The phrase "at certain length" is not correct in standard written English.
You might be trying to convey a meaning related to a specific duration or extent, but the phrase is awkward and unclear.
Example: "The project will be discussed at certain length during the meeting."
Alternatives: "in some detail" or "to a certain extent."
The CFS is curved by using the method of cut-curving in which the CFS section is cut at a certain length and then curved into desired profile.
At a certain length scale of observation, these materials appear in the form of a random network of cross-linked (connected) filaments.
At a certain length the dominant wavelength of the sinusoidal disturbances is larger than the length between two cross-over points and the disturbances will not grow further.
The idea of this approach is to use different levels of modeling, each developed to study phenomena at a certain length scale.
Mayakovsky was an enormously persistent and demanding (and jealous) lover … Lili was happy to sleep with Mayakovsky, but held him at a certain length for nearly three years before suggesting he move in with herself and Osip, an arrangement that lasted on and off for the rest of his life.
I discuss then locally symmetric varieties, and at a certain length the quotients of Abelian varieties by a cyclic group acting freely, which are here called Bagnera De Franchis varieties.
Using a classic eyeblink experiment, they trained animals to blink at a certain length of time after they heard a specific tone in order to avoid a puff of air directed at their eyes.
At a certain length, the telomeres signal the cell to stop dividing, since too short telomeres may cause genomic instability that accelerates the accumulation of genetic changes responsible for tumorigenesis.
For example if you like short skirts but only at a certain length wear that length and if you like long skirts do the same.
