Ubuntu Minolta Dimage Scan Dual III (AF-2840)
It is possible to run the official VueScan on Ubuntu with the following steps.
My system is (at time of writing) Ubuntu 18.04 LTS x64 Beta.
VueScan
Download VueScan from here, naturally selecting the latest Linux option.
In a terminal session 'cd' to the location of the download, most likely '~/Downloads':
tar zxvf downloadname.tgz
When I did this it created a subdirectory called 'VueScan'. Do a 'cd' to enter that location and type:
./vuescan
If it complains about missing libraries, move to the next section.
Libraries and Dependencies
The VueScan application may require some libraries in order to run. The Minolta site references Ubuntu 10.10, despite the latest release at time of writing being January 2018. The following will install the required libraries of x64 versions of Ubuntu:
sudo apt install libusb-0.1-4:i386 sudo apt install libgtk2.0-0:i386 sudo apt install libsm6:i386
The above could be run as one command line by concatenating the libraries, however, each gives you a better idea of the additional dependencies being installed alongside them.
Notes
The software is free-with-caveats; it superimposes many "Buy VueScan now!" across your scanned images.
Licensing is available here.