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61.
In this paper we provide an error bound estimate and an implicit multifunction theorem in terms of smooth subdifferentials and abstract subdifferentials. Then, we derive a subdifferential calculus and Fritz–John type necessary optimality conditions for constrained minimization problems. 相似文献
62.
63.
E. A. Klop B. J. Lommerts J. Veurink J. Aerts R. R. Van Puijenbroek 《Journal of Polymer Science.Polymer Physics》1995,33(2):315-326
Differential scanning calorimetry and high temperature x-ray diffraction were used to study the perfectly alternating copolymer of ethene and carbon monoxide (polyketone; POKC2). It was found that oriented POK-C2 fibers show a crystalline phase transition at a temperature between 110–125°C with a 10% change in crystalline density. At this temperature, the crystal structure reported recently (POK-α) is transformed to a crystal structure that was reported in the past for room temperature imperfectly alternating polyketone. The latter structure will be designated as POK-β. The influence of chain defects on the crystal structure was studied by synthesizing terpolymers (POK-C2/C3), in which small amounts of propylene-CO units are incorporated into the polymer backbone. The resulting terpolymers differ from the copolymer by the presence of methyl groups randomly distributed along the polyketone backbone chain. Evidence is presented that indicates that the methyl groups are built into the crystal lattice as defects. With more than 5 mole-% propene the terpolymer fibers crystallize exclusively in the β-modification. Below this level the α/β ratio (at room temperature) increases with decreasing amounts of propene. Both as-synthesized and as-spun POK-C2 were found to consist of both POK-α and POK-β; the α/β ratio depends on the method of preparation. Because the drawn POK-C2 fibers studied here consist exclusively of POK-α, the process of spinning and drawing leads to the transformation of unoriented β-rich material into oriented POK-α. © 1995 John Wiley & Sons, Inc. 相似文献
64.
W.-H. Steeb M. A. Van Wyk R. Stoop 《International Journal of Theoretical Physics》1998,37(10):2653-2655
We describe a one-dimensional chaotic map wherethe Liapunov exponent is a smooth function of a controlparameter. 相似文献
65.
66.
The generator coordinate approximation is a non-adiabatic theory of molecular systems. Its fundamental outlines were developed during the 1970's. A further analysis and first applications were published during the 1980's. In this paper, we review the present status of the theory. 相似文献
67.
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69.
For a real Enriques surface Y we prove that every homology class in H1(Y (R), Z/2) can be represented by a real algebraic curve if and only if all connected components of Y(R) are orientable. Furthermore, we give a characterization of real Enriques surfaces which are Galois-Maximal and/or Z-Galois-Maximal and we determine the Brauer group of any real Enriques surface Y. 相似文献
70.
In this paper, we analyze a discrete-time preemptive repeat priority queue with resampling. High-priority packets have preemptive
repeat priority, and interrupted low-priority packets are subjected to independent retransmission attempts. Both classes contain
packets with generally distributed transmission times. We show that the use of generating functions is beneficial for analyzing
the system contents and packet delay of both classes. The influence of the priority scheduling on the performance measures
is illustrated by some numerical examples.
This work has been supported by the Interuniversity Attraction Poles Programme–Belgian Science Policy. 相似文献