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21.
Journal of Optimization Theory and Applications - Recent advancements in the sensor industry, smart metering systems and communication technology have led to interesting electricity consumption...  相似文献   
22.
We study the relationship between the tight closure of an ideal and the sum of all ideals in its linkage class I thank Mel Hochster and Craig Huneke for their support and encouragement and for many helpful discussions.The author was partially supported by the NSF.  相似文献   
23.
Between the most mature interdisciplinary areas, computational fluid dynamics (CFD) comes recently into focus. In the same time, it becomes more and more difficult to contribute fundamental research to it. However, although it remains unpredictable how CFD develops, it is part of what makes it an exciting and attractive discipline.This paper aims to exhibit some part of recent work in CFD. It concerns the qualitative approach of the turbulent behaviour of a mixing flow in an excitable media. Studying a mixing for a flow implies the analysis of successive stretching and folding phenomena for its particles, the influence of parameters and initial conditions. In the previous works, the study of the 3D non-periodic models exhibited a quite complicated behaviour. In agreement with experiments, there were involved some significant events, the so-called “rare events”. The variation of parameters had a great influence on the length and surface deformations. The experiments were realized with a special vortex installation, it was used a well-known aquatic algae as biologic material, and the water as basic fluid.In the paper there are presented some features of a qualitative comparative analysis of the model associated to the vortex flow technology. In the computational analysis there were used the fast analysis tools of MAPLE11 soft, in order to check the “rare events” and to complete the statistical analysis of the behaviour of the model.  相似文献   
24.
In this paper, we extend some results of D.Dolzan on finite rings to profinite rings, a complete classification of profinite commutative rings with a monothetic group of units is given. We also prove the metrizability of commutative profinite rings with monothetic group of units and without nonzero Boolean ideals. Using a property of Mersenne numbers, we construct a family of power 2ℵ0 commutative non-isomorphic profinite semiprimitive rings with monothetic group of units.  相似文献   
25.
In this paper, we present sufficient conditions for the existence of Henig efficient solutions, superefficient solutions and Henig globally efficient solutions of a vector equilibrium problem in topological vector spaces, using a well-known separation theorem in infinite dimensional spaces. As an application, using a scalarization technique, existence results for proper efficient solutions of generalized vector variational inequalities are given.  相似文献   
26.
27.
A recently developed ultrasound technique is evaluated by measuring the behavior of a cavitation bubble that is induced in water by a femtosecond laser pulse. The passive acoustic emission during optical breakdown is used to estimate the location of the cavitation bubble's origin. In turn, the position of the bubble wall is defined based on the active ultrasonic pulse-echo signal. The results suggest that the developed ultrasound technique can be used for quantitative measurements of femtosecond laser-induced microbubbles.  相似文献   
28.
Correlations involving bond lengths and bond angles in the molecular structure of the Cu4OCl6(4-Mepy)4 complex (4-Mepy = 4-methylpyridine) with four symmetrically independent molecules present in the unit cell showed that the donor-acceptor behavior involving the π-back donation into the pyridine rings of the 4-Mepy ligands is most effectively stimulated by a suitable orientation of the pyridine rings in the trigonal bipyramidal geometry. The pyridine ring planes are almost in parallel orientation with one of the three Cu-Cl bonds. The bond lengths of these Cu-Cl bonds are in a significant linear correlation with the Cu-N bond lengths and the bonds lengths of the pyridine rings. The pyridine rings orientation is affected by distortion of the trigonal bipyramidal geometry to tetragonal pyramidal coordination, by out-of plane pyridine rings deviation and in-plane pyridine rings tilting, by puckering of the pyridine rings and by the effects of the methyl groups. The pyridine rings in at least seven of the sixteen trigonal bipyramidal coordinations exhibit an orientation supporting the π-back bonding between the Cu(II) atoms and the pyridine rings.  相似文献   
29.
Resonance non-positone and non-isotone problems for first order differential systems subjected to non-local boundary conditions are reduced to the non-resonance positone and isotone case by changes of variables. This allows us to prove the existence of multiple positive solutions. The theory is illustrated by two examples for which three positive numerical solutions are obtained using the Mathematica shooting program.  相似文献   
30.
Liquid–liquid equilibria (LLE) for the ternary system {hexane + benzene + 1-ethyl-3-methylimidazolium ethylsulfate ([emim]C2H5SO4)} have been measured at the temperatures (298.2, 313.2 and 328.2) K and atmospheric pressure. The reliability of the experimental data was tested using the Othmer–Tobias correlation. For the extractive effectiveness of the solvent, the distribution ratio and separation factor curves were plotted and compared with those of sulfolane. In addition, the LLE data were also correlated with UNIQUAC and NRTL models in a satisfactory manner.  相似文献   
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