S . ▁Paris ▁paper ▁in ▁ 1 9 6 3 ▁and ▁a ▁SI AM ▁Control ▁J . ▁article ▁in ▁ 1 9 6 6 ). ▁He ▁invent ed ▁in ▁ 1 9 7 1 / 1 9 7 2 ▁ ▁the ▁so - called ▁swe eping ▁process , ▁which ▁is ▁a ▁specific ▁differential ▁inclusion ▁whose ▁right - hand ▁side ▁is ▁the ▁normal ▁cone ▁to ▁a ▁time ▁or ▁state - dependent ▁set ▁( that ▁may ▁be ▁convex ▁or ▁not ). ▁S we eping ▁processes ▁represent ▁a ▁nice ▁and ▁powerful ▁mathematical ▁framework ▁for ▁many ▁non - sm ooth ▁mechanical ▁systems , ▁including ▁L agr ang ian ▁systems , ▁with ▁applications ▁in ▁pl astic ity , ▁fluid ▁mechan ics , ▁elect rical ▁circ uits ▁with ▁non - sm ooth ▁components , ▁etc . ▁The ▁mathematical ▁literature ▁on ▁various ▁kinds ▁of ▁swe eping ▁processes ▁has ▁become ▁abund ant , ▁with ▁extensions ▁towards ▁non - con vex ▁sets ▁( es pecially ▁pro x - regular ▁sets ), ▁state - dependent ▁sets , ▁higher - order ▁processes ▁with ▁distribution al ▁solutions , ▁relationships ▁with ▁complement ar ity ▁dynam ical ▁systems , ▁etc . ▁ ▁After ▁ret iring ▁in ▁the ▁ 1 9 8 0 s , ▁he ▁started ▁an ▁inten se ▁research ▁activity ▁in ▁Gran ular ▁M atter , ▁and ▁contributed ▁to ▁sett le ▁the ▁so - called ▁More au - Jean ▁event - capt uring ▁( or ▁time - ste pping ) ▁numerical ▁scheme . ▁The ▁More au - Jean ▁scheme ▁may ▁be ▁seen ▁as ▁an ▁extension ▁of