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891.
In this article, use of Zernike moments is presented for invariant recognition of Gurumukhi characters. Zernike moments belong to a class of continuous orthogonal moments defined over a unit circle. So, for a square image, computations of Zernike moments involve a certain square-to-circle mapping to map the pixel coordinates within the range of the unit circle. There exist two forms of mapping, which are used by various authors in their research works. Here, a computational framework has been proposed for calculation of Zernike moments using both mapping techniques, and a comparison between the performances of both of these mapping techniques is shown through a series of extensive experiments. 相似文献
892.
Anurag Shukla N. Sukavanam D. N. Pandey Urvashi Arora 《Circuits, Systems, and Signal Processing》2016,35(9):3339-3354
This paper deals with the approximate controllability of second-order semilinear control system in Hilbert spaces under the assumption that the corresponding linear system is approximately controllable. The control function for this system is suitably constructed, and the sufficient conditions for the approximate controllability of the proposed problem in Hilbert spaces are established. The results are obtained when the nonlinearity satisfying the monotone condition and integral contractor condition. Finally, an example is provided to illustrate the application of the obtained results. 相似文献
893.
Viet Tu Nguyen Jae-chun Lee Jinki Jeong Byung-Su Kim B. D. Pandey 《Metals and Materials International》2014,20(2):357-365
This paper focuses on the extractive separation and selective recovery of cobalt, nickel and lithium from the sulfate leachate of cathode scrap generated during manufacture of lithium ion batteries (LIBs). The conditions for extraction, scrubbing and stripping of cobalt from nickel and lithium are optimized with an aqueous feed containing 25.1 g·dm?3 cobalt, 2.54 g·dm?3 nickel and 6.2 g·dm?3 lithium using Na-PC-88A. 99.8% Co is extracted with 60% Na-0.56 mol·dm?3 PC-88A in two counter-current stages at an O/A phase ratio of 3/1 and an equilibrium pH of 4.5. The “crowding effect” shown for the first time provides effective scrubbing of impurities (Ni and Li) with 2.0 g·dm?3 CoSO4 solution. The McCabe-Thiele diagram predicts the scrubbing of 99.9% Ni and 99.9% Li at an equilibrium pH of 4.75 and O/A of 2/1 in two stages. High purity (99.9%) cobalt sulfate along with Ni and Li from the leach liquor of cathode scrap is recovered by solvent extraction. The proposed process ensures complete recycling of the waste of the manufacturing process of LIBs. 相似文献
894.
Sukanya Pradhan Priyanka Pandey Smita Mohanty Sanjay K. Nayak 《Journal of Coatings Technology and Research》2017,14(4):915-926
This study focuses on synthesis of waterborne epoxy (WBE) derived from epoxidized soybean oil (ESO) and its compatibility with water-dispersible curing agent Pripol 1009, which is a bioderived long-chain dimer acid. The reaction parameters involved in the synthesis of WBE from ESO have been optimized based on physicochemical properties like hydroxyl value, epoxy equivalent value and degree of solubility of WBE. The WBE obtained after 5 and 6 h of reaction time was found to be of optimum composition with balanced physicochemical properties. The mechanical, thermal and physicochemical properties of WBE obtained after 6 h of reaction time revealed relatively better performance characteristics as compared to ESO. 相似文献
895.
Murraya koenigii (L.) Spreng. ameliorates insulin resistance in dexamethasone‐treated mice by enhancing peripheral insulin sensitivity
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896.
Mandeep Kaur Gurbinder Kaur O.P. Pandey K. Singh V. Kumar 《International Journal of Hydrogen Energy》2017,42(25):16244-16257
High temperature hermetic sealants are required for the stability and good efficiency of the solid oxide fuel cells (SOFCs). Glass and glass ceramics are promising sealant materials due to their desirable properties and flexible compositions. In the present study, the novel glass series (10 + x) CaO-(10 ? x) MgO-10SrO-10B2O3-20Al2O3-40SiO2 (x = 0, 2.5, 5, 7.5) has been synthesized via melt quenching route. These glass/glass ceramics are characterized by X-ray diffraction to evaluate the amorphous nature and phase formation, respectively. The activation energy has been analyzed by using three different theoretical models – Kissinger Model, Moynihan Model and Augis and Benett Model. In addition to this, the characteristic glass temperatures and coefficient of thermal expansion (CTE) have been obtained from DTA, differential DTA (DDTA) and Dilatometry. Various stability parameters like Hruby parameter, Saad Parameter, fluctuation free volume (fg) and bulk thermal expansion coefficient (αf) are also calculated with varying CaO/MgO ratio (R). Furthermore, to analyze the stability of the glasses with varying CaO/MgO ratio over a broader range of temperature, k parameters i.e. kb (T) and kf (T) are also evaluated for different heating rates. The diffusion couples of glasses with pre oxidized Crofer 22APU and YSZ fabricated at 850 °C for 500 h have been characterized using scanning electron microscopy (SEM) and X-ray dot mapping to investigate the sealing characteristics with varying CaO/MgO ratio. The glass series 15 CaMg is very stable and promises to be a good sealant for solid oxide fuel cells. 相似文献
897.
Dhanya Gangadharan K. Madhavan Nampoothiri Swetha Sivaramakrishnan Ashok Pandey 《Food research international (Ottawa, Ont.)》2009,42(4):436-442
The major concern in an enzymatic process is the instability of the enzyme under repetitive or prolonged use and inhibition by high substrate and product concentration. Immobilization is a very effective alternative in overcoming problems of instability and repetitive use of enzymes. Entrapment method of immobilization is advantageous over other methods as they do not involve chemical modification of the enzyme. α-Amylase produced by Bacillus amyloliquefaciens ATCC 23842 was immobilized in calcium alginate beads and used for the effective hydrolysis of soluble and raw potato starch which was comparable to the free enzyme. The levels of parameters (sodium alginate, calcium chloride and curing time) that significantly influence the immobilization of α-amylase in calcium alginate were analyzed and optimized using response surface methodology. Reactor studies were performed to study the reusability and operational stability of the beads. The alginate beads retained more than 60% of their initial efficiency after five batches of successive use and 40% of efficiency was exhibited in the 6th and 7th batch run of 6 h duration. 相似文献
898.
An appreciable electric current is observed in a system consisting of a polyvinyl formal (PVF) film in a sandwich configuration,
in the temperature range 30–110°C. The maximum value of the current during first heating is found to be of the order of 10−10 A and its thermograms exhibit one transition (i.e. current peak) at around 60°C. The position of the current peak in thermal
spectrum shifts with the heating rate. A temperature dependence of the open circuit voltage is also observed. The activation
energy of the process responsible for the current is determined. The magnitude of the current is more in the case of dissimilar
electrode systems. It is proposed that the electric current arising from unpolarized metal-polymer-metal system is a water
activated phenomenon, which is influenced by the transitional changes of the polymer. 相似文献
899.
A. Chakraborty M. Manna A. Pandey M. Dutta 《Journal of Materials Processing Technology》2013,213(9):1501-1508
Tube galvanizing is a very old and important process industrially. One of the significant process steps in tube galvanizing is the use of flux materials on cleaned tubes for temporary protection before dipping into the liquid zinc bath. However, the fluxing operation is somewhat hazardous and also causes zinc loss by dross and ash generation. An attempt has been made here for the first time to replace fluxing operation by applying a thin metal flash coating on clean tubes prior to galvanizing. The galvanized tubes are then characterized by SEM and EDS to find out the coating thickness and evolved phases. The galvanized tubes are subjected to corrosion tests and coating adhesion tests. The results are very encouraging confirming the presence of desired phases along with excellent corrosion resistance of these tubes. 相似文献
900.
M. D. Pandey 《Structural Safety》2001,23(4):345-363
Extreme quantile estimation in the peaks-over-threshold (POT) method is based on the Pareto distribution model for peaks of a time series exceeding a high threshold. However, a major practical difficulty associated with this approach is the large and erratic variability of quantile estimates with respect to the threshold value, which is not known a priori. Recognizing the limited applicability of the Pareto model to a narrow and unidentifiable range of peak data, the paper presents a more general non-parametric probabilistic model to improve the statistical accuracy and of POT estimates. The proposed approach relies on a quantitative notion of uncertainty and the minimum cross-entropy principle (Cross-Ent), commonly used in information theory and signal analysis. The model combine a suitable prior distribution with sample estimates of probability-weighted-moments, which exhibit much smaller sampling uncertainty than estimates of ordinary moments. The performance of the Cross-Ent approach is compared with a widely used Pareto model of peak data and an exponential model of transformed data. Examples based on simulated data illustrate that Cross-Ent estimates of 50 and 1000-year quantiles are almost unbiased and insensitive to the threshold value. The analysis of US wind speed data also reveals a remarkably stable trend of Cross-Ent estimates with very limited threshold sensitivity, which is in clear contrast with rapidly fluctuating estimates obtained from the other two methods. 相似文献