Aperture has a "Merge" mode when reimporting an Aperture library, that has been edited, back to the library it has been copied from.
- Connect your travel mac to your iMac in target disk mode (OS X Lion: Transfer files between two computers using target disk mode) so that your iMac sees the notebook as a disk (requires Firewire), or copy your Aperture library from the notebook to an external disk.
- Then launch Aperture on the iMac and use "File > Import > Library".
When prompted opt for "Merge" not "Add" and select to keep the versions from the Notebook.
See the manual: Working with Library Files, To merge the modified library from the second computer into the library of the first computer
As a precaution I'd repair both the libraries before merging: