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1.
Several variations of two-dimensional (workers x jobs) and three-dimensional (workers x jobs x machines) time- as well as cost-minimizing assignment problems, which arise owing to (i) precedence relations of some form among the jobs or (ii) capacity restrictions on workers/machines imposed by the requirement that the surplus resources have to be fully employed, have been considered in the literature. In this paper, an algorithm is presented for time-cost trade-off analysis which is applicable to any general pair of such constrained problems. The algorithm is also illustrated by a numerical example. 相似文献
2.
C. V. Yelamaggad Manoj Mathews Uma Hiremath Geetha Nair D. S. Shankar Rao S. Krishna Prasad 《Liquid crystals》2003,30(8):899-908
A series of symmetrical dimers consisting of salicylaldimine moieties connected by flexible alkylene central spacer via ether linkages has been synthesized. In order to validate the empirical rule suggested by Date et al. to account for the smectic behaviour of such dimers, the chain length of the terminal alkoxy chain has been kept constant (C8) while the number of methylene units in the central spacer was varied from C3 to C11. Another aim of the present investigation was to understand structure-property relationship in these dimers in which the salicylaldimine mesogenic segment has been used for the first time in dimers. The mesomorphic behaviour of these dimers was evaluated using optical microscopy and differential scanning calorimetry and the structure of some of the mesophases has been further investigated with the help of X-ray diffraction. Our studies reveal that the dimers consisting of 3 to 8 methylene units in the flexible spacer show only smectic (smectic C and smectic A) phases. For the dimers containing 4, 6 and 8 methylene units in the central spacer, a unique filament growth pattern has been observed in the smectic A phase while cooling from the isotropic phase. The dimers containing of C9 to C11 methylene groups exhibit the nematic phase in addition to smectic modifications. This observation indicates that when the terminal chains are shorter than the spacer, the tendency to form smectic phases is not fully extinguished but is perhaps reduced. 相似文献
3.
Based on the matrix-analytic approach to fluid flows initiated by Ramaswami, we develop an efficient time dependent analysis
for a general Markov modulated fluid flow model with a finite buffer and an arbitrary initial fluid level at time 0. We also
apply this to an insurance risk model with a dividend barrier and a general Markovian arrival process of claims with possible
dependencies in successive inter-claim intervals and in claim sizes. We demonstrate the implementability and accuracy of our
algorithms through a set of numerical examples that could also serve as test cases for comparing other solution approaches.
相似文献
4.
Geetha Ramaswami 《BIT Numerical Mathematics》1997,37(2):465-471
In this paper, we derive a one-parameter family of symplectic Runge-Kutta-Nyström methods of order 2s-1 and a two-parameter family of symplectic Runge-Kutta methods of order 2s-2. 相似文献
5.
6.
Charge distribution study in the alpha-particle induced fission of232Th+ effect of excitation energy
Ramaswami A. Srivastava B. K. Sahakundu S. M. Manohar S. B. Prakash Satya Ramaniah M. V. 《Journal of Radioanalytical and Nuclear Chemistry》1986,102(2):499-506
The fractional cumulative yields of135I,138Xe and140Ba in the particle (30 MeV) induced fission of232Th have been determined following the growth and decay of135gXe,138gCs and140La, respectively, employing high resolution gamma ray spectroscopy. The fractional cumulative yield values are 0.766±0.02, 0.813±0.03 and 0.991±0.004, respectively. The analysis of the data indicates a broader width of charge distribution () compared to the normally observed =0.56±0.06 for thermal neutron fission of235U. 相似文献
7.
A. Ramaswami S. S. Rattan P. C. Kalsi S. P. Dange 《Journal of Radioanalytical and Nuclear Chemistry》2003,256(2):353-355
The absolute fission yields of twenty seven fission products were determined in the fast neutron induced fission of 233U, employing track etch in combination with gamma-ray spectrometry. The total number of fissions was measured by registering the fission tracks on a small strip of lexan, a solid state track detector. The fission products were analysed by gamma-ray spectrometry. The measured yield values were compared to the ENDF/B-VI compilation and show a good agreement. 相似文献
8.
Synthesis and rearrangement of bicyclo(4.3.0) - 2β - hydroxy - 2α - vinyl - 1β - methyl - 8 - oxo - Δ6 - nonene was observed to yield a transannular reaction product tricycio - (6.3.0.01,8) - 2 - methyl - 8α - hydroxy - 4 - oxo - Δ2 - undecene 16. Spectral evidence supports the assigned structure. 相似文献
9.
A. Ramaswami G. K. Gubbi R. J. Singh Satya Prakash 《Journal of Radioanalytical and Nuclear Chemistry》1988,125(1):85-89
Cumulative yields of short-lived/barium isotopes139, 141, 142Ba have been determined in the spontaneous fission of252Cf, using fast radiochemical separation and gamma-ray spectrometry.142Ba yield is reported for the first time. The measured cumulative yields are converted to chain yields, assuming normal charge distribution systematics for comparision with the literature data. 相似文献
10.