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排序方式: 共有244条查询结果,搜索用时 93 毫秒
31.
Telecommunications in the US is undergoing a revolution. Corporations are attempting to leverage their competencies in the deregulated environment in order to enhance their competitive position. While the eventual results of this flurry of partnerships that has recently occurred are uncertain, there are certain trends that are becoming increasingly apparent. This paper represents an essay on the telecommunications industry (or its converging associated industries) and describes its history and evolving structure. Fifty-four partnerships are examined in an attempt to systematically examine an industry in transition. Key implications of these partnerships are also discussed. 相似文献
32.
33.
Silicon - This paper examines a Junctionless quadruple gate (JLQG) MOSFET for analog and linearity distortion performance by numerically calculating transconductance and its higher order... 相似文献
34.
Sankalp Kota Louisiane Verger Varun Natu Maxim Sokol Michel W. Barsoum 《Journal of the American Ceramic Society》2021,104(2):733-739
The thermal stability and decomposition mechanisms of Fe2AlB2 powders, synthesized by reactive powder metallurgy, were studied under nitrogen (N2) or argon (Ar) atmospheres. The effects of using different FeB precursors to synthesize the Fe2AlB2 and hydrochloric acid (HCl) purification treatments on the thermal stability were also investigated. When as-synthesized Fe2AlB2 powders are treated in dilute HCl to dissolve impurity phases, decomposition in N2 atmospheres occurs readily above 1200 K. The decomposition reaction involves β-FeB precipitation and the liberated Al atoms reacting with the ambient N2 to form AlN. Under Ar environments, HCl-treated Fe2AlB2 powders decompose and precipitate β-FeB, by the out-diffusion of Al from the nanolaminated structure. Interestingly, isothermal annealing under N2 atmospheres revealed that Fe2AlB2 was more thermally stable when synthesized from lab-synthesized, instead of commercially available, FeB precursors and when the HCl treatment was avoided. The effects of the various factors on the decomposition temperature and decomposition mechanisms are discussed herein. 相似文献
35.
Clean Technologies and Environmental Policy - A large-scale mixed-integer linear programming model is developed for the supply chain and processing of agricultural residue to produce ethanol. The... 相似文献
36.
This study aims to examine the practicality of a novel passive heat transport system “thermosyphon heat transport device” (THTD). It is a fluid-filled unit, with both source and sink amalgamated within it. A vertical tube-in-tube design has been incorporated, consisting of heat source, adiabatic height, and sink. To showcase the performance, a transient numerical analysis is performed using ANSYS Fluent, which is compared with the simple closed thermosiphon (SCT) for heat transport capability (1 kW) and different adiabatic heights (0.25, 1, and 1.5 m). Also, the influence of axial conduction is examined. The proposed Therminol VP1-based THTD has better heat transport capability over SCT due to a uniform flow pattern. Although the time response diminishes with adiabatic height, the novelty is justified as the heat gained by THTD (adiabatic height: 1.5 m) is 1.5 times more than SCT. Furthermore, the THTD performance is experimentally analyzed by varying the coolant flow rate (0.01, 0.02, and 0.03 kg/s), heat load (100−600 W), and transport distance (0.25 and 0.75 m), which yielded 80%−90% energy efficiency. As the THTD is crucial for a conceptual solar indoor cooker, the response under transient heating/cooling conditions is also investigated, which depicted 300 s for transient heating and 10−50 s for transient cooling. 相似文献
37.
K. Ramesh Varun Joshi 《International Journal for Computational Methods in Engineering Science and Mechanics》2019,20(1):1-13
In the present article, the numerical solutions for three fundamental unsteady flows (namely Couette, Poiseuille, and generalized Couette flows) of an incompressible magnetohydrodynamic Jeffrey fluid between two parallel plates through a porous medium are presented using differential quadrature method. The equations governing the flow of Jeffrey fluid are modeled in Cartesian coordinate system. The resulting non-dimensional differential equations are approximated by using a new scheme that is trigonometric B-spline differential quadrature method. The scheme is based on the differential quadrature method in which the weighting coefficients are obtained by using trigonometric B-splines as a set of basis functions. This scheme reduces the equation into the system of first-order ordinary differential equation which is solved by adopting strong stability-preserving time-stepping Runge–Kutta scheme. The effects of the sundry parameters of interest on the velocity profiles are studied and the results are presented through graphs. It is observed that, the velocity increases from the horizontal channel to vertical channel. The velocity is a decreasing function of magnetic parameter. With an increase in time, the velocity increases. 相似文献
38.
High Open‐Circuit Voltages in Tin‐Rich Low‐Bandgap Perovskite‐Based Planar Heterojunction Photovoltaics
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39.
Das Apurba Rabha Susmita Saxena Varun Bhardwaj Aman Pandey Lalit M. Emmanuel K. A. Dobbidi Pamu 《Journal of Materials Science》2022,57(28):13586-13602
Journal of Materials Science - The exploration of exquisite electrical properties of biomaterials for clinical applications is driven by natural design. Inspired by the idea, composite thin films... 相似文献
40.
Shukla Varun Chaturvedi Atul Srivastava Neelam 《Wireless Personal Communications》2020,110(2):861-872
Wireless Personal Communications - Secure data communication is the need of hour today specifically when the wireless communication channel is insecure. We are proposing a protocol which can be... 相似文献