Husserl's ideas on formal ontology were developed especially by his Polish student Roman Ingarden in his Controversy over the Existence of the World.
Also known as continuants, or in some cases as "substance", endurants are those entities that can be observed-perceived as a complete concept, at no matter which given snapshot of time.
Most formal upper-level ontologies recognize qualities, attributes, tropes, or something related, although the exact classification may differ.
Some see qualities and the values they can assume (sometimes called quale) as a separate hierarchy besides endurants and perdurants (example: DOLCE).
As a quality, it is said to inhere in independent endurant entities (see above), as such, it cannot exist without a bearer (in the case the arm).
The divergence of the underlying meaning of word descriptions and terms within different information sources is a well known obstacle for direct approaches to data integration and mapping.
Where two or more external information sources map to one and the same formal ontology concept a crossmapping/translation is achieved, as you know that those concepts—no matter what their phrasing is—mean the same thing.
The great thing about a formal ontology, in contrast to rigid taxonomies or classifications, is that it allows for indefinite expansion.
Given proper modeling, just about any kind of conceptual information, no matter the content, can find its place.
To disambiguate a concept's place in the ontology, often a context model is useful to improve the classification power.
The model typically applies rules to surrounding elements of the context to select the most valid classification.