'has been specializing' is correct and usable in written English.
You can use it to refer to a continuing or repeated action. For example: "John has been specializing in ecological research for the past 5 years."
The nursery, which has been specializing in herbs for 27 years, grows about 25 rosemaries and 40 different lavenders, as well as many other herbs and specialty vegetables.
The bridegroom, 37, is a partner in the Advanced Pain Center in Alhambra, Calif., where he has been specializing in pain management and rehabilitation for the elderly.
In recent years the band has been specializing in the music of John Coltrane; his work may well be played this weekend.
Still, when it comes to flashy portraits of demented, child-destroying moms and dads (especially moms), you can't beat the theater, which has been specializing in cruel and unusual parents since the bloody old days of Medea and Clytemnestra.
This is another of the iron-buttercup roles in which Miss Hawn has been specializing since "Private Benjamin," films in which her inspired dizziness masks an unexpectedly strong will.
Mr. Shenkman has been specializing in math-related stories lately -- he was featured in the movie "Pi" -- and the subject seems to be handy for him in making acting analogies.
While it is possible to re-train scientists to use emerging high-performance computing (HPC) models, it is much more effective to provide them with a higher-level programming environment that has been specialized to their particular domain.
This study introduces the reader to a "people centered" and multidimensional definition of the "smartness" of an ecosystem and to its bottom-up detection, that here has been specialized to the case of a learning ecosystem: a university campus.
The proposed approach has been specialized and tested in three variants, each aimed at detecting one of the three categories of mandatory, prohibitory and danger traffic signs, according to the experimental setup of the recent German Traffic Sign Detection Benchmark competition.
First, we describe a generic framework, EDS, which has been specialized for the generation of audio features and is used for supervised classification and regression problems.
