Geometric programming (GP) provides a power tool for solving a variety of optimization problems. ... more Geometric programming (GP) provides a power tool for solving a variety of optimization problems. In the real world, many applications of geometric programming (GP) are engineering design problems in which some of the problem parameters are estimating of actual values. This paper develops a solution procedure to solve nonlinear programming problems using GP technique by splitting the cost coefficients, constraint coefficients and exponents with the help of binary numbers. The equivalent mathematical programming problems are formulated to find their corresponding value of the objective function based on the duality theorem. The ability of calculating the cost coefficients, constraint coefficients and exponents developed in this paper might help lead to more realistic modeling efforts in engineering design areas. Standard nonlinear programming software has been used to solve the proposed optimization problem. Two numerical examples are presented to illustrate the method.
Although plasma torches have been commercially available for about 50 years, areas such as plasma... more Although plasma torches have been commercially available for about 50 years, areas such as plasma gun design, process efficiency, reproducibility, plasma stability, torch lives etc. have remained mostly unattended. Recent torch developments have been focusing on the basic understanding of the plasma column and its dynamics inside the plasma torch, the interaction of plasma jet and the powders, the interaction
Zeitschrift f�r Physik D Atoms, Molecules and Clusters, 1993
Doubly excited triplet states have been obtained for the first four members of helium isoelectron... more Doubly excited triplet states have been obtained for the first four members of helium isoelectronic sequence for the transitions Nsnp:3 P 0, Nsnd:3 D e and Npnd:3 F 0 for N=2, 3, 4, n≧ N, 4 using a newly developed formalism based on time dependent perturbation theory. The doubly excited states have been identified as resonances in the oscillations of the two electron charge cloud and are obtained from a study of the behaviour of an appropriately constructed linearised variational functional with respect to externally impressed frequency. A correlated description of the orbitals in terms of product basis sets has been used. Many of the results are new and agreement with the experimental and theoretical data, whenever available, is good. Analytic representations of the doubly excited states have been obtained. These are used to calculate the Coulomb repulsion between the electron pair and may be very useful for calculating other physical properties of the system connected with transitions.
A numerical analysis is presented for the response of a solar cell illuminated by a nonuniform li... more A numerical analysis is presented for the response of a solar cell illuminated by a nonuniform light beam. The photogenerated carrier density in the illuminated zone is found by solving two-dimensional diffusion equations. Analytical curves are given for the variations of short-circuit current with the width of the beam exposure for various levels of skin-layer thickness. Curves are also given for the short-circuit current as a function of beam width for a source having a Gaussian intensity distribution and spot size as a parameter. The analytical results are compared to experimental data for a He-Ne laser beam in the TEM(00) mode and a silicon solar cell. Bibtex entry for this abstract Preferred format for this abstract (see Preferences) Find Similar Abstracts: Use: Authors Title Keywords (in text query field) Abstract Text Return: Query Results Return items starting with number Query Form Database: Astronomy Physics arXiv e-prints
... 1975). MHD Power Generation, Selected Problems of Combustion MHD Dastidar, P. R., Rohatgi, V.... more ... 1975). MHD Power Generation, Selected Problems of Combustion MHD Dastidar, P. R., Rohatgi, V. K., Seshadri, S. N., Sridharan, S., Malghan, VR and Balasubramanian, V. (1985). 'Indian MHD program, an Das. A. K. (1980). ...
Among the different mechanisms of heat transfer during nucleate pool boiling, evaporation from th... more Among the different mechanisms of heat transfer during nucleate pool boiling, evaporation from the micro layer, evaporation from the macro layer, and transient heat transfer from the fluid mass above the macro layer play very crucial roles. Based on these three mechanisms, a model made earlier by the authors can predict the pool boiling heat transfer of water from flat
An infinite interface of randomly distributed contacts is modeled as a finite square region with ... more An infinite interface of randomly distributed contacts is modeled as a finite square region with randomly placed contacts inside it. The contacts outside the region are treated as continuum of contacts. The continuum approximation allows for an interaction between the contacts within the square and those outside it. An analytical solution is obtained for the temperature field, and the contact
Geometric programming (GP) provides a power tool for solving a variety of optimization problems. ... more Geometric programming (GP) provides a power tool for solving a variety of optimization problems. In the real world, many applications of geometric programming (GP) are engineering design problems in which some of the problem parameters are estimating of actual values. This paper develops a solution procedure to solve nonlinear programming problems using GP technique by splitting the cost coefficients, constraint coefficients and exponents with the help of binary numbers. The equivalent mathematical programming problems are formulated to find their corresponding value of the objective function based on the duality theorem. The ability of calculating the cost coefficients, constraint coefficients and exponents developed in this paper might help lead to more realistic modeling efforts in engineering design areas. Standard nonlinear programming software has been used to solve the proposed optimization problem. Two numerical examples are presented to illustrate the method.
Although plasma torches have been commercially available for about 50 years, areas such as plasma... more Although plasma torches have been commercially available for about 50 years, areas such as plasma gun design, process efficiency, reproducibility, plasma stability, torch lives etc. have remained mostly unattended. Recent torch developments have been focusing on the basic understanding of the plasma column and its dynamics inside the plasma torch, the interaction of plasma jet and the powders, the interaction
Zeitschrift f�r Physik D Atoms, Molecules and Clusters, 1993
Doubly excited triplet states have been obtained for the first four members of helium isoelectron... more Doubly excited triplet states have been obtained for the first four members of helium isoelectronic sequence for the transitions Nsnp:3 P 0, Nsnd:3 D e and Npnd:3 F 0 for N=2, 3, 4, n≧ N, 4 using a newly developed formalism based on time dependent perturbation theory. The doubly excited states have been identified as resonances in the oscillations of the two electron charge cloud and are obtained from a study of the behaviour of an appropriately constructed linearised variational functional with respect to externally impressed frequency. A correlated description of the orbitals in terms of product basis sets has been used. Many of the results are new and agreement with the experimental and theoretical data, whenever available, is good. Analytic representations of the doubly excited states have been obtained. These are used to calculate the Coulomb repulsion between the electron pair and may be very useful for calculating other physical properties of the system connected with transitions.
A numerical analysis is presented for the response of a solar cell illuminated by a nonuniform li... more A numerical analysis is presented for the response of a solar cell illuminated by a nonuniform light beam. The photogenerated carrier density in the illuminated zone is found by solving two-dimensional diffusion equations. Analytical curves are given for the variations of short-circuit current with the width of the beam exposure for various levels of skin-layer thickness. Curves are also given for the short-circuit current as a function of beam width for a source having a Gaussian intensity distribution and spot size as a parameter. The analytical results are compared to experimental data for a He-Ne laser beam in the TEM(00) mode and a silicon solar cell. Bibtex entry for this abstract Preferred format for this abstract (see Preferences) Find Similar Abstracts: Use: Authors Title Keywords (in text query field) Abstract Text Return: Query Results Return items starting with number Query Form Database: Astronomy Physics arXiv e-prints
... 1975). MHD Power Generation, Selected Problems of Combustion MHD Dastidar, P. R., Rohatgi, V.... more ... 1975). MHD Power Generation, Selected Problems of Combustion MHD Dastidar, P. R., Rohatgi, V. K., Seshadri, S. N., Sridharan, S., Malghan, VR and Balasubramanian, V. (1985). 'Indian MHD program, an Das. A. K. (1980). ...
Among the different mechanisms of heat transfer during nucleate pool boiling, evaporation from th... more Among the different mechanisms of heat transfer during nucleate pool boiling, evaporation from the micro layer, evaporation from the macro layer, and transient heat transfer from the fluid mass above the macro layer play very crucial roles. Based on these three mechanisms, a model made earlier by the authors can predict the pool boiling heat transfer of water from flat
An infinite interface of randomly distributed contacts is modeled as a finite square region with ... more An infinite interface of randomly distributed contacts is modeled as a finite square region with randomly placed contacts inside it. The contacts outside the region are treated as continuum of contacts. The continuum approximation allows for an interaction between the contacts within the square and those outside it. An analytical solution is obtained for the temperature field, and the contact
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