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41.
Pandey Mamta Litoriya Ratnesh Pandey Prateek 《Wireless Personal Communications》2019,107(4):1687-1708
Wireless Personal Communications - Increased dominance of mobile applications (henceforth, app) over conventional software applications is quite apparent; however, there is a lack of structured... 相似文献
42.
Sanjeev Kumar Pandey S. L. Patil Praveen V. Pol S. B. Phadke 《International Journal of Electronics》2020,107(10):1682-1703
ABSTRACT In this paper, two control schemes for boost converters affected by uncertainties in input voltage and load are proposed. The boost converter dynamics is redefined in terms of new state variables to facilitate the use of a disturbance observer that can estimate matched and unmatched disturbances. A sliding surface, which is new in the context of boost converters, is proposed to enable tracking and regulation of output voltage without requiring measurement of input voltage and load current. The stability of the overall system including the disturbance observer, the sliding variable and the output is proved. The performance of the schemes is assessed for regulation of output voltage and tracking of reference voltage by simulation as well as experimentation in which various types of uncertainties and various types of reference voltages are considered. 相似文献
43.
44.
Jitendra Kumar Pandey Hitoshi Takagi Antonio Norio Nakagaito Daulat Ram Saini Sung-Hoon Ahn 《Composites Part B》2012,43(7):2822-2826
Biopolymer based composites have been employed in numerous applications with increasing interest not only due to renewable, eco-friendly nature, but also because of the flexibility in processing conditions and competitive cost of their end products. The conductive materials from biopolymers have been found applicable in robots, medical imaging, sensitive membranes, actuators, visual displays, electronic wiring and shielding, and components in batteries. Cellulose is one of the most abundant biopolymers in the nature, which has received special attention for development of conducting materials due to biocompatibility for protein and drug immobilization and ability to form the composites with synthetic polymers. The present review is aimed to provide concisely the current status in this field of conducting composites from cellulose, with brief discussions of associated problems and future applications. 相似文献
45.
Sunil Pandey Ritu Shah Ashmi Mewada Mukeshchand Thakur Goldie Oza Madhuri Sharon 《Journal of materials science. Materials in medicine》2013,24(7):1671-1681
Use of cysteamine hydrochloride (Cys-HCl) protected gold nanorods (GNRs) as efficient carrier of widely used anti-cancer drug doxorubicin using folic acid as navigational molecule is presented in this work. GNRs were found to have excellent drug loading capacity of >97 %. A detailed comprehension of in vitro drug release profile under ideal physiological condition was found to obey 1st order kinetics at pH 6.8, 5.3 and 7.2, an ideal milieu for drug delivery to solid tumours. 相似文献
46.
Vipin Pandey S. K. Tauseef S. M. Abbasi Tasneem Abbasi S. A. 《Journal of Failure Analysis and Prevention》2018,18(5):1320-1320
Journal of Failure Analysis and Prevention - In the original version of this article, Vipin’s name was incorrect. It is correct as reflected here. The original article has also been corrected. 相似文献
47.
Ranvir Singh Panwar Suresh Kumar Ratandeep Pandey Om Prakash Pandey 《Tribology Letters》2014,55(1):83-92
In the present work, a detailed study of ceramic reinforcement of different size ranges in the matrix of LM13 alloy on the friction and wear behavior has been carried out. For this purpose, LM13/Zr composite containing 10 wt% zircon sand particles of different size ranges using stir casting process has been developed. Zircon sand particles were incorporated in two ways: firstly as single size reinforcement and secondly dual size reinforcement. Durability of the composites was tested by finding the wear rate of the composite against the steel disk by pin-on-disk method. Addition of zircon sand particles in the LM13 alloy improves the hardness of the composite as well as wear resistance. Wear rate of the developed composites was tested under different test conditions by varying the applied load and ambient temperatures. Wear rate of the composite changes significantly at different ambient temperatures. SEM analysis of the worn surfaces was done to know the operative wear mechanism. 相似文献
48.
15–25 wt% zirconia (stabilized with 14 mol% ceria) toughened alumina was synthesized by co-precipitation technique. The synthesized powders were calcined at different temperatures, compacted and conventionally sintered following two steps sintering process. Uniformly distributed submicron sized grains with Vickers' hardness value up to 1730±6HV20 were achieved after conventional sintering. In order to assess the ageing behaviour, samples were hydrothermally treated (in vitro) at 134 °C under 0.2 MPa in presence of simulated body fluid. Rietveld refinement of the X-ray diffraction patterns was carried out to estimate the phase content after calcination, sintering and after different stages of hydrothermal treatment. No significant phase change (only ∼3%) was observed even after 100 h of hydrothermal treatment. Very few bulged grains (resulted from the tetragonal to monoclinic phase transformation) on the surface and slight decrease in hardness value were observed after hydrothermal treatment. Fretting wear in dry condition was carried out taking ball on flat geometry for 105 cycles at different loads before and after hydrothermal treatment. Wear volumes were directly estimated from the surface scanning of the wear scar using profilometer. Transition of wear and its related mechanisms at different loads along with the effect of ageing on wear were discussed. 相似文献
49.
The Grüneisen parameter (γ) is of considerable importance to Earth scientists because it sets limitations on the thermo elastic properties of the lower mantle and core. However, there are several formulations of the Grüneisen parameter in frequent use which not only give different values for Grüneisen parameter at ambient pressure but also predict a varying dependence of Grüneisen parameter as a function of compression. The Grüneisen parameter is directly related to the equation of state (EOS), yet it is often the case that both the form of and the EOS are chosen independently of each other and somewhat arbitrarily. In this paper we have assessed some of the more common definitions of the Grüneisen parameter and the EOS's, and have applied them to test the validity of EOS for six different bulk metallic glasses. 相似文献
50.
Pramod Chaitanya Ritu Mishra Pradeep Kumar Ahirwal O. P. Thakur Lakshman Pandey 《Integrated ferroelectrics》2015,159(1):121-126
The electrical behavior of strontium titanate borosilicate glass ceramics (SrO.TiO2- 2SiO2.B2O3) with additives K2O, La2O3, CoO and Nb2O5 was studied by using Impedance Spectroscopy as a function of temperature and composition. An equivalent circuit model having three parallel RC's connected in series with a capacitor C4 could represent the data well. By comparing the complex modulus plots with simulated ones and looking at the values of the time constants these RC's were attributed to represent crystalline, glassy and glass-crystal interface regions of the glass- ceramic whereas C4 represented the glass-ceramic sample and contact electrode interface. When the glass ceramic sample contained only SrTiO3 crystalline phase and the remaining glassy matrix, the interface capacitance showed an Arrhenius type of nature with an activation energy (0.11 ± 0.04) eV and when the glass- ceramic sample contained number of crystalline phases no clear cut trend appeared. These findings are useful in selecting suitable electrodes for applications as well as in deciding upon experimental techniques for measurement of dielectric constants of materials. 相似文献