automation automatisation businessrelocation collectivebargaining constructionindustry constructionworkers electronicmonitoringintheworkplace employeerights entrepôts laborcosts laborunions managementrights openandclosedshop plantshutdowns pratiquesrestrictivesenrelationsindustrielles restrictivepracticesinlaborrelations subcontracting surveillanceélectroniqueenmilieudetravail technologicalunemployment unitedstates wages warehouses