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排序方式: 共有1448条查询结果,搜索用时 15 毫秒
1.
Kotteda V. M. Krushnarao Schiaffino Arturo Chattopadhyay Ashesh Shantha-Kumar Sanjay Kumar Vinod Bronson Arturo 《Metallurgical and Materials Transactions B》2019,50(4):1559-1565
Metallurgical and Materials Transactions B - The effect of the surface tension–viscosity dissipation driving liquid Ti flow into a B4C packed bed was analyzed at 1941 K and 2573 K. The model... 相似文献
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This article presents a design methodology for linearizing GaN HEMT amplifiers based on splitting a large FET into multiple parallel FETs with same total gate periphery and by biasing them individually. By varying the biases, the magnitude and the phase of the IMD3 components at the output of FET changes. A detailed simulation methodology using commercial microwave CAD software is presented. Simulation results show that by biasing one device in Class AB and other(s) in deep Class AB mode, IMD3 components of parallel FETs can be made out of phase to each other leading to cancellation and improvement in linearity. Three prototype circuits were simulated using (a) a single 5 mm FET (1 × 5 mm), (b) two parallel 2.5 mm FETs (2 × 2.5 mm), and (c) four parallel 1.25 mm FETs (4 × 1.25 mm), for a total gate periphery of 5 mm, over the frequency range of 0.8 to 1.0 GHz. IMD3 improvement up to 20 dBc was achieved with the 4 × 1.25 mm circuit when the FET biases were optimized. Measurement results show improvement in linearity up to 20 dBc for 4 × 1.25 mm circuit. The proposed method improves linearity without a substantial penalty on the power consumption and is straightforward to implement. 相似文献
3.
Soumya Ghosh Chowdhury Jagannath Chanda Sreedip Ghosh Koushik Banerjee Shib Shankar Banerjee Amit Das Prasenjit Ghosh Sanjay Kr. Bhattacharyya Rabindra Mukhopadhyay 《Polymer Engineering and Science》2020,60(8):1973-1983
Proficiency on underlying mechanism of rubber-metal adhesion has been increased significantly in the last few decades. Researchers have investigated the effect of various ingredients, such as hexamethoxymethyl melamine, resorcinol, cobalt stearate, and silica, on rubber-metal interface. The role of each ingredient on rubber-metal interfacial adhesion is still a subject of scrutiny. In this article, a typical belt skim compound of truck radial tire is selected and the effect of each adhesive ingredient on adhesion strength is explored. Out of these ingredients, the effect of cobalt stearate is found noteworthy. It has improved adhesion strength by 12% (without aging) and by 11% (humid-aged), respectively, over control compound. For detailed understanding of the effect of cobalt stearate on adhesion, scanning electron microscopy and energy dispersive spectroscopy are utilized to ascertain the rubber coverage and distribution of elements. X-ray photoelectron spectroscopy results helped us to understand the impact of CuXS layer depth on rubber-metal adhesion. The depth profile of the CuXS layer was found to be one of the dominant factors of rubber-metal adhesion retention. Thus, this study has made an attempt to find the impact of different adhesive ingredients on the formation of CuXS layer depth at rubber-metal interface and establish a correlation with adhesion strength simultaneously. 相似文献
4.
Anton Polotai Julie Voak Jim Henry David Thoss Yi Yang Sanjay Chitale 《International Journal of Applied Ceramic Technology》2020,17(2):728-733
The need for electronics to operate at temperatures of 200°C and above continues to grow. These applications include avionics, aerospace, automotive, downhole drilling, mining, and many others. To satisfy this demand, a significant amount of research and development has been conducted. Despite the efforts, the number of new electronic components designed specifically for high-temperature operation is still relatively limited. In Low Temperature Co-fired Ceramic (LTCC) packages, LTCC materials are generally used as the host media for a number of pre-fabricated semiconductor components. As a result, reliability of the entire LTCC package largely depends on the performance of the least robust component. Ferro A6M-E and Ferro L8 are the two well-established and recognized LTCC dielectrics widely used for mid and high frequency LTCC applications, including several high reliability aerospace and defense applications that require demanding Mil-Spec qualifications. This study is our first attempt to characterize and understand basic high-temperature dielectric properties of these two commercial LTCC materials. The secondary objective is to initiate a dialogue in attempt to establish reliability requirements for LTCC packages dedicated for high-temperature operation. 相似文献
5.
Ajay Jaryal Suresh Thakur Joginder Singh Pathania Sanjay Vikrant Dinesh Kumar Lokesh Verma 《Hemodialysis international. International Symposium on Home Hemodialysis》2020,24(1):E10-E12
Neurological complications are common in patients with acute or chronic renal failure, especially when there is marked reduction in the glomerular filtration rate (GFR). One such clinical syndrome, uremic encephalopathy (UE), occurs due to widespread dysfunction of central nervous system (CNS). It manifests with myriad clinical features and usually is suggested by bedside elicitation of asterixis (flapping tremor). Symptomatic involvement of the basal ganglia manifesting as choreoathetosis and clinical and radiological resolution with hemodialysis has been reported in the medical literature, but only rarely. The present report details such a case. 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
9.
Wireless Personal Communications - Femtocell deployment is an important strategy when it comes to improvement of QoS metrics in areas of poor cell coverage like indoors in an LTE environment. This,... 相似文献
10.
Scientometrics - This study investigates a potential relationship between highly-cited scholarly papers and the number of citations received by other papers with which they share a journal issue.... 相似文献