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41.
Ganapati Panda Pyari Mohan Pradhan Babita Majhi 《Expert systems with applications》2011,38(10):12671-12683
Conventional derivative based learning rule poses stability problem when used in adaptive identification of infinite impulse response (IIR) systems. In addition the performance of these methods substantially deteriorates when reduced order adaptive models are used for such identification. In this paper the IIR system identification task is formulated as an optimization problem and a recently introduced cat swarm optimization (CSO) is used to develop a new population based learning rule for the model. Both actual and reduced order identification of few benchmarked IIR plants is carried out through simulation study. The results demonstrate superior identification performance of the new method compared to that achieved by genetic algorithm (GA) and particle swarm optimization (PSO) based identification. 相似文献
42.
Polyacrylonitrile/functionalized single-walled carbon nanotubes (PAN/f-SWCNTs) nanocomposites were synthesized by an emulsifier-free in situ polymerization process. Interaction of polyacrylonitrile with functionalized single-walled carbon nanotubes was evidenced by ultraviolet-visible and Fourier transforms infrared spectroscopy. The structure and morphology of nanocomposites were characterized by X-ray diffraction, field emission scanning electron microscopy and high resolution transmission electron microscopy. Electrical conductivity was found to be increased by addition of f-SWCNTs. Thermogravimetric analysis study of PAN/f-SWCNT nanocomposites show more thermal resistance compared to the virgin PAN. The oxygen barrier property of PAN/f-SWCNT nanocomposites was reduced by eight times with increasing f-SWCNTs proportions. 相似文献
43.
A new multibranched octopus-type structure of carbon nanofibers is synthesized from a natural precursor, camphor, by a thermal chemical vapor deposition technique. An alloy of Cu:Ni catalyst is prepared by electrochemically coating nickel on a copper sheet, with nickel sulfate as an electrolyte, and heating that nickel-coated copper sheet to a higher temperature. Deposition of carbon on these substrates leads to the formation of a branched nanostructure in the temperature range of 923 K to 1023 K. The fiber diameter increases from 30 nm to 250 nm with increasing pyrolysis temperature. Detailed morphology and the internal structure of these fibers are studied by scanning and transmission electron microscopy. 相似文献
44.
Sliding mode controller design via delay-dependent H∞ stabilization criterion for load frequency regulation 下载免费PDF全文
This work presents a control approach based on sliding-mode-control (SMC) to design robust H∞ state feedback
controllers for load frequency regulation of delayed interconnected power system (IPS) with parametric uncertainties.
Considering both state feedback control strategy and delayed feedback control strategy, two SMC laws are proposed.
The proposed control laws are designed to improve the stability and disturbance rejection performance of delayed
IPS, while stabilization criteria in the form of linear matrix inequality are derived by choosing a Lyapunov–Krasovskii
functional. An artifcial time-delay is incorporated in the control law design of the delayed feedback control structure to enhance the controller performance. A numerical example is considered to study the control performance
of the proposed controllers and simulation results are provided to observe the dynamic response of the IPS. 相似文献
45.
Sandeep Panda Pradeep Chandra Rout Chinmaya Kumar Sarangi Srabani Mishra Nilotpala Pradhan Umaballav Mohapatra Tondepu Subbaiah Lala Behari Sukla Barada Kanta Mishra 《Korean Journal of Chemical Engineering》2014,31(3):452-460
Bioleaching studies for chalcopyrite contained ball mill spillages are very scarce in the literature. We developed a process flow sheet for the recovery of copper metal from surface activated (600 °C, 15 min) ball mill spillage through bio-hydrometallurgical processing route. Bioleaching of the activated sample using a mixed meso-acidophilic bacterial consortium predominantly A. ferrooxidans strains was found to be effective at a lixiviant flow rate of 1.5 L/h, enabling a maximum 72.36% copper recovery in 20 days. Mineralogical as well as morphological changes over the sample surface were seen to trigger the bioleaching efficiency of meso-acidophiles, thereby contributing towards an enhanced copper recovery from the ball mill spillage. The bio-leach liquor containing 1.84 g/L Cu was purified through solvent extraction using LIX 84I in kerosene prior to the recovery of copper metal by electrowinning. Purity of the copper produced through this process was 99.99%. 相似文献
46.
Kumari S. Panigrahi A. Singh S. K. Mohapatra M. Khanna A. S. Mishra S. K. Pradhan S. K. 《Journal of Applied Electrochemistry》2019,49(12):1157-1166
Journal of Applied Electrochemistry - The present work is focused on the effects of graphene addition on the electrochemical performance of environmentally benign nanostructured... 相似文献
47.
Empirical studies in software engineering can involve a variety of organizations, each with their own set of policies and procedures geared at safeguarding the interests and responsibilities of the researchers, students, the collaborating company, the university, and possibly national funding agencies like the National Science Foundation and the National Institute of Health. Each of these organizations have differing goals for participating in these studies and bring widely different cultures and expectations to the table. While policies, procedures, contracts, and agreements set expectations, they by themselves cannot ensure ethical behavior. This position paper describes some of the common approaches to encourage ethical behavior and their limits for enforcing ethical behavior. 相似文献
48.
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
49.
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
50.
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