is translated (fig) as to make demands on smb; (Beruf) to occupy smb. Re.: Collins German Dictionary, ISBN 0-00-470406-1 I hope it might help a little.
Good luck, Rebecca Holmes-Löffler!

as it is logistics, could be?

I think something like "collection" or "receipt" would actually work here, especially for your second example, which you could probably translate as "in-trays" (trays designed to collect or receive things are basically in-trays).

I also think "collection of loose packages" would be fine for the third example.

The first example is a little more problematic, as it doesn't seem entirely logical to collect or receive things with a scanner. Unless perhaps the scanner is collecting data, in which case maybe you could simply say "scanning", period!

I don't know how much assistance this has been, but I hope I've helped you a little bit on the road to figuring out what "vereinnahmen" is doing in your text.

There are actually three different words here (although two have the same meaning); the first, "Vereinnahme", I think is "recording" as one would, with a scanner; the second, Vereinnahmung, looks like "records" (i.e. hard copies which have been made), and the third, "Vereinnahmen" is either "vereinnahmen" used as a noun, or (more likely, I think) the plural form of (1).
HTH, and good luck, Rebecca.

I would call it

processing by handheld scanner
trays for processing
processing of individual parcels

perhaps. A scanner acquires data, for example

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Note added at 2003-05-20 14:59:14 (GMT)
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or, perhaps incorporation

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Note added at 2003-05-23 05:22:56 (GMT) Post-grading
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by the software, I should have said, in the last note.
Vereinnahmen seems a more involved than merely registering, logging, and the like.