R&D competition versus R&D cooperation in oligopolistic markets with evolving structure

R&D Competition versus R&D Cooperation in Oligopolistic Markets with Evolving Structure

This paper considers investment behavior of duopolistic firms subject to technological progress. It is assumed that initially both firms offer a homogeneous product, but after a stochastic waiting time they are able to realize a product innovation. Production capacities of both firms are product specific. It is shown that firms anticipate a future product innovation by under-investing (if the n...

RD-flatness and RD-injectivity

It is proved that every commutative ring whose RD-injective modules are Σ-RD-injective is the product of a pure semi-simple ring and a finite ring. A complete characterization of commutative rings for which each artinian (respectively simple) module is RD-injective, is given. These results can be obtained by using the properties of RD-flat modules and RD-coflat modules which are respectively th...

Early markers of retinal degeneration in rd/rd mice.

PURPOSE In the rd/rd mouse, the cell death of rod photoreceptors has been correlated to abnormal levels of the cyclic nucleotide cGMP within photoreceptors. Given that cGMP is required for opening of the cationic channels, there is the possibility that a high cGMP concentration would maintain these channels open, at a high energy cost for the retina. METHODS We investigated whether cation cha...

Homeomorphic meshes in Rd

Apollonius Solutions in Rd

Voronoi and related diagrams have technological applications, for example, in motion planning and surface reconstruction, and also find significant use in materials science, molecular biology, and crystallography. Apollonius diagrams arguably provide the most natural division of space for many materials and technology problems, but compared to Voronoi and power diagrams, their use has been limi...