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61.
This communication points out a couple of early publications on the power-of-two scheduling scheme that has been consistently ignored by researchers in the past. 相似文献
62.
This paper deals with the problem of determining economic maintenance frequency for a group of machines. The operating cost for each machine is assumed to increase with time since the last maintenance work carried out on the machine. The cost of carrying out maintenance work is known and assumed constant. A fixed cost is incurred whenever maintenance work is carried out, and this fixed cost is assumed to be independent of the number of machines on which maintenance work is carried out. The total cost of the system is given by the sum of maintenance and operating costs for all the machines. A heuristic method is proposed for determining the economic maintenance frequency of each machine. An example is given to illustrate the method. 相似文献
63.
64.
65.
Quantum chromodynamics based isovector isoscolar particle mixing arising out of isospin violating quark mass differences has been used to construct a new charge-symmetry breaking Λ-N interaction element. It appears that vector meson exchanges between N and a physical Λ rather than pseudoscalar exchanges provide the largest contribution to explain the binding energy difference between the mirror hyper-nuclei ΛHe4 and ΛH4. Prediction of the model to Λn and Λp scattering lengths have been compared with those obtained from the combined analysis of ΛN scattering and s-shell hyperfragment data. We find satisfactory agreement of our results. 相似文献
66.
67.
Prasanna K. Mishra S. I. Hosain I. C. Goyal Anurag Sharma 《Optical and Quantum Electronics》1984,16(4):287-296
A scalar variational analysis for the fundamental mode of a graded-core, W-type fibre based on single and two parameter trial fields has been presented. Comparison with the exact numerical results shows that the two parameter trial field estimates the propagation characteristics accurately.On study leave from Physics Department, G.M. College, Sambalpur-768004, India. 相似文献
68.
Abstract— From the theoretical analysis of the time variation of the change in absorbance of chicken iodopsin solution (at—195°C), the formation of a new intermediate during bleaching has been suggested. 相似文献
69.
The Bi2Sr2CaCu2O8 system is viewed as an archetypal of superconductors modelled as Josephson coupled CuO2 bilayers. The isothermal and temperature dependent DC and AC magnetization measurements forH‖c in a single crystal of Bi2212 have been performed. Qualitative changes are observed to occur over a narrow range of temperature
values before reaching the superconducting-normal transition. The observed behaviour can be ascribed to the rapid variation
in the strength of the coupling between the superconducting CuO2 planes (i.e., bilayers in the case of Bi2212). Strongly coupled planes behave like a 3D superconductor, whereas weakly coupled
planes have a two component response attributable to 2D planes and interplanar couplings. We believe that this paper is a
plethora of new findings. Our observations imply that resistivity across the planes becomes zero earlier than that within
the planes. A new line (designated asH
2D(T)) above which the change in the electromagnetic response is dominated by quasi 2D-planes has been determined for the first
time. This paper also contains the first observation of Differential Diamagnetic Effect (DDE) in the In-phase AC susceptibility
data which signals the onset (atT
2D(H)) of dominance of response from 2D-planes. In addition to a host of interesting thermomagnetic history effects which are
a consequence of interplay between the diamagnetic responses from the two components, a comparison of irreversibility lines
(of the 3D state) determined by different methods on the same specimen of a HTSC is also being presented for the first time.
We have come across Paramagnetic Meissner Effect (PME), first recognized in ceramic samples of Bi2212, in the temperature
region of dimensional crossover in our single crystal sample, whichinter-alia confirms our labelling of the two component behaviour. A schematic phase diagram summarizing the various transformations
that can occur nearT
c in the electromagnetic response of an anisotropic layered system has been drawn. 相似文献
70.
In the present communication an analysis of interionic potentials in fourteen chalcogenide crystals has been performed. This interionic potential has been used to predict the values of cohesive energy, isothermal bulk modulus and the pressure derivatives of bulk modulus in the solids under study. The many body interaction (MBI) effects have been taken into account within the framework of Hafemeister Zarht potential. Instead of using BM potential the Hafemeister-Zarht (HZ) type short range overlap potential has been considered between nearest as well as between next nearest neighbour ions. The short-range interactions, effective up to second neighbours are treated by considering the hardness parameter as an ionic property. The hardness parameter ρij is evaluated using the data on overlap integrals. The results achieved in the present study are generally in good agreement with available experimental data. Values of cohesive energy, bulk modulus and its pressure derivatives calculated by previous investigators have also been shown for the sake of comparison. 相似文献