We prove a fixed point result for nonlinear operators, acting on some classes of functions with values in a dq-metric space, and show some applications of it. The result has been motivated by some issues arising in Ulam stability. We use a restricted form of a contraction condition. 相似文献
A facile metal catalyst free route to synthesize boron doped (0.6%–1.0%) carbon nanotubes via ceramic nanowires in which the formation of the nanowires (probably serving as templates), the carbon nanotubes and their doping all occur unanimously in the reaction, is presented.
The synthesis of the title compound derived from the tetralin system is reported. On the basis of PMR and MS spectra the possibility of the formation of an isomeric bispirane is discussed. 相似文献
It is shown that a metric continuum is a dendrite if and only if for every compact space (continuum) and for every light confluent mapping such that there is a copy of in for which the restriction is a homeomorphism. As a corollary it follows that only dendrites have the lifting property with respect to light confluent mappings. Other classes of mappings are also discussed. This is a continuation of a previous study by the authors (2000), where open mappings were considered.
The multistage control of a deterministic and stochastic system in a fuzzy environment is considered. The fuzzy environment is meant as fuzzy constraints imposed on subsequent controls and a fuzzy goal to be attained. The fuzzy decision is assumed to be the intersection of fuzzy constraints and a fuzzy goal. The problem is to find a maximizing decision. The termination time is given as a specified fuzzy set in the space of control stages. For solving the problem, the dynamic programming is applied. 相似文献
We introduce the class of dense relations on a set X
and prove that for any finitary or infinitary dense relation
on X, the relational system (X,) is determined up
to semi-isomorphism by the monoid End(X,) of endomorphisms of (X,). In the case of binary relations, a semi-isomorphism is
an isomorphism or an anti-isomorphism. 相似文献
This work contains the results of studies on the influence of newly synthesized lysosomotropic substances (lysosomotropes) on human erythrocytes. Six homologous series of the compounds differing in the alkyl chain length and counterions were studied. They were found to hemolyse erythrocytes and to change their osmotic resistance. The observed hemolytic effects were dependent both on the compounds structure (polar head dimension and alkyl chain length of compound) and its form (the kind of the counterion). In parallel, the influence of lysosomotropes on fluidity of the erythrocyte membrane was studied. Three different fluorescent probes were used; 1,6-diphenyl-1,3,5-hexatriene (DPH), 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene, p-toluenesulfonate (TMA-DPH) and 6-dodecanoyl-2-dimethylaminonaphthalene (laurdan). Their anisotropy (DPH and TMA-DPH) or general polarization (laurdan) values after incorporation into ghost erythrocyte membranes were measured. The results obtained show that fluidity changes accompanied the effects observed in hemolytic experiments both quantitatively and qualitatively. 相似文献