English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

For graphic representation of the projective creations, such as the quadrics  (II degree surfaces) in projective, general collinear spaces, it is necessary  to firstly determine the characteristic parameters, such as: vanishing  planes, axes and centers of space. An absolute conic of a space is an  imaginary conic, residing in the infinitely distant plane of that space. The  common elements of the absolute conic and infinitely distant conic of a  quadric in the infinitely distant plane of that space are the autopolar  triangle and two double straight lines which are always real and it is  necessary to use the common elements of their associated pair of conics in  the vanishing plane of the associated space. The quadric axes are passing  through the apices of the autopolar triangle, and they are important for  graphic representation of the quadrics. In order to map a sphere in the first  space into the triaxial ellipsoid in the second space, it is necessary to  select a sphere so that its center is not on the axis of that space and that  it intersects the vanishing plane of the second space along the imaginary  circumference, which is in general position with the figure of the absolute  conic of the second space (the associated pair of conics in the vanishing  plane)

Graphic representation of a triaxial ellipsoid by means of a sphere in general collinear spaces