The phrase "a main problem of" is correct and usable in written English.
It can be used when discussing a significant issue or challenge related to a specific topic or subject matter.
Example: "One main problem of the current education system is the lack of resources for underprivileged schools."
Alternatives: "a primary issue with" or "a key challenge of".
How to build a synthetical sampling subset of data representing a larger one becomes a main problem of sampling experiments.
A main problem of clinical phenotyping is that the definition is often biased, as mostly only the most dominant disease feature is used for classification [5].
At the same time, a main problem of master acquisition is that a highly precise synchronization with narrow pulse signal costs long time to be achieved.
A main problem of studies based on self-administrated questionnaires is to correctly diagnose patients with the co-existence of two or more headaches, usually migraine and tension-type headache.
A major advantage of video-based face recognition is that a set of images of the same subject can be captured in a video sequence, while a main problem of video-based face recognition lies in the low images quality in video frames.
The Seattle Times Kay McFadden also found a main problem of the show in the characters, believing that the pilot was more focused on plot development than it was on character development.
A main problem is the lack of a discernible end to the spreading protests.
A lack of existing "generic" industry-sector-specific concepts for service description is a main problem that the potential of e-commerce is not utilized for product-services.
A main problem is the absence of a 'gold standard' against which to compare indicators.
A main problem with heterologous expression of xylose transporters is inefficient targeting to the plasma membrane.
A main problem has been the assumption of thermodynamic equilibrium for what is a metastable system.
