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51.
In the above-named work (see ibid., vol.38, p.51-7, April 1989), S. Lafiti and A. El-Amawy apply, in a straightforward manner, the method developed by A.D. Singh (1985) to calculate lower bounds for the yield of nonplanar interstitial redundancy topologies of processor arrays with spare processors. In their introduction, they claim that the models suggested by I. Koren and D.K. Pradhan (1987) are highly theoretical since the number of states in the Markov model might be very large and the determination of the transition rates might be intractable. They add that applying some empirical rules, as suggested by Koren and Pradhan (1987), can lead to unrealistic results and may require a large number of computations. They also claim that the model of Koren and Pradhan does not suggest an algorithm to replace faulty elements. They conclude that a simpler model, like the one proposed by Singh, is needed for calculating the yield of fault-tolerant processor arrays. In the present comment, Koren and Pradhan respond to the above comments and attempt to clarify the differences between their yield analysis and that of Singh 相似文献
52.
T. V. Narasaiah R. N. P. Choudhary A. K. Pradhan 《Journal of Materials Science》1987,22(10):3571-3575
The Raman and infrared spectra of polycrystalline samples TlH2AsO4, TlD2AsO4, TlH2PO4 and TlD2PO4 have been investigated at 300 K in the frequency ranges 0 to 4000 and 200 to 4000cm–1 respectively. The assignment of lattice, internal, and OH group vibrations has been approximated in terms of symmetry species. Although all the vibrations follow more or less the space group symmetry, the internal vibrations do not completely fulfill the requirements of the symmetry rule. The isotope effect was observed prominently on both compounds in Raman and infrared spectra. An attempt has been made to assign and explain the results. 相似文献
53.
This study examined the effects of procedural justice on state-dependent self-esteem using the group-value model and attribution theory to present competing theoretical perspectives. The group-value model predicts a positive relationship between self-esteem and fair procedures. In contrast, attribution theory suggests procedural fairness interacts with outcome favorability to influence self-esteem. Thus, fair procedures will result in higher self-esteem ratings than unfair procedures when the outcome is positive but will result in lower self-esteem ratings than unfair procedures when the outcome is negative. The results of a laboratory and field study provide converging evidence to support the attribution theory predictions. The results of a 2nd laboratory study suggest that self-esteem is influenced by outcome expectancies, not actual outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
54.
Seema Verma S. D. Pradhan Renu Pasricha S. R. Sainkar P. A. Joy 《Journal of the American Ceramic Society》2005,88(9):2597-2599
Nanosized NiZn ferrite powder is synthesized by a low-temperature method, using a unique combination of citric acid and glycine. An appropriate molar ratio of both citric acid and glycine offers a low-temperature synthetic route by incorporating the complexation behavior of citric acid and the combustion nature of glycine. Thermal decomposition/controlled autocatalytic combustion of the composite gel occurs at a low temperature of around 175°C, with the evolution of a large amount of gases. Transmission electron microscopic studies showed that the average particle size of the ferrite obtained is ∼2.5 nm, with a narrow size distribution. Uniformly distributed fine-grained microstructure with low porosity is obtained for a sample sintered at 1000°C. 相似文献
55.
Epoxidation of Canola Oil with Hydrogen Peroxide Catalyzed by Acidic Ion Exchange Resin 总被引:2,自引:0,他引:2
Rubeena Mungroo Narayan C. Pradhan Vaibhav V. Goud Ajay K. Dalai 《Journal of the American Oil Chemists' Society》2008,85(9):887-896
Canola oil with an iodine value of 112/100 g, and containing 60% oleic acid and 20% linoleic acid, was epoxidised using a
peroxyacid generated in situ from hydrogen peroxide and a carboxylic acid (acetic or formic acid) in the presence of an acidic
ion exchange resin (AIER), Amberlite IR 120H. Acetic acid was found to be a better oxygen carrier than formic acid, as it
produced about 10% more conversion of ethylenic unsaturation to oxirane than that produced by formic acid under otherwise
identical conditions. A detailed process developmental study was then performed with the acetic acid/AIER combination. The
parameters optimised were temperature (65 °C), acetic acid to ethylenic unsaturation molar ratio (0.5), hydrogen peroxide
to ethylenic unsaturation molar ratio (1.5), and AIER loading (22%). An iodine conversion of 88.4% and a relative conversion
to oxirane of 90% were obtained at the optimum reaction conditions. The heterogeneous catalyst, AIER, was found to be reusable
and exhibited a negligible loss in activity. 相似文献
56.
57.
Removal of p-nitrophenol using hydrodynamic cavitation and Fenton chemistry at pilot scale operation
Amey A. Pradhan Parag R. Gogate 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2010,156(1):77-82
In the current work removal of p-nitrophenol has been investigated using hydrodynamic cavitation, either operated individually or in combination with H2O2 and conventional Fenton process. In hydrodynamic cavitation, two different cavitating devices viz. orifice plate and venturi have been used. Effect of different operating parameters such as initial concentration (5 g/l and 10 g/l), inlet pressure (over a range 5.7–42.6 psi) and pH (over a range 2–8) on the extent of removal has been investigated. In conventional Fenton process two loadings of FeSO4, 0.5 g/l and 1 g/l were investigated and three ratios of FeSO4:H2O2 viz. 1:5, 1:7.5 and 1:10 were used. Removal observed with venturi was higher than with orifice plate in combination with Fenton chemistry. For 5 g/l initial concentration of p-nitrophenol, maximum removal of 63.2% was observed whereas for 10 g/l solution it was 56.2%. 相似文献
58.
59.
Debabrata Pradhan Akshya Kumar Guin Pankaj Raju Manindra Manna Monojit Dutta T. Venugopalan 《Journal of Materials Engineering and Performance》2014,23(9):3336-3346
Galvannealed steel sheets (GA) have become the mainstream steel sheet for automobile applications because of their superior corrosion resistance, paintability, and weldability. To impart specific properties, different coatings on GA steel sheet were reported to improve properties further. In this context, we have developed an electroplating process (flash coating) for bright and adherent Fe-Zn alloy coating on GA steel sheet to enhance performances such as weldability, frictional behavior, phosphatability, and defect coverage. A comparative study with bare GA steel sheet was carried out for better elastration. The electroplating time was reduced below 10 s for practical applicability in an industrial coating line by modulating the bath composition. Electroplating was performed at current density of 200-500 A/m2 which yielded with higher cathode current efficiency of 85-95%. The performance results show that Fe-10 wt.% Zn-coated GA steel sheet (coating time 7 s) has better spot weldability, lower dynamic coefficient of friction (0.06-0.07 in lubrication), and better corrosion resistance compared to bare GA steel sheet. Uniform phosphate coating with globular crystal size of 2-5 µm was obtained on Fe-Zn flash-coated GA steel sheet. Hopeite was the main phosphate compound (77.9 wt.%) identified along with spencerite (13.6 wt.%) and phosphophyllite (8.5 wt.%). 相似文献
60.
Haris B?C G. Pradhan A. Misra S. R. M. Prasanna R. K. Das R. Sinha 《International Journal of Speech Technology》2012,15(4):441-453
In this paper we describe the collection and organization of the speaker recognition database in Indian scenario named as IITG Multivariability Speaker Recognition Database. The database contains speech from 451 speakers speaking English and other Indian languages both in conversational and read speech styles recorded using various sensors in parallel under different environmental conditions. The database is organized into four phases on the basis of different conditions employed for the recording. The results of the initial studies conducted on a speaker verification system exploring the impact of mismatch in training and test conditions using the collected data are also included. A copy of this database can be obtained from the authors by contacting them. 相似文献