S20  Vibroacústica    Titulo: ACTIVE NOISE CONTROL IN DUCTS USING ADAPTIVE ALGORITHM   Resumo : ACTIVE NOISE CONTROL IN CLOSED CAVITIES IS A CLASSICAL ENGINEERING PROBLEM. THE NOISE CONTROL CAN PRODUCE QUITE ENVIRONMENTS WHICH ARE MORE SAFE, PRODUCTIVE, AND COMFORTABLE. AN EXPRESSIVE NUMBER OF LOW FREQUENCY NOISE PROBLEMS HAVE BEEN SOLVED WITH THE ACTIVE NOISE CONTROL TECHNIQUE. THIS PAPER PRESENTS SIMULATED AND EXPERIMENTAL RESULTS OF FEEDFORWARD CONTROL IN DUCTS USING ADAPTIVE LEAST MEAN SQUARE (LMS) ALGORITHM IN ITS VERSION CALLED FILTERED-X LMS (FXLMS). A FLEXIBLE TEST RIG IS PRESENTED, WHICH IS EASY TO ASSEMBLE IN DIFFERENT CONFIGURATIONS IN ORDER TO ANALYZE ACTIVE NOISE CONTROL PROBLEMS IN DUCTS. PROBLEMS WITH SINGLE SOURCES AND MULTIPLE ERROR SENSORS ARE INVESTIGATED. KEYWORDS: ACTIVE NOISE CONTROL IN DUCTS, ACTIVE CONTROL, ADAPTIVE ALGORITHM, FILTERED-X LMS CONTROLLER.     Autores : Arruda, José Roberto França Danadon, Lázaro Valentin Nunes, Ronaldo Fernandes Santos, José Maria Campos dos     Trabalho Completo :   COBEM99 | Comissão  Organizadora | Palestras | Sessões Técnicas | Autor | Simpósios e Sessões Especiais | Revisores |  Título  dos  Trabalhos | Local