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61.
Analysis of refractometric fiber optic state-of-charge (SOC) monitoring sensor for lead acid battery
In situ monitoring of the state of charge (SOC) of lead acid battery is important to understand the residual electrical energy. Usage of battery reduces the charge content of the active electrolyte which in turn changes its refractive index. This paper reports refractometric fiber optic sensor developed for on-line monitoring of SOC. The SOC is monitored during discharging phases of the battery using the developed fiber optic sensor probe along with terminal voltage, temperature and depth of discharge using a LABVIEW based data acquisition system. The paper gives the working principle, design and construction details, results and calibration of the fiber optic sensor (FOS) probe. The in situ monitoring capability of the developed FOS is demonstrated in comparison with the contemporary off-line methods of specific gravity and terminal voltage measurements. 相似文献
62.
63.
Magnetic metal and metal oxide nanoparticles capped with alkylamines have been synthesized and characterized by transmission
electron microscopy. X-ray diffraction, energy dispersive X-ray analysis and magnetization measurements. Core-shell Pd-Ni
particles with composition, Pd561Ni3000, (diameter ∼3.3 nm) are superparamagnetic at 5 K and organize themselves into two-dimensional crystalline arrays. Similar
arrays are obtained with Pd561Ni3000Pd1500 nanoparticles containing an additional Pd shell. Magnetic spinel particles of γ-Fe2O3, Fe3O4 and CoFe2O4 of average diameters in the 4–6 nm range coated with octylamine are all supermagnetic at room temperature and yield close-packed
disordered arrays. Relatively regular arrays are formed by dodecylaminecapped Fe3O4 nanoparticles (∼8.6 nm diameter) while well-ordered hexagonal arrays were obtained with octylamine-covered Co3O4 nanoparticles (∼4.2 nm diameter). 相似文献
64.
Craig F Ferris Tara Stolberg Praveen Kulkarni Murali Murugavel Robert Blanchard D Caroline Blanchard Marcelo Febo Mathew Brevard Neal G Simon 《BMC neuroscience》2008,9(1):111
Background
With the advent of functional magnetic resonance imaging (fMRI) in awake animals it is possible to resolve patterns of neuronal activity across the entire brain with high spatial and temporal resolution. Synchronized changes in neuronal activity across multiple brain areas can be viewed as functional neuroanatomical circuits coordinating the thoughts, memories and emotions for particular behaviors. To this end, fMRI in conscious rats combined with 3D computational analysis was used to identifying the putative distributed neural circuit involved in aggressive motivation and how this circuit is affected by drugs that block aggressive behavior. 相似文献65.
A genetic algorithm (GA) based strategy is presented for deducing an exact or near-exact functional form from a time series. The GA formalism proposed here utilizes (i) the "postfix" representation with a view to reduce the procedural complexities and (ii) the "elitist mating" scheme to produce fitter offspring strings. The GA procedure is exemplified by considering chaotic time series of the well-known logistic, Henon and universal maps. The GA correctly recovers the underlying functional forms for the respective time series. Measurements from a number of finite-dimensional physical, biological, and other systems often give rise to complex time series and the presented methodology should prove useful in obtaining functional forms describing accurately the evolution of the time series. (c) 1999 American Institute of Physics. 相似文献
66.
A fluctuation theory for Markov chains on an ordered countable state space is developed, using ladder processes. These are shown to be Markov renewal processes. Results are given for the joint distribution of the extremum (maximum or minimum) and the first time the extremum is achieved. Also a new classification of the states of a Markov chain is suggested. Two examples are given. 相似文献
67.
Results of the investigation on the spectral characteristics of PL of SrS:Cu phosphors are presented. Probable emitters for the three observed bands, viz. 4710 Å, 5200 Å and 5480 Å, have been suggested. 相似文献
68.
Various mathematical formulations are available for situations represented by vehicle routing problems. The assignment-based integer programming formulations of these problems are more common and easy to understand. Such formulations are discussed in this paper and a much simpler formulation for the vechicle routing problem is presented for the case, when all the vehicles have the same load capacity and maximum allowable cost per route. 相似文献
69.
S. A. Stern S. S. Kulkarni H. L. Frisch 《Journal of Polymer Science.Polymer Physics》1983,21(3):467-481
Permeability coefficients have been measured for CO2, CH4, C2H4, and C3H8 in polyethylene membranes at temperatures of 5, 20, and 35°C and at applied gas pressures of up to 30 atm. The temperature and pressure dependence of the permeability coefficients was represented satisfactorily by an extension of Fujita's free-volume model of diffusion of small molecules in polymers. The results of the present steady-state permeability measurements provide further support for the conclusion reached from previous unsteady-state diffusivity measurements that Fujita's model is applicable to the transport of small molecules, such as CO2, CH4, C2H4, and C3H8, in polyethylene. It was previously thought that this model is applicable only to the transport of larger molecules, such as of organic vapors, in polymers. 相似文献
70.
V. G. Kulkarni R. G. Lagu Girish Chandra B. V. Thosar 《Proceedings Mathematical Sciences》1970,72(2):88-93
The value (τ2) and the intensity (I2) of the delayed component in the lifetime spectra of positrons annihilating in annealed and quenched teflon and in sulphur and crystex (polymer sulphur), at room temperature and at 77° K are reported. These data and the X-ray diffraction patterns for these materials are discussed in terms of the free volume model for the formation and quenching of positronium atoms in molecular materials. 相似文献