The phrase "are introduced when a" is correct and usable in written English.
It can be used in contexts where you are explaining a process or a situation that occurs at a specific time or under certain conditions.
Example: "New policies are introduced when a significant change in the market occurs."
Alternatives: "are implemented when a" or "are established when a".
Some mild suspense is introduced when a character promises to talk about something at greater length, but a bit later.
Moreover, an improvement of the proposed method is introduced when a soft information on the decided bits is available.
But when coaching was introduced — when a colleague watched them try the new skills in their own classroom and provided suggestions — adoption rates passed ninety per cent.
But this can lead risk managers to ignore risks arising from market frictions, which can be introduced when a single institution accounts for a very large chunk of a market's transactions.
However, proteins containing more than three zinc-fingers do not bind as tightly as one might predict, and it appears that some type of strain is introduced when a six-finger protein is constructed with canonical linkers.
PVT stands for 'Product Validation Testing' and it's introduced when a device has reached its final build.
Hence, it is not accurate in the same study to compare ciphers implemented in different environment, and further inaccuracies can be introduced when a metric is estimated from other metrics.
In [4], an achievable rate region of primary versus secondary users' rates is introduced when a cognitive transmitter has full knowledge of the primary message in a two-transmitter two-receiver interference channel and the primary user cooperates with the secondary link through rate splitting introduced in [5].
We show the limited power of particular genetic loci to predict phenotypes or evolutionary response and the tremendous variance that is introduced when a genome is challenged by different environments.
Therefore, a pilot scheduling scheme based on user grouping according to different levels of pilot contamination is introduced when an extra set of orthogonal pilot sequences is available.
