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101.
In this paper we establish sufficient conditions for the approximate controllability of impulsive neutral functional evolution integrodifferential systems in Hilbert spaces. Also we study the exact controllability of the same system. The conditions are obtained by using Schauder’s fixed point theorem when the operator is compact and the Banach fixed point theorem when the operator is not compact. The results are obtained by using the evolution operators. 相似文献
102.
Niranjan Balachandran 《Designs, Codes and Cryptography》2012,65(3):353-364
Let ${\mathcal{F}}$ be a (0, 1) matrix. A (0, 1) matrix ${\mathcal{M}}$ is said to have ${\mathcal{F}}$ as a configuration if there is a submatrix of ${\mathcal{M}}$ which is a row and column permutation of ${\mathcal{F}}$ . We say that a matrix ${\mathcal{M}}$ is simple if it has no repeated columns. For a given ${v \in \mathbb{N}}$ , we shall denote by forb ${(v, \mathcal{F})}$ the maximum number of columns in a simple (0, 1) matrix with v rows for which ${\mathcal{F}}$ does not occur as a configuration. We say that a matrix ${\mathcal{M}}$ is maximal for ${\mathcal{F}}$ if ${\mathcal{M}}$ has forb ${(v, \mathcal{F})}$ columns. In this paper we show that for certain natural choices of ${\mathcal{F}}$ , forb ${(v, \mathcal{F})\leq\frac{\binom{v}{t}}{t+1}}$ . In particular this gives an extremal characterization for Steiner t-designs as maximal (0, 1) matrices in terms of certain forbidden configurations. 相似文献
103.
Parimala K Balachandran V 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,81(1):711-723
The Fourier transform infrared (FTIR) and FT Raman spectra of p-toluenesulfonyl isocyanate (p-tosyl isocyanate) have been measured. The molecular geometry, vibrational frequencies, infrared intensities, Raman activities and atomic charges have been calculated by using ab initio HF and density functional theory calculation (B3LYP) with 6-311+G(d,p) basis set. Complete vibrational assignment and analysis of the fundamental modes of the compound were carried out using the observed FTIR and FT Raman data. The thermodynamic functions of the title compound were also performed with the aid of HF/6-311+G(d,p) and B3LYP/6-311+G(d,p) levels of theory. Simulated FTIR and FT Raman spectra for p-tosyl isocyanate showed good agreement with the observed spectra. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. The dipole moment (μ), polarizability (α) and the hyperpolarizability (β) values of the investigated molecule have been computed using HF and B3LYP methods. 相似文献
104.
Meiya Li B. Ma B.L. Fisher V.A. Maroni U. Balachandran 《Solid State Communications》2004,131(2):101-105
Biaxially textured YBa2Cu3O7−x (YBCO) films were grown on non-textured metal substrates with inclined-substrate-deposited (ISD) MgO as template. The biaxial texture feature of the films was examined by X-ray pole-figure analysis, φ-scan, and 2θ-scan. A tilt angle of 32° of the MgO[001] with respect to the substrate normal was observed. Epitaxial growth of YBCO films with c-axis tilt angle of 32° with respect to the substrate normal was obtained on these substrates with SrTiO3(STO) as buffer layer. Whereas, by choosing yttria-stabilized ZrO2 and CeO2 instead of STO as buffer layer, a c-axis untilted YBCO film was obtained. Higher values of Tc=91 K and Jc=5.5×105 A/cm2 were obtained on the c-axis untilted YBCO films with 0.46 μm thickness at 77 K in zero field. Comparative studies revealed a unique role of CeO2 in controlling the orientation of the YBCO films grown on ISD-MgO buffered metal substrates. 相似文献
105.
106.
In this paper, the mean-square stability of second-order Runge–Kutta schemes for multi-dimensional linear stochastic differential systems is studied. Motivated by the work of Tocino [Mean-square stability of second-order Runge–Kutta methods for stochastic differential equations, J. Comput. Appl. Math. 175 (2005) 355–367] and Saito and Mitsui [Mean-square stability of numerical schemes for stochastic differential systems, in: International Conference on SCIentific Computation and Differential Equations, July 29–August 3 2001, Vancouver, British Columbia, Canada] we investigate the mean-square stability of second-order Runge–Kutta schemes for multi-dimensional linear stochastic differential systems with one multiplicative noise. Stability criteria are established and numerical examples that confirm the theoretical results are also presented. 相似文献
107.
Sangeetha S Sathyaraj G Muthamilselvan D Vaidyanathan VG Nair BU 《Dalton transactions (Cambridge, England : 2003)》2012,41(19):5769-5773
We report two fluorophores with open coordination sites for specific sensing of Ni(2+) and Cu(2+) ions via a simple synthetic route. The fluorescence activity was completely quenched on coordination of the metal ions with the phenanthroline ring present in the fluorophore as is clearly evident from the photophysical studies. 相似文献
108.
K. Balachandran P. Balasubramaniam J. P. Dauer 《Journal of Optimization Theory and Applications》1996,88(1):61-75
Sufficient conditions for the local null controllability of non-linear functional differential systems with unbounded linear operators in Banach space are established. The results are obtained using the semigroup of linear operators, fractional powers of operators, and the Schauder fixed-point theorem. Applications to parabolic differential systems are given.The work of the first and second authors was supported by CSIR, New Delhi, India. 相似文献
109.
Makoto Suto Hiroaki Mamiya Ryo Kasuya Balachandran Jeyadevan 《Journal of magnetism and magnetic materials》2009,321(10):1493-1496
The relative contributions of Néel and Brownian relaxations on magnetic heat dissipation were studied by investigating the physical, magnetic and heating characteristics of magnetite nanoparticle suspensions with average diameters of 12.5 and 15.7 nm. Heating characteristics depended on the dispersion states of particles. The specific absorption rates (SAR) dropped by 27% for the 12.5 nm particles to 16.8×10−9 W g−1 Oe−2 Hz−1 and by 67% for the 15.7 nm particles to 9.69×10−9 W g−1 Oe−2 Hz−1, when the particle rotation was suppressed by dispersing magnetite nanoparticles in hydro-gel. 相似文献
110.
This paper models a decentralized firm under information asymmetry and effort disutility on the part of managers. We assume that managers choose efforts before observing some private information. However, after the effort choice managers receive private information on their cost parameters which they report to the headquarters. There exist many situations in which managers need to take efforts before obtaining private information; for example, the regular maintenance effort on the machine, the effort on R&D for reducing costs and the effort taken to build relationships with the supplier. Two models are considered in this paper based on the timing of acquisition of private information by the managers. We derive optimal coordination mechanisms to facilitate internal transactions for the models. The equilibrium outcome of this paper suggests that: 1) regardless of the timing of managers' information acquisition, the optimal output level under asymmetric information can have overproduction or underproduction when compared with the full information optimal output; 2) under certain demand conditions managers cannot receive any information rent benefit for their private information even if they have the option to renege on the contract after obtaining their private information. 相似文献