komak konid ke bichare shodam

be man komak konid ke daram mioftam.
man in maghale ra az science direct mikham.
merc
http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6WM3-45P665F-8-1&_cdi=6923&_user=10&_orig=search&_coverDate=08%2F08%2F1993&_sk=998349997&view=c&wchp=dGLbVtz-zSkzS&md5=8a7e874b567e02a1aa2ea8186d843dc6&ie=/sdarticle.pdf

Journal Sound Vibration
Article in RAR +5% recover
http://rapidshare.com/files/114038492/j_sound_vibrat_.rar.html