German to English Tech/Engineering Electronics / Elect Eng bushing/connection

This appears in a patent, in which a bushing is being defined. The term, and its opposite, appear in the following definitions:

Bei den aus der Praxis bekannten Durchführungen bzw. Verbindungen unterscheidet man zwischen den sog. **„angepassten“ Verbindungen** und den „nicht-angepassten“ Verbindungen. Bei den **angepassten Verbindungen** werden Materialien verwendet, deren thermische Ausdehnungskoeffizienten sich nicht oder nur gering voneinander unterscheiden. Dies führt dazu, dass die Glas-Metall-Verbindung nach dem Abkühlen keine oder kaum innere Spannungen aufweist. ...
Bei **nicht-angepassten** Verbindungen liegen unterschiedliche thermische Ausdehnungskoeffizienten der Materialien vor.

I understand that the "angepassten" connections are made from materials that have identical thermal expansion coefficients, or whose coefficients differ only slightly. And that "nicht-angepassten" connections are made from materials that have different thermal expansion coefficients.
However, I can't determine if this identifies fitted/non fitted, adapted/non-adapted, matched/unmatched connections or what.

The "so-called" seems to imply that this term is common; however I cannot find this definition in use anywhere else. While it seems important that the materials have identical/different thermal expansion coefficients for various applications, I haven't found anything naming the connection based on this criterion.

Many thanks in advance.