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881.
Suresh P. Sethi 《Operations Research Letters》1984,3(1):13-17
This paper develops an approach to the valuation of risky streams defined by a class of stochastic processes. The valuation is given by a linear functional, which is an extension of the market valuations of the marketed assets. Provided that there exists an interest rate process, it is possible to represent the valuation functional as an appropriate expectation defined on the space of integrable random variables. The paper concludes with the relationship of our approach to the existing literature. 相似文献
882.
Manoj Parameswaran Ganapathy Balaji Tan Mein Jin Chellappan Vijila Sajini Vadukumpully Zhu Furong Suresh Valiyaveettil 《Organic Electronics》2009,10(8):1534-1540
Charge mobility characteristics of a newly synthesised 2,6-bis[2-(9,9-dihexyl-9H-fluorene)]-N-(4-hexylphenyl)-dithieno[3,2-b:2′,3′-d]pyrrole oligomer (DTP-FLU) was studied as a function of electric field and temperature using time-of-flight photoconductivity measurement. It is found that the DTP-FLU oligomer is a hole transporting material with a hole mobility of 7.7 × 10?6 cm2/Vs at an applied electric field of 2.9 × 105 V/cm at 298 K. The dependence of hole mobility with applied electric field and temperature is studied in detail by analyzing the experimental results using the Bassler’s Gaussian disorder model and Correlated disorder model. The energetic disorder parameter (σ) = 100 meV, mobility pre-factor (μ∞) = 6.1 × 10?4 cm2/Vs and positional disorder parameter (Σ) = 2.4 were extracted using Gaussian disorder model. The film morphology and photophysical properties of this new oligomer are also studied in detail. 相似文献
883.
K. J. Thomas K. George Thomas T. K. Manojkumar Suresh Das M. V. George 《Journal of Chemical Sciences》1994,106(6):1375-1382
A cyanine chromoionophore1 has been synthesised and its photophysical properties have been investigated. Complexation with alkali metal cations (Li+ and Na+) brings about a significant shift in the absorption and emission spectra to shorter wavelengths, which is accompanied by
an enhancement in the fluorescence quantum yield. These effects can be attributed to the suppression of intramolecular charge
transfer processes of the cyanine dye, brought about by complexation with the metal cations.
Dedicated to Professor C N R Rao on his sixtieth birthday
Contribution No. RRLT-PRU-42 from the Regional Research Laboratory, Trivandrum 相似文献
884.
Lateral connections between adjacent lines of metallization have been developed in order to achieve high density linking for customization in programmable gate arrays and for additive redundancy in restructurable integrated circuits. Links were formed by focusing a pulsed laser between two same-level aluminum lines. The mechanism of link formation appears to be the nucleation of a fissure, induced by the thermal expansion mismatch between the metallization and the surrounding dielectric (SiO2) and passivation layer (Si3N4); molten aluminum fills the crack. Numerical simulation by the finite element method was carried out using a plane strain model. The probable path for the link-forming fissure, as predicted by the model on the premise that the local maximum tensile stress determines cracking, is shown to be consistent with experimental observations. Parametric analyses were performed to gain insights into the linking processes. It is found that damage in the passivation can be avoided by increasing the thickness of the dielectric between the aluminum and the passivation. Reducing the spacing between the metal lines increases the chance of successfully forming the link. Under certain conditions, the linking propensity can also be increased by reducing the metal width. In addition, the link is much easier to form when symmetric laser heating between the two metal lines can be achieved. These findings can be directly applied to improving the design of the laser linking processes and devices 相似文献
885.
M. I. Adamovich M. M. Aggarwal Y. A. Alexandrov N. P. Andreeva Z. V. Anson R. Arora F. A. Avetyan S. K. Badyal E. Basova K. B. Bhalla et al. 《Zeitschrift fur Physik C Particles and Fields》1992,55(2):235-242
The scaling behaviour in the fragmentation regions is investigated for16O-Em interactions from 3.7 to 200A GeV. It is found that in both the projectile- and the target-fragmentation regions, the multiplicity and pseudo-rapidity distributions as well as the two-particle pseudo-rapidity correlations are independent of incident energy. The intermittency indices at 14.6, 60 and 200A GeV are the same within the experimental errors, indicating that the limiting fragmentation hypothesis works with regard to dynamical as well as statistical fluctuations. 相似文献
886.
The problem of calculating the equilibrium properties ofv-dimensional fluid mixture of hardv-spheres is studied. High temperature expansion for the density independent radial distribution function is derived for a
hardv-sphere mixture. The ‘excess’ quantum corrections to the second virial coefficient and the excess free energy are also studied.
Significant features are the large increase in ‘excess’ quantum correction with increasing dimensionality. 相似文献
887.
Andrew J. Lock Ranjan Ganguly Ishwar K. Puri Suresh K. Aggarwal Uday Hegde 《Proceedings of the Combustion Institute》2005,30(1):511-518
While premixed and nonpremixed microgravity flames have been extensively investigated, the corresponding literature regarding partially premixed flames (PPFs) is sparse. We report the first experimental investigation of burner-stabilized microgravity PPFs. Partially premixed flames with multiple reaction zones are established in microgravity on a Wolfhard–Parker slot burner in the 2.2 s drop tower at the NASA Glenn Research Center. Microgravity measurements include flame imaging, and thermocouple and radiometer data. Detailed simulations are also used to provide further insight into the steady and transient response of these flames to variations in g. The flame topology and interactions between the various reaction zones are strongly influenced by gravity. The flames widen substantially in microgravity. During the transition from normal to microgravity, the flame structure experiences a fast change and another relatively slower transient change. The fast response is due to the altered advection as the value of g is reduced, while the slow response is due to the changes in the diffusive fluxes. The radiative heat loss from the flames increases in microgravity. A scaling analysis based on a radiation Damköhler number is able to characterize the radiation heat loss. 相似文献
888.
Moiré deflectometry, based on infinite fringe detection, is a sensitive and advantageous method for the precise measurement of optical parameters. An alternative approach, based on accurate finite-fringe detection moiré deflectometry, is described for the measurement of radius of curvature. An error estimation of the method, supported by experimental verification, is also presented. Extension of the method for the measurement of a long radius of curvature has also been suggested. 相似文献
889.
890.
P. K. Suresh 《International Journal of Theoretical Physics》2004,43(2):425-436
A thermal squeezed state representation of inflaton is constructed for a flat Friedmann–Robertson–Walker (FRW) background metric and the phenomenon of particle creation is examined during the oscillatory phase of inflaton, in the semiclassical theory of gravity. An approximate solution to the semiclassical Einstein equation is obtained in thermal squeezed state formalism perturbatively and is found obey the same power-law expansion as that of classical Einstein equation. In addition to that the solution shows oscillatory in nature except on a particular condition. It is also noted that, the coherently oscillating nonclassical inflaton, in thermal squeezed vacuum state, thermal squeezed state, and thermal coherent state, suffers particle production and the created particles exhibit oscillatory behavior. The present study can account for the postinflation particle creation due to thermal and quantum effects of inflation in a flat FRW universe. 相似文献