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51.
The scattering theory for the Klein Gordon equation, with time-dependent potential and in a non-static space-time, is considered.
Using the Klein Gordon equation formulated in the Hubert spaceL
2(R
3) and the Einstein’s relativistic equation in the spaceL
2(R
3, dx) and establishing the equivalence of the vacuum states of their linearized forms in the Hubert spaceL
2(R
3) with the help of unique symmetric symplectic operator, the time evolution unitary operatorU(t) has been fixed for the Klein Gordon equation, incorporating either the positive or negative frequencies, in the infinite
dimensional Hubert spaceL
2(R
3). 相似文献
52.
53.
Tabu search is a meta-heuristic problem solving technique that, when applied carefully, provides near optimal solutions in a very short time. In this paper, we have described the use of tabu search for solving problems related to very large scale integrated (VLSI) circuit design automation. Specifically, we have demonstrated the use for VLSI circuit partitioning and placement. We present a tabu search based circuit bi-partitioning technique that partitions circuits with the goal of minimizing the size of the cutset between the partitions. Then, we use tabu search techniques along with force directed placement techniques to accomplish the physical placement of VLSI circuits on regular two-dimensional arrays with the goal of minimizing the placement time. We use empirical data from partitioning and placement of benchmark circuits to test our techniques. Our methods show improvement when compared to partitioning techniques from the literature and commercially available placement tools. Relative to the literature, our tabu search bi-partitioning technique improves on the best known minimum cuts for several benchmark circuits. Relative to commercially available computer aided design tools, our tabu search based placement approach shows dramatic (20×) speedup in execution time without negative impact on the quality of the solution. 相似文献
54.
55.
Norm inequalities for partitioned operators and an application 总被引:6,自引:0,他引:6
56.
57Fe Mössbauer spectroscopy is used to study the interactions, geometry, and the coordination characteristics of the Fe-complexes of biopolymers such as chitosan, glucosamine, and chondritin sulfate. In addition, a computational effort is undertaken for predicting the geometries and energies of the metal complexes by the Density Functional Theory (DFT) methods as implemented in the Gaussian 2003 quantum mechanical program. Both experimental and computational results suggest that the structure of the metal complexes resemble closely the structure of the active sites of metalloenzymes in 2+ or 3+ oxidation states and is at least tetracoordinated and can possibly have six ligands. 相似文献
57.
Salwa Meredith Hashim Abdul Rahman Mohamed Subhash Bhatia 《Journal of Sol-Gel Science and Technology》2011,59(3):505-512
Perovskite-type La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF6428) thin-film membrane prepared by modified Pechini sol–gel process, was successfully deposited on porous support
of similar composition using dip-coating method. Fine grain and crack-free film with perovskite structure was obtained at
sintering temperature of 800 °C and dwelling time of 60 min. The cross-sectional image indicated that LSCF6428 thin-film membrane
coated on the porous support showed excellent adhesion to the support with uniform thickness. The minimum dense layer thickness
obtained by dip-coating method was around 0.5 μm. It was found that the oxygen permeability of the supported thin film was
lower than that of the perovskite support, which indicated that the pores of the support were reduced by thin-film deposition
on the support surface. The reduction in the pore size led to the more selective permeation mechanism contributes to the overall
permeation. Successful deposition of LSCF6428 thin-film membrane on porous support can be considered as a promising technique
for the preparation of oxygen separation membrane. 相似文献
58.
59.
In this paper generalized type-I, generalized quasi type-I, generalized pseudo type-I and other related functions over cones
are defined for a vector minimization problem. Sufficient optimality conditions are studied for this problem using Clarke’s
generalized gradients. A Mond-Weir type dual is formulated and weak and strong duality results are established. 相似文献
60.