The phrase "a set of existing" is correct and usable in written English.
It can be used when referring to a collection or group of items, concepts, or conditions that are already in place or available.
Example: "The researchers analyzed a set of existing data to draw their conclusions about the study."
Alternatives: "a collection of current" or "a group of available".
"Most business processes are about making choices from a set of existing alternatives.
The approach is demonstrated with respect to a set of existing EIMs.
The researchers began by identifying a set of existing Wikibooks that can act as a training data set.
Similarly to software product lines, language product lines are often built from a set of existing DSL variants.
In order to test the proposed algorithm, we compare it with a set of existing algorithms on several problem instances.
To this aim, the impact of the extension from mechatronic to Cyber-Physical Systems on their design is examined through a set of existing related modelling techniques.
As downtown has produced new office towers and significant projects – many of them east of Main Street – it "put the pressure market-wise on a huge set of existing Class A properties downtown to refresh and reset," he observes.
We evaluate the performance of a representative set of existing methods for predicting SDPs from a MSA divided into specificity groups against a simple, baseline method.
To support this transition, we created ToxRefDB to capture a rich set of existing in vivo laboratory animal toxicity data on a group of environmentally relevant, well-studied chemicals.
This approach leverages a given set of existing matching between two models and upgrades those matching when a new version of a target model is released.
Complex simulation programs in science and engineering are often built up from a diverse set of existing applications.
