspect into account when performing channel capacity analysis. In... 相似文献
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Journal of Materials Science - Phase separation is a relevant mode of transformation for microstructure development in multicomponent alloys. Its occurrence can drastically alter the composition... 相似文献
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Jain Amita Yadav Sudesh Vij Sonakshi Kumar Yogesh Tayal Devendra Kumar 《Wireless Personal Communications》2020,110(3):1303-1321
Wireless Personal Communications - Traffic network is basically a “network of networks” consisting of mainly two types of networks: road network and a travel network. Due to drastic... 相似文献
5.
Manika Chaudhary Milan Singh Ashwani Kumar Yogendra K. Gautam Anil K. Malik Yogesh Kumar Beer Pal Singh 《Ceramics International》2021,47(2):2094-2106
The current research work presents a facile and cost–effective co-precipitation method to prepare doped (Co & Fe) CuO and undoped CuO nanostructures without usage of any type of surfactant or capping agents. The structural analysis reveals monoclinic crystal structure of synthesized pure CuO and doped-CuO nanostructures. The effect of different morphologies on the performance of supercapacitors has been found in CV (cyclic voltammetry) and GCD (galvanic charge discharge) investigations. The specific capacitances have been obtained 156 (±5) Fg?1, 168(±5) Fg?1 and 186 (±5) Fg?1 for CuO, Co-doped CuO and Fe-doped CuO electrodes, respectively at scan rate of 5 mVs?1, while it is found to be 114 (±5) Fg?1, 136 (±5) Fg?1 and 170 (±5) Fg?1 for CuO, Co–CuO and Fe–CuO, respectively at 0.5 Ag-1 as calculated from the GCD. The super capacitive performance of the Fe–CuO nanorods is mainly attributed to the synergism that evolves between CuO and Fe metal ion. The Fe-doped CuO with its nanorods like morphology provides superior specific capacitance value and excellent cyclic stability among all studied nanostructured electrodes. Consequently, it motivates to the use of Fe-doped CuO nanostructures as electrode material in the next generation energy storage devices. 相似文献
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This work developed a computational methodology to evaluate and compare standard fire exposures such as those outlined in ASTM E119 with real fire exposures and determine the difference in the temperature rise of a rail car floor assembly. The real fire exposures simulated in this work were identified in a review of incidents and consisted of a constantly-fed diesel fuel spill, a localized trash fire, and a gasoline spill simulated from a collision of the railcar with an automobile. These realistic fire exposures were applied to a variety of exemplar rail cars representative of single-level and bi-level passenger cars. These floor assembly models exposed to realistic fires were simulated in Fire Dynamics Simulator (FDS). The thermal exposure at the underside of railcar provided by FDS was coupled with a thermal model in ABAQUS, which provided the evolution of temperature in different components of the floor assembly. The standard scenarios were simulated for 2 hours instead of the typical 30 minutes to identify the appropriate exposure duration in ASTM E119, which can better represent a real fire scenario. The average and maximum temperatures predicted at the unexposed surface for both scenarios were compared with the threshold values given in NFPA 130. 相似文献
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Multimedia Tools and Applications - In the way of communication, facial expression act as non-verbal communication and play an important role in social interaction by providing some contextual... 相似文献
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The graft copolymerization of methyl methacrylate onto natural rubber (NR) was carried out varying the concentration of monomer, initiator, thiourea, and silver nitrate over a wide range. The grafting reaction was temperature-dependent. From the Arrhenius plot, the overall energy of activation was computed. A suitable reaction scheme and rate expression for the rate of polymerization was suggested. 相似文献
10.
Kenneth D. Walsh Anil Sawhney Howard H. Bashford 《Canadian Metallurgical Quarterly》2007,133(3):254-261
The production equation called Little’s law has been applied to construction data recently. However, Little’s law was derived for steady-state conditions assuming constant input and output rates and long production runs. Production in construction is inherently temporary, and learning curves and environmental influences often render input and output rates unequal and nonlinear. Starting with a conservation of mass formulation, general equations for work-in-process and cycle time for unsteady-state conditions and limited run production are developed. The motivation behind these equations is to explain common trends in production variables seen on construction projects. Previous studies have shown that when output from a construction production system is drastically increased, a significant upward impact is also seen on cycle time and work-in-process, and this work provides underlying theory and equations to explain these trends. Cycle time and work-in-process equations are presented as functions of time and on average. Data from construction activities are used to show that unsteady-state conditions commonly occur. Reasonable simplifications of the general equations provide guidelines for buffer sizing and resource allocation decisions. 相似文献