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41.
Rajeev Kumar Ranjan Kaushik Mazumdar Ratnadeep Pal Satish Chandra 《Analog Integrated Circuits and Signal Processing》2017,92(1):15-27
This paper presents a self-generating square/triangular wave generator using only the CMOS Operational Transconductance Amplifiers (OTAs) and a grounded capacitor. The output frequency and amplitude of the proposed circuit can be independently and electronically adjusted. The proposed circuit validates its advantage by consuming less amount of power, which is about 71.3 µW. The theoretical aspects are authentically showcased using the PSPICE simulation results. The performance of the proposed circuit is also verified through pre layout and post layout simulation results using the 90 nm GPDK CMOS parameters. A prototype of this circuit has been made using commercially available IC CA3080 for experimental verification. Experimentation also gives the similar output as per the theoretical proposition. The designed circuit is also made applicable to perform pulse width modulation (PWM). 相似文献
42.
Das Satish K. Nanda Umakanta Biswal Sudhansu M. Pandey Chandan Kumar Giri Lalat Indu 《SILICON》2022,14(6):2965-2973
Silicon - Short channel effects (SCEs) along with mobility degradation has a great impact on CMOS technology below 100 nm. These effects can be overcome by using gate and channel... 相似文献
43.
This work experimentally investigates Cr(VI) reduction to Cr(III) using waste scrap iron in the form of zerovalent iron (ZVI) collected from the mechanical workshop of the Institute, both in batch and continuous operation. The reduction of Cr(VI) to Cr(III) was found to be complete (~100%) depending on the experimental conditions. Lower pH values favour Cr(VI) reduction. Two concurrent reactions take place, that is reduction of Cr(VI) by Fe0 (ZVI) and by Fe2+ generated due to H+ corrosion of iron. Maximum around 22%, 11% and 2% Cr(III) remained dissolved in solution while the experiments were carried out at initial pH of 2, 4.67 and 7. Higher ZVI loading increases Cr(VI) reduction rate, however, consumption of iron is noted to be higher. The results indicate that the bed is exhausted rapidly at higher pH, initial Cr(VI) concentration and flow rate. This is attributable to predominance passivation of ZVI surface forming Cr(III)–Fe(III)‐oxide layer. SEM analysis of ZVI before and after the experiments confirms formation of passive oxide on iron surface is responsible for deterioration of Cr(VI) reduction efficiency due to its blanketing effect. 相似文献
44.
45.
Kouststaal Wilma; Reddy Chandan; Jackson Eric M.; Prince Steve; Cendan Daniel L.; Schacter Daniel L. 《Canadian Metallurgical Quarterly》2003,29(4):499
Older adults often demonstrate higher levels of false recognition than do younger adults. However, in experiments using novel shapes without preexisting semantic representations, this age-related elevation in false recognition was found to be greatly attenuated. Two experiments tested a semantic categorization account of these findings, examining whether older adults show especially heightened false recognition if the stimuli have preexisting semantic representations, such that semantic category information attenuates or truncates the encoding or retrieval of item-specific perceptual information. In Experiment 1, ambiguous shapes were presented with or without disambiguating semantic labels. Older adults showed higher false recognition when labels were present but not when labels were never presented. In Experiment 2, older adults showed higher false recognition for concrete but not abstract objects. The semantic categorization account was supported. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Suman Maiti Chandan Chakraborty Sabyasachi Sengupta 《Simulation Modelling Practice and Theory》2009,17(4):585-596
This paper presents a speed estimation technique for the permanent magnet synchronous motor drive. A Model Reference Adaptive System (MRAS) has been formed using the instantaneous and steady-state reactive powers to estimate the speed. It has been shown that such unique MRAS offers several desirable features. The proposed technique is completely independent of stator resistance and is less parameter sensitive, as the estimation-algorithm is only dependent on q-axis stator inductance. Also, the method requires less computational effort as the simplified expressions are used in the MRAS. The stability of the proposed system is achieved through Popov’s Hyperstability criteria. Extensive simulation results are presented to validate the proposed technique. The system is tested at different speeds including zero speed and a very satisfactory performance has been achieved. 相似文献
47.
P. Sandeep S. Chandan A. K. Chaturvedi 《Wireless Communications, IEEE Transactions on》2007,6(2):473-477
Using the approximate Fourier series technique we obtain expressions for the probability of error for bandlimited BPSK signalling in the presence of timing errors and fading. The derived results can be used to compute the error probabilities to any desired accuracy for Nakagami-m and Weibull fading channels. The effect of timing error on the performance of the raised cosine pulse has been evaluated for several fading parameters. We also compare the performance of some useful Nyquist pulses known 相似文献
48.
49.
Dipak Mazumdar Guler Yamanoglu Ramani Shankarnarayanan Roderick I. L. Guthrie 《国际钢铁研究》1995,66(1):14-19
To assess and quantify the relative importance of Reynolds and Froude numbers in reduced scale model studies (these cannot be simultaneously respected when the scale factor is less than unity), aqueous model investigations were carried out on three different laboratory scale tundish models. The experimental tundish systems included two strand, five strand skewed delta shaped and six strand rectangular shaped vessels. Experimental observations show that the depth of liquid in the model would only correspond to that in the full scale system, provided the model flow rate is scaled in accordance with the relationship: Qm = λ5/2 Qf.S, in which, A is the geometrical scaling factor. Furthermore, on the basis of residence time distribution measurements in two different configurations of the five strand tundish, it was demonstrated explicitly that flow phenomena in tundish systems are largely dominated by inertial forces and are therefore, essentially Froude dominated. 相似文献
50.
Recognizing the fact that the effective driving force (ΔK
eff) determines the fatigue crack propagation (FCP) rate and that the shear strain, which is considered to develop due to an
occurrence of crack closure, primarily contributes to the plastic deformation, an effort is made here to elucidate the role
of plastic deformation in FCP by developing a correlation between the ΔK
eff and the applied driving force (ΔK) with shear strain as variable. The effect of the degree of plastic deformation (i.e. shear strain level) on the FCP rates
at higher values of ΔK, where ΔK
eff approaches ΔK, approaching the Paris regime, appears minimal. On the other hand, the disparity between ΔK
eff and ΔK, which apparently increases with shear strain level, persists at lower values of ΔK. This suggests a strong influence of the degree of localized deformation on the FCP rates in the near threshold level. Hence,
an improvement of FCP rates in the near threshold level should follow an effort that promotes the plastic deformation near
the crack tip to a greater degree. This approach could, therefore, form the basis to explain the effect of the grain size,
microstructure, environment,R-ratio and crack size on the near-threshold FCP rates. 相似文献