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101.
In this work, the potential benefit of tri-metal gate engineered nanowire MOSFET with gate stack for analog/RF applications is developed and presented. A systematic, quantitative investigation of main figure of merit for the device is carried out to demonstrate its improved RF/analog performance. The results show an improvement in drain current, \(I_{\mathrm{on}} /I_{\mathrm{off}}\) ratio, transconductance, unity-gain frequency (\(f_{\mathrm{T}}\)), maximum oscillation frequency (\(f_{\mathrm{max}}\)) providing superior RF performance as compared to single and dual-metal gate stack nanowire MOSFET. The suitability of the device for analog/RF applications is also analyzed by implementing the device in a low-noise amplifier circuit, and the S-parameter values are estimated. 相似文献
102.
103.
Martensitic Phase Transformation and Deformation Behavior of Fe–Mn–C–Al Twinning‐Induced Plasticity Steel during High‐Pressure Torsion 下载免费PDF全文
104.
A Resistive Random Access Memory (RRAM), where the memory performance principally originated from ‘resistive’ change rather than ‘capacitive’ one (the case with conventional CMOS memory devices), has attracted researchers across the globe, owing to its unique features and advantages meeting the demands of future generation high-speed, ultra low power, nano dimensional memory devices. A large family of semiconducting oxides have been investigated as insulator for Resistive Random Access Memory (RRAM), amongst which TiO2 is one of the potential candidate, principally owing to some of its remarkable advantages e.g. wide band gap, high temperature stability and high dielectric constant with flexibility to offer both unipolar and bipolar switching, which are essential for RRAM device applications. In this review article, we tried to represent the long voyage of TiO2 based RRAM, towards the improvement of the reliability aspects of the device performance in a comprehensive manner. Starting with the key factors like oxygen vacancies, Ti interstitials and electroforming, which are responsible for resistive switching phenomenon, various material preparation techniques for RRAM development have been discussed with emphasis on relative merits and bottlenecks of the process. The factors like electrode material and geometry, device structuring, doping, compliance current, annealing effect etc., which play the pivotal role in determining the switching performance of the device, have been reviewed critically. Finally, the article concludes with the comparison of different TiO2 based RRAM devices followed by the prediction of possible future research trends. 相似文献
105.
Suvanjan Bhattacharyya Himadri Chattopadhyay Anindya Guin Ali Cemal Benim 《传热工程》2019,40(17-18):1451-1460
ABSTRACTIn the present study, the effect of forward inclined turbulators on the heat transfer enhancement in a duct is investigated, for forced convection. Turbulator configurations with three different pitch ratios and three different inclination angles are investigated for seven Reynolds numbers within the range 500–50,000. Investigations are performed experimentally as well as computationally, within a computational fluid dynamics framework. A distinguishing feature of the latter has been the employment of a turbulence model, the transitional shear stress transport model that is applicable throughout the presently considered range of Reynolds numbers containing laminar, transitional, and turbulent regions. At the beginning of the study, measurements and predictions are validated against analytical and empirical expressions known for a plain duct. The results obtained for turbulators configurations indicate that Nusselt number increases with the inclination angle but decreases with the pitch ratio. The influence of the inclination angle on the Nusselt number and thermal enhancement factor is found to be stronger than that of the pitch ratio. For all Reynolds numbers and for all configurations, the thermohydraulic performance is observed to increase, leading to thermal enhancement factors within the range 2–5. In all cases, a quite good agreement of the predictions and experiments is observed, which increases the confidence in the accuracy of both approaches. 相似文献
106.
Steady boundary layer slip flow and heat transfer over a flat porous plate embedded in a porous media 总被引:1,自引:0,他引:1
Krishnendu Bhattacharyya Swati Mukhopadhyay G.C. Layek 《Journal of Petroleum Science and Engineering》2011,78(2):304-309
A mathematical model is presented for analyzing the boundary layer forced convective flow and heat transfer of an incompressible fluid past a porous plate embedded in a Darcy porous medium. Velocity and thermal slips are considered instead of no-slip conditions at the boundary. The similarity solutions for the problem are obtained and the reduced nonlinear ordinary differential equations are solved numerically. In case of porous plate, fluid velocity increases whereas non-dimensional temperature decreases for increasing values of suction parameter but it increases with increasing blowing parameter. Our analysis reveals that the increase of velocity slip parameter reduces the momentum boundary layer thickness and also enhances the heat transfer from the plate. On the other hand, heat transfer decreases with thermal slip parameter. 相似文献
107.
Nimish Sane Hojin Kee Gunasekaran Seetharaman Shuvra S. Bhattacharyya 《Journal of Signal Processing Systems》2011,65(2):229-244
Tools for designing signal processing systems with their semantic foundation in dataflow modeling often use high-level graphical
user interfaces (GUIs) or text based languages that allow specifying applications as directed graphs. Such graphical representations
serve as an initial reference point for further analysis and optimizations that lead to platform-specific implementations.
For large-scale applications, the underlying graphs often consist of smaller substructures that repeat multiple times. To
enable more concise representation and direct analysis of such substructures in the context of high level DSP specification
languages and design tools, we develop the modeling concept of topological patterns, and propose ways for supporting this concept in a high-level language. We augment the dataflow interchange format (DIF)
language—a language for specifying DSP-oriented dataflow graphs—with constructs for supporting topological patterns, and we
show how topological patterns can be effective in various aspects of embedded signal processing design flows using specific
application examples. 相似文献
108.
Experimental investigation on the influence of electrochemical machining parameters on machining rate and accuracy in micromachining domain 总被引:3,自引:0,他引:3
B. Bhattacharyya J. Munda 《International Journal of Machine Tools and Manufacture》2003,43(13):1301-1310
Non-conventional machining is increasing in importance due to some of the specific advantages which can be exploited during micromachining operation. Electrochemical micromachining (EMM) appears to be a promising technique, since in many areas of application, it offers several special advantages that include higher machining rate, better precision and control, and a wider range of materials that can be machined. A better understanding of high rate anodic dissolution is urgently required for EMM to become a widely employed manufacturing process in the micro-manufacturing domain. An attempt has been made to develop an EMM experimental set-up for carrying out in depth research for achieving a satisfactory control of the EMM process parameters to meet the micromachining requirements. Keeping in view these requirements, sets of experiments have been carried out to investigate the influence of some of the predominant electrochemical process parameters such as machining voltage, electrolyte concentration, pulse on time and frequency of pulsed power supply on the material removal rate (MRR) and accuracy to fulfil the effective utilization of electrochemical machining system for micromachining. A machining voltage range of 6 to 10 V gives an appreciable amount of MRR at moderate accuracy. According to the present investigation, the most effective zone of pulse on time and electrolyte concentration can be considered as 10–15 ms and 15–20 g/l, respectively, which gives an appreciable amount of MRR as well as lesser overcut. From the SEM micrographs of the machined jobs, it may be observed that a lower value of electrolyte concentration with higher machining voltage and moderate value of pulse on time will produce a more accurate shape with less overcut at moderate MRR. Micro-sparks occurring during micromachining operation causes uncontrolled material removal which results in improper shape and low accuracy. The present experimental investigation and analysis fulfils various requirements of micromachining and the effective utilization of ECM in the micromachining domain will be further strengthened. 相似文献
109.
Influence of tool vibration on machining performance in electrochemical micro-machining of copper 总被引:5,自引:0,他引:5
B. Bhattacharyya M. Malapati J. Munda A. Sarkar 《International Journal of Machine Tools and Manufacture》2007,47(2):335-342
Electrochemical micro-machining (EMM) appears to be promising as a future micro-machining technique since in many areas of applications, it offers several advantages, including biomedical and MEMS applications. A suitable micro-tool vibration system has been developed, which consists of tool-holding unit, micro-tool vibrating unit, etc. The developed system was used successfully to control material removal rate (MRR) and machining accuracy to meet the micro-machining requirements. Micro-holes have been produced on thin copper workpiece by EMM with stainless-steel micro-tool. Experiments have been carried out to investigate the most effective values of process parameters such as micro-tool vibration frequency, amplitude and electrolyte concentration for producing micro-hole with high accuracy and appreciable amount of MRR. From the experimental results and SEM micrographs, it is evident that the introduction of micro-tool vibration improves EMM performance characteristics. Lower electrolyte concentration in the range of 15–20 g/l reduces stray current effects. Hertz (Hz) range of tool vibration frequency improves the removal of sludge and precipitates from very small interelectrode gap. The 150–200 Hz range of tool vibration frequency can be recommended for EMM, which provides a better electrochemical machining in the narrow end gap. Compared to kHz range, Hz range micro-tool's vibration improves the MRR and accuracy in EMM. 相似文献
110.
The authors point out a simple alternative proof of the main result (Theorem 1) of the paper by Barmish, Hollot, Kraus, and Tempo (1992). This proof follows immediately on applying the vertex result of Hollot and Yang (1990) to the generalization of Kharitonov's Theorem given by Chapellat and Bhattacharyya (1988, 1989). The authors also point out that more general vertex results are known 相似文献